JP2010065445A - Electric working machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric working machine, restraining a power cable from getting twisted around a revolving structure or a traveling body even when sagging is caused in the power cable. <P>SOLUTION: This electric hydraulic shovel 1 includes: a self-running traveling body 10; an electric motor 24 rotatably mounted on the traveling body 10 and supplied with power by an external power supply 50; the revolving structure 20 provided with a hydraulic pump 25 driven by the electric motor 24; and a cable arm 60 provided on the revolving structure 20 to be rotated along a plane including a revolving frame 21 of the revolving structure 20 and holding the power supply cable 51 for supplying power to the electric motor 24. The shape and dimensions of the cable arm 60 are set so that a turning locus drawn by an outermost holding part 60c, which is a holding part provided on the cable arm 60 and located at the outmost side in the holding part of the power supply cable 51 electric working machine, is outside the revolving structure 20 and the traveling body 10. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electric work machine such as an electric hydraulic excavator that holds a power cable connected to an external power source and includes a cable arm that is rotatable along a plane including a turning frame.

  There exists a thing shown by patent document 1 as this type of prior art. This prior art is an electric hydraulic excavator, and includes a self-propelled traveling body, a motor that is turnably mounted on the traveling body, and that is powered by an external power source, and a hydraulic pump that is driven by the motor. The swivel body and the swivel body are provided on the swivel body so as to be rotatable along a plane including the swivel frame of the swivel body, and include a guide arm that holds a power cable for supplying power to the electric motor, that is, a cable arm. Yes. The holding part located on the outermost side among the holding parts of the power cable of the cable arm is arranged immediately above the counterweight provided in the swivel body.

The prior art also includes a reel on which the power cable held by the cable arm is wound, and tension applying means for applying tension to the power cable so as not to cause slack in the power cable wound on the reel. It has a configuration with.
Japanese Patent No. 2938774

  In the above-described prior art, the outermost holding portion of the power cable holding portion of the cable arm is disposed immediately above the counterweight. When slack is generated in the wound power cable, the power cable may be entangled with the swivel body or the traveling body. When such a power cable entanglement occurs, the excavation work and the like carried out with this electric hydraulic excavator are temporarily interrupted, and a complicated work to unwind the power cable becomes necessary. The efficiency of work done is reduced.

  The present invention has been made from the actual situation in the above-described prior art, and the object thereof is to prevent the power cable from being entangled with the revolving body or the traveling body even when the power cable is slack. It is to provide an electric work machine.

  To achieve this object, an electric work machine according to the present invention is a self-propelled traveling body, a motor that is turnably mounted on the traveling body, and that is powered by an external power source, and is driven by the motor. A revolving body provided with a hydraulic pump, and a cable arm that is provided on the revolving body so as to be rotatable along a plane including a revolving frame of the revolving body and holds a power cable for supplying power to the electric motor. In the electric work machine, the shape and dimensions of the cable arm are determined by the rotation trajectory drawn by the outermost holding portion that is the outermost holding portion of the power cable holding portion provided in the cable arm, It is characterized by being set to be outside the revolving body and the traveling body.

  According to the present invention configured as described above, the rotation trajectory drawn by the outermost holding portion accompanying the rotation of the cable arm, that is, the rotation of the portion of the cable arm positioned on the outermost side of the portion holding the power cable is rotated. Since the movement trajectory is located outside the swing body and the traveling body, the power cable contacts the swing body and the traveling body even when the power cable held by the cable arm is slack and hangs down. You can avoid the situation. Thereby, it can suppress that a power supply cable gets entangled with a turning body or a traveling body.

  The electric work machine according to the present invention is the electric work machine according to the present invention, wherein the cable arm is inclined with respect to the revolving frame, and a rotation fulcrum provided at a lower end of the inclined portion. And the outermost holding portion is provided at the upper end of the inclined portion. In the present invention configured as described above, most of the cable arm can be configured by the inclined portion, and if configured in this way, the length dimension of the cable arm can be shortened.

  In the electric work machine according to the present invention, in the above invention, the revolving body is provided with a bearing that rotatably holds the shaft portion of the cable arm, and the shaft portion of the cable arm is provided with the bearing. It is characterized by providing a collar portion that is in sliding contact with. According to the present invention configured as described above, the cable arm can be stably rotated by the sliding contact between the collar portion provided on the shaft portion of the cable arm and the bearing provided on the swivel body.

  The electric work machine according to the present invention is characterized in that, in the above invention, the cable arm is provided with a camera capable of photographing the power cable held by the outermost holding portion. According to the present invention configured as described above, the state of the power cable held by the outermost holding portion of the cable arm can be monitored by the image of the camera.

