JPH04312679A - Crushing device - Google Patents

Abstract

PURPOSE:To simplify operation by an operator, to reduce a piping cost and to promote work efficiency. CONSTITUTION:A crushing device is equipped with a crushing mechanism opening, closing and driving a pair of crushing arms with an automatic return type single acting cylinder 15 and a hydraulic motor 9. An open center type selector valve 26 having four ports and three positions is laid among the crushing mechanism, the hydraulic motor 9, a pump 24 and a tank 25, the first load port P1 is connected to a passage 27 to the automatic return type single acting cylinder 15, and the second load port P2 is connected to a passage 28 to the hydraulic motor 9. In addition, a fluid outlet 29 side of the hydraulic motor 9 is returned and connected to a fluid inlet 31 side of the motor through a relief valve 30 and, at the same time, it is connected to the passage 27 to the automatic return type single acting cylinder 15 through a check valve 32.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a crushing device for crushing concrete structures and the like by opening and closing a crushing arm equipped with crushing blades in the shape of scissors.

0002

[Prior art] This type of crushing device (Japanese Patent Application Laid-Open No. 1-2146
Typical crushing mechanism 1 in JP-A No. 69, JP-A-63-156168, JP-A-62-63768)
As schematically shown in Fig. 7, the shaft 3,
A pair of crushing arms 4, 4 rotatably supported at 3,
It has a structure that can be opened and closed by a hydraulic cylinder 5 fixed to the side plates 2, 2, and is attached to a rotating plate 7 of a bracket 6 at the tip of a boom of a power shovel or the like. Crush arm 4, 4
has crushing blades 8, 8 facing each other inside, and the rotary plate 7 is driven and rotated by a hydraulic motor 9 fixed to the boom side.

During the crushing work, the operator moves the power shovel or the like to bring the crushing mechanism 1 at the tip of the boom closer to the part to be crushed of the structure, and presses the operating lever 1 for the hydraulic cylinder.
0 manually. Then, the switching valve 11 (usually a closed center type with 4 ports and 3 positions) that responds to the lever 10 supplies hydraulic oil from the pump to the hydraulic cylinder 5, shuts it off, and releases it to the tank, and the crushing arms 4 open and close. When it is closed, the crushing blades 8, 8 compress and crush the portion to be crushed.

[0004] At this time, the angle that the opening and closing surfaces of the crushing arms 4, 4 make with respect to the reference plane (horizontal plane or vertical plane) is adjusted depending on the condition of the part to be crushed. In other words, when the part to be crushed changes from a column to a floor plate, or when it is thought that the work efficiency will be improved by rotating the opening and closing surfaces of the crushing arms 4, 4 even in the same part to be crushed, the above-mentioned hydraulic motor 9 Operation lever 1
A switching valve 13 (normally,
A hydraulic motor 9 (a closed center type with 4 ports and 3 positions) is driven to rotate the crushing mechanism 1 relative to the boom.

Once the crushing of one location is completed, the crushing arms 4, 4 are moved to the next crushing location.
The area around the crushing arm 4 is often created by the current crushing operation, and usually the crushing arm 4 is used to move the crushing mechanism 1.
There is no need to wait for 4 to open completely. Therefore, in order to improve efficiency, it is possible to move the boom while operating the crushing arms 4, 4 in the opening direction and rotating the opening/closing surfaces of the crushing arms 4, 4 in accordance with the next part to be crushed. It will be done.

However, in order to perform the above operation while adjusting the angle of the opening/closing surfaces of the crushing arms 4, 4, in addition to operating the boom movement, the operating lever 10 of the hydraulic cylinder 5 and the operating lever 12 of the hydraulic motor 9 must be slightly moved. Operations must be performed on time. Moreover, since this process is often repeated, this operation is very complicated for the operator and requires a certain degree of skill.

