Note: Descriptions are shown in the official language in which they were submitted.
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Descriptlon
~p~aratus And Method For Forming An External_Guard
Member On A Hose
Technical Field
This invention relates generally to an
apparatus and method for forming an ex-ternal guard
member in situ on a hose and more particularly to an
apparatus and method for forming a spring steel wire
guard member about the exterior surface of a reinforced
hydraulic hose.
Back~round ~rt
Guard members for hoses, and in particular,
coiled wire protectors for high pressure hydraulic
hosesf are well known and generally referred to as
armored hose or hose having an armor guard. The guard
members are particularly useful on hydraulic hoses
installed on construction machinery, serving to pro-tect
such hoses from cuts, abrasion, and crushing.
Generally, the guard member is a coiled steel wire or
band having an inside diameter larger than the outside
diameter of the hose. The guard member thus encircles
the hose in a spaced relationship to permit the hose to
flex freely within the guard member.
Spring steel wire is highly desirable as a
material for guard members. However, heretofore it has
been necessary to preform the spring steel wire on a
coiling machine having a solid mandrel, cut the
preformed coil to a predetermined length, and then
slide the preformed coil onto a length of hose having a
fitting assembled on only one end~ The preformed coil
was installed over the second end of hose, the second
end being the end opposite the assembled end. After
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installation of the spring steel coil on the hose, it
was necessary to compress the coil longitudinally along
an elongate central axis of the hose, in a direction
toward the first or assembled hose endl to expose a
length of hose near the second end sufficient for the
application of a temporary clamp. After clamping,
assembly of the hose was completed by installing a
fitting on the second hose end. Finally, the temporary
clamp was released and the guard member allowed to
expand back to the original uncompressed length.
As may be easily appreciated, the above method
for constructing an armored hose presents a number of
problems. First, it is difficult to install, clamp,
and compress the spring coil member on a partially
assembled hose. Secondly, it must be determined in
advance which hoses are to receive the protective guard
member since the coil spring guard member could not be
installed on a hose after fittings were installed on
both ends. Thus, it has been necessary to interrupt
the hose assembly process after a fitting was installed
on only a first end of the hose.
In response to the above problems, an
alternate guard member construction is often used. In
the alternate construction, an elongated soft steel
strap or band is used for the guard member in lieu of
the aforementioned spring steel wire. The soft steel
strip can be easily formed in the shape of a coil
without the aid of a solid mandrel and can therefore be
formed in situ on a hose. An assembled hose, -that is a
hose having fittings installed on both ends, is
positioned in an open die, and the soft steel strip is
formed in a coil around the hose. However, easy
formability of the soEt steel strip material also
yield~ a guard member that may also be easily crushed
in use. A guard member that has been crushed or
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otherwise deformed may restrict the: flow capacity of the hose
and will generally abraid the hose surface adjacent the crushed
zone resulting i.n premature hose failure.
The present invention is directed to overcoming one or
more of the problems as set forth above by providing an apparatus
and method for forming -the preferred spring steel wire guard
member in situ on a hose having fittings preasse~bled on both
ends.
Disclosure of The: Invention
_
In accordance with.one aspect of the present invention,
there i5 provided in an apparatus for forming a guard member on
a hose, said apparatus having a frame, first means Eor suppor-ting
at least one of said guard member and said hose along a longi-
tudinal axis, and second means for feeding a continuous strand
of guard material from a supply source to said apparatus, the
improvement comprising: a forming head mounted on said frame
for forming a coil-shaped guard member circumferentially about
and radially spaced from said hose, said head having separable
first and second portions and a plurality of die members rotatably
mounted on respective ones of said first and said second portions
in arcuate positions which are spaced relative to each other, at
least two of said plurality of die members being mounted on said
first portion of the forming head at an e~ually radially spaced
predetermined first distance from said longitudinal axis, and
at least one of said plurality of die members being mounted on
said second portion of th.e forming head at a radially spaced
second distance greater than said predetermined Eirst distance
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from said longitudinal axis when said second portion is in an
abutting relationship with respect to said first portion; means
for selectively separating said first and said second portions;
and wherein said second means for feeding a continuous strand
of guard material includes a plurality of driven rollers for
propelling said continuous strand of guard material into pressure
contact with said plurality of die members and rotating said
formed coil-shaped guard member about said hose.
