Note: Descriptions are shown in the official language in which they were submitted.
CA 02114119 2003-10-O1 -
Drilling Machine For Railroad Rail
Technical Field
The present invention relates to a drilling machine that drills boltholes for
the
fastening of connecting plates on abutting railroad rails during the laying
and repair of
railroad track.
Prior Art
Connecting plates are positioned for reinforcement on railroad rails and
fastened
to them with bolts during the laying of railroad track and the replacement of
worn track.
During this process, a specified number of boltholes are drilled in the middle
part of the
rail, but since the drilling height and pitch of the bolt insertion holes on
the connecting
plates are predetermined for each type of rail, holes must be drilled in the
rails to match
the bolt insertion holes on the connecting plates.
The conventional method of drilling boltholes in railroad rails was to first
determine the position of the holes to be drilled in each rail and then make
punch marks,
after which a drill was directed to the marks and the holes were drilled.
Marking and
punching each rail was tedious and handling the heavy drilling machine was a
cumbersome' task. There was thus a demand for a drilling machine capable of
the simple
and rapid operation needed when changing railroad rails in emergencies.
The present invention, devised out of the need to address such drawbacks of
prior
art, has for its object to provide a drilling machine for railroad rail that
requires none of
the marking and punching of conventional rail drilling procedures, and that
permits
simple and rapid adjustment of the drilling machine on, and drilling of, all
types of rail.
In accordance with this invention a drilling machine for drilling a railroad
rail
comprises a rotating drive source, a cutter for drilling, which is attached to
the rotating
drive source, a main body case housing the rotating drive source, and an
output shaft
CA 02114119 2003-10-O1
extending outwardly from the main body case. Slide shafts are positioned on
sides of the
main body case, and the rotating drive source is centered between those slide
shafts. A
clamp arm is provided and has a support shaft permitting the clamp arm to move
freely.
A catch frame is secured on two output-shaft ends of the slide shafts,
opposite the clamp
arm, and a clamping means, including a gripping surface of the catch frame and
a hook
member, below the clamp arm, opposed to the gripping surface, grips a railroad
rail
crosswise and from both sides. Also provided is an upper-rail support facing
inward and
secured on the inside of the gripping surface of the catch frame, and a height
gauge, with
a through-hole drilled approximately in its center, bolted to the gripping
surface, with
two medial-rail supports juxaposed on it and separated by a gap. Upward rail
supports
are threaded in screw holes in the height gauge to position them on the height
gauge
according to designated drilling heights of boltholes for different types of
railroad rail. A
pitch gauge, on which numerous countersinks are positioned in relation to one
of an end
of and a specified spot on the railroad rail so as to correspond to a pitch
designated for
boltholes of different types of railroad rail, is readily removably mounted,
before drilling,
on an upper surface of the railroad rail. A clamp screw, having a rotating
handle, is
threaded vertically down through a tapped cylinder on an upper end of the
clamp arm and
over an axial center of the cutter; a lower end of the clamp screw being
aligned with a
specific countersink on the pitch gauge and tightened to secure the clamp
means in
position, significant pressure being perpendicularly maintained from above and
below as
well as in a horizontal direction on the railroad rail by the clamp means. A
retaining
plate is secured on back ends of the slide shafts, and a link mechanism,
having a rotating
handle, for advancing and retracting the main body case using the retaining
plate as a
support point, is positioned between the main body case and the retaining
plate. The
cutter is mounted on the output shaft so that it can be advanced by rotation
of the rotating
handle of the link mechanism to drill a bolthole in the middle of the rail at
a specified
height and a specified pitch.
CA 02114119 2003-10-O1
Brief Description Of The Figures
Figure 1 is an exploded perspective view of the drilling machine of the
present
invention.
Figure 2 is a side view of the clamp means of the present invention.
Figure 3 shows drawings describing the clamp configuration of the clamp means
shown in Figure 2 on the railroad rail.
Figure 4(a) shows a perspective drawing of the complete drilling machine of
the
present invention as well as its positioning relative to the pitch gauge
mounted on a
conventional rail; Figure 4(b) is a side view of a railroad rail showing the
relative
positioning of boltholes drilled in the middle part of the rail.
