JP2020117997A - Construction machine - Google Patents

Abstract

To provide a technique that can reliably crush an object to be crushed while reducing operation loads on operators for a construction machine in which the attachment tip has a crusher.SOLUTION: A demolition machine comprises a crusher hydraulic cylinder 50, a main valve 51, a controller 6, and a close button 7. The main valve 51 is configured to be able to switch between an opening operation state for operating a crusher in an opening manner and a closing operation state for operating the crusher on a closing manner. When determining that closing operation finishes, the controller 6 outputs an opening excitation signal for a predetermined period from when closing operation finishes to when the predetermined period passes.SELECTED DRAWING: Figure 2

Description

The present invention relates to a construction machine equipped with a crusher at a tip of an attachment.

Conventionally, there has been proposed a drive device for an attachment type crushing device that can automatically repeat opening and closing operations without an operator performing a manual operation (see, for example, Patent Document 1). Specifically, in the technique of Patent Document 1, the hydraulic pressures on the extension side and the retraction side of the hydraulic cylinder are detected, and when the hydraulic pressure exceeds a required value, the extension/retraction operation of the rod is controlled to be reversed. .. According to this, since the operator does not have to operate the operation lever many times, the operation load is reduced.

JP-A-9-262488

However, in Patent Document 1, the rod repeats reciprocating motion according to the value of the hydraulic pressure, and the movable member repeatedly opens and closes accordingly, so that the operator intends to continue the closing operation. However, there is a problem that the movable member cannot be crushed with certainty because the movable member is opened without permission against the intention.

Therefore, it is an object of the present invention to provide a technique capable of reliably crushing an object to be crushed in a construction machine equipped with a crusher at the tip of an attachment while reducing the operation load on the operator.

In order to achieve the above object, the present invention provides a crusher attached to the tip of a work attachment, a crusher hydraulic cylinder for opening and closing the crusher, and a pressure oil supplied to the crusher cylinder. A main valve configured to switch between an open operating state in which the crusher is opened and a closed operating state in which the crusher is closed, and an open excitation for switching the main valve to the open operating state. A controller that controls the output of the signal and an output unit that outputs a closing operation signal indicating whether or not the operator has performed a closing operation to the controller are provided, and the controller has completed the closing operation based on the closing operation signal. If it is determined that the construction machine is characterized in that the open excitation signal is output for a predetermined period from the time when the closing operation is completed until a certain time elapses.

Here, when the controller determines that the closing operation is accepted based on the closing operation signal during the predetermined period, it is preferable that the controller stop outputting the opening excitation signal.

Further, the crusher further comprises detection means for detecting the most opened state as an open end, and the controller stops outputting the open excitation signal when the open end is detected in the predetermined period. Is preferred.

Further, an opening operation receiving means for receiving an opening operation for instructing an opening operation of the crusher by the operator, an automatic opening mode for automatically opening the crusher via the controller, and an opening operation receiving means. It is preferable to further include a mode switching means for switching between a manual opening mode in which the crusher is manually opened by way of the mode.

According to the present invention, when it is determined that the closing operation is completed, the open excitation signal is output for a predetermined period from the time when the closing operation is completed to the elapse of a certain time. Therefore, the closing operation of the crusher is reliably continued while the operator is performing the closing operation, and the opening operation of the crusher is automatically started after the closing operation is completed. Therefore, in a construction machine including a crusher at the tip of the attachment, it is possible to reliably crush the object to be crushed while reducing the operation load on the operator.

The side view which shows the disassembly machine provided with a crusher. The hydraulic circuit diagram about the hydraulic cylinder for crushers for opening and closing a crusher (1st Embodiment). The graph which shows the relation between the closing operation of an operator and the operating condition of a crusher. The hydraulic circuit diagram which concerns on 2nd Embodiment. The hydraulic circuit diagram which concerns on a 1st modification. The hydraulic circuit diagram which concerns on a 2nd modification. The hydraulic circuit diagram which concerns on a 3rd modification.

<1. First Embodiment>
A construction machine according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 3. Hereinafter, the dismantling machine 1 shown in FIG. 1 will be illustrated as an example of the construction machine according to the present invention.

As shown in FIG. 1, the dismantling machine 1 includes a lower traveling body 2, an upper revolving structure 3 mounted on the lower traveling structure 2, and a work attachment 4 mounted on the upper revolving structure 3. To be done.