  Moreover, the electric work machine according to the present invention is characterized in that, in the above-mentioned invention, a rotating electric motor for rotating the cable arm is provided. In the present invention configured as described above, when the power cable is likely to be entangled with the revolving body or the traveling body, the electric motor for rotation is operated to rotate the cable arm left and right, for example, and swing the power cable left and right. This power cable can be handled automatically so as not to get tangled.

  According to the present invention, the shape and dimension of a cable arm that holds a power cable connected to an external power source and that supplies power to an electric motor provided in a swivel body is positioned on the outermost side of the holding portion of the power cable provided in the cable arm Since the rotation trajectory drawn by the outermost holding part, which is the holding part, is set to be outside the revolving body and the traveling body, even when the power cable is slack, It is possible to suppress the entanglement of the revolving body or the traveling body, to reduce the interruption of the work performed by the electric work machine, and to improve the work efficiency as compared with the prior art.

  Hereinafter, the best mode for carrying out an electric work machine according to the present invention will be described with reference to the drawings.

  FIG. 1 is a side view showing a first embodiment of an electric work machine according to the present invention, FIG. 2 is a plan view of the first embodiment shown in FIG. 1, and FIG. 3 is a schematic diagram of a drive system provided in the first embodiment. FIG. 4 is a diagram showing a cable arm mounting structure provided in the first embodiment, FIG. 5 is a block diagram showing a main part of a control system provided in the first embodiment, and FIG. It is a figure which shows the image image | photographed with the camera with which embodiment is equipped.

  The electric work machine according to the present invention is, for example, an electric hydraulic excavator as shown in FIGS. 1 and 2, and a crawler type traveling body 10 and a turn mounted on the traveling body 10 via a turning device 30. A body 20, a work machine mounted on the revolving body 20 so as to be rotatable in the vertical direction, that is, a work front 40 is provided.

  The traveling body 10 includes a track frame 11, left and right crawler belts 12a and 12b provided on the track frame 11, and left and right traveling motors 13a and 13b for driving the crawler belts 12a and 12b, respectively. The swivel body 20 is provided at a swivel frame 21 formed as a support structure, a counterweight 22 provided at the rear end portion of the swivel frame 21, and a front side position of the swivel frame 21. A cab 23 for operation and a power unit chamber 26 in which various devices such as an electric motor 24 and a hydraulic pump 25 described later are stored are provided.

  The work front 40 has a boom 45 provided on the revolving structure 20 so as to be rotatable in the vertical direction, an arm 46 provided at the tip of the boom 45 so as to be rotatable in the vertical direction, and a vertical direction at the tip of the arm 46. And a bucket 47 that is rotatably provided. Various attachments may be attached instead of the bucket 47.

  As shown in FIG. 3, the electric motor 24 accommodated in the power unit chamber 26 is composed of, for example, an electric motor driven by a three-phase alternating current, and is supplied with power from an external power supply 50 via a power cable 51 and a control device 52. As a result, the hydraulic pump 25 is driven. The flow of pressure oil from the hydraulic pump 25 is controlled by the control valve 28, and the hydraulic motors that drive the traveling motors 13 a and 13 b, the turning motor included in the turning device 30, the boom 45, the arm 46, and the bucket 47 of the work front 40. It is supplied to and discharged from a cylinder. The control device 52 described above is disposed, for example, in the cab 23, and is activated or demagnetized by the start / stop switch 52a provided in the vicinity of the driver's seat of the cab 23 and the start / stop switch 52a. And an electromagnetic circuit breaker 52b for controlling a power supply state to the electric motor 24.

  Moreover, as shown in FIGS. 1 and 2 described above, a cable arm 60 that holds a power cable 51 that supplies power to the electric motor 24 is provided in the vicinity of the rear end portion of the revolving structure 20. As shown in FIG. 2, the shape and dimension of the cable arm 60 is such that the outermost holding portion 60c, which is the outermost holding portion of the holding portion of the power cable 51 provided in the cable arm 60, is drawn. The movement trajectory is set to be outside the revolving structure 20 and the traveling structure 10.

  For example, as shown in FIG. 4, the cable arm 60 is provided with an inclined portion 60 a extending in an inclined manner with respect to the turning frame 21 of the turning body 20, and is provided at the lower end of the inclined portion 60 a and rotates. It has a shaft portion 60b that forms a fulcrum and extends in the vertical direction, and the outermost holding portion 60c described above is provided at the upper end of the inclined portion 60a. As shown in FIG. 1, most of the cable arm 60 is constituted by an inclined portion 60a.