Of course, after crushing one place, the crushing arm 4
, 4 may be sequentially crushed without adjusting the opening/closing surface angles. In this case, it is convenient to be able to operate only the hydraulic cylinder 5 independently of the hydraulic motor 9.

Furthermore, since the hydraulic cylinder 5 and the hydraulic motor 9 are each driven by two independent hydraulic circuits, there are two high-pressure pipes 14 for each system, a total of four high-pressure pipes 14, and at least one for each system. A total of two switching valves 11 and 13 are required, one for each.

[0009] However, these high-pressure pipes 14 are inherently expensive, and they also need to be connected to the hydraulic pump 15 and switching valves 11, 13 (operating parts) in the mechanical part of the power excavator through the boom to reach the above-mentioned actuator. Therefore, a long pipe is required, and in addition, at least two switching valves are required, and the installation of four pipes in two systems increases the piping cost.

0010

SUMMARY OF THE INVENTION An object of the present invention is to provide a crushing device that is easy to operate by an operator, has low piping costs, and has high working efficiency.

[0011]

[Means for Solving the Problem] A pair of crushing arms are connected by an automatic return type single-acting cylinder having a return means, and when the cylinder is driven by pressurized fluid, the pair of crushing arms can be opened and closed so as to be closed. Equipped with a crushing mechanism. It has a hydraulic motor that operates on the same pressurized fluid. 4 between the above crushing mechanism and hydraulic motor and pump and tank.
Interpose an open center type switching valve with port 3 position. A first load port of the switching valve is connected to a flow path to the self-returning single-acting cylinder, and a second load port is connected to a flow path to the hydraulic motor. Furthermore, the fluid outlet side of the hydraulic motor is connected back to the fluid inlet side of the motor via a relief valve, and also connected to the flow path to the automatic return type single-acting cylinder via a check valve. Another actuator may be connected to the second load port in the switching valve. The above-mentioned 4-port, 3-position open center type switching valve may be replaced with a 4-port, 3-position, closed center type switching valve that has the same function by adding a pilot valve.

0012

[Operation] The self-returning single-acting cylinder closes the crushing arm with pressurized fluid and crushes the structure. After crushing, it automatically returns by connecting to the drain and opens the crushing arm.

[0013] In this specification, the term "drain" is used to mean a storage location for working fluid at atmospheric pressure, such as a tank in a hydraulic circuit.

In the first position [A], the 4-port 3-position open center type switching valve connects and drives the pump to the self-returning single-acting cylinder, and drains the pressurized fluid inlet of the other actuator. In the second position [D], the flow path of the cylinder and the pressurized fluid inlet of the actuator are connected to the drain to open the crushing arm without changing the angle of its opening/closing surface, and in the third position [B] ], the flow path of the cylinder is connected to the drain to maintain the collapse arm in the opening state or in the open state, and a pump is connected to the pressurized fluid inlet of the other actuator to drive it. When the other actuator described above is a hydraulic motor for rotating the crushing mechanism, the angle of the crushing arm opening/closing surface is adjusted.

A 4-port, 3-position, closed-center switching valve with a pilot valve performs the same function as the 4-port, 3-position, open-center switching valve described above.

The pilot valve itself operates when the 4-port, 3-position closed center type switching valve is in the second position [E] and disconnects the automatic return type single acting cylinder and the other actuator from the pump and drain. , these are connected together to the drain to open the crushing arm without changing the angle of its opening/closing surface.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 2 to 4 show a bracket 6 attached to the tip of a boom of a power shovel and a crushing mechanism 1 attached to the bracket via a rotating plate 7.

