JP3031194U - Jack safety device - Google Patents

Abstract

(57) [Summary] (Modified) [Objective] To provide a jack safety device having a simple structure, low cost, and high safety and good operability. A jack is a main body 10, a support mechanism 20 having at least a swingable lift arm 21, and a lift mechanism 30 for driving the support mechanism 20 to lift a support.
It consists of and. Further, a swingable safety hook 40 connected by a pivot is provided on the lift arm 21, and a safety hook 4 is provided.
The axis of 0 and the axis of rotation of the lift arm 21 are eccentric, and are configured so that when the support mechanism 20 moves up, it moves forward, and when it descends, it moves backwards.
A tooth profile that meshes with some hook teeth is provided in the portion where the hook receiving portion 50 and the hook teeth contact each other, and after some tooth shapes mesh with the hook teeth, the safety hook 40 may be retracted with a restriction. It is configured so that it cannot.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety device for a jack, and more particularly to a safety device for a jack that can prevent an accident due to a sudden lowering of the jack support mechanism when the jack lift mechanism fails.

[0002]

[Prior art]

 Conventional hydraulic jacks function as a lift mechanism by operating hydraulic cylinders. However, if the hydraulic cylinder were damaged or the oil leaked out, the supporting force of the jack immediately disappeared and dropped rapidly, which could cause the support to fall and cause an unexpected accident. is there.

Further, a general small hydraulic jack is limited in space and mechanism, and there is still no practical safety device. In other words, no security is provided when using the jack.

[0004]

[Problems to be solved by the device]

 An object of the present invention is to provide a jack safety device having a simple structure, low cost, high safety and convenient operation.

[0005]

[Means for Solving the Problems]

 The present invention has been proposed to achieve the above-mentioned object. A safety hook is pivotally connected to a lift arm or a link of a support mechanism of the jack so that it can be swung, and the support mechanism is raised or lowered. Accordingly, the safety hook is interlocked to cause forward and backward reciprocating movements, and thus, when moving forward, the hook teeth of the safety hook can mesh with some tooth shapes of the hook receiving portion. As a result, the support mechanism is constrained and cannot descend, and the purpose of safety protection can be achieved. Further, there is an actuating lever, and by operating this, the hook teeth of the safety hook can be disengaged from the tooth profile of the hook receiving portion. Thus, the support mechanism provides a safety device that can be lowered.

[0006]

【Example】

 Hereinafter, one embodiment of the present invention will be described in detail with reference to FIGS. In this embodiment, a horizontal jack for repair and maintenance of a general automobile will be described. The device of the present invention described in this embodiment is not limited to the various jacks presented in this embodiment, and the safety device of the present invention may be used for a jack having a swingable left arm or link. it can.

As shown in FIGS. 1 and 2, the jack of the present invention includes a main body 10 and a support mechanism 20. The support mechanism 20 has a lift arm 21 which is swingable up and down and is pivotally mounted on the main body 10. A support portion 22 is provided at the top end of the lift arm 21 to support a support. Is configured as follows. Further, there is a lift mechanism 30, which drives the above-mentioned lift arm 21 and swings upward to lift the supporting portion 22 at the end and push up the supporting object.

The safety device of the present invention includes a safety hook 40 pivotally mounted to the lift arm 21 and a hook receiving portion 50 with which the safety hook 40 engages. When the lift arm 21 is lifted, the safety hook 40 can be interlocked with and engaged with the hook receiving portion 50. After the safety hook 40 engages with the hook receiving portion 50, the safety hook 40 is restricted and cannot retract. Furthermore, the safety hook 40 and the hook receiving portion 50 cannot be separated unless the safety hook 40 is operated by the operator, and thus the lift arm 21 can be continuously maintained in the lifted state. Therefore, even if the lift mechanism fails, it does not suddenly descend and the purpose of safety protection can be achieved.

