JPH0623761Y2 - Mounting device for hydraulic unit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a hydraulic cylinder used in a hydraulic lift device, and to a mounting device for a hydraulic unit that supplies hydraulic pressure to the hydraulic cylinder.

[Prior Art] Usually, the hydraulic cylinder and the hydraulic unit are connected via a pipe line, but due to the limited installation space, the hydraulic cylinder and the hydraulic unit can be combined together in a small space. As a device that can be installed in, for example, a hydraulic unit mounting device shown in FIG. 3 has been developed.

This is composed of a hydraulic cylinder 1 and a hydraulic unit 2, and the hydraulic unit 2 is connected to a mounting portion 4 of a cylinder bottom 3 via bolts 5 and 6.

The hydraulic cylinder 1 has a piston 11 inside an inner cylinder 7.
The piston rod 9 is movably inserted through the inner cylinder 7, three oil chambers 16, 17, 18 are defined in the inner cylinder 7, and the free piston 10 is movably inserted in the oil chambers 17, 18. There is.

Bracket 1 for cylinder bottom 3 and piston rod 9
2 and 13 are provided and mounted, for example, between the main body of the hydraulic lift device and the working machine.

The cylinder bottom 3 has an oil hole 1 communicating with the oil chambers 16 and 17.
4, 15 are provided, and the oil holes 14, 15 are selectively connected to the hydraulic pump 19 or the hydraulic tank 20 of the hydraulic unit 2.

The hydraulic unit 2 is composed of a hydraulic pump 19, a hydraulic tank 20, a switching valve 21, and an electric motor 22 which are integrally assembled.

[Problems to be Solved by the Invention] In the above-described conventional hydraulic unit mounting device, the hydraulic unit 2 is coupled to the mounting portion 4 of the cylinder bottom 3,
Moreover, since the two oil holes 14 and 15 are formed in the cylinder bottom 3, it is necessary to make the mounting portion 4 large. For this reason, the cylinder bottom 3 becomes long, the basic length of the hydraulic cylinder 1 becomes long accordingly, the mounting space is restricted, the weight becomes heavy, and the material cost increases.

Therefore, the purpose of the present invention is to shorten the basic length of the hydraulic cylinder, reduce the weight, save the material cost, and change the mounting position of the hydraulic unit in the axial direction of the inner cylinder according to the customer's specifications. An object of the present invention is to provide a mounting device for a hydraulic unit that is possible and has flexibility in mounting.

[Means for Solving the Problems] In order to achieve the above object, the structure of the present invention has a double inner cylinder and outer tube, and a passage is formed between the inner cylinder and the outer tube. In the mounting device of the hydraulic unit in which the hydraulic cylinder is connected to the hydraulic cylinder via the bracket, the bracket is composed of the hydraulic cylinder, the hydraulic unit, the hydraulic pump, the hydraulic tank, and the switching valve. The outer tube is composed of a cylindrical portion fitted to the outer periphery of the inner cylinder and a mounting portion integrally formed with the cylindrical portion.The outer tube extends axially outside the inner cylinder while sandwiching the cylindrical portion of the bracket from both sides. Two of them are arranged in series, a hydraulic unit is connected to the outer end of the mounting part, and two oil passages are formed in the cylindrical part and the mounting part. This oil passage opens in two passages formed between the hydraulic cylinder and the outer cylinder, and is selectively connected to a hydraulic pump or a hydraulic tank via a switching valve. It is a thing.

[Operation] The passage of the hydraulic cylinder is selectively connected to the hydraulic pump or the hydraulic tank via the oil passage of the bracket to perform expansion / contraction operation.

Since the bracket fits on the outer circumference of the inner tube on the hydraulic cylinder side and is inserted between the two outer tubes, it is necessary to adjust the length of the two outer cylinders and the fitting position of the bracket on the outer circumference of the inner cylinder. For example, the hydraulic unit can be mounted at an intermediate or arbitrary position within the length range of the inner cylinder, and it is not necessary to purposely lengthen the hydraulic cylinder to mount the hydraulic unit.

