JP4296068B2 - Failure detection device for aerial work platforms - Google Patents

Description

  The present invention provides an aerial work vehicle having an outrigger that is provided with a boom that can freely move up and down, turn, and extend on a vehicle body that can travel, and that is configured to extend and retract to the side of the vehicle body and below the vehicle body in order to stably support the vehicle body. The present invention relates to a failure detection apparatus.

  Outriggers for stably supporting the vehicle body at the time of working at high places are attached to the front, rear, left and right sides of the vehicle body of an aerial work vehicle equipped with booms that can freely move up and down, turn and extend on the vehicle body as described above. This outrigger is composed of an outrigger beam that is inserted into the vehicle body and can expand and contract toward the side of the vehicle body, and a jack attached to the tip of the outrigger beam, and each outrigger beam is extended to the side of the vehicle body. In this state, the vehicle body can be stably supported against the boom moment acting from the boom side to the vehicle body side by extending the jack to the lower side of the vehicle body and lifting the vehicle body in the state.

  The boom moment acting on the vehicle body changes according to the load acting on the boom tip and the movement of the boom tip position due to the boom up and down movement, etc. The size varies depending on the extension amount of the outrigger beam (outrigger tension). For this reason, in an aerial work vehicle equipped with an outrigger as described above, in order to stably lift and support the vehicle body, a boom operation range restricting means for restricting the boom operation range according to the extension amount of the outrigger beam is provided. It has been.

  By the way, in order to appropriately control the boom operating range, it is necessary to accurately detect the extension amount of the outrigger beam. As an extension amount detection device for detecting the extension amount of the outrigger beam, for example, each outrigger beam Some use a provided potentiometer. In the detection device having such a configuration, it is detected whether or not the extension amount detection device has failed in order to prevent improper regulation of the boom operation range due to a malfunction due to a malfunction of the detection device. It is necessary to provide a failure detection device. As a conventionally used failure detection device, an extension amount detection device for failure detection is further attached to each outrigger beam, and the extension value detection is performed by comparing the detection values by these extension amount detection devices. A so-called dual sensor is used to determine whether or not the device is malfunctioning.

  However, if the so-called double sensor as described above can detect the failure of the extension amount detection device, in addition to the extension amount detection device, an extension amount detection device for failure detection is duplicated in each extension amount detection device. Since it is necessary to provide the detection device, there is a problem that the number of detection devices to be attached is increased and the cost is increased. Therefore, instead of detecting the failure by the double sensor as described above, it is possible to detect a failure of the extension amount detection device at a low cost, and an appropriate boom operating range when the extension amount detection device of the outrigger beam fails. There has been a demand to provide a failure detection device that can be regulated.

  In view of the above problems, the present invention detects the failure of the extension amount detection device with the failure detection device having a low-cost configuration, and regulates the operation of the boom when the extension amount detection device fails, thereby stabilizing the vehicle body. It is an object of the present invention to provide a failure detection device for an aerial work vehicle that achieves high performance.

In order to solve the above-described problems, the failure detection device for an aerial work vehicle according to the present invention includes a plurality of lifts that support a vehicle body that is disposed to extend and retract toward the side of the vehicle body in front, rear, left, and right of the vehicle body that can travel. A failure detection device for an aerial work vehicle having an outrigger, and a plurality of extension amount detection means (for example, an extension amount detector A21 in the embodiment) provided at each outrigger and detecting an extension amount of the outrigger to the side of the vehicle body. , An extension amount detector B21 ′ and an extension amount detector C22), on which the extension amount detection means detects the extension amount of each outrigger (for example, the extension amount in the embodiment). a detector A21 and extension amount detector B21'), second expansion amount detecting means for detecting a total expansion amount of a plurality of outriggers (e.g., configured from the expansion amount detector C22) and in the embodiment, is Furthermore, a calculation means for determining that one of the calculation means (for example, the calculation circuit 31 in the embodiment) for calculating the sum of the detection values by the first extension amount detection means and the extension amount detection means has failed. The storage means (for example, the storage circuit 32 in the embodiment) that stores the difference between the calculated value obtained by the above and the detection value obtained by the second expansion amount detection means in advance, and the calculated value obtained by the arithmetic means and the second expansion amount detection means. When the difference from the detected value exceeds the set value stored in the storage means, it has failure determination means (for example, the failure determination circuit 33 in the embodiment) that determines that one of the expansion amount detection means has failed. .