As shown in FIG. 3, the safety hook 40 has two lever arms 41 parallel to each other, one end of which is connected to the lift arm 21 by a pin 42 and the other end of which is connected to the other end. It has hook teeth 43. As shown in FIGS. 4 to 6, there is a step distance between the pin 42 and the fixed shaft 23 that fixes the lift arm 21. Therefore, the lift arm 21 moves upward with the fixed shaft 23 as the center. When rotating and rocking, the safety hook 40 is urged forward. In this embodiment, the pin 42 fixing the lever arm 41 is a pin connecting the lift arm 21 in the front lift mechanism 30. Therefore, the lift arm 21 can attach the safety hook 40 to the lift arm 21 without any modification.

The hook teeth 43 at the front end of the safety hook are reverse hook teeth that are inclined rearward, and the hook receiving portion 50 has a row of teeth 51 that can mesh with the row of the hook teeth 43. There is. Since the hook teeth 43 of the safety hook 40 are inclined rearward and the lever arm 41 can swing, the safety hook 40 is recommended forward by the lift arm 21. At this time, the hook teeth 43 are lifted by the tooth row 51 of the hook receiving portion 50, and slide over the upper ends of the slight tooth rows 51. However, when the safety hook 40 moves backward, the safety hook 40 automatically falls due to the weight, the hook teeth 43 and the tooth row 51 mesh with each other, and the safety hook 40 cannot move backward. Therefore, the lift arm 21 is restricted and cannot descend.

The above-mentioned tooth row 51 of the hook receiving portion 50 is arranged within the range of its movement along the direction of the reciprocating movement of the safety hook 40, and thus within the lift angle range of the lift arm 21. All the claw teeth 43 can mesh with the tooth row 51. Thus, it is safe for the jack to lift the support at any altitude.

In order to ensure that the above-described safety hook 40 and the hook receiving portion 50 mesh with each other, it is preferable that the safety hook 40 is installed at a position higher than the hook receiving portion 50. . Then, the weight of the safety hook 40 is utilized to automatically engage with the hook receiving portion 50. Besides this, a spring can be added to the safety hook 40. The safety hook 40 and the hook receiving portion 50 are engaged with each other by utilizing the elasticity of the spring. In that case, the safety hook 40 does not necessarily have to be installed above the hook receiving portion 50, and can be installed at any position.

The operation method of the above-mentioned jack is almost the same as that of a general jack, and the only difference is that when the jack descends the lift arm and lowers the supporting object, the safety hook 40 is always put in the hook receiving portion first. Must be detached from 50. According to the present invention, an operating lever 60 is separately installed on the jack so that the operator can perform the above operation safely and conveniently. As shown in FIG. 7, the operating lever 60 is attached to the main body 10 by using a pin 61, passing through the middle portion thereof. At the front end of the operating lever 60, there is an operating plate 62 which can be brought into contact with the lever arm 41, and the end of the operating plate 62 extends to the end of the main body 10 so that it can be easily contacted by an operator. Has been. The operator pushes the end of the actuating lever 60 downward to raise the front end of the actuating lever 60, and thus the actuating plate 62 is actuated to lift the safety hook 40, and the safety hook 40 is lifted by the hook receiving portion. It is detached from 50.

Besides, in order to allow the safety hook 40 to be smoothly detached from the hook receiving portion 50, the hook receiving portion 50 is mounted on the front wheel shaft 11 of the main body 10 in a swingable manner. . When the safety hook 40 is detached from the hook receiving portion 50, if the hook teeth 43 interfere with the tooth row 51, the hook receiving portion 50 is swung upward by the safety hook 40 and Since the claw teeth 43 can be swung at an angle at which they can be detached from the tooth row 51, it is possible to avoid the phenomenon that cannot be detached.

The safety device of the present invention prevents the lift arm 21 from descending by using the safety hook 40 and the hook receiving portion 50 when the lift mechanism 30 is broken during use of the jack. You can Furthermore, since it is possible to support the support without using a separate auxiliary support component, it is possible to prevent the risk of accidental fall of the support and improve the convenience of use. it can. Further, when the pressure is applied after the safety hook 40 of this kind and the hook receiving portion 50 are engaged with each other, both are automatically aligned with each other, and the engagement therebetween can be firmly secured.

