US2320554A

US2320554A - Hydraulic spooling device

Info

Publication number: US2320554A
Application number: US428155A
Authority: US
Inventors: Edward R Barrett
Original assignee: Gar Wood Industries Inc
Current assignee: Gar Wood Industries Inc
Priority date: 1942-01-26
Filing date: 1942-01-26
Publication date: 1943-06-01
Anticipated expiration: 1960-06-01

Description

Lv BARRETT HYDRAULIC SPOQLING DEVICE June 1, 1943.

June 1, 1943,a E. R. BARRETT 2,320,554

HYDRAULIC SPOOLING DEVICE Filed Jan. 26, 1942 s sheets-sheet 2 June 1943. E. R, BARRETT HYDRAULIC SPOOLING DEVICE Filed Jan. 26, 1942 3 Sheets-Sheet 3 .MHHI

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IN VEN TOR Zyl/Vari ,Br/gif ATTORNEYS- Patented June 1, 1943 UNITED STATES PATENT OFFICE HYDRAULIC SPOOLING DEVICE Application January 26, 1942, Serial No. 428,155

14 Claims.

The present invention relates to improvements in hydraulic actuating devices, and particularly to such devices employed in the spooling of cable, or the like. l

One of the primary objects of the present lnvention is to provide simplified hydraulic actuating devices which are economical to construct and install.

Another object of the invention is to provide improved devices of the type mentioned which are positive in their action.

Another object of the invention is to provide improvements in hydraulically actuating spooling devices, or level winders, for guiding a cable as it is wound on a spool, or drum, of a power driven winch in synchronism with the speed of such spool, or drum.

Another object of the invention is to provide improvements in devices of the type mentioned so that such devices are compact and occupy relatively little room on the Winches on which they are employed.

Another object of the invention is to provide improvements in spooling devices for power driven Winches which are positive in their action even when there is a relatively heavy line pull on the cable.

Other objects of the invention will become apparent from .the following specification, the drawings relating thereto, and from the claims hereinafter set forth.

In the drawings, in which like numerals are used to designate like parts in the several views throughout:

Figure 1 is a top plan view of a power driven winch having a spooling device, or level Winder, according to the present invention associated therewith;

Fig. 2 is an enlarged, fragmentary cross-sectional view taken substantially along the line 2-2 of Figure 1;

Fig. 3 is a cross-sectional view taken substantially along the line 3-3 of Figure 2;

Fig. 4 is an enlarged cross-sectional View taken substantially along the line 4-4 of Figure 2;

Fig. 5 is a cross-sectional view taken substantially along the line 5-5 of Figure 3;

Fig. 6 is a cross-sectional view taken substantially along the line 6 5 of Figure 4;

Fig. 7 is an enlarged cross-sectional view taken substantially along the line 1-1 of Figure 2;

Fig. 8 is' a view similar .to Figure 2, and showing a modified form of the present invention; and

Fig. 9 is a fragmentary view similar to Figure 2, and illustrating another modified form of the present invention.

Referring to the drawings, and referring particularly to Figures 1 through 'l thereof, in which one embodiment of the present invention is illustrated, a power winch is generally indicated at l0 comprising a standard i2, having a spool or drum i4 keyed to shaft I6 for rotation therewith. The ends of such shaft i6 are disposed in suitable bearings on the standard l2.

Such shaft I6 is driven to drive .the spool I4 through suitable means, such as a. suitable motor i8 which is operatively connected through a gear reduction mechanism 20 with a driving sprocket 22. Such sprocket 22 is connected to another sprocket 2d, which is keyed to the shaft i6, through a chain 26.

A cable 28 is adapted to be wound onto the spool i4 or unwound therefrom, and level Winder or spooling means generally indicated at 30 are provided for guiding the cable 28 as it traverses the space between the ends of the spool I4.

It is pointed out that the term cable as here used and as used in the claims is intended to be generic, and includes stranded cable, single wire. rope, and vthe like.

