Note: Descriptions are shown in the official language in which they were submitted.
217e77
1
VARIABLE-(nJHEEL-GAUGE BOGIE FOR ROLLING STOCK
BACKGROUND OF THE INVENTION
Field of the Invention
The present invention relates to a variable-wheel-gauge
bogie for rolling stock and a wheel gauge changing track
arrangement and, more particularly, to a variable-wheel-
gauge bogie capable of automatically adjusting its wheel
gauge to a rail gauge of a track, and the wheel gauge
1.0 changing track arrangement for changing the wheel gauge of
the variable-wheel-gauge bogie.
Description of the Prior Art
There have been proposed various variable-wheel-gauge
bogies for rolling stock intended for use on a track of a
standard rail gauge of 1435 mm, such as tracks for the
Shinkansen line, and on a track of a narrow rail gauge of
1067 mm, such as a track for the old line, and various
wheel gauge changing track arrangements.
A wheel gauge changing technique disclosed in, for
example, JP-A No. 5-39036 employs a car lifting device,
such as a pneumatic cylinder actuator, mounted on a
railroad car and changes the wheel gauge of a bogie
supporting the railroad car by lifting up the railroad car
by the car lifting device and shifting the wheels by
actuators after stopping the railroad car.
In a variable-wheel-gauge bogie disclosed in JP-A No.
6-40335, a tubular sliding shaft is mounted on an axle
restrained from rotation, wheels are supported on bearings
on a tubular sliding shaft and a stator of a drive motor
is fixedly coupled with the tubular sliding shaft, and the
sliding shaft is moved axially to move both the wheels and
the drive motor for wheel gauge changing. Journal boxes,
the axle and the sliding shaft are provided with through
holes for receiving power-driven positioning-and-locking
pins. The wheels are positioned and locked in place in a
desired wheel gauge by fitting the positioning-and-locking
21'i 8 I'~ 7
pins in the corresponding through holes of the journal
boxes, the axle and the sliding shaft, respectively, to
unite the journal boxes, the axle and the sliding shaft
fixedly. Since locked in place, the wheels are unable to
move transversely so that a fixed wheel gauge is maintained
while the variable wheel gate bogie is traveling.
In a variable-wheel-gauge bogie for rolling stock,
disclosed in JP-A No. 5-246329, journal boxes supporting
the axles of independent wheels are supported on a wheel
frame by a parallel linkage. A car support base is
installed along a gauge changing section of a track. When
a railroad car supported on the variable-wheel-gauge bogie
enters the gauge changing section at a low traveling speed,
the weight of the railroad car is born by the car support
1~ base to relieve the wheels of the weight of the railroad
car, so that the links of the parallel linkage supporting
the unloaded wheels are able to move freely and the wheel
gauge can be adjusted to a rail gauge. The wheels are
fixed in place by fitting pins in holes formed at the
opposite ends of the parallel linkage.
Reference is made in "Rapid Trains and Sleeping Cars
in Europe", Sharyou Gijutsu, No. l63, Nippon Tetsudo
Sharyo Kogyo-kai FDN to a Talgo automatic wheel gauge
changing system for railroad cars of the French National
Railways and the Spanish National Railways that travel on
both standard tracks of the standard gauge of 1435 mm and
broad tracks of the broad gauge of 1668 mm. The railroad
car of the Talgo automatic wheel gauge changing system is
not equipped with any driving mechanism for locomotion,
and employs independent wheels that are not connected by
a signal axle or the like and move transversely together
with their axles for changing the wheel gauge. When the
railroad car passes a gauge changing section, the weight
of the railroad car is born by additional load bearing
3~ rails laid along the rails of the gauge changing section
to relieve the wheels of the weight of the railroad car,
so that the wheels are able to move freely transversely
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for automatic wheel gauge changing while the railroad car
is traveling.
The wheel gauge changing systems disclosed in JP-A
Nos. 5-39036 and 6-40335, however, need to lift up a11 the
railroad cars of a train simultaneously for wheel gauge
changing operation by the car lifting devices while the
railroad cars are stopped. Therefore the wheel gauge
chang-ing operation takes much time and, when the train
consists of a large number of railroad cars, many car
lifting devices or a very long car support structure is
necessary.
In a wheel positioning-and-locking mechanism using the
positioning-and-locking pins, the diameter of the through
holes must be slightly larger than that of the correspond-
ing positioning-and-locking pins to enable the position-
ing-and-locking pins to be smoothly fitted in the through
holes when positioning and locking the wheels in place.
Therefore, the wheel positioning-and-locking mechanism for
locking the wheel in place unavoidably permits play and,
consequently, each pair of wheels on an axle move individu-
ally transversely and the wheel gauge varies minutely and
continually. Such a minute variation of the wheel gauge
enhances the meandering motion of the railroad car during
high-speed traveling, causing problems including spoiling
riding comfort in the traveling performance of the railroad
car.
A very high impulsive transverse force acts on the
bogie when the bogie travels along a curve or passes a
railroad switch. Therefore, the play between the compo-
nents of the wheel positioning-and-locking mechanism cause
problems including distortion, breakage and abrasion of the
structural components of the bogie that shortens the life
of the bogie.
Since the journal box is not fixed and is elastically
suspended from the frame of the bogie by an axle spring,
a special means is necessary for aligning the through hole
of the journal box with those of the axle and the sliding
'- 4
shaft.
Since the wheel gauge changing system disclosed in
JP-A No. 5-246329 shifts the wheels by the turning motion of
the links of the parallel linkage when changing the wheel
gauge of the railroad car, the force generated by the
weights of the wheels, the axle and the journal boxes and
acting on an elongate axle guide member increases as the
parallel links approach a horizontal position.
Consequently, the elongate axle guide member is liable to be
distorted or broken and hence the wheel gauge changing
system is unsatisfactory in reliability.
Although the Talgo automatic wheel gauge changing
system that shifts each pair of independent wheels
transversely together with the journal boxes is suitable for
application to a single axle bogie, the Talgo automatic
wheel gate changing system has structural difficulties in
applying the same to a two-axle bogie. It is very difficult
to apply the Talgo automatic wheel gauge changing system to
a bogie for narrow rail gauge because of dimensional
restrictions thereon.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present
invention to provide a variable-wheel-gauge bogie for
rolling stock, capable of changing its wheel gauge while
travelling and of functioning with high safety and
reliability, and applicable to railroad cars for narrow
gauges and those equipped with drive motors, and to provide
a wheel gauge changing track arrangement for use in
combination with the variable-wheel-gauge bogie.
