JPH09165195A - Cylinder up-down type hydraulic jack with bottom load bearing part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To miniaturize a jack so as to reduce weight in a marked degree by fixing a ram to a jack base, forming a system of pushing up a cylinder with oil pressure, and providing a side load bearing part directly at the bottom of the cylinder. SOLUTION: A cylinder 2 integrally has a load bearing part 7 at the top part and a load bearing part 8 at the bottom part. Oil from an oil tank provided on a jack base 1 is pressurized by a manual pump 5, and the pressurized oil is fed to a clearance part between the cylinder head inner surface and a ram head part through a pressure withstanding oil hose. The cylinder 2 is thereby pushed up. When pressure is taken out of the pressurized oil in the cylinder 2, the pressurized oil is returned to the oil tank, and the cylinder 2 descends.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic jack with an upper and lower cylinder type claw capable of significantly reducing the weight of the entire jack.

[0002]

2. Description of the Related Art Conventionally, hydraulic jacks have been used to raise and lower heavy objects such as machines and plants for installation and transportation. However, since the conventional hydraulic jack itself has a certain height, it cannot be used when the clearance between these heavy objects and the floor surface is small, and in order to solve this problem, it has a claw. Jacks are used.

FIG. 5 shows a perspective view of a conventional hydraulic jack. On a jack base 1, a cylinder 2 having an oil tank 4 on its outer surface is fitted with a vertically movable ram 3, and pressurized oil pressurized by a manual hydraulic pump 5 is transferred to the bottom of the cylinder 2 and the ram 3. Gap with bottom edge (not shown)
Is supplied to the ram 3 to push it up, and the ram 3 is lowered by releasing the pressure.

When attaching a claw to this jack, the claw cover 6 composed of the head 7, the claw 8 and the connecting portion 9 is connected to the slide 10 provided on the surface of the oil tank 4. A mating groove (not shown) provided inside the portion 9 is fitted to form a jack with a claw. As a result, by covering the head of the ram 3 with the nail cover 6,
The jack will increase in weight accordingly. In addition, since the oil tank 4 is concentrically provided on the surface of the cylinder 2,
The center-to-center distance between the head 6 and the claw 8 also becomes long, which also increases the weight of the claw cover 6. Further, the slide 10 to which the claw cover provided on the surface of the oil tank 4 is attached also further increases the weight of the jack.

[0005]

As described above, the conventional hydraulic jack is made extremely robust to carry a heavy load. Therefore, the jack itself has a considerable weight, and by attaching the claw cover 6 to the jack, the weight of the jack itself is further increased, which hinders the carrying and installation of the jack and reduces the weight of the jack. Is required. Therefore, it is an object of the present invention to provide a hydraulic jack with a claw having a reduced weight.

[0006]

The above object can be achieved by the present invention described below. That is, the present invention comprises a jack base, a ram fixed to the jack base, a cylinder that hermetically surrounds the ram, and a cylinder that moves up and down around the ram as an axis, and a hydraulic pressure source. It has a load bearing part and a load bearing claw integrally on the bottom part, and supplies pressurized oil from a hydraulic source to the gap between the ram upper part and the cylinder top inner surface to raise and remove the cylinder. It is a hydraulic jack with a cylinder top-bottom type claw characterized in that the cylinder is lowered by pressing.

In the hydraulic jack of the present invention, the ram is fixed to the jack base, the cylinder is hydraulically pushed up, and the claw is directly provided on the cylinder so that the connecting portion between the claw and the head in the conventional claw cover can be connected. No longer needed
As a result, the jack can be made compact and a significant reduction in weight is achieved.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described more specifically with reference to the drawings showing an example of the present invention. FIG. 2 is a perspective view showing an entire hydraulic jack with a claw showing an example of the present invention. The hydraulic jack with claws in this example includes a jack base 1, a ram fixed to the jack base 1 (which is in the cylinder 2 and not shown), and hermetically surrounds the ram,
Further, it is composed of a cylinder 2 which moves up and down around the ram as an axis and a hydraulic power source 5. The cylinder 2 has a load carrying portion 7 at the top and a load carrying pawl 8 at the bottom. When the oil from the oil tank 4 provided on the jack base 1 is pressurized by the manual pump 5 and the pressurized oil is supplied to the gap between the cylinder head inner surface and the ram head through the pressure resistant hose 11, the cylinder 2 is pushed up. When the pressurized oil in the cylinder 2 is depressurized, the pressurized oil returns to the oil tank 4 and the cylinder 2 descends.

FIG. 1 is a partially cutaway sectional view of FIG. 2, showing the details of the jack of the present invention. In FIG. 1, the cylinder 2 is integrally formed with a load carrying portion 7 at its head and a load carrying pawl 8 at its lower portion. A ram 3 formed integrally with the jack base 1 encloses the ram 3 and an O-ring 12 and a backup ring 13 for keeping airtightness with the cylinder 2 and preventing oil leakage surround the ram. Then fixed to the ram 3,
Further, bearings 15, 16 for smoothing the vertical movement of the cylinder 2 and a snap pin 19 for fixing the bearing 15 are attached. These O-rings 1
2, the backup ring 13, the bearings 15 and 16, and the snap pin 19 are all fixed to the ram 3 so that the cylinder 2 can move up and down smoothly without oil leakage.

