Patent Application
20210053806
The present invention is related to a winch, and particularly to an overload protection mechanism for the winch.
A winch is a mechanical device that uses the rotation of the spool to wind or release ropes, such as, steel ropes. After the winding of the cable is completed, if the power source continues to output power to the transmission shaft installed in the spool, the transmission shaft is likely to be damaged. In order to avoid this situation, an overload protection mechanism is usually set inside the winch to protect the transmission shaft, so that the transmission shaft can release the power transmission with the power source when the load is too large.
The prior art teaches that the overload protection mechanism, as disclosed in the Republic of China (Taiwan) Patent No. 1622549, mainly relies on the combination of the rolling element and the inner and outer arc grooves to release the power transmission between the input transmission shaft and the transmission ring in the case of excessive load, so that the input transmission shaft cannot transmit power to the output transmission shaft in order to protect the overall structure. This structure, however, can still be improved.
One of the purposes of the present invention is to provide an overload protection mechanism for a winch, which has a good overload protection.
In order to achieve such benefit, the overload protection mechanism of the present invention includes an input transmission shaft, an output transmission shaft, and a clutch mechanism. The input transmission shaft and the output transmission shaft coaxially correspond to each other, the input transmission shaft has an input end and a first transmission end, and the output transmission shaft has a second transmission end and an output end. The clutch mechanism has a first clutch member, a second clutch member and an elastic part. The first clutch member is set at the first transmission end of the input transmission shaft, so that the first clutch member can operate synchronously with the input transmission shaft. The second clutch member is set at the second transmission end of the output transmission shaft, so that the second clutch member can operate synchronously with the output transmission shaft. In addition, the first clutch member has a first engaged part, and the second clutch member has a second engaged part. The first engaged part of the first clutch member is detachably engaged in the second engaged part of the second clutch member, and the elastic part acts on the first clutch member to push the first clutch member in the direction of the second clutch member.
In view of such structure, under the condition that the output end of the output transmission shaft is under normal load, the first engaged part of the first clutch member and the second engaged part of the second clutch member are engaged with each other, so that the input transmission shaft can transmit power to the output transmission shaft through the clutch mechanism, and the output transmission shaft can rotate smoothly. Once the output end of the output transmission shaft is overloaded, the first engaged part of the first clutch member and the second engaged part of the second clutch member will be disengaged which cuts off the power transmission between the input transmission shaft and the output transmission shaft, so that the input transmission shaft cannot transmit power to the output transmission shaft, thereby protecting the overall structure.
Preferably, the first engaged part of the first clutch member is one of recesses or bumps. At least one of the first engaged parts is a bump that has two first inclined planes which are inclined in opposite directions and one first plane which connects the two first inclined planes. The second engaged part of the second clutch member is the other one of the recesses or bumps that matches the corresponding recess or bump of the first engaged part. For example, the second engaged part can include a recess that has two second inclined planes which are inclined in opposite directions and one second plane which connects the two second inclined planes. Therefore, when the first engaged part of the first clutch member is engaged with the second engaged part of the second clutch member, the first inclined plane of the first engaged part abuts on the second inclined plane of the second engaged part, and the first plane of the first engaged part abuts on the second plane of the second engaged part. When the output end of the output transmission shaft is overloaded, with the cooperation of the first inclined plane and the second inclined plane, the first engaged part of the first clutch member engaged with the second engaged part of the second clutch member can be quickly and surely disengaged.
Preferably, the outer surface of the first transmission end of the input transmission shaft has an insertion portion. The first clutch member has the first shaft hole. The first clutch member is sleeved on the first transmission end of the input transmission shaft with the first shaft hole. In addition, the wall of the first shaft hole has an insertion slot. The input transmission shaft is engaged in the insertion slot of the first clutch member with the insertion portion of the first transmission end, so that the input transmission shaft is able to drive the first clutch member to rotate them together.
Preferably, the first transmission end of the input transmission shaft has a screw hole and the clutch mechanism also has a screw. The screw passes through a washer and is screwed in the screw hole, so that the washer abuts against the first transmission end of the first clutch member and the input transmission shaft to prevent the first clutch member from falling off.
Preferably, the one side of the first clutch member opposite to the second clutch member has a shaft and a container surrounding the shaft. The elastic part is sleeved, e.g., is set on, the input transmission shaft. The outer circumferential surface of the input transmission shaft has a shoulder between the input end and the first transmission shaft. The clutch mechanism also has a support ring. One side of the support ring abuts the shoulder of the input transmission shaft. The other opposite side of the support ring receives one end of the elastic part. The other end of the elastic part is sleeved on the shaft of the first clutch member and located in the container of the first clutch member, and abuts on the one side of the first clutch member facing the second clutch member, so that the elastic part is able to provide elastic force, e.g., spring force, to push the first clutch member toward the second clutch member.
Preferably, the second clutch member has a second shaft hole. The second clutch member is sleeved on the second transmission end of the output transmission shaft with the second shaft hole. The wall of the second shaft hole has a second section intersection. The outer circumferential surface of the second transmission end of the output transmission shaft has a first section intersection, so that the first and the second section intersections are able to abut each other, so that the second clutch member can rotate with the output transmission shaft.
Preferably, the second transmission end of the output transmission shaft has a locking ring slot and a locking ring is provided in the locking ring slot. The locking ring abuts against one side of the second clutch member facing the first clutch member to prevent the second clutch member from falling off.
Preferably, the shape of the input end of the input transmission shaft is hexagonal in order to connect with the chuck so that the input transmission shaft can be driven to be rotated by the electric tool with the aforementioned chuck.