Another object of the present invention is to
provide a variable-wheel-gauge bogie for rolling stock,
having a wheel positioning-and-locking mechanism capable of
locking wheels in place without permitting any play with
high safety and reliability.
...
According to a first aspect of the present
invention; there is provided a system for changing the gauge
of a rolling stock bogie having, a pair of side beams (1)
for supporting a wheel axle (4) on a rail road via wheel
(9), a journal box (3) provided under each of said side
beams (1) to receive an end of said wheel axle (4),and an
axle sleeve (7) rotatably supporting said wheel (9) thereon
and fitted on said wheel axle (4) slidably along the wheel
axle, comprising: first engagement means (15A, 15B) formed
on an outer peripheral surface of said axle sleeve (7):
second engagement means (16, 17) formed on an inside surface
of said journal box (3) and provided to selectively engage
said first engagement means (15A, 15B) when said wheel (9)
is positioned to match one of different gauges; a wheel
gauge changing rail (23) laid between two rails (21,22) of
different gauges and provided to allow said rolling stock
bogie to roll thereon; a car support rail (26, 27) provided
in parallel with said wheel gauge changing rail (23) to
separate the rolling stock bogie from said sleeve (7) and
said wheel (9) in a vertical direction to disengage said
second engagement means (16, 17) from said first engagement
means (15A, 15B) while said rolling stock bogie rolls on
said wheel gauge changing rail (23) so as to precisely
change said gauge without stopping the rolling stock bogie;
and a fastening device (18) for fastening together said
journal box (3) and said wheel axle (4) to restrain the
journal box from vertical movement relative to the wheel
axle and to release the journal box from the wheel axle
before the rolling stock bogie starts travelling on the
wheel gauge changing rail (23).
Preferably, each axle is provided with circular
grooves in its end portions, respectively, each journal box
has an extension fitted in the circular groove of the axle,
the fastening device has a wedge member held adjacent to the
extension so as to be forced into the circular groove of the
axle, and wedge biasing members for biasing the wedge member
toward the circular groove, the wedge member presses the
extension against the side surface of the annular groove by
6
its wedging action when forced into the circular groove of
the axle to fasten together the journal box and the axle.
Desirably, each car support rail has a wedge guide
rail transversely projecting therefrom and capable of
S retracting the wedging member from the circular groove of
the axle against the biasing force of the wedge biasing
members to disengage the journal box from the axle.
Preferably, the wheel gauge changing track
arrangement further comprises guide rails laid so as to
extend on both sides of and along the wheel gauge changing
rails and to come into contact with the side surfaces of the
wheels, and biasing members for biasing the guide rails to
bring the guide rails into contact with the side surfaces of
the wheels.
Desirably, each journal box is provided with shims
for thickness adjustment on its lower surface that comes
into contact with the car support rail.
According to a second aspect of the present
invention, a variable-wheel-gauge bogie for rolling stock,
capable of automatically changing its wheel gauge while
travelling on wheel gauge changing rails interconnecting
rails of a broad-gauge track of a broad rail gauge and rails
of a narrow-gauge track of a narrow rail gauge comprises:
journal boxes suspended from side beams of a truck frame by
elastic members, axles vertically movably supported on the
journal boxes, axle sleeves axially slidably put on the
axles for movement between a position for the broad rail
gauge and a position for the narrow rail gauge, wheels
supported for rotation on bearings on the axle sleeves,
respectively, drive motors for driving the wheels for
rotation, supported
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on the axle sleeves, respectively, on-sleeve locking
members formed on the outer circumferences of the axle
sleeves, respectively, and on-box locking members formed
on the journal boxes, capable of engaging with the
on-sleeve locking members, respectively, to restrain the
axle sleeves from axial movement when each of the axle
sleeves is at a position for the broad rail gauge or at
a position for the narrow rail gauge, and when the weight
of the truck frame acts thereon through the journal boxes,
and fastening devices each for fastening together the
journal box and the corresponding axle to restrain the
journal box from vertical movement relative to the axle
sleeve, and for disengaging the journal boxes from the
axles immediately before the variable-wheel-gauge bogie
starts traveling on the wheel gauge changing rails.
According to a third aspect of the present invention,
a variable-wheel-gauge bogie for rolling stock, capable
of automatically changing wheel gauge while a railroad car
is traveling on wheel gauge changing rails interconnecting
rails of a broad-gage track of a broad rail gage and rails
of a narrow-gauge track of a narrow rail gauge comprises:
pairs of j ournal boxes suspended from side beams of a truck
frame by elastic members, and provided with locking holes
in their upper walls, respectively, car support units each
formed on the lower surface of each journal box to support
the body of the railroad car when changing wheel gauge,
axles vertically movably supported on the journal boxes
with the opposite ends thereof contained in the journal
boxes, respectively, pairs of axle sleeves axially
slidably put on the axles, respectively, for movement
between a position for the broad rail gauge and a position
for the narrow rail gauge, pairs of wheels supported for
rotation on bearings on the pairs of axle sleeves,
respectively, pairs of locking blocks attached to the
outer circumferences of the pairs of axle sleeves,
respectively, and each having an upper load bearing
surface for bearing the weight of the railroad car through
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the journal box, and sliding side walls that slide along
inner side guide surfaces of the j ournal box when the axle
moves relative to the journal box, two conical locking
projections pro-jecting from the upper load bearing surface
of each locking block so as to be fitted in the locking
hole of the journal box when the axle sleeve is at a
position for the broad rail gauge or the narrow rail
gauge, vibration isolating units each disposed so as to
surround the locking hole and to be in elastic contact
with the conical locking projection as fitted in the
locking hole.
Desirably, the variable-wheel-gauge bogie is provided
with central stoppers each projecting from the middle
portion of each axle to restrain the axle sleeve from
moving beyond the position for the narrow rail gauge
toward the middle of the axle, end stoppers projecting
from the oppo- site end portions of each axle to restrain
the axle sleeves from moving beyond the positions for the
broad rail gauge toward the ends of the axle, sliding
members projecting from both sides of each end stopper and
each having a taper upper end, guide cavities formed in
each journal boxes to guide the sliding members for
vertical movement, respectively, and vibration isolating
units each disposed in an upper portion of each guide
cavity so as to be in elastic contact with the surface of
the taper upper end of the sliding member.
Preferably, the conical locking projection consists
of a cylindrical portion of a substantially fixed diameter
and a predetermined height, and a tapered conical portion,
the locking hole has a lower section of a diameter
substantially equal to that of the cylindrical portion of
the conical locking projection, and an upper section of
a diameter far greater than that of the lower section, the
vibration isolating unit for locking projection is disposed
so as to surround the upper section of the locking hole
and to be in elastic contact with the conical portion of
the conical locking projection.