Further, according to the present invention, the above-described safety hook 40 and the hook receiving portion 50 can be evenly mounted in the space inside the main body 10 by using an existing jack structure. For this reason, there is no need to care for the structure of the jack, it can be installed very easily, and it can contribute to cost reduction.

[0017]

[Effect of device]

 The jack safety device of the present invention can prevent the lifting of the lift arm when a failure occurs in the lifting mechanism of the jack, and prevent the risk of the support dropping due to a sudden lowering. Since it can be used for a jack, the cost is low, and the operation is simple, so that it is a device having a truly remarkable effect.

[Brief description of drawings]

FIG. 1 is a three-dimensional view of the jack of the present invention.

FIG. 2 is a partially cutaway side view of the jack of the present invention.

FIG. 3 is a partially enlarged three-dimensional view of the safety device of the present invention.

FIG. 4 is a partially cutaway side view showing an operating state of the safety device of the present invention.

FIG. 5 is a partially cutaway side view showing an operating state of the safety device of the present invention.

FIG. 6 is a partially cutaway side view showing an operating state of the safety device of the present invention.

FIG. 7 is a partially cutaway side view showing the operation of the operating lever used in the present invention.

[Explanation of symbols]

 10 main body 11 front wheel shaft 20 support mechanism 21 lift arm 22 support portion 23 fixed shaft 30 lift mechanism 40 safety hook 41 lever arm 42 pin 43 hook tooth 50 hook receiving portion 51 tooth row 60 operating lever 61 pin 62 operating plate

Claims (5)

[Scope of utility model registration request] 1. A safety device for a jack, wherein the jack has a main body, a support mechanism including at least a swingable lift arm or a link, and a lift mechanism for driving the support mechanism to lift a support. Further, the safety device has a swingable safety hook pivotally connected to the lift arm or link, and the pivot center of the safety hook and the rotation of the lift arm or link. The shaft center is eccentric so that when the support mechanism moves up, the shaft center moves forward, and when the support mechanism descends, the shaft center moves in the same manner and moves backward. Has a hook tooth that is inclined rearward, the hook receiving portion is installed on the main body at a position where it can contact the safety hook, and the hook tooth of the safety hook reciprocates along with the safety hook. So that it can come into contact with the hook receiving part when Further, a tooth profile that meshes with the hook teeth is provided in a portion where the hook receiving portion and the hook teeth are in contact with each other, and thus after the tooth profile and the hook teeth are meshed with each other. , The safety hook is configured so that it cannot be retracted due to a limitation, and when the support mechanism is lifted by the combination of the respective devices, the safety hook is interlocked to move forward, so that the hook receiving portion of the hook is received. It is configured so that it meshes with the tooth profile and thus the safety hook cannot retract and thus the support mechanism cannot descend, and when the lift mechanism fails, the support mechanism lowers suddenly. A safety device for a jack, characterized in that it is configured so as to prevent the risk of being damaged. 2. The safety device has an actuating lever,
It is installed on the body by a pivot, one end of which extends to the outside of the body to be used by an operator, and the other end of which acts on the safety hook to detach the safety hook from the hook receiving portion. The safety device for a jack according to claim 1, wherein the safety device is configured to perform the action. 3. The hook receiving portion of the safety device is attached to the main body by a pivot so as to prevent interference when the safety hook and the hook receiving portion are detached from each other. The safety device for a jack according to claim 1. 4. The jack safety device according to claim 1, wherein the safety hook of the safety device is configured so as to be able to hold the engagement with the hook receiving portion by its own weight. 5. The safety device for a jack according to claim 1, wherein the safety hook of the safety device for the jack is configured so as to be able to hold the engagement with the hook receiving portion by the elastic force of the spring. .