In order to solve the above-described problems, a failure detection apparatus for an aerial work vehicle according to the present invention includes a proximal end member and a distal end side member that are nested in a vehicle body that can travel and a distal end member (for example, an outrigger in the embodiment). A working device (for example, an outrigger 8 in the embodiment) in which the beam 10 and the distal boom 5c) are movably attached to the proximal end member (for example, the vehicle body 2 and the proximal boom 5a in the embodiment) in the longitudinal axis direction. A failure detection apparatus for an aerial work vehicle having a boom 5), which is attached to one of a base end side member and a front end side member and is capable of winding and unwinding freely (for example, an embodiment) And the other member of the proximal end side member and the distal end side member. The attached sheave to which the extension amount detection wire fed out from the extension amount detecting means is wound, and the extension amount detection that is attached to one member of the base end side member and the distal end side member and hung around the sheave The tip of the wire is locked, and angle detection means (for example, the angle detector 26 in the embodiment) for detecting the extending direction angle of the extension amount detection wire is provided.

  Further, in the failure detection device for an aerial work vehicle having the above-described configuration, the angle detection unit is configured such that the wire is wound and fed out from the extension amount detection unit according to the movement of the distal end side member in the longitudinal axis direction with respect to the proximal end side member. The angle detection means detects the direction angle with respect to the longitudinal axis direction when swinging due to the tension from the wire, and there is a difference of a predetermined amount or more in the extension amount of the working device obtained from the detection value by the extension amount detection means and the angle detection means. When it occurs, it has failure determination means (for example, the failure determination circuit 33 in the embodiment) that determines that one of the extension amount detection means and the angle detection means has failed.

  According to the failure detection device for an aerial work vehicle related to the present invention, among the extension amount detectors provided in each outrigger beam, an extension amount detector attached to detect a failure of the extension amount detector, By comparing the detection value of the extension amount by multiple extension amount detectors with the detection value of the extension amount detector for detecting the failure, it is confirmed that some failure has occurred in any of these extension amount detectors. Judgment can be made. For this reason, detection that must be attached to the vehicle body compared to the conventional method (so-called double sensor) in which each extension amount detector is attached with a double extension detector for failure detection and the detected values are compared. Since the number of detectors can be reduced, a failure detection device for an extension amount detector can be provided in the vehicle body at a low cost by the number of detectors that can be reduced.

  Further, in the method of detecting a failure by a plurality of extension amount detection means provided in each outrigger beam being composed of a first extension amount detection means and a second extension amount detection means, the second extension amount detection means is inexpensive. A simple angle detector is used. Then, by such a failure detection means, it is possible to determine that one of the detectors has failed by comparing the detection values of the first extension amount detection means and the second extension amount detection means with each other. For this reason, compared with the conventional thing (what is called a dual sensor) which compares these detection values using the extension amount detection means similar to the 1st extension amount detection means as the 2nd extension amount detection means, with a simple structure, In addition, the cost of the failure detector of the extension detector can be reduced by the amount of the inexpensive second extension detector.

