JPH1086620A - Vehicle with outrigger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely shorten the operation stroke of an outrigger and substantial miniaturize the outrigger compared with conventional ones in a vehicle with an outrigger capable of fixing the extension of the piston rod of a shock absorber when the outrigger is used. SOLUTION: A vehicle with outrigger is provided with a shock absorber 219, which is arranged between an axle 25 supported on a car body frame 11 through a suspension spring 23 and the car body frame 11 and has at least a pair of hydraulic cylinder, oil chamber communicating pipes, which communicates the head side oil chamber and the rod side oil chamber of each hydraulic cylinder, flow control means, which are arranged in each oil chamber communication pipe and restrict the flow rate of the oil passing through the oil chamber communication pipe to specified rate, pilot check valves, which are arranged in each oil chamber communication pipe, and an oil supply means, which supply oil to the pilot port of each pilot check valre which outriggers 21 are not being used and stop the supply of oil which the outriggers 21 are being used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle with an outrigger, and more particularly to a vehicle with an outrigger capable of fixing the extension of a piston rod of a shock absorber when the outrigger is used.

[0002]

2. Description of the Related Art Generally, vehicles equipped with outriggers such as crane trucks and aerial work vehicles are widely used at construction sites and construction sites. FIG. 3 shows such a vehicle with outriggers. In this vehicle with outriggers, a crane 3 is installed between a cab 1 and a carrier 2.

[0005] The crane 3 is fixed to a body frame 4, and a pair of outriggers 5 are attached to both sides of the body frame 4. Below cab 1,
Front shaft 7 supported on body frame 4 via suspension spring 6
Are arranged, and front wheels 8 are arranged at both ends of the front shaft 7. A shock absorber 9 is mounted between the vehicle body frame 4 and the front shaft 7 to attenuate the reaction force of the impact received by the suspension spring 6 from the ground.

In the vehicle with the outrigger described above, after the outrigger 5 is extended in the width direction of the vehicle, the outrigger rod 5a is extended downward so that the front wheel 8 can be lifted off the ground, and the vehicle is operated when the crane 3 is operated. It can be reliably stabilized.

[0005]

However, in the above-described vehicle with outriggers, when the vehicle is lifted using the outriggers 5, the shock absorber 9 is moved to the ground side by the urging force acting downward of the suspension spring 6. In order to completely lift the front wheel 7 off the ground, it is necessary to lift the vehicle higher than the operating stroke of the shock absorber 9, and the operating stroke of the outrigger 5 becomes large, and the outrigger 5 becomes large. Was.

In order to completely lift the front wheel 8 off the ground, it is necessary to lift the vehicle higher than the operating stroke of the shock absorber 9. Therefore, in order to stabilize the vehicle reliably, the outrigger 5 has a wide extension. Become
There was a problem that a large work space was required.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and it is possible to surely shorten the operation stroke of the outrigger and to significantly reduce the size of the outrigger. The purpose is to provide.

[0008]

According to a first aspect of the present invention, there is provided a vehicle with outriggers, wherein at least one pair of outriggers disposed on both sides of a body frame, an axle supported by the body frame via a suspension spring, and A shock absorber disposed between the vehicle body frame and having at least one pair of hydraulic cylinders, an oil chamber communication pipe for communicating a head side oil chamber and a rod side oil chamber of each of the hydraulic cylinders, and the oil chamber communication pipe Flow control means for restricting the flow rate of oil passing through the oil chamber communication pipe to a predetermined amount, a pilot check valve interposed in the oil chamber communication pipe, and the pilot valve when the outrigger is not used. Oil supply means for supplying oil to the pilot port of the check valve and stopping oil supply when the outrigger is used.

According to a second aspect of the present invention, in the vehicle with the outrigger according to the first aspect, the hydraulic supply means supplies or stops oil supplied from a hydraulic pump to the pilot port of the pilot check valve. An electromagnetic solenoid valve, and a lock switch that outputs a switching signal to the electromagnetic solenoid valve to switch an operation state of the electromagnetic solenoid valve.