The level Winder 3l! is mounted upon a pair of standards 32 disposed adjacent the standards I2 and in such a position that the guide for the cable 28 reciprocates in a path substantially parallel to 'the axis of the shaft I6 and between the ends of the spool I4. A casing 34 is fixedly connected to one of the -standards 32 and includes a central bore 36. A piston or plunger 38 is disposed within the bore 36 in engagement with the wall thereof, and is adapted to rotate and reciprocate therein.

In order to effect such rotation and reciprocation of the piston 38 within the bore 36 of the casing 34, such piston 38 is formed with an axial recess 40 in one end thereof which is adapted to slidably receive therein a drive shaft 42. The plunger 38 and the drive shaft 42 are formed with axially extending, complementary grooves or recesses 44 and 46, respectively. preferably at diametrically opposed points, which are adapted to receive therein balls 48. Such balls provide the rotative driving connection between the drive 42 and the piston 38, and permit relative axial movement therebetween.

The drive member 42 has a reduced end portion 50 which extends through a sealed opening 52 formed in the outer end of the casing 34, to the outer end of which is keyed a sprocket wheel 54. The reduced end of the member 42 is also to another sprocket wheel 88A through a chain 88.

Such sprocket wheel 88' is keyed to the end of the shaft I8. so that the member 42 is synchronously driven with the spool I4.

The axial movement of the piston 88 is effected by means of a continuous cam groove 88, which is now accelerating to obtain uniform movement, formed in the peripheral surface thereof, which is disposed at a predetermined angle with respect to the axis of the piston 88 and the axis of the shaft 42, in order to effect the desired axial displacement of the piston 38 rupon rotation thereof. I'his axial movement' is effected by means of a pin 88 which is threadably received through a boss in the casing 84 and projects inwardly of the wall 82. Such pin 88 projects radially inwardly into engagement with the side walls of the groove 88, so that as the piston 38 is rotated, the engagement of the inner end of the pin B8 with the cam groove 58 will cause the piston 88 to reciprocate within the bore 88. The member 88 is shown as a pin, but it will be understood that the inwardly projecting end of such member could be constructed with a rotatable bearing ring or ball, if desired.

The piston 88 is constructed with an end wall G4 having an axial opening therethrough, and the opposite end of such piston is provided with axially extending spaces 88 communicating with the axial opening. The space within the bore 36 is adapted to receive therein separate supplies of fluid, such as oil, on opposite sides of the wall 84 of the piston, as indicated at 68 and 18. 'I'he fluid supply 18 fills the space within the bore behind the piston wall 84 within the spaces 66.

Annular seals 12 are provided in the periphery of the piston 38 to prevent leakage of fluid from one of the supplies 18 to the other along the periphery of the piston.

Separate or communicating fiuid reservoirs, of small capacity, are provided for merely insuring a full supply of iiuid to each Aof the Isupplies 88 and 18 on opposite sides of the piston, and such reservoirs are in the form of separate annular chambers 14 and 18 formed in the casingr 34. Filling openings having removable plugs therein are provided in the top of the cylinder 34 communicating with each of the chambers 14 and 16, if they are separated, or a single opening may be used if they communicate.

Communication between chamber 14 and the supply 88, on one side of the piston 88, is through a passageway 18, disposed adjacent the bottom of chamber 14, having a resilient check valve assembly 88 disposed therein 'so that the fluid from the chamber 14 only enters the supply 88 in the event of a loss of fluid therein, and such fluid cannot pass from the supply 88 back into the chamber 14.

A suitable opening A82 having a removable plug 84 therein is provided through the 'casing 84 in alignment with the check valve assembly 88, so that such check valve may be readily installed.

A similar passageway and check valve indicated by the same number 88, as shown in Figure 3, is provided for communicationbetween the chambers 18 and the fluid supply 18 at the tions of the partitioning member opposite side of the piston 88 -for permitting s supply of fluid to enter the supply region v18. lbut preventing the return of fluid therefrom back to the chamber 18. I

Thus, a full supply of fluid is insured on both sides of the piston 12, but the fluid cannot return from either of such sides to the reservoirs.

In order to guide the cable 28 as it is wound upon the spool I4 or unwound therefrom, a linearly movableor reciprocable element 88is dis- POsed between and mounted on the `standards 82. Such member 88 is in the form of a tubular casing having radially inward, annular flanges formed on the ends thereof with 'annular sealing means 88 fixed to the faces thereof.

