JP5194712B2 - Work machine - Google Patents

Description

  The present invention relates to a working machine such as a crusher provided with a working device that performs a gripping / separating operation of an object.

  FIG. 4 shows an example of a crusher (also called a dismantling machine) provided with a crushing device as a working device.

  In the figure, reference numeral 1 is a crawler type lower traveling body, and 2 is an upper revolving body mounted on the lower traveling body 1 so as to be capable of swiveling. A base machine 3 is constituted by these, and an upper revolving body of the base machine 3. A work attachment 4 for performing joint (bending and stretching) motion is attached to 2.

  The work attachment 4 includes a boom 5 and an arm 6 pin-connected to the tip of the boom 5, and a crushing device 7 as a work device is attached to the tip of the arm 6. Here, a case where a separate boom in which the first and second boom bodies 5a and 5b are pin-connected is used as the boom 5.

  In the figure, 8 is a first boom cylinder for raising and lowering the boom 5 (the entire attachment), 9 is a second boom cylinder for raising and lowering the second boom body 5b of the boom 5, and 10 is an arm cylinder for raising and lowering the arm 6. Is a crusher cylinder for rotating the crusher 7 up and down.

  The crushing device 7 is configured to perform a gripping / separating operation of a crushing object such as a concrete lump by opening and closing a pair of crushing bodies 7a and 7b with a hydraulic cylinder (not shown) (hereinafter referred to as a gripping cylinder). .

  In this specification, the “grabbing” operation includes not only an operation of grasping an object but also an operation of grasping and crushing as in the crushing apparatus 7 illustrated.

In such a crusher, the cylinder pressure (load), the joint angle (work radius), the turning angle of the upper-part turning body 2, and the machine inclination angle are used to prevent the machine from falling due to work in an unstable work posture. If the stability of the machine is determined from various parameters such as the above, and it is determined that the posture is unstable in advance, a display and a warning action will be given to alert the operator, A technique for automatically stopping the operation (for example, the tilting operation or turning operation of the work attachment 4) is known (see Patent Document 1).
JP-A-5-18122

  However, if the posture becomes unstable as in the known art, the method of automatically stopping all operations to the unstable side regardless of the operator's intention as the risk avoidance control will cause the machine to stop due to stop reaction or shock. It may fall into a more unstable state than before.

  Also, in the process of transitioning from an unstable posture to a stable posture, all movements to the unstable side are restricted, so an unstable side operation is required temporarily to avoid surrounding buildings and other obstacles. There was a problem that it could not handle the case.

  Accordingly, the present invention provides a work machine that can eliminate the adverse effects of risk avoidance control while preventing work from continuing in an unstable posture.

According to the first aspect of the present invention, a work attachment for performing a joint motion is attached to the base machine, and a work device that is driven by an actuator to perform a grasping / separating operation of an object is provided at the tip of the work attachment. The machine includes a work posture detecting means for detecting a work posture of the machine such as a joint angle and a load of the work attachment, a tilt angle of the machine, and a controller. The controller receives a detection signal from the work posture detecting means. Based on this, it is determined whether or not the working posture of the machine is a predetermined unstable posture, and when it is determined as an unstable posture, the actuator is controlled as a joint motion of the work attachment as risk avoidance control. Attachment operation, machine operation such as turning operation of the base machine, and release operation of the work device are allowed. Those that are configured to limit only the gripping operation of the working device while.

A second aspect of the present invention, in the configuration of claim 1, the controller, as a limitation of the gripping operation of the working device is the danger avoidance control, in which is configured to stop the掴 seen operation.

The invention according to claim 3, in the configuration of claim 1, the controller, the controller, as a limitation of the gripping operation of the working device is the danger avoidance control, in which is configured to decelerate the掴 seen operation .

  According to a fourth aspect of the present invention, in the configuration according to any one of the first to third aspects, the gripping operation of the work device is performed in a hydraulic circuit including a hydraulic actuator that drives the work device and a control valve that controls the operation of the hydraulic actuator. And a controller configured to output a control signal to the control valve.

  According to a fifth aspect of the present invention, in the configuration of the fourth aspect, a hydraulic pilot valve is used as a control valve, and a control valve is provided in a pilot line of the control valve.

According to the present invention, when the machine is in an unstable posture, as the danger avoidance control, only the gripping operation of the work device is limited (stopped in claim 2 and decelerated in claim 3). The work in is virtually impossible.

  Therefore, in order to continue the work, it is only possible to return to a stable posture, and the operator can clearly recognize that the posture is unstable due to the fact that the gripping operation cannot be performed, so the work can be continued in an unstable posture. Can be prevented.