In the crushing mechanism 1, a pair of crushing arms 4, 4 are rotatably supported by shafts 3, 3 on both side plates 2, 2, and the base side thereof is fixed to the base of the same side plates 2, 2. Cylinder 16 of spring return type single acting cylinder (hydraulic type...abbreviated as single acting cylinder) 15 as an automatic return type single acting cylinder
and is coupled to one end of the piston 17 so that it can be opened and closed. The single-acting cylinder 15 has a return spring 18 therein, and hydraulic oil enters and exits through one entrance and exit port 19. The return spring 18 always keeps the piston 17 in its original position (
The piston 17 is biased to return to the retracted position of the single-acting cylinder 15, and is shown in the extended state in FIG. 2, returning the piston 17 to its original position. Reference numeral 8 is a crushing blade, and crushing arm 4,
4 on the opposing surface of the distal end side.

The bracket 6 includes a rotary plate 7 that rotates about an axis a in the front-rear direction and a hydraulic motor 9 fixed to the bracket 6. The rotating plate 7 is substantially an annular internal gear as shown in FIG.
0, and a small gear 21 fixed to the output shaft of the hydraulic motor 9 meshes with this. The bases of the side plates 2, 2 of the crushing mechanism 1 are attached to the rotating plate 7 with bolts 22. Reference numeral 23 is a valve unit of a relief and check valve (described later) attached to the hydraulic motor 9, and is fixed adjacent to the hydraulic motor 9.

FIG. 1 shows a hydraulic circuit for controlling the single acting cylinder 15 and the hydraulic motor 9, which is combined with the crushing mechanism 1 to form a crushing device. This hydraulic circuit includes a 4-port, 3-position open center type switching valve 26 (hereinafter simply referred to as a switching valve) arranged between a single-acting cylinder 15, a hydraulic motor 9, a pump 24, and a tank 25 (drain). First load port P1 of switching valve 26
is connected to the conduit 27 to the single-acting cylinder 15, the second load port P2 is connected to the conduit 28 to the hydraulic motor 9, and further,
The fluid outlet 29 side of the hydraulic motor 9 is connected to the fluid inlet 31 side of the motor 9 via a relief valve 30, and the pipe line 2 is connected to the single acting cylinder 15 via a check valve 32.
7 (which may be a flow path that does not constitute a pipe).

Reference numeral 33 is an operating lever that moves the switching valve 26 to the first position [A], second position [D], and third position [B].
This is for switching to three positions. Further, the relief valve 30 and the check valve 32 are formed in the integrated valve unit 23 as described above.

When the switching valve 26 is set to the first position [A] using the operating lever 33, high-pressure hydraulic oil from the pump 25 enters the single-acting cylinder 15 through the pipe 27, compresses the return spring 18, and releases the piston. Push out 16. This results in
The crushing arms 4,4 are closed and the construct is crushed. On the other hand, since high pressure hydraulic oil is not supplied to the hydraulic motor 9,
The rotating plate 7 is not rotated, and the angle of the opening/closing surface formed by the crushing arms 4, 4 is not changed.

However, when the crushing arms 4, 4 close, the crushing mechanism 1 is passively rotated by the reaction received from the crushed portion, and the hydraulic motor 9 is rotated to the left (positive) in FIG. Although the motor fluid outlet 29 side circuit may be at high pressure, this circuit is connected to the tank 24 via a relief valve 30 to relieve excess pressure.

When the switching valve 26 is set to the second position [B], the hydraulic oil in the single acting cylinder 15 returns to the tank 25, and the return spring 18 returns the piston 16 to its original position. Therefore, the crushing arms 4, 4 of the crushing mechanism 1 open. Furthermore, since the switching valve 26 is a center open type, the inlet 31 side of the hydraulic motor 9 is also connected to the tank 25 in the same manner as above, and the hydraulic motor 9 does not rotate.
Similarly to the above, the opening/closing surface angles of the crushing arms 4, 4 do not change.

Therefore, if you wish to continue crushing without adjusting the opening/closing surface angles of the crushing arms 4, 4, repeat the process of returning the switching valve 26 with the operating lever 33 to the above-mentioned first state [A]. If you wish to adjust the above-mentioned opening/closing surface angle, advance the switching valve 26 to the third state [B
].

