JP2000143196A - Oscillation regulation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oscillation regulation device capable of widening a range of application by shortening a mount distance without impairing the oscillation feeling and the operating stroke in both directions, and preventing the leakage of the hydraulic fluid without manufacturing each component in high accuracy in view point of structure. SOLUTION: In this oscillation regulating device 1, the piece rod cylinders 5, 6 are mounted between the relatively oscillated vehicle body side 3 and wheel side 4 in parallel with each other in the oscillating direction while facing to the same direction, and the communication and cutting of the head side oil chambers 7, 9 and the rod side oil chambers 8, 10 for piece rod cylinders 5, 6 are separately on and off controlled by the independent control valves 11, 12. On this occasion, the head side oil chambers 7, 9 and the rod side oil chambers 8, 10 of the piece rod cylinders 5, 6 are respectively communicated with the reservoir tanks 19, 20 only when the control valves 11, 12 control the switching to the communicating positions of the head side oil chambers 7, 9 and the rod side oil chambers 8, 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swing restricting device for suppressing a lateral swing generated between two objects that relatively swing, such as a vehicle body and a wheel, in an industrial vehicle such as a forklift. In particular, the present invention relates to an improved structure of this type of rocking control device, which can be applied to a wide range by reducing the mounting length of the rocking control device as much as possible.

[0002]

2. Description of the Related Art In this type of rocking control device conventionally used in forklifts and the like, both rod cylinders are interposed between a vehicle body and a wheel side, and the compression of the rod cylinders is performed. By controlling both the extension and the extension, the load is supported by both, eliminating the pressure receiving area difference between both rod cylinders during the compression and extension, thereby suppressing the roll while maintaining the same swinging feeling in both directions. I've been doing so.

[0003]

However, in this case, since the cylinder itself for restricting the swinging movement between the vehicle body side and the wheel side is a double rod type cylinder, the axial length is large. As a result, it cannot be made compact in the vertical direction, and the distance between the mountings becomes long.

[0004] For this reason, depending on the type of application, the distance between the vehicle body side and the wheel side is too short, and it is difficult to mount both rod cylinders for restricting the swinging motion.
As a result, there has been a problem that the application target for mounting the swing regulation device using both rod cylinders is limited.

[0005] In addition to this, the cylinder itself for regulating the swinging motion is a double rod type cylinder, and many components are slidably combined from the structural point of view, and individual components are not configured with high precision. In addition, there is a disadvantage that the production oil requires a lot of trouble and time, resulting in an increase in cost.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to make the whole compact without sacrificing the swinging feeling and working stroke in both directions, to shorten the distance between mountings, to broaden the applicable range, and to improve the structure. Another object of the present invention is to provide a rocking control device of this kind which can prevent the leakage of hydraulic oil without keeping the production of each component with high precision.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to dispose a single rod cylinder in the same direction between two objects which are relatively oscillating in the same direction. The communication and disconnection of the head-side oil chamber and the rod-side oil chamber are controlled on / off by individual control valves for each rod cylinder, and the control valve switches the head-side oil chamber and the rod-side oil chamber to the communication position. This is achieved only by controlling the head-side oil chamber and the rod-side oil chamber of the one-rod cylinder to communicate with the reservoir tanks on the respective sides only during control.

That is, in the above-mentioned prior art, in order to make the swinging feeling in the right and left directions the same, the two rod cylinders are used to eliminate the area difference. Because of the cylinder, the distance between the attachments becomes extremely long, and in order to mount the object between two objects having a predetermined interval, the regulation range has to be considerably reduced at the expense of the stroke.

However, simply replacing both rod cylinders with single rod cylinders causes a difference in the swinging feeling in the left and right direction due to the area difference between the head side oil chamber and the rod side oil chamber. Would.

In this respect, according to the present invention, a plurality of single rod cylinders are interposed in the same direction in the swinging direction between two objects that relatively swing and move, so that one of the one rod cylinders is interposed. When the rod cylinder is compressed, the other one-side rod cylinder extends.

