U.S. patent number 3,836,122 [Application Number 05/308,165] was granted by the patent office on 1974-09-17 for cable winch.
Invention is credited to Wayne M. Pierce, Jr..
United States Patent |
3,836,122 |
Pierce, Jr. |
September 17, 1974 |
CABLE WINCH
Abstract
A three-speed hydraulic winch includes a base, a drum support, a
drum shaft mounted on the support, a cable drum rotatable on the
drum shaft and means mounting the support on the base for
reciprocation substantially parallel to the drum shaft. A cable
guide pulley is rotatably mounted in a pulley block which is
fixedly mounted on the base. An endless chain traverse means is
coupled between the base and the support to reciprocate the
support. Four hydraulic motors constitute the drive means, and are
operable to rotate a gear having clutch teeth on one face
engageable with clutch teeth on a flange of the drum, and a chain
and sprocket drive interconnects the drum and the endless chain
traverse means. The guide pulley is operatively associated with an
angle sensing device controlling the pull of the winch and
controlling the load on the drum to a constant predetermined
maximum. When the clutch is disengaged and the drum is free to
rotate, a disk brake is automatically engaged if there is no
tension on the cable, to prevent cable over-ride and hang-up, and
this brake is released responsive to cable tension. The clutch
cannot be disengaged if the cable is under tension. An extension
shaft may be provided for driving a capstan or any other device.
The fixed positioning of the cable guide pulley on the base,
combined with a traversing movement of the drum, provides for level
winding without the cable sweeping across the support during
winding on the drum or unwinding therefrom. The pull on the cable
is always in line with the guide pulley and there is "no side
pull," thus maintaining the load at a minimum.
Inventors: |
Pierce, Jr.; Wayne M. (Milford,
CT) |
Family
ID: |
23192835 |
Appl.
No.: |
05/308,165 |
Filed: |
November 20, 1972 |
Current U.S.
Class: |
254/273; 254/295;
254/340; 254/361; 254/331; 254/347 |
Current CPC
Class: |
B66D
1/14 (20130101); B66D 1/28 (20130101); B66D
2700/0183 (20130101) |
Current International
Class: |
B66D
1/02 (20060101); B66D 1/14 (20060101); B66D
1/28 (20060101); B66d 001/48 () |
Field of
Search: |
;254/172,173R,175.7,175.5,175,174 ;242/37,158R,158.1,158B |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Schacher; Richard A.
Attorney, Agent or Firm: March, Esq.; Arthur A.
Claims
What is claimed is:
1. A cable winch comprising, in combination, a base; a drum
support; a drum shaft mounted on said support; a cable drum
rotatable on said drum shaft; means mounting said support on said
base for reciprocation substantially parallel to said drum shaft; a
cable guide pulley; a pulley block rotatably mounting said pulley
and fixedly mounted on said base; drive means selectively operable
to rotate said drum to feed cable to and from said drum over said
guide pulley; traverse means coupled to said support and to said
base and operable to reciprocate said support relative to said base
parallel to said drum shaft to effect level winding and unwinding
of cable during rotation of said drum; driving mechanism
interconnecting said drum and said traverse means; a capstan shaft
rotatably mounted on said drum support in spaced parallel relation
to said drum shaft and extending outwardly through a side wall of
said base; the projecting end of said capstan shaft being designed
for engagement by an operating tool to rotate said capstan shaft; a
normally engaged clutch interposed between said drive means and
said drum and including a clutch drive gear; and gearing
continuously interconnecting said gear and said capstan shaft for
rotation of said capstan shaft whenever said gear is rotated.
2. A cable winch, as claimed in claim 1, in which said drive means
comprises hydraulic motor means driving one element of said clutch;
and a pilot valve controlling supply of hydraulic fluid to said
hydraulic motor means; said rocker including a cam cooperable with
said pilot valve and operable, responsive to slack in the cable, to
close said hydraulic valve to prevent supply of hydraulic fluid to
said hydraulic motor means to arrest rotation of said drum.