Such member 88 is adapted to be slidably mounted upon another tubular member 88. which is fixed to the standards 82 and is in axial align-I ment with the bore 88 and in communication with such bore. A separating ring portion 82 is interposed in the member 88 substantially midway between the ends thereof and provides a partition separating such member 88 into chambers 84 and 88. The annular surface of the member 82 slidably engages the inner surface of the member 88 and is provided with annular sealing means 88 in order to prevent leakage therealong.

The member 88 is of slightly greater diameter than the member 88, so that annular spaces arc provided therebetween. Such annular spaces are indicated at |8| and |82 on oppomte sides of the partitioning member 82, and, in effect, form expansible and contractlble chambers having annular end wall portions |84 and |88, respectively. The opposite ends of each of the annular chambers are defined by the annular portions |88 and III, respectively.which are those por- 82 which project within the space between the members 88 and 88.

The chamber 84 is in open communication with the chamber |8| through a plurality of apertures ||2 formed in the member 88; and the chamber 88 is in opencommunication with the chamber |82 through a plurality of similar apertures ||4 formed in the member 88 on the op posite side of the partitioning member 82.

An axially extending tubular member ||8 is fixed to the wall 88 of the piston 88, and projects into the member 88 with a space between the walls thereof. The end of such tubular member |88 is slidably received within a sealed axial opening III formed in the partitioning member 82, so

. that the open end of the member ||8 projects within the chamber 88. 'Ihe opposite open end of the conduit I|8 communicates with the supply 18 within the casing 84 through the axial opening or passageway 88 formed in the piston 88.

The chamber 84 communicates with the supply 88 throughvthe opening inthe casing 84 and through the space between the outer periphery of the member ||8 and the opening in member 88 adjacent the casing 84.

The member 88 has a housing |28 formed integral therewith, or suitably fixed thereto. substantially midway between the ends thereof. which is adapted to have rotatably mounted therein a guide pulley |22. may be mounted upon a suitable bali bearing assembly |24 for rotation within the housing |28. A removable end closure |28 is fixed to one side of the housing for the purpose of assembling the -bal1 bearing unit |24 and the pulleys |22.

The housing |28 is also provided with a trans- Such guidepuliey||2 verse guide opening |28 therein which is adapted to receive a bearing sleeve |30. Such bearing sleeve |30 slidably receives therethrougha guide rod |22, which is disposed substantially parallel to the axis of reciprocation of the member 88 and which has its ends fixed to the standard 32. The member 88 is thus xed against rotation but may reciprocate with respect to the spool |4.

'I'he cable 28 is received through suitable inlet and outlet openings provided within the housing |20, and is trained about the pulley |22.

It will be understood that the supply 88 illls the casing 84 on-one side of the piston 38 and also fills the chamber 84 and the chamber |0|. 'I'he oil supply 10 fills the casing 34 on the opposite side of the piston and also'lls the spaces 88, the conduit H8, the chamber 98, and the chamber |02.

As the spool I4 is driven, the sprocket wheel 54 is synchronously driven, thereby rotating the piston 38. Reciprocation of such piston is effected through the co-operation of the pins 80 with the groove 58. As the piston 38 is moved toward the right, viewing Figure 2, the fluid within the supply 88 and 84 is forced through the openings I2 into the chamber 0| The pressure of such iluid upon the wall portions |04 and |08 causes the member 88 to move to the left, viewing Figure 2. The fluid Within chamber |02 is then displaced into chamber 98 and passes through conduit ||8 into the supply portion T0 to fill the space left by the piston 84 in its movement toward the right. Conversely, the movement of the piston 84 toward the left, viewing Figure 2, will force the fluid from supply 10 through conduit ||8 into chamber 98 and through apertures ||4 into chamber |02, thereby causing movement of the member 88 toward the right, viewing Figure 2.

Constant rotation of the sprocket 54 in either direction thus causes reciprocation of the element 88 and guides the cable 28 between the ends of the spool |4 as it is being wound thereon or being unwound therefrom.