In another aspect of the present invention, there is
provided an apparatus for forming an external guard member on
a hose, comprisin~: a frame; first means for supporting at
least one of said guard member and said hose along a longitudinal
axis; a forming head havïng a first portion and a second portion,
said first portion being attached in a fixed position on said
frame and said second portion being moveably mounted on said
frame, and a plurality of die members rotatably mounted in
respective ones of said first and second portions wherein at
least two of said plurality of dle members mounted in the first
portion of said forming head are equally radially spaced at a
predetermined first distance from said longitudinal axis and
at least one of said plurality o:E die members mounted in the
second portion of said forming head is radially spaced from
said longitudinal axis at a distance equal to said predetermined
first distance and at least one of said remaining die members
mounted on said second portion is radially spaced from said
longitudinal axis at a predetermined second distance, said
second distance being greater than said first distance; means
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for movlng said second portion in a transverse direction with
respect to said longitudln~l axis between a first position at
which said first and second portions are spaced apa.rt and a
second position at which said first and second portions are
contiguous; and second means for feeding a continuous strand
of guard materi.al from a supply source to said forming head in
a transverse direction with respect to said longitudinal axis.
According to a further aspect of thQ invention, there
is provided a method for forming an external guard member on a
hose, comprising: posltlonlng s-ald hose in a formlng head
having separable first and second portions; moving at least one
of said first and second portions to an abutting position with
the other of said first and second portions; feeding a con~
tinuous strand of guard material from a supply source to said
forming headi urging said guard material into pressure contact
with at least one die member in said forming head and forming
the guard material into a first coil shape having a first
predetermined diameter; subsequently urging said first formed
guard material in-to pressure contact with at least one
additional die memher in said forming head and forming said
guard material into a continuous spiral coil circumferentially
about and radially spaced from said hose, said contlnuous
spiral coil having a diameter greater than said first pre-
determined diameter; and, rotating and axially advancing said
formed spiral coil with respect to said hose.
Heretofore it has not been possible to form a spring
steel wire guard member about the exterior surface of a hose
having fittings attached at both ends. Due to the tendency of
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spring steel wire to "spring back" or return to an earlier
position when b.ent to a second position, it is necessary to
form spring steel wire by either over~ending or by pressure
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forming against a solid surface such as a mandrel~ ~he
present invention solves the problem of forming a
spring steel wire member abou-t a resilient member, such
as a hose, by providing an apparatus and method for
urging a continuous strand of guard material into a
first coil shape having a diameter less than the
desired final-formed diameter of the guard memberO As
a result of the unique two-piece split die arrangement
of the present invention, a hose having fittings
preassembled on each of the hose ends, can be placed
between the dies and, a~ter closing of the dies, a
spring steel wire guard member ~ay be formed about the
hose from one fitting end to the other.
Brief Descri~tion Of The Drawings
Fig. 1 is a front eleva-tional view of an
embodiment of the apparatus of the present invention.
Fig. 2 is a side view of an embodiment of the
apparatus of the present invention taken along the line
II-II of Fig. 1.
Fig. 3 is a partially-sectioned portion of the
side view of Fig. 2.
Fig. 4 is a partially-sectioned side view of
another portion of Fig. 2.
Fig. 5 is a partially-sectioned view of a
forming head of an embodiment of the present invention~
Fig. 6 is an elevational view of a die member
of an embodiment of the present invention taken along
the line VI-VI o Fig. 5.
Fig. 7 is an elevational view oE a roller of
an embodiment of the present invention taken along the
line VII-VII of F'ig. 5.
Fig. 8 is a side view of the roller of an
embodiment of the present invention taken along the
line VIII-VIII of Fig. 7.
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Fig. 9 is a sectional view of the apparatus of
an embodiment of the present invention taken along the
line IX-IX of Fig. 1.
Fiy. 10 is a partially-sectioned side view of
an embodiment of the present invention showing the
forming head in an open position.