3. A cable winch comprising, in combination, a base; a drum
support; a drum shaft mounted on said support; a cable drum
rotatable on said drum shaft; means mounting said support on said
base for reciprocation substantially parallel to said drum shaft; a
cable guide pulley; a pulley block rotatably mounting said pulley
and fixedly mounted on said base; drive means selectively operable
to rotate said drum to feed cable to and from said drum over said
guide pulley; traverse means coupled to said support and to said
base and operable to reciprocate said support relative to said base
parallel to said drum shaft to effect level winding and unwinding
of cable during rotation of said drum; driving mechanism
interconnecting said drum and said traverse means; a normally
engaged clutch interposed between said drive means and said drum;
said drive means comprising hydraulic motor means driving one
element of said clutch; and cable tension sensing means operatively
associated with said cable guide pulley; said tension sensing means
comprising a shaft rotatably supporting said guide pulley; a
pendulous rocker oscillatably mounted on said pulley shaft; a pair
of further pulleys rotatably mounted on said rocker and having the
cable, trained over said guide pulley, passing over said further
pulleys; a disk brake normally engaged with said drum to prevent
rotation thereof; and a normally closed switch effecting engagement
of said disk brake with said drum; said rocker, responsive to
tension in said cable, engaging an operator of said normally closed
switch to open said switch and, responsive to slack in the cable,
disengaging said switch operator to effect closing of said normally
closed switch.
4. A cable winch comprising, in combination, a drum support; a drum
shaft mounted on said support; a cable drum rotatable on said drum
shaft; hydraulic motor means in driving connection with said drum;
cable tension sensing means operatively associated with the cable;
a pilot valve included in said tension sensing means and
controlling supply of hydraulic fluid to said hydraulic motor means
and operable, responsive to slack in the cable, to prevent supply
of hydraulic fluid to said hydraulic motor means and operable,
responsive to slack in the cable, to prevent supply of hydraulic
fluid to said hydraulic motor means to arrest rotation of said
drum; said hydraulic motor means comprising:
four hydraulic motors operable to rotate said drum;
electromagnetically operated valve means selectively operable to
connect said motors in parallel to a source of hydraulic fluid
under pressure, for low speed high torque operation of said winch,
to connect said motors in series to said source for high speed low
torque operation of said winch, and to connect said motors in
series-parallel to said source for intermediate speed operation of
said winch; and
speed selector switch means connected in controlling relation with
said electromagnetically operated valves.
Description
FIELD OF THE INVENTION
This invention relates to cable winches and, more particularly, to
a novel and improved hydraulically driven cable winch which is free
of disadvantageous features of prior art cable winches.
BACKGROUND OF THE INVENTION
Cable winches are used for many purposes, including hoisting
operations and the drawing of underground cable through trenches,
conduits and the like. Known cable winches, particularly those for
drawing underground electrical cable, have some disadvantages and
operational hang-ups. Among these may be mentioned the dragging of
the cable across the winch platform by a traversing mechanism which
is used to effect level winding and unwinding of cable during
rotation of a cable drum. This action places an undesirable load on
the level winding mechanism. Another disadvantage is the inability
of known cable winches to maintain a constant loading on the
cable.
When a cable is payed out under power, difficulty is experienced in
preventing a wire rope or cable from "piling up" and from
performing loose wrapping or unwrapping relative to the drum.
Additionally, known winches are not easily removable and accessible
as a unit for maintenance, inspection and repair.
SUMMARY OF THE INVENTION
This invention relates to cable winches and, more particularly, to
a novel and improved hydraulic driven winch particularly designed
for the drawing of underground electric cable and free of the
disadvantages of known prior art winches used for this purpose.