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Desirably, the vibration isolating unit for locking
pro-jection comprises an outer ring fixedly fitted in the
upper section of the locking hole, a rubber vibration
isolator fixed to the inside surface of the outer ring, and
an inner ring fixed to the inside surface of the rubber
vibration isolator, and the inner ring is moved by the
conical portion of the conical locking projection to deform
the rubber vibration isolator when the conical locking
projection is fitted in the locking hole.
Preferably, the vibration isolating unit for locking
projection has a annular plate spring having a V-shaped
section.
Desirably, the vibration isolating unit for locking
projection comprises a wedge ring fitted in the upper
section of the locking hole, a cover covering the upper
open end of the upper section of the locking hole, and an
elastic member disposed between the upper surface of the
wedge ring and the cover to bias the wedge ring downward,
the conical portion of the conical locking projection
comes into engagement with the inner circumference of the
wedge ring when the conical locking projection is fitted
in the locking hole.
Preferably, the sliding members are outward extensions
of the opposite side surfaces of the end stopper, and the
guide cavities are sliding grooves formed in the opposite
side walls of the journal box.
Desirably, the vibration isolating unit for sliding
member comprises a box fitted in an opening formed in each
side wall of the journal box, detachably attached to the
sides wall and having a recess opening into the interior
of the journal box, a rubber vibration isolator attached
to the surface of the recess of the box, and a liner fixed
to the rubber vibration isolator so as to be in contact
with the taper upper end of the sliding member.
Preferably, the vibration isolating unit for sliding
member has a plate spring having a V-shaped cross section
and in elastic contact with the end surface of the taper
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upper end portion and the opposite side surfaces of the
sliding member.
Desirably, the sliding members are pins projecting
upward from brackets projecting from the opposite side
surfaces of the end stopper, and the guide cavities are
vertical through holes formed in the journal box.
Preferably, the vibration isolating unit for sliding
member comprises an outer ring fixedly disposed in the
upper portion of the guide cavity, a rubber vibration
isolator fixed to the inside surface of the outer ring,
and an inner ring fixed to the inside surface of the
rubber vibration isolator, and the inner ring is moved by
the taper upper end of the sliding member so as to deform
the rubber vibration isolator when the sliding member is
inserted in the guide cavity.
According to the present invention, the wheel gauge
can be changed without stopping the railroad car while the
railroad car is traveling, and the present invention is
applicable to railroad cars for narrow gauges and railroad
cars mounted with drive motors. Since the locking members
on the journal boxes, for restraining the axle sleeves from
axial movement engage with the locking members on the axle
sleeves, respectively, when the weight of the railroad car
acts thereon, the locking members are engaged securely so
that the variable-wheel-gauge bogie for rolling stock func-
tions with high safety and high reliability.
Since the conical locking projections are surely
fitted in the locking holes and the vibration isolating
units come into elastic contact with the circumferences
of the conical locking projections, respectively, dynamic
shocks attributable to the play of the conical locking
projections in the corresponding locking holes is ab-
sorbed, which prevents the abrasion of parts and ensures
highly stabilized traveling performance.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. lA is a schematic plan view of a variable-wheel--
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m
gauge bogie in a first embodiment according to the present
invention;
Fig. 1B is a side view of the variable-wheel-gauge
bogie of Fig. lA;
Fig. 2 is a fragmentary longitudinal sectional view
of a variable-wheel-gauge bogie in the first embodiment
as set in a geometry for a narrow rail gauge;
Fig. 3 is a fragmentary longitudinal sectional view
of the variable-wheel-gauge bogie in the first embodiment
lU as set in a geometry for a standard rail gauge;
Fig. 4 is a cross-sectional view taken along the line
IV-IV in Fig. 3;
Fig. 5 is a longitudinal sectional view taken along
the line V-V in Fig. 4;
Fig. 6 is a side view showing the relation between an
axle, a journal box and a locking member included in the
variable-wheel-gauge bogie of Fig. 2;
Fig. 7A is a plan view of a wheel gauge changing track
arrangement in the first embodiment;
Fig. 7B is a side view of the wheel gauge changing
track arrangement of Fig. 7A;
Fig. 8 is an enlarged longitudinal sectional view of
an axle and the associated components included in a
variable-wheel-gauge bogie in a second embodiment according
to the present invention;
Fig. 9 is an enlarged side view of a journal box and
the associated components included in the variable-wheel-
gauge bogie in the second embodiment;
Fig. 10 is a plan view showing the relation between
a journal box and a locking block included in the
variable-wheel-gauge bogie in the second embodiment;
Fig. 11 is a cross-sectional view taken along the line
XI-XI in Fig. 8;
Fig. 12 is a longitudinal sectional view showing the ,
relation between a locking hole and a conical locking
projection included in a variable-wheel-gauge bogie in the
second embodiment;
217g17
Fig. 13 is a half-sectional view corresponding to Fig.
12;
Fig. 14 is a sectional view showing the relation
between a sliding member and a vibration isolating unit
included in a variable-wheel-gauge bogie in the second
embodiment;
Fig. 15 is a sectional view taken along the line XV-XV
in Fig. 14;
Fig. 16 is a sectional view taken along the line
XVI-XVI in Fig. 15;
Fig. 17 is a fragmentary cross-sectional view of
a
wheel gauge changing
track arrangement;
Fig. 18 is a half-sectional
view of a modification
of
the vibration olating unit;
is
Fig. 19 is a longitudinal sectional view of a
vibra-
tion isolating unit in another modification;
Fig. 20 is a plan view of a wedging ring;
Fig. 21 is a sectional plan view of a vibration iso-
lating unit for a sliding member;
Fig. 22 is a sectional side view of a vibration iso-
lating unit for a sliding member;
Fig. 23 is a side view of a vibration isolating unit
for a sliding
member; and
Fig. 24 is a plan view of a vibration isolating unit
for a sliding
member.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A first embodiment of the present invention will be
described hereinafter with reference to Figs. 1 to 7.
First the construction of a variable-wheel-gauge bogie for
rolling stock will be described. Referring to Fig. lA,
journal boxes 4 are suspended from the side beams 1 of a
truck frame by axle springs 2, i.e., elastic members. The
axle springs 2 may be coil springs, pneumatic springs or
rubber springs. The flat lower surfaces of the journal
boxes 3 serving as sliding surfaces 3a are at the same
level. Fixed axles 4 are supported on the journal boxes
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3.