In order to insure movement of the element 88 to its limits, and to provide a slight overthrow so that the cable 28 is wound properly on the spool I4. resilient means are provided which are associated with the supplies 88 and 10 on the opposite sides of the piston in order to maintain pressures on such separate supplies.

The resilient means for acting upon the supply 88 comprises a disc-shaped member |34 disposed within the member 90 adjacent the outer end of the chamber 98. A resilient sealing cup |38 is fixed to the disc |34 and resiliently engages the inner peripheral surfaces of the member 90. A coil spring |38 engages the opposite face of the member |34, with the opposite end of the spring engaged by a closure plate |40 so as to exert a pressure upon the fluid within the chamber 95. An air vent |42 is provided through the member 90, communicating with the space beyond the member |34.

A similar structure is provided for communication with the supply 10 on the opposite side of the piston 38, and such structure is mounted within a cylindrical projected portion |44, which may be formed integral with the casing 34 and which communicates with the bore 38 in the supply portion 10 through a conduit |48. The disc, sealing cup, end member and vent are given the same numerals as immediately above to describe like parts, in that their action is the same except that they act upon the fluid in supply 10 through the conduit |48.

Referring to Figure 8, a modified form of the spooler, or level Winder, is shown which is generally indicated at |48. The same numerals are used to designate corresponding parts in this embodiment as are used above in connection with the embodiment shown in Figures 1 through '1.

A pair of axially aligned cylindrical members |50 is formed integral with the upper ends of the standards 32, and have facing open ends. Such members have cylindrical recessses or bores |52 therein which are adapted to telescopically receive the outer ends of the tubular members |54 and |58, respectively. Such members are complementary in shape to each other and correspond to the casing 34 in the embodiment above described. The members thus provide a cylindrical bore |82, within which a piston |84 is rotatably and slidably disposed.v Such piston |84 corresponds to the piston 38, above described, and has a similar groove 58 formed in the periphery thereof. A pin projects int'o the groove from the housing formed by sections |58 and |80, so that upon rotation of the piston |84 it is caused to reciprocate within the bore |82 through the co-operation of the pin 80 with the continuous groove 58.

An air vent |81 is provided in one of the members |50, and the other member |50, having the Wheel 54 attached thereto, may vent through the axial opening therein.

The sprocket wheel 54 is connected through a suitable stub'shaft |88, which projects through a sealed opening in the end of the` adjacent member |50 with an axially disposed drive member |10. Such drive member |10 has a cylindrical bore therein with a splined inner surface which is adapted to reciprocably receive therein the splined end of a shaft |12 which is formed integral with or otherwise suitably secured to one of the ends of the piston |84. Thus, the splined connection between the members |10 and |12 causes the piston |84 to rotate upon driving the sprocket wheel 54, but permits relative axial sliding movement therebetween.

Itwillthusbeseenthatasthepiston itlis caused to move to the left, viewing Figure 8, the fluid from within chamber Il! is displaced into chamber l, and causes the chamber Ill to expand, `thus moving the guide pulley |22 to the right, viewing Pleure 8. When the piston i moves toward the right, viewing Figure 8. itvwill be seen that the uid is displaced from the chamber i into chamber ill, causing the pulley |22 with the homing to move to the left, viewing Figure 8. As the huid is displaced from chamber |82. the iluid from chamber ill will pass into the chamber lll: and, conversely, when the iiuid is displaced from chamber i, the iluid from chamber il! will illl chamber |82.

In Figure 9, another modified form of the present invention is illustrated in which the spooling device, or level winder, is generally indicated at lll. Such spooling device ill is generally similar to that shown in Figure 2, except that the iluid chambers and piston means are of different form so that the overall length of the device is less than that of the embodiments described above and may thus be located in a smaller space.