In accordance with the invention, a cable drum support is mounted
on a base in a manner to provide for reciprocation laterally of the
base and substantially parallel to the rotating axis of the drum. A
cable guide pulley is rotatably mounted in a pulley block which is
fixedly mounted on the base, and traverse means are coupled to the
drum support and to the base to reciprocate the support relative to
the base to effect level winding and unwinding of cable during
rotation of the drum aand without the cable being dragged sideways
or laterally across the base.
The driving means for the cable drum comprises, preferably, four
hydraulic motors which may be connected in parallel, for high
torque and low speed operation, in series, for low torque and high
speed operation, or in parallel-series for an intermediate range. A
valve-operated shifting system eliminates mechanical levers and
gear boxes, with the gears being constantly in mesh to eliminate
problems due to engaging, noise and gear wear, and permitting
shifting without slipping.
This is substantial advantage over the prior art winches which rely
upon mechanical shifting requiring a complete stop of the winch
before shifting. Shifting with the winch of the invention can be
remotely controlled in a simple manner whereas, in the prior art,
remote control is either lacking or else requires expensive and
cumbersome equipment, whether the winch is hydraulically or
mechanically operated.
The cable guide pulley includes an angle sensing device which
controls the pull of the winch, and maintains constant load on the
winch at all times. Driving of the drum is effected by a gear
driven by the drive means, and having clutch teeth on one face
thereof engageable with clutch teeth on a face of the drum. When
the clutch is disengaged and the drum is in a free wheeling
condition, a disk brake is automatically engaged with a drum flange
if there is no tension on the cable, thus preventing cable
over-ride and hang-up. This brake is released when tension is
applied to the cable.
A clutch interlock is provided in such a manner that the clutch
cannot be disengaged if the cable is under tension, and also
requires tension on the cable for paying out under power. This
prevents "pile up" of the cable and loose wrapping.
Optionally, an extension shaft, which continuously rotates with the
winch may be provided whereby a capstan or any other device may be
driven.
An object of the invention is to provide an improved cable winch
particularly designed for the laying of underground electrical
cable.
Another object of the invention is to provide such a winch which is
free of the disadvantages of known prior art winches used for this
purpose.
A further object of the invention is to provide such a cable winch
in which the cable drum is reciprocated parallel to its axis to
provide for level winding and unwinding of the cable during
rotation of the drum and without a cable being drawn laterally
across the drum support base and thus adding a heavy load to the
level winding mechanism.
Another object of the invention is to provide such a cable winch
which is removable as a unit from its support base for ready
inspection, maintenance and repair.
A further object of the invention is to provide such a cable winch
in which cable over-ride and hang-up is automatically
prevented.
Another object is to provide a valve-operated shifting system
providing for shifting without slipping.
Another object is to provide for such a winch which can be shifted
"on the fly".
A further object of the invention is to provide such a cable winch
in which cable "pile up" and loose wrapping are automatically
prevented.
For an understanding of the principles of the invention, reference
is made to the following description of a typical embodiment
thereof as illustrated in the accompanying drawing.
BRIEF DESCRIPTION OF THE DRAWING
In the drawing:
FIG. 1 is a perspective view of a cable winch embodying the
invention;
FIG. 2 is a back elevation view of the winch, corresponding to FIG.
1;
FIG. 3 is a side elevation view taken on the line 3--3 of FIG.
2;
FIG. 4 is a sectional view taken on the line 4--4 of FIG. 3;
FIG. 5 is a sectional view taken on tthe line 5--5 of FIG. 3;
FIG. 6 is a view taken on the line 6--6 of FIG. 1;
FIG. 7 is a view taken on the line 7--7 of FIG. 6;
FIG. 8 is a view taken on the line 8--8 of FIG. 1; and
FIG. 9 is a schematic wiring diagram of the interlock and control
system of the winch.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 2, a winch embodying the invention is
illustrated as comprising a base 10 carrying a drum support 15
having a drum shaft 25 rotatably mounting a cable drum 20. Base 10
is a generally rectangular structure including a bottom wall 11,
side walls 12, a front strut 13 extending between side walls 12 and
a traverse support rod 14 extending between side walls 12
rearwardly of strut 13. In a manner to be described, strut 13 and
rod 14 support drum support 15 for lateral reciprocation or
traverse relative to base 10. Cable C, wound on drum 20 or unwound
therefrom, passes through a cable guide 30 which is fixedly secured
to strut 13, preferably at its midpoint. The hydraulic drive and
control unit 50 for the winch is mounted at the rear end of base 10
and includes a high capacity hydraulic fluid reservoir 51 provided
with a filter 52.