Referring to Figs. 1B, 2 and 3, a positioning projec-
tion 5 is formed on each axle 4 at the middle of the axle
4, and positioning circular grooves 6 are formed in each
axle 4 at some distance from its opposite ends. Two axle
sleeves 7 are put on each axle 4 so as to be axially
movable on the axle 4. Each axle sleeve 7 is supported
on the journal box 3 and restrained from rotation by a
locking block 13. The axle 4 and the axle sleeve 7 are
not restrained from rotation relative to each other. A
wheel 9 is supported for rotation on a taper roller
bearing 8 at a substantially middle portion of the axle
sleeve 7. Preferably, the wheel 9 is an elastic wheel
formed of a composite material that will reduce the
1~ unsprung weight of the bogie and vibrational acceleration.
A stator 10a included in a drive motor 10 is fixedly
mounted on the axle sleeve 7 at a position on one side of
the wheel 9 nearer to the middle of the axle 4. A rotor
lOb included in the drive motor 10 has one end supported
on a bearing 11 on the axle shaft 7 and the other end
fixed to a side surface of the wheel 9. A brake disk 12
is formed on the outer circumference of the rotor lOb.
The tubular locking block 13 is mounted on a portion
of the axle sleeve 7 near the end of the axle 4 and
2~ fixedly joined to the axle sleeve 7 by splines 14. The
locking block 13 extends into the journal box 3, has
sliding side walls 13a as shown in Fig. 4 and is able to
move vertically relative to the journal box 3.
As shown in Fig. 4, the locking block 13 has a pair
of upper inclined surfaces 13b, and two axially elongate
locking projections 15A and 15B of the same shape are
formed on each upper inclined surface 13b as shown in Fig.
5. The locking projections 15A and 15B has a trapezoidal
longitudinal section. The center distance between the
locking projections 15A and 15B is equal to half the
difference between a broad rail gauge and a narrow rail
gauge. More concretely, the broad rail gauge is the
21 '~ ~ 17 '~
standard rail gauge of 1435 mm and the narrow rail gauge
is 1067 mm in this embodiment, and hence the center
distance between the locking projections 15A and 15B is
(1435 - 1067)/2 - 184 mm. Locking groove 16 having a
S shape complementary to that of the locking projections 15A
and 15B are formed in the inside surface of the journal
box 3 facing the upper inclined surfaces 13b of the locking
block 13. When the locking projection 15A or 15B is
fitted in the corresponding locking recess 16 as shown in
Fig. 5, the axle sleeve 7 is unable to move axially.
The positional relation between the locking projec-
tions 15A and 15b and the corresponding locking recess 16
is determined so as to meet the following conditions. The
distance between the pair of wheels 9 on each axle 4 corre-
sponds to the narrow rail gauge as shown in Fig. 2 when the
locking projection 15A is fitted in the locking recess 16,
and the distance between the pair of wheels 9 corresponds
to the broad rail gauge as shown in Fig. 3 when the
locking projection 15B is fitted in the locking recess 16
as shown in Fig. 5. The locking projections 15 and the
locking recess 16 are locking part of the axle sleeve 7 and
that of the journal box 3, respectively, may be formed in
any suitable shape other than the trapezoidal shape,
provided that the locking projections 15 and the locking
recess 16 are able to restrain the axle sleeve 7 from
axial movement when engaged.
Although this embodiment is provided with the two
locking projections 15 and the one locking recess 16, the
locking block may be provided with one locking projection
15 and the j ournal box 3 may be provided with two locking
recesses 16. The journal box 3 may be provided with a
locking projection or two locking projections and the
locking block 13 may be provided with two locking recesses
or one locking recess.
As shown in Figs . 2 and 3 , the j ournal box 3 has a
sliding guide extension 17 having vertical guide legs . The
guide legs extend vertically on the opposite sides of a
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reduced part of the axle 4 defined by the circular groove
6 formed in the end portion of the axle 4. The guide legs
of the guide extension 17 receiving the reduced portion
of the axle 4 therebetween guides the journal box 3 when
the journal box 3 move vertically relative to the axle 4
and the axle sleeve 7. The guide extension 17 serves also
as a stopper for limiting the outward axial movement of
the axle sleeve 7.
Referring to Figs. 2, 3 and 6, a bifurcate fastening
member 18 is inserted in the circular groove 6 of the axle
4. The fastening member 18 has two wedging legs 18a and
18b. A pair of rods 19 are joined to the fastening member
18, and coil springs 20 are extended between the lower ends
of the rods 19 and the j ournal box 3 , respectively, to bias
the rods 19 downward. Thus, the fastening member 18 is
biased downward through the rods 19 by the coil springs 20
so that the wedging legs 18a are inserted in the circular
groove 6. The working surfaces of the guide extension 17
or the fastening member 18 are longitudinally tapered.
When the wedging legs 18a are forced into the circular
groove 6 by the resilience of the coil springs 20, the
guide exten- sion 17 is pressed firmly against the side
surface of the circular groove 6 of the axle 4 by a
wedging action. Consequently, the journal box 3 and the
axle 4 are firmly united together to prevent perfectly the
vertical movement of the journal box and the axle 4
relative to each other. A wheel gauge changing track
arrangement will be described hereinafter.
Referring to Figs. 7A and 7B showing part of a narrow
track of a narrow gauge having narrow-track rails 21, part
of a standard track of the standard rail gauge having
standard-track rails 22, the narrow-track rails 21 and the
standard-track rails 22 are interconnected by a wheel gauge
changing track having wheel gauge changing rails 23. The
rail gauge of the wheel gauge changing track having the
wheel gauge changing rails 23 increases gradually from one
end thereof joined to the narrow track having the narrow--
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m
track rails 21 toward the other end thereof joined to the
standard track having the standard-track rails 22.
Portions of the narrow-track rails 21 and the
standard-track rails 22 in sloping sections L of a
predetermined length continuous with the wheel gauge
changing track are declined toward the joints of the
narrow-track rails 21 and the wheel gauge changing rails
23, and those of the standard-track rails 22 and the wheel
gauge changing rails 23, respectively, so that the joints
are sunk by a predetermined height H from the level of the
narrow track and the standard track.
Guide rails 24 are laid on both sides of each wheel
gauge changing rails 23 along the entire length of the
wheel gauge changing rails 23 and portions of the
narrow-track rails 21 and the standard-track rails 22
continuous with the wheel gauge changing rails 23. The
opposite guide rails 24 are biased toward each other by
springs 25 so that the guide rails 24 are pressed against
the side surfaces of the wheels 4, respectively.
