JP2003096830A - Cargo handling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cargo handling device which is used for a working vehicle (construction vehicle) such as a wheel loader and allows the rising of a boom to be easily controlled with an operation of a bucket lever. SOLUTION: This cargo handling device is composed of a boom cylinder 2, a bucket cylinder 3, a boom control valve 4, a bucket control valve 6, a boom lever 6, the bucket lever 7 and a boom control switch 8; and above all, the bucket lever 7 is provided with the control switch 8 which controls the control valve 4 so as to control the rising of the boom 52.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a cargo handling operation device used for a work vehicle (construction vehicle) such as a wheel loader.

[0002]

2. Description of the Related Art In a work vehicle such as a large wheel loader, two levers for a boom and a bucket are operated to carry out cargo handling work. When the vehicle moves forward with it level with the ground, and when it has sufficiently thrust into the object to be handled, the bucket lever is tilted a few times backward while keeping the boom lever in the raised position while applying the traction force to raise the bucket. Therefore, I try to scoop things into the bucket. However, with such a method, even when there is no item to be handled in the bucket, the boom automatically raises, so it may not be possible to scoop the item sufficiently. Therefore, it is necessary for the operator to operate the boom lever while controlling the bucket lever to operate the boom lever. In other words, the boom had to be lifted again after the traction force was exerted by pushing the boom lever once to stop the boom ascent and further pushing in. However, such an operation is very complicated and requires skill.

By the way, as a cargo handling operation device, for example, the one described in Japanese Utility Model Publication No. 7-2725 is known. This is a boom cylinder that raises and lowers the boom with respect to the vehicle body, a bucket cylinder that raises and lowers the bucket with respect to the boom, a boom control valve that controls the boom cylinder, a bucket control valve that controls the bucket cylinder, and a boom control. Boom lever that operates the valve, bucket lever that operates the bucket control valve, bucket control switch that is provided at the grip of the boom lever and can be operated in the up and down directions, and when operating the bucket control switch And a timer that operates the bucket control valve in a predetermined direction for a certain period of time. Thus, since such a thing can make the bucket an appropriate angle while holding the boom lever, it is optimal when the operation of operating the boom lever is mainly performed.

[0004]

However, in the case where the so-called bucket lever is mainly operated, in which the boom is controlled to be raised while operating the bucket lever as in the case of scooping, It wasn't suitable. Further, since a switch and a timer for controlling both the up and down movement of the bucket are required, the structure is complicated and the cost is high. The present invention was devised in order to solve the above problems in view of the above problems, and the problem is to perform a cargo handling operation capable of easily controlling the boom rise while operating the bucket lever. To provide the equipment.

[0005]

SUMMARY OF THE INVENTION A cargo handling operation device of the present invention basically comprises a boom cylinder for raising and lowering a boom with respect to a vehicle body, a bucket cylinder for raising and lowering a bucket with respect to the boom, and a boom cylinder. The boom control valve for controlling, the bucket control valve for controlling the bucket cylinder, the boom lever for operating the boom control valve, the bucket lever for operating the bucket control valve, and the boom control valve provided on the bucket lever for controlling the boom control valve. The feature is that it is composed of a boom control switch that controls the raising of the boom.

When the boom lever is operated, the boom control valve is controlled to operate the boom cylinder, and the boom is moved up and down with respect to the vehicle body. When the bucket lever is operated, the bucket control valve is controlled, the bucket cylinder is operated, and the bucket is elevated to the boom. If you operate the boom control switch while holding the bucket lever,
The boom control valve is controlled to control the raising of the boom.
Therefore, the boom can be controlled to be raised while operating the bucket lever, and the scooping operation can be properly and easily performed. Since it is not necessary to grip the bucket lever with the boom lever, the operation is easy and the operator's fatigue is reduced.

The boom control valve preferably includes a boom main valve and a boom pilot valve for pilot-controlling the boom main valve. With this configuration, the boom main valve can be installed at an arbitrary position, and quick and reliable control can be performed.

The boom control switch is provided between the boom main valve and the boom pilot valve to control the on-off type solenoid valve for controlling the rising pilot pressure, and the boom control switch is provided at the grip portion of the bucket lever to control the on-off type solenoid valve. And an on / off type switch for switching on and off. By doing so, the structure can be simplified and the cost can be reduced.

The boom control switch is provided between the boom main valve and the boom pilot valve to control the proportional pilot pressure, and a proportional solenoid valve provided at the grip of the bucket lever to control the proportional solenoid valve. And a variable type switch for By doing this, it is possible to finely control the rise of the boom.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a hydraulic circuit diagram showing a cargo handling operation device of the present invention. FIG. 2 is a side view showing the work vehicle.