Figure 5 is a perspective view of the height gauge of the present invention.
Figure 6 is a perspective view of the complete drilling machine of the present
invention showing its positioning relative to the pitch gauge mounted on a
railroad rail of
the Shinkansen (popularly referred to as the Japanese "Bullet Train").
Figure 7 is a longitudinal section of the cutter mount portion of the drilling
machine of the present invention.
Description Of The Invention
The present invention, a drilling machine for railroad rail, is of a
configuration in
which the rotating drive source 3 of a cutter for drilling 2 is housed in a
main body case 1
and is secured in such a way that output shaft 4 extends outward and slide
shafts 5, S are
positioned along the sides of main body case 1 with rotating drive source 3
centered
between them; a clamp arm 7 is provided with a support shaft permitting
unobstructed
movement opposite a catch frame 6, which is secured on the two output shaft
ends Sa, Sa
of slide shafts 5, S; a clamping means is configured by a gripping surface 6a
of catch
frame 6 opposite twin-timed hook member 7a below clamp arm 7 to grip a
railroad rail 8
crosswise and from both sides; an upper rail support 9c facing inward is
secured on the
inside of gripping surface 6a of catch frame 6, and a height gauge 10 with
a.through-hole
11 drilled approximately in its center is bolted to the same surface; two
medial rail
.. . . .. . ~ 02114119 2003-10-O1 , , . . .. .
supports 9a, 9a are juxtaposed on height gauge 10 with a gap between them, and
various
screw holes 12, 12, etc. into which upward rail supports 9b, 9b can be
threaded to
position them on height gauge 10 according to the designated drilling heights
of boltholes
13 for each type of railroad rail are provided on height gauge 10; a pitch
gauge 20, on
which numerous countersinks 21, 21, etc. are positioned in relation to the end
of, or a
specified spot on, railroad rail 8 SO as to correspond to the pitch designated
for the
boltholes 13 of each type of railroad rail, is mounted before drilling on the
upper surface
of the railroad rail 8 to be drilled so as to be readily removable; a clamp
screw 14 having
a rotating handle 14a is threaded vertically down through a tapped cylinder 7b
on the
upper end of clamp arm 7 over the axial center of cutter 2; the lower end 14c
of clamp
screw 14 is aligned with a specific countersink 21 on pitch gauge 20 and
tightened to
secure the clamp means in position, and significant pressure is
perpendicularly
maintained from above and below as well as in a horizontal direction on
railroad rail 8 by
the clamp means; retaining plate 15 is secured on the back ends of slide
shafts 5, 5; a link
mechanism 16 for advancing and retracting main body case 1 using retaining
plate 15 as
a support point and having a rotating handle 16a is positioned between main
body case 1
and retaining plate 15; and cutter 2 mounted on output shaft 4 is advanced by
rotation of
the handle of link mechanism 16 to drill a bolthole 13 in the middle of the
rail 8a at a
specified height and a specified pitch.
In Figure 1, the main body case is denoted by 1. Rotating drive source 3 is
secured by the electric motor of hole-drilling cutter 2 in main body case 1.
Output shaft 4
of rotating drive source 3 extends outward from main body case 1. As shown in
the
expanded view of Figure 7, in the mounting of cutter 2, a center pin 4c is
inserted against
coiled spring 4b into the inner cavity of output shaft 4. Center pin 4c is
secured through
0-ring 4d by the matching threads of center pin guide 4a. Cutter 2 is secured
by
tightening its threaded inner portion over the threaded portion provided on
the exterior of
the front end of output shaft 4.
Cutter 2 is capable of drilling with high efficiency through a railroad rail
with a
metal borer having a blade on the outer perimeter of the front end of a
cylinder. Although
an engine drive or the like is suitable as rotating drive source 3, the
present embodiment
employs a motor drive. Cutting oil is supplied from a lubricant tank 31
positioned on the
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back of main body case 1 via a tube 31a to the inside of output shaft 4.