A pair of car support rails 26 are laid on the outer
side of two sets each of the rails 21, 22 and 23, respec-
tively, so as to extend in a substantially horizontal plane
at a predetermined height from the ground. The car support
rails 26 are laid so as to extend right under the sliding
surfaces 3a of the journal boxes 3 so that the sliding
surfaces 3a of the journal boxes 3 come into sliding
contact with the car support rails 26. As shown in Figs.
2 and 3, fastening member raising rails 27 are supported
on the car support rails 26 so as to extend on the outer
side of the car support rails 26 and right under the rods
19 joined to the fastening members 18. Each fastening
member raising rail 27 has a sloping section 1 correspond-
ing to a section of the narrow-track rail 21 continuous
with the sloping section L, and sloping up toward a
horizontal section corresponding to the the sloping section
L continuous with the narrow-track rail 21, the horizontal
section of the wheel gauge changing rail 23 and the
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m
sloping section L continuous with the standard-track rail
22, and a sloping section 1 corresponding to a section of
the standard-track rail 22 continuous with the other
sloping section L, and sloping down from the horizontal
section.
The operation of the first embodiment will be de-
scribed hereinafter on an assumption that the railroad car
travels from the narrow-track rails 21 of the narrow track
to the standard-track rails 22 of the standard track.
Referring to Figs. 7A and 7B, the variable-wheel-gauge
bogie is in the geometry shown in Fig. 2 while the railroad
car is traveling on the narrow-track rails 21 and the
locking projections 15A are fitted in the locking recesses
16, respectively. The rotors 10b of the drive motors 10
rotate together with the wheels 9, respectively. Reactive
torques corresponding to the driving torques of the wheels
9 are transmitted through the axle sleeves 7, the sliding
side walls 13a of the locking blocks 13, the journal boxes
3 and the axle springs 2 to the side beams 1 of the truck
frame to drive the railroad car for traveling.
When the variable-wheel-gauge bogie enters a section
of the narrow-track rails 21 corresponding to the up
sloping section Z of the raising rails 27, the raising
rails 27 raises the rods 19 against the force of the
springs 20 to raise the fastening members 1$ by a prede-
termined distance. Consequently, the wedging effects of
the fastening members 18 are removed, whereby the journal
boxes 3 are able to move vertically relative to the axles
4. Subsequently, the variable-wheel-gauge bogie enters the
down sloping section L of the narrow-track rails 21 and
starts traveling downward. Immediately after the
variable-wheel-gauge bogie has started traveling downward,
the sliding surfaces 3a of the journal boxes 3 come into
contact with the car support rails 26, and then the
journal boxes 3 are kept in a substantially horizontal
plane while the axles 4 and the axle sleeves 7 move
downward relative to the journal boxes 3 according to the
217817'i
m
inclination of the down sloping section L. Consequently,
the locking projections 15A come off the corre-sponding
locking recesses 16 to allow the axle sleeves 7 to move
axially. The axle sleeves 7 are allowed to move axially
before the variable-wheel-gauge bogie reaches the terminal
end of the down sloping section L at the latest.
Then, the variable-wheel-gauge bogie starts traveling
on the wheel gauge changing rails 23 of the wheel gauge
changing track gradually widening toward the standard
track. Then, the wheels 9 are guided by the guide rails
24 biased toward the wheels 9 by the springs 25 as the
wheels roll on the wheel gauge changing rails 23, so that
the wheels 9 are shifted gradually outward together with
the associated axle sleeves 7 on the axles 4. When the
1~ variable-wheel-gauge bogie arrives at the terminal end of
the wheel gauge changing rails 23, the outer ends of the
sleeves 7 come into contact with the extensions 17 of the
corresponding journal boxes 3 as shown in Fig. 3, and the
axle sleeves 7 are stopped. In this state, the distance
between the pair of wheels 9 on each axle 4 is equal to
the standard rail gauge, and the locking projections 15B
are located opposite to the locking recesses 16, respec-
tively. Since the truck frame of the variable-wheel-gauge
bogie is supported through the journal boxes 3 on the car
2~ support rails 26 while the variable-wheel-gauge bogie is
traveling on the wheel gauge changing rails 23 or on
sections of the narrow-track rails 21 or the
standard-track rails 22 near the ends of the wheel gauge
changing rails 23, the wheels 9 and the axle sleeves 7 are
lightly loaded, and hence the axle sleeves 7 are able to
slide lightly according to the variation of the rail gauge
of the wheel gauge changing track.
Then, the variable-wheel-gauge bogie moves from the
wheel gauge changing rails 23 to the standard-track rails
3~ 22. While the variable-wheel-gauge bogie is traveling in
the up sloping section L of the standard-track rails 22,
the axles 4 and the axle sleeves 7 move upward relative
2178177
m
to the journal boxes 3, the locking projections 15B
approach the corre-sponding locking recesses 16 of the
journal boxes and, finally, the locking projections 15B
are fitted in the corresponding locking recesses 16.
Consequently, the axle sleeves 7 is locked in place and
the wheels 9 are fixed at positions for the standard rail
gauge.
Then, as the variable-wheel-gauge bogie travels in a
section of the standard track corresponding to the down
sloping section 1 of the guide rails 27, the fastening
members 18 are lowered through the rods 19 by the springs
20, and press the guide extensions 17 against the axles 4
by their wedging effect to fasten the axle sleeves 7
firmly to the axles 4.
1> The variable-wheel-gauge bogie is provided with the
fastening members 18 for the following purposes. The
locking projection 15B of each axle sleeve 7 is fitted in
the locking recess 16 of the journal box 3 as the journal
box 3 is lowered by the weight of the truck frame when the
variable-wheel-gauge bogie travels on the standard-track
rails 22 in the up sloping section L. Therefore, even if
the variable-wheel-gauge bogie bounces, the locking projec-
tion 15B will not come off the locking recess 16 because
a vertical acceleration is in the range of about 0.3g to
0.5g and far less than the gravitational acceleration of
1g. However, since the axle springs 2 can be transversely
slightly displaced due to their rigidity, there is the
possibility that the wheels 9 move relative to the axle 4
and the components of the variable-wheel-gauge bogie chat-
ters and are abraded if the play of the extensions 17 of
the journal boxes 3 in the corresponding circular grooves
6 of the axles 4 is permitted. Therefore, the play of the
extensions 17 in the corresponding circular grooves 6 is
inhibited perfectly by the wedging action of the fastening
members 18 to solve the aforesaid problems.
