Portable winch

Abstract

 A portable winch (10) with an internal combustion engine (16) a line feeding mechanism (14) for paying out and drawing in a line, and controllable gearing (20) for coupling the engine to drive the line feeding mechanism to selectively either pay out or draw in the line, is described.

Description

[0001] This invention relates to portable winches.

[0002] Typically a winch is mounted in a fixed position and includes a motor-driven drum for spooling in a cable. A free end of the cable may then be used to haul or hoist an object. Conversely, the free end may be attached to a fixed object, while the winch is mounted on the object which is to be hauled or hoisted. For example, the winch may be mounted on a truck and the cable attached to a distant tree trunk for the purpose of pulling the truck out of a mud hole. Once the truck is pulled from the mud, the tension in the cable is typically relieved by a clutch mechanism which releases the drum from the drive mechanism and allows the drum to rotate freely, thus paying out the cable.

[0003] In general, in one aspect, the invention features a portable winch having an internal combustion engine, a line feeding mechanism for paying out or drawing in a line, and controllable gearing for coupling the engine to drive the line feeding mechanism to selectively either pay out or draw in the line.

[0004] Preferred embodiments of the invention include the following features. The controllable gearing includes a planetary gear train with an inner driving sun gear, an outer ring gear, planet gears disposed between and engaging the inner driving sun gear and the outer ring gear, and a mechanism for selectively either interlocking the motion of the driving sun gear with the outer ring gear, or permitting relative rotation of the driving sun gear and the outer ring gear in opposite directions. The mechanism includes shafts on which the planet gears are mounted, and the outer ring gear comprises bores for receiving the shafts, the shafts being movable axially from a position in which they are engaged in the bores and the motion of the driving sun gear is interlocked with the outer ring gear, to a position in which they are disengaged from the bores and relative rotation of the driving sun gear and the outer ring gear in opposite directions is permitted. The ring gear has an outer driving surface, and a drive belt couples the outer surface of the ring gear to a drive pulley. The line feeding mechanism comprises a drum and the engine comprises a non-reversing gasoline powered engine. A lever moves the shafts between the two positions, and an omega-shaped spring biases the lever to move to either of two positions.

[0005] As a result, when a hoisting or hauling job is finished, the tension in the line can be released in a controlled manner by driving the drum so that the line is paid out, thus preventing the line from being pulled off the drum uncontrollably. A non-reversing light-weight gasoline engine can be used, making the winch portable. The lever permits easy reversing of the drum rotation, even when the mechanism becomes too hot to touch.

[0006] Other advantages and features will become apparent from the following description of the preferred embodiment.

[0007] Fig. 1 is a top view partially cutaway of a portable winch constructed in accordance with this invention.

[0008] Figs. 2A and 2B are respectively sectional views at 2A-2A and 2B-2B of Fig. 1 with the planet carrier respectively in the pushed-in position and the pulled-out position.

[0009] Fig. 3A, 3B, 3C, and 3D are respectively side views (in the "in" position and in the "out" position) and top views (in the "in" position and in the "out" position) of an actuator plate and omega spring.

[0010] Referring to Fig. 1, a portable winch 10 has a steel cable 12 which can be drawn onto and paid out from a generally cylindrical (slightly conical) drum 14. To apply pulling tension to the cable 12, a small, lightweight, non-reversible gasoline engine 16 (similar to a chain saw motor) drives the drum 14 via a rubber belt 18. The engine 16 drives the belt 18 through gearing 20. The gearing 20 can also reverse the direction of rotation of the drum 14 to pay out the cable 12. The gearing 20 is located between an engine drive shaft 22 and a belt driver pulley 24 to which the belt 18 is coupled.

[0011] As shown in Figs. 2A and 2B, the position of a planet carrier 26 controls the direction of rotation of the belt 18. With the planet carrier 26 in the pushed-in position (Fig. 2A), the gearing 20 causes forward driving or pulling in of the cable 12. With the planet carrier 26 in the pulled-out or disengaged position (Fig. 2B), the gearing 20 causes reverse driving or paying out of the cable.

[0012] Referring to Fig. 2A, the belt driver pulley 24 and the belt 18 are driven in the forward or pulling direction by four planet gears 28 (only two of them are seen in the Figures). The planet gears 28 are driven by a sun gear 30 which is attached to the engine drive shaft 22. The planet gears 28 rotate on shafts 32 that are rigidly connected to the planet carrier 26 and the teeth of the planet gears 28 engage the teeth of a ring gear 34 whose outer surface is the belt driver pulley 24. In the pulling mode, the planet carrier 26 is pushed in or engaged so the shafts 32 of the planet gears 28 are locked into bores 35 in the ring gear 34. In this mode, the planet carrier 26, the belt driver pulley 24/ring gear 34 combination, the sun gear 30, and the engine drive shaft 22 all drive in the same direction 36 to draw in the cable 12.

