GB2233623A - Rope winch - Google Patents

Abstract

A rope winch (10) includes a motorised rotating sheave (20) around which a rope (1) extends. A pivot member (114) with two projections, an impingement arm (115) and a stripper arm (110), pivots into a groove (34) of the sheave (20). The pivot member (114) is spring-biased to urge the impingement arm (115) toward the inside of the groove (34). The impingement arm (115) urges the tail end of the rope (1) into the groove (34) during paying out of an anchor. When the anchor is hauled in, the stripper arm (110) blocks the tail end of the rope (11) from staying in the groove (34) where it would foul the winch (10). The stripper arm (110) directs the tail end of the rope to the proper opening in the winch (10). <IMAGE>

Description

ROPE WINCH The present invention relates to winches, such as a winch for paying out and hauling in the tail of a rope under the load of a boat anchor or other similar load.

Numerous winches are available for raising and lowering boat anchors. Most require supervision for several reasons. First, the rope tends to slip from the winch, especially when it is hauling in the anchor. Second, during the paying out, the rope can remain in the winch and tangle there. Supervision is necessary to prevent those occurrences.

According to one aspect of the invention, there is provided a winch which has a housing, and a pair of openings into the housing. The loaded end of the rope passes through one opening, and the unloaded rope tail passes through the other opening. The rope passes around a sheave, which rotates through a motor and gear drive alternatively clockwise and counterclockwise.

The sheave has an inwardly tapered circumference groove.

According to a second aspect of the invention, there is provided a winch comprising a sheave mounted for rotation about an axis, two rope guides positioned to lead a loaded end and an unloaded end of a rope to and from the sheave, and a pivot member pivotable about a pivot axis extending substantially parallel to the sheave axis, said pivot member comprising a stripper arm extending into the sheave toward the centre of the sheave and an impingement arm extending substantially tangentially to the periphery of the sheave and having an impingement projection extending into the sheave, and there being means for biasing the impingement projection toward the sheave.

In one embodiment of the invention, channels lead from the openings to the sheave to direct the opposite ends of the rope to opposite sides of the sheave. The channel leading to the anchor is tangential with the outside of the sheave; the channel for the tail section is generally radial with the sheave. A pivot member next to the sheave has a stripper arm and an impingement arm on it. The pivot member is springbiased toward the centre of the sheave. When the sheave rotates to haul in the anchor, one side of the stripper arm strips the rope tail off the sheave so that the sheave does not foul the winch. When the anchor is paid out, the impingement arm pushes the loose tail end toward the centre of the sheave so that the sheave engages the rope.At the same time, the other side of the stripper arm combats any tendency for the loaded end of the rope to stay within the sheave and foul the winch.

The inner tapered walls of the sheave may have substantially radial grooves or ribs, which tend to draw the rope into the sheave when it rotates against the load in one direction and tends to expel the rope when the sheave rotates in the opposite direction.

Certain embodiments of the invention can be so designed so as to provide a rope winch particularly suited as an anchor winch for use on a boat to raise and lower an anchor, and in so doing, to feed an unloaded tail section of anchor rope clear of the winch without fouling, and thus taking into account the fact that there is a load on one end of the rope but none on the other end (except for the weight of the rope).

Prior art devices cannot compensate for the differences in load when the winch rotates in opposite directions to pay out or haul in the anchor.

For a better understanding of the present invention and as to how the same may be carried into effect, reference will now be made by way of example to the accompanying drawings in which: Figure 1 is a top view, partially cut away of a rope winch; Figure 2 is a side sectional view taken through broken planes 2-2 in Figure 1; Figure 3 is a detailed top sectional view showing the way in which the rope passes around a sheave; Figure 4 is a sectional view taken through plane 4-4 of Figure 3, also showing how the rope and sheave interact; Figure 5 is a sectional view taken through the plane 5-5 of Figure 3, showing the construction of the pivot member and the rope guide (bridge).

A rope winch 10 has a housing 12 formed of a cover 14 and base 16. The base and cover are both formed of noh-corrosive material. Because the cover is removable, it should be lightweight. Base 16 is shaped as shown in Figure 1 to create a variety of cavities and mounting regions for the internal parts.