  Moreover, since only the gripping operation of the working device is limited, unlike the known technique that stops all the unstable side operations, no reaction or shock due to the limiting operation occurs. For this reason, there is no possibility that the machine will fall into a more unstable state.

  Further, since only the gripping operation is limited and other operations such as the work attachment tilting operation are not limited, an obstacle avoidance operation for shifting to a stable posture is possible.

  Furthermore, since the releasing operation of the working device is not limited, if the object is held, it can be quickly returned to the stable posture by releasing it.

  From the above points, it is possible to eliminate the adverse effects of the risk avoidance control while preventing the work from continuing in an unstable posture.

  In addition, the machine operation other than the gripping operation is not restricted, that is, the restriction function of many actuators is not required, so that the circuit configuration is simplified, the cost can be reduced, and the circuit design is advantageous.

  Specifically, as in the inventions of claims 4 and 5, a control valve is provided only in the hydraulic actuator circuit for driving the working device (in claim 5, the pilot line of the control valve), and this is controlled only by the controller. Good.

  An embodiment of the present invention will be described with reference to FIGS. Here, the crusher is taken as an example of application.

First embodiment (see FIGS. 1 and 2)
In FIG. 1, 12 is a hydraulic cylinder (hereinafter referred to as a gripping cylinder) as a hydraulic actuator for gripping / separating the crushing device 7, 13 is a hydraulic pump as a hydraulic source, and a hydraulic pilot type switching valve between them. A control valve 14 is provided.

  A remote control valve 17 is connected to the pilot lines 15 and 16 on both sides of the control valve 14. By operating the remote control valve 17, the control valve 14 is switched between the neutral position a, the gripping position b, and the release position c. The expansion / contraction operation of the grip cylinder 12 (the grip / release operation of the crushing device 7) is controlled. Reference numeral 18 denotes a pilot pump as a pilot hydraulic pressure source of the remote control valve 17.

  Among the pilot lines 15 and 16 on both sides of the control valve 14, a control valve 20 that is an electromagnetic switching valve controlled by a controller 19 is provided in the grip-side pilot line 15.

  The control valve 20 is switched between an opening position A for opening the grip-side pilot line 15 and a tank position B for communicating with the tank T by ON / OFF of the solenoid output.

  Therefore, when the control valve 20 is in the open position a, the control valve 14 can be operated to the gripping position b, and when the control valve 20 is switched to the tank position B, the control valve 14 is disconnected from the pilot pressure and cannot be operated to the gripping position b. .

  That is, if the control valve 20 is in the open position (a), the gripping operation of the crushing device 7 of FIG.

  The controller 19 includes a plurality of sensors that detect the boom angle, arm angle (joint angle), boom cylinder pressure (load), machine tilt angle, swing angle of the upper swing body 2, and the like of the work attachment 4 in FIG. A detection signal from the work posture detection means 21 is input.

  The controller 19 determines the current machine stability based on this detection signal, determines whether or not the current working posture of the machine is a predetermined unstable posture, and if it is determined to be an unstable posture, the controller 19 On the other hand, predetermined control for avoiding danger is performed and the alarm device 22 is activated.

  The operation of this point will be described with reference to the flowchart of FIG.

  In step S1, the stability is calculated, and in step S2, it is determined whether or not the posture is unstable.

  In the case of NO (determined as a stable posture) here, the process proceeds to step S3, and a normal output signal, that is, a signal (solenoid current) for setting to the open position a is output to the control valve 20.

  On the other hand, in the case of YES (determined as an unstable posture), in step S4, output stop processing, that is, processing for stopping output of a signal for setting the control valve 20 to the open position a is performed.

  In step S5, a signal is output to the alarm device 22 to perform an alarm operation (one or both of display on a monitor screen and generation of an alarm sound) for alerting the operator.

  Thus, in the unstable posture, even if the remote control valve 17 is gripped, the control valve 14 is not switched to the gripping position b, and the gripping operation of the crushing device 7 is stopped.

  Therefore, the only way to continue the work is to return the machine to a stable posture. Further, since the gripping operation cannot be performed, the operator can clearly recognize that the posture is unstable. With these two points, it is possible to prevent work from continuing in an unstable posture.

  Moreover, only the gripping operation of the crushing device 7 is stopped, and other machine operations (attachment operation, turning operation, etc.) are allowed regardless of whether they are stable or unstable. Unlike the known technology that stops all machine operations, there is no reaction or shock caused by the stop. For this reason, there is no possibility that the machine will fall into a more unstable state.

