JP2007063799A - Operation circuit unit of construction machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable an occasional operation of a hydraulic actuator while reducing cost and an installation space. <P>SOLUTION: This operation circuit unit of a construction machine comprises: hydraulic pilot-type control valves 35-39 for controlling a flow of pressure oil into the hydraulic actuator; electromagnetic decompression valves 35A and 35B-39A and 39B for generating the operation pilot pressure of the valves; a hydraulic cutoff valve 45 capable of cutting off the initial pressure of the valves; and a controller 44 for controlling the valve 45 and the valves 35A and 35B-39A and 39B. The operation circuit unit is equipped with a traveling-speed changeover switch 33 which is connected to a battery 48 and a traveling-speed switching valve 46 without the medium of the controller 44, and harnesses such as a relay harness 58 and a connecting harness 59 which enable the switch 33 to be connected to each of the valve 46 and the selected electromagnetic decompression valve in the release state of connection etc. between the switch 33 and the valve 46. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a construction machine such as a hydraulic excavator, and more particularly to an operation circuit device for a construction machine provided with an electric lever type operation lever.

  For example, a hydraulic excavator, which is one of construction machines, includes a lower traveling body, an upper revolving body provided on the lower traveling body so as to be capable of swiveling, and a boom, an arm, And an articulated working machine including a bucket (working tool). The lower traveling body, the upper swing body, and the work machine constitute a driven member of a hydraulic drive device provided in the hydraulic excavator. The hydraulic drive apparatus generally includes a prime mover such as an engine, at least one hydraulic pump driven by the prime mover, a boom hydraulic cylinder and an arm that respectively drive a boom, an arm, and a bucket by pressure oil discharged from the hydraulic pump. Hydraulic cylinder for bucket, hydraulic cylinder for bucket, traveling hydraulic motor for running undercarriage with pressure oil discharged from hydraulic pump, and upper revolving body with respect to lower running body with pressure oil discharged from hydraulic pump A plurality of hydraulic actuators including a swing hydraulic motor, a plurality of control valves for controlling the flow of pressure oil discharged from the hydraulic pump to the plurality of hydraulic actuators, and a plurality of operation levers operated by an operator. Have.

  The operation lever is roughly classified into a hydraulic pilot system and an electric lever system. In the hydraulic pilot system, an operation amount is converted into a hydraulic pilot signal by reducing a pilot original pressure from a hydraulic source (for example, a pilot pump) with a pressure reducing valve in accordance with an operation amount of an operation lever. In the electric lever system, the amount of operation of the operation lever is detected by a potentiometer, replaced with an electric signal (= operation signal), and output to the controller. The controller generates a drive signal in accordance with the operation signal and outputs the drive signal to an electromagnetic pressure reducing valve that controls the operation pilot pressure applied to the hydraulic pilot control valve, for example.

  By the way, in the case of the electric lever system, for example, it cannot be said that there is a possibility that a controller failure or the like will occur, and even when such normal operation becomes impossible, it is possible to perform the minimum necessary operation for safety. Thus, it is necessary to secure some temporary operation device. From this point of view, conventionally, for example, an operation box composed of an electric lever type operation lever and a potentiometer, a power source switch arranged near the operation box, and a built-in operation box for operating the operation lever. An operation device having an emergency operation switch that operates in conjunction with the operation device has been proposed (for example, see Patent Document 1). In this prior art, when an emergency operation is selected by the power switch, an electrical signal from the emergency operation switch is output to the electromagnetic pressure reducing valve in accordance with the operation of the operation lever.

JP 2000-344466 A

However, there are the following problems in the above-described prior art.
That is, for example, a hydraulic excavator that uses an electric lever system for operating the boom up / down operation, arm dumping / clouding operation, bucket dumping / clouding operation, left / right turning operation of the upper revolving structure When the above-described conventional technology is applied, for example, eight emergency operation switches and a power supply changeover switch corresponding to all these operation modes must be installed. However, it is unlikely that a failure that actually makes all operation modes inoperable will occur, and even if a failure occurs that makes all operation modes inoperable, it is only necessary to perform the minimum necessary operation. There is a circumstance. From this point of view, it is not only expensive to install emergency operation switches and power supply selector switches corresponding to all operation modes as in the prior art, but also a large installation space must be secured in the cab. I had to.

  An object of the present invention is to provide an operation circuit device for a construction machine capable of performing a temporary operation of a hydraulic actuator while reducing cost and installation space.

  (1) In order to achieve the above object, the present invention provides a lower traveling body, an upper revolving body that is turnable on the lower traveling body, and an articulated type that is provided on the upper revolving body so as to be able to rise and fall. To the working machine, a plurality of hydraulic actuators that drive the working machine, a hydraulic pump, a plurality of hydraulic pilot control valves that control the flow of pressure oil from the hydraulic pump to the hydraulic actuator, and the control valve A plurality of electromagnetic pressure reducing valves for generating an operation pilot pressure, a hydraulic pressure cutoff valve capable of shutting off a source pressure supplied to the plurality of electromagnetic pressure reducing valves, and the hydraulic pressure cutoff valve and the plurality of electromagnetic pressure reducing valves according to operation of an operating means In an operation circuit device for a construction machine having a controller for controlling a valve, one terminal is connected to a power source and the other terminal is connected to an electronic component without the controller. The switch, the other terminal of the switch, and the electronic component are disconnected, and the controller, the hydraulic shut-off valve, and the electromagnetic pressure reducing valve are disconnected, and the switch other terminal and the hydraulic pressure are disconnected. Connecting circuit means capable of connecting the shut-off valve and the electromagnetic pressure reducing valve, respectively.

