US3599937A

US3599937A - Winch

Info

Publication number: US3599937A
Application number: US799802A
Authority: US
Inventors: John Henry Carter
Original assignee: AEROMARINE CORP
Current assignee: AEROMARINE CORP
Priority date: 1969-02-17
Filing date: 1969-02-17
Publication date: 1971-08-17
Anticipated expiration: 1988-08-17

Abstract

A multiple-speed winch having a plurality of independently rotatable pinions coaxial with a drive shaft, drive linkages of varying mechanical advantage connecting these pinions to the winch drum and a shaft engager for engaging a selected pinion to the drive shaft. The shaft engager includes drive cams associated with the pinions and mounted for movement between an extended position which prevents relative rotation of pinion and shaft a retracted position which permits rotation; selective extension of the drive cams causes the shaft to drive selected pinions.

Description

United States Patent 1,413,292 4/1922 Rauscher lnventor John Henry Carter Weston, Mass. Appl. No. 799,802 Filed Feb. 17, 1969 Patented Aug. 17, 1971 Assignee Aeromarine Corporation Weston, Mass.

WINCH 6 Claims, 7 Drawing Figs.

Int. Cl. Field 0! Search References Cited UNITED STATES PATENTS 3,191,451 6/1965 Dluhosch 3,319,492 5/1967 Magnuson Primary Examiner-l-1arvey C. Hornsby Attorney-Martin Kirkpatrick ABSTRACT: A multiple-speed winch having a plurality of independently rotatable pinions coaxial with a drive shaft, drive linkages of varying mechanical advantage connecting these pinions to the winch drum and a shaft engager for engaging a selected pinion to the drive shaft. The shaft engager includes drive cams associated with the pinions and mounted for movement between an extended position which prevents relative rotation of pinion and shaft a retracted position which permits rotation; selective extension of the drive cams causes the shaft to drive selected pinions.

PATENTED AUG] 7 |97l @EEEEE U m 1 SHEEI 1 OF 3 lllllllllllllllll llll l| 1 I II PATENIED we: 7 |97| SHEET 2 OF 3 PATENTEU AUG 17 1971 3599.937

SHEET 3 [IF 3 .so that the high-speed shaft.

WINCH This invention relates to a multiple-speed winch.

The primary object of the inventionis to provide a winch having a selection of power ratios and provision for changing from one ratio to another. rapidly and conveniently even when the winch drum is underload. Another object of the invention is to provide such a winch which, with respect to its hauling capacity and mechanical strength is so lightweight and compact as to be excellently suited for use aboard high-performance sailboats.

The invention features a shaft engager for transmitting rotary motion of a drive shaft to any of a plurality of independently rotatable pinions coaxial with the shaft, the shaft engager including a plurality of drive cams each associated with a given pinion and mounted to the shaft for movement from a first extended positionengaging the associated pinion and preventing relative rotation between the pinion and the shaft (in at least one direction) to a second retracted-position permitting relative rotation, and means for selectively extending the drive cams and thus engaging the drive shaft to selected pinions.

In preferred embodiments, each pinion is associated with a drive linkage connecting it to an independently rotatable winch drum, the drive linkages being of varying mechanical advantage. The choice of the particular drive cams that are extended iscontrolled by the angular orientation of a rotatable cam-control rod within the drive shaft and coaxial with itLIT he drive shaft is freely rotatable in the reverse direction with respect to all the pinions (permitting the shaft to be cranked backwards without moving the winch drum, andalso permitting the winch drum to be "pulled through" in the forward direction (cg. by manually hauling in a line wrapped around the winch drum without rotating the drive shaft or crank). Three pinions are employed, a first (high-speed) pinion directly connected to the winch drum, a second mediumspeed pinion connected to the winch drum through a stepdown drive linkage, and a third low speed pinion connected to the drum through another stepdown drive linkagehaving a greater stepdown ratio. The winch .drum is positively prevented from rotating in a backward direction by a basernounted pawl mechanism. The winch drum is forwardly rotatable with respect to the lowspeed linkage, providing isolation of that linkage from the drum. Forstrength and lightness the body of the winch drum is made of cast nylon.

