JPH074132Y2 - Hydraulic breaker operating device - Google Patents

Description

[Detailed Description of the Invention] Industrial field of application The present invention, when a hydraulic breaker is attached to a working machine having a hydraulic source for operating various working devices to perform crushing work, an appropriate amount of oil flowing into the hydraulic breaker. The present invention relates to an operating device of a hydraulic breaker that automatically obtains.

2. Description of the Related Art The optimum amount of inflow oil required for a hydraulic breaker is determined depending on its type.When the amount of inflow oil is less than the specified amount, the operation will be slow and the crushing capacity will decrease and the work efficiency will decrease. Needless to say, however, if an amount of oil more than the specified amount flows in, troubles such as a failure of the hydraulic breaker, an abnormal rise in the temperature of the hydraulic oil, and overheating of the engine will be caused.

Therefore, when the hydraulic breaker is mounted on a work machine that has a hydraulic source for operating various working devices and the machine is operated using the large-capacity hydraulic source, the amount of inflow oil must be the specified amount in advance. It must be adjusted and crushed so that it does not exceed the limit.

For example, in front of the machine body 22 of the hydraulic excavator shown in FIG. 6,
When the boom 23 and the arm 24 are pivotally supported, the hydraulic breaker 11 is attached to the tip of the arm 24, and the actuators 25, 26, 27 are expanded and contracted to the crushing work posture, the rock 28 which is the crushing target is first In order to position the tip tool of the hydraulic breaker 11, the actuator 25 is expanded and contracted to move the boom 23 up and down, and the actuator 26 is expanded and contracted to move the arm 24 back and forth.
The actuator 27 is expanded and contracted to rotate the tip tool of the hydraulic breaker 11 back and forth as appropriate, to position the tool, and then crushing is started. Then, when the crushing of the rock 28 is completed, the actuator is prepared in preparation for crushing the next rock 29.
A method of advancing the crushing work by the same means as described above, such as expanding and contracting 25, 26, 27 and moving the machine body 22, is adopted. During this time, moving the machine body 22, rotating the boom 23, the arm 24, and the hydraulic breaker 11 as quickly as possible contributes to improving the efficiency of the crushing work.
It is operated so that the amount of oil discharged from the main pump, which serves as a hydraulic pressure source, is maximized.On the other hand, when the hydraulic breaker 11 is activated and crushed, the amount of inflow oil specified by the installed hydraulic breaker 11 is used. You must be able to get the number of hits.

However, in general, the hydraulic power source provided in the machine body that can withstand the weight of the mounted hydraulic breaker, the desired work range, the impact reaction force, etc. has a capacity far exceeding the specified inflow oil amount of the hydraulic breaker. Depending on the configuration of the hydraulic circuit, there may be a method in which when a single actuator is operated, the pressure oil discharged from multiple main pumps merges, or the oil is supplied by increasing the amount to match the engine capacity. When the hydraulic breaker is operated independently, the inflow oil amount exceeds the specified oil amount. As a result, not only the efficiency of the hydraulic breaker is lowered, but also the above-mentioned troubles occur.

In order to prevent such a situation, when the hydraulic breaker is conventionally operated, the accelerator lever 31 shown in FIG. 4 is pulled back to the intermediate position, the engine speed is reduced, and the discharge oil amount of the main pump is reduced. Although the impact starts, the control stand 30 can be used as a guide for obtaining the discharge oil volume of the main pump suitable for the installed hydraulic breaker.
A caution plate 32 as shown in FIG. 5 is attached to the side of the upper accelerator lever 31, and the accelerator lever 31 is always set at the arrow position of the caution plate 32 when the hydraulic breaker is activated. Is obliged to do that.

Problem to be solved by the invention The capacity of the hydraulic source of the working machine, that is, the amount of oil discharged from the main pump is generally large compared to the prescribed amount of oil required by the hydraulic breaker to be installed. Therefore, the accelerator lever 31 must be set to an intermediate position such as the arrow position of the caution plate 32 described above only when the hydraulic breaker is operated. Further, in the crushing work by the hydraulic breaker, as described in the explanation of FIG. 6,
Positioning and crushing are not repeated for a long time, but positioning and crushing are repeated alternately for a short time.When an actuator other than a hydraulic breaker that requires a large amount of pressure oil is operated, the accelerator lever is set to the maximum rotation position and crushed. Occasionally, the accelerator lever must be moved to the intermediate position and operated each time.