During drilling,
cutting oil is forced into the forward perimeter of cutter 2 by center pin 4.
A pair of pliers
30 is used to remove cores that have not been successfully ejected from cutter
2.
The top of main body case is covered by a cover la, which is secured by
screws. On
top of cover la is positioned switch 23a and control box 23, to which power
cord 23b is
connected.
On both sides of main body case 1 are secured slide shafts 5, 5, parallel with
and
centered about output shaft 4. The output shaft ends of slide shafts S, 5 have
threaded
portions Sa, 5a, which are anchored with nuts in through-holes 6c, 6c of catch
frame 6,
which in turn is shaped roughly like the letter "U" when viewed from the side
but positioned
with the open side facing downward and having a lengthwise gap in its lower
middle portion
[as viewed from main body case 1].
Clamp arm 7 is supported by a support shaft 22 allowing it to rotate freely in
the
lengthwise gap in the middle portion of catch frame ~6. A means of clamping is
configured
by opposing gripping surface 6a on catch frame 6 and hook member 7a on the
bottom of
catch arm 7 to cross clamp railroad rail 8 on two sides. However, hook member
7a is
formed with two tines (not shown) to keep from interfering with the advance of
cutter 2,
described further below.
,A single upper rail sup~rt 9c is secured facing inward on the upper middle
inner
section of gripping surface 6a of catch arm 6. Height gauge 10 is secured
below upper rail
support 9c so as to be readily detachable. As shown in Figures 1 and 2, height
gauge 10 is
secured by inserting bolts 10c, 10c, etc. from the outer side of gripping
surface 6a through
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;;
insertion holes 6b, 6b, etc. drilled in four spots on gripping plate 6a on
catch frame S and
tightening the bolts into threaded holes 10a, 10a, etc. tapped in the four
comers of height
gauge 10.
As shown in Figure 5, in addition to threaded holes 10a, IOa, etc. used to
secure
height gauge 10, medial rail supports 9a, 9a are secured on the lowermost
portion of height
gauge 10, parallel to each ether and separated by a gap, and through-hole 11
is drilled in
approximately the center of gauge 10.
Numerous screw holes 12, 12, etc. corresponding to the different types of
rails are
else positioned on height gauge 10 so that its left side is symmetrical to its
right. A type of
rail is indicated for each of screw hales 12, 12, etc. Prior to drilling, two
upward rail
supports 9b, 9b are secured in a parallel manner by threading bolts 9d, 9d in
the screw holes
12, 12 corresponding to the type of rail to be cut.
As shown in Figure 2, clamp screw 14 having a relating handle 14a is threaded
vertically down through tapped cylinder 7b positioned on the upper end of
clamp arm 7 over
the axial center of cutter 2 which advances perpendicularly with respect to
railroad rail 8.
lgy aligning the lower end 14c of clamp screw 14 with a specific countersink
21 an above-
mentioned pitch gauge 20 and tightening down clamp screw 14, as well as
rotating clamp
arm 7 about support shaft 22 so that pressure is maintained on the middle part
of the rail 8a
by rotating hook member 7a, significant pressure is perpendicularly maintained
from above
and below and in a horizontal direction on railroad rail 8.
As shown in Figure 2, when railroad rail 8 is clamped in this manner, upward
rail
supports 9b, 9b support the upper bulge of the rail 8b against pressure
applied by the
6
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tightening of clamp screw 14, and the support point of the upper bulge of the
rail 8b is at a
fixed distance H2 from the center of drilling 2c.
In this manner, the drilling height H 1 from the bottom of railroad rail 8 is
determined
by the clamping position of the upper bulge of the rail 8b.
In this method of clamping, in the positions and directions of support shown
by
arrows in Figure 3, the middle part of the rail Sa is horizontally supported
at two point by
medial rail supports 9a, 9a; the upper bulge of the rail 8b is horizontally
supported at two
points by upward rail supports 9b, 9b; and the side of the upper part of the
rail 8c is
supported at one central point by upper rail support 9c. The various lengths
of medial rail
supports 9a, 9a, upward rail supports 9b, 9b, and upper rail support 9c are
such that
gripping surface 6a of catch arm 6 is held in uniform vertical contact with
railroad rail $.