  For example, when performing excavation work or the like, when the operator first operates the lock operating means to the release position, the operation signal is input to the controller, and based on this, the drive signal generated by the controller is output to the hydraulic cutoff valve. . As a result, the hydraulic cutoff valve is switched to the communication position, and the original pressure from the hydraulic source is supplied to the plurality of electromagnetic pressure reducing valves. Then, for example, when the operator operates the work implement operating means with the intention of raising and lowering the work implement, the operation signal is input to the controller, and the drive signal generated by the controller based on this is output to the electromagnetic pressure reducing valve. . Thus, the electromagnetic pressure reducing valve is driven to control the operation pilot pressure to the control valve, and the flow of pressure oil from the hydraulic pump to the hydraulic actuator is controlled. In this way, normally, after the release operation is performed by the lock operation means, the hydraulic actuator is driven by operating the work implement operation means.

  On the other hand, there is a case where it is desired to perform the minimum necessary operation of the work machine even when a controller failure or the like occurs. In such a case, the present invention uses a switch (in other words, an operation circuit for an electronic component) in which one terminal is connected to a power source and the other terminal is connected to an electronic component without using a controller. Specifically, the connection between the other terminal of the switch and the electronic component, the connection between the controller and the hydraulic shut-off valve, and the connection between the controller and the electromagnetic pressure reducing valve are each disconnected. Then, an electromagnetic pressure reducing valve corresponding to the desired operation of the hydraulic actuator is selected, and the selected electromagnetic pressure reducing valve and hydraulic cutoff valve are connected to the other terminal of the switch by connection circuit means. As a result, the hydraulic cutoff valve and the selected electromagnetic pressure reducing valve are driven by the operation of the connected switch, and a predetermined operating pilot pressure to the corresponding control valve is generated. As a result, the minimum necessary operation of the work machine can be performed.

  As described above, in the present invention, a hydraulic actuator is used by using a switch for operating an electronic component without using a controller and connecting a hydraulic cutoff valve and an electromagnetic pressure reducing valve using a connection circuit means instead of the electronic component. You can perform temporary operations. In addition, since the operation of multiple hydraulic actuators can be handled by switching the electromagnetic pressure reducing valve connected to the switch, there is no need to prepare a switch corresponding to all electric lever type operation devices as in the prior art. Furthermore, since an existing switch is used, it is not necessary to provide a new dedicated switch. Therefore, the temporary operation of the hydraulic actuator can be performed while reducing cost and installation space.

  (2) In the above (1), preferably, the connection circuit means is provided with a connector detachably attached to the switch side connector, the connector detachably attached to the hydraulic shutoff valve side connector, and the electromagnetic pressure reducing device. It has a connection harness provided with a detachable connector on the other side of the valve side connector.

  (3) In the above (1), and preferably, a plurality of the switches are provided, and the connection circuit means connects the one switch side connector and the hydraulic shutoff valve side connector to the other switch side. And the electromagnetic pressure reducing valve side connector are connected.

  (4) In the above (2) or (3), more preferably, the connection circuit means is provided with one connector detachably attached to one connector connected to the plurality of electromagnetic pressure reducing valves on the one side, It has a relay harness provided with a plurality of connectors corresponding to a plurality of electromagnetic pressure reducing valves on the other side.

  ADVANTAGE OF THE INVENTION According to this invention, temporary operation of a hydraulic actuator can be performed, aiming at reduction of cost and installation space.

  Embodiments of the present invention will be described below with reference to the drawings.

A first embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a side view showing the overall structure of a small hydraulic excavator to which the present invention is applied. Hereinafter, when the operator is seated in the driver's seat with the excavator shown in FIG. 1, the front side (left side in FIG. 1), rear side (right side in FIG. 1), left side (paper surface in FIG. 1). The front side) and the right side (back side toward the paper surface in FIG. 1) are simply referred to as front side, rear side, left side, and right side.

  In FIG. 1, this hydraulic excavator includes a lower traveling body 2 provided with left and right endless track footwear (crawlers) 1L and 1R (only 1L is shown in FIG. 1) as traveling means, and the lower traveling body 2 An upper revolving body 3 that is pivotably mounted on the upper part of the upper revolving body, and an articulated type that is mounted on a revolving frame 4 that forms the basic lower structure of the upper revolving body 3 so as to be pivotable in the vertical direction. A work machine (front device) 5, a so-called canopy type cab 6 provided on the swivel frame 4, and an upper cover 7 covering most of the cab 6 other than the cab 6 on the swivel frame 4 are provided.