[0011] This makes it possible to reduce the distance between mountings and increase the range of applications without sacrificing the swinging feeling in both directions and the working stroke length, while reducing the overall size.

In addition, compared to the two rod cylinders, there is less sliding combination of the components, and a single rod cylinder which has a relatively low risk of hydraulic oil leakage even if individual components are not formed with high precision. The swing restriction device can be configured at low cost.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A hydraulic cylinder according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, a swing restricting apparatus 1 according to the present invention is provided between a body side 3 and a wheel side 4 of a forklift vehicle, for example, two objects which swing relatively around an axis 2. It has a pair of left and right single rod cylinders 5 and 6 which are symmetrically arranged in the swinging direction with the shaft 2 interposed therebetween and arranged in an inverted manner.

These single-rod cylinders 5 and 6 are connected to a head-side oil chamber 7 and a rod-side oil chamber 8 of the single-rod cylinder 5 on the left and a head-side oil chamber 9 of the single-rod cylinder 6 located on the right. The head-side oil chamber 7 and the rod-side oil chamber 8 and the head-side oil chamber 9 and the rod-side oil chamber 10 are normally closed so that the communication and cutoff of the rod-side oil chamber 10 can be individually controlled on / off. The oil passages 13 and 14 and the oil passages 15 and 16 are used to connect to control valves 11 and 12 each of which is a port 2 position solenoid valve.

In addition, these oil passages 13 and 14 and oil passage 1
5 and 16 are control valves 11 and 12 respectively.
At the exit side after passing through the common oil passage 17,
18, the oil passages 17 and 18 individually communicate with the reservoir tanks 19 and 20 on the respective sides.

Thus, when the vehicle travels with an empty load or the like, the control valves 11 and 12 are switched to the open state by a command signal from the controller 21, and the head-side oil chamber 7 of the one rod cylinder 5 located on the left side is opened. And the rod-side oil chamber 8, and the oil passages 13 and 14 from the head-side oil chamber 9 and the rod-side oil chamber 10 of the single-rod cylinder 6 located to the right.
And oil passages 15 and 16 to common oil passages 17 and 18, respectively.

As a result, the head side oil chambers 7, 9 in the single rod cylinders 5, 6 respectively communicate with the rod side oil chambers 8, 10, and also communicate with the reservoir tanks 19, 20 through common oil passages 17, 18. Lead to individual.

Therefore, the left and right single rod cylinders 5 and 6 expand and contract in the opposite direction while alternately contracting and expanding these reservoir tanks 19 and 20 in accordance with the roll between the vehicle body side 3 and the wheel side 4. Operate and travel while elastically supporting the vehicle body side 3 with respect to the wheel side 4 by a suspension spring (not shown) or an air spring accompanying contraction and expansion of the reservoir tanks 19 and 20 or a combined spring action of both. become.

On the other hand, when there is a possibility that the vehicle body side 3 may be tilted or the front wheels are lifted due to a sharp turn during work, for example, in the case of a forklift, the weight of the load, the height of the mast, and the lateral direction Various operation information such as acceleration is caught by a sensor and input to the controller 21, and the control valves 11 and 12 are switched to a closed state and held by a command signal from the controller 21.

As a result, the left-side oil chamber 7 and the rod-side oil chamber 8 of the one-rod cylinder 5 on the left and the head-side oil chamber 9 and the rod-side oil chamber 10 of the one-rod cylinder 6 located on the right Since the communication is interrupted by the control valves 11 and 12 at the same time, the one-sided rod cylinders 5 and 6 regulate the rear side sway of the vehicle body 3 to maintain the balance while increasing the treading force.

In the embodiment of FIG. 1 described above, a normally closed 4-port 2-position solenoid valve has been used as the control valves 11 and 12, but instead of this, the second valve shown in FIG. As in the swing restriction device 1a according to the present embodiment, a normally closed 3-port 2-position ABR connection solenoid valve that is inexpensive and easy to pipe compared to the 4-port 2-position solenoid valve may be used.