A vehicle with an outrigger according to a third aspect is the vehicle with an outrigger according to the first or second aspect,
The flow regulating means is a flow control valve.

(Function) In the vehicle with the outrigger according to the first aspect, when the outrigger is not used, oil is supplied from the hydraulic pressure supply means to the pilot port of the pilot check valve, so that the pilot check valve is in a state in which the pilot check valve can flow backward, and the oil is discharged. It moves bidirectionally between the head side oil chamber and the rod side oil chamber of the hydraulic cylinder via the oil chamber communication pipe,
At this time, by the flow rate regulating means interposed in the oil chamber communication pipe,
The oil flow is limited to a predetermined amount, and the reaction force of the impact received by the suspension spring from the axle is attenuated.

When the outrigger is used, the supply of oil from the hydraulic pressure supply means to the pilot port of the pilot check valve is stopped, the pilot check valve is in a backflow cut-off state, and the oil from the rod-side oil chamber to the head-side oil is released. The movement to the chamber is blocked, and the extension of the piston rod of the shock absorber is fixed. In the vehicle with the outrigger according to the second aspect, the supply state of supplying oil from the electromagnetic solenoid valve to the pilot port of the pilot check valve and the supply of the oil are stopped by a switching signal input from the lock switch to the electromagnetic solenoid valve. The stop state is switched.

[0013] In the vehicle with the outrigger according to the third aspect, the flow rate of oil passing through the oil chamber communication pipe is changed by the flow control valve, and the damping speed of the shock absorber is adjusted.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows an embodiment of a vehicle with outriggers according to the present invention (corresponding to claims 1 to 3). In the drawing, reference numeral 11 denotes a body frame of a cab-back crane vehicle. . A cab 13 is disposed at a front portion (left side in the figure) of the body frame 11, and a carrier 1 is provided at a rear portion (right side in the figure) of the body frame 11.
5 are arranged.

A crane 17 is arranged between the cab 13 and the carrier 15, and the crane 17 is fixed to the body frame 11. A pair of outriggers 21 for accommodating the outrigger rods 19 are disposed on both sides of the body frame 11 near the crane 17. Below the cab 13, a front shaft 25 supported by the vehicle body frame 11 via a suspension spring 23 is arranged, and front wheels 27 are arranged at both ends of the front shaft 25.

Between the body frame 11 and the front shaft 25,
A pair of shock absorbers 29 are arranged. FIG.
Shows the shock absorber 29 and its vicinity. The shock absorber 29 is
have. A piston rod 33 is movably accommodated in the hydraulic cylinder 31.

A piston 34 is fixed to the upper end of the piston rod 33. The lower end of the piston rod 33 is fixed to the front shaft 25 or the suspension spring 23 shown in FIG. The hydraulic cylinder 31 has a head-side oil chamber 31 a and a rod-side oil chamber 31 b separated by a piston 34.

A pilot check valve 37 is connected to the head side oil chamber 31a of the hydraulic cylinder 31 via a first oil chamber communication pipe 35. Also, the hydraulic cylinder 31
A flow control valve 41 is connected to the rod-side oil chamber 31b via a second oil chamber communication pipe 39 (corresponding to claim 3). Further, a third oil chamber communication pipe 43 is connected between the pilot check valve 37 and the flow control valve 41.

The first oil chamber communication pipe 35 has one end open at the head side oil chamber 31a of the hydraulic cylinder 31.
The other end is connected to an inlet port of the pilot check valve 37.

The second oil chamber communication pipe 39 has one end open to the rod side oil chamber 31b of the hydraulic cylinder 31.
The other end is connected to one port of the flow control valve 41. The third oil chamber communication pipe 43 has one end connected to the outlet port of the pilot check valve 37 and the other end connected to the other port of the flow control valve 41.