Since the cylindrical portion forming the bracket is fitted to the outer circumference of the inner cylinder, the bracket can be moved in the rotational direction to adjust the mounting position of the hydraulic unit.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 and 2.

The hydraulic unit 2 is configured by integrally forming a hydraulic pump 19, a hydraulic tank 20, a switching valve 21, and an electric motor 22. The hydraulic unit 2 is mounted in the middle of the hydraulic cylinder 1 via a bracket 23. .

In the hydraulic cylinder 1, a piston rod 9 is movably inserted into an inner cylinder 7 via a piston 11, and a cylinder bottom 3a and a bearing 24 are connected to both sides of the inner cylinder 7. Brackets 12 and 13 are provided on the cylinder bottom 3a and the piston rod 9, respectively, and are connected to a hydraulic lift device or the like.

Two oil chambers 16 and 18 are defined in the inner cylinder 7 by a piston 11, and a free piston 10 is slidably inserted in the inner cylinder 7 so that the free piston 10 and the cylinder bottom 3a are connected to each other. The chamber 17 is partitioned.

An extension port 25 and a pressure port 26 that connect the two oil chambers 16 and 18 to each other are formed in the piston 11, and a valve 27 for generating an extension side damping force is provided at the lower mouth end of the extension port 25 so as to be openable and closable. A pressure valve or a check valve 28 is openably and closably provided at the upper end of the port 26.

The bracket 23 is composed of a cylindrical portion 23a fitted to the outer periphery of the inner cylinder 7 and a mounting portion 23b integrally formed with the cylindrical portion 23a.

A cylindrical portion 23a of the bracket 23 is fitted on the outer circumference of the inner cylinder 7, and an outer tube 8a coupled to the cylinder bottom 3a is provided on one side of the cylindrical portion 23a.
The outer tube 8b obtained by crimping the bearing 24 and the seal member 29 is connected to the other side. Therefore, the bracket 23 is narrowly provided on both sides between the outer tubes 8a and 8b and is fixed in the axial direction.

Therefore, by appropriately selecting the lengths of the outer tubes 8a and 8b, the position of the bracket 23, that is, the mounting position of the hydraulic unit 2 can be changed in the axial direction of the inner cylinder 7. For example, the hydraulic cylinder 1 is mounted on the device. In the event that the hydraulic unit 2 interferes, the mounting position of the hydraulic unit 2 can be changed to avoid the interference.
The mounting position of can be changed, and there is flexibility in mounting.

Further, the cylindrical portion 23a can be rotated to an arbitrary position in the rotational direction with respect to the outer circumference of the inner cylinder 7, and thus the hydraulic unit can be moved in the rotational direction.

Two independent oil passages 30 and 31 are provided between the inner cylinder 7 and the outer tubes 8a and 8b. One oil passage 30 communicates with the oil chamber 17 through an oil hole 32 provided in the cylinder bottom 3a. The other oil passage 31 communicates with the oil chamber 16 via an oil hole 33 provided in the bearing 24.

The bracket 23 is connected to the hydraulic unit 2 at the outer end of the mounting portion 23b via a bolt 24 and a flange portion 23c.

Oil passages 34 and 35 that open to the passages 30 and 31 are formed in the attachment portion 23b and the cylindrical portion 23a.
Reference numerals 4 and 35 designate the hydraulic pump 19 selectively via the switching valve 21.
Alternatively, it is connected to the hydraulic tank 20.

In the extension operation of the hydraulic cylinder 1, the oil passage 24 is connected to the hydraulic pump 19, and the other oil passage 35 is connected to the hydraulic tank 20. At this time, the oil chamber 17 has a high pressure, and the other oil chamber 1
6 becomes a low pressure, the piston rod 9 extends, and the working machine is raised.

When the high pressure oil is introduced into the oil chamber 16 during the compression operation and the oil in the oil chamber 17 is returned to the hydraulic tank 20, the piston rod 9 descends.

