Marine Winch

Abstract

The invention provides a marine winch driven by a central operating spindle coupled at its lower end to drive reduction gearing in turn coupled to an outer casing of the winch to rotate said casing at one of two alternative output ratios selectable on rotating the operating spindle in opposite directions. The operating spindle has a separate upper portion movable vertically relative to a lower portion and in splined driving engagement therewith. When the upper part of the operating spindle is lowered it is coupled directly to drive the outer casing so as to provide a third, 1:1, output ratio. Unidirectional stepless clutch means are provided in the drive lines to enable the three output ratios to be acheived and also to enable the outer casing to over run.

Description

This invention relates to a marine winch for hauling sheets, lifts, halyards and analogous tackle.

In U.S. Pat. specification No. 3711065 there is described a winch having a circular main casing adapted to be fixed to a deck and to be upstanding therefrom, and a winch drum is rotatable about the axis of an upper generally cylindrical turret of said casing. First unidirectional clutch means are operatively located between the drum and the turret and permit relative rotation between the drum and the turret in one direction only. A circular sub-casing has an upper sleeve portion extending through and coaxial with said turret and said sub-casing is rotatable about the axis of the turret. Second unidirectional clutch means are operatively located between the sleeve and the drum and permit relative rotation between said sleeve and said drum in a direction opposite to said one direction of rotation only. An operating spindle is located axially of the turret and rotatable relative thereto. Reduction gearing is adapted to transmit drive from said operating spindle to a flared circular lower part of said rotatable sub-casing, said gearing including two output gear wheels engaging diametrically opposite regions of a toothed ring formed within said flared circular lower portion of said rotatable sub-casing.

The reduction gearing is arranged to drive the output gear wheels in two ratios of say 3.5 : 1 and 11 : 1 selectable on rotating the operating spindle in opposite directions. To this end the operating spindle has at its lower end two drive wheels. A first one of these drive wheels is coupled to the spindle to rotate at all times therewith and said first wheel drives the two output wheels through two pairs of intermediate wheels, the wheels of each pair being coupled together through the medium of a third unidirectional clutch so that one wheel of the pair drives the other wheel of the pair in one direction only. The spindle is coupled to its second drive wheel through the medium of a fourth unidirectional clutch and said second drive wheel is, on diametrically opposite sides, in toothed engagement with the output wheels.

The unidirectional clutches employed are preferably sprag clutches operating between smooth coaxial cylindrical surfaces.

The winch drum and the sub-casing are supported for rotation on the main casing by roller bearings.

The present invention has for its particular object to provide a winch of the kind described in the aforementioned Specification augmented by an additional 1 : 1 gear ratio. To this end according to the present invention the drive spindle is modified to have a lower end part arranged to drive the reduction gearing exactly in the manner defined in the aforementioned specification, such lower end part being separate from an upper end part of the drive spindle, the upper and lower end parts of the spindle being provided with externally splined portions, both said splined portions being in splined engagement with an internally splined sleeve adapted to transmit drive from the upper end part to the lower end part of the spindle. Furthermore, the upper end part is movable axially relative to the lower end part of the spindle and is provided with driving dogs which upon axial movement of the upper end part of the spindle being effected, are movable into driving engagement with corresponding driven dogs on an annular element adapted to be fixedly attached to the winch outer casing on which the sheet or the line is adapted to be wound.

Preferably the upper spindle part is spring loaded upwardly so that its driving dogs tend to be urged out of engagement with the corresponding driven dogs on the annular element fixed to the winch outer casing.

Preferably also spring loaded ball catch means are provided for temporarily holding the upper part of the drive spindle either in its raised or its lowered position. In both positions the upper part of the drive spindle will be connected to drive the lower part of the drive spindle by the internally splined sleeve.

The invention will be described with reference to the accompanying drawings in which FIGS. 1 to 6 inclusive show the winch described in the aforementioned U.S. Pat. specification No. 3711065 while FIG. 7 shows the modification provided according to the present invention. More particularly with reference to the drawings:

FIGS. 1A and 1B are cross sectional views taken in the vertical plane passing through the centres of the two diametrically opposed output wheels, FIGS. 1A and 1B being views of the parts of the winch on the respective sides of its axis;

FIG. 2 is a perspective view partly cutaway illustrating the relative dispositions of the intermediate and output gear wheels;

FIG. 3 is a plan view on two levels illustrating the output drive path through the intermediate gears;

FIG. 4 is a perspective view illustrating the relative positions of the various gear wheels and their associated unidirectional clutches;

FIG. 5 is a diagrammatic plan view of a single unidirectional clutch;

FIG. 6 is a detail view of the clutch shown in FIG. 5.