  A preferred embodiment of a failure detection apparatus for an aerial work vehicle according to the present invention will be described below with reference to FIGS. FIG. 1 shows an example of an aerial work vehicle equipped with the failure detection apparatus. The aerial work vehicle 1 is capable of traveling with front and rear wheels 3a and 3b on the front, rear, left and right sides of the vehicle body 2, and is constructed based on a truck vehicle having a driving cabin 2a at the front portion of the vehicle body 2. On the vehicle body 2 of the truck vehicle, there is disposed a turntable 4 that is driven by a turn motor 51 and configured to be able to turn horizontally. The base 5 is pivotally connected to the swivel 4 and a boom 5 is attached. The boom 5 is moved up and down by a hoisting cylinder 52. The boom 5 has a base boom 5a, an intermediate boom 5b, and a tip boom 5c combined in a nested manner, and a built-in telescopic cylinder 53 (hereinafter referred to as a swing motor 51, a hoisting cylinder 52, and a telescopic cylinder 53 are combined to form a “boom actuator 54”. ), The entire boom 5 is configured to be movable in the longitudinal axis direction.

  The tip boom 5c has a boom head 5d at the tip, and a vertical post member 6 is pivotably attached to the boom head 5d so as to swing up and down. The vertical post member 6 is controlled by swinging of the vertical post member 6 by a leveling cylinder (not shown) disposed between the tip of the tip boom 5c or the boom head 5d and the vertical post member 8, and the boom 5 is raised and lowered. In any case, the vertical post member 6 is controlled to swing so that the vertical post member 6 always extends vertically. The work table 7 is attached to the vertical post member 6 that is always held vertically in such a manner that it can be swiveled horizontally (swinged freely) by a swiveling motor (not shown). Retained.

  Further, the work table 7 is provided with a boom operation device 16 for performing an operation for operating the boom 5, and an operator who rides on the work table 7 operates an operation lever of the boom operation device 16. Thus, the boom 5 is freely swiveled, undulated, and expanded and contracted, and the work table 7 can be moved to an arbitrary high position.

  .. Are provided at four positions, front, rear, left and right of the vehicle body 2, that are widened outward in the left-right direction of the vehicle body 2 and retractable below the vehicle body 2. The outriggers 8 and the like include a pair of front outriggers including a left front outrigger 8 and a right front outrigger 9 (not shown) provided on the left and right of the front part of the vehicle body 2, and a left rear outrigger 8 ′ and a right provided on the left and right of the rear part of the vehicle body 2. The rear outrigger is composed of a pair of rear outriggers 9 '. When working at a high place, by operating a jack operating device 15 provided at the rear of the vehicle body 2, the outrigger 8 and the like are widened to the left and right of the vehicle body 2 and extended and extended downward to stably support the vehicle body 2. It can be done. Also, a boom receiver 17 is provided at the center of the vehicle body 2 so as to project upward and come into contact with the lower surface of the boom 5 that has fallen down in a fully contracted state to store and support the boom 5.

  The left front outrigger 8 will be described in more detail with reference to FIG. 2. The outrigger 8 includes an outrigger beam 10 that is inserted into the left end of the vehicle body 2 so as to be extendable toward the side of the vehicle body 2, and the outrigger beam. And a jack 12 attached perpendicularly to the outrigger beam 10 at the tip of 10. An outrigger cylinder 13 is attached between the vehicle body 2 and the inner tip of the outrigger beam 10, and the entire outrigger beam 10 is expanded and contracted by the expansion / contraction operation of the outrigger cylinder 13. Note that the tip of the piston rod 13a of the outrigger cylinder 13 is pin-held inside the tip of the outrigger beam 10, and the base end of the cylinder tube 13b is pin-held by the vehicle body 2 although not shown here.

  The jack 12 includes an outer post 12a attached to the front end of the outrigger beam 10 so as to extend downward from the vehicle body 2, and an inner post 12b inserted into the outer post 12a so as to be extendable downward from the outer post 12a. , And a grounding plate (lower end grounding portion) 12c attached to the lower end portion of the inner post 12b. A jack cylinder 14 is attached between the inner upper portion of the outer post 12a and the inner lower portion of the inner post 12b, and the tip of the piston rod 14a of the jack cylinder 14 is pin-held inside the lower end of the inner post 12b. The upper end of the cylinder tube 14b is pin-held inside the upper end of the outer post 12a.

