JPH09132391A - Locking device for hydraulic garage jack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the natural fall of an arm even in the case of oil pressure in a hydraulic cylinder escaping by providing a locking gear fixedly at a shaft rotated by the elevating motion of the arm, and providing the body frame side with a lock pin in a state of being operated to be locked to and detached from the locking gear. SOLUTION: An arm 15 is moved up to the desired height, and in this position, an operating handle 27 is rotated clockwise. A transmission shaft 30 is rotated clockwise, and a transmission member 33 is moved in the direction of an arrow mark A, so that an operating rod 36 moves forward in the direction of the arrow mark A. With this forward movement, the tip face of the operating rod 36 comes in contact with the rear end face of a lock pin 38 to push it forward, and a locking claw 40 is fitted in and engaged with a root part of a locking gear 37. The rotation of the locking gear 38, that is, the downward rotary motion of the arm 15, is impeded. The arm 15 is not therefore rotated downward even if oil pressure in a hydrayulic cylinder 68 escapes due to the aged deterioration of valves in a hydraulic pump and a hydraulic circuit and that of seal packing of a hydraulic piston or the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lock device for a hydraulic garage jack, and more particularly to a lock device for locking an ascending position of an arm to prevent its descending.

[0002]

2. Description of the Related Art Conventionally, as a hydraulic garage jack, as shown in FIG. 5, a pump rod 4 is moved forward and backward through a link 3 by swinging a lifting handle 1 back and forth around a support shaft 2. It is known that the hydraulic pump 9 is actuated, the piston rod 6 of the hydraulic cylinder 5 is moved forward through the hydraulic circuit portion 9a, and the arm 8 is raised about the support shaft 7. When lowering the arm 8, the hydraulic pump 9 is moved by a lowering handle (not shown).
The relief valve is opened to release the hydraulic pressure in the hydraulic cylinder 5.

[0003]

In the hydraulic garage jack as described above, the condition in which the hydraulic pump 9 and the valve in the hydraulic circuit 9a deteriorate with the passage of time, or the hydraulic pressure in the hydraulic cylinder 5 is released due to other causes. Then, there is a problem that the vehicle body is placed on the arm 8 and the arm 8 is lifted up and stopped at a desired position, and then the hydraulic pressure in the hydraulic cylinder 5 is gradually released so that the vehicle body naturally descends together with the arm 8.

Therefore, an object of the present invention is to provide a locking device which prevents the arm from descending naturally even if the hydraulic pressure in the hydraulic cylinder 5 is released as described above.

[0005]

In order to solve the above-mentioned problems, the first invention according to claim 1 is to provide a gear for locking a shaft (14) which is rotated by a vertical movement of an arm (15). (37) is fixed, and the lock pin (38) is locked to the locking gear (37) on the body frame side,
It is characterized in that it is provided so as to be detachable, and further, operating means for operating locking and detaching of the lock pin (38) is provided at an appropriate position.

In the present invention, when the arm (15) is raised to a desired height and the position is locked, the operating means is operated to insert the lock pin (38) into the lock gear (37). Stop. As a result, the lock gear (3
The rotation of 7) is blocked and the spontaneous lowering of the arm (15) is mechanically locked. To release this locked state,
By operating the operating means, the lock pin (38) is removed from the lock gear (38).

A second invention according to claim 2 is the arm (1
A lock gear (37) is fixedly mounted on the shaft (14) which is rotated by the ascending / descending movement of (5), a lock pin (38) is provided on the body frame side, and a locking claw (40) of the lock pin (40) is used for the lock gear ( 37) so as to engage and disengage with respect to the lock pin (38), and the lock pin (38) is provided with a spring (45) for urging the lock pin (38) in the release direction.
1) is provided with an operating rod (36) which is formed separately from the lock pin (38) and which is arranged to face the lock pin (38) so that the lock pin (38) can be pushed in the locking direction. An operating handle (27) for moving the operating rod (36) forward and backward is provided on the body frame side.

In the present invention, when the arm (15) is raised to a desired height and the position is locked, the operating handle (27) is rotated in one direction to operate the operating rod (36).
Of the lock pin (38)
Is pushed forward against the spring 45 to lock the locking claw (40) to the locking gear (38). As a result, the rotation of the locking gear (37) is blocked, and the natural lowering of the arm (15) is mechanically locked. To release the locked state, the operation handle (27) is rotated in the opposite direction to retract the operation rod (36). As a result, the lock pin (38) is retracted by the urging force of the spring 45, and its locking claw (4
0) is disengaged from the lock gear (37) and the lock is released.