Drum support 15 comprises a front wall 16 interconnecting a pair of
side walls 17, 17. In inwardly spaced and parallel relation to each
side wall 17, there is a respective inner side wall 17', and each
pair of outer and inner side walls 17, 17', near its rear end, has
secured thereto a respective trunnion 18 slidably engaging the
tubular traverse shaft 14. Adjacent front wall 16, relatively
narrow partitions 16' extend between each outer side wall 17 and
the adjacent inner side wall 17' and, partition 16', in cooperation
with front wall 16, rotatably mounts respective rollers 19 which
ride on a track formed by front strut 13. Trunnions 18 and rollers
19 serve to support drum support 15 for reciprocation laterally of
base 10 and parallel to the axis of rotation of drum 20. The
traverse mechanism 40, for effecting such reciprocation or
traverse, will be described in detail hereinafter.
A pair of tubular cross members 21 extend between each outer side
wall 17 and its adjacent inner side wall 17', tubular cross members
21 being welded at opposite ends to the associated side walls. Each
rear tubular member 21 is located at a substantially higher level
than the associated front tubular member 21. Each tubular 21 has
welded or otherwise secured thereto the outer end of an associated
strut 22, and the inner ends of struts 22 are welded or otherwise
secured to bearings 23 for drum shaft 25 rotatably mounting drum
20. Drum shaft 25 preferably is tubular.
Drum 20 comprises a pair of annular flanges 26, 26' whose inner
peripheries are secured to respective bearings 27 engaged with
shaft 25. A drum cylinder 28 extends between flanges 26 and 26' and
is welded or otherwise secured thereto at its opposite ends,
cylinder 28 having internal annular ribs 24, the outer ends of
which are secured to bearings 27. The construction of drum 20 is
best illustrated in FIG. 4.
Referring to FIGS. 1, 2, 3 and 4, a gear 35, having a diameter
somewhat greater than the diameter of flange 26, is rotatably
mounted on drum shaft 25 adjacent the outer surface of flange 26'.
Through the medium of a key 36 extending through relatively
elongated diametrically opposite slots 37 in tubular shaft 25, and
engaged in a channel-shaped recess in the inner surface of the hub
37 of gear 35, gear 35 is displaceable axially relative to flange
26'. As best seen in FIG. 8, the outer surface of flange 26' has
welded thereto radially inwardly directed clutch teeth 29 which are
arranged to mesh with radially outwardly directed clutch teeth 38
on the inner lateral surface of gear 35. Thus, the flange 26' and
the gear 35 cooperate to form a disengageable clutch, which is
controlled electromagnetically as will be described hereinafter.
Gear 35 meshes with the output or drive shaft 61 one motor of the
four rotary hydraulic motors 60, mentioned above, and which are
disposed in circumferentially spaced relation around the lower
portion of gear 35 and are mounted in one set of side plates 17,
17' of drum support 15. While each of the motors can be mounted in
any one of four positions, only one motor 60 is shown, in FIG. 2 of
the drawing. Gear 15 also constantly meshes with an idler pinion 62
which is in constant mesh with a pinion 56 secured on a shaft 55
rotatably mounted in bearings 57 secured to each outer side wall
17. At its right end, as viewed in FIG. 1, shaft 55 extends
outwardly from one of the motors with clearance, slidably through a
protecting sleeve 58 on the right side wall 12 of base 10, and its
outer end is formed for coupling. It will be noted that capstan
shaft 55 is continuously rotated whenever gear 35 is driven.