A sheave is mounted for rotation within the housing. In the exemplary embodiment, sheave 20 is formed of two circular jaws 22 and 24 (Figures 2-4).

Each jaw has facing surfaces 26 and 28 which taper toward each other from the outside 30 toward the inside 32. The jaws 26 and 28 form a circumferential groove 34, which is best seen in Figure 4. Tapered surfaces 26 and 28 may have circumferentially spaced curved ribs 27 and 29 (Figures 3 and 4). Ribs 27 and 29 are curved and may be spaced apart to engage the helices of a typical anchor rope to provide additional gripping of the rope within the sheave.

Motor 36 (Figure 2) is mounted in housing 16.

Bolt 40 attaches motor 36 to gear box 38, and bolt 42 secures the gear box to base 16. A worm (not shown) within gear box 38 drives gear 44. Gear 44 is fixed to shaft 46 by key 50 on shaft 46 and by clips 48. Key 52 on the shaft secures upper and lower jaws 22 and 24 to shaft 46.

The top of gear 44 supports the bottom of lower jaw 24 within a groove 54 (Figures 2 and 4). Spacer 56 is mounted above upper jaw 22. The spacer is provided so that a wider range of rope diameters can be accommodated. As shown, with the spacer on top, ropes having diameters of 1/2 inch to 5/8 inch (1.27-1.59 cm) can be accommodated. If the jaws are re-assembled with the spacer between the jaws, ropes having a diameter of 5/8 inch to 3/4 inch (1.59-1.91 cm) can be accommodated. Clips 58 and 60 above the spacer and lower jaw provide axial positioning of the jaws 22 and 24 on shaft 46. Bolts 64 (Figures 1 and 2) secure the jaws together. Lubricated pads 66 and 68 or other bearings provide spacing and minimize friction between gear 46 and base 16. Seals 70 and 72 prevent contaminants from entering the gear box 38.

The rope winch is intended to be attached to a boat in such a manner that the sheave 20 is parallel to the surface of the water and the shaft 46 is perpendicular to the surface of the water.

The rope winch has a pair of openings in its housing. In the exemplary embodiment, opening 76 (Figure 1) is positioned horizontally from sheave 20 and extends through cover 14. Opening 76 leads to tubular rope guide 96 which guides the rope tail to and from the sheave 20. The second opening 78 extends down from the housing (Figures 1 and 2). Opening 78 leads to a second tubular rope guide 98 which guides the loaded end of the rope to and from the sheave 20. The anchor rope 1 has a free or tail end 2 and a loaded end 3 connected to an anchor (not shown). The anchor end of the rope extends generally horizontally through opening 76 where the weight of the anchor maintains the loaded end 3 under tension. At a distance from the rope winch, the anchor end of the rope is led over the side of the boat and into the water.As rope winch 10 is intended to be mounted on a boat deck 4, lower opening 78 is aligned with or fits within an opening in the deck 4 so that the tail end 2 of the rope passes through opening 78, into a bucket or storage locker below the deck.

A pair of solenoids 80 and 82 (Figures 1 and 2) are mounted within a chamber 84 formed by base 16. The solenoids control the reversing of motor 36 in a conventional manner. An external control (not shown) in the form of a switch, push buttons or other manually operated member mounted on cover 14 acts through solenoids 80 and 82 to control motor 36.

Screw 88 secures toggle latch assembly 90 to base 16, and screw 92 secures the toggle latch assembly to cover 14 (Figure 2). The toggle latch assembly has a cover 94 (Figures 1 and 2) that can lock on the lower portion of the toggle latch assembly. When cover 94 is unlocked as shown in Figure 2, one can remove screws 88 and 92 and thereby remove cover 14 from base 16 to allow access to internal parts.

A first and second guide means extend from openings 76 and 78 in the housing to sheave 20. In the exemplary embodiment, the guide means are two tubular channels 96 and 98 which are formed as part of or otherwise attached to base 16.

As Figure 2 shows, guide or channel 96 is generally horizontal and tangential with one side of sheave 20. Axis 100 of the other guide 98 projects through the axis 102 (Figure 1) of sheave 20 in the exemplary embodiment. It is not crucial that axis 100 actually intersect axis 102, but whereas guide 96 is spaced to the peripheral (Figure 1) of sheave 20, guide 98 is much more centrally located. Guide 98 is bent downward so that it directs the tail end of rope 2 through opening 78 and through deck 4.