The oil passages 13 and 14 and the oil passages 15 and 16 extending from the head side oil chambers 7 and 9 and the rod side oil chambers 8 and 10 in the single rod cylinders 5 and 6 are connected to the control valves 11 and 12 on each side. The connection was made separately to the AB port and the R port was connected to the reservoir tanks 19 and 20 on the respective sides by common oil passages 17 and 18.

According to this, the control valves 11 and 12 are switched to the open state based on a command signal from the controller 21 when the vehicle travels with an empty load.
The head-side oil chamber 7,
9 and the rod-side oil chambers 8 and 10 are shared by common oil passages 17 and 18.
From the reservoir tanks 19 and 20 on each side.

For this reason, even in the swing regulating device 1a, the left and right single rod cylinders 5, 6 are connected to the reservoir tanks 19, similarly to the swing regulating device 1 shown in the embodiment of FIG. , 20 alternately expand and contract in the opposite direction while contracting and expanding, and are effected by a suspension spring (not shown), an air spring accompanying the contraction and expansion of the reservoir tanks 19, 20, or a combined spring action of both. The vehicle travels while elastically supporting the vehicle body side 3 with respect to the wheel side 4.

On the other hand, at the time of work, the control valves 11, 12 are switched to the shut-off state based on command signals from the controller 21 based on various operation information, and the left and right single rod cylinders 5, 6 are locked. While being kept separate from the reservoir tanks 19 and 20, the single rod cylinders 5 and 6 regulate the rear side sway of the vehicle body 3 to maintain the balance while increasing the treading force.

FIG. 3 shows a swing restricting device 1b according to a third embodiment. In this device, the control valves 11 and 12 are of a normally closed type which is more inexpensive and easy to pipe. A 2-port 2-position solenoid valve is used.

Then, the rod-side oil chambers 8 and 10 of the single rod cylinders 5 and 6 are moved from the oil paths 14 and 16 to the common oil paths 17 and
18 and the reservoir tanks 19 and 20 at all times, and the head side oil chambers 7 and 9 are passed through the control valves 11 and 12 on the respective sides by oil paths 13 and 15, respectively.
In addition, they communicated with the rod-side oil chambers 8 and 10 and the reservoir tanks 19 and 20 through oil paths 17 and 18 that are common to the oil paths 14 and 16.

Even in this case, when the vehicle travels with an empty load, the control valves 11 and 12 are switched to the open state based on a command signal from the controller 21.
The head-side oil chamber 7,
9 and the rod-side oil chambers 8 and 10 are shared by common oil passages 17 and 18.
From the reservoir tanks 19 and 20 on each side.

Thus, the right and left single rod cylinders 5 and 5 are also provided in the swing restriction device 1b, similarly to the swing restriction devices 1 and 1a shown in the embodiment of FIGS.
6 expands and contracts in opposite directions while alternately contracting and expanding these reservoir tanks 19 and 20;
The vehicle travels while elastically supporting the vehicle body side 3 with respect to the wheel side 4 by the action of a suspension spring (not shown), an air spring accompanying the contraction and expansion of the reservoir tanks 19 and 20, or a combined spring action of both.

Further, during operation, the control valves 11 and 12 are switched to the shut-off state by a command signal from the controller 21 based on various operation information, and the head side of the left and right single rod cylinders 5 and 6 on the load supporting side. While keeping the oil chambers 8 and 10 in a locked state, the oil chambers 8 and 10 are also separated from the reservoir tanks 19 and 20, and the one-side rod cylinders 5 and 6 are used to restrict the rearward sway of the vehicle body 3 and maintain a balance while increasing a treading force. become.

In the above-described swing restricting device 1b according to the third embodiment shown in FIG. 3, the rod-side oil chambers 8 and 10 in the single rod cylinders 5 and 6 are provided with oil on each side. The passages 14 and 16 and the common oil passages 17 and 18 are always in communication with the reservoir tanks 19 and 20.