Other objects, features, and advantages will appear from the following description of a preferred embodiment of the invention taken together with the attached drawings thereof, in

which:

FIG. 1 is a perspective view of the entire winch;

FIG. 2 is an exploded isometric view of the driveshaft and shaft engager;

FIG. 3 shows diagrammatically the base, drive linkages, and portions of the drive shaft;

FIG. 4 is a sectional view taken on line 4-4 of FIG.11.

FIG. 5 is a sectional view ofithe pawl mechanism used to prevent reverse rotation of the winch drum taken online 5-5 of FIG. 3;

FIG. 6 is a sectional view of the drive shaft, drive cams, cam-control rod, and high-speed pinion taken on line 6-6 of FIG. 3 with the pinion engaged to the drive shaft;

FIG. 7 is a similar view but-with the cam-control rod rotated pinion is disengaged fromthedrive There is shown in FIG. .1 the winch drum 22 rotatably mounted to fixed base 24,'the drive shaft 26 concentric with the drum and also rotatable-with respect to base 24, crank 28 secured to the upper end of the drive shaft and provided with a handle 30. A similar crank (not shown) can be secured to the lower end of the drive shaft instead of (or inaddition to the upper crank (thus permitting below-deck operation of :the winch or two-handed operation).

pinion 34, and in drive-cam recesses 56 to Concentric with drive shaft 26 is high-speed pinion".32. (As used herein, pinion" is not intended to be limited to gears alone, but includes any comparable member driven by a rotating coaxial shaft. In the preferred embodiment, highspeed pinion 32 is directly keyed to thewinch drum 22 but it may, in other embodiments, be integral with the drum.)'Also concentric withdrive shaft 26 are medium- -s peed pinion 34 connected to the drum through a stepdown drive linkage (not shown), and low speed pinion 36 also connected to the drum through another stepdown drive linkage (not shown). When high-speed pinion 32 is engaged to shaft.36, each full rotation of crank 28 causes a full rotation of drum 22 with respect to base 24; when medium-speed pinion 34 is engaged to the shaft, 4.25 full rotations of crank 28 are required to produce a full rotation of the drum; when low speed pinion '36 is engaged to the-shaft, 11.05 full rotations of crank 28- are required to produce a'full rotation of the drum. Inthe preferred embodiment, the ratio of crank radius to drum radius is about 4.5 to

1. Consequently, the winch provides power ratios (mechanical advantages) of about 4,5, 19, and 50.

Referring to FIG. 2, the shaft 26 if keyed to crank-nut 40 by pins 42 cooperating with split-bores 43 and is further secured by retaining nut 44. Attachment of crank 28 to crank-nut 40 thus holds .shaft26 and crank 28 fixed with respect to each other. Shaft26 contains three sets of opposed drive-

cam recesses

52, 54, and 56, the two recesses of each set being apart on the drive shaft and the three sets of recesses being axially aligned. Drive-cams 62 with associated spring elements 62a are mounted in drive-cam recesses52 to permit the engagement of shaft 26 to high-speed pinion 32. Similar drive cams and spring elements (not shown) are mounted-in drive-cam recesses 54 to permit engagement of medium-speed permit engagement of low speed 'pinion 36.'Spacer 35 fixes the axial separation between pinions 34 and '36 and facilitates their rotation.

