JPS6228330B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a single acting cylinder device.

[Conventional technology]

In a single-acting cylinder device in which the piston is driven by fluid pressure applied from one axial direction and elastic force applied from the other, the piston is small and lightweight, and the piston is driven by a force in a direction perpendicular to the axial direction. In order to prevent the piston from being tilted or eccentric, a protrusion 2 protruding from the cylinder 1 is fitted into a recess 4 of the piston 3, as shown in FIG. 4 and the protrusion 2, and flows into a cylinder chamber 7 formed on one side of the piston 3 in the axial direction.

[Problem that the invention seeks to solve]

In such a conventional device, the protrusion 2, the recess 7, etc. must be provided, and the spring member 8, etc. must be provided on the other side in the axial direction, so there is a limit to how thin the device can be made. Therefore, for example, when the cylinder device is attached to the end of a plate of a stacked leaf spring device for a vehicle, there is a risk that the cylinder device may interfere with the vehicle body. Under these circumstances, it has been desired to develop a thin single-acting cylinder device with a short axial length.

[Means for solving problems]

The single-acting cylinder device of the present invention includes a cylinder which has a cylinder chamber inside and is provided with a disc spring support part along the circumferential direction on the inner surface side, and a disc spring support part inserted into this cylinder and along the circumferential direction on the outer surface side. A piston provided with a disc spring support, and a piston provided between the cylinder and the piston, the outer peripheral part of which is engaged with the disc spring support of the cylinder, and the inner peripheral part of which is engaged with the disc spring support of the piston. a locked disc spring; sealing means for sealing between the outer periphery of the disc spring and the cylinder; and between the inner periphery of the disc spring and the piston, and the disc spring, the piston, and the cylinder. A hydraulic chamber is formed in the area surrounded by.

[Function] The present invention provides a return disc spring whose outer and inner peripheral parts are supported by the cylinder and the piston, respectively, so that the piston can be supported by the disc spring. There is no need to provide a protrusion in the cylinder or a recess formed in the piston to fit the protrusion. Further, since the disc spring is located in the outer circumference of the piston and constitutes a part of the hydraulic chamber together with the piston, the length of the entire device, especially in the axial direction, can be significantly shortened. Therefore, it is lightweight and low cost, and even when applied to a stacked leaf spring device for a vehicle, there is no possibility of interference with the vehicle body.

〔Example〕

FIG. 2 illustrates a case where the single-acting cylinder device 10 according to the present invention is applied to a stacked leaf spring device a for a vehicle. This cylinder device 10 includes a cylinder 11 as shown in FIG. This cylinder 11 consists of a plate-shaped cylinder main body 11a and a flange portion 23 described below. The above cylinder body 11a
has a cylinder chamber 12 that opens on one side in the thickness direction, and has an inner step 13 formed at the inner peripheral edge of the cylinder chamber 12 and an outer step 14 as a disc spring support. . Furthermore, a fluid communication hole 15 communicating with the cylinder chamber 12 is provided in the cylinder body 11a.

A main body portion 16a of the piston 16 is fitted into the cylinder chamber 12. This piston body part 1
6a has an inner stepped portion 17 and an outer stepped portion 18 as a disc spring support portion formed on the outer peripheral edge thereof. Further, the piston body portion 16a includes a piston rod portion 1 that constitutes a part of the piston 16.
9 are integrally attached.

The returning disc spring 20 has an inner circumferential portion fitted and supported by the inner stepped portion (disc spring support portion) 17 of the piston 16, and an outer circumferential portion fitted into and supported by the outer stepped portion (disc spring support portion) of the cylinder 11. ) 14 is fitted and supported. In addition, the outer periphery of the disc spring 20 and the cylinder 1
An O-ring 21 serving as a sealing means is provided between the inner step portion 13 and the inner step portion 13 of the inner step portion 1 . Furthermore, disc spring 2
An O-ring 22 serving as a sealing means is also provided between the inner peripheral portion of the piston 16 and the outer stepped portion 18 of the piston 16.