A small crusher 5 (hereinafter, also simply referred to as “crusher 5”) for crushing a crushing target such as concrete is attached to the tip of the work attachment 4.

The crusher 5 includes a crusher hydraulic cylinder 50 shown in FIG. The crusher 5 is configured to open and close as the hydraulic cylinder 50 for the crusher expands and contracts, and the opening and closing operation crushes (crushes) the object to be crushed.

In the first embodiment, the structure shown in FIG. 2 is adopted as the hydraulic circuit of the hydraulic cylinder 50 for the crusher. Specifically, the hydraulic circuit of the crusher hydraulic cylinder 50 includes a main valve 51, a closing operation solenoid valve 53, and an opening operation solenoid valve 55.

The main valve 51 is a valve for controlling the pressure oil supplied to the crusher hydraulic cylinder 50. Specifically, the main valve 51 supplies the pressure oil for opening the crusher 5 to the hydraulic cylinder 50 for the crusher, and the main valve 51 for supplying the pressure oil for closing the crusher 5 to the hydraulic cylinder 50 for the crusher. It is configured so that it can be switched to the supply closed operation state.

Specifically, the main valve 51 is switched to the above-described closing operation state according to the pilot pressure supplied from the closing operation solenoid valve 53. When the main valve 51 is switched to the closed operation state, the pressure oil sent from the pump is supplied to the bottom side of the crusher hydraulic cylinder 50, and the pressure oil on the rod side of the crusher hydraulic cylinder 50 is supplied to the tank. Return. As a result, the crusher hydraulic cylinder 50 extends, and as a result, the crusher 5 closes.

Further, the main valve 51 is switched to the open operation state described above according to the pilot pressure supplied from the opening operation solenoid valve 55. When the main valve 51 is switched to the open operation state, the pressure oil sent from the pump is supplied to the rod side of the crusher hydraulic cylinder 50, and the pressure oil on the bottom side of the crusher hydraulic cylinder 50 is supplied to the tank. Return. As a result, the crusher hydraulic cylinder 50 contracts, and as a result, the crusher 5 is opened.

The main valve 51 maintains the neutral state when the pilot pressure is not supplied. The neutral state is a state in which the oil passage that connects the hydraulic cylinder 50 for the crusher to the pump and the tank is blocked (the state shown in FIG. 2).

The closing operation solenoid valve 53 is a valve that operates according to the closing excitation signal output from the controller 6. The closing operation solenoid valve 53 is switched to a state in which pilot pressure is supplied to the main valve 51 in response to the closing excitation signal. Along with this, the main valve 51 is switched to the closed operation state described above, the crusher hydraulic cylinder 50 extends, and the crusher 5 closes.

The opening operation solenoid valve 55 is a valve that operates according to the opening excitation signal output from the controller 6. The opening operation solenoid valve 55 is switched to a state in which pilot pressure is supplied to the main valve 51 in response to the opening excitation signal. Along with this, the main valve 51 is switched to the open operation state described above, the hydraulic cylinder 50 for the crusher contracts, and the crusher 5 opens.

The controller 6 is a control device that controls the output of the above-described closed excitation signal and the output of the above-described open excitation signal.

The controller 6 is connected with a close button 7 for accepting a closing operation of the crusher 5 by an operator (operator) and an open end detection sensor 8 for detecting the open state of the crusher 5 as the open end. Has been done.

The close button 7 outputs an ON signal to the controller 6 when it is pressed by the operator, and outputs an OFF signal to the controller 6 when it is not pressed by the operator. The close button 7 is an example of the output means according to the present invention. Further, the ON signal and the OFF signal are signals (ON signal: present, OFF signal: not present) indicating the presence or absence of the closing operation by the operator, and are examples of the closing operation signal according to the present invention.

The open end detection sensor 8 is configured as a cylinder stroke sensor, detects a state in which the crusher hydraulic cylinder 50 is most contracted (that is, a state in which the crusher 5 is most open) as an open end, and outputs a signal indicating the open end (hereinafter referred to as “open end”). , Also referred to as “open end signal”) to the controller 6.

The controller 6 determines that the operator is performing the closing operation while the ON signal is being output from the closing button 7, and continues to output the closing excitation signal to the closing operation solenoid valve 53.