  As shown in FIG. 4, the revolving unit 20 is provided with a bearing 62 that rotatably holds the shaft portion 60 c of the cable arm 60, and the shaft portion 60 b of the cable arm 60 is in sliding contact with the bearing 62. A collar portion 60d is provided.

  Further, a camera 61 capable of photographing the power cable 51 held by the outermost holding portion 60c is attached in the vicinity of the outermost holding portion 60c of the cable arm 60. As shown in FIG. 5, a signal output from the camera 61 is transmitted to, for example, a control device 80 disposed in the cab 23 and is subjected to signal processing by a camera image generation unit 80a included in the control device 80. As shown in FIG. 6, for example, it is displayed on the screen of a display 66 arranged in the cab 23.

  The electric excavator 1 according to the first embodiment configured as described above operates the start / stop switch 52a of the control device 52 shown in FIG. By supplying power to the electric motor 24 via 52, the hydraulic pump 25 is driven as described above. In this state, by switching the direction control valve included in the control valve 28, the pressure oil discharged from the hydraulic pump 25 causes the traveling motors 13a and 13b, the turning motor, or the hydraulic cylinder that drives the work front 40 to move. It is supplied to the corresponding hydraulic actuator, and the traveling body 10 travels, the revolving body 20 revolves, or the work front 40 performs work. Further, the state of the power cable 51 photographed by the camera 61 and held by the cable arm 60 is displayed on the display 66 of the cab 23.

  The operator in the cab 23 looks at the screen of the display 66, and when there is a concern that the power cable 51 may come into contact with the revolving unit 20 or the traveling unit 10, the cable arm 60 is manually operated in advance, for example, left and right The power cable 51 is swung to the left and right, and the power cable 51 can be dealt with so as not to contact the revolving structure 20 and the traveling body 10.

  According to the first embodiment, as shown in FIG. 2, the rotation trajectory drawn by the outermost holding portion 60 c accompanying the rotation of the cable arm 60, that is, of the portion holding the power cable 51. Since the rotation trajectory of the portion of the cable arm 60 located on the outermost side is located outside the revolving unit 20 and the traveling unit 10, the power cable 51 held by the cable arm 60 is slackened and seems to hang down. Even in such a case, it is possible to avoid a situation in which the power cable 51 contacts the revolving unit 20 and the traveling unit 10. Thereby, it can suppress that the power cable 51 gets entangled with the revolving body 20 or the traveling body 10, the interruption of the work performed by this electric hydraulic excavator 1 can be reduced, and the work efficiency can be improved.

  Further, since most of the cable arm 60 is constituted by the inclined portion 60a, for example, the cable arm 60 has a shaft portion 60b that extends sufficiently long upward, and a horizontal extension that is connected to the shaft portion 60b. The length of the cable arm 60 can be shortened as compared with the configuration in which the outermost holding portion 60c is provided at the tip of the horizontal extending portion. Costs required can be reduced.

  Further, as shown in FIG. 4, the cable arm 60 can be stably rotated by sliding contact between the shaft portion 60 b of the cable arm 60 and the bearing 62 provided on the swivel body 20, so that reliability is ensured. A high-powered electric excavator 1 can be realized.

  Further, as shown in FIG. 6, the state of the power cable 51 held by the outermost holding portion 60 c of the cable arm 60 can be monitored by a photographed image of the camera 61. Therefore, when the operator who looks at the screen of the display 66 determines that the power cable 51 is likely to be entangled with the revolving structure 20 or the traveling body 10, it is possible to take measures in advance so that the power cable 51 is not entangled.

  FIG. 7 is a view showing a mounting structure of a cable arm constituting the main part of the second embodiment of the present invention, FIG. 8 is a view for explaining a control system provided in the second embodiment, and FIG. The figure which shows the cable arm operation switch with which a control system is equipped, The figure (b) is a block diagram which shows the principal part of this control system.

  As shown in FIG. 7, the electric excavator 1 according to the second embodiment includes a gear 63 a integrally provided on the shaft portion 60 b of the cable arm 60, a gear 63 b that meshes with the gear 63 a, and the swivel body 20. An electric motor that is provided on the fixed bracket 64 and rotates the gear 63 b, that is, a rotating electric motor 65 that rotates the cable arm 60 is provided.

  Further, in the cab 23, as shown in FIG. 8A, a cable arm operation switch 70 for rotating the cable arm 60 left and right is provided. Further, a drive signal generation unit 80b that outputs a control signal to the motor driver 82 that drives the electric motor 65 for rotation according to the signal of the cable arm operation switch 70 to the control device 80 arranged in the cab 23. Is included. Other configurations are the same as those of the first embodiment described above.