Therefore, in the swing regulating device 1b of the third embodiment shown in FIG.
When the cylinder 12 is shut off, the head-side oil chambers 7 and 9 of the single-rod cylinders 5 and 6 are locked by the control valves 11 and 12, but the rod-side oil chambers 8 and 10 are connected to the reservoir tanks 19 on the respective sides. , 20 remain in communication.

As a result, in response to the roll between the vehicle body side 3 and the wheel side 4 generated during the work, the controller 2
The head side oil chambers 7 and 9 of the single rod cylinders 5 and 6 held in a locked state by the control valves 11 and 12 that are switched based on a command signal from 1 exert a restricting action while resisting contraction. I do.

However, on the other hand, on the floating side,
The rod-side oil chambers 8 and 10 of the single rod cylinders 5 and 6 are not locked by the controller control valves 11 and 12 and remain connected to the reservoir tanks 19 and 20 on the respective sides. Can hardly exert resistance.

From this, the left and right single rod cylinders 5, 6 exert resistance only on the sinking side against the roll between the vehicle body side 3 and the wheel side 4, and almost act on the opposite floating side. Without doing so, the left and right single rod cylinders 5
Since the roll is alternately suppressed at 6, the hydraulic oil pressure applied to the head side oil chambers 7, 9 of the single rod cylinders 5, 6 increases by that amount, and there is a concern that hydraulic oil leaks.

FIG. 4 shows a modification of the swing regulation device 1b according to the third embodiment of FIG. 3 in which the above-described measures have been taken. The fourth embodiment shown in FIG. In the swing restriction device 1c of the embodiment, the first control valves 11 and 12 are interposed in the middle of the oil passages 13 and 14, and the first control valve is also provided in the middle of the common oil passages 17 and 18. Second control valves 22 and 23, which are normally closed 2-port 2-position solenoid valves similar to 11 and 12, are provided.

The control valves 22 and 23 are switched in synchronization with the control valves 11 and 12 in response to a command signal from the controller 21 so as to be combined with the head side oil chambers 7 and 9 of the single rod cylinders 5 and 6. The rod-side oil chambers 8 and 10 are also kept in a locked state, and the left and right single-rod cylinders 5 and 6 can be effectively prevented from rolling between the vehicle body side 3 and the wheel side 4.

However, in the swing restriction device 1c according to the fourth embodiment shown in FIG. 4, the first and second control valves 11, 12, 22, and 23 are switched to open. Then, it is assumed that an abnormal situation occurs in which the second control valve 22 or 23 does not open due to a failure or the like.

When the first control valve 11 or 12 is opened, the head side of the single rod cylinder 5 or 6 and the rod-side oil chambers 7 and 8 or 9 and 10 communicate with each other.
The load applied between the vehicle body side 3 and the wheel side 4 is received by the rod cross-sectional area of the single rod cylinder 5 or 6, which may cause damage to the single rod cylinder 5 or 6.

Therefore, in the swing regulating device 1d according to the fifth embodiment shown in FIG. 5, the first control valves 11, 12 and the reservoir tanks 19, 20 are connected to the second control valves 22, It was tied without going through 23.

As a result, the second control valve 22
Or even if the state where the 23 does not open occurs,
The load applied between the single rod cylinder 5 or 6 and the wheel side 4 is not received by the rod cross section of the single rod cylinder 5 or 6 but by the piston cross section of the single rod cylinder 5 or 6.

As shown in the embodiments of FIGS. 3, 4 and 5 described above, the second control valves 22 and 23 are used together with the first control valves 11 and 12. However, it is needless to say that, for example, by using a non-leak valve with a built-in check valve, the roll caused between the vehicle body side 3 and the wheel side 4 can be more effectively suppressed.