  In the outrigger 8 configured as described above, when the hydraulic oil from a hydraulic pump (not shown) provided in the vehicle body 2 is supplied to the outrigger cylinder 13 and expands and contracts, the entire outrigger beam 10 expands and contracts with respect to the vehicle body 2. The outer post 12a and the like move in the projecting direction (the direction indicated by the arrow H in the drawing) and the drawing direction with respect to the vehicle body 2. On the other hand, when the hydraulic oil from the hydraulic pump is supplied to the jack cylinder 14 and is expanded and contracted, the inner post 12b expands and contracts vertically with respect to the outer post 12a. When working at a high place, the vehicle body 2 is lifted and supported by extending the inner post 12b below the vehicle body 2 with the outrigger beam 10 extending to the side of the vehicle body 2 and grounding the grounding plate 12c. .

  The four outriggers 8, 8 ′,... And the boom 5 configured as described above are provided in the hydraulic unit 40 provided corresponding to the jack 12 and the boom 5, such as the outrigger beam 10, as shown in FIG. The control valve 41, 42, 43 controls the supply and discharge of hydraulic oil discharged from a hydraulic pump (not shown) that is driven by transmitting the rotational driving force of the engine disposed in the vehicle body 2. , 8 ′,... And boom 5 undulation, turning, and telescopic motion can be controlled.

  The operation control of the control valves 41 and 42 corresponding to the outrigger beam 10 and the like and the jack 12 is performed by operating the jack operating device 15 provided at the rear portion of the vehicle body 2. When the jack operating device 15 is operated, based on the operation signal from the jack operating device 15, the operation control of the control valves 41 and 42 for controlling the supply and discharge of the hydraulic oil to the outriggers 8, 8 ',. The expansion / contraction operation to the side of the vehicle body such as 10 and the expansion / contraction operation of the jack 12 to the lower side of the vehicle body are controlled.

  When the boom operation device 16 provided on the work table 10 is operated, the control of the control valve 43 is controlled based on the operation signal from the boom operation device 16, and the boom 5 is moved up and down, swiveled, and extended and retracted. Control is performed.

First embodiment

  Here, a first embodiment using the failure detection device 60 for an aerial work vehicle according to the present invention will be described with reference to FIGS. In the aerial work vehicle 1 configured as described above, the boom moment acting on the vehicle body 2 that changes according to the operating state (the undulation angle and the extension amount) of the boom 5 and the load weight of the workbench 7 becomes excessive, Depending on the extension amount of the outrigger beam 10 or the like, the vehicle body 2 may not be stably supported by the outrigger 8 or the like. In order to prevent this, the operating range of the boom 5 in which the vehicle body 2 can be stably supported by the outriggers 8 and the like is calculated based on the extension amount of each outrigger beam 10, 10 '... It is necessary to accurately detect the amount of extension of 10, 10 '... to the side of the vehicle body 2.

  For this reason, as shown in FIG. 3, in the case of the front outriggers 8 and 8 ′, for example, in the case of the front outriggers 8 and 8 ′, the failure detection device 60 for an aerial work platform according to the present invention The extension amount detector A21 and the extension amount detector B21 ′ for detecting the extension amounts of the right front outrigger beam 10 ′ relative to the left front outrigger beam 10 can be detected. Each of the extension amount detectors 21, 21 ′, 22 including the extension amount detector C 22 attached to determine whether or not the extension amount detectors 21, 21 ′, 22 are out of order, and the controller 30 are provided. Configured.