Below the cylinder 2, a bearing 17,
A snap pin 20 for fixing the bearing 18 and the bearing 18 is attached, and similarly, the cylinder 2 can be moved up and down smoothly without oil leakage. Cylinder 2
Is restricted by a limit pin 14 attached to the upper portion of the ram, and the cylinder is prevented from rising any further.

Oil from the oil tank (not shown) is sucked into the oil suction port 21.
Then, the pressure is increased by the manual hydraulic pump 5, and the pressure oil is supplied from the pressure oil outlet 22 to the pressure oil supply port 23 provided in the cylinder head 7 through the pressure resistant oil hose (not shown). The pressurizing oil has a gap 24 between the inner surface of the head 7 of the cylinder 2 and the head of the ram 24.
And pushes up the cylinder 2 as shown in FIG. On the other hand, by the pressure relief valve 25 shown in FIG. 4 which is a front view,
By depressurizing the pressurized oil in the cylinder 2, the oil is returned to the oil tank 4, and the cylinder 2 descends.

As described above, the jack with a claw of the present invention has the same performance as the conventional jack with a claw,
Since the cylinder 2, the head portion 7 and the claw 8 are integrally formed, the connecting portion 9 and the slide 10 in the above-mentioned conventional claw cover 6 are unnecessary, and as a result, the weight of the jack is significantly increased. Mitigation is achieved. Further, by providing the oil tank 4 on the jack base without providing it on the surface of the cylinder 2 as shown in FIG. 5, the center-center distance between the head and the claw of the cylinder is shortened, which also reduces the weight. Contribute to.

The above example is an example in which the cylinder is pushed up by the manual hydraulic pump installed on the jack base. However, both with and without the hydraulic pump installed in the jack (in this case, no oil tank is installed). The pressurizing oil supply port 23 at the head of the cylinder may be a one-touch type coupler, and one or more hydraulic jacks of the present invention may be connected to another manual or electric hydraulic pump to operate. Further, if a tuned hydraulic pump is used, it is possible to simultaneously operate a plurality of jacks.

The above example is an example in which the cylinder body, the head and the claws are integrally formed by casting the ram and the jack base, respectively, but each of the above is manufactured separately and welded, screwed, etc. The jack may be joined and integrated by a method that does not deteriorate the performance of the jack. Further, in order to supply the pressurized oil to the gap between the inner surface of the top of the cylinder 2 and the top of the ram 3, the pressure oil supply port 23 as described above is not provided in the cylinder head and the pressure hose 11 as described above is provided.
1 to form a pressurized oil flow path in the jack base and the ram 3 so that pressurized oil can be supplied to and discharged from the top of the ram 3 into the gap 24, as shown by the alternate long and short dash line in FIG. You can also do it.

As shown in FIGS. 1 and 2, the jack base 1 is provided with a guide shaft 26 so that the cylinder 2 does not excessively rotate in the horizontal direction when the cylinder 2 moves up and down by hydraulic pressure. Guide hole 27 in cylinder 2
Is preferably provided. The control mechanism of such a cylinder is an example, and is not limited to the illustrated example.
In FIG. 2, one corner of the oil tank 4 serves as a guide, and on the other hand, any control mechanism can be used as long as the cylinder does not excessively rotate in the horizontal direction when the cylinder is moved up and down, such as by providing a guide groove in the cylinder. Good.

[0016]

As described above, according to the present invention, a hydraulic jack with a claw having a significantly reduced weight is provided. As a result of the reduced weight of the jack, it is easier to carry and install, and the labor is also reduced.

[0017]

[Brief description of the drawings]

FIG. 1 is a partially cutaway sectional view of FIG.

FIG. 2 is a perspective view showing an example of a hydraulic jack with a claw of the present invention.

FIG. 3 is a diagram showing a state in which a cylinder is raised in FIG.

FIG. 4 is a front view of a hydraulic jack with a claw.

FIG. 5 is a view showing a conventional hydraulic jack and a cover with pawls.

[Explanation of symbols]

 1: Jack base 2: Cylinder 3: Ram 4: Oil tank 5: Manual hydraulic pump 6: Claw cover 7: Head 8: Claw 9: Connection between head and claw 10: Slide 11: Oil pressure hose 12: O -Ring 13: Backup ring 14: Limit pin 15-18: Bearing 19, 20: Snap pin 21: Oil suction port 22: Pressurized oil outlet 23: Pressurized oil supply port 24: Ram head and cylinder head inner surface Gap 25: Pressure relief valve 26: Guide shaft 27: Guide hole

Claims (1)

[Claims] 1. A jack base, a ram fixed to the jack base, a cylinder that hermetically surrounds the ram, and a cylinder that moves up and down about the ram, and a hydraulic pressure source. The cylinder has a load on its top. It has a supporting part and a weighted supporting claw integrally on the bottom part, and supplies pressurized oil from a hydraulic source to the gap between the ram upper part and the cylinder top inner surface to raise and depressurize the cylinder. Cylinder up and down type hydraulic jack with claw, characterized by lowering the cylinder.