Cam-control rod'70 is inserted in axial bore 71 of drive shaft 26 and is rotatable within the drive shaft by means of control knob 73 secured to its upper end. Thecam-control rod is provided with three sets of opposed cam-

control grooves

72, 74, and'76, the two grooves of each set being 180 apart on the cam-control rod and the three sets of grooves 72 register with cams 62,'the cams are extended by spring. elements 620 (as shown in-FIG. 6) and high-speed pinion 32 is rotatably engaged to shaft 26. The earns 62 transmit forward (clockwise) rotation of the drive shaft 26 to internal teeth 33 of high-speed pinion 32, and keys 32a secure the pinion to winch drum 22 so that the drum-rotates with drive shaft 26 when crank 28 is forward rotated.

When cam control'rod70 is rotated an additional 60 camcontrol grooves 74 register with the corresponding pair of drive cams, causing 'the cams to be extended and engaging medium-speed pinion 34 to drive shaft 26. Because cams 62 no longer register with grooves 72, spring elements62a can no longer extend'the cams, and high-speedpinion '32 is disengaged'from the drive shaft (as shown inFIG. 7.). Mediumspeed pinion 34, when engaged to shaft 26, drives winch drum 22 through the medium-speed drive linkage, the stepdown gear train between pinion 34 and internal'ring gear 23 secured within drum '22 (see FIGS. '3 and 4).

A further 60 rotation of cam-control rod 70 causes camcontrol :grooves 76 to register with the corresponding pair of drive cams and extension of these cams engages low speed pinion 36 to drive shaft 26. Both high-speed pinion 32 and medium-speed pinion 34 are'then disengaged from the drive shaft. The low speed pinion drives winch drum 22 through the low speed drive linkage, the stepdowngear train between pinion 36 and internalring gear 23. Crank nut 49 is provided with notches 41 which cooperate with spring-loaded studs 45 within controlknob 73 (see FIG. 4).to ensure correct angular registration of the selected pair of drive cams withthe corresponding cam-control grooves on cam-control rod 70. Control knob 73 can be manually rotated to select the desired mechanical advantage even when the winch drum is under load, provided that no forward torque is applied to crank 28 while changing speeds. (Because of the pawl mechanism previously referred to, backward rotation of the loaded drum is prevented when application of torque to the drum is interrupted.)

FIG. 3 is a diagrammatic representation of the base, drive linkages, and portions of the drive shaft. Medium-speed pinion 34, when engaged to drive shaft 26, rotates clockwise causing idler 192 to drive gear 104, which in turn drives internal ring gear 23 (fixedly secured to winch drum 22). When the winch drum 22 is pulled through in the forward direction, gear 104, idler 102, and medium-speed pinion 34 are rotated by the drum, but the rotation of pinion 34 is not transmitted to drive shaft 26 or crank 28. The drive shaft is isolated from the pinion because the corresponding drive cams operate only in a forward direction and slip when the direction of relative shaft rotation is reversed (see FIG. 6). This isolation feature applies similarly to both the high and

low speed pinions

32 and 36. Forward rotation of either of these two pinions is also isolated from the drive shaft and crank. (There is a further, later to be described, isolation between the winch and the low-speed drive linkage.)

Pawl mechanism 110 prevents the winch drum 22 from rotating in a reverse (counterclockwise) direction. The details of pawl mechanism H are shown in FIG. 5. Internal ratchet 113 is fixedly secured to base 24. Pawl support 111 is coaxial with and secured to the underside of gear 104. Pawls 112 are spring-loaded by spring elements 1120 to engage internal ratchet 113, thereby permitting only forward (clockwise) rotation of the winch drum 22 and preventing reverse rotation. This feature is important in that when the winch is under load, the crank 28 can be released without permitting the load to back oil and without risk of the crank being accelerated by the load and thus endangering the operator.

Low speed pinion 36, when engaged to shaft 26, rotates clockwise, driving idler 120 which in turn drives one-way gear 122 clockwise. internal teeth 12 3 of one-way gear 122 engage pawls 125 secured to the underside of pinion 126, causing pinion 326 also to be driven clockwise and to transmit its forward rotation to internal ring gear 23 and thus to the winch drum 22. When the winch is pulled through in a forward direction, the pawls 125 do not engage one-way gear 122, and consequently the only portion of the low speed drive linkage that is caused to rotate is pinion 126; by reducing friction, this makes it easier to manually haul a line around the winch when no mechanical advantage is required.