  In addition, since only the gripping operation is limited and other operations such as a tilting operation of the work attachment are allowed, an operation for avoiding an obstacle such as a building is possible in order to shift to a stable posture.

  Furthermore, since the releasing operation of the crushing device 7 is possible, if the object is gripped, it can be quickly returned to the stable posture by releasing it.

  From the above points, it is possible to eliminate the adverse effects of risk avoidance control as in the known technology while preventing work in an unstable posture.

  In addition, machine operations other than the gripping operation are not stopped, that is, many actuator stop functions are unnecessary, and control is performed in the circuit of the gripping cylinder 12 (the gripping side pilot line 15 of the control valve 14) as in this embodiment. Since the valve 20 is provided and only this needs to be controlled by the controller 19, the circuit configuration is simplified, the cost can be reduced, and the circuit design is advantageous.

  When the machine returns to a stable posture by the machine operation toward the stable side, the process proceeds from step S2 to step S3 in FIG. 2 to return to the normal processing state, and the crushing operation of the crushing device 7 becomes possible again.

Second embodiment (see FIG. 3)
Only differences from the first embodiment will be described.

  In the first embodiment, as the risk avoidance control, the control valve 20 that is an electromagnetic switching valve is switched to the tank position B to stop the gripping operation of the crushing device 7, whereas in the second embodiment, the grip side A control valve 23 that is an electromagnetic proportional pressure reducing valve is provided in the pilot line 15, and when the posture becomes unstable, the controller 19 controls the control valve 23 to reduce the pilot pressure, thereby decelerating the gripping operation of the crushing device 7. It is configured as follows.

  In this way, even if the gripping operation itself is possible, it becomes difficult to actually perform the gripping operation by decelerating. Therefore, basically, as in the first embodiment, while continuing the work in an unstable posture, It is possible to obtain the effect of eliminating the harmful effects caused by the risk avoidance control as in the known technique.

  By the way, the control valves 20 and 23 which are electromagnetic switching valves or electromagnetic proportional pressure reducing valves are provided in the grip side pipe line of the grip cylinder 12 in FIG. 1, and the grip operation of the cylinder 12 is directly stopped or decelerated. May be.

  Further, the present invention is not limited to the crusher provided with the crushing device 7 that crushes the target object mentioned in the above embodiment as the working device, but includes a transporting machine including a grapple and a clam cell that grips and transports the target object. The present invention can be widely applied to a work machine including a work device that performs a gripping / separating operation.

It is a figure which shows the structure of the cylinder circuit of the crushing apparatus in the crusher concerning 1st Embodiment of this invention, and its control system. It is a flowchart for demonstrating the effect | action of embodiment. FIG. 3 is a view corresponding to FIG. 1 showing a second embodiment of the present invention. It is a schematic side view of a crusher.

DESCRIPTION OF SYMBOLS 1 Lower traveling body 2 Upper revolving body 3 Base machine 4 Work attachment 7 Crushing device 12 Grasping cylinder as actuator for work device 14 Control valve 15 Pilot line on both sides of control valve 17 Remote control valve 19 Controller 20 Control valve 21 Work posture detection means 22 Alarm 23 Control valve

Claims (5)

A work attachment for performing joint motion is attached to the base machine, and a work device that is driven by an actuator to perform gripping / separating operation of an object is provided at the tip of the work attachment. In a work machine that performs a machine operation such as an attachment operation of a work attachment, the controller includes a work posture detecting means that detects a work posture of the machine such as a joint angle and a load of the work attachment, and a tilt angle of the machine, and a controller. Determines whether the working posture of the machine is a predetermined unstable posture based on a detection signal from the working posture detection means, and when it is determined as an unstable posture, control to, attachment dynamic is the articulation of the working attachment , Work machine operation apart of the base machine of the turning operation and the like of the machine operation and the working device is characterized in that it is configured to limit only the gripping operation of the working device while permitting. The controller, as a limitation of the gripping operation of the working device is the danger avoidance control, the working machine according to claim 1, characterized in that it is configured to stop the above掴 seen operation. The controller, as a limitation of the gripping operation of the working device is the danger avoidance control, the working machine according to claim 1, characterized in that it is configured to decelerate the掴 seen operation.   A control valve that restricts the gripping operation of the work device is provided in a hydraulic circuit that includes a hydraulic actuator that drives the work device and a control valve that controls the operation of the hydraulic actuator, and the controller outputs a control signal to the control valve. The work machine according to claim 1, wherein the work machine is configured to perform.   The working machine according to claim 4, wherein a hydraulic pilot valve is used as the control valve, and the control valve is provided in a pilot line of the control valve.

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