  The lower traveling body 2 includes a substantially H-shaped track frame 8 and drive wheels 9L and 9R rotatably supported near the rear ends of the left and right sides of the track frame 8 (only 9L is shown in FIG. 1). Left and right traveling hydraulic motors 10L and 10R for driving the drive wheels 9L and 9R (only 10L is shown in FIG. 1), and rotatably supported in the vicinity of the front ends of the left and right sides of the track frame 8, Driven wheels (idlers) 11L and 11R (only 11L shown in FIG. 1) that are rotated by the driving force of the drive wheels 9L and 9R via the crawler belts 1L and 1R, respectively, are provided on the front side of the track frame 8 so as to be movable up and down. And a blade 12 for earth removal that moves up and down by a blade hydraulic cylinder (not shown). Further, a swivel bearing (swivel wheel) 13 is arranged at the center of the lower traveling body 2, and a turning hydraulic motor (not shown) for turning the turning frame 4 relative to the lower traveling body 2 near the center of the swirling wheel 13. ) Is built-in.

  The work implement 5 includes a lower boom 14 that is coupled to the revolving frame 4 so as to be pivotable in the vertical direction, an upper boom 15 that is pivotally coupled to the distal end portion of the lower boom 14 in a horizontal direction, and the upper boom 15. An arm cylinder bracket 16 connected to the distal end portion so as to be pivotable in the left-right direction, an arm 17 coupled to the distal end portion of the arm cylinder bracket 16 so as to be pivotable in the vertical direction, and an upper end portion of the arm 17 And a stay 19 that connects the lower boom 14 and the arm cylinder bracket 16, a boom hydraulic cylinder 20 that drives the lower boom 14, and the upper boom 15 together with the lower boom 14. An offset hydraulic cylinder 21 that is movably connected to drive the upper boom 15 and the arm 1 An arm hydraulic cylinder 22 to drive the, and a bucket hydraulic cylinder 23 for driving the bucket 18.

  In the working machine 5 configured as described above, when the offset hydraulic cylinder 21 is extended, the upper boom 15 is turned by the stay 19 with the arm cylinder bracket 16 always facing the front of the hydraulic excavator. Yes. That is, the upper boom 15 is turned in the left-right direction with the arm cylinder bracket 16, the arm 17, and the bucket 18 facing forward.

  The driver's cab 6 is provided on the left side of the revolving frame 4 and includes a seat (driver's seat) 24 on which an operator is seated. 2 is a bird's-eye view showing the detailed structure inside the cab 6 as seen from the direction of arrow II in FIG.

  In FIG. 2, the left and right traveling hydraulic motors 11L and 11R are respectively driven in front of the seat 24 on which the operator in the cab 6 is seated to move the hydraulic excavator forward or backward. Left and right traveling operation levers 25L and 25R that can be operated with feet are provided.

  An optional operation pedal 26L for driving an optional hydraulic actuator (for example, a breaker hydraulic motor) is provided at the left foot portion of the left travel operation lever 25L. An offset operation pedal 26R for driving the offset hydraulic cylinder 21 and turning the upper boom 15 (in other words, the entire work machine 5) to the left and right is provided at the right foot portion of the right travel operation lever 25R. ing.

  On the left side of the seat 24, the swing hydraulic motor is driven by operating the left or right side, and the upper swing body 3 is rotated left or right and the arm hydraulic cylinder 22 is driven by operating the front or rear side. A cross-operating swivel / arm manual operation lever 27L for dumping or crowding the arm 17 and a lock lever 29 for preventing an erroneous operation for cutting off the original pressure from the pilot pump 28 (see FIG. 3 described later). The left console box 30L is provided.

  On the right side of the seat 24, the bucket hydraulic cylinder 23 is driven by operating the left or right side to cause the bucket 18 to be clouded or dumped, and the boom hydraulic cylinder 20 is driven by operating the front or rear side to lower the boom. A cross-operated bucket / boom manual operation lever 27R for lowering or raising 14 and a blade lever 31 for driving the blade hydraulic cylinder to move the blade 12 up and down by operating it forward or rearward. Is provided in the right console box 30R. In addition, switches such as a key switch 32 (see FIG. 4 to be described later) and a travel speed changeover switch 33 (see FIG. 4 to be described later) are provided on the upper portion of the right console box 30R.

  In the configuration described above, the left and right crawler belts 1L and 1R, the upper swing body 3, the blade 12, the lower boom 14, the upper boom 15, the arm 17, and the bucket 18 are driven by a hydraulic drive device provided in the hydraulic excavator. This constitutes a driven member. The left / right traveling operation levers 25L, 25R and the blade lever 31 are of a so-called hydraulic pilot type, while the offset operation pedal 26R, the turning / arm operation lever 27L, and the bucket / boom operation lever 27R are This is a so-called electric lever system.

  FIG. 3 is a hydraulic circuit diagram showing a main configuration of a hydraulic drive device related to an electric lever type operation device provided in the hydraulic excavator.

  In FIG. 3, a hydraulic pump 34 driven by an engine (prime mover), and the swing hydraulic motor, the offset hydraulic cylinder 21, the boom hydraulic cylinder 20, the arm hydraulic cylinder 22, and the bucket hydraulic pressure from the hydraulic pump 34. For example, an electric-hydraulic conversion valve type turning control valve 35, an offset control valve 36, and a boom control that respectively control the flow of pressure oil to the cylinder 23 (for convenience, only the hydraulic cylinder 23 for buckets is shown in FIG. 3). An operation including a valve unit 40 including a valve 37, an arm control valve 38, and a bucket control valve 39, and the above-mentioned cross operation type operation lever 27L for instructing a bending operation of the arm 17 and a turning operation of the upper swing body 3. Device 41L and upper and lower of lower boom 14 An operation device 41R having the cross operation type operation lever 27R for instructing the operation and bending operation of the bucket 18, an operation device 42 having the operation pedal 26R for instructing a turning operation of the upper boom 15, and the lock lever. An operating device 43 provided with 29 and a controller 44 are provided.