Note that after crushing by the crushing arms 4, 4, a space is created around the crushing arms 4, 4, so while opening the crushing arms 4, 4 with the switching valve 26 in the second position [D], That is, as in the conventional case, the crushing mechanism 1 can be moved to the next crushing location by moving the boom without waiting for the boom to fully open.

When the switching valve 26 is set to the third position [B], the single-acting cylinder 15 is connected to the tank 25, and the hydraulic motor 9 is supplied with high-pressure hydraulic oil, so that the crushing arm 4
, 4 remain open, and the angle of their opening/closing surfaces is changed. Note that the outlet 29 side of the hydraulic motor 9 is connected to the tank 25 through a check valve 32 and a conduit 27 of the single acting cylinder 15.

That is, the operator can open and close the crushing arms 4, 4 and adjust the angle of the opening/closing surface, which conventionally used two operating levers 10, 12 (FIG. 7) and two switching valves 11, 13, using one operating lever 32, This can be done with one switching valve 26. In addition, high-pressure piping (pipe line 2
7, 28...2 pieces (longer along the boom) are sufficient.

FIG. 5 shows a second embodiment of the hydraulic circuit, in which the switching valve 26 is of a center open type with 4 ports and 3 positions. This embodiment differs from the embodiment described above in that the outlet 29 of the hydraulic motor 9 is returned directly to the tank 25 via a return line (flow path) 34 . In this case, the pipe line 34 is replaced by the pipe lines 27 and 28.
Similarly, it is a long piece that runs along the boom, but because it is a return pipe, the internal hydraulic pressure is small and a so-called rubber hose can be used, which is inexpensive and does not significantly increase piping costs. Everything else is the same, and the opening/closing of the crushing arms 4, 4 and the drive of the hydraulic motor 9 can be controlled with a single operating lever 33.

FIG. 6 shows a third embodiment of the above hydraulic circuit, in which the 4-port, 3-position open center type switching valve 26 in the embodiment of FIG. 5 is replaced by a 4-port, 3-position closed center type switching valve 35 The difference is that the pilot valve 36 is replaced with a pilot valve 36 driven by pilot pressure related to its operation.

Note that this replacement is also possible in the embodiment shown in FIG.

The pilot valve 36 has three ports on the first to third load sides (P1 to P3), a first position where all three ports on the load side are directly connected to the tank 25, and a first load port P.
1 to the pump port P of the pilot valve 36, a second load port P2 to the tank port R, and a second position in which the third load port P3 is closed. This is a 5-port, 2-position automatic return type pilot valve in which the second position is moved by pilot pressure.

The switching valve 35 and pilot valve 36 are as follows:
The first load side port P1 of the switching valve 35 is connected to the pump port P of the pilot valve 36 through a first passage 37, and the other side is connected to the tank port R through a second passage 38. Further, pilot flow paths 39 and 40 are taken out from the first and second flow paths 37 and 38, respectively, and check valves 41 and 42 are provided respectively, and the pressure in these flow paths 39 and 40 is controlled by the valve of the pilot valve. The first load port P1 of the pilot valve 36 is connected to the pipe line 27 to the single acting cylinder 15, and the second load port P2 is connected to the pipe line 28 to the hydraulic motor 9. ing. Reference numeral 33 is an operating lever for the switching valve 35.

When the switching valve 35 is set to the first state [A] by the operation lever 33, the pressure in the first flow path 37 increases, so that the pilot valve 36 is moved through the pilot flow path 40.
switches to the second movement position. Therefore, the high pressure hydraulic oil from the pump 24 is communicated to the single acting cylinder 15, the crushing arms 4, 4 are closed, and crushing is performed. On the other hand, hydraulic motor 9
are connected to the tank 25, and the angles of the opening and closing surfaces of the crushing arms 4, 4 do not change.

