JP2709344B2 - Control device for hydraulic ripper with impact device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a hydraulic ripper with an impact device, and more particularly, to a hydraulic circuit connecting a hydraulic actuator and a hydraulic pump with a hydraulic circuit according to an engine rotation condition. And a control device for switching.

[Conventional technology]

In the ripper method in which a hydraulic ripper is mounted on the rear part of the body of the bulldozer to perform rock excavation, a so-called impact device in which an impact device 8 is mounted on the ripper device 7 as shown in FIG. Hydraulic ripper is often used. In the hydraulic ripper with the impact device, in order to operate the lift cylinder 5 for controlling the vertical movement of the ripper device 7, the tilt cylinder 3 for controlling the excavation angle of the ripper shank 6, and the impact device 8 for applying an impact force to the ripper shank 6, This is performed by flowing the pressure oil sent from the hydraulic pump 109. Since these hydraulic circuits are formed in a parallel circuit, an impact force is applied to the ripper shank 6 by operating the lift / tilt operation lever 14 and the impact device operation lever 15 according to the working conditions while moving the vehicle forward. While the ripper device 7 is moved up and down to change the digging angle of the ripper shank 6 in various ways, the rock can be excavated and run forward.

[Problems to be solved by the invention]

In recent bulldozers, if the shoe 20 of the undercarriage device is kept in a slip state during the operation, the operation will continue to waste fuel and lead to abnormal wear of the undercarriage parts. In the case of a shoe slip, the rotation of the engine 21 is lowered to save fuel,
The aim is to maintain the durability of the suspension parts. When the hydraulic lipper with an impact device is mounted on a vehicle equipped with the shoe slip controller, the hydraulic lip with the impact device originally applies an impact force to the ripper shank in a hard rock area where shoe slip occurs. Although it is designed to crush the oil, the output from the hydraulic pump 109 is reduced to control the engine output to decrease during a shoe slip, and the lift cylinder 5, the tilt cylinder 3, and the impact device 8 are used at the same time. Alternatively, even when used alone, the number of impacts applied to the ripper shank 6 by the impact device 8 is reduced due to a decrease in the pressure oil sent to the impact device 8, which causes a problem that the rock crushing force is reduced. The present invention focuses on the above problem, and attaches two large and small hydraulic pumps, connects the small capacity pump and the impact device during normal work, and sets the hydraulic pump and hydraulic pressure so that the large capacity pump and the impact device communicate during shoe slip. It is an object of the present invention to provide a control device in which a pump switching valve is provided in a hydraulic circuit connecting actuators, and a required oil amount can always be secured for an impact device.

[Means for solving the problem]

In order to achieve the above object, according to the first aspect of the present invention, a parallel link is formed by a bracket (1), a beam (2), a tilt cylinder (3), and an arm (4), and a lift cylinder (5).
A hydraulic ripper with an impact device that performs up and down movement of the parallel link by expansion and contraction, and performs an impact on a head of a ripper shank 6 having a fulcrum on the beam 2 with an impact device 8 attached to the beam 2 to perform rock excavation. A hydraulic circuit 10 connecting the tilt cylinder 3, the lift cylinder 5 and the hydraulic pump 9, and a hydraulic circuit connecting the impact device 8 and the hydraulic pump 11.
A pump switching valve 13 is provided in the middle of 12, and the tilt cylinder 3,
A second aspect of the present invention is a control device for a hydraulic ripper with an impact device, characterized in that the connection state between the lift cylinder 5 and the impact device 8 and the hydraulic pumps 9 and 11 can be switched according to the rotation state of the engine. Item (2): The control device for the hydraulic ripper with the impact device according to the above (1), wherein the switching of the pump switching valve is performed manually, and (3) the switching of the pump switching valve and the operation of the impact device. The control device of the hydraulic ripper with the impact device according to claim (1), which automatically performs the control by a shoe slip detection signal, is provided.