  The operation devices 41L and 41R include the above-mentioned cross operation type operation levers 27L and 27R that can be displaced in the front-rear direction and the left-right direction, and lever displacement detectors (potentiometers, not shown) that detect the respective displacements. These lever displacement detectors detect the displacement direction (which direction of the cross direction) and the displacement amount (operation amount) of the operation levers 27L and 27R, respectively, and the operation signal (operation command signal) corresponding thereto. ) Is output to the controller 44.

  The operation device 28 includes the operation pedal 27R and a pedal displacement detector (potentiometer, not shown) for detecting the displacement thereof. The pedal displacement detector includes a displacement direction of the operation pedal 27R and a displacement direction of the operation pedal 27R. Each displacement amount is detected, and an operation signal corresponding to the detected amount is output to the controller 44.

  As a first function, the controller 44 performs predetermined arithmetic processing on the operation signals input from the operation devices 41L, 41R, and 42, and uses the generated drive signals (control signals) as turning electromagnetic pressure reducing valves 35A, 35B, The electromagnetic pressure reducing valves 36A and 36B for offset, the electromagnetic pressure reducing valves 37A and 37B for booms, the electromagnetic pressure reducing valves 38A and 38B for arms, and the electromagnetic pressure reducing valves 39A and 39B for buckets are output.

  The electromagnetic proportional valves for turning 35A and 35B, the electromagnetic proportional valves for offset 36A and 36B, the electromagnetic proportional valves for booms 37A and 37B, the electromagnetic proportional valves for arms 38A and 38B, and the electromagnetic proportional valves for buckets 39A and 39B are the controller 44. Based on the drive signal from the pilot pump 28, the pilot pressure of the pilot pump 28 (primary pilot pressure) is reduced to generate the operating pilot pressure, and the pilot operating portion of the turning control valve 35 and the pilot of the offset control valve 36, respectively. Output to the operation section, the pilot operation section of the boom control valve 37, the pilot operation section of the arm control valve 38, and the pilot operation section of the bucket control valve 39, whereby the turning control valve 35 and the offset control valve 36 are output. , Over arm control valve 37, so that the switch the arm control valve 38 and the bucket control valve 39,.

  In addition, a hydraulic shut-off valve 45 is provided in the hydraulic line between the electromagnetic pressure reducing valves 35A, 35B to 39A, 39B and the pilot pump 28 so that the hydraulic line can be communicated and cut off.

  As a second function, the controller 44 performs predetermined arithmetic processing on the operation signal input from the operation device 43 including the lock lever 29 and outputs the generated drive signal (control signal) to the hydraulic pressure cutoff valve 45. It is like that. That is, when the lock lever 29 is pulled down to the release position (lowering position), the operation signal is input from the operation device 43 to the controller 44, and based on this, the drive signal is output from the controller 44 to the hydraulic cutoff valve 45. As a result, the hydraulic cutoff valve 45 is switched to the upper communication position in FIG. 3, and the original pressure from the pilot pump 28 is guided to the electromagnetic pressure reducing valves 35A, 35B to 39A, 39B. On the other hand, when the lock lever 29 is pulled up to the lock position (upward position), the operation signal is input from the operation device 43 to the controller 44, and based on this, a stop signal is output from the controller 44 to the hydraulic pressure cutoff valve 45. As a result, the hydraulic shut-off valve 45 is switched to the shut-off position shown on the lower side in FIG. 3 so that the original pressure from the pilot pump 28 is shut off.

  In such a hydraulic drive device, if a failure or the like of the controller 44 occurs, a hydraulic actuator using the operation levers 37L and 37R and the operation pedal 26R (specifically, the turning hydraulic motor, the boom hydraulic cylinder 20 and the offset hydraulic cylinder 20). Operation of the hydraulic cylinder 21, the arm hydraulic cylinder 22, and the bucket hydraulic cylinder 23) becomes impossible. However, there is a case where it is desired to temporarily perform a minimum necessary operation for the purpose of maintenance work or movement of a hydraulic excavator, for example. The construction machine operating circuit device of the present invention is configured to allow temporary operation of the hydraulic actuator in such a case.

  4 and 5 are electric circuit diagrams showing a schematic configuration of an embodiment of the operation circuit device for the construction machine according to the present invention, and FIGS. 6 and 7 are arrangements of the embodiment of the operation circuit device for the construction machine. It is a perspective view of the front left part on the turning frame 4 showing a layout. 4 and 6 show a normal wiring connection state, and FIGS. 5 and 7 show a wiring connection state for temporary operation.

  4 to 7, the controller 44, the valve unit 40 including the control valves 35 to 39, the valve unit 47 including the hydraulic shut-off valve 45 and a travel speed switching valve 46 described later, and the key switch. 32 and the travel speed change-over switch 33 for instructing switching of the travel speed of the hydraulic excavator. As shown in FIGS. 6 and 7, the valve unit 40 is disposed on the front left side portion (specifically, below the operator cab 6) on the revolving frame 4, and the valve unit 47 is arranged on the valve unit 40. It is arranged on the front side (lower left side in FIGS. 6 and 7).