When the piston rod 9 is held at an arbitrary position, the piston rod 9 may be extended to a predetermined position and the switching valve 21 may block the oil passages 34 and 35 to lock the hydraulic pressure. At this time, if the piston rod 9 expands or contracts due to vibration or the like,
A damping force is generated by the bending action of the valves 27 and 28 provided on the piston 11, and the impact on the working machine is mitigated.

[Effect of the Invention] According to the present invention, the following effects are obtained.

The bracket is fitted to the outer circumference of the inner cylinder and has a cylindrical part sandwiched between the two outer tubes from both sides.The two outer tubes are arranged in series, so the length of the two outer tubes By adjusting and adjusting the axial fitting position of the cylindrical portion with respect to the inner cylinder, the hydraulic unit can be coupled to any position in the axial direction of the hydraulic cylinder via the bracket. Moreover, since the length of the inner cylinder is fixed and the hydraulic units are connected within the length range, it is not necessary to purposely lengthen the hydraulic unit in order to attach it. Therefore, the basic length of the hydraulic cylinder does not become long, and the mounting space is not restricted.

Since the hydraulic unit is fitted to the outer circumference of the inner cylinder via the cylindrical portion, the hydraulic unit can be arranged at any position in the circumferential direction of the inner cylinder by rotating the cylindrical portion. Moreover, the oil passage is provided between the inner cylinder and the outer cylinder, and the oil passage communicating with this oil passage is provided in the cylindrical portion. The pipes do not get entangled.

Since it is not necessary to lengthen the inner cylinder and the outer tube at the position where the bracket is attached and to make the outer tube thick, it is possible to prevent an increase in weight and an increase in material cost.

If a bracket is provided between the hydraulic unit and the hydraulic cylinder, the hydraulic unit and the hydraulic cylinder are installed in parallel in the same space to improve stability and also in a small axial space. Can be stored compactly.

[Brief description of drawings]

FIG. 1 is a partially longitudinal front view of a hydraulic unit and a hydraulic cylinder using a hydraulic unit mounting apparatus according to an embodiment of the present invention, FIG. 2 is a left side view of FIG. 1, and FIG. It is a partial longitudinal front view of a hydraulic unit and a hydraulic cylinder which used the installation device of a hydraulic unit. 1 ... hydraulic cylinder, 2 ... hydraulic unit, 7 ... inner cylinder, 8a, 8b ... outer tube, 19
... hydraulic pump, 20 ... hydraulic tank, 21 ... switching valve, 22 ... motor, 23 ... bracket, 23a ...
Cylindrical part, 23b ... Mounting part, 34, 35 ... Oil passage.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliography Sho 48-27339 (JP, Y1) Shoko 48-23031 (JP, Y1) Destined for application Sho 58-59035 (Act 59-164805) Of the description and drawings attached to the application of Microfilm (JP, U) Actual application No. 50-162180 (Ex. No. 52-74995) Micro film (JP, U) of the contents

Claims (2)

[Scope of utility model registration request] 1. A hydraulic cylinder having a double inner cylinder and an outer tube and a passage formed between the inner cylinder and the outer tube, an electric motor, a hydraulic pump, a hydraulic tank, and a switching valve. In a mounting device of a hydraulic unit in which the hydraulic unit is coupled to the hydraulic cylinder via a bracket, the bracket is integrally formed with the cylindrical portion fitted to the outer periphery of the inner cylinder. The outer tube is arranged in series along the axial direction outside the inner cylinder while sandwiching the cylindrical portion of the bracket from both sides, and the hydraulic unit is connected to the outer end of the mounting portion. Two oil passages are formed in the cylindrical portion and the mounting portion, and these oil passages are formed between the hydraulic cylinder and the outer cylinder. Mounting device for a hydraulic unit that are selectively connected to the hydraulic pump or the hydraulic tank via a switching valve with open respectively to the two passages is. 2. The mounting device for a hydraulic unit according to claim 1, wherein the hydraulic unit is connected to an intermediate position or an arbitrary position of the hydraulic cylinder via a bracket.