When a train of a plurality of railroad cars pass the
wheel gauge changing track arrangement of Figs. 7A and 7B,
2178177
it is desirable to stop the drive motors 10 of the railroad
car traveling in a section of the track corresponding to
the wheel gauge changing track arrangement. The railroad
car may be provided with a sensor for detecting the wheel
gauge changing arrangement and supply of power to the
drive motors 10 may be stopped upon the detection of the
wheel gauge changing arrangement by the sensor.
The operation of the first embodiment when the
railroad car travels from the standard-track rails 22 of
L0 the standard track to the narrow-track rails 21 of the
narrow track is reverse to the foregoing operation of the
same and hence the description of the former will be
omitted.
In this embodiment, a stack of a plurality of height
1> adjusting shims 50 are fastened to the sliding surface 3a
of the journal box 3 with screws as shown in Figs. 2, 3,
4 and 6. The diameter of each wheel 9 decreases as the
wheel 9 is abraded and the distance between the sliding
surface 3a of each journal box 3 and the car support rail
20 26 decreases. Therefore, some of the shims 50 are removed
according to the reduction of the diameter of the wheel
9 to compensate a reduction in the distance between the
sliding surface 3a of the journal box 3 and the car
support rail 26.
25 Although the entire length of the car support rails
26 is extended in a horizontal plane and the sloping
sections L are formed in sections of the narrow-gauge
track and the standard-gauge track continuous with the
wheel gauge changing rails 23 of the wheel gauge changing
30 track in this embodiment, the respective rails 21, 22 and
23 of the narrow-gauge track, the standard-gauge track and
the wheel gauge changing track may be extended in a
horizontal plane and sloping sections may be formed in the
car support rails 26.
35 Maintenance work including changing the wheels 9 and
the taper roller bearings 8 will be greatly simplified when
the locking block 13 is detachable from the axle sleeve 7,
2178177
21
and the section of the axle sleeve 7 in which the locking
block 13 is mounted on the axle sleeve 7 is formed in an
outside diameter smaller than the inside diameter of the
taper roller bearing 8.
Since the wheels 9 are guided by the guide rails 24
biased by the springs 25 so as to be in contact with the
side surfaces of the wheels 9, the wheels 9 can be very
smoothly shifted according to the variation of the rail
gauge of the wheel gauge changing track for wheel gauge
adjustment.
A variable-wheel-gauge bogie in a second embodiment
of the present invention will be described hereinafter
with reference to Figs. 8 to 24. The variable-wheel-gauge
bogie in the second embodiment is similar in construction
to the variable-wheel-gauge bogie in the first embodiment
and hence only components and arrangements of the
variable-wheel-gauge bogie different from those of the
variable-wheel-gauge bogie in the first embodiment will
be described.
Referring to Figs. 8, 9 and 11, a tubular locking
block 13 is fixedly united to on end of an axle sleeve 7
on the side of the end of an axle 4. As best shown in
Fig. 11, male splines are formed in a portion of the axle
sleeve 7, and female splines mating with the male splines
are formed on the locking block 13 to inhibit the rotation
of the axle sleeve 7 and the locking block 13 relative to
each other. Since the locking block 13 is supported on
the journal box 3 so that the locking block 13 is unable
to rotate, which will be described later, the axle sleeve
7 is unable to rotate. The locking block 13 is fastened
to the axle sleeve 7 with a nut 28 as shown in Fig. 8 so
that the locking block 13 is unable to move axially
relative to the axle sleeve 7.
The locking block 13 is contained in the journal box
3. As shown in Fig. 11, the locking block 13 has a
horizontal, load bearing upper surface 13a in contact with
the upper wall of the journal box 3 to take the weight of
21'8177
a truck frame through the journal box 3, and sliding side
surfaces 13b in contact with a sliding side guide surfaces
formed in the journal box 3.
As shown in Figs. 8 and 10, a pair of conical locking
projections 15A and 15B project from the upper surface 13a
of the locking block 13. The conical locking projections
15A and 15B are spaced apart by a predetermined distance.
The center distance between the conical locking projec
tions 15A and 15B is equal to half the difference between
a broad rail gauge and the standard rail gauge. More
concretely, in this embodiment, the broad rail gauge,
i.e., a standard rail gauge, is l435 mm and the narrow
rail gauge is 1067 mm. Therefore, the center distance
between the conical locking projections 15A and 15B is
1~ (l435 - 1067)/2 = l84 mm.
A locking hole 32 and an escape hole 33 are formed in
the upper wall of the journal box 3. The distance along
the axis of an axle 4 between the locking hole 32 and the
escape hole 33, i.e., the center distance, is equal to the
center distance between the conical locking projections
15A and 15B. When the conical locking projection 15A or
15B is fitted in the locking hole 32, the axle sleeve 7
is unable to move axially. The positional relation
between the conical locking projections 15A and 15B and the
2~ locking hole 32 is determined so as to meet the following
conditions. The wheel 9 is at a position indicated by
continuous lines in Fig. 8 corresponding to the narrow
rail gauge when the conical locking projection 15A is
fitted in the locking hole 32, and the wheel 9 is at a
position indicated by alternate long and two short dashes
lines in Fig. 8 corresponding to the broad rail gauge when
the conical locking projection 15B is fitted in the
locking hole 32. The conical locking projection 15A is
received in the escape hole 33 when the conical locking
3~ projection 15B is fitted in the locking hole 32. The
diameter of the escape hole 33 is far greater than the
conical locking projection 15A.
217817'i
23
Referring to Figs. 12 and 13, each of the conical
locking projections 15 (the reference numeral 15 will be
used to indicate both the conical locking projections 15A
and 15B inclusively) has a cylindrical lower portion 15a
and a conical head portion 15b. The cylindrical lower
portion 15a has a height h and a uniform diameter through
the height h. The conical head portion 15b is tapered
upward. The locking hole 32 of the journal box 3 has a
lower section 32a of a height h and an upper section 32b.
The diameter of the lower section 32a is slightly greater
than that of the cylindrical lower portion 15a, and the
diameter of the upper section 32b is far greater than that
of the lower section 32a.
A vibration isolating unit 34 for the conical locking
projection 15 is fitted in the upper section 32b of the
locking hole 32. The vibration isolating unit 34 comprises
an outer ring 35 detachably fixed to the circumference of
the upper section 32b, an annular rubber vibration isolator
35 fixed to the inner circumference of the outer ring 35,
and an inner ring 36 fixed to the inner circumference of
the rubber vibration isolator 37. The outer ring 35 is
provided with an inner flange 35a serving as a retainer
for retaining the inner ring 36 or the rubber vibration
isolator 37, and an outer flange 35b. The outer flange
35b is fastened detachably to the journal box 3 with screws
39.