Best Mode For Carrying Out The Invention
An apparatus for forming an external guard
member 12 on a hose 14 is generally indicated in Fig. 1
by the reference numeral 10. The apparatus 10 includes
a frame 16, a first means 18 for supporting at least
one of the guard member 12 or the hose 14, a forming
head 20, and a second means 22 for feeding a continuous
strand of guard material 24, (Fig. 2) from a supply
source such as a play-off reel, not shown, to the
apparatus 10 and more particularly to the forming head
20. As shown in Figs. 2 and 3, the apparatus 10 also
includes a third means 26 for cutting the strand of
guard material 24.
The second means 22 for feeding a continuous
strand of guard material 24 includes a plurality of
driven rollers 28 and a fourth means 30 for equally
urging the strand of guard material 24 into pressure
contact with each of the rollers 28. The driven
rollers 28 are synchronously driven in a normally
counterclockwise direction, as viewed in Fig. 3, by a
motor 290 The fourth means 30 for equally urging the
strand of guard material 24 into pressure contact with
the driven rollers 28 includes a plurality of rollers
32 each mounted in a pair of vertically adjustable
journals 34 on the frame 16. Each of the rollers 32
are positioned vertically above one of the driven
rollers 28 forming a plurality of mating pairs of
driven rollers 28 and vertically adjustable rollers
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32. Further, the driven rollers 28 and the vertically
adjustable rollers 32 each have an annular groove
corresponding to the shape of the guard material 24
formed in respective radially outer surfaces. Each of
the journals 34 is attached to a jack screw 36 of a
worm gear actuator 38 and driven by a hydraulically
powered rotary actuator 40. The rotary actuators 40
are each supplied by a common source oE pressurized
hydraulic fluid such as a hydraulic pump, not shown,
and convert fluid pressure into rotary power in either
a clockwise or a counterclockwise direction. ~hen
supplied with pressurized fluid from a common manifold,
each of the rotary actuators 40 have an equal output
torque that is transmitted respectively through the
worm gear actuators 38 and the jack screws 36 to the
journals 340 Each of the rollers 32, mounted in the
journals 34, is thus equally urged, depending upon the
preselected power output direction of the rotary
actuators 40, either downwardly into pressure contact
with the guard material 24 positioned between the
respective mating driven roller 28 and the vertically
adjustable roller 32, or upwardly away from such
contact. The magnitude of the pressure contact between
the guard material 24 and the driven rollers 28 is
controlled by the pressure of the hydraulic fluid
equally directed to each of rotary actuators 40.
As shown in Fig. 2, the second means 22 for
feeding a continuous strand of guard material also
preferably includes a tension control device 42 and a
plurality of straightening rollers ~4.
The forming means or head 20 includes a first
portion 46 removably a-ttached in a fixed position to
the frame 26 and a separable second portion 48,
moveably mounted on the frame 16. The second portion
48 is moveable between a first position at which the
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first and second portion 46,48 are spaced apart as
shown in Fig. 10 and a second position, shown in ~ig.
4, at which the first and second portions 46,48 are in
an abutting relationship.
As best shown in Fig. 4, a hydraulic cylinder
50 is attached to the frame 16 and has an extensible
rod end 52 pivotally connected to a first link 54 of a
three member linkage arrangement. The linkage
arrangement also includes a second link 56 pivotally
attached to a vertical member of the frame 16 and a
third linlc 58 pivotally connected to the second portion
48 of the forming head 20. Retraction of the rod end
52 moves the first link 54 to an elevationally lower
position and draws the second portion 48 of the forming
head 20 to the left, as viewed in Fig. 10, to the
position spaced from the fixed first portion 46.
Conversely, extension of the rod end 52 moves the first
link 54 to an elevationally higher position and moves
the second portion 48 to the right into the abutting
position, as shown in Fig. 4, in pressure contact with
the first portion 46.
A plurality of cylindrically-shaped die
members 60, which as shown in Fig. 5, are
alphabetically suffixed with the letters a-h, are
Z5 rotatably mounted in an arcuately spaced relationship
on each of the first and second positions (46,48). In
the preferred embodiment, the die members are desirably
constructed of a carbide steel and, as shown in Fig. 6,
each have a pair of parallel annular grooves 62
circumferentially disposed on a peripheral surface 64
of the die member 60. The grooves 62 are contoured to
mate with the strand of guard material 24 and are
spaced apart a distance "x" equal to the pitch of
adjacent coils of the formed guard member 12.