After that, when the output signal from the close button 7 is switched from the ON signal to the OFF signal, the controller 6 determines that the closing operation by the operator is completed, and stops the output of the closing excitation signal to the closing operation solenoid valve 53. .. At the same time, the controller 6 starts the output of the opening excitation signal to the opening operation solenoid valve 55, and a predetermined period from the time when the closing operation ends to the elapse of a predetermined time (hereinafter, “automatic opening operation period”). (Also referred to as “open”), the open excitation signal is continuously output to the open operation solenoid valve 55. Thereby, the crusher 5 continues the opening operation for the automatic opening operation period. The designer can arbitrarily set the automatic opening operation period.

However, even during the automatic opening operation period, the opening operation of the crusher 5 is forcibly terminated in the following cases.

Specifically, when the output signal from the close button 7 is switched from the OFF signal to the ON signal during the automatic opening operation period (that is, when the closing operation is performed again), the controller 6 controls the opening operation of the opening excitation signal. The output to the solenoid valve 55 is stopped, and the closing excitation signal is output to the closing solenoid valve 53. Along with this, the opening operation of the crusher 5 is forcibly terminated, and the closing operation of the crusher 5 starts.

Also, when the opening end signal is output from the opening end detection sensor 8 during the automatic opening operation period, the controller 6 also stops outputting the opening excitation signal to the opening operation solenoid valve 55. Along with this, the opening operation of the crusher 5 is forcibly terminated.

Hereinafter, the relationship between the closing operation of the operator and the operation status of the crusher 5 will be described in detail with reference to FIG.

First, in the period until the closing operation (pressing the closing button 7) is accepted (the period from time t0 to time t1), the main valve 51 is in the neutral state, the crusher 5 does not open and close, and the initial state is set. To maintain.

After that, when the closing operation is accepted at time t1, the controller 6 outputs a closing excitation signal to the closing operation solenoid valve 53. Along with this, the main valve 51 is switched to the closing operation state, and the crusher 5 starts the closing operation.

The controller 6 continues to output the closing excitation signal to the closing operation solenoid valve 53 for the period until the closing operation ends (the period from time t1 to time t2). Along with this, the crusher 5 continues to close.

When the closing operation ends at time t2, the controller 6 stops outputting the closing excitation signal to the closing operation solenoid valve 53, and starts outputting the opening excitation signal to the opening operation solenoid valve 55. Along with this, the main valve 51 is switched from the closed operation state to the open operation state, and the crusher 5 finishes the close operation and automatically starts the open operation.

The controller 6 continues to output the opening excitation signal to the opening operation solenoid valve 55 for a predetermined period (automatic opening operation period) from the time when the closing operation is completed (time t2) until the preset constant time TM1 elapses. .. Then, when the predetermined time TM1 has elapsed, the controller 6 stops the output of the open excitation signal to the open operation solenoid valve 55. Accordingly, the crusher 5 does not perform the opening/closing operation until the main valve 51 is switched from the open operation state to the neutral state and the next closing operation (time t3) is received.

When the closing operation is accepted again at time t3, the controller 6 outputs a closing excitation signal to the closing operation solenoid valve 53. When the closing operation ends at time t4, the controller 6 stops outputting the closing excitation signal to the closing operation solenoid valve 53, and starts outputting the opening excitation signal to the opening operation solenoid valve 55.

As described above, normally, the controller 6 outputs the open excitation signal for the open operation during the period from the time when the close operation is completed (time t4) until the preset constant time TM1 elapses (automatic open operation period). The output continues to the solenoid valve 55.

However, when the closing operation is accepted again during the period from the time t4 until the constant time TM1 elapses (time t5: a time TM2 shorter than the constant time TM1 elapses from the time t4), the controller 6 causes the open excitation. The output of the signal to the solenoid valve 55 for opening operation is stopped, and the excitation signal for closing is output to the solenoid valve 53 for closing operation. With this control, when the operator performs the closing operation, the opening operation of the crusher 5 is forcibly terminated, and the closing operation of the crusher 5 starts immediately. That is, the closing operation by the operator has priority over the automatic opening operation of the crusher 5. Then, the controller 6 continues to output the closing excitation signal to the closing operation solenoid valve 53 until the closing operation ends (time t6).

As described above, when the open end signal is output from the open end detection sensor 8 even before the elapse of the fixed time TM1, the controller 6 sends the open excitation signal to the open operation solenoid valve 55. Stop output.