The vibration isolating unit 34 in a natural state,
when none of the conical locking projections 15 is fitted
in the locking hole 32, a predetermined clearance is
formed between the inner ring 36 or the rubber vibration
isolator 37, and the inner flange 35a as shown in Fig. 13.
Referring to Figs. 14, 15 and 16, an end stopper 40
projects from each end of an axle 4, and sliding members
41 extend perpendicularly to the axis of the axle 4 from
the opposite sides of the end stopper 40. Each sliding
member 41 has a taper upper end portion 41a. An opening
42 (Fig. 16) is formed in a side wall 3a of a journal box
2178177
24
3, and a vibration isolating unit 43 for the sliding
member 41 is fitted in the opening 42. The vibration
isolating unit 43 comprises a box 44 detachably fitted in
the opening 42, a rubber vibration isolator 45 and a liner
46 fixed to the rubber vibration isolator 45. The box 44
is provided with a recess opening into the journal box 3,
and the rubber vibration isolator 45 is fastened to three
surfaces defining the recess of the box 44.
A.sliding groove 47 is formed in the side wall 3a of
the journal box 3 so as to extend into the recess of the
box 44. The upper end of the sliding groove 47 opens into
the recess of the box 44. The sliding member 41 is fitted
slidably in the sliding groove 47 so that the taper upper
end portion 41a of the sliding member 41 is in contact with
the liner 46 of the vibration isolating unit 43. As shown
in Fig. 16, the upper surface 42a and the lower surface 42b
of the opening 42 serve as an upper stopping surface and
a lower stopping surface for the vibration isolating unit
43. The operation of the second embodiment will be de-
scribed hereinafter on an assumption that the railroad car
travels from the narrow-track rails 21 of the narrow track
to the standard-track rails 22 of the standard track.
The variable-wheel-gauge bogie is in the geometry
shown in Figs. 8, 12, 14 and 15 while the railroad car is
traveling on the narrow-track rails 21 and the conical
locking projections 15A are fitted in the locking holes
16, respectively. Drive motors, not shown, drive the
wheels 9 to drive the railroad car for traveling.
Immediately after the variable-wheel-gauge bogie has
entered the down sloping section L of the narrow-track
rails 21, the sliding surfaces 3a of the journal boxes 3
come into contact with the car support rails 26, and then
the journal boxes 3 are kept in a substantially horizontal
plane by the car support rails 26 while the axles 4 and
the axle sleeves 7 move downward relative to the journal
boxes 3 according to the inclination of the down sloping
section L. Consequently, the sliding members 41 shown in
2178177
?J
Figs. 14 to 16 move downward along the sliding grooves 47,
and the conical locking projections 15A shown in Figs. 8
and 12 come off the corresponding locking holes 32 to
allow the axle sleeves 7 to move axially. The axle
sleeves 7 are allowed to move axially before the
variable-wheel-gauge bogie reaches the terminal end of the
down sloping section L at the latest. Then, the
variable-wheel-gauge bogie starts traveling on the wheel
gauge changing rails 23 of the wheel gauge changing track
gradually widening toward the standard track. Then, the
wheels 9 are guided by the guide rails 24 biased toward
the wheels 9 by the springs 25 as the wheels roll on the
wheel gauge changing rails 23, so that the wheels 9 are
shifted gradually outward together with the associated axle
1~ sleeves 7 on the axles 4. When the variable-wheel-gauge
bogie arrives at the terminal end of the wheel gauge chang-
ing rails 23, the outer ends of the sleeves 7 come into
contact with the corresponding stoppers 40, and the axle
sleeves 7 are stopped. In this state, the distance between
the pair of wheels 9 on each axle 4 is equal to the
standard rail gauge, and the locking projections 15B are
located opposite to the locking holes 32, respectively.
Since the truck frame of the variable-wheel-gauge bogie
is supported through the journal boxes 3 on the car
support rails 26 while the variable-wheel-gauge bogie is
traveling on the wheel gauge changing rails 23 or on
sections of the narrow-track rails 21 or the standard track
rails 22 near the ends of the wheel gauge changing rails
23, the wheels 9 and the axle sleeves 7 are lightly
loaded, and hence the axle sleeves 7 are able to slide
lightly along the axles 4 according to the variation of
the rail gauge of the wheel gauge changing track.
Then, the variable-wheel-gauge bogie moves from the
wheel gauge changing rails 23 to the standard-track rails
22. While the variable-wheel-gauge bogie is traveling in
the up sloping section L of the standard-track rails 22,
the axles 4 and the axle sleeves 7 move upward relative
21p177
to the journal boxes 3, the sliding members 41 shown in
Figs. 14 to 16 slide upward along the sliding grooves 47,
the conical head portions 15b of the conical locking
projections 15B enter the vibration isolating units 43,
respectively, the conical locking projections 15B are
fitted in the locking holes 32 of the journal boxes 3,
respectively, and the conical locking projections 15A enter
the escape holes 33. Referring to Fig. 12, when the
conical locking projection 15B enters the corresponding
locking hole 32, the conical head portion 15b of the
conical locking projection 15B passes the lower section
32a of the locking hole 32 and enters the upper section
32b, and the conical surface of the conical head portion
15b comes into contact with the inner ring 36 of the
vibration isolating unit 34 to push the inner ring 36 up.
Consequently, the rubber vibration isolator 37 is com-
pressed and the large resilience of the compressed rubber
vibration isolator 37 acts on the side surface of the
conical locking projection 15B.
The mode of engagement of the taper upper end portion
41a of the sliding member 41 with the vibration isolating
unit 43 is similar to that of engagement of the conical
head portion 15b of the conical locking projection 15B
with the vibration isolating unit 34; the taper upper end
portion 41a pushes the liner 46 up as the same moves up
to compress the rubber vibration isolator 45.
Since the conical locking projection 15B has the
conical head portion 15b, the conical locking projection
15B can be surely fitted in the locking hole 32 even if
the conical locking projection 15B and the locking hole
32 are dislocated slightly relative to each other.
Thus, the axle sleeve 7 is restrained from axial
sliding movement and the distance between the pair of
wheels 9 on each axle 4 is fixed at the standard gage.
Since the conical locking projection 15B is fitted in the
locking hole 32 by the weigh of the truck frame, the
conical locking projection 15B will never come off the
21781'~'~
locking hole 32 accidentally. Since dynamic shocks due to
the play of the conical locking projection 15B in the
locking hole 32 during traveling are absorbed by the
rubber vibration isolator 37, the abrasion of the compo-
nent parts can be effectively prevented and high traveling
stability can be secured. Particularly, since the rubber
vibration isolator 37 is deformed elastically beforehand
when the conical locking projection 15B is fitted in the
locking hole 32, the dynamic shocks that occur during
travel due to the play can be very effectively absorbed,
and the relative movement of the j ournal box 3 and the axle
sleeve 7 can be effectively suppressed.