The same reference numerals as used in the embodiment described in Figures 1 through 7 have been used here to indicate corresponding parts. It will thus be seen that the member 90 is mounted on the standards 32 and fixed against rotation with respect thereto. 'Ihe drive member l2 projects through one end thereof into one end oi' the member Il. It is then connected to a member Il2, which in structure is generally similar to the piston Il, vabove described. Such member |22 is formed with the groove 58 therein, which is engaged by a pin 6l to cause the reciprocation of the member |92- Such pin 6l, not shown in this embodiment, may project through an opening formed in the member 90 and be ilxed thereto. An air vent I may be provided vin the end of the member 90, so as to permit free axial movement of the member |92.

The member |92 has an integral, axially extending shaft III having spaced pistons |98 and i, secured to the outer ends thereof. That shaft portion 2li connecting the members |88 and i is preferably of a smaller diameter than the major shaft portion |96. 'Ihe members |98, i and shaft portion 2li are preferably formed separate from each other, so that they may readily be secured together and mounted within the member Il in the position shown.

Separate iluid chambers 2.2 and 204 are thus formed between the partitioning member 92 and piston III and piston |99, respectively. The supply chamber 2.2 communicates with the expansible chamber ill through the radial openings ||2; and the chamber 2 communicates with the chamber |l2 through the radial openings ill.

As the wheel M rotates, it will thus be seen that the pistons ill and |99 are caused to rcciprocate within the member 9|. When the pistons I and i" are moved to the left, viewing Figure 9, the iluid from chamber 2M passes into the chamber 2li and causes the housing 8B, together with the pulley |22 which carries the cable 2l, to move to the right, viewing Figure 9. When the pistons are moved in the opposite direction, the iluid enters chamber lill, causing the housing l. to move in the opposite direction.

'It will be appreciated, in all of the embodiments described above, that by properly proportioning the relative dimensions oi' the supply chambers such as Il and 0l with the volumes and conventional hydraulic system employing the.

necessary pump, check valves, needle valves, pilot valves and a four-way automatic valve, not only because such conventional system is more costly. but such system does not operate properly. The reason for this is that the pump, in such a systern, is not instantly responsive to the turning of the cable drum. A lag occurring while the pump is building up a working pressure would throw the reciprocating action out -of step with the revolving drum. 'Ihis could be caused by starting from a dead stop or by a loss of time in the operation of the check valves or the operation of pilot valves which, in turn, actuate the automatic valve before a start could be made at the actuating end of the circuit to move the piston and thus guide the cable across the face of the drum. For proper action, these movements must be timed exactly. In the conventional system mentioned it is not possible to overcome the time losses mentioned, especially with a slot turning pump.

What is claimed is:

l. In a device of the type described, a linearly movable element, a rotatable element, and means for moving said first-named element in a linear path in response to rotative movement of said second-named element, said last-named means including an hydraulic iiuid displacement system, said system including a casing containing separate supplies of fluid, piston means disposed within said casing for reciprocation and rotation therein to displace fluid within said casing in opposite directions therein, means forming opposite iluid chambers associated with said firstnamed element, and means communicating said separate supplies of fluid with said opposite fluid chambers, respectively, and means operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon rotation of said rotatable element.

2. In a device of the type described, a linearly movable element, a rotatable element, and means for moving said first-named element in a linear path in response to rotative movement of said second-named element, said last-named means including a closed hydraulic iiuid displacement system, said system including a casing containing separate supplies of fluid, piston means disposed within said casing for reciprocation and rotation therein to displace fluid within said casing in oppositel directions therein. means forming opposite fluid chambers associated with said first-named element, and means communieating said separate supplies of iluid with said opposite iluid chambers, respectively, and means operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon rotation of said rotatable element. 3. In a device of the type described, a linearly movable element, a rotatable element, and means for moving said ilrst-named element in a linear path in response to rotative movement of said second-named element, said last-named means including an hydraulic fluid displacement system, said system including a casing containing separate supplies of fluid, piston means disposed posite expansible and contractible iluidchambers i associated with said mst-named element, and means communicating said separate supplies of iiuid with said opposite fluid chambers, respectively, and means operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon rotation of said rotatable element to displace fluid in one direction within said `casing into one of said chambers, the lluid in the other chamber being displaced into the casing from the opposite direction. Y

4. In a device of the type described, a linearly movable element, a rotatable element, and means for moving said first-named element in a linear path in response to rotative movement of said second-named element, said last-named means including an hydraulic uid displacement system, said system including a casing containing a supply of fluid, piston means disposed within said casing for reciprocation and rotation therein to displace iluid within said casing on opposite sides of said piston means, means forming opposite expanslble and contractible uid chambers associated with said first-named element, and uid oonduits interconnecting the interior of said casing on opposite sides of said piston means with said opposite iluid chambers, respectively, and means operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon rotation of said rotatable element to displace fluid from one side of said piston means into one of said chambers, the fluid in the other chamber being displaced into said casing on the opposite side of said piston.