Further structural features of the winch mechanism are shown in FIG. 4. The base 24 is fixedly secured to gear housing 25 which is in turn fixedly secured to vertical sleeve 27. Gear housing 25 provides a convenient mounting for the various elements of the medium and low speed drive linkages; sleeve 27 supports the drive shaft bearings (e.g. 92 and 94) and drum bearings (e.g. 96 and 98).

The winch drum body 93 is preferably made of cast nylon, sheathed by a protective metal shell 95 at those portions of the drum periphery most subject to wear from the lines to be hauled, and lined by a metal sleeve 99. Drum body 93 can be cast integrally with ring gear 23 (the outer surface of which is provided with threads 23a to prevent relative movement between the drum body and ring gear). Preferably, these threads, which are of low pitch, are roughened to reduce the chance of rotational movement of the gear with respect to the drum body and are oriented so that any torque which occurs when the winch is underload tends to bias the gear 23 into the drum body.

Proper choice of materials can greatly increase the strength and durability of the winch and can provide a significant reduction in weight for a given hauling capacity. For marine use, satisfactory results have been obtained by using a corrosion-resistant type 316" stainless steel for base 24, gear housing 25, and sleeve 27, and a harder high-strength type 7-4 PH" steel for drive shaft 26, cam-control rod 70, and the drive linkages. Yet stronger steels (e.g. type 440") can be employed where operating requirements so dictate.

The preferred embodiment described above and shown in the figures provided a three-speed winch, but obviously the same principles of construction and operation can be applied to other winches with a greater or lesser number of speeds and of widely varying size and hauling capacity. Further obvious modifications permit the winch to be converted readily to powered operation.

Other embodiments will occur to those skilled in the art and are within the following claims.

. What I claim is:

1. A multiple-speed winch comprising:

a rotatable drive shaft;

a coaxial, independently rotatable drum;

means to impart rotation secured to said drive shaft; a plurality of axially spaced pinions coaxial with said drive shaft and independently rotatably with respect thereto, said drive shaft extending through said pinions;

a plurality of drive linkages of varying mechanical advantage, each of said linkages being associated with one of said pinions and drivingly connecting said pinion to said drum;

a shaft engager adapted to selectively engage each of said pinions to said shaft to prevent relative rotation in at least one direction between said each pinion and said shaft, said shaft engager including a plurality of drive cams, each of said pinions being associated with at least one of said drive cams, and means for selectively extending said cams and thereby causing said drive shaft to selectively engage an associated pinion and thereby to drive said drum through the drive linkage associated with said pinion.

2. The multiple-speed winch of claim 1, further comprising means to prevent backward rotation of said drum.

3. The multiple-speed winch of claim 1 wherein one of said drive linkages has a mechanical advantage of unity.

4. The multiple-speed winch of claim 1 wherein portions of at least one of said drive linkages are isolated from said drum by one-way drive elements and are thus enabled to remain stationary when said drum is pulled through in a forward direction.

5. The multiple-speed winch of claim 1 wherein said drum comprises a nylon drum body.

6. A multiple-speed winch comprising:

a fixed base;

a drive shaft mounted for rotation upon said base;

a winch drum coaxial with said drive shaft and independently rotatable with respect to said base;

means secured to said drive shaft for imparting rotary motion thereto;

a plurality of axially spaced pinions coaxial with said drive shaft and independently rotatable with respect thereto, said drive shaft extending through said pinions;

a plurality of sets of drive cams, each of said sets having at least one cam and associated with one of said pinions, the cams comprised by each of said sets mounted to said shaft for movement from a first radially extended position, wherein said cams engage said associated pinion and prevent relative forward rotation of said shaft with respect to said pinion, to a second retracted position, wherein said cams do not engage said associated pinion and permit relative foreward rotation of said shaft with respect to said pinion;