  The key switch 32 has one terminal connected to the battery (power source) 48. When the key switch 32 is connected to, for example, the other terminal OFF by rotating the operation key, the electric system is turned off and the engine is stopped. For example, when connected to the ON terminal on the other side, the electric system is turned on, and when connected to the START terminal on the other side, for example, the electric system is turned on and the engine is instructed to start.

  The controller 44 is connected to the ON terminal of the key switch 32 via a power supply line 49 so that power from the battery 48 is supplied. In addition, the controller 44 includes a harness 50A in which five sets of signal wires and ground wires for outputting drive signals to the electromagnetic pressure reducing valves 35A to 39A described above are bundled and a 10-pole connector 50Aa is provided at an end thereof. A harness 50B in which five sets of signal wires and ground wires for outputting drive signals to the electromagnetic pressure reducing valves 35B to 39B described above are bundled and a 10-pole connector 50Ba is provided at the end thereof is connected. Each of the electromagnetic pressure reducing valves 35A to 39A is connected to a pair of signal lines and a ground wire, and a two-pole connector 51A is provided at the end thereof, and each of the electromagnetic pressure reducing valves 35B to 39B is set to one set of signal lines. And a two-pole connector 51B is provided at the end thereof.

  Also, a 10-pole connector 52Aa that can be attached to and detached from the 10-pole connector 50Aa on the controller 44 side is provided on one side (left side in FIGS. 4 and 5), and five sets of signal wires and ground wires are connected to the 10-pole connector 52Aa. A harness 52A is provided on the other side (right side in FIG. 4 and FIG. 5) of each of these sets. Then, in a state where the connector 50Aa on the controller 44 side, the connector 52Aa on the harness 52A, the connector 51A on the electromagnetic pressure reducing valves 35A to 39A side, and the connector 52Ab on the harness 52A are connected, the drive signal from the controller 44 is sent to the electromagnetic pressure reducing valve 35A. To 39A.

  Similarly, a 10-pole connector 52Ba that can be attached to and detached from the 10-pole connector 50Ba on the controller 44 side is provided on one side (left side in FIGS. 4 and 5), and five sets of signal wires and ground wires are provided to the 10-pole connector 52Ba. A harness 52B is provided that is connected and provided with a two-pole connector 52Bb that can be attached to and detached from the two-pole connector 51B on the electromagnetic pressure reducing valve 35B to 39B side at the other end (right side in FIGS. 4 and 5) of each set. Yes. Then, in a state where the connector 50Ba on the controller 44 side, the connector 52Ba on the harness 52B, the connector 51B on the electromagnetic pressure reducing valves 35B to 39B side, and the connector 52Bb on the harness 52B are connected, the drive signal from the controller 44 is sent to the electromagnetic pressure reducing valve 35B. To 39B.

  The hydraulic shut-off valve 45 is connected to a pair of power lines and a ground line, and a two-pole connector 53 is provided at the end thereof. Further, a power supply line 54a connected to the ON terminal of the key switch 32 and a ground line 54b connected to the controller 44 are bundled, and a two-pole connector that can be attached to and detached from the two-pole connector 53 on the hydraulic shut-off valve 45 side at its end. A harness 54 provided with a connector 54c is provided. The controller 44 controls the hydraulic shut-off valve 45 in a state where the connector 53 on the hydraulic shut-off valve 45 side and the connector 54c on the controller 44 side are connected.

  The traveling speed changeover switch 33 has one terminal connected to the ON terminal of the key switch 32 via a power line 55. Further, a harness 56 is provided in which a power supply line 56a connected to the other terminal of the travel speed changeover switch 33 and a separately prepared ground line 56b are bundled and a two-pole connector 56c is provided at an end thereof. The traveling speed switching valve 46 is connected to a pair of power lines and a ground line, and a two-pole connector 57 is provided at the end thereof. When the travel speed changeover switch 33 is turned on with the travel speed changeover switch 33 side connector 56c and the travel speed changeover valve 46 side connector 57 being connected, the travel speed changeover valve 46 is energized. By driving, for example, the setting of the displacement of the left / right traveling hydraulic motors 10L, 10R is switched, and the traveling speed is switched.

  As a major feature of the present embodiment, the connector 56c on the traveling speed changeover switch 33 side and the connector 57 on the traveling speed switching valve 46 side are disconnected, and the connectors 50Aa and 50Ba on the controller 44 side and the electromagnetic pressure reducing valves 35A, 35B to 39A. , 39B side connectors 52Aa, 52Ba are disconnected, and the controller 44 side connector 54c and the hydraulic shutoff valve 45 side connector 53 are disconnected. A relay harness 58 and a connection harness 59 (connection circuit means) for connecting any one of the pressure reducing valves 35A, 35B to 39A, 39B are provided. As shown in FIG. 6, the connection position of the connector 56c on the traveling speed changeover switch 33 side and the connector 57 on the traveling speed switching valve 46 side, the connectors 50Aa and 50Ba on the controller 44 side, and the electromagnetic pressure reducing valves 35A, 35B to 39A. , 39B side connectors 52Aa, 52Ba, and the controller 44 side connector 54c and the hydraulic shutoff valve 45 side connector 53 are located close to each other and have good workability (for example, a rotating body frame). 4 is arranged at a position where the hydraulic piping or the like is not densely arranged in the outer portion of 4.