5. ln `a device of the type described, a linearly movable element, a rotatable element, and means for moving said rst-named element in a. linear path in response to rotative movement of said second-named element, said last-named means including an hydraulic fluid displacement system, said system including a casing containing a supply to fluid, piston means disposed within said casing for reciprocation and rotation therein to displace fluid within said casing in opposite directions therein, means forming opposite fluid chambers associated with said ilrst-named element, and means communicating the interior of said casing on separated sides of said piston means with said opposite fluid chambers, respectively, resilient means acting upon the fluid in said casing on opposite sides of said piston means to permit overthrow of said first-named element upon reaching the end of its travel, and means operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon rotation of said rotatable element.

6. In a device of the type described, a reciprocating element, a rotatable element, and means for reciprocating said ilrst-named element in response to rotation of said second-named element, said last-named moans including an hydraulic iluid displacement system, said system including a casing containing a supply of fluid, piston means disposed within said casing for reciprocation and rotation therein to displace iluid within said casing in opposite directions therein, means forming opposite fluid chambers associated with said ilrstnamed element, and means communicating the interior of said casing on separated sides of said piston means with said opposite iluid chambers, respectively, and means operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon4 rotation of said rotatable-element.

7. In a device ofthe type described, a reciprof eating element, a rotatable element, and means for reciprocating said first-named element in response to rotation of said second-named element, said last-named means including an hydraulic duid displacement system, said system including a casing containing a supply. of iluid, piston means disposed within said casing for reciprocaltion and rotation therein to displace fluid within said casing inopposite directions therein, means forming opposite expansible and contractlble fluid chambersl associated with said first-named element, and means communicating the interior ot said casing on separated sides of said piston means with said opposite fluid chambers, respectively, and means operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon rotation of said rotatable element to displace iluid in one direction within said casing into one of said chambers, the fluid in the other chamber being displacedinto the casing from the opposite direction.

8. A power winch construction comprising, in combination, a spool having a cable wound therearound, driving means for rotating said spool, a reciprocable guide element having a. cable receiving guide portion and movable longitudinally of said spool between the ends thereof, a rotatable element, means operatively connecting said rotatable element with said driving means for synchronous rotation therewith, and means for reciprocating said guide element in response to rotation of said rotatable element, said last named means including an hydraulic iluid displacement system, said system including a casing containing separate supplies of iluld, piston means disposed within said casing for reciprocation and rotation therein to displace fluid within said casing in opposite directions therein, means forming opposite uid chambers associated with said ilrst named element, and means communicating said separate supplies of fluid with said opposite uid chambers, respectively, and means operatively connecting said rotatable element with said piston means to rotate and reciprocate said piston means upon rotation of said rotatable element.

9. A power winch construction comprising, in combination, a spool having a cable wound therearound, driving means for rotating said spOol, a reciprocable guide element having a cable receiving guide portion and movable longitudinally of said spool between the ends thereof, a rotatable element, means operatively connecting said rotatable element with said driving means for synchr-cnous rotation therewith, and means for reciprocating said guide element in response to rotation of said rotatable element, said last named means including an hydraulic fluid displacement system, said system including a casing containing separate supplies of iiuid, piston means disposed within said casing for reciprocation and rotation therein to displace fluid Within said casing in opposite directions therein, means forming opposite expansible and contractible fluid chambers associated with said rst named element, and means communicating said separate supplies of uid with said opposite iluid chambers, respectively, and means operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon rotation of said rotatable element to displace iluid in one direction Within said casing into one of said chambers, the fluid in the other chamber being displaced into the casing from the opposite direction.