[0044]

As described above, according to the first aspect of the present invention, a single rod cylinder is interposed in the same direction by arranging two objects relatively oscillating in the direction of oscillation. The communication and disconnection between the head-side oil chamber and the rod-side oil chamber are controlled on / off by individual control valves for each individual rod cylinder, and the communication position between the head-side oil chamber and the rod-side oil chamber by the control valve. Only at the time of the switching control, the head side oil chamber and the rod side oil chamber of the single rod cylinder are configured to communicate with the reservoir tanks on each side, so that the swing feeling and the operation stroke in both directions can be reduced. By shortening the cylinder length and shortening the mounting dimensions without sacrificing, the range of applicable applications can be expanded, and also from the structural point of view, the sliding combination of each component is reduced. Comb without keeping the manufacturing with high precision, can be prevented easily even leakage hydraulic oil while achieving cost reduction.

According to the second aspect of the present invention, the above-mentioned effects are achieved while adding economical effects by using a normally closed 2-port 2-position solenoid valve having a simple structure and an inexpensive structure as a control valve for control. It becomes possible to do.

Further, according to the third aspect of the present invention, the above-described effects can be more effectively exerted only by adding an inexpensive control valve having a simple structure to the second aspect of the present invention. can do.

Further, according to the present invention, even if the control valve does not open due to a failure or the like, the load applied between the vehicle body and the wheel is received by the rod cross-sectional area of the single rod cylinder. Instead, the single rod cylinder can be prevented from being damaged by receiving the single rod cylinder with the piston cross-sectional area.

[Brief description of the drawings]

FIG. 1 is a principle diagram showing an embodiment of a swing restriction device according to the present invention for suppressing a swing motion generated between two objects.

FIG. 2 is a principle view showing another embodiment of the swing regulation device according to the present invention.

FIG. 3 is a principle view showing another embodiment of the swing regulation device according to the present invention.

FIG. 4 is a principle view showing an embodiment of a swing regulation device which is a modification of the invention of FIG. 3;

FIG. 5 is a principle view showing another modification of the swing regulation device obtained by improving the invention of FIG. 4;

[Explanation of symbols]

 1, 1a, 1b, 1c, 1d Swing control device 2 shaft 3 Car body side 4 Wheel side 5,6 Single rod cylinder 7,9 Head side oil chamber 8,10 Rod side oil chamber 11,12 (first) control Valve 19, 20 Reservoir tank 21 Controller 22, 23 Second control valve

Claims (4)

[Claims] 1. A single rod cylinder is interposed in the same direction between two objects that are relatively oscillating and arranged in the swinging direction, and a head-side oil chamber and a rod-side oil chamber are provided for each of these single-rod cylinders. The on / off control of the communication and the cutoff of each of the head-side oil chambers in the single rod cylinder is performed only when the control valve switches the head-side oil chamber and the rod-side oil chamber to the communication position. And a rod-side oil chamber communicates with the reservoir tank on each side. 2. A single-rod cylinder is interposed in the same direction between two objects that relatively oscillate in a swinging direction, and a rod-side oil chamber is always provided for each of the single-rod cylinders on each side. To the reservoir tank,
A swing restriction characterized in that the head-side oil chamber in each single-rod cylinder is intermittently controlled to the rod-side oil chamber and the reservoir tank on each side through control valves for on / off control respectively. apparatus. 3. A single rod cylinder is interposed in the same direction between the two objects which are relatively oscillating and arranged in the oscillating direction, and a rod-side oil chamber is turned on / off for each of these single rod cylinders. The first control valve for control is connected to the reservoir tank on each side, and the head side oil chamber in the single rod cylinder is turned on / off.
The intermittent control is performed to the rod-side oil chamber on the same side through the second control valve for off control, and from the second control valve to the reservoir tank on each side through the first control valve. A swing restricting device characterized by comprising. 4. A single rod cylinder is interposed in the same direction between the two objects which are relatively oscillating and arranged in the swinging direction, and the rod-side oil chamber is turned on / off for each of these single rod cylinders. Connect to the reservoir tank on each side through the first control valve for control, and intermittently control the oil chamber on the head side to the reservoir tank on each side also through the second control valve for on / off control. A swing restricting device characterized by comprising.