  In the second embodiment configured as described above, the same effect as that of the first embodiment can be obtained, and when the power cable 51 is likely to be entangled with the swing body 20 or the traveling body 10, the cable arm operation switch 70 is set. The motor driver 82 is operated to output a control signal from the drive signal generation unit 80b of the control device 80, the electric motor 65 for rotation is driven by the motor driver 82, and the shaft portion of the cable arm 60 is connected via the gears 63b and 63a. The power cable 51 can be swung left and right by rotating the cable arm 60 left and right by rotating the b 60b, and it is possible to automatically cope with the power cable 51 so that it does not get tangled. Since such an operation can be performed without the operator getting out of the cab 23, even if the operation is interrupted, the interruption can be completed in a short time.

  In addition, when displaying the photographed image of the power cable 51 by the camera 61 on the screen of the display 66, it may be displayed on the screen of the display 66 at all times during various operations performed by the electric excavator 1. In addition, the electric excavator 1 may be displayed on the screen of the display 66 only when the electric excavator 1 is started, turned, or traveled.

  In addition, a monitor that is normally disposed in the cab 23 of this type of electric excavator 1 and displays various pieces of equipment information, work information, and the like may also be used as the display 66 described above.

  Further, the control device 52 including the start / stop switch 52a and the power shut-off device 52b and the control device 80 including the camera image generation unit 80a or including the camera image generation unit 80a and the drive signal generation unit 80b are 1 It may be housed in one box and the box placed in the cab 23.

  Further, if necessary, in addition to the configurations of the first and second embodiments, the reel around which the power cable 51 as described in the above-described prior art is wound and the power cable 51 wound around this reel are loosened. It is also possible to employ a configuration including tension applying means for applying tension to the power supply cable 51 so as not to cause the problem.

1 is a side view showing a first embodiment of an electric work machine according to the present invention. It is a top view of 1st Embodiment shown in FIG. It is a circuit diagram which shows the principal part of the drive system with which 1st Embodiment is equipped. It is a figure which shows the attachment structure of the cable arm with which 1st Embodiment is equipped. It is a block diagram which shows the principal part of the control system with which 1st Embodiment is equipped. It is a figure which shows the image image | photographed with the camera with which 1st Embodiment is equipped. It is a figure which shows the attachment structure of the cable arm which comprises the principal part of 2nd Embodiment of this invention. It is a figure explaining the control system with which 2nd Embodiment is equipped, (a) The figure shows the cable arm operation switch with which this control system is equipped, (b) The figure shows the block which shows the principal part of this control system FIG.

Explanation of symbols

1 Electric excavator (Electric work machine)
DESCRIPTION OF SYMBOLS 10 Traveling body 20 Revolving body 21 Turning frame 23 Operation room 24 Electric motor 25 Hydraulic pump 26 Power unit room 40 Work front 45 Boom 46 Arm 47 Bucket 50 External power supply 51 Power cable 52 Control device 52a Start / stop switch 52b Electromagnetic breaker 60 Cable arm 60a Inclined part 60b Shaft part 60c Outermost holding part 60d Collar part 61 Camera 62 Bearing 63a Gear 63b Gear 64 Bracket 65 Electric motor for rotation 66 Display 70 Cable arm operation switch 80 Controller 80a Camera image generation part 80b Drive signal generation part 82 Motor driver

Claims (5)

Includes a self-propelled traveling body, a revolving body mounted on the traveling body so as to be able to turn and powered by an external power source, a revolving body provided with a hydraulic pump driven by the electric motor, and a revolving frame of the revolving body In the electric working machine provided with the cable arm that is provided in the revolving body so as to be rotatable along a flat surface and holds a power cable for supplying power to the electric motor,
The rotational trajectory drawn by the outermost holding portion, which is the outermost holding portion of the power cable holding portion provided on the cable arm, indicates the shape and dimensions of the cable arm. An electric work machine characterized by being set to be outside the body. The electric work machine according to claim 1,
The cable arm has an inclined portion extending in an inclined manner with respect to the revolving frame, and a shaft portion that is provided at a lower end of the inclined portion and serves as a rotation fulcrum, and the outermost holding portion is An electric working machine provided at an upper end of an inclined portion. The electric work machine according to claim 2,
While providing a bearing for rotatably holding the shaft portion of the cable arm on the swivel body,
An electric work machine characterized in that a collar portion slidably contacting the bearing is provided on the shaft portion of the cable arm. The electric work machine according to claim 1,
An electric work machine, wherein the cable arm is provided with a camera capable of photographing the power cable held by the outermost holding portion. The electric work machine according to claim 1,
An electric work machine comprising a rotating electric motor for rotating the cable arm.

Images