FIG. 7 is a cross sectional view illustrating a modified arrangement provided according to the present invention whereby the winch is afforded a third 1 : 1 ratio.

In the drawings 1 generally represents a circular main casing member adapted to be fixed to a deck, rooftop or analogous component of a marine vessel. The main casing 1 has an upper generally cylindrical turret region 2 and flared bottom region 3 housing gearing means described below.

4 represents a baseplate secured to the flared bottom region 3 of the main casing 1.

A winch drum 6 is rotatable about the axis of the upper generally cylindrical turret 2 of the casing 1, its rotational movement being supported by roller bearings 7a, 7b and 7c.

In the drawing the winch drum 6 is a composite member formed by an internal sleeve 6a, and an external portion 6b shaped in conventional winch drum manner.

10 represents a first unidirectional clutch device operating between smooth cylindrical surfaces on the exterior of turret 2 and on the interior of the drum sleeve 6a respectively. Such first unidirectional clutch means 10 are effective to permit relative rotation between the drum 6 and the turret 2 in one direction only.

11 represents a circular sub-casing having an upper sleeve portion 11a extending through and coaxial with the turret 2. Splined on to the upper end portion of sleeve portion 11a and secured by a nut 16, is an annular abutment element 12, the sub-casing 11 and the abutment element 12 being supported for rotation about the axis of turret 2 by roller bearings 13 and 14.

The abutment element 12 has in its upper region a cylindrical surface 12a and between such surface and the internal cylindrical surface of the drum sleeve 6a there is operatively located second unidirectional clutch means 20.

21 represents an operating spindle located axially of the turret 2 and rotatable relative thereto, supported by an upper bearing assembly 21a and a lower bearing assembly 23 carried by baseplate 4.

At its upper end the operating spindle has a socket 24 shown in FIG. 2 for receiving a correspondingly shaped end of an operating lever. Its lower end is splined to a sleeve 21b.

The gearing mounted on baseplate 4 and within the lower flared part 3 of the casing 1 is adapted to transmit drive from the sleeve 21b splined to the operating spindle 21, to a flared lower portion 11b of the rotatable sub-casing 11. Such gearing essentially includes two output gear wheels 25 and 26 engaging diametrically opposite regions of a toothed ring 27 formed within the flared circular lower portion 11b of the sub-casing 11.

In the embodiment shown in FIGS. 1 to 6 the gearing is arranged to drive the output gear wheels 25 and 26 unidirectionally in one of two alternative ratios of say 3.5 : 1 and 11 : 1 and such alternative ratios are selectable on rotating the operating spindle 21 in opposite directions. To achieve this the operating spindle 21 has at its lower end two drive gear wheels 31 and 32.

The drive gear wheel 31 is integral with sleeve 21b and hence rotates at all times with the spindle 21. The wheel 31 drives the output wheels 25 and 26 through two pairs of intermediate gear assemblies, one of which is indicated generally at 33 in FIGS. 2 and 3.

Each intermediate gear assembly 33 comprises a large gear wheel 33a adapted to drive a smaller gear wheel 33b through the medium of a third unidirectional clutch means 30 located within the large wheel 33a.

Thus when the wheel 31 is driven in one direction drive is transmitted to wheel 33b while if the wheel 31 is rotated in the opposite direction, the unidirectional clutch 30 situated within wheel 33a will override, and relative rotation will be allowed between wheels 33a and 33b.

The smaller gear wheel 33b of the intermediate gear assembly 33 is in mesh with output drive wheel 25 (or 26) and the two assemblies 33 are located diametrically opposite one another within the lower flared part 3 of the main casing 1.

The seond drive wheel 32 is meshed directly with the output drive wheels 25 and 26. However, fourth unidirectional clutch means 40, in this case a pair of clutches, are operatively located to transmit drive to the wheel 32 from the spindle 21, such drive being transmitted only when the spindle 21 is rotated in the direction in which as described above, the third unidirectional clutch means within intermediate gear wheel 33a override. Ball race assemblies 22 support rotational movement of drive wheel 32 relative to operating spindle 21.