The cargo handling operation device 1 is mainly composed of a boom cylinder 2, a bucket cylinder 3, a boom control valve 4, a bucket control valve 5, a boom lever 6, a bucket lever 7, and a boom control switch 8. It is applied to a work vehicle 50 such as a wheel loader.

The work vehicle 50 includes a vehicle body 51, a boom 52 that can be elevated on the vehicle body 51, the vehicle body 51 and the boom 52.
Between the boom cylinder 2 provided between the boom cylinder 52 and the bucket 53, a bucket (working tool) 53 provided on the boom 52 so as to be elevated, a bell crank 54 rotatably provided on the boom 52, and the bucket 53. Push rod 5 provided between
5 and the bucket cylinder 3 provided between the vehicle body 51 and the bell crank 54.

The boom cylinders 2 raise and lower the boom 52 with respect to the vehicle body 51. In this example, the boom cylinders 2 are a pair of left and right and are provided between the vehicle body 51 and the boom 52.

The bucket cylinder 3 elevates the bucket 53 with respect to the boom 52. In this example, the bucket cylinder 3 is single, and a push rod 55 and a bell crank 54 are provided between the bucket 53 and the vehicle body 51. It is provided.

The boom control valve 4 controls the boom cylinder 2. In this example, the boom control valve 4 is provided with a boom main valve 9 for controlling the boom cylinder 2 and a boom pilot valve 10 for pilot-controlling the boom main valve 9.

The bucket control valve 5 is a bucket cylinder 3
In this example, a bucket main valve 11 that controls the bucket cylinder 3 and a bucket pilot valve 12 that pilot-controls the bucket main valve 11 are provided.

The boom lever 6 operates the boom control valve 4. In this example, the boom lever 6 is tiltably provided to operate the boom pilot valve 10, and the grip portion 1 is provided at the upper end.
3 is provided.

The bucket lever 7 operates the bucket control valve 5, and in this example, the bucket pilot valve 1
It is provided so that it can be tilted to operate 2, and a grip portion 14 is provided at the upper end.

The boom control switch 8 is provided on the bucket lever 7 and controls the boom control valve 4 to control the raising of the boom 52. In this example, the boom main valve 9 is used.
An on-off type solenoid valve 15 provided between the boom pilot valve 10 and the boom pilot valve 10 to control the rising pilot pressure, and an on-off type switch 16 provided to the grip portion 14 of the bucket lever 7 to control the on-off type solenoid valve 15. Is equipped with. The on-off type solenoid valve 15 is provided on the ascending pilot line of the ascending pilot line and the descending pilot line between the boom main valve 9 and the boom pilot valve 10, and is a 4-port 2-position solenoid valve. The pump port is the boom pilot valve 10, the tank port is the tank 17, and the A port is the boom main valve 9.
In addition, the B port is blind. On-off type switch 16
Is a push button switch.

Boom main valve 9 and bucket main valve 11
Together with a line relief valve, a check valve, etc. (not shown) make up the main valve, and the bucket main valve 11 has a priority tandem circuit, and the pump port has a main pump 18 Is connected, and the tank 17 is connected to the tank port. The boom pilot valve 10 and the bucket pilot valve 12 are integrated into a pilot valve, and the pump port is
The assist pump 20 is connected via the relief valve 19, and the tank 17 is connected to the tank port.

Next, the operation will be described based on such a configuration. When the boom lever 6 is operated, the boom main valve 9 is passed through the boom pilot valve 10 of the boom control valve 4.
Is controlled to operate the boom cylinder 2, and the boom 52 is moved up and down with respect to the vehicle body 51. When the bucket lever 7 is operated, the bucket pilot valve 1 of the bucket control valve 5
The bucket main valve 11 is controlled via 2 to actuate the bucket cylinder 3 and the bucket 5 to the boom 52.
3 is looked up.

When the boom lever 6 is operated to the raised position,
The boom lever 6 is held in the raised position by an electromagnetic detent (not shown). After that, when the on / off type switch 16 of the boom control switch 8 is turned on while the bucket lever 7 is being held, the on / off type solenoid valve 15 is switched to the upper position in FIG. The rising pilot pressure to the main valve 9 is shut off, the boom main valve 9 is returned to the neutral position, the operation of the boom cylinder 2 is stopped, and the rising of the boom 52 is stopped. In this state, the on / off type switch 1
When 6 is turned off, the boom 52 is raised again. In other words, after operating the boom lever 6 to the raised position, by operating the on / off type switch 16 of the boom control switch 8 while holding the bucket lever 7, the boom 52 can be raised or stopped, and the boom 52 can be raised. You can control it. Therefore, while operating the bucket lever 7,
Since the rise of the boom 52 can be controlled, the scooping operation can be properly and easily performed.