The detailed structure, features, assembly or use of the overload protection mechanism for the winch provided by the present invention will be described in the detailed description of the following embodiments. However, those with ordinary knowledge in the field of the present invention should be able to understand that the detailed description and the specific embodiments listed in the implementation of the present invention are only for describing the present invention, and do not limit the scope of claims of the present invention.
In the specification, including the following embodiments and claims, nouns involving directionality are based on the direction as shown in the figures. In the following embodiments and drawings, the same element numbers represent the same or similar elements or structural features.
As shown in
As seen in
The input transmission shaft 20 is rotatably arranged on the spool 14 and has an input end 21 and a first transmission end 22. The input end 21 is located outside the spool 14, and the input end 21 has a shape that is able to connect with the chuck (not shown in the figure) of an electric tool, e.g., having a hexagonal shape, and is configured so that the input transmission shaft 20 is able to be driven by the electric tool, e.g., to rotate. The first transmission end 22 is located in the spool 14. The outer circumferential surface of the first transmission end 22 has a plurality of elongated insertion portions 23 arranged in an equally spaced ring shape, and the first transmission end 22 has a screw hole 24 extending along its axial direction. In addition, the outer circumferential surface of the input transmission shaft 20 also has a shoulder 25 between the input end 21 and the first transmission end 22.
The output transmission shaft 30 is rotatably arranged on the spool 14 and is located on the same axis as the input transmission shaft 20. The output transmission shaft 30 has an output end 31 and a second transmission end 32. The output end 31 is located outside the spool 14 and is connected to the reduction-gear set 16 (as shown in
The clutch mechanism 40 has a first clutch member 50, a second clutch member 60 and an elastic part 68.
The first clutch member 50 has a first shaft hole 51 that penetrates the opposite sides of left and right sides of the first clutch member 50. The wall of the first shaft hole 51 has a plurality of elongated insertion slots 52 arranged in an equally spaced ring shape. The first clutch member 50 uses the first shaft hole 51 to be sleeved on the first transmission end 22 of the input transmission shaft 20, and then uses the insertion slots 52 to be embedded on the insertion portions 23 of the first transmission end 22 of the input transmission shaft 20, so that the first clutch member 50 is driven by the input transmission shaft 20 so that they rotate together. In addition, a screw 58 passes through a washer 59 and is locked in the screw hole 24 of the first transmission end 22 of the input transmission shaft 20, so that the washer 59 abuts against the right side of the first clutch member 50 and the end surface of the first transmission end 22 of the input transmission shaft 20 to prevent the first clutch member 50 from detaching from the first transmission end 22 of the input transmission shaft 20.
The second clutch member 60 has a second shaft hole 61 that penetrates the two opposite sides of the left and right sides of the second clutch member 60. The wall of the second shaft hole 61 has a second section intersection 62. The second clutch member 60 uses the second shaft hole 61 to be sleeved on the second transmission end 32 of the output transmission shaft 30, where its right side abuts against a thrust bearing 66 provided on the output transmission shaft 30, and then uses the second section intersection 62 to abut the first section intersection 33 of the second transmission end 32 of the output transmission shaft 30, so that the second clutch member 60 drives the output transmission shaft 30 so that they rotate together. In addition, a locking ring 67 is buckled into the locking ring slot 34 of the second transmission end 32 of the output transmission shaft 30 and abuts against the left side of the second clutch member 60 to prevent the second clutch member 60 from detaching from the second transmission end 32 of the output transmission shaft 30. As shown in
The elastic part 68, e.g., a compression spring here, is sleeved on the input transmission shaft 20. As shown in
It can be seen from the above that when the input transmission shaft 20 is driven by the electric tool, the first clutch member 50 rotate together with the input transmission shaft 20. As seen in
When the rope is wound up, the output transmission shaft 30 will stop rotating with the spool 14 along with the second clutch member 60. If the electric tool continues to output power to the input transmission shaft 20 at this time, the input transmission shaft 20 will also drive the first clutch member 50 to rotate. However, if the first clutch member 50 starts to rotate, since the second clutch member 60 remains stationary, through the cooperation, e.g., engagement, of the first inclined plane 56 and the second inclined plane 64, on the one hand, the first clutch member 50 moves along the axial direction of the input transmission shaft 20 away from the second clutch member 60, which compresses the elastic part 68 to accumulate the elastic force of the elastic part 68, e.g., recovery power. On the other hand, the first clutch member 50 also rotates relative to the second clutch member 60, so that the first engaged part 55 of the first clutch member 50 gradually separates from the second engaged part 63 of the second clutch member 60. While the two are completely separated, the power transmission between the input transmission shaft 20 and the output transmission shaft 30 is cut off.
In summary, in terms of the present invention's overload protection mechanism 18 for a winch 10, under the condition that the output end 31 of the output transmission shaft 30 is under normal load, the first engaged part 55 of the first clutch member 50 and the second engaged part 63 of the second clutch member 60 are engaged with each other, so that the input transmission shaft 20 can transmit power to the output transmission shaft 30 through the clutch mechanism 40, so that the output transmission shaft 30 can rotate smoothly. Once the output end 31 of the output transmission shaft 30 is overloaded, the first engaged part 55 of the first clutch member 50 and the second engaged part 63 of the second clutch member 60 will be disengaged to cut off the power transmission between the input transmission shaft 20 and the output transmission shaft 30, so that the input transmission shaft 20 cannot transmit power to the output transmission shaft 30, and the overall structure is protected.
| Number | Date | Country | Kind |
|---|---|---|---|
| 108129864 | Aug 2019 | TW | national |