It will be appreciated from the above that when the spindle 21 is rotated in one direction, drive is taken through wheels 31, 31a, 33b, 25, 26 to tooth ring 27 while when the spindle is rotated in the opposite direction, drive is taken by way of fourth unidirectional clutch 40, toothed wheel 32, output drive wheels 25 and 26 to toothed ring 27.

Irrespective of the direction of rotation of spindle 21, the sub-casing 11 will be driven in only one direction. Rotation of the sub-casing 11 will, by way of second unidirectional clutch 20, be transmitted to winch drum 6, Winch drum 6 is prevented from reverse rotation relative to casing 1 by first unidirectional clutch 10. However, due to the presence of the second unidirectional clutch 20 the winch drum 6 can be rotated relative to sub-casing 11 in one direction only, for example, when manual hauling of the sheets, lifts, halyards or the like is required without resort to the mechanical advantage provided by the gearing.

The unidirectional clutches 10, 20, 30, 40 employed in the winch are preferably sprag clutches operating between smooth coaxial cylindrical surfaces.

FIG. 5 illustrates one of the intermediate gear assemblies 33 having a large gear wheel 33a arranged to rotate about a spindle 33c which is either rigidly attached to or integral with a gear wheel 33b (not shown in this Figure). Located between a cylindrical surface 33d of the large gear wheel 33a and the cylindrical surface of the spindle 33c is a unidirectional sprag clutch 30.

This is shown in detail in FIG. 6 and comprises a series of identical bone shaped sprag members 60 located in windows in three concentric locating rings 61, 62 and 63, the intermediate ring 62 of which may be of spring steel.

When the outer cylindrical surface 33d is rotated relative to the cylindrical surface of the spindle 33c in anticlockwise direction (referring to FIG. 6) the bone shaped sprag members are permitted by their locating rings to take up positions which are noticeably inclined to the radii of the assembly while when the surface 33d is rotated in the opposite direction the sprags tend towards taking up radial positions and are so shaped that they wedge between the surface 33d and the surface of spindle 33c preventing relative rotation between these surfaces.

It will be noted that when relative rotation takes place this will be substantially noiseless as compared with say, a ratchet system. Moreover, the sprags adopt their wedging conditions so rapidly that back play is obviated.

The gear trains are appropriately manufactured from stainless steel and due to their opposite diametrical dispositions there is cancellation of distortional torque effects.

It will be noted that the casing 1 and baseplate 4 themselves form a substantially closed chamber whose top is closed by the overhung winch drum 6 having screwed to it a cap member 50. The spindle 21 is supported for rotation within cap member 50 by the ball race 21a. Sealing is completed by seals 48, e.g. of neoprene and as a consequence, the interior of casing 1 will retain lubricant for substantially indefinite periods.

The winch as so far described with reference to FIGS. 1 to 6 has two alternative ratios selectable upon rotating the main spindle 21 either clockwise or anticlockwise.

The present invention has for its particular object to provide an additional 1 : 1 gear ratio. To this end according to the present invention the drive spindle is modified to have its lower end part arranged to drive the output gearing exactly in the manner described with reference to FIGS. 1 to 6, such lower end part being separate from an upper end portion of the drive spindle, the upper and lower end portions of the spindle being provided with external splines and there being an internally splined sleeve transmitting drive from the upper end part to the lower end part of the spindle. Furthermore, the upper end part is provided with driving dogs movable into driving engagement with corresponding driven dogs on an annular element adapted to be fixedly attached to the winch outer casing on which the sheet or the line is adapted to be wound.

This modified construction is shown in FIG. 7 of the accompanying drawings. In FIG. 7, 121 represents a lower part of a drive spindle adapted to be connected to drive two speed reduction gearing as described above.

Such lower spindle part 121 has an externally splined upper portion 121a. 131 generally represents an upper part of the drive spindle having at its lower end an externally splined portion 131a. 161 represents an internally splined sleeve transmitting drive from upper spindle part 131 to lower part 121 of the drive spindle.

171 represents a spring urging the upper spindle part 131 upwardly. 151 represents a further spring acting on two balls 141 and 142 adapted to engage in detents 143 provided internally of sleeve 161.

At its upper end, upper part 131 of the drive spindle has a head 131b in which is formed a socket indicated in dotted lines at 131c adapted to receive a correspondingly shaped end of an operating lever or winch handle (not shown).