  The relay harness 58 is provided with a 10-pole connector 58a that can be attached to and detached from the connector 52Aa on the electromagnetic pressure reducing valves 35A to 39A side (or the connector 52Ba on the electromagnetic pressure reducing valve 35B to 39B side) on one side (right side in FIGS. 4 and 5). The 10-pole connector 58a is connected to 5 sets of power supply lines and ground wires, and a 2-pole connector 58b is provided at the other end (left side in FIGS. 4 and 5) of each set.

  The connection harness 59 is provided with a two-pole connector 59a that can be attached to and detached from the two-pole connector 56c on the traveling speed changeover switch 33 side on one side, and a pair of power supply wires 59b and a ground wire 59c are connected to the two-pole connector 59a. Branch wiring is made so that there are two sets, and the other end of each set can be attached to a two-pole connector 59d that can be attached to and detached from the two-pole connector 58b of the relay harness 58 and a two-pole connector 53 on the hydraulic shut-off valve 45 side A two-pole connector 59e is provided.

  Then, the electromagnetic pressure reducing valve 35B-39B side connector 52Ba (or the electromagnetic pressure reducing valve 35A-39A side connector 52Aa) and the connector 58a of the relay cable 58 are connected, and any one of the five connectors 58b of the relay cable 58 is selected. Are connected to the connector 59d of the connection harness 59, the connector 59e of the connection harness 59 is connected to the connector 53 on the hydraulic shut-off valve 45 side, and the connector 59a of the connection harness 59 and the connector 56c on the travel speed changeover switch 33 side are connected. In the connected state (see FIGS. 5 and 7), when the traveling speed changeover switch 33 is operated to the ON state, the hydraulic cutoff valve 45 is energized and switched to the communication position, and the electromagnetic pressure reducing valve corresponding to the selected connector 58b. Is energized and driven to generate a predetermined operating pilot pressure to the control valve. It has become.

  Next, the operation and effect of this embodiment will be described.

  For example, when performing excavation work or the like, when the operator first operates the lock lever 29 to the release position, the operation signal is input to the controller 44, and the controller 44 controls the hydraulic shut-off valve 45 based on this. Thereby, the hydraulic cutoff valve 45 is switched to the communication position, and the original pressure from the pilot pump 28 is introduced into the electromagnetic pressure reducing valves 35A, 35B to 39A, 39B. For example, when the operator operates the operation levers 27L and 27R or the operation pedal 26R with the intention of raising and lowering the work implement 5 and turning operation of the upper swing body 3, the operation signal is input to the controller 44, and based on this. A drive signal generated by the controller 44 is output to the electromagnetic pressure reducing valves 35A to 39A via the harnesses 50A and 52A or to the electromagnetic pressure reducing valves 35B to 39B via the harnesses 50B and 52B. As a result, the electromagnetic pressure reducing valves 35A, 35B to 39A, 39B are driven to control the operation pilot pressure to the control valves 35 to 39, and the hydraulic pump 34 controls the hydraulic actuator (specifically, the above-described turning hydraulic motor, boom boom). The flow of pressure oil to the hydraulic cylinder 20, the offset hydraulic cylinder 21, the arm hydraulic cylinder 22, and the bucket hydraulic cylinder 23) is controlled. In this way, normally, the hydraulic actuator is driven according to the operation of the operation levers 27L, 27R and the operation pedal 26R.

  On the other hand, for example, even if a failure of the controller 44 occurs, there is a case where it is desired to perform the minimum necessary operation of the work machine 5. In such a case, the connector 56c on the traveling speed switching switch 33 side and the connector 57 on the traveling speed switching valve 46 side are disconnected, and the connectors 50Aa and 50Ba on the controller 44 side and the connectors on the electromagnetic pressure reducing valves 35A, 35B to 39A and 39B side are separated. 52Aa, 52Ba, the connector 54c on the controller 44 side, and the connector 53 on the hydraulic shutoff valve 45 side are disconnected. Then, the connector 59a of the connection harness 59 and the connector 56c on the traveling speed changeover switch 33 side are connected, and the connector 59e of the connection harness 59 and the connector 53 on the hydraulic shutoff valve 45 side are connected. Then, an electromagnetic pressure reducing valve (any one of 35A, 35B to 39A, 39B) corresponding to the operation of the desired hydraulic actuator is selected, and the electromagnetic pressure reducing valves 35B to 39B side corresponding to the selected electromagnetic pressure reducing valve The connector 52Ba (or the connector 52Aa on the electromagnetic pressure reducing valve 35A to 39A side) and the connector 58a of the relay cable 58 are connected, and one of the five connectors 58b of the relay cable 58 and the connector 59d of the connection harness 59 are connected. Connecting. As a result, when the operator operates the travel speed changeover switch 33 to the ON state, the selected electromagnetic pressure reducing valve and hydraulic pressure cutoff valve 45 are energized and driven to generate a predetermined operating pilot pressure to the control valve. As a result, the minimum necessary operations of the work machine 5 and the swing body 3 can be performed.