Since it is not necessary to re-grip the bucket lever 7 to the boom lever 6, the operation is easy and the operator's fatigue is reduced. In addition, at the time of discharging work, it was often the case that the dump truck could be discharged without looking at the condition of the items to be handled and the packing style could not be adjusted, but since the operator is still holding the bucket lever 7, the items to be handled may be adjusted. At the same time, it is possible to release the boom 52, and at the same time, the boom 52 can be stopped from rising, if necessary, and the packing form can be adjusted.

Although the boom control valve 4 is a so-called pilot type having the boom main valve 9 and the boom pilot valve 10 for pilot-controlling the boom main valve 9 in the previous example, the boom control valve 4 is not limited to this, but is, for example, an electromagnetic type. Alternatively, the boom lever 6 may be directly controlled by a switch interlocking with the boom lever 6.
In this case, since the boom control switch 8 can be configured by the electromagnetic boom control valve 4 and the on / off type switch 16 connected to the raising solenoid thereof, the on / off type solenoid valve 15 can be omitted. In the previous example, the boom control switch 8 includes the on / off type solenoid valve 15 and the on / off type switch 16, but the boom control switch 8 is not limited to this. For example, the boom control valve 8 is provided between the boom main valve 9 and the boom pilot valve 10. It may be provided with a proportional solenoid valve provided to control the rising pilot pressure and a variable switch provided to the grip portion 14 of the bucket lever 7 to control the proportional solenoid valve. Although the work vehicle 50 is a bucket as a work tool in the above example, the work vehicle 50 is not limited to this and may be replaced with, for example, a fork or a dozer.

[0025]

As described above, according to the present invention,
The following excellent effects can be achieved. (1) A boom control that includes a boom cylinder, a bucket cylinder, a boom control valve, a bucket control valve, a boom lever, a bucket lever, and a boom control switch, and in particular, controls the boom control valve on the bucket lever to control boom raising. Since the switch is provided, it is possible to easily control the boom rise while operating the bucket lever. (2) Since the bucket lever is simply provided with the boom control switch for controlling the boom control valve to control the boom ascent, the structure is simple and the cost is low.
It can be easily applied to existing ones.

[Brief description of drawings]

FIG. 1 is a hydraulic circuit diagram showing a cargo handling operation device of the present invention.

FIG. 2 is a side view showing a work vehicle.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Cargo handling device, 2 ... Boom cylinder, 3 ... Bucket cylinder, 4 ... Boom control valve, 5 ... Bucket control valve, 6
... Boom lever, 7 ... Bucket lever, 8 ... Boom control switch, 9 ... Boom main valve, 10 ... Boom pilot valve, 11 ... Bucket main valve, 12 ... Bucket pilot valve, 13, 14 ... Grip, 15 ... On-off type Solenoid valve, 16 ... ON / OFF type switch, 17 ... Tank, 18 ...
Main pump, 19 ... Relief valve, 20 ... Assist pump, 50 ... Work vehicle, 51 ... Vehicle body, 52 ... Boom,
53 ... bucket, 54 ... bell crank, 55 ... push rod.

Claims (4)

[Claims] 1. A boom cylinder that raises and lowers a boom with respect to a vehicle body, a bucket cylinder that raises and lowers a bucket with respect to the boom, a boom control valve that controls the boom cylinder, and a bucket control valve that controls the bucket cylinder. It is composed of a boom lever that operates the boom control valve, a bucket lever that operates the bucket control valve, and a boom control switch that is provided on the bucket lever and controls the boom control valve to control the boom rise. The cargo handling control device. 2. The cargo handling operation device according to claim 1, wherein the boom control valve includes a boom main valve and a boom pilot valve for pilot-controlling the boom main valve. 3. A boom control switch is provided between a boom main valve and a boom pilot valve to control an ascending pilot pressure, and an on / off type solenoid valve is provided at a grip portion of a bucket lever. The on / off switch for controlling the cargo handling operation device according to claim 2. 4. A boom control switch is provided between a boom main valve and a boom pilot valve to control a rising pilot pressure, and a proportional solenoid valve is provided at a grip portion of a bucket lever. The cargo handling operating device according to claim 2, further comprising a variable switch for controlling the cargo handling operation.