Furthermore, a flange portion 23 that constitutes a part of the cylinder 11 is provided on one side of the cylinder body 11a. The flange portion 23 includes a recess 24 facing the cylinder chamber 12 and a through hole 25 into which the piston rod portion 19 is inserted so as to be able to reciprocate.
6 is installed. The recess 24 is formed to accommodate the maximum amount of deflection of the disc spring 20 corresponding to the maximum stroke of the piston 16.

A hydraulic chamber 50 is formed in a region surrounded by the disc spring 20, cylinder 11, and piston 16. This hydraulic chamber 50 has the communication hole 15
Pressure oil or fluid enters through.

The cylinder device 10 having the above configuration includes an upper plate 2 that sandwiches the plate ends of the stacked leaf spring device a in the thickness direction.
7 and the lower plate 28 by bolts 29 and nuts 30. In addition, 3 in the figure
1 is a liner, and 32 is a spacer.

In the device configured as described above, when pressurized fluid is injected into the hydraulic chamber 50 from the flow hole 15, the piston 16 is displaced downward against the elastic force of the disc spring 20, and the piston rod portion 19 and the upper Board 27
The plate end portion of the stacked plate spring device a is pressed in the thickness direction via the liner 31. Further, if the pressure of the pressure fluid is reduced, the piston 16 is pushed up by the restoring force of the disc spring 20, and the pressing force against the stacked leaf spring device a is also reduced. By appropriately controlling this pressing force, the frictional force between the plates can be variably controlled, improving riding comfort and handling stability.

According to the above configuration, the inner circumferential portion of the disc spring 20 is supported by the outer circumferential portion of the piston 16, that is, the stepped portion 17,
In addition, since the outer circumferential portion of the piston 16 is supported by the inner circumferential portion of the cylinder 11, that is, the stepped portion 14,
The piston 16 is connected to the cylinder 11 via a disc spring 20.
Supported by Therefore, the piston 16 does not come into sliding contact with the inner circumferential wall of the cylinder chamber 12, and there is no need to provide the protrusion 2 (see FIG. 1), recess 4, etc. required in the conventional device.

Further, since the disc spring 20 is located in the outer circumference of the piston 16 and constitutes a part of the hydraulic chamber 50 together with the piston 16, the length of the entire device, especially in the axial direction, can be significantly shortened. Therefore, even if it is attached to the vehicle stacked leaf spring device a, it will not interfere with the vehicle body. Furthermore, since the structure is simple, it can be made compact and can be manufactured at low cost.

Note that the present invention is not limited to the above-mentioned embodiments. For example, as shown in FIG. Disc spring 2 when
The piston 16 may be configured to rise against a repulsive force of 0, and then descend due to the restoring force of the disc spring 20 when the fluid pressure decreases. Further, a plurality of disc springs 20 may be used in combination as necessary. In addition, various modifications and applications are possible within the scope of the gist of the present invention.

〔Effect of the invention〕

According to the present invention, the structure is simpler than that of conventional single-acting cylinder devices, and the axial length can be significantly shortened, which is extremely effective in reducing the size of the entire device.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a conventional single-acting cylinder device, Fig. 2 is a side view of an embodiment in which the cylinder device of the present invention is applied to a stacked leaf spring device, and Fig. FIG. 4 is a sectional view taken along the line -, and FIG. 4 is a sectional view showing a modification of the main part. 10...Cylinder device, 11...Cylinder, 1
1a...Cylinder body, 12...Cylinder chamber, 1
4... Outer step (disc spring support), 16... Piston, 16a... Piston main body, 17... Inner step (disc spring support), 19... Piston rod, 20... Disc spring, 21, 22...O ring (sealing means), 50...hydraulic chamber.

Claims (1)

[Scope of Claims] 1. A cylinder that has a cylinder chamber inside and is provided with a disc spring support that extends circumferentially on the inner surface, and a disc spring support that is inserted into this cylinder and that extends circumferentially on the outer surface. and a piston provided between the cylinder and the piston, the outer peripheral part of which is locked to the disc spring support part of the cylinder, and the inner peripheral part of which is locked to the disc spring support part of the piston. a disc spring, and sealing means for sealing between the outer circumference of the disc spring and the cylinder, and between the inner peripheral part of the disc spring and the piston, and surrounded by the disc spring, the piston, and the cylinder. A single-acting cylinder device characterized by having a hydraulic chamber formed in the area where the hydraulic pressure is applied.