  As described above, in the present embodiment, the travel speed changeover switch 33 that operates the travel speed changeover valve 46 without using the controller 44 is used, and instead of the travel speed changeover valve 46, the operation of a desired hydraulic actuator is supported. By connecting the electromagnetic pressure reducing valve and the hydraulic cutoff valve 45 using the relay harness 58 and the connection harness 59, the temporary operation of the hydraulic actuator can be performed. In addition, since the operation of a plurality of hydraulic actuators can be handled by switching the electromagnetic pressure reducing valve connected to the travel speed changeover switch 33, a switch is prepared corresponding to all electric lever type operation devices as in the prior art. This eliminates the need to provide a new dedicated switch since an existing switch is used. Therefore, the temporary operation of the hydraulic actuator can be performed while reducing cost and installation space.

  Further, for example, the plurality of two-pole connectors 51A, 51B provided on the electromagnetic pressure reducing valves 35A, 35B to 39A, 39B and the plurality of two-pole connectors 52Ab, 52Bb of the harnesses 52A, 52B are disconnected, and the plurality of two-pole connectors 51A are separated. , 51B and the configuration in which the two-pole connector 59d of the connection harness 59 is connected, the same effect as in the above embodiment can be obtained. However, for example, the positions of the plurality of connectors 51A and 51B are dispersed corresponding to the electromagnetic pressure reducing valves 35A, 35B to 39A and 39B, respectively, or the hydraulic piping connected to the electromagnetic pressure reducing valves 35A, 35B to 39A and 39B, for example. For reasons such as being densely packed, it may be difficult to disconnect and connect the connectors 51A and 51B. In the present embodiment, by using the relay harness 58, it is possible to perform disconnection and connection work with the 10-pole connectors 52Aa and 52Ba of the harnesses 52A and 52B, and the connectors 52Aa and 52Ba and the relay harness 58 are easy to work. It is possible to improve the workability by arranging at the position.

  In the first embodiment, the travel speed switching in which one terminal is connected to the battery 48 via the key switch 32 or the like and the other terminal is connected to the travel speed switching valve 46 without using the controller 44. Although the switch 33 has been described as an example, the present invention is not limited to this. That is, as long as it is a switch connected to the battery 48 without passing through the controller 44, for example, a horn switch for instructing horn sounding or a light switch for instructing light illumination may be used. In such a case, the same effect as described above can be obtained.

  A second embodiment of the present invention will be described with reference to FIGS. This embodiment is an embodiment in which a desired electromagnetic pressure reducing valve (any one of 35A, 35B to 39A, 39B) and a hydraulic pressure cutoff valve 45 are connected to two switches, respectively.

  8 and 9 are electric circuit diagrams showing a schematic configuration of the operation circuit device of the construction machine according to the present embodiment, FIG. 8 shows a normal wiring connection state, and FIG. 9 shows a wiring connection state for temporary operation. To express. 8 and 9, the same reference numerals are given to the same parts as those in the above embodiment, and the description will be omitted as appropriate.

  In the present embodiment, a horn 60 and, for example, a horn switch 61 that is provided in a grip portion of the turning / arm manual operation lever 27L and instructs the horn 60 to sound are provided. The horn switch 61 has one terminal connected to the ON terminal of the key switch 32 via a power line 62. Further, a harness 63 is provided in which a power supply line 63a connected to the other terminal of the horn switch 61 and a separately prepared ground line 63b are bundled and a two-pole connector 63c is provided at an end thereof. The horn 60 is connected to a pair of power supply lines and a ground line, and a two-pole connector 64 is provided at the end thereof. When the horn switch 61 is operated in the ON state with the connector 63c on the horn switch 61 side and the connector 64 on the horn 60 side connected, the horn 60 is energized and driven to blow.

  As a major feature of this embodiment, the connector 63c on the horn switch 61 side and the connector 53 on the hydraulic shut-off valve 45 side are detachable. Further, a connection harness 65 for connecting the other terminal of the travel speed changeover switch 33 and the relay harness 58 is provided. The connection harness 65 is provided with a two-pole connector 65a that can be attached to and detached from the two-pole connector 56c on the traveling speed changeover switch 33 side on one side, and a pair of power supply lines 65b and a ground wire 65c are connected to the two-pole connector 65a. A two-pole connector 65d that can be attached to and detached from the two-pole connector 58b of the relay harness 58 is provided at the other side end.

  When the horn switch 61 is operated in the ON state while the connector 53c on the hydraulic shutoff valve 45 side and the connector 63c on the horn switch 61 side are connected, the hydraulic shutoff valve 45 is energized and switched to the communication position. The original pressure from the pump 28 is introduced into the electromagnetic pressure reducing valves 35A, 35B to 39A, 39B. Further, an electromagnetic pressure reducing valve (any one of 35A, 35B to 39A, 39B) corresponding to the operation of the desired hydraulic actuator is selected, and the electromagnetic pressure reducing valves 35B to 39B side corresponding to the selected electromagnetic pressure reducing valve The connector 52Ba (or the connector 52Aa on the electromagnetic pressure reducing valve 35A to 39A side) and the connector 58a of the relay cable 58 are connected, and one of the five connectors 58b of the relay cable 58 and the connector 65d of the connection harness 65 are connected. Then, the connector 65a of the connection harness 65 and the connector 56c on the traveling speed changeover switch 33 side are connected. When the operator operates the travel speed changeover switch 33 to the ON state, the selected electromagnetic pressure reducing valve is energized and driven, and a predetermined operation pilot pressure to the control valve is generated. As a result, the minimum necessary operation of the hydraulic actuator can be performed.