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As best shown in Fig. 5, the die members
60e,60f, and 60g~ mounted in the first portion 46, and
60d mounted as the second portion 48 of the forming
head 20, are equally radially spaced at a first
predetermined distance "y" from a centrally disposed
longitudinal axis 66. The axis 66 is congruent with
the longitudinal axis of the formed guard member 12 and
is represented in cross section by the point 66 in Fig.
5. The die members 60a, 60b, and 60c, mounted on the
second portion 48, and 60h, mounted on the first
portion 46 of the forming head 20, are radially spaced
from the longitudinal axis 66 at a second predetermined
distance "yl", the second distance ~Iyl~l~ being greater
than the first predetermined distance lly~l~ In the
preferred embodiment, a forming head 20 for forming an
external guard member 12 having an internal diameter of
34.0 mm (1.34 in.) from a strand of spring steel guard
material having a nominal diameter of 3.0 mm (.12 in.),
the groove surface 62 of the die members 60d,60e,60f
and 60g are each equally radially positioned at a
radius llyll of 20.1 mm (.79 in.) from the axis 66, and
die members 60a,60b,60c and 60h are equally radially
positioned at a radius "yl" of 21.6 mm (.85 in.) from
the axis 66.
The eight die members, 60a - 60h, are also
axially spaced along the centrally disposed
longitudinal axis 66. The eight die members 60a - 60h
are each successively axially spaced, inwardly Erom the
plane of the paper, one-eighth of the aforementioned
pitch distance "x". For example, if the desired pitch
distance is 5.5 mm (.22 in.), the die member 60b is
axially spaced one-eighth of the pitch distance or
0.7 mm (.028 in.) from the die member 60a; die member
60c is axially spaced a distance equal to one eighth of
35 the pitch distance or 0.7 mm (.028 in.) from the die
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member 60b; and continuing in clockwise direction each
of the successive die members 60d - 60h are each
progressively spaced a distance equal to one eighth the
pitch distance from the respective preceding die member.
The first and second portions 46,48 of the
forming head 20 also have a plurality of radially
adjustable rollers 68 preferably constructed of a
carbide steel material and disposed in contacting
relationship adjacent each of the die members 60. As
best shown in Figs. 7 and 8, the rollers 68 each have a
pair of radially e~tending parallel flanges 70
circumferentially disposed on a peripheral surface 72
oE the roller 68, and are mounted on the respective
first and second portions 46,48 through an eccentric
adjustable bushing 73. The radial position of each of
the rollers 68, with respect to each ad,acently
disposed die member 60, is controlled by rotation of
the eccentric bushing 73. If desired, a similar
radially adjustable eccentric bushing mounting
arrangement may be used to mount each of the die
members on the respective first and second portions
46,48 of the forming head 20. Such a mounting
arrangement allows wider construction tolerances in the
fabrication of the forming head and provides a means
for readjusting the die members 60 to compensate for
wear during use of the apparatus 10. As an aid to
reducing wear, lubricating oil is supplied to the die
members 60, and more specifically to the surface of the
annular grooves 62, through a pair of oil galleries
74,76 provided respectively in the first and second
portions 46,48. As shown in Fig. 5, the galleries
74,76 communicate a source of pressurized lubricant,
not shown, with a hollow center cavity of each of the
die members 60. The lubricant is directed to each of
the grooved surfaces of the die members 60 by a pair
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radial apertures 78 communicating between the hollow
center cavity and the external surface of the die
members 60.
The third means 26 (FigO 2) for cutting the
strand of guard material 2~ includes an electrical
resistance heated element 80. In the preferred
embodiment, a TIG (tungsten-inert gas) welding head,
used without shielding gas, provides a clean,
rounded-end smooth cut of the spring steel wire guard
material. The element 80 is pivotally mounted on the
frame 16 and is moveable, by a rotary actuator 82,
between a first position at which the element 80 is
spaced from the guard material 24, as shown in Fig. 3,
and a second position at which the element 80 is in
contact with the guard material 24, as shown in Fig.
lO. A clamping member 84 is slideably mounted on the
frame 16 and is moveable by a hydraulic cylinder 86
between a first position at which the clamping member
84 is spaced from the formed guard member 12, and a
second position at which the clamping member 84 is in
pressure contact with the formed guard member 12.