Extension shaft 55 is slidably mounted for displacement with the
winch, and can drive a capstan or any other device.
As best seen in FIGS. 1, 2, 3 and 4, flange 23 has secured thereto,
in axially spaced relation, a chain sprocket 41 and a braking disk
46. Disk 46 is engageable by a disk brake 45, whose operation is
described more fully hereinafter. An endless chain 42 is trained
about sprocket 41 and about the input sprocket 43 of a gear box 44
mounted on the adjacent side wall 17 of drum support 15.
As best seen in FIGS. 2, 3 and 5, gear box 44 has a downwardly
extending vertical output shaft 47 to the lower end of which are
fixed two sprockets 48, 48 rotatably mounted in one part 53A of a
two-part adjustable length support carried by a member 54 secured
to the undersurface of drum support 15. A second pair of axially
spaced sprockets 58, 58 are mounted on the outer end of the other
part 53B of the adjustable length support, and endless chains 49
connect sprockets 48 to sprockets 58. A block 63 is secured to the
endless chains 49 and has a pin 65 extending downwardly therefrom
and engaged in an elongated slot 66 in a block 64 secured to the
bottom wall 11 of base 10. Slot 66 is elongated in a direction
perpendicular to the axis of rotation of drum 20, and allows block
63 with pin 65 to move around the sprockets 48 and 58. With the
described construction of the traverse mechanism 40, as drum 20 is
rotated, chains 49 are driven and pin 65 is reciprocated laterally
of drum support 15. However, as pin 65 is fixed against lateral
movement with respect to bottom wall 11 of base 10, the travel of
pin 65 causes drum support 15 to be reciprocated parallel to the
axis of rotation of drum 20, thus effecting even winding of cable C
on drum 20 and even unwinding of cable C from the drum.
It is this arrangement which permits the use of the fixed cable
guide 30 which, as stated, is mounted in a fixed position on strut
and of base 10. As best seen in FIGS. 6 an 7, cable guide 30
includes a support 31 fixed to strut 13 and rotatably mounting a
cable sheave or pulley 32 under which cable C passes to and from
drum 20. Pulley 32 is rotatably mounted on a shaft 33 which
oscillatably supports a pendulous rocker 34 forming part of a cable
tension sensing mechanism generally indicated at 70. The tension
sensing mechanism includes a relatively large diameter pulley 71,
rotatably mounted on rocker 34, and a relatively small diameter
pulley 72 rotatably mounted in an arm 73 rockable about the axis of
rotation of pulley 71. Cable C, in passing from sheave 32 to drum
20, engages the pulleys or sheaves 71 and 72. Arm 73 has a portion
engageable with the operator 74 of a normally closed switch 75
controlling application of disk brake 45 to brake disk 46. When
cable C is under tension, arm 73 moves clockwise to open switch 75
through operator 74. However, when the cable becomes slack, arm 73
swings downwardly counterclockwise to release operator 74 so that
switch 75 closes to apply disk brake 45 to brake disk 46.
Rocker 34, which comprises two parallel arms or plates, carries a
cam portion 76 engageable with the operator 77 of a pilot valve 78
mounted on fixed support 31. The tension sensing mechanism sets the
maximum load through displacement of cam portion 76. Such movement
results from the fact that pulley 72 is not in a straight line
between pulleys 32 and 71, so that it is displaced in accordance
with the cable tension, resulting in angular displacement of rocker
34 and movement of cam portion 76 to operate pilot valve 78.
Pilot valve 78 controls the operation of the motors 60 in such a
manner that, unless cable C is under tension, as sensed by the
tension sensing pulley 72, cable drum 20 cannot be power driven, or
will not "power out", when paying out cable C. This prevents
kinking and flopping of the cable which might occur if drum 20 were
power driven in a cable unwinding direction without there being
tension on the cable.