Further, when the arm (15) is in a raised state, its load is large, the rotational force of the lock gear (37) is large, and the frictional resistance of the lock pin (38) is increased by the spring (45). If it becomes bigger than the power,
At the time of the release operation as described above, first, only the operation rod (36) retracts. When the arm (15) is slightly moved upward by the lifting handle (21) and the lock gear (37) is rotated, the above-mentioned frictional resistance force of the lock pin (38) causes the above-mentioned spring (45) to move. When it becomes smaller than the urging force, the lock pin (38) is naturally released from the lock gear (37) by the urging force of the spring (45), and the lock is released. Therefore, even if the frictional resistance of the lock pin (38) is large as described above, regardless of this, the operating handle (2
7) Can be easily rotated.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of the present invention shown in FIGS. 1 to 4 will be described. Numerals 10 and 11 are container frames which can be conveyed by wheels 12 and 13. Reference numeral 14 denotes an arm rotation shaft, which is rotatably installed between the two body frames 10 and 11. Reference numeral 15 is an arm having a base fixed to the arm rotation shaft 14, and the arm 15 is rotated around the arm rotation shaft 14 in the left-right direction of FIG. A receiving tray 16 is provided at the tip of the arm 15, and the receiving tray 16 supports a vehicle body 17 to move up and down.

Reference numeral 18 denotes a hydraulic cylinder, the tip of a piston rod 19 of which is connected to a portion of the arm 15 extending below the arm rotation shaft 14. This connecting portion is similar to that shown in FIG. Therefore, when the piston rod 19 advances to the right in FIG.
Stands up and the arm 15 falls down when retreating to the left.

A hydraulic circuit section 2 is provided at the rear of the hydraulic cylinder 18.
0 is connected, and the hydraulic pump 20a is operated via the rod 23 by swinging the lifting handle 21 back and forth or depressing the foot petal 22 to supply the oil in the oil tank 24 into the hydraulic cylinder 18 via the hydraulic circuit unit 20. Then, the piston rod 19 is moved forward.

Reference numeral 25 denotes a descending handle, which is tilted rearward to move a rod 26 shown in FIG. 2 to operate a relief valve in the hydraulic circuit section 20, thereby causing the hydraulic cylinder 18 to move.
The hydraulic pressure inside is released to lower the arm 15.

Next, the locking means will be described. Reference numeral 27 denotes an operation handle, the shaft 28 of which is provided on the outer surface of the body frame 10 in a vertical state and rotatable in a plane. A bevel gear 29 is fixed to the shaft 28.

Reference numeral 30 denotes a transmission shaft horizontally and rotatably provided on the outer surface portion of the body frame 10. A bevel gear 31 meshing with the bevel gear 29 is fixed to the rear end thereof, and a male screw 32 is engraved on the front portion thereof. Has been done.

Reference numeral 33 denotes a transmission member, which is the body frame 10 described above.
Is provided so as to be movable in the front-rear direction by being inserted into a hole 34 formed in the outer peripheral surface of the female screw body 35. The forward / reverse rotation of the transmission shaft 30 moves the transmission member 33 in the front-rear direction to move the operating rod 36 forward and backward in the front-back direction, which is the arrow AB direction.

Reference numeral 37 denotes a lock gear, which is fixed to the arm rotating shaft 14 so as to rotate integrally therewith. Reference numeral 38 denotes a lock pin, which is provided in a guide tube 39 fixed to the inner surface of the body frame 10 so as to be slidable in the front-rear direction. The tip of the lock pin 38 has the lock gear 3
7 is formed in a pointed locking claw 40 that is fitted and engaged in the valley portion 37a of the No. 7 and the rear end surface 41 faces the front end surface 42 of the operation rod 36 so as to be able to come into contact with and separate from it. Reference numeral 43 is a guide bolt screwed to the guide cylinder 39, the inner end of which is fitted in an axial guide groove 44 formed in the lock pin 38, and the lock pin 38 is movable in the axial direction, but in the circumferential direction. I try not to rotate. 45 is a pin 46 fixed to the lock pin 38 and the guide tube 3
A tension spring that is provided by being locked to the end plate 47 of No. 9 is used to pull the lock pin 38 in the direction of always coming out from the locking gear 37, that is, to the left in FIG.

Next, the operation of the locking means in this embodiment will be described. First, in order to release the lock state shown in the drawing, the operation handle 27 is manually rotated, for example, in the opposite direction, and the transmission shaft 3 is rotated through both bevel gears 29 and 31.
0 rotates in the opposite direction, and its male screw 32 causes the female screw body 3
5 and the transmission member 33 integrated therewith move in the direction of arrow B in FIG. 2, and the operating rod 36 retracts in the direction of arrow B.

Then, the pulling load of the spring 45 causes the lock pin 38 to retreat following the operating rod 36, and the locking claw 4 thereof.
0 comes out from the lock gear 37. As a result, the arm 15 is lowered by operating the lowering lever 25.