Since the cylindrical lower portion 15a of the conical
locking projection 15B is received in the lower section 32a
of the locking hole 32 having a diameter substantially
equal to that of the cylindrical lower portion 15a when
the conical locking projection 15B is fitted in the locking
hole 32, the area of contact between the surface of the
cylindrical lower portion 15a and the side surface of the
lower section 32a is comparatively large, which is
advantageous in strength.
There is the possibility, due to some causes, that the
conical head portion 15b of the conical locking projection
15B bites the inner ring 36 of the vibration isolating unit
?5 34 and deforms the rubber vibration isolator 37 excessively
when the conical locking projection 15B moves into or when
the same moves out of the locking hole 32. This embodiment
uses the inner flange 38a of the outer ring 35 disposed
above the rubber vibration isolator 37 as an upper stopper,
and a portion of the journal box 3 under the rubber vibra-
tion isolator 37 as a lower stopper to prevent the exces-
sive deformation of the rubber vibration isolator 37.
Since the sliding member 41 projecting from the end
stopper 40 is fitted in the sliding groove 47 formed in the
journal box 3 and the vibration isolating unit 43, the
journal box 3 and the axle 4 are maintained in a fixed
positional relation and hence the positional relation
217817'i
between the locking hole 32 of the journal box 3 and the
axle 4 is fixed. Accordingly, the conical locking projec-
tion 15 fixed to the axle sleeve 7 can be surely fitted in
the locking hole 32.
The operation of the second embodiment when the rail-
road car travels from the standard-track rails 22 of the
standard track to the narrow-track rails 21 of the narrow
track is reverse to the foregoing operation of the same- and
hence the description of the former will be omitted.
Although the entire length of the car support rails
26 is extended in a horizontal plane and the sloping
sections L are formed in sections of the narrow-gauge
track and the standard-gauge track continuous with the
wheel gauge changing rails 23 of the wheel gauge changing
track in this embodiment, the respective rails 21, 22 and
23 of the narrow-gauge track, the standard-gauge track and
the wheel gauge changing track may be extended in a
horizontal plane and sloping sections may be formed in the
car support rails 26.
Since the wheels 9 are guided by the guide rails 24
biased by the springs 25 so as to be in contact with the
side surfaces of the wheels 9, the wheels 9 can be very
smoothly shifted according to the variation of the rail
gauge of the wheel gauge changing track for wheel gauge
adjustment.
Fig. 18 shows vibration isolating unit 34 for conical
locking projection, in a modification. The vibration
isolating unit 34 shown in Fig. 18 has an annular plate
spring 51 having a V-shaped section and set along the
circumference of the locking hole 32. The plate spring 51
has a flange 51a detachably fastened to the journal box 3
with screws 52. Longitudinal slits 53 are formed in the
annular plate spring 51, and a recess 54 is formed in the
circumference of the locking hole 32 to allow the elastic
deformation of the annular plate spring 51.
The annular plate spring 51, similarly to the rubber
vibration isolator 37 shown in Fig. 12, is elastically
2178177
2,
deformed by the conical locking projection 15 and applies
its resilience to the conical locking projection 15. The
vibration isolating unit 34 employing the annular plate
spring 51 is simpler in construction than the vibration
isolating unit 34 shown in Fig. 12, can be easily fabricat-
ed and assembled, and is superior in durability to the
vibration isolating unit 34 shown in Fig. 12.
Fig. 19 shows a vibration isolating unit 34 for
conical locking projection, in another modification. The
vibration isolating unit shown in Fig. 19 comprises a wedge
ring 57 fixedly fitted in the upper section of the locking
hole 32, a cover 55 detachably fastened to the journal box
3 with screws 56 so as to cover the upper open end of the
upper section of the locking hole 32, and a Belleville
spring 58 disposed between the upper surface of the wedge
ring 57 and the cover 55 to bias the wedge ring 57
downward. Since the Belleville spring 58 is a means
simply for biasing the wedge ring 57 downward, the same
may be substituted by an elastic rubber ring.
The conical portion of the conical locking projection
15 comes into engagement with the inner circumference of
the wedge ring 57 when the conical locking projection 15
is fitted in the locking hole, and the wedge ring 57
biased downward by the Belleville spring 58 comes into
close contact with the conical locking projection 15 by its
own wedging action. Thus, the conical locking projection
15 can be held in the locking hole 32 substantially
without any play. The wedge ring 57 is provided with a
slit 59 as shown in Fig. 20 in order that the wedge ring
57 can be elastically distorted and easily fitted in the
locking hole 32. Figs. 21 and 22 show vibration
isolating unit 43 for sliding member, in a modification.
This vibration isolating unit 43 comprises a cover 61
detachably attached to the side surface of the journal box
3 so as to cover an opening 60 formed in the side wall of
the journal box 3, and a U-shaped spring plate 62 having
a V-shaped cross section as shown in Fig. 22 and fitted
218177
in the opening 60. A recess 63 similar to the recess 54
(Fig. 18) is formed in the opening 60. The operation of
the vibration isolating unit 43 for sliding member,
employing the plate spring 62 is substantially the same
5 as that of the vibration isolating unit 34 for conical
locking projection.
Figs. 23 and 24 show modifications of the sliding
member 41 and the guide cavity. Brackets 65 projects from
the opposite ends of the end stopper 40, respectively, a
10 sliding pin 66 is set in an upright position on each
bracket 65. The upper end portion of the sliding pin 66
is tapered in a conical shape. Guiding through holes 67
are formed in the journal box 3 to guide the sliding pins
66 for vertical movement. A vibration isolating unit 68
15 for sliding member is disposed in an upper portion of the
through hole 67. The vibration isolating unit 68 is
entirely the same in construction as the vibration isolat-
ing unit 43 for conical locking projection, shown in Fig.
12; the vibration isolating unit 68 comprises an outer
20 ring, a rubber vibration isolator and an inner ring.
Naturally, the vibration isolating unit 68 for sliding
member may employ a plate spring having a V-shaped cross
section similar to the plate spring 51 shown in Fig. 18.
While the presently preferred embodiments of the
2~ present invention have been shown and described, it is to
be understood that these disclosures are for the purpose
of illustration and that various changes and modifications
may be made without departing from the scope of the
invention as set forth in the appended claims.
