JP2013245456A - Work attachment control device for construction machine, and construction machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a work attachment control device for a construction machine that prevents interference between a guard and a tip attachment when a work attachment is moved mainly from an in-vehicle-width attitude, and the construction machine.SOLUTION: There is provided a work attachment control device 101 for a hydraulic shovel that includes a shovel body, and a work attachment having a boom, an arm, an offset mechanism, and a bucket. In the work attachment control device 101, a boom angle sensor 111, an arm angle sensor 113, and an offset angle sensor 115 detect values associated with the attitude of the work attachment. When detecting the work attachment being in an attitude within a predetermined stop range on the basis of the values associated with the attitude, a controller 109 stops a discharging-side operation of the bucket by a bucket discharging stop electromagnetic proportional valve 129.

Description

  The present invention relates to a construction machine work attachment control device and a construction machine.

  An offset hydraulic excavator will be described with reference to FIGS. The hydraulic excavator is configured such that an upper swing body 2B is mounted on a crawler-type lower traveling body 2A, and a work attachment 3 is mounted on the upper swing body 2B.

  The work attachment 3 includes a boom 5 that can be raised and lowered around a boom foot pin 4, an arm 7 that is pivotally attached to the tip of the boom 5 around the boom top pin 6, and an arm top pin 8 that is attached to the tip of the arm 7. The bucket 9 is pivotally mounted around it, and various operations such as excavation and loading are performed by the undulation and bending operation of the work attachment 3.

  The boom 5 includes a rear boom 5a and a front boom (also referred to as an offset boom) 5b. The arm 7 and the bucket 9 move (offset) in parallel to the left and right by the left and right pivoting movement of the front boom 5b with respect to the rear boom 5a. Work is performed. FIG. 9 shows a state offset to the left side, and α is the offset angle.

  Also, the work attachment 3 includes a boom cylinder 10 that rotates the boom 5, an arm cylinder 11 that rotates the arm 7, a bucket cylinder 12 that rotates the bucket 9, and an offset cylinder 13 that rotates the front boom 5b left and right ( FIG. 9) is provided.

  The upper swing body 2B is provided with a cab 14 on one side of the front left and right sides (usually the left side of the front as shown in the figure, which will be described below in this example), and various operations are performed in the cab 14. . On the right side of the cab 14, a guard 16 that constitutes the design surface of the upper swing body 2 </ b> B is provided.

  In such a hydraulic excavator, as a means for preventing interference between the bucket 9 and the cab 14, an interference region (interference between the bucket 9 and the cab 14 may occur when the arm top pin 8 enters the front of the cab 14. It is known that when the arm top pin 8 enters this interference area, the operation of the work attachment (usually boom raising, arm pulling, and left offset operations) is automatically stopped (for example, (See Patent Document 1).

Japanese Patent Laid-Open No. 3-156037

  In the construction machine (for example, a hydraulic excavator) as described above, depending on the dimensions of the guard and the work attachment, the tip attachment (for example, bucket) may interfere not only with the cab but also with the guard. In particular, when an excavation operation is performed after the turning posture within the vehicle width (the posture shown in FIG. 1), the tip attachment may interfere with the guard by the operation of the operator.

  Therefore, an object of the present invention is to provide a construction machine work attachment control device and a construction machine that prevent interference between a guard and a tip attachment when the work attachment is moved mainly from a turning posture within a vehicle width.

  To achieve the above object, the present invention provides a work attachment control device for a construction machine comprising a construction machine main body, a work attachment having a boom, an arm, an offset mechanism, and a tip attachment, A detection means for detecting a value related to a posture; and a discharge side of the tip attachment when the detection means detects that the posture of the work attachment is within a predetermined stop range based on the value related to the posture A work attachment control device for a construction machine is provided that includes a stopping means for stopping (prohibiting) the operation.

  Here, it is preferable to further include a release means for releasing the stop of the discharge side operation by the stop means.

  In addition, when the detection means detects that the posture of the work attachment is in a deceleration range different from the stop range, the detection unit further includes a deceleration unit that decelerates the discharge-side operation of the tip attachment. It is preferable to reduce the degree of deceleration of the discharge side operation as the posture of the work attachment moves away from the stop range.