An electromagnetic solenoid valve 47 is connected to the pilot check valve 37 via a pilot hydraulic pipe 45 (corresponding to claim 2). In this embodiment, the electromagnetic solenoid valve 47 is a PT connection (tandem center) type. The pilot hydraulic pipe 45 has one end connected to the pilot port of the pilot check valve 37 and the other end connected to the A port of the electromagnetic solenoid valve 47.

A drain pipe 49 is connected between the drain port of the pilot check valve 37 and the B port of the electromagnetic solenoid valve 47. A hydraulic pump 53 is connected to the electromagnetic solenoid valve 47 via a first hydraulic supply pipe 51. The first hydraulic supply pipe 51 is
One end is connected to the P port of the electromagnetic solenoid valve 47, and the other end is connected to the discharge port of the hydraulic pump 53.

The suction port of the hydraulic pump 53 is connected to a second hydraulic supply pipe 57 having a distal end opened to the oil tank 55. The T port of the pilot check valve 37 is connected to an oil recirculation pipe 59 whose tip is opened to the oil tank 55. Electromagnetic solenoid valve 4
7, a lock switch 61 for outputting a switching signal for switching the operation state of the electromagnetic solenoid valve 47 is connected via a switching signal line 63 (corresponding to claim 2).

In this embodiment, the switching signal is an electrical ON-OFF signal, and when the lock switch 61 is ON, a drive current for driving the electromagnetic solenoid of the electromagnetic solenoid valve 47 is output. Is done. In the vehicle with the outrigger described above, when the outrigger 21 shown in FIG. 1 is not used, the lock switch 61 is in the ON state.

In this state, a drive current is input from the lock switch 61 to the electromagnetic solenoid valve 47, oil flows from the P port to the A port, and the oil flows into the pilot port of the pilot check valve 37 through the pilot hydraulic pipe 45. Is supplied. Then, when a pilot pressure acts on the pilot port, the pilot check valve 37 is in a state in which the pilot flow can be reversely flowed, and the oil flows through the first oil chamber communication pipe 35 and the second oil through the pilot check valve 37 and the flow control valve 41. Room communication pipe 39, and
The hydraulic cylinder 31 bidirectionally moves between the head-side oil chamber 31a and the rod-side oil chamber 31b of the hydraulic cylinder 31 via the third oil chamber communication pipe 43.

At this time, when the oil passes through the flow control valve 41, the flow rate of the oil is limited to a predetermined amount, and the reaction force of the impact received by the suspension spring 23 from the front shaft 25 is attenuated. When the flow rate of the oil is changed by the flow control valve 41, the damping speed of the shock absorber 29 is adjusted.

On the other hand, when using the outrigger 21,
The lock switch 61 is turned off. In this state, the inflow of the oil flowing from the P port to the A port of the electromagnetic solenoid valve 47 is shut off, and the supply of the oil to the pilot port of the pilot check valve 37 is stopped.

When the pilot pressure at the pilot port is lost, the pilot check valve 37 is in a backflow blocking state, and the movement of oil from the rod side oil chamber 31b to the head side oil chamber 31a is interrupted. The extension of the rod 33 is fixed. In the vehicle with the outrigger configured as described above, the first oil chamber communication pipe 3 communicating the head side oil chamber 31a and the rod side oil chamber 31b of the hydraulic cylinder 31 of the shock absorber 29.
5, an electromagnetic switch in which a switching signal is input from a lock switch 61 by interposing a pilot check valve 37 in an oil chamber communication pipe line including a second oil chamber communication pipe 39 and a third oil chamber communication pipe 43; The solenoid valve 47 supplies oil to the pilot port of the pilot check valve 37 when the outrigger 21 is not used, stops the oil supply when the outrigger 21 is used, and fixes the extension of the piston rod 33 of the shock absorber 29. Because
The operation stroke of the outrigger 21 can be reliably shortened, and the outrigger 21 can be significantly reduced in size as compared with the related art.

Further, the oil supplied from the hydraulic pump 53 is supplied to or stopped from the pilot port of the pilot check valve 37 by the electromagnetic solenoid valve 47 to which a switching signal is inputted from the lock switch 61. The switching between supply of oil to the oil supply and stop of the oil supply can be performed by general-purpose components, and a wide range can be handled according to the pilot pressure of the pilot check valve 37.