Below the head 131b is an enlarged flange 131d having on its lower side driving dogs 131e. 200 represents an annular member adapted to be fixed to the winch casing 6, on which latter, the sheet or the like is adapted to be wound.

Annular member 200 has dogs 201 adapted to be engaged by the dogs 131e of the drive spindle 131 when the latter is in its lowered position. In this position rotation of upper spindle part 131 in one direction will effect rotation of the winch casing 6 provided that downward pressure is maintained upon the upper spindle part 131.

In this condition also rotation will be imparted to lower spindle part 121 which will drive the two speed reduction gearing described with reference to FIGS. 1 to 6. However, due to the over-running clutches provided in the two speed reduction gearing no driving torque will be transmitted through the two speed reduction gearing.

On the other hand as soon as downward pressure is removed from upper spindle part 131 spring 171 will urge upper spindle part 131 upwardly with the balls 141 and 142 engaging in the upper detents 143 in sleeve 161.

In this condition driving dogs 131e will become disengaged from the dogs 201 of annular element 200.

Means may be provided, for example seals, for limiting upward movement of upper spindle portion 131 relative to the annular element 200, and means will be provided for maintaining the sleeve 161 in splined engagement with lower spindle part 121.

In its upper position, rotational movement of upper spindle part 131 will be transmitted to lower spindle part 121 by way of the internally splined sleeve 161 and, dependent upon the direction of rotation of the spindle, the appropriate gearing will be selected of the two speed gearing, to effect unidirectional rotation of the winch casing 6 in one of two ratios.

Thus the present invention provides a three speed winch in which when the winch handle is inserted and pressed down, a 1 : 1 ratio is obtained, while, when the winch handle is in a raised position, two alternative ratios are available, dependent upon the direction of rotation of the winch handle.

The invention provides a winch which is substantially silent in operation, which has low friction and which provides alternative ratios of mechanical advantage and whose longevity is guaranteed due to the balancing of the torque distortion effects which would be created in the absence of duplication of the gearing in diametrically opposed fashion. Moreover, due to such balancing the cutting of the teeth of the various gears presents minimal problems.

Claims

1. A marine winch including in combination:

a. a casing adapted to be fixed to a deck to be upstanding therefrom, and having an upper generally cylindrical turret;

b. a winch drum rotatable about the axis of said upper generally cylindrical turret of said casing;

c. first unidirectional clutch means operatively located between the drum and the turret and permitting relative rotation between the drum and the turret in one direction only;

d. a circular sub-casing within the casing and having an upper sleeve portion extending through and coaxial with said turret, said sub-casing being rotatable about the axis of the turret;

e. second unidirectional clutch means operatively located between the sleeve and the drum, said second unidirectional clutch permitting relative rotation between said sleeve and said drum only in a direction opposite to said direction;

f. said circular sub-casing having a circular flared lower part and a toothed ring formed within said flared lower part;

g. an operating spindle located axially within the turret and rotatable relative thereto;

h. reduction gearing operatively connected to transmit drive from said operating spindle to said flared circular lower part of said rotatable sub-casing, said gearing including two output gear wheels engaging diametrically opposite regions of said toothed ring formed within said flared circular lower portion of said rotatable sub-casing, the said reduction gearing being arranged to drive the output gear wheels in two ratios selectable on rotating the operating spindle in opposite directions;

i. Characterised in that the operating spindle has a lower part arranged to drive the reduction gearing, such lower part being separate from an upper part of the drive spindle, the upper and lower parts of the spindle each being provided with externally splined portions, both said splined portions being surrounded by an internally splined sleeve fixed to the lower spindle part and adapted to transmit drive from the upper part to the lower part, and wherein the upper part is movable axially relative to the lower end part of the spindle, and of said sleeve, and is provided with driving dogs which, upon axial movement of the upper part of the spindle being effected, are movable into engagement with driven dogs on an annular element attached to the outer casing of the winch on which the

2. A marine winch according to claim 1 wherein the upper spindle part is spring loaded axially so that its drive dogs are urged out of engagement with the corresponding driven dogs on the annular element fixed to the

3. A marine winch according to claim 2, wherein spring loaded ball catch means are provided for temporarily holding the upper spindle part either in a raised position or in a lowered position and wherein, in both said position, the upper part of the drive spindle will be drivingly connected to the lower part of the spindle by means of the internally splined sleeve.