However, when the crushing arms 4, 4 are bitten,
When the crushing mechanism 1 is passively rotated depending on the angle of its opening/closing surface and the crushing location, the hydraulic oil inlet 3 of the hydraulic motor 9
1 and the outlet 29 are directly connected to the tank 25, this rotation is performed smoothly without exerting excessive force on the hydraulic motor 9, the rotating plate 7, etc.

When the operating lever 33 is set to the second position [E], the switching valve 35 is connected to the single acting cylinder 15 and the hydraulic motor 9 side.
As a result, the pump 24 is separated from the tank 25 side, but since the pressure in the first flow path 37 is maintained high, the pilot valve 36 does not return and the above state is maintained. However, in this state, it is not possible to open the crushing arms 4, 4, so the operating arm 33 is greatly operated to instantly move the switching valve 35 to the third position [B], and then immediately return it to the second position. Then, the first flow path 37 once passes through the tank 25 and the pressure in the pilot flow path 40 decreases, so the pilot valve 36 returns to the return position and the single-acting cylinder 15,
Both hydraulic motors 9 are connected to a tank 25. As a result, the crushing arms 4, 4 open, and the angles of their opening and closing surfaces remain unchanged.

Note that FIG. 6 does not show the response delay on the pump 24 side (automatic output control of the pump 24 in response to load fluctuations) when the switching valve 35 is set to the third position [B]. 35 is in the third position [B], even if the single acting cylinder 15 side is connected to the tank 25 and the pressure decreases, at the same time the second flow path 38 on the hydraulic pump 9 side is connected to the pump 24 and the pressure is reduced. increases, so the switching valve 35
Even if the switch valve 35 is set to this position [B], it seems that the pilot valve 36 still remains in the moving position due to the pressure in the pilot flow path 39, but in reality, when the switching valve 35 is set to the third position, the first flow path 37 Due to the high pressure caused by the return spring 18 of the single-acting cylinder 15 and the above-mentioned response delay of the pump 24, it takes a short time before the pressure in the second passage 38 increases sufficiently. However, the pressure in the first flow path 37 decreases to the response pressure of the pilot valve 36, and the pilot valve 36 moves to the return position.

In this state, one crushing operation by the crushing arms 4, 4 has been completed. Therefore, when crushing is to be continued without changing the opening/closing angle of the crushing arms 4, 4, the crushing mechanism 1 is simply moved by the boom. move the position of
Simply repeat the operation of returning the switching valve 35 to the first position [A] using the operating lever 33.

On the other hand, at the next crushing point, the crushing arms 4, 4
When it is desired to change the opening/closing angle of the switching valve 35, the switching valve 35 is set to the third position [B], and the angle of the opening/closing surface is changed with the crushing arms 4, 4 open.

As mentioned above, also in the third embodiment,
The single-acting cylinder 15 and the hydraulic motor 9 are each driven by substantially one switching valve 35 including one operating lever 33 and a pilot valve 36, and the two actuators can be controlled to be inactive at the same time. Furthermore, the number of expensive high-pressure pipes can be reduced to two (pipe lines 27 and 28).

Furthermore, 4 ports 3 in the third embodiment
The closed center type switching valve 35 is normally used for attitude control of a working machine (bucket) attached to the tip of a boom in a power shovel or the like. Therefore, the third embodiment can be easily implemented by simply adding a pilot valve 36 to the conventional switching valve 35 provided in the construction machine.

Although the embodiments have been described above, these hydraulic motors 9 can be used with other hydraulically operated actuators, such as a breaker, which makes crushing more convenient by applying a blow to the part compressed by the crushing arms 4, 4. It may also be an actuator. Furthermore, in the above embodiment, a spring return type single acting cylinder using a spring as the return means was used as the automatic return type single acting cylinder, but compressed gas was used instead of the spring to achieve the same effect as a spring. It can also be made into eggplant. Further, in the embodiment, hydraulic pressure is used as the drive source, but mechanically, general fluid pressure such as pneumatic pressure or water pressure can be used.