  Here, the extension amount detectors 21, 21 ′, and 22 that detect the extension amounts of the outrigger beams 10 and 10 ′ will be described with reference to FIGS. 4 and 5. An extension amount detector A21 (illustrated as sensor A21 in FIG. 5) includes a reel 21a that is rotatably attached to the outer post 12a of the outrigger 8 and has a built-in potentiometer (wire reel type variable resistor). The wire 21b is wound around. This potentiometer detects the amount of rotation (rotation angle) of the reel 21a when the wire 21b is wound around the reel 21a according to the expansion / contraction movement of the outrigger beam 10.

  The tip of the wire 21b extending from the reel 21a toward the vehicle body 2 is fixed to the vehicle body 2 at the position of point P, and the reel 21a is configured to always have a biasing force in the direction of winding the wire 21b. Yes. For this reason, when the outrigger beam 10 extends and contracts with respect to the vehicle body 2, the reel 21a rotates while maintaining the state in which the wire 21b is pulled. Then, the amount of rotation of the reel 21a is detected by the potentiometer, so that the extension amount detector A21 detects the extension amount of the outrigger beam 10 with respect to the vehicle body 2.

  Similarly, an extension amount detector B21 ′ (illustrated as sensor B21 ′ in FIG. 5) attached to the outer post 12a of the outrigger 8 ′ is also composed of a reel 21′a and a wire 21′b. The tip of the wire 21'b extending from 'a to the vehicle body 2 side is fixed to the vehicle body 2 at the position of the point Q, and detects the extension amount of the outrigger beam 10' with respect to the vehicle body 2.

  Further, the extension amount detector C22 (illustrated as sensor C22 in FIG. 5) includes a reel 22a that is rotatably attached to the outer post 12a of the outrigger 8 'and has a built-in potentiometer, and a wire 22b wound around the reel 22a. Consists of The tip of the wire 22b extending from the reel 22a toward the vehicle body 2 is fixed to the inner wall surface of the outrigger beam 10 at the point R, and the reel 22a always has a biasing force in the direction of winding the wire 22b. Configured. For this reason, when the outrigger beam 10 and the outrigger beam 10 'both extend and retract to the side of the vehicle body 2, the reel 22a rotates while maintaining the state in which the wire 22b is pulled, and the outrigger beam 10 and the outrigger beam 10' Can be detected (the relative extension amount of the outrigger beam 10 'with respect to the outrigger beam 10).

  As shown in FIG. 5, the same applies to the extension amount detector provided on the outriggers 9, 9 ′ on the rear side of the vehicle body 2, and a sensor D 23 is attached to the outrigger 9 to determine the extension amount of the outrigger beam 11 with respect to the vehicle body 2. The sensor E23 ′ is attached to the outrigger 9 ′ to detect the extension amount of the outrigger beam 11 ′ with respect to the vehicle body 2. The sensor F24 attached to the outrigger 9 'detects the total value of the extension amounts of the outrigger beam 11 and the outrigger beam 11' (the relative extension amount of the outrigger beam 11 'with respect to the outrigger beam 11).

  Referring to FIG. 3, the failure detection device 60 operates in the controller 30 in addition to the respective expansion amount detectors 21, 21 ′, 22, an arithmetic circuit 31, a storage circuit 32, a failure determination circuit 33, And a regulation circuit 34.

  The arithmetic circuit 31 has values of the extension amounts of the outrigger beam 10 and the outrigger beam 10 ′ detected by the extension amount detector A 21 and the extension amount detector B 21 ′ when the outrigger beam 10 and the outrigger beam 10 ′ are extended. (Indicated by sensors A and B, respectively). That is, the calculation of sensor A + sensor B is performed. Further, the arithmetic circuit 31 calculates the difference between the added extension amount and the extension amount detected by the extension amount detector C22. That is, | sensor C− (sensor A + sensor B) | is calculated.

  In the storage circuit 32, in order to determine that one of the expansion amount detectors 21, 21 ′, 22 has failed, the | sensor C− (sensor A + sensor B) | A value for comparison with the value is preset and stored.