As shown in Figure 2, a vertical line passing through the center of clamp
screw 14
and projected downward through its lower end 14c is approximately equidistant
from the
contact points with the rail of medial rail supports 9a and upward rail
supports 9b, permitting
stable tightening of clamp screw 14.
As shown in Figure 4, end face 20c of pitch gauge 20 is aligned with end face
8d of
railroad rail 8 when mounting pitch gauge 20 on the upper surface of railroad
rail 8. Pitch
gauge 20 comprises a clamping strip 20a that can be fit over the width of
railroad rail 8 and
is attached on one end of a flat plate. A screw 20b having a winged dghtener
is positioned
on one side of clamping strip 20a, permitting screw 20b to be tightened
against the side of
the upper part of the rail 8c. Countersinks 21, 21, etc. are positioned on the
surface of the
flat plate of pitch gauge 20 at distances measured from end surface 20c and
corresponding to
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CA 02114119 2003-10-O1
the drilling positions of boltholes 13. Countersinks 21 are positioned
crosswise in pairs so
that the lower end 14c of clamp screw 14 can be tightened down over railroad
rail 8 on
either of the countersinks in a pair.
When the railroad rail to be repaired is a Shinkansen rail 8', a pitch gauge
for use on
Shinkansen track is first made by abutting the end surfaces of two of the
above-described
pitch gauges 20. The center 29c of the new pitch gauge is then aligned with
the cracked
portion 29 of the rail and the gauge seated on the rail. Countersinks 21, 21,
etc. are also
provided in the same manner on pitch gauge 20' for use on Shinkansen rails,
which is
clamped in a manner identical to that described above.
Retaining plate 15 is secured on the rear ends of slide shafts 5, 5 to the
rear of main
body case 1. Link mechanism 16 with attached rotating handle 16a is secured
between
retaining plate 15 and main body case 1.
Main body case 1 can be moved forward and backward by rotating the handle of
link
mechanism 16. Boltholes 13 are drilled at specified height and pitch in the
middle part of
the rail 8a by advancing cutter 2, mounted on output shaft 4, between the
tines of hook
member 7a of clamp arm 7. Handles 25, 26, used to transport the drilling
machine, are
mounted behind main body case 1 and on the front of clamp case 6,
respectively.
As part of the drilling process, upward rail supports 9b, 9b are secured in
the
threaded holes 12, 12 appropriate for the type of rail in order to set the
drilling height of the
bolthole 13 to be drilled. Clamp screw 14 is then tightened onto one of the
countersinks 21
on pitch gauge 21 which has been mounted on top of railroad rail 8 and a
bolthole 13 is
drilled in the middle part of the rail 8a by the rotating drive of cutter 2
when the cutter is
8
~
~a
advanced. Clamp screw 14 is then released and retightened on the next
countersink 21 and
the drilling repeated in this manner a specified number of times to make
boltholes 13 of
specified pitch and height.
After drilling a hole, the core in cutter 2 is ejected by center pin 4 which
is driven by
coiled spring 4b, but spring-powered ejection is sometimes incomplete due to
abrasion with
cutter 2 and the like. At such times, the ends of pliers ~0 are inserted from
the exterior
through through-hole 11 to grip the outer edge of the core in cutter 2 and
extract it.
P~tential for l~dustcial Applicati~n
As described above, in the railroad rail drilling machine of the present
invention the
upper bulge of the rail is secured by the specific positioning of the height
gauge
corresponding to the type of rail to be drilled and a pitch gauge is mounted
on a specific
position on the rail. 13y simply tightening a Clamp screw onto a countersink
on the pitch
gauge, the drilling machine is firmly and perpendicularly secured in position
from above and
below as well as horizontally, and the pitch and height of the bolthole
drilling position are
set. Once a drilling machine of this type has been clamped in position,
drilling is carried out
by simply rotating a handle to advance a rotating cutter.
Accordingly, drilling can be completed in an extremely easy and rapid manner
without marking and punching each position on the rail.
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