[0043]

[Effects of the Invention] The operability of the crushing device is improved and the work efficiency is improved. The number of long high-pressure pipes and the number of required switching valves are halved, reducing piping costs. While opening the crushing arm with one operating lever, you can drive another actuator (hydraulic motor) that shares a switching valve.

[Brief explanation of drawings]

FIG. 1 shows a first embodiment of a hydraulic circuit according to the present invention.

FIG. 2 is a partially cutaway front view of the bracket and crushing mechanism (opened state).

FIG. 3 is a sectional view showing the location of the rotating plate.

FIG. 4 is a partially cutaway front view of the crushing mechanism (closed state).

FIG. 5 shows a second embodiment of the hydraulic circuit according to the present invention.

FIG. 6 shows a third embodiment of a hydraulic circuit according to the present invention.

FIG. 7 is a mechanical diagram schematically showing a conventional example.

[Explanation of symbols]

1 Crushing mechanism 4 Crushing arm 7 Rotating plate 9 Hydraulic motor 11 Closed center type switching valve 14 with 4 ports and 3 positions High pressure piping 15 Spring return type single acting cylinder 26 Open center type switching valve with 4 ports and 3 positions 33 Operation lever

Claims (4)

[Claims] Claim 1: A crushing mechanism in which a pair of crushing arms are connected by an automatic return type single-acting cylinder having a return means, and which can be opened and closed so that the pair of crushing arms are closed when the cylinder is driven by pressurized fluid. and a hydraulic motor operated by the same pressurized fluid, and a 4-port, 3-position open center type switching valve is interposed between these and the pump and tank, and the first load port of the switching valve is set to the above-mentioned automatic return mode. A second load port is connected to the flow path to the hydraulic motor, and the fluid outlet side of the hydraulic motor is connected back to the fluid inlet side of the motor via the relief valve. A crushing device characterized in that it is also connected to a flow path to an automatic return type single-acting cylinder via a check valve. 2. A crushing mechanism in which a pair of crushing arms are connected by an automatic return type single-acting cylinder having a return means, and which can be opened and closed so that the pair of crushing arms are closed when the cylinder is driven by pressurized fluid. , and another actuator that operates with the same pressurized fluid, and a 4-port, 3-position open center type switching valve is interposed between these and the pump and drain, and the first load port of the switching valve is set to the above-mentioned automatic return mode. A crushing device characterized in that a second load port is connected to a flow path to another actuator in a flow path to a mold single-acting cylinder. 3. A crushing mechanism in which a pair of crushing arms that can be opened and closed are connected in a direction in which an automatic return type single-acting cylinder having return means is connected in a direction in which the arms are closed when the cylinders are driven by pressurized fluid. and another actuator operated by pressurized fluid, and between these and the pump and drain, there is a 4 port 3 position closed center type switching valve and the first to third load sides 3 driven by this.
A first position in which all three ports on the load side are directly connected to the drain, a first position in which the first load port is connected to the pump port of the pilot valve, a second load port to the same tank port, and a third load side A 5-port, 2-position automatic return type pilot valve having a second position for closing the port, a return position at the first position, and a movement position by pilot pressure at the second position is interposed between the switching valve and the pilot valve. However, one of the two load side ports of the switching valve is connected to the pump port of the pilot valve through a first flow path, the other is connected to the tank port through a second flow path, and the first and second flow paths are connected to each other. A pilot flow path for transmitting the pressure of these flow paths is connected to the valve operation port of the pilot valve, and a first load port of the pilot valve is connected to the automatic return type single valve. A crushing device characterized in that a second load port is connected to a flow path to another actuator in a flow path to a dynamic cylinder. 4. The crushing apparatus according to claim 1, wherein said automatic return type single acting cylinder is a spring return type single acting cylinder, with its return means comprising a spring.