  Further, the construction machine main body includes an upper swing body to which the work attachment is attached and a lower traveling body on which the upper swing body is mounted, and the stop means rotates the upper swing body with respect to the lower traveling body. It is preferable that the discharge side operation of the tip attachment is stopped when the distance between the center and the predetermined portion of the arm is less than a predetermined value.

  Further, the present invention provides a construction machine main body, a work attachment having a boom, an arm, an offset mechanism, and a tip attachment, a detection means for detecting a value related to the posture of the work attachment, and the detection means to the posture. A construction machine comprising: a control device having stop means for stopping the discharge side operation of the tip attachment when it is detected that the posture of the work attachment is within a predetermined stop range based on a related value; Yes.

  According to the construction machine work attachment control device according to claim 1 and the construction machine according to claim 5, the operator mistakenly performs the discharge side operation of the tip attachment in a situation where the posture of the work attachment is within a predetermined stop range. The tip attachment is prevented from interfering with the construction machine body.

  According to the construction machine work attachment control device of the second aspect, when the discharge side operation is stopped by the stopping means, the work can be continued by releasing the operation.

  According to the construction machine work attachment control device of the third aspect, the discharge side operation is not performed suddenly at the position where the stop of the discharge side operation is released, and the discharge side operation can be performed smoothly.

  According to the work attachment control device for a construction machine according to the fourth aspect, the discharge side operation can be accurately stopped by stopping the discharge side operation with reference to a predetermined portion of the arm.

The right view which shows the hydraulic shovel (turning posture in a vehicle width) by embodiment of this invention. The right side view which shows the state which operated the bucket to the discharge | release side from the turning posture in a vehicle width in the hydraulic shovel of FIG. The top view which shows the hydraulic shovel of FIG. The block diagram which shows the work attachment control apparatus of the construction machine by embodiment of this invention. The circuit diagram of the part relevant to control of the bucket in the hydraulic excavator by embodiment of this invention. The flowchart which shows the procedure of the bucket deceleration / stop control by embodiment of this invention. The graph which shows the relationship between the arm tip position and the bucket discharge | release pilot pressure in the hydraulic shovel by embodiment of this invention. The left view which shows a well-known offset type hydraulic excavator. The top view which shows a well-known offset type hydraulic excavator.

  A construction machine work attachment control apparatus according to an embodiment of the present invention will be described with reference to FIGS. Since the structure of the hydraulic excavator itself is the same as the conventional one, the same parts as those in FIGS. 8 and 9 are denoted by the same reference numerals, and redundant description is omitted.

  FIG.1 and FIG.2 is the figure which looked at the hydraulic excavator 1 by this embodiment from the right side (the side opposite to the side with the cab 14). FIG. 1 shows a so-called turning posture in the vehicle width, and the bucket 9 is folded to the excavation side. FIG. 3 is a view of the hydraulic excavator 1 in the vehicle width turning posture of FIG. 1 as viewed from above. The arm 7 and the bucket 9 are offset to the right by the offset mechanism. In this state, the bucket 9 and the guard 16 are in a position overlapping in the vertical direction.

  In such a hydraulic excavator 1, when the work attachment 3 is moved from a posture for excavation work or the like to a turning posture in the vehicle width (FIG. 1), the operator normally performs the operation with care, and therefore the bucket 9 is attached to the guard 16. There is little risk of interference. On the other hand, when the work attachment 3 is moved forward from the turning posture within the vehicle width, there is a high possibility that the operator is aware that the operator is moving to the safe side and attention is not paid. At this time, the guard 9 and the toe of the bucket 9 may interfere with each other by inadvertently moving the bucket 9 to the discharge side (state shown in FIG. 2).

  FIG. 4 shows the work attachment control device 101 of the hydraulic excavator 1. The control device 101 includes a controller 109, a boom angle sensor 111, an arm angle sensor 113, an offset angle sensor 115, an automatic stop release switch 117, a boom raising stop electromagnetic proportional valve 121, an arm pulling stop electromagnetic proportional valve 123, and an offset left stop electromagnetic proportional. A valve 125, an offset right stop electromagnetic proportional valve 127, and a bucket discharge stop electromagnetic proportional valve 129 are provided.