In this way, it is a great burden for the driver to operate the accelerator lever frequently and at the designated position at the same time as operating the hydraulic switching valve for actuating and stopping the hydraulic breaker and the actuator necessary for positioning. Therefore, there is a problem in that the crushing work tends to continue with the accelerator lever at the maximum engine rotation position, either intentionally or by mistake, resulting in a serious accident of the hydraulic breaker and hydraulic system. It was

Means for solving the problems a. In the operating device of the hydraulic breaker of the present invention, the boom, the arm, and the hydraulic breaker are sequentially connected to the front part of the machine body by actuators so as to be rotatable in the front-rear direction,
In addition, a hydraulic switching valve group consisting of a hydraulic pilot type hydraulic switching valve for the hydraulic breaker and a hydraulic switching valve for actuators other than the hydraulic breaker is provided inside the machine, and pressure oil from the main pump that is driven by the engine is supplied. In a working machine in which the hydraulic breaker, the actuator and the like are supplied through the above hydraulic switching valves, With the tip of the control lever for the engine governor,
The accelerator lever is connected via a connecting device with a built-in spring, and the biasing force of the spring is applied so that the control lever is pulled in the direction in which the engine rotation increases, and the accelerator lever adjustment position holding force. Set smaller than Also, a cylinder is fixedly provided near the control lever, and between the cylinder and the control lever,
A lever having a fulcrum at the center is provided so that one end of the lever is brought into contact with the rod tip when the cylinder is extended, and the other end of the lever and the tip of the control lever are connected via a rod. Connect, d. Further, the bottom side oil chamber of the cylinder is connected to the pilot line of the hydraulic breaker switching valve, and the cylinder is operated by the pilot pressure for the hydraulic breaker, so that the control lever rotates the engine through the lever and the rod. It is designed to rotate in the direction that lowers the.

Action With the accelerator lever set to the position where the maximum engine speed can be obtained, if the pilot pressure is applied to the pilot oil chamber of the hydraulic switching valve via the pilot line in order to operate the hydraulic breaker, At the same time, the pressure acts on the oil chamber of the cylinder through the branched pilot line, so that the cylinder operates and a point on the rod or link that interlocks with the control lever is resisted against the biasing force of the spring in the coupling device. Since the engine is pushed back in the direction of decreasing its rotational speed, the amount of oil discharged from the main pump driven by the engine is reduced to an amount suitable for the operation of the hydraulic breaker.

Also, when the hydraulic breaker operation is stopped, pilot pressure does not act on the oil chamber of the cylinder, and the engine control lever returns to the position initially set by the accelerator lever due to the biasing force of the spring in the coupling device. The engine speed is recovered, the amount of oil discharged from the main pump is increased, and actuators other than the hydraulic breaker can be operated quickly.

Embodiment An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a system diagram of the hydraulic pressure and mechanism of the embodiment according to the present invention. Here, a system of a single hydraulic pump and a hydraulic switching valve group is shown, but in a practical machine, another hydraulic pump is used. And a hydraulic pressure switching valve group are arranged side by side to operate various actuators.

In the figure, 1 and 2 are the same engine (not shown,
The same applies hereinafter) and a main pump, which is a pilot pump mainly serving as a hydraulic pressure source for the operating system, and the hydraulic fluid discharged from the main pump 1 passes through the pipeline 3 and has a hydraulic switching valve group including hydraulic switching valves 4 and 5. It flows into A, and its return oil is pipe 12
Return to tank 13 via.

When pilot pressure is applied to the pilot oil chamber a or b of the hydraulic pressure switching valve 4, the pressure oil flowing into the hydraulic pressure switching valve 4 is switched, the actuator 8 is operated through the pipeline 6 or 7, and the pilot of the hydraulic pressure switching valve 5 is operated. When the pilot pressure acts on the oil chamber c, the hydraulic pressure switching valve 5 is switched, and the pressure oil is transferred to the pipe line 9.
The hydraulic breaker 11 is activated through the
Return to the tank 13 via 0 and the conduit 12. In addition, hydraulic breaker 1
In 1, the pressure oil inlet and outlet are fixed, and there is no need to reverse the pressure oil, so the pilot oil chamber d of the hydraulic pressure switching valve 5 is always communicated with the tank 13.

Reference numeral 15 is a pilot valve for generating a pilot pressure for switching the hydraulic pressure switching valve 5, the pressure oil of a constant pressure from the pilot pump 2 is supplied through a pipe line 14, and its outlet port is a pilot oil chamber c of the hydraulic pressure switching valve 5. Is connected to the tank 13 by supplying a pilot pressure corresponding to the operation amount of the pedal 18 to the oil chamber c, and when the pedal 18 is opened, the conduit 14 is closed and the pilot conduit 16 is connected to the tank 13. Let The pilot line 16 is branched in the middle to form a pilot line 17 connected to the oil chamber g of the cylinder 19.