  When the value of | sensor C− (sensor A + sensor B) | calculated by the calculation circuit 31 exceeds a predetermined value stored in the storage circuit 32, the failure determination circuit 33 breaks the wire 21b or the like It is determined that one of the extension amount detectors 21, 21 ′, and 22 has failed due to a malfunction such as a winding failure such as 21 a.

  When it is determined by the failure determination circuit 33 that the extension amount detectors 21, 21 ′, 22 have failed, the operation regulating circuit 34 controls the supply and discharge of the hydraulic oil supplied to the boom actuator 54. The operation of the boom 5 is restricted by restricting the output of the operation control signal to. According to this operation restriction, the boom moment acting on the vehicle body 2 from the boom 5 increases according to the operation position of the tip of the boom 5 (workbench 7), so that the outrigger 8 and the like cannot stably support the vehicle body 2. In order to prevent this, the boom 5 is restricted from operating in the direction in which the boom 5 falls, the direction in which the boom 5 extends, or the direction in which the boom 5 turns to the side of the vehicle body 2. For this reason, even when the failure determination circuit 33 determines that the extension amount detectors 21, 21 ′, and 22 are in failure, the boom 5 is lifted in a direction in which the boom moment acting on the vehicle body 2 is not likely to increase. The operation lever of the boom operation device 16 can be operated so that the boom 5 operates in the direction in which the boom 5 contracts.

  Although the first embodiment has been described above, the present invention is not limited to the present embodiment, and an extension amount detector that detects the extension amount of each outrigger beam 10, 10 '... Is configured as follows. May be. For example, as shown in FIG. 6, sensor A21, sensor B21 ′, and sensor D23, which are extension amount detectors for detecting the extension amounts of the outrigger beams 10, 10 ′, 11, 11 ′ on the outriggers 8, 8 ′,. In addition, the sensor C23 for detecting a failure of the extension amount detector may be provided in the vehicle body 2 after attaching the sensor E23 ′.

  In this case, the wire 22c attached to the sensor C22 so as to be able to be wound and fed out extends from the sensor C22 and is attached to the outer post 12a of the outriggers 8, 9, 9 '. It is wound around d and several sheaves attached to the vehicle body 2, and its tip is fixed at the point S to the outer post 12a of the right front outrigger 8 '.

  For this reason, when a part or all of the outrigger beams 10, 10 ', 11, 11' expand and contract, the sheave 21d and the like rotate, and the wire 22c is taken up and fed out from the sensor C22. , 10 ′, 11, 11 ′ can be detected as a total value. At this time, the arithmetic circuit 31 determines the extension amounts of the outrigger beams 10, 10 ′, 11, 11 ′ detected by the sensors A21, B21 ′, D23, and E23 ′ (sensor A, sensor B, Sensor D and sensor E). That is, the calculation of sensor A + sensor B + sensor D + sensor E is performed. Further, a difference between the added extension amount and the extension amount detected by the sensor C22 (indicated by the sensor C) is calculated. That is, the calculation of | sensor C- (sensor A + sensor B + sensor D + sensor E) | is performed.

  When the failure determination circuit 33 exceeds the predetermined value stored in the storage circuit 32 when the value of | sensor C− (sensor A + sensor B + sensor D + sensor E) | It is determined that any of A21, sensor B21 ′, sensor D23, and sensor E23 ′ has failed. When it is determined that any of the sensor A, sensor B, sensor D, and sensor E has failed, the operation restriction circuit 34 supplies the control valve 43 that controls the supply and discharge of the hydraulic oil supplied to the boom actuator 54. The operation of the boom 5 is restricted by restricting the output of the operation control signal.

  This operation restriction regulates the operation of the boom 5 in the direction in which the boom 5 falls, the direction in which the boom 5 extends, or the direction in which the boom 5 turns to the side of the vehicle body 2. The operation lever of the boom operation device 16 can be operated so as to operate in the direction to face up or the direction in which the boom 5 contracts.