  In the present embodiment configured as described above, the temporary operation of the hydraulic actuator can be performed while reducing the cost and the installation space as in the above-described one embodiment.

  In the second embodiment, the case where the connector 63c on the horn switch 61 side and the connector 53 on the hydraulic shutoff valve 45 side are directly connected has been described as an example. However, the present invention is not limited to this. You may connect. In this case, the same effect as described above can be obtained.

It is a side view showing the whole structure of the small hydraulic excavator which is an application object of the present invention. It is the arrow overhead view seen from the arrow II direction in FIG. It is a circuit diagram showing the principal part structure of the hydraulic drive apparatus regarding the operating device of the electric lever system with which the hydraulic shovel which is the application object of this invention was equipped. It is an electrical circuit diagram showing the schematic structure of 1st Embodiment of the operation circuit apparatus of the construction machine of this invention, and represents a normal wiring connection state. It is an electric circuit diagram showing the schematic structure of 1st Embodiment of the operation circuit apparatus of the construction machine of this invention, and represents the wiring connection state for temporary operation. It is a perspective view of the front left side part on the turning frame showing the arrangement layout of the first embodiment of the operation circuit device of the construction machine of the present invention, and represents a normal wiring connection state. It is a perspective view of the front left side part on the turning frame showing the arrangement layout of the first embodiment of the operation circuit device of the construction machine of the present invention, and represents the wiring connection state for temporary operation. It is an electric circuit diagram showing schematic structure of 2nd Embodiment of the operation circuit apparatus of the construction machine of this invention, and represents a normal wiring connection state. It is an electric circuit diagram showing the schematic structure of 2nd Embodiment of the operation circuit apparatus of the construction machine of this invention, and represents the wiring connection state for temporary operation.

Explanation of symbols

2 Lower traveling body 3 Upper turning body 5 Working machine 20 Boom hydraulic cylinder 21 Offset hydraulic cylinder 22 Arm hydraulic cylinder 23 Bucket hydraulic cylinder 26R Offset operation pedal (operation means)
27L Rotation / arm operation lever (operation means)
27R Operation lever for bucket boom
33 Traveling speed changeover switch 34 Hydraulic pump 35-39 Control valve 35A, 35B-39A, 39B Electromagnetic pressure reducing valve 44 Controller 45 Hydraulic shutoff valve 46 Traveling speed changeover valve (electronic component)
48 Battery (Power)
58 Relay harness (connection circuit means)
59 Connection harness (connection circuit means)
60 Horn (electronic parts)
61 Horn switch 63 Harness (connection circuit means)
65 Connection harness (connection circuit means)

Claims (4)

A lower traveling body, an upper revolving body provided on the lower traveling body so as to be capable of swiveling, an articulated working machine provided on the upper revolving body so as to be able to be raised and lowered, and a plurality of hydraulic actuators for driving the working machine; A hydraulic pump, a plurality of hydraulic pilot type control valves that control the flow of pressure oil from the hydraulic pump to the hydraulic actuator, a plurality of electromagnetic pressure reducing valves that generate operating pilot pressure to the control valve, An operation circuit device for a construction machine, comprising: a hydraulic shut-off valve capable of shutting off a source pressure supplied to the plurality of electromagnetic pressure reducing valves; and a controller for controlling the hydraulic shut-off valve and the plurality of electromagnetic pressure reducing valves according to operation of an operating means In
Without passing through the controller, a switch in which one terminal is connected to a power source and the other terminal is connected to an electronic component;
Disconnecting the other terminal of the switch and the electronic component and disconnecting the controller, the hydraulic shut-off valve and the electromagnetic pressure reducing valve, respectively, the other terminal of the switch and the hydraulic shut-off valve and An operation circuit device for a construction machine, comprising connection circuit means capable of connecting to each of the electromagnetic pressure reducing valves.   2. The operation circuit device for a construction machine according to claim 1, wherein the connection circuit means includes a connector detachably attached to the switch side connector, the connector detachable to the hydraulic shutoff valve side connector, and the electromagnetic An operation circuit device for a construction machine, comprising a connection harness having a detachable connector on the other side of the connector on the pressure reducing valve side.   2. The construction machine operation circuit device according to claim 1, comprising a plurality of said switches, wherein said connection circuit means connects said one switch side connector and said hydraulic shut-off valve side connector to said other switch side. An operation circuit device for a construction machine, wherein the connector on the electromagnetic pressure reducing valve side is connected.   The operation circuit device for a construction machine according to claim 2 or 3, wherein the connection circuit means is provided with one connector detachably attached to one connector connected to the plurality of electromagnetic pressure reducing valves on the one side, An operation circuit device for a construction machine, comprising a relay harness provided on the other side with a plurality of connectors each corresponding to an electromagnetic pressure reducing valve.

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