Reference numeral 20 denotes a lever which is connected to one end of a rod 21 for increasing / decreasing the engine speed and rotates with the movement of the rod 21. When the rod 21 moves in the direction of arrow B in the figure, the engine speed increases, and The maximum rotation speed is the maximum rotation speed, and the minimum rotation speed is the set minimum rotation speed when moving in the direction of arrow C. The other end of the rod 21 is connected to the control lever 33 of the engine.
Is also connected to the accelerator lever 31 via a connecting device 34. This connecting device 34 is as shown in the sectional view of FIG.
It is composed of a spring case 35, an adjusting rod 36, a spring 37, a rod 38, etc., and the bottom of the spring case 35 is against the external force in the direction of pushing the pin hole e of the adjusting rod 36 end and the pin hole f of the rod 38 end. And the spring receiving portion fixed to the other end of the rod 38 come into contact with each other, and the distance between the pin holes e and f does not decrease, but if the force in the pull-out direction is larger than the biasing force of the spring 37, the rod 38 will gradually It is pulled out from the spring case 35, and the distance between the pin holes e and f is extended.The urging force of the spring 37 is larger than the reaction force of the control lever 33 at the time of maximum engine rotation, and the accelerator lever 31 It is designed to be smaller than the force that holds one's position.

Further, the mounting position of the cylinder 19 comes into contact with one point on the lever 20 when the cylinder 19 extends, and resists the biasing force of the spring 37 in the coupling device 34 to move the control lever 33 through the rod 21. The lever 20 is mounted so as to be rotated to the position of the illustrated lever 20 'until the engine speed reaches a predetermined value lower than the maximum engine speed.

FIG. 3 is a diagram showing the relationship of the discharge oil amount Q with respect to the engine speed, that is, the number of revolutions N of the main pump 1. When the normal working actuator is operated, the rod 21
Is fully moved in the direction of arrow B, the engine speed is Nm at the position of the lever 20, and the amount of oil discharged from the main pump 1 at that time is Qm, but the engine speed is lower than Nm.
This shows the characteristic that the amount of discharged oil is reduced to Qb when it becomes Nb.

Next, the configuration of the operating device of the hydraulic breaker 11 of the present invention will be described first.
Referring to FIG. 3 to FIG. In the present invention, the tip end of the control lever 33 for the engine governor and the accelerator lever 31 are connected via the connecting device 34 having the spring 37 built therein, and the urging force of the spring 37 is increased in the engine rotation direction. Control lever 33 (in the direction of arrow D)
Is set to be smaller than the adjustment position holding force of the accelerator lever 31 while causing it to be pulled. A cylinder 19 is fixedly provided near the control lever 33, and between the cylinder 19 and the control lever 33,
A lever 20 having a fulcrum is provided at the center, and the one end of the lever 20 is arranged so that the tip of the rod abuts when the cylinder (19) extends, and the other end of the lever 20 and the tip of the control lever 33. The part was connected via a rod 21. In addition, the bottom side oil chamber of the cylinder 19 and the pilot line 16 of the hydraulic pressure switching valve 5 for the hydraulic breaker (11) are
The cylinder 19 is connected through the pilot line 17.
Is operated by the pilot pressure for the hydraulic switching valve (5), so that the control lever 33 rotates via the lever 20 and the rod 21 in the direction in which the engine rotation is reduced (the direction of arrow C). did. Next, the operation of the embodiment of the present invention will be described.

Attach the hydraulic breaker 11 and start crushing rocks,
Or, in order to move or position the machine to move to the next crushing, when operating the actuators such as the boom, arm, and breaker posture maintenance, move the accelerator lever 31 (Fig. 4) rod 21 in the direction of arrow B. When the engine speed N is fully moved to a predetermined maximum speed Nm, the discharge oil amount Q of the main pump 1 becomes the maximum discharge amount Qm and flows into the hydraulic pressure switching valve group A. By operating the switching valve 4 or a hydraulic switching valve (not shown) other than the hydraulic switching valve 5 for operating the hydraulic breaker 11, it is possible to quickly move and position the machine body.

When the pedal 18 is stepped on from this state and the pressure oil of the pilot pump 2 is made into pilot pressure by the action of the pilot valve 15 and is guided to the pilot oil chamber c via the pilot pipe line 16, the hydraulic switching valve 5 switches and the main pump The pressure oil of No. 1 flows into the hydraulic breaker 11 through the hydraulic switching valve 5 and the pipe line 9 to operate the hydraulic breaker. At the same time, the pilot pressure of the pilot pipe line 16 passes through the pilot pipe line 17 of the cylinder 19. Acting on the oil chamber g, the cylinder 19 is extended, the rod tip of which rotates the lever 20 from the position shown in FIG. 20 to the position shown at 20 ', so that the spring 37 in the coupling device 34 is attached. Along with the spring case 35, the adjusting rod 36, and the control lever 33, the rod 21 is set to the first position against the power.
Pull back in the direction of arrow C in the figure. At this time, the accelerator lever 31
Since the force for holding its own position is larger than the biasing force of the spring 37, the accelerator lever 31 holds the original set position.