All functions of the winch, including operation of the clutch
formed by gear 35 and flange 26' of drum 20, are controlled by
remotely located electric switches. This remote control allows the
operator to stand away from the winch and nearer the work area, for
convenience and safety. The interlock control system is
schematically illustrated in FIG. 9.
Referring to FIG. 9, the aforementioned clutch is indicated at 80,
and is normally engaged but may be disengaged upon energization of
its operating winding. Disk brake 45 also has an operating winding.
Both brake 45 and clutch 80 are under the control of the tension
sensing switch 75 which has an operator 75A which normally closes
an upper pair of contacts. However, when tension is applied to
cable C, operator 75A engages the lower pair of contacts. The
supply of hydraulic fluid to the four motors 60 is either
established or blocked by pilot valve 78. If cable C is under
tension, switch 75 is opened to disconnect the clutch valve, and
pilot valve 78 is open so that hydraulic fluid can be supplied to
the motors in accordance with the setting of the controls. However,
if cable C is slack, pilot valve 78 is closed, preventing supply of
hydraulic fluid to the motors. All controls are electrically
motivated.
The control current is supplied from a grounded source of
potential, whose ungrounded terminal is indicated at 86. Terminal
86 is connected, through a safety switch 87, to the movable arm 85A
of a main switch 85 which ccontrols the supply of power to the
motor 60 as well as the direction of rotation thereof. In the
illustrated position of arm 85A, the motors are deenergized. If arm
85A is moved to engage contact 85B, the motors are operated in a
direction to rotate drum 20 clockwise to draw in cable C and wind
it on the drum and, if arm 85A is moved to engage contact 85C, drum
20, provided the cable C is under tension, is rotated
counterclockwise to pay out cable C. For this purpose, contact 85B
iis connected directly to one operating winding 81A of a reversing
valve 81. The other contact 85C is connected to one of the lower
contacts of switch 75 and, if operator 75A is engaged with the two
lower contacts, contact 85C of switch 85 is connected to the other
operating winding 81B of reversing valve 81.
As previously mentioned, all four motors 60 may be connected in
parallel to the source of hydraulic fluid under pressure for high
torque and low speed operation of the winch. They also may be
connected in series to the source for low torque high speed
operation of the winch. For an intermediate speed range, the four
motors are connected in series-parallel with each other. That is,
the motors are connected in pairs in parallel to the source of
hydraulic fluid under pressure, with each pair of motors including
two motors connected in series with each other. The various
connections are established by the valves 82, 83 and 84 which are
electromagnetically operated and are under the control of a speed
selector switch 90. For high speed operation, all three valves 82,
83 and 84 are closed. For the intermediate speed range, switch 90
is operated to open valves 83 and 84 which establish the
series-parallel connection of the motors. For a low speed
operation, all three valves 82, 83 and 84 are opened, under the
control of switch 90, so that all the motors 60 are connected in
parallel to the source of hydraulic fluid under pressure.
A relay 78 has its energizing winding connected in parallel with
the energizing winding of clutch 80 so that, when clutch 80 is
disengaged by energization of its electromagnetic winding, horn
relay 78 is energized. For free spooling of the drum, a free spool
switch 91, which is a single pole double throw switch, is connected
in series between safety switch 87 and the upper contacts of switch
75. With the described connections, when clutch 80 is disengaged
and the winch is in a free spool condition, disk brake 45 is
automatically engaged if there is no tension on cable C, thus
preventing cable override and hang-up. Brake 45 is released when
there is tension on cable C. The interlock is so designed that
clutch 80 cannot be disengaged if the cable C is under tension,
aand also to require tension in cable C for paying out under power.
This prevents cable "pile-up" and loose wraps of the cable.
While a specific embodiment of the invention has been shown and
described in detail to illustrate the application of the principles
of the invention, it will be understood that the invention may be
embodied otherwise withouut departing from such principles.
* * * * *