  The controller 109 is provided in the cab 14. The controller 109 receives signals from the angle sensors 111 to 115 and the automatic stop release switch 117, performs various arithmetic processes, and outputs signals to the electromagnetic proportional valves 121 to 129. The memory in the controller 109 stores the dimensions of the rear boom 5a, the front boom 5b, and the arm 7.

  The boom angle sensor 111 is provided on the boom foot pin 4 (see FIG. 8) of the excavator 1. The boom angle sensor 111 detects the angle of the boom 5 every time the boom 5 moves as the boom cylinder 10 expands and contracts, and inputs a voltage value corresponding to the angle to the controller 109.

  The arm angle sensor 113 is provided on the boom top pin 6. The arm angle sensor 113 detects the angle of the arm 7 every time the arm 7 moves as the arm cylinder 11 expands and contracts, and inputs a voltage value corresponding to the angle to the controller 109.

  The offset angle sensor 115 is provided on the offset pin 18 (see FIG. 9). The offset angle sensor 115 detects the offset angle each time the offset angle changes as the offset cylinder 13 expands and contracts, and inputs a voltage value corresponding to the angle to the controller 109.

  The automatic stop release switch 117 is provided in the cab 14 and is used by an operator to release the automatic stop state by operating this switch when the discharge operation of the bucket 9 is automatically stopped as will be described later. It is.

  The operating direction and speed of the boom cylinder 10, arm cylinder 11, bucket cylinder 12, and offset cylinder 13 are controlled by operating levers provided in the cab 14. The boom raising stop electromagnetic proportional valve 121, the arm pulling stop electromagnetic proportional valve 123, the offset left stop electromagnetic proportional valve 125, the offset right stop electromagnetic proportional valve 127, and the bucket release stop electromagnetic proportional valve 129 are hydraulic pressures directly connected to the operation lever. It is provided between the remote control valve and the control valve of the corresponding cylinder.

  The boom raising / stopping electromagnetic proportional valve 121 is of a type in which the supplied current value is proportional to the secondary pressure thereof, and the boom is controlled by moving the spool of the control valve for the boom cylinder 10 from the neutral position with the secondary pressure. Control the movement of 5. Therefore, the boom raising operation can be stopped or decelerated by controlling the current value supplied to the boom raising electromagnetic proportional valve 121 based on the command signal from the controller 109.

  The arm pulling stop electromagnetic proportional valve 123, the offset left stop electromagnetic proportional valve 125, and the offset right stop electromagnetic proportional valve 127 are of the same type as the boom raising stop electromagnetic proportional valve 121. The arm pulling stop electromagnetic proportional valve 123 stops or decelerates the arm pulling operation based on a command signal from the controller 109. The offset left stop electromagnetic proportional valve 125 and the offset right stop electromagnetic proportional valve 127 stop or decelerate the left offset operation and the right offset operation, respectively, based on a command signal from the controller 109.

  FIG. 5 is a circuit diagram of a portion related to the control of the bucket 9 in the excavator 1. The bucket discharge stop electromagnetic proportional valve 129 is provided between the control valve 22 and a hydraulic remote control valve (not shown) directly connected to the operation lever 20. As will be described in detail later, the controller 109 receives a signal related to the posture of the work attachment 3 from each of the sensors, performs a predetermined calculation, and outputs a signal according to the calculation result to the bucket discharge stop electromagnetic proportional valve 129. To do. Thereby, the bucket discharge pilot pressure is controlled (see FIG. 7), and the control for decelerating or stopping the discharge side operation of the bucket 9 (bucket cylinder 12) is performed via the control valve 22.