a cam-control rod coaxial with said shaft and rotatable with respect thereto, the surface of said cam-control rod comprising a plurality of sets of cam-control grooves, each such set having at least one groove, adapted to be positioned to cooperate with an associated set of drive cams, and angularly spaced from each other such set of grooves;

the position assumed by the drive cams comprised by each set of drive cams being controlled by the angular position radially extended position, to engage the associated pinion, and, through the associated drive linkage, to drive said drum;

whereby the angular position of said cam-control rod selects the mechanical advantage of said multiple-speed winch.

Patent No. 3,599,937 Dated August 17, 197

InventoflX) John Henry Carter It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In the Abstract, line 8, after "shaft" add "and";

Column 2, line 11, "36" should be "26";

Column 2, line 20, "L5" should be 4.5";

Column 2, line ll, after "grooves" add "being spaced 60 apart. when the cam-control rod is rotated so that grooves";

Column 2, line 67, 49" should be 40";

Column 3, line 21, after "winch" add "drum"; Column 3, line 71, "7-H" should be "17- 4";

Column 4, claim 6, line 65, "foreward" should be "forward";

Column 5, claim 6, line 3, ositionv'i'should read positions Signed and sealed this 14th day of March 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents

Claims

1. A multiple-speed winch comprising: a rotatable drive shaft; a coaxial, independently rotatable drum; means to impart rotation secured to said drive shaft; a plurality of axially spaced pinions coaxial with said drive shaft and independently rotatably with respect thereto, said drive shaft extending through said pinions; a plurality of drive linkages of varying mechanical advantage, each of said linkages being associated with one of said pinions and drivingly connecting said pinion to said drum; a shaft engager adapted to selectively engage each of said pinions to said shaft to prevent relative rotation in at least one direction between said each pinion and said shaft, said shaft engager including a plurality of drive cams, each of said pinions being associated with at least one of said drive cams, and means for selectively extending said cams and thereby causing said drive shaft to selectively engage an associated pinion and thereby to drive said drum through the drive linkage associated with said pinion.

5. The multiple-speed winch of claim 1 wherein said drum comprises a nylon drum body. 6. A multiple-speed winch comprising: a fixed base; a drive shaft mounted for rotation upon said base; a winch drum coaxial with said drive shaft and independently rotatable with respect to said base; means secured to said drive shaft for imparting rotary mOtion thereto; a plurality of axially spaced pinions coaxial with said drive shaft and independently rotatable with respect thereto, said drive shaft extending through said pinions; a plurality of drive linkages of varying mechanical advantage, each of said linkages being associated with one of said pinions and drivingly connecting said pinion to said drum; a plurality of sets of drive cams, each of said sets having at least one cam and associated with one of said pinions, the cams comprised by each of said sets mounted to said shaft for movement from a first radially extended position, wherein said cams engage said associated pinion and prevent relative forward rotation of said shaft with respect to said pinion, to a second retracted position, wherein said cams do not engage said associated pinion and permit relative foreward rotation of said shaft with respect to said pinion; a cam-control rod coaxial with said shaft and rotatable with respect thereto, the surface of said cam-control rod comprising a plurality of sets of cam-control grooves, each such set having at least one groove, adapted to be positioned to cooperate with an associated set of drive cams, and angularly spaced from each other such set of grooves; the position assumed by the drive cams comprised by each set of drive cams being controlled by the angular position of said cam-control rod, said cam-control rod being rotatable to a plurality of predetermined positions, each of said predetermined position being such as to bring the cams in a selected set of drive cams into angular registration with the grooves in the associated set of cam-control grooves, thereby causing said cams to move to said first radially extended position, to engage the associated pinion, and, through the associated drive linkage, to drive said drum; whereby the angular position of said cam-control rod selects the mechanical advantage of said multiple-speed winch.