As a result of the above operation, the engine speed N is automatically reduced from Nm shown in FIG. 3 to Nb without operating the accelerator lever 31 at all, and the discharge oil amount of the main pump 1 is reduced. Since Q is reduced from Qm to Qb, the hydraulic breaker 11 is operated with an appropriate inflow oil amount Qb.

In the above device, in order to realize the engine speed Nb that can obtain the discharge oil amount Qb suitable for the operation of the hydraulic breaker 11, the capacity of the main pump mounted on the hydraulic excavator and the link attached to the engine control device are required. It can be applied to any machine by appropriately selecting the stroke of the cylinder 19 that fits the lever, rod, etc., its installation position, the connecting device, and the like.

Next, if the hydraulic breaker 11 is stopped,
Since the oil chamber g of 19 communicates with the tank 13 via the pilot lines 17 and 16 and the pilot valve 15, the extension force of the cylinder 19 disappears, and as a result, the rod 21 is urged by the spring 37 to cause the spring case 35 to move. , The adjusting rod 36, the control lever 33, and the lever 20 move in the direction of arrow C, and the engine speed N returns to the original set speed Nm.

In the above embodiments, the rod tip of the cylinder 19 abuts the lever 20 to limit the movement of the rod 21, but the lever 20 is not necessarily provided, and the cylinder 20
It is needless to say that the movement of the interlocking member with the rotation angle or rotation of the control lever 33 may be limited when 19 is extended or contracted.

Effects of the Invention When the hydraulic breaker is mounted on a hydraulic work machine, if the operating device of the present invention is provided, the accelerator lever is set so as to operate quickly when an actuator other than the hydraulic breaker is activated. Even if the hydraulic breaker is activated, the engine speed will automatically decrease, and the amount of oil discharged from the main pump will be reduced to an amount suitable for operating the hydraulic breaker steadily. Again, the engine speed automatically returns to the original state, so there are no problems such as damage during hydraulic breaker operation, oil temperature rise, engine overheating, etc. There is no need to adjust the accelerator lever each time when using the actuator or when using other actuators, no erroneous operation occurs, and operation is simplified. The efficiency is high, and it is possible to concentrate on operating the work equipment at all times, which leads to safe work.

[Brief description of drawings]

FIG. 1 is a hydraulic and mechanical system diagram showing the configuration of the present invention,
FIG. 2 is a sectional view showing the structure of the coupling device in FIG.
Fig. 3 is a diagram showing the characteristics of the main pump, Fig. 4 is a perspective view showing the operation of the accelerator lever, Fig. 5 is a front view showing an example of a caution plate, and Fig. 6 is a hydraulic breaker for a hydraulic excavator. It is a side view which shows the state at the time of mounting and performing a crushing operation. 11 …… hydraulic breaker 19 …… cylinder 20 …… lever 21 …… rod 30 …… control stand 31 …… accelerator lever 33 …… control lever 34 …… coupling device

Claims (1)

[Scope of utility model registration request] 1. A boom, an arm, and a hydraulic breaker are sequentially connected to a front portion of the machine body by actuators so as to be rotatable in the front-rear direction, and a hydraulic pilot type hydraulic switching valve and a hydraulic breaker for the hydraulic breaker are provided inside the machine body. Other than the above, a hydraulic pressure switching valve group composed of hydraulic pressure switching valves for actuators is provided, and pressure oil from the main pump rotated by the engine drive is supplied to the hydraulic breakers, actuators, etc. via the above hydraulic pressure switching valves. In the working machine, the tip of the control lever for the engine governor and the accelerator lever are connected via a connecting device that has a built-in spring, and the urging force of the spring is controlled in the direction in which the engine rotation increases. Force the accelerator lever and adjust the accelerator lever. It is set smaller than the position holding force, and a cylinder is fixedly provided near the control lever, a lever having a fulcrum in the center is provided between the cylinder and the control lever, and one end of the lever is When the cylinder is extended, the rod tip is arranged so that it abuts, the other end of the lever and the tip of the control lever are connected via a rod, and the bottom oil chamber of the cylinder and the hydraulic breaker switch are connected. The control pipe is made to communicate with the pilot line of the valve and the cylinder is operated by the pilot pressure for the hydraulic breaker, so that the control lever is rotated in the direction to reduce the engine rotation through the lever and the rod. Characteristic hydraulic breaker operating device.