If the vehicle body or the like mounted on the arm 15 is heavy and the rotational force acting on the locking gear 37 is large and the component force for pushing the lock pin 38 upward is large, the lock pin 38 is locked. The tooth portion of the gear 37 and the inner surface of the guide cylinder 39 are in strong contact with each other, and the sliding frictional resistance of the lock pin 38 increases. Therefore, in such a case, even if the operating rod 36 is retracted as described above, the lock pin 38
May not follow back. In such a case, after the operating rod 36 is retracted, the elevating handle 21 or the foot petal 22 is operated to slightly raise the arm 15. As a result, the locking gear 37 slightly rotates, the above-mentioned sliding frictional resistance of the lock pin 38 is loosened, and when the sliding frictional resistance force is weakened than the pulling force of the spring 45, the lock pin 38 is released. The pulling force of the spring 45 causes it to retract naturally, and the locking claw 40 is disengaged from the locking gear 37.

It is assumed that the operating rod 36 and the lock pin 38 described above are used.
When the and are integrally formed without being divided as described above, when the frictional resistance is large as described above, the lock pin 38 is directly connected to the lock gear 37 by the operation handle 27.
A large operating force is required to get it out of the lock, and the unlocking operation becomes extremely difficult.

However, by separating the operating rod 36 from the lock pin 38 and providing the spring 45 as described above, the operating rod 36 can be easily rotated regardless of the frictional resistance force as described above, and the lock can be locked. Release work becomes easy.

Next, the case of locking from the above released state will be described. Lifting handle 21 or foot petal 2
2 is operated to raise the arm 15 to a desired height, and the operation handle 27 is normally rotated at the raised position. As a result, the transmission shaft 30 rotates in the forward direction via both bevel gears 29, 31, and the male screw 32 moves the female screw body 25 and the transmission member 33 integrated with the female screw body 25 in the direction of arrow A in FIG. 36 advances in the direction of arrow A. Due to this forward movement, the front end surface 42 of the operation rod 36 is moved to the rear end surface 4 of the lock pin 38.
1 and pushes the lock pin 38 forward against the spring 45, and the locking claw 40 of the lock pin 38 pushes the trough 3 of the locking gear 37.
It engages with 7a. As a result, the rotation of the locking gear 38 is blocked, the downward rotation of the arm 15 is blocked, and the arm 15 is locked.

Therefore, the hydraulic cylinder 1 deteriorates with time, the valves in the hydraulic circuit deteriorate, the seal packing such as the hydraulic piston deteriorates, and other causes cause the hydraulic cylinder 1 to deteriorate.
Even if the hydraulic pressure in 8 is released, the arm 15 does not rotate downward.

[0025]

As described above, according to the first aspect of the invention, when the hydraulic pump or the valve in the hydraulic circuit deteriorates with age, or due to other reasons, the raised arm naturally descends. Even if this happens, by locking the lock pin to the lock gear, it is possible to prevent the arm from descending naturally. Further, such a locking mechanism can be manufactured extremely easily and inexpensively.

According to the second aspect of the present invention, further, even when a large load acts on the arm and a large sliding frictional resistance force is generated on the lock pin and it becomes difficult to release the lock pin, the releasing operation is performed. It can be done easily.

[Brief description of the drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a plan view of the main part.

FIG. 3 is a sectional view taken along line XX in FIG. 2;

FIG. 4 is a plan sectional view of a lock pin portion according to the present invention.

FIG. 5 is a side sectional view showing an arm lifting mechanism of a hydraulic garage jack to which the present invention is applied.

[Explanation of symbols]

10 ... Instrument frame 14 ... Arm rotation shaft 15 ... Arm 18 ... Hydraulic cylinder 27 ... Operation handle 30 ... Transmission shaft 33 ... Transmission member 36 ... Operation rod 37 ... Locking gear 38 ... Lock pin 41 ... Lock pin rear end surface

Claims (2)

[Claims] 1. A lock gear (37) is fixedly mounted on a shaft (14) which is rotated by an up-and-down movement of an arm (15), and a lock pin (38) is provided on the body frame side of the lock gear (37). A locking device for a hydraulic garage jack, characterized in that the locking pin (38) is provided with a locking / releasing function and an operating means for locking / unlocking the lock pin (38) is provided at an appropriate position. 2. A gear (37) for locking is fixedly mounted on a shaft (14) which is rotated by an up-and-down motion of an arm (15), and a lock pin (38) is provided on the body frame side, and a locking claw (4) thereof.
0) is capable of advancing and retreating so as to engage and disengage from the lock gear (37), and the lock pin (38) is provided with a spring (45) for urging the lock pin (38) in the disengagement direction. 38) A rear end surface (41) of the operation pin (36) which is formed separately from the lock pin (38) and is arranged to face the lock pin (38) in the locking direction.
A lock device for a hydraulic garage jack, characterized in that an operating handle (27) for moving the operating rod (36) forward and backward is provided on the body frame side.