According to the above-described first embodiment, when it is determined that the closing operation by the operator has ended, a fixed time (FIG. 3: fixed time TM1) has elapsed from the time when the closing operation ended (FIG. 3: time t2). The crushing machine 5 is automatically opened for a period of time until. Therefore, the closing operation of the crusher 5 is reliably continued while the operator is performing the closing operation, and the opening operation of the crusher 5 is automatically started after the closing operation is completed. Therefore, in the dismantling machine 1 including the crusher 5 at the tip of the attachment, it is possible to reliably crush the object to be crushed while reducing the operation load on the operator.

Further, according to the above-described first embodiment, when the closing operation is received again during the period from the time when the closing operation ends (FIG. 3: time t4) to the elapse of a certain time (FIG. 3: time t5). ), the output of the open excitation signal to the open operation solenoid valve 55 is stopped, and the close excitation signal is output to the close operation solenoid valve 53. Along with this, it is possible to forcibly terminate the opening operation of the crusher 5 and start the closing operation of the crusher 5 without waiting for the elapse of a predetermined time (FIG. 3: constant time TM1). Therefore, if the closing operation is performed, the closing operation can be immediately performed without waiting for the end of the automatically opening operation, so that the work efficiency is improved and it is effective when the crushing object is small.

Further, according to the above-described first embodiment, when the open end signal is output from the open end detection sensor 8 during the period from the time when the closing operation is completed to the elapse of a certain time, the opening excitation signal is opened. The output to the operation solenoid valve 55 is stopped, and the opening operation of the crusher 5 is stopped. Therefore, when the crusher 5 is in the most opened state (relief state), the main valve 51 returns to the neutral state. Therefore, the pressure oil flowing out from the relief valve is reduced, and it is possible to suppress wasteful fuel consumption.

<2. Second Embodiment>
Next, the construction machine according to the second embodiment will be described with reference to FIG. In the following, the description will be centered on the parts that are different from the first embodiment, and the description of the common parts will be omitted.

In the second embodiment, the configuration shown in FIG. 4 is adopted as the hydraulic circuit of the crusher hydraulic cylinder 50. Specifically, the hydraulic circuit of the crusher hydraulic cylinder 50 includes a main valve 51, a pedal front depression valve 52, a pedal rear depression pedal valve 54, an opening operation solenoid valve 55, and a mode switching valve 56. Is configured.

The main valve 51 and the opening operation solenoid valve 55 are the same as those in the first embodiment.

The pedal front depression valve 52 is a valve that supplies pilot pressure to the main valve 51 for switching to a closed operation state when the operator performs the pedal front depression (closing operation).

The pedal back-depressing valve 54 is a valve that supplies pilot pressure to the main valve 51 for switching to an open operation state when the pedal rear-depressing (opening operation) is performed by an operator.

The mode switching valve 56 has an automatic opening mode in which the crushing machine 5 is automatically opened through the opening operation solenoid valve 55 and a manual opening in which the crushing machine 5 is manually opened through the pedal trailing valve 54. This is a valve for switching between modes. The mode switching valve 56 is configured to be switched by a switching signal (ON/OFF signal) output in accordance with a switching operation of a switching switch (not shown) or the like.

When the object to be crushed is crushed using the crusher 5, the mode switching valve 56 is switched to the above-mentioned automatic opening mode. On the other hand, in the case of using an attachment other than the crusher 5 (one that avoids automatic opening), the mode switching valve 56 is switched to the manual opening mode described above.

The pedal back-depressing valve 54 is an example of the opening operation receiving means according to the present invention. The mode switching valve 56 is an example of mode switching means according to the present invention.

In addition to the opening end detection sensor 8 described in the first embodiment, a closing operation detection sensor 9 is connected to the controller 6.

The closing operation detection sensor 9 outputs an ON signal to the controller 6 when the pedal is stepped forward by the operator, and outputs an OFF signal to the controller 6 when the foot is away from the pedal. The closing operation detection sensor 9 is an example of the output unit according to the present invention.

While the ON signal is being output from the closing operation detection sensor 9, the controller 6 determines that the operator is performing the closing operation, and continues to output the closing excitation signal to the closing operation solenoid valve 53.