(Operation)

According to the above configuration, at the time of rated rotation of the engine, the discharge oil of the large-capacity pump is sent to the lift cylinder and the tilt cylinder, and the discharge oil of the small-capacity pump is sent to the impact device so that an appropriate working speed can be obtained. Has become. When a shoe slip occurs, the engine speed is reduced because the operator controls to reduce the engine output.However, by manually or automatically switching the pump switching valve, the discharge oil of the large capacity pump is sent to the impact device. In spite of the decrease in the engine speed, the required flow rate is secured, the decrease in the excavating force due to the decrease in the engine speed is prevented, and the discharge amount of the small capacity pump is sent to the lift cylinder, the tilt cylinder, and the The vertical movement and the digging angle of the ripper shank can be adjusted.

〔Example〕

Hereinafter, an embodiment of a control device for a hydraulic ripper with an impact device according to the present invention will be described with reference to the drawings. FIG. 1 is a first embodiment of a control device for a hydraulic ripper with an impact device according to the present invention, and FIG. 2 is a second embodiment of a control device for a hydraulic ripper with an impact device according to the present invention.

A parallel link is constituted by a bracket 1, a beam 2, a tilt cylinder 3, and an arm 4 at a rear portion of the vehicle body of the bulldozer, and the parallel link is moved up and down by expansion and contraction of a lift cylinder 5 connected to the bracket 1 and the beam 2. , The hydraulic breaker 8 attached to the beam 2,
A hydraulic ripper with an impact device for applying an impact on the head of a ripper shank 6 having a fulcrum 6a is mounted. Engine 21
The hydraulic oil discharged from the large-capacity hydraulic pump 9 is sent to the tilt cylinder 3 and the lift cylinder 5 through the pump switching valve 13, and the hydraulic circuit 10 forms a parallel circuit. On the other hand, the discharge oil of the small capacity hydraulic pump 11 is a pump switching valve
It is sent to the hydraulic breaker 8 through the hydraulic circuit 12 through 13. When the tilt operation valve 3a, the lift operation valve 5a, the hydraulic breaker operation valve 8a, and the pump switching valve 13 are moved, the lift tilt operation lever 14, the hydraulic breaker operation lever 15, and the pump switching operation lever 17 are moved by the controller 16. Each solenoid valve is operated by passing a current. Next, the operation will be described. During a normal ripping operation, that is, when the engine 21 is rotating at a fixed rotation, the discharge oil of the large capacity pump 9 and the small capacity pump 11 is sent to the lift cylinder 5, the tilt cylinder 3, and the hydraulic breaker 8, In the simultaneous operation, the pump capacity is determined so that the hydraulic cylinder can be moved up and down by the lift cylinder, the digging angle of the ripper shank 6 can be adjusted by the tilt cylinder, and the number of impacts of the hydraulic breaker can be obtained at a speed suitable for the working conditions. I have.
In a hard rock area, when the shoe 20 under the suspension slips during work, the operator performs texel operation, so that the rotation speed of the engine 21 decreases, and the delivery amount of the hydraulic pump 11 decreases, and the delivery of the hydraulic pump 11 to the hydraulic breaker 8 decreases. The amount of oil decreases, the number of impacts by the hydraulic breaker decreases, and the crushing force weakens. However, when the operator moves the pump switching operation lever 17, the pump switching valve 13 is switched by an electric signal from the controller 16 and the large capacity hydraulic pump 9 is switched. The discharged oil is sent to the hydraulic breaker 8 and the discharged oil from the small-capacity hydraulic pump 11 is sent to the lift cylinder and the tilt cylinder, so that the hydraulic breaker 8 can secure the required flow rate regardless of the decrease in the engine speed. For,
The impact can be applied to the ripper shank head at the same frequency as the rated engine speed. Under working conditions in which a shoe slip occurs, the range of the vertical movement of the ripper device 7,
Alternatively, the digging angle adjustment amount of the ripper shank 6 is very small, and the required speed is sufficiently secured by the discharge amount of the small capacity hydraulic pump. In FIG. 2 showing the second embodiment, the structure is exactly the same as that of the first embodiment except that a shoe slip controller 18 is added and the pump switching operation lever 17 is deleted. Is the pump switching operation lever 17
Is operated by the operator, but in order to eliminate the time loss and trouble of operating the pump switching operation lever 17 after catching the decrease in the engine rotation by the shoe slip controller, the shoe slip controller 18 is operated. From the engine 21 and the controller 16 at the same time, lowering the engine speed, switching the pump switching valve and operating the hydraulic breaker at the same time, the most effective use of the hydraulic ripper with impact device Becomes possible.