The winch has a pivot member 114. Pivot member 114 has two arms, an impingement arm 115 and stripper arm 110. It is possible to have a fixed stripper arm to strip the rope out of the sheave as it comes off of the sheave in either direction, either pulling in the anchor or letting it out. It is also possible for the winch to be provided with a biased roller or impingement member which serves to impinge or push the rope into the sheave in order to increase the amount of contact between the rope and sheave to produce sufficient friction to assist in the winch's operation.

Such an impingement member could be a pivoted member which is biased, such as spring-biased, to push and hold the rope in the sheave.

Because of the two goals and purposes served by a fixed stripper member and a pivoted impingement member, two separate members would be required to be designed into a rope winch. However, because of the desire to make rope winches smaller and simpler in design, it is desirable to reduce the number of separate members in the design of a rope winch. The single pivot member 114 serves both the function of a fixed stripper member and a pivoted impingement member in one integral piece.

These functions are accomplished by pivoting the pivot member closely adjacent the periphery of the sheave 20 at 118, and providing a stripper arm 114 which extends in a direction toward the axis of the sheave 20. The stripper arm 110 is relatively short compared to the impingement arm 114. The impingement arm 114 is integral with the pivot member 115 and is generally elongated and extends in a direction substantially tangential to the periphery of the sheave 20. At the end of the impingement arm 114 there is provided an integral impingement projection 112 which extends generally towards the centre of the sheave 20 In the preferred embodiment, the impingement projection 112 is a solid member with a smooth surface so as not to abrade the rope, although it could include a roller.

The impingement arm 114 is provided with a bridge 116 which is shaped so as to pass over the rope, looking down on Figure 1, and encircle the major portion of the rope 1 as it passes underneath the pivot member 115. Thus pivot member 115 also serves as a rope guide leading the rope 1 either onto or off the sheave 20, and acts as an extension of the rope guide 98.

Pivot member 114 pivots on pin 118, which is attached to base 16 (Figure 2). Spring 120 extends between tensioner screw 126, which passes through post 122 and tension pin 124 through pivot member 114.

Adjustment of tensioner screw 126 relative to post 122 changes the tension of spring 120. The spring 120 biases pivot member 114 counterclockwise in Figure 1 to urge impingement projection 112 toward the inside of circumferential groove 34 of sheave 20. A wall 128 surrounds much of the sheave to maintain any loose section of the rope in the sheave.

The device operates in the following fashion.

Rope 1 from the anchor extends through opening 76 and guide 96 into the circumferential groove 34 of sheave 20. The rope continues around the sheave and passes between impingement projection 112 and stripper arm 110 and then exits the circumferential groove as shown in Figure 1. The rope next passes rope guide or bridge 116 (see Figure 5) in pivot member 114 and then extends through guide 98 out opening 78. When the anchor is paid out, the sheave rotates counterclockwise (Figure 1). Thus, the tail end of the rope is withdrawn from the storage locker or bucket and it moves through opening 78 and guide 98 toward circumferential groove 34 of sheave 20. Pivot member 114 is biased in a counterclockwise direction about pin 118 to urge impingement projection 112 toward the inside 32 of groove 34.The impingement projection contacts the rope and pushes it toward the inside of the groove where it is frictionally held by tapered surfaces 26 and 28.

However, in the event the tail of the rope is restricted, tangled, or blocked in any way in being pulled out of the locker and into the sheave, the pivot member 115 is constructed in such a way as to then allow the sheave and rope to slip relative to each other. This is accomplished by the fact that the impingement projection projects into the sheave below the imaginary line connecting the point at which the rope exits under the rope guide 116 and the tangential point at the periphery of the sheave. Any restrictions or blockage affecting the free paying out of the rope will increase the tension in the rope which will overcome the biasing force of the impingement arm and thereby allow the rope to partially lift out of the groove 34 of the sheave 20. This will reduce the frictional contact between the rope and sheave and allow slippage, thereby avoiding damage to the winch or boat.