[0013] Referring to Fig. 2B, the belt driver pulley 24 and the belt 18 are driven in the reverse or pay out direction by the four planet gears 28 operating in the pay-out mode. As in the pulling mode, the planet gears 28 are driven by the sun gear 30, rotate on shafts 32, and operate in the ring gear 34. However, in the pay-out mode, the planet carrier 26 is pulled out or disengaged so the shafts 32 of the planet gears 28 are withdrawn from the bores 35 in the ring gear 34. In this mode, the pulled-out planet carrier 26 does not rotate. The withdrawal of the shafts 32 from the bores 35 in the ring gear 34 causes the planet gears 28 and the ring gear 34/belt driver pulley 24 combination to drive in a direction 37 opposite the direction 36 described for the pulling mode. Rotation in this direction 37 results in pay out of the cable 12. Note that the engine 16 itself is not reversible and so the sun gear 30 and the engine drive shaft 22 continue to drive in the same direction 36 described for the pulling mode while the planet gears 28 and the ring gear 34/belt driver pulley 24 combination drive in the opposite direction 37.

[0014] As shown in Figs. 3A, 3B, 3C, and 3D, an actuator plate 38 may be manually moved by an operator in order to position the planet carrier 26 into either of its two positions. The actuator plate 38 is secured to an engine mount 40 and pivots about the mount 40 when manually moved into one of its two positions. An omega-shaped spring 42 located between the actuator plate 38 and a side plate 44 on the winch 10 provides biasing forces to hold the actuator plate 38 in the position selected by the operator.

[0015] Referring to Figs. 3A and 3C, with the actuator plate 38 in the "in" position, the planet carrier 26 is pushed in or engaged and the cable 12 is drawn in as previously described.

[0016] Referring to Figs. 3B and 3D, with the actuator plate 38 in the "out" position, the planet carrier 26 is pulled out or disengaged and the cable 12 is paid out as described above. Two camming fingers 46 on the actuator plate 38 force the planet carrier 26 to pull out when the actuator plate is moved into the "out" position. Once fully in the "out" position, a stopping latch 48 on the actuator plate 38 stops the planet carrier 26 from rotating by contacting one of the shafts 32.

[0017] Regardless of the position of the planet carrier 26, the engine 16 may be started and run at idle speed without drawing in or paying out the cable 12 by means of a centrifugal clutch 50. The centrifugal clutch 50 has a clutch cup 52 fixed to the sun gear 30 as shown in Figs. 2A and 2B. Referring to Figs. 2A and 2B, with the engine 16 at idle speed, the centrifugal clutch 50 is disengaged and the engine drive shaft 22 does not drive the sun gear 30. When the engine 16 reaches a suitable speed, centrifugal force causes the centrifugal clutch 50 to engage the clutch cup 52. With the clutch cup 52 engaged, the engine drive shaft 22 drives the sun gear 30 and the cable 12 is drawn in or paid out depending on the position of the planet carrier 26 as described above. The clutch cup 52 is fitted with a self-lubricated bearing 54 to allow rotation about the engine drive shaft 22. A self-lubricated bearing 56 is also used in the center of the ring gear 34 to allow rotation about the sun gear 30.

[0018] Referring to Figs. 2A and 2B, the planet carrier 26 is held in place with a cap screw 58 that goes through a bearing 60 and a compression spring 62 and is threaded into a flanged nut 64 on the end of the engine drive shaft 22.

[0019] Referring again to Figs. 2A and 2B, a flange 66 is attached and sealed to the belt driver pulley 24 to form a pocket where a lubricant for the gearing 20 is contained.

[0020] As shown in Fig. 1, a wound spring clutch 68 is provided to assure that a load, such as the truck being pulled from the mud, attached to the cable 12 will remain safely held in position when the engine 16 is not driving the drum 14.

[0021] Fig. 1 also shows a spring-loaded freewheel knob 70 which when manually pulled out allows the drum 14 to freewheel so that the cable 12 can be manually paid out from the drum 14 in order, for example, to attach the cable 12 to a tree away from the mud and the truck on which the winch 10 has been mounted.

[0022] Finally, as shown in Fig. 1, the belt 18 is coupled to an input pulley 72 which drives the drum 14 through the wound spring clutch 68 and a series of planetary gears 74.

Claims

1. A portable winch comprising
   an internal combustion engine,
   a line feeding mechanism for paying out or drawing in a line, and
   controllable gearing for coupling said engine to drive said line feeding mechanism to selectively either pay out or draw in said line.

2. The winch of claim 1 wherein said controllable gearing includes a planetary gear train with an inner driving sun gear, an outer ring gear, and planet gears disposed between and engaging said inner driving gear and said outer ring gear.

3. The winch of claim 2 wherein said controllable gearing further comprises a mechanism for selectively either interlocking the motion of said driving sun gear with said outer ring gear, or
   permitting relative rotation of said driving sun gear and said outer ring gear in opposite directions.

4. The winch of claim 3 wherein said mechanism comprises shafts on which said planet gears are mounted, and said outer ring gear comprises bores for receiving said shafts, said shafts being movable axially from a position in which they are engaged in said bores and the motion of said driving sun gear is interlocked with said outer ring gear, to a position in which they are disengaged from said bores and relative rotation of the driving sun gear and the outer ring gear in opposite directions is permitted.

5. The winch of claim 2 wherein said ring gear has an outer driving surface, and further comprising
   a drive belt coupling the outer surface of the ring gear to a drive pulley.

6. The winch of claim 1 wherein said line feeding mechanism comprises a drum.

7. The winch of claim 1 wherein said engine comprises a non-reversing gasoline powered engine.

8. The winch of claim 4 further comprising a lever for moving said shafts between said positions.

9. The winch of claim 8 further comprising an omega-shaped spring for biasing said lever to move to either of two positions.

Drawing