〔The invention's effect〕

As described above, according to the present invention, at the time of normal work, when adjusting the digging angle of the ripper shank, the efficient operation speed is secured by the discharge oil of the large capacity pump, and the hydraulic breaker is used for the hydraulic breaker. The discharge oil of the small capacity pump can apply an impact force on the ripper shank head at the optimum frequency. In the event of a shoe slip, if a shock is not applied by switching the pump switching valve, the impact can be applied to the hard rock which is difficult to break, regardless of the decrease in engine speed, without reducing the number of shocks and on the ripper shank head. Is improved. In particular, in the automated second embodiment in which a signal from the shoe slip controller issues a command to lower the engine speed, a command to switch the pump switching valve, and a command to operate the hydraulic breaker, the necessity of applying a shock when a shoe slip occurs is automatically determined. In addition, the hydraulic pump is switched, and the flow rate required for impact is secured regardless of the decrease in engine speed, and digging is performed while applying an impact force on the ripper shank head. Since the method is used, the operator does not need to judge whether or not to use the hydraulic breaker, thereby improving work efficiency, saving fuel, and improving durability of underbody parts.

[Brief description of the drawings]

FIG. 1 is a first embodiment of a control device for a hydraulic ripper with an impact device based on the embodiment of the present invention, and FIG. 2 is a second embodiment of a control device for a hydraulic ripper with an impact device based on the embodiment of the present invention. The figure shows a control device for a hydraulic ripper with an impact device according to the prior art. 3 ... Tilt cylinder, 5 ... Shift cylinder, 6 ...
Ripper shank, 8: Hydraulic breaker, 9: Large capacity hydraulic pump, 10: Small capacity hydraulic pump, 13: Pump switching valve

Claims (3)

(57) [Claims] A bracket, a beam, a tilt cylinder, and an arm constitute a parallel link.
A hydraulic ripper with an impact device that performs up and down movement of the parallel link due to expansion and contraction of the rocker, and performs an impact on the head of a ripper shank 6 having a fulcrum on the beam 2 with an impact device 8 attached to the beam 2 to perform rock excavation. In the control device, at the time of non-shoe slip, the hydraulic oil supply path 10 to the tilt cylinder 3 and the lift cylinder 5 is connected to the first hydraulic pump 9, and the hydraulic oil supply path 12 to the impact device 8 is connected to the second hydraulic pump 11. The tilt cylinder 3 due to the occurrence of shoe slip
A pump switching valve 13 for switching the hydraulic oil supply path 10 to the lift cylinder 5 so as to be connected to the second hydraulic pump 11 and the hydraulic oil supply path 12 to the impact device 8 to be connected to the first hydraulic pump 9 is provided. A control device for a hydraulic ripper with an impact device. 2. The method according to claim 1, wherein the first hydraulic pump 9 is a large-capacity pump, the second hydraulic pump 11 is a small-capacity pump, and the pump switching valve 13 has A control device for a hydraulic ripper with an impact device, characterized in that the control device is a manual switching valve that switches by detecting the occurrence with a sense. 3. The method according to claim 1, wherein the first hydraulic pump 9 is a large capacity pump, the second hydraulic pump 11 is a small capacity pump, and the pump switching valve 13 is interlocked with shoe slip control. A control device for a hydraulic ripper with an impact device, characterized in that the control device is an automatic switching valve that can be switched by switching.