Further, since the flow control valve 41 is interposed in the oil chamber communication pipe composed of the first oil chamber communication pipe 35, the second oil chamber communication pipe 39, and the third oil chamber communication pipe 43. Thus, the flow rate of oil passing through the oil chamber communication pipe can be changed, and the damping speed of the shock absorber 29 can be adjusted. In the above-described vehicle with outriggers, an example of a cab-back crane vehicle has been described. However, the present invention is not limited to such an embodiment. good.

In the vehicle with the outrigger described above, the piston rod 3 of the shock absorber 29 on the front shaft 25 side is used.
Although the example in which the extension of 3 is fixed has been described, the present invention is not limited to this embodiment, and the extension of the piston rod of the shock absorber on the rear shaft side can be fixed.

[0033]

As described above, in the vehicle with the outrigger according to the first aspect, the pilot check valve is connected to the oil chamber communication pipe that connects the head side oil chamber and the rod side oil chamber of the hydraulic cylinder of the shock absorber. When the outrigger is not in use, oil is supplied to the pilot port of the pilot check valve when the outrigger is not used, and when the outrigger is used, the supply of oil is stopped and the extension of the piston rod of the shock absorber is fixed. Therefore, the operation stroke of the outrigger can be reliably shortened, and the size of the outrigger can be significantly reduced as compared with the related art.

In the vehicle with the outrigger according to the second aspect, the oil supplied from the hydraulic pump is supplied to or stopped from the pilot port of the pilot check valve by an electromagnetic solenoid valve to which a switching signal is input from a lock switch. Therefore, switching between supply and stop of oil supply to the pilot port can be performed by general-purpose components, and a wide range can be handled according to the pilot pressure of the pilot check valve.

In the vehicle with the outrigger according to the third aspect, since the flow control valve is interposed in the oil chamber communication pipe, the flow rate of oil passing through the oil chamber communication pipe can be changed, and the damping speed of the shock absorber can be reduced. Can be adjusted.

[Brief description of the drawings]

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

FIG. 2 is a piping diagram showing a shock absorber of the vehicle with an outrigger of FIG. 1 and its vicinity.

FIG. 3 is a side view showing a conventional vehicle with outriggers.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Body frame 21 Outrigger 23 Suspension spring 25 Front axis 29 Shock absorber 31 Hydraulic cylinder 31a Head side oil chamber 31b Rod side oil chamber 35 First oil chamber communication pipe 37 Pilot check valve 39 Second oil chamber communication pipe 41 Flow control Valve 43 Third oil chamber communication pipe 47 Electromagnetic solenoid valve 53 Hydraulic pump 61 Lock switch

Claims (3)

[Claims] At least one pair of outriggers disposed on both sides of a body frame, and at least one pair of hydraulic pressures disposed between an axle supported on the body frame via a suspension spring and the body frame. A shock absorber having a cylinder, an oil chamber communication pipe communicating the head side oil chamber and the rod side oil chamber of each of the hydraulic cylinders, and an oil interposed in the oil chamber communication pipe and passing through the oil chamber communication pipe. A flow control means for limiting the flow rate of the outrigger to a predetermined amount; a pilot check valve interposed in the oil chamber communication pipe; supplying oil to a pilot port of the pilot check valve when the outrigger is not used; A vehicle with an outrigger, comprising: hydraulic supply means for stopping oil supply during use. 2. The vehicle with an outrigger according to claim 1, wherein the hydraulic supply means supplies or stops oil supplied from a hydraulic pump to the pilot port of the pilot check valve, and the electromagnetic solenoid. A lock switch for outputting a switching signal to a valve to switch an operation state of the electromagnetic solenoid valve; and a vehicle with an outrigger. 3. The vehicle with outriggers according to claim 1, wherein said flow rate regulating means is a flow rate control valve.