<Deceleration / stop control of boom, arm and offset>
The boom / arm / offset deceleration / stop control will be briefly described. An interference prevention area is set on the front and upper surfaces of the cab 14 and the guard 16, and information related to the boundary of the interference prevention area is stored in the controller 109. The controller 109 calculates the position of the arm tip (the position of the arm top pin 8) based on the signals of the angle sensors and the dimensions of the rear boom 5a, the front boom 5b, and the arm 7 stored in advance. Then, the controller 109 calculates the distance between the position of the arm tip and the interference prevention area, and outputs a signal to each electromagnetic proportional valve that decelerates when approaching the interference prevention area and stops when reaching the interference prevention area. . Since this control is publicly known (Japanese Patent Laid-Open No. 3-1556037), detailed description is omitted.

<Deceleration / stop control of bucket discharge operation>
Next, the procedure of the deceleration / stop control of the bucket discharging operation according to the embodiment of the present invention will be described based on the flowchart of FIG. This control is executed at a predetermined timing in parallel with the boom / arm / offset deceleration / stop control described above.

  First, in S <b> 1, the controller 109 calculates each relative angle from the output values of the boom angle sensor 111, the arm angle sensor 113, and the offset angle sensor 115.

  In S3, the arm tip position (the position of the arm top pin 8) is obtained from the stored dimensions of the rear boom 5a, front boom 5b, and arm 7, and the relative angles obtained in S1, and the turning center is further determined. The radius R (the distance between the arm tip position and the turning center) as the origin is calculated.

  In S5, it is determined whether or not the radius R is less than the predetermined distance R1. The predetermined distance R1 is set, for example, to a distance of working radius + 100 mm at which the tooth tip of the bucket 9 interferes with the guard 16. When the radius R is less than the predetermined distance R1 (stop range) (S5: Yes), a signal for stopping the bucket discharge operation is output to the bucket discharge stop electromagnetic proportional valve 129 (S7). That is, when the arm tip position is inside the circle of radius R1 with the turning center as the origin in plan view, the bucket 9 is prevented from moving even if the operator tries to move the bucket 9 to the discharge side. After the bucket discharge operation is stopped, when the operator operates the automatic stop release switch 117, a signal for releasing the stop of the bucket discharge operation is output from the controller 109 to the bucket discharge stop electromagnetic proportional valve 129, and the operation on the discharge side of the bucket is performed. Will be able to do. In this case, since the operator performs an operation while recognizing the danger that the bucket 9 interferes with the guard 16, there is little possibility of interference.

  On the other hand, when the radius R is equal to or greater than the predetermined distance R1 (deceleration range) (S5: No), the controller 109 outputs a signal to the bucket discharge stop electromagnetic proportional valve 129 according to R (S9). More specifically, as indicated by the solid line in the graph of FIG. 7, when R = R1, a signal that causes the bucket discharge pilot pressure to become zero is output to the bucket discharge stop electromagnetic proportional valve 129, and R and R1 A signal is output to the bucket discharge stop electromagnetic proportional valve 129 so that the bucket discharge pilot pressure increases as the difference (R−R1) increases (that is, as the arm tip position moves away from the discharge operation stop region). Therefore, the degree of deceleration of the discharge operation decreases as the bucket 9 moves away from the stop region of the discharge operation. In the present embodiment, control is performed so that the bucket discharge pilot pressure increases with a first-order delay, as indicated by the solid line in FIG.

  By using the electromagnetic proportional valve in this manner, the bucket discharge speed is controlled to gradually increase as the difference between R and R1 (R-R1) increases. Therefore, for example, when excavation work is to be performed, the bucket 9 is moved away from the turning center in a state in which the operation lever 20 of the bucket is largely operated to the discharge side, and when R = R1 is exceeded, the bucket 9 suddenly Can be prevented from moving.

  The excavator work attachment control device according to the present invention is not limited to the above-described embodiment, and various modifications and improvements can be made within the scope described in the claims.

  In the above-described embodiment, the bucket discharging operation is stopped when the radius R of the arm tip position with the turning center as the origin is less than the predetermined distance R1, but the invention is not limited to such an embodiment. For example, the bucket discharging operation may be stopped when it is determined that the angle of the boom 5 and the angle of the arm 7 are within a predetermined range based on signals from the boom angle sensor 111 and the arm angle sensor 113. At this time, in addition to the angles of the boom 5 and the arm 7, an offset angle may be considered. According to such a modification, the bucket discharge operation is stopped based on the angle without calculating the arm tip position, so that it is possible to reduce the processing load.