10. A power winch construction comprising, in combination, a spool having a cable wound therearound, driving means for rotating said spool, a reciprocable guide element having a cable receiving guide portion and movable longitudinally of said spool between the ends thereof, a rotatable element, means operatively connecting said rotatable element with said driving means for synchronous rotation therewith, and means for reciprocating said guide element in response to rotation oi said rotatable element, said last named means including an hydraulic iluid displacement system, said system including a casing containing a supply of fluid, piston means disposed within said casing for reciprocation and rotation therein to displace fluid within said casing on opposite sides of said piston means, means forming opposite expansible and contractible iluid chambers associated with said first named element, and iluid conduits interconnecting the interior of said casing on opposite sides of said piston means with said opposite iluld chambers respectively, vand means .operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon rotation of said rotatable element to dispiace iluid from one side of said piston means into one of said chambers, the duid in the other chamber being displaced into said casing on the' opposite side of said piston.

1l. A power winch construction comprising, in combination, a spool having a cable wound therearound, driving means for rotating said spool, a reciprocable guide element having a cable receiving guide portion and movable longitudinally of said spool between the ends thereof, a rotatable element, means operatively connecting said rotatable element with said driving means for synchronous rotation therewith, and means for reciprocating said guide element in response to rotation of said rotatable element, said last named means including an hydraulic fluid displacement system, said system including a casing containing a supply of iluid, piston means disposed within said casing for reciprocation ancl rotation therein to displace iluid within said casing in opposite directions therein, means forming opposite iluid chambers associated with said first named element, means communicating the interior of said casing on opposite sides of said piston with said opposite fluid chambers respectively, resilient means acting upon the fluid in said casing on opposite sides of said piston means to permit overthrow of said ilrst named element upon reaching the end o! its travel, and means operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon rotation of said rotatable element.

12. In a device of the type described, 'a linearly movable element, a rotatable element, and means for moving said first named element in a linear path in response to rotative movement of said second named element, said last named means including an hydraulic iluid displacement system, said system including a casing containing separate supplies oi' iluid, piston means disposed within said casing for reciprocation and rotation therein to displace iluid within said casing in opposite directions therein, means forming opposite iluidchambers associated wlthsaid nrst named element, means communicating said separate supplies of iluid with said opposite uid chambers, respectively, iluid reservoir means asmovable element. a rotatable element, and means tor moving said ilrst named element in a linear path in response to rotative movement of said second named element, said last named means including an hydraulic fluid displacement system, said system including a casing containing a supply of iluld, piston means disposed within said casing for reciprocation and rotation therein to displace :luid within said casing in opposite directions therein, means forming opposite duid chambers associated with said ilrst named element, and means communicating the interior ot said casing on opposite sides oi' said piston with saidv opposite iluid chambers, respectively, iluid reservoir means communicating with the interior of the casing von opposite sides of said piston, check valves interposed between said reservoir means and the interior of said casing on opposite sides of said piston, resilient means acting upon the iluld in said casing on opposite sides of said piston means to permit overthrow of said ilrst named element upon reaching the end of its travel, and means operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon rotation of said rotatable element.

14. A power winch` construction comprising, in combination, a spool having a cable wound therearound, driving means for rotating said spool, a reciprocable guide element having a cable receiving guide portion and movable longitudinally of said spool between the ends thereof, a rotatable element, means operatively connecting said roi said casing i'or reciprocation and rotation therein to displace iluid within said casing in opposite directions therein, means forming opposite iluid chambers associated with said first named element, and means communicating the interior of said casing on opposite sides of said piston with said opposite fluid chambers, respectively, fluid reservoirs communicating with the supply within said easing on opposite sides of said piston, check valves disposed between said reservoirs and said supply on opposite sides of said piston, resilient means acting upon the iluid in said casing onopposite sides ot said piston means `to permit overthrow of said rst named element upon 1 reaching the end of its travel, and means operatively connecting said rotatable element with said piston to rotate and reciprocate said piston upon rotation of said rotatable element.

EDWARD n BAaaE'rr.