Tension from the weight of the anchor causes that portion of the loaded end 3 of rope 1 in the groove to be pulled from the groove as the anchor end of the rope is paid out. If the rope sticks in the groove, however, stripper arm 110 blocks the rope and strips it out of the sheave.

During the hauling in operation, motor 36 and gear box 38 rotate sheave 20 clockwise. Tension on anchor end 2 of rope 1 urges the rope into the circumferential groove where it passes around sheave 20. The only force pulling the tail end 2 of rope 1 through guide 98 and opening 78 is the weight of the rope, which normally is very minimal. Therefore, there can be a tendency for the tail end of the rope not to withdraw itself from groove 34. Of course, if the rope stayed within the groove, it would continue around sheave 20 where it would intersect the incoming loaded anchor end 3 of the rope to foul the winch. Any tendency of the rope to stay within the groove is overcome by stripper arm 110. It intersects any part of the tail end of the rope that stays within groove 34 and directs it toward rope guide 116 and guide 98 (Figure 1).

When sheave 20 is rotating clockwise, and thus lifting the anchor, the bias of spring 120 ensures that impingement projection 112 is pressing the rope into the sheave. This ensures that there is sufficient contact or engagement of the rope in the sheave to transmit enough torque to initially haul the rope in while there may well be a considerable amount of slack rope before the load is taken up. On taking up the slack, the rope 3 is forced into the groove by the load and contact is made around the sheave, providing sufficient grip on the rope to allow the full torque developed to be transmitted to the rope without slipping.

When the sheave 20 is rotating in a counter clockwise direction, i.e. when lowering the anchor, the bias ensures there is enough grip to transmit the torque required to lift the rope from the locker and drive it out through channel, 96, to launch and lower the anchor.

If, for some reason, when launching or lowering the anchor, the rope becomes jammed or tangled in the locker, or at the inlet in channel 98, the rope tightens so that it tends to become tangential to the sheave between the sheave and channel 98. This tightening moves the impingement projection 112 outward against the bias. In doing so, this releases the grip of the sheave on the rope. This allows the drive to slip and thus stop a jam up.

In the exemplary embodiment, the guides 96 and 98 are positioned such that the rope is engaged in the groove of the sheave through a substantial arc. This maximizes the gripping that the tapered surfaces 26 and 28 act on the rope.

Those skilled in the art may make numerous uses of and modifications to the present invention without departing from its principles.

Claims (9)

1. A winch comprising a sheave mounted for rotation about an axis, two rope guides positioned to lead a loaded end and an unloaded end of a rope to and from the sheave, and a pivot member pivotable about a pivot axis extending substantially parallel to the sheave axis, said pivot member comprising a stripper arm extending into the sheave toward the centre of the sheave and an impingement arm extending substantially tangentially to the periphery of the sheave and having an impingement projection extending into the sheave, and there being means for biasing the impingement projection toward the sheave.

2. A winch as claimed in Claim 1, wherein the pivot member is provided with a rope guide passage located between the pivot axis and the impingement projection, said passage serving as a rope guide between the rope guide for the unloaded end and the sheave.

3. A winch as claimed in Claim 2, wherein the impingement projection extends into the sheave below the line connecting the point at which the rope leaves the rope guide on the pivot member and the tangential point on the periphery of the sheave so that upon increased tension in the rope the rope will act against the biasing force of the impingement arm and partially lift out of the groove of the sheave.

4. A winch as claimed in any one of the Claims 1 to 3, wherein the stripper arm and the impingement arm are coupled together against movement relative to one another.

5. A winch as claimed in Claim 4, wherein the stripper arm and the impingement arm are integral.

6. A winch as claimed in any one of Claims 1 to 5, wherein the impingement arm is relatively long compared with the stripper arm.

7. A winch as claimed in any one of Claims 1 to 6, wherein said pivot member axis is located in the region between a periphery of the sheave and the exit/entrance of the rope guides.

8. A winch as claimed in any one of Claims 1 to 7, wherein the pivot axis, in use, lies in the region defined on the one side by the rope where it leaves one rope guide and enter the sheave and on the opposite side by the rope where it exits the sheave and enters the other rope guide.

9. A winch substantially as hereinbefore, described with reference to the accompanying drawings.