After that, when the output signal from the closing operation detection sensor 9 is switched from the ON signal to the OFF signal (when the operator releases his/her foot from the pedal), the controller 6 judges that the operator has completed the closing operation, and outputs the closing excitation signal of the closing excitation signal. The output to the closing operation solenoid valve 53 is stopped. At the same time, the controller 6 starts the output of the opening excitation signal to the opening operation solenoid valve 55 and continues to open the opening excitation signal for a period (automatic opening operation period) from the time when the closing operation ends to the elapse of a predetermined time. Continues to be output. Thereby, the crusher 5 continues the opening operation for the automatic opening operation period.

Other configurations and effects are the same as those of the first embodiment, and therefore the description thereof is omitted here.

According to the second embodiment described above, the mode switching valve 56 automatically opens the crusher 5 via the opening operation solenoid valve 55, and the crushing via the pedal rear-pedal valve 54. A manual opening mode in which the machine 5 is opened manually can be switched. Therefore, in the case of using an attachment other than the crusher 5 (one that wants to avoid automatic opening), it is possible to select the manual opening mode and prevent the automatic opening from operating.

<3. Modification>
The construction machine according to the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made within the scope of the claims.

For example, in each of the above-described embodiments, the hydraulic circuit is provided with the open end detection sensor 8, and the most open state of the crusher 5 is detected as the open end, and when the open end is detected during the automatic opening operation period, it is automatically detected. Although the case where the opening operation is forcibly terminated is illustrated, the invention is not limited to this.

As shown in FIGS. 5 and 6, the opening/closing detection sensor 8 may not be provided in the hydraulic circuit, and the opening/closing of the crusher 5 may be controlled without considering the opening end. In that case, even after the crusher 5 is in the most opened state, the controller 6 continues to output the open excitation signal for a period from the time when the closing operation is completed to the elapse of a certain time. In that case, the pressure oil flows out from the relief valve, so the fuel consumption increases, but the cost for installing the open end detection sensor 8 is reduced.

Further, in each of the above embodiments, the case where the open end detection sensor 8 is configured as a cylinder stroke sensor is illustrated, but the invention is not limited to this, and may be configured by a cylinder relief, for example.

In the first embodiment, as shown in FIG. 2, the controller 6 indirectly switches the main valve 51 via the closing operation solenoid valve 53 and the opening operation solenoid valve 54. It is not limited to this. For example, as shown in FIG. 7, the closing operation solenoid valve 53 and the opening operation solenoid valve 54 are not provided in the hydraulic circuit, and the closing excitation signal and the opening excitation signal described above are output from the controller 6 to the main valve 51. The controller 6 may be configured to directly switch the main valve 51. In that case, the main valve 51 is configured as an electromagnetic valve.

INDUSTRIAL APPLICABILITY As described above, the construction machine according to the present invention is suitable for a demolition machine for secondarily crushing concrete or the like generated at a construction site.

1 dismantling machine, 2 lower traveling body, 3 upper revolving body, 4 work attachment,
5 small crusher (crusher), 6 controller, 7 close button, 8 end detection sensor,
9 operation detection sensor, 50 crusher hydraulic cylinder, 51 main valve,
52 front pedal pedal valve, 53 solenoid valve for closing operation,
54 pedal back pedal valve, 55 open operation solenoid valve,
56 mode switching valve, time t0 to t6, TM1 fixed time

Claims (4)

A crusher attached to the tip of the work attachment,
A crusher hydraulic cylinder for opening and closing the crusher,
A main valve configured to control the pressure oil supplied to the crusher cylinder and to be able to switch between an open operation state in which the crusher is opened and a closed operation state in which the crusher is closed,
A controller that controls the output of an open excitation signal that switches the main valve to the open operation state;
Output means for outputting a closing operation signal indicating the presence or absence of a closing operation by an operator to the controller,
Equipped with
When the controller determines that the closing operation is completed based on the closing operation signal, it outputs the opening excitation signal for a predetermined period from the time when the closing operation is completed until a certain time elapses. A characteristic construction machine. The construction machine according to claim 1, wherein when the controller determines that the closing operation is accepted based on the closing operation signal during the predetermined period, the controller stops outputting the opening excitation signal. .. The crusher further comprises detection means for detecting the most open state as an open end,
The construction machine according to claim 1 or 2, wherein the controller stops the output of the open excitation signal when the open end is detected in the predetermined period. An opening operation receiving means for receiving an opening operation by the operator,
A mode switching means for switching between an automatic opening mode for automatically opening the crusher via the controller and a manual opening mode for manually opening the crusher via the opening operation receiving means,
The construction machine according to any one of claims 1 to 3, further comprising:

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