~he first means 18 for supporting at least one
; of the guarci member 12 and the hose 14 includes a
plurality of support stations 88 longitudinally
adjustably spaced on the frame 16, along the axis 66,
as shown in Fig. l. As shown in Figs. l and 9, each of
the support stations 88 has a pair of rotatably mounted
idler rollers 90 and a driven roller 92. Each of the
idler rollers 90 has a hose support surface 94 and a
guard member support surface 96 spaced radially
inwardly of the hose support surface 94. The idler
rollers are mounted on upwardly extending support arms
98 of a laterally adjustable fixture lO0. The support
arms 98 are selectively drawn together or spaced apart
hy rotation of a screw 102 having directionally opposed
t~jJS~z
threads formed at spaced end portions of -the screw
102. Rotation of the screw 102 in a first direction
draws the pair of idler rollers 90 closer together, and
rotation of the screw 102 in a second direction,
opposite the first direction, spaces the rollers 90
away from each other. Each of the driven rollers has a
guard member support surface 104 and a radially
e~tending flange 106 having a width substantially equal
to the space or clearance between adjacent coils of the
formed guard member 12. The flange 106 extends
radially outwardly a distance sufficient for the ~lange
106 to be positi.oned between and frictionally contact
adjacently disposed coils of the guard member 12, but
not sufficient for contacting the hose 14. The idler
rollers 90 therefore support both the hose 14 and the
guard member 12 in a properly spaced radial
relationship, and the driven rollers 92 rotate onl~ the
guard member 12. The driven rollers 92 are driven by a
variable speed motor, not shown, synchronously with the
driven rollers 28 of the second means 22 for feeding a
strand of guard mterial 24 to the forming head 20. In
the preferred embodiment, a vertically and laterally
adjustable roller 108 is disposed above the hose 14 and
~guard member 12 at each of the support stations 88.
:25 The rollers 108 limit the upward movement of the formed
guard member 12 and assure engagement of the guard
member 12 with the drive flange 106 of the driven
rollers 92.
Industrlal Applicabilit~
Forming an external guard member 12 on a hose
14 according to the method of the present invention is
accomplished by first positioning a hose 14, preferably
fully assembled with fittings installed on both ends o~
the hose/ in the forming head 20. The apparatus 10 is
,
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prepared for this first step by moving the first
portion 46 of the forrning head 20 to the first, or open
position and moving the adjustable rollers 108 on the
suppor~ stations 88 la-terally to a position spaced from
vertical alignmen-t midway between the pairs of idler
rollers 90. With the apparatus 10 thus prepared, the
assembled hose 14 is easily positioned in the apparatus
10 by vertically lowering the hose 14 until i.t is at
rest on the idler rollers 90. The hose 14 is axially
aligned, along the axis 66 by positioning one end of
the hose 14 immediately to the right of the forming
head 20, as shown in Fig. 1.
The second portion 48 of the forming head 20
is moved to the second, or closed, position in abutting
contact with the first portion 46 by pressurizing
hydraulic cylinder 50. After movement to the second
position, the second portion 48 is maintained in
contact with the first portion 46 by maintaining a flow
o~ pressurized fluid to the hydraulic cylinder 50.