  In the above-described embodiment, the electromagnetic proportional valve (bucket discharge stop electromagnetic proportional valve 129) is used to decelerate and stop the bucket discharge operation. However, it is also possible to use an electromagnetic valve that performs ON / OFF control. In this case, the relationship between the arm tip position and the bucket discharge pilot pressure is as shown by the dotted line in FIG. 7, where the bucket discharge pilot pressure is zero when R <R1, and the bucket discharge pilot pressure is constant when R ≧ R1. .

  In the above-described embodiment, control is performed so that the bucket discharge pilot pressure increases with a first-order delay in the deceleration range of the bucket discharge operation. However, the embodiment is not limited to such an embodiment, and for example, increases linearly. Control may be performed.

  In the embodiment described above, angle sensors (boom angle sensor 111, arm angle sensor 113, offset angle sensor 115) are used as detection means for detecting a value related to the posture of the work attachment. Not limited. For example, a stroke sensor that detects the expansion / contraction length of each cylinder or an inclination sensor that detects an angle (inclination) between the vertical direction and the reference direction may be used.

  In the embodiment described above, the control device for the hydraulic excavator provided with the bucket as the tip attachment has been described, but the tip attachment is not limited to the bucket. You may apply this invention to the control apparatus of the construction machine provided with the crusher, the breaker, etc. as a tip attachment.

  As described above, the construction machine work attachment control device according to the present invention is useful as a work attachment control device such as a hydraulic excavator used for construction work or the like.

1 hydraulic excavator, 2A lower traveling body, 2B upper turning body,
3 work attachments, 4 boom foot pins, 5 booms,
5a Rear boom, 5b Front boom, 6 Boom top pin,
7 arm, 8 arm top pin, 9 bucket,
10 Boom cylinder, 11 Arm cylinder, 12 Bucket cylinder,
13 Offset cylinder, 14 cab, 16 guard,
18 Offset pin, 20 Operation lever, 22 Control valve 101 Work attachment control device, 109 Controller,
111 Boom angle sensor, 113 Arm angle sensor,
115 Offset angle sensor, 117 Automatic stop release switch,
121 Boom raising stop solenoid proportional valve, 123 Arm pulling stop solenoid proportional valve,
125 Offset left proportional solenoid valve, 127 Offset right proportional solenoid valve,
129 Bucket release stop solenoid proportional valve

Claims (5)

A construction machine work attachment control device comprising a construction machine main body, a work attachment having a boom, an arm, an offset mechanism, and a tip attachment,
Detecting means for detecting a value related to the posture of the work attachment;
Stop means for stopping the discharge side operation of the tip attachment when the detection means detects that the posture of the work attachment is within a predetermined stop range based on a value related to the posture. A construction machine work attachment control device.   The work attachment control device for a construction machine according to claim 1, further comprising release means for releasing the stop of the discharge side operation by the stop means. When the detection unit detects that the posture of the work attachment is in a deceleration range different from the stop range, the detection unit further includes a deceleration unit that decelerates the discharge side operation of the tip attachment,
3. The work attachment control device for a construction machine according to claim 1, wherein the deceleration unit reduces the degree of deceleration of the discharge side operation as the posture of the work attachment moves away from the stop range. The construction machine main body includes an upper swing body to which the work attachment is attached, and a lower traveling body on which the upper swing body is mounted,
The said stop means stops the discharge | release side operation | movement of the said tip attachment when the distance of the turning center of the said upper turning body with respect to the said lower traveling body and the predetermined part of the said arm is less than predetermined value. Item 4. The work attachment control device for a construction machine according to any one of Items 1 to 3. The construction machine body,
A work attachment having a boom, an arm, an offset mechanism, and a tip attachment;
Detecting means for detecting a value related to the posture of the work attachment; and when the detection means detects that the posture of the work attachment is within a predetermined stop range based on the value related to the posture. And a control device having stop means for stopping the attachment-side operation of the attachment.

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