A continuous strand of guard material 24, such
as round, hard drawn spring wire of SAE 1060 steel and
having a nominal diameter of 3.0 mm (.12 in.) is fed
from a supply reel, not shown, through the tension
control device 42, the straightening rollers 44, and
the second means 22 to the forming head 20. The strand
of guard material 24 is maintained in pressure contact
with the plurality of driven rollers 28 of the second
means 22 by d.irecting a flow of equally pressurized
h~draulic fluid from a cornmon source to preselected
ports of the rotary actuators 40. The rotary actuators
40 each provide an output torque of equal magnitude to
the respective worm gear actuators 38 and hence to the
jack screws 36 connected to the vertically adjustable
journals 34 of the rollers 32. Accordingly, the
rollers 32 are each equally urged downwardly against
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the strand of guard material 24, urging the guard
material 24 into pressure contact with the driven
rollers 28. The variable speed motor 24 synchronously
drives each of the driven rollers 28 and the strand of
guard material 2~ is continuously and forcibly directed
into the forming head 20~
After entry into the forming head 20, the
strand of guard material 2~ is guided to the second
portion 48 of the forming head by a first of the pair
of annular grooves 62 formed in the die members 60h and
60a. Initially, to start the actual coil formation, an
end of the strand 24 is manually raised and positioned
in contact with the first groove 62 in the die member
60b. The drive rollers are then actuated to continue
driving the strand of guard material 24 into the
forming head 20, and the end of the strand pro-
gressively contacts the first groove of die members
60c,60d,60e,60f,60g forming a first complete coil, and
then continuing on, passes radially inwardly of the
20 second groove 62 of the die members 60h,~0a,60b, and
60c and progressively contacts the second groove 62 of
die members 60d,60e,60f, and 60g forming a second
complete co:il of the guard member 12 before exiting the
forming head 20. Since the die members 60b and ~Oc are
radially spaced at a distance "yl", greater than the
radial distance "y" at which the remaining die members
are positioned, the strand of guard material 24 is
initially urged into a first coil shape having a first
predetermined diameter as represented by the section of
the first formed coil of guard material 24 extending
from die member 60a to die member 60c in Fig. 5. The
strand of guard material is thus initially uryed into a
smaller diameter coil shape than desired for the final
coil diameter.
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It has been found that overbending, or
initially urging the guard material into the smaller
than final diameter, is highly desirable in forming
guard members of spring steel wire material. Further,
by forming two complete coils of the guard member 12 in
the forming head 20, in conjunction with the initial
overbending, virtually eliminates any tendency for the
formed coils to "spring back" and assume a larger than
desired diameter after exiting from the forming head
20. It has been this tendency, and the problems
associated with forming spring steel wire which have
heretofore prohibited the in situ forming of a spring
steel wire guard member about a soft mandrel, or as in
the preferred embodiment of the present invention, a
preassembled hydraulic hose.
It is common practice to precoat guard
material, such as spring steel wire, to protect the
material during storage and shipping. The coating
material and other accumulated matter, however, have a
tendency to rub off and build up on the die members 60
during formation of the coil shapes. The flanges 70 of
the radially adjustable rollers 58 are each positioned,
prior to use of the apparatus 10, in light contact with
the respective annular grooves 62 of adjacently
positioned die members 60. The light contact between
the carbide steel rollers 68 and carbide steel die
members 60 ser~es to remove extraneous material from
the forming surEaces of the die members 60, maintain
the forming surface in a clean condition, and prolong
the useful life of the die members 60. As the rollers
68 and die members 60 wear, they may be easily
repositioned by rotation of the respective eccentric
mounting bushing 73.
After exiting the forming head 20, the formed
guard rnaterial continues to rotate about the hose 14
and advances axially towards the end oE the hose
opposite the forming head 20. The rotation and
advancement o~ the guard member 20 is aided by
frictional engagement of the driven rollers 92 between
adjacently formed coils of the guard member 12~
Upon completion of the formation of the guard
member 12, hydraulic pressure to the cylinder 50 is
redirected, and the rod end 52 is retracted, returning
the second portion 48 of forming head 20 to the first,
or open, position at which the second portion 48 is
spaced from the first portion 46. Simultaneously with
retraction of the second portion 48, the cylinder 86 is
pressurized and the clamping member 84 is urged into
pressure contact with the formed guard member 12, as
shown in Fig. 10. With the guard member 12 thus
restrained in a fixed position with respect to the
first portion 46 of the forming head 20, the resistance
heated element 80 is rotated into contact with the
first partially-formed coil of the guard material 24
and supplied with electrical current. The coil~ at the
point of contact with the element 80, is quickly heated
to the melting temperature of the guard material 24 and
the motor 29 is activated to urge the partially formed
portion o~ the guard material 24 away from the formed
guard member 12.
After cutting the strand of guard material 12,
the adjustable rollers 108 are moved laterally and the
hose 14, with the complete external guard member 12
formed thereabout is vertically removed from the
support stations 88 and the forming head 20.
Other aspects, ob~ects and advantages of this
invention can be obtained from a study of the drawings,
the disclosure and the appended claims.