Second embodiment

  Here, a second embodiment using the failure detection apparatus for an aerial work vehicle according to the present invention will be described with reference to FIGS. As shown in FIG. 7, the failure detection device 60 ′ in this example is similar to the first embodiment in that the outriggers 8, 8 are based on the operation signals from the jack operation device 15 and the boom operation device 16. ′,... And a controller 30 that controls the boom 5 and a hydraulic unit 40 that controls the supply and discharge of hydraulic oil to and from the outrigger cylinder 13. In this embodiment, an extension amount detector 23 and an angle detector 26 are attached to each outrigger beam 10, 10 ',.

  Hereinafter, the extension amount detector 23 and the angle detector 26 that detect the extension amount of the left front outrigger beam 10 will be described as an example. As shown in FIG. 8, an extension amount detector 23 including a potentiometer and a rotatable reel 23 a is attached to the vehicle body 2. Further, the wire 24 extends from the reel 23a so as to be freely retracted and wound around a sheave 25 attached to the outrigger beam 10, and the tip of the wire 24 is fixed to an angle detector 26 attached to the vehicle body 2. Yes. As described above, the wire 24 between the extension amount detector 23 and the sheave 25 and the wire 24 between the angle detector 26 and the sheave 25 have a predetermined angle.

  The reel 23a always has an urging force in a direction in which the wire 24 is wound up. For this reason, when the outrigger beam 10 expands and contracts with respect to the vehicle body 2, the wire 24 is taken up and reeled out while maintaining the state where the wire 24 is pulled, and the reel 23 a rotates. The rotation amount of the reel 23a is detected by a built-in potentiometer (variable resistor), and based on this, the extension amount detector 23 can detect the extension amount of the outrigger beam 10 with respect to the vehicle body 2.

  The angle detector 26 has a built-in potentiometer and a rotatable rotating shaft 26a. A proximal end side is attached to the rotating shaft 26a, and a distal end side is fixed to the distal end of the wire 24 extending from the sheave 25 and swings about the rotating shaft 26a. It consists of a possible arm part 26b.

  When the outrigger beam 10 is expanded and contracted with respect to the vehicle body 2, the sheave 25 attached to the outrigger beam 10 moves in the longitudinal axis direction of the outrigger beam 10, and the wire 24 is wound and fed out from the reel 23a. When the outrigger beam 10 extends to the side of the vehicle body 2, the wire 24 is fed from the reel 23 a, and the arm portion 26 b of the angle detector 26 receives tension in the direction of the sheave 25 that moves from the wire 24, In the direction in which the angle θ formed by the longitudinal axis direction of the arm portion 26b and the longitudinal axis direction of the outrigger beam 10 is small (in the direction in which θ becomes a sharper angle), the arm portion 26b It swings around the rotation shaft 26a. Then, an angle θ formed between the longitudinal axis direction of the arm portion 26b and the longitudinal axis direction of the outrigger beam 10 is detected by a rotation amount (rotation angle) of the rotation shaft 26a accompanying the swinging of the arm portion 26b by a built-in potentiometer. And a detection signal is output to the controller 30.

  On the other hand, when the outrigger beam 10 is retracted toward the side of the vehicle body 2, the wire 24 is wound around the reel 23a as the sheave 25 moves toward the vehicle body 2, and the longitudinal direction of the arm portion 26b is The arm portion 26b swings about the rotation shaft 26a in a direction in which the angle θ formed with the longitudinal axis direction of the outrigger beam 10 is increased. Then, an angle θ formed between the longitudinal axis direction of the arm portion 26b and the longitudinal axis direction of the outrigger beam 10 is detected by a rotation amount (rotation angle) of the rotation shaft 26a accompanying the swinging of the arm portion 26b by a built-in potentiometer. And a detection signal is output to the controller 30.

  As will be described later, the controller 30 stores in advance an angle θ corresponding to the extension amount of the outrigger beam 10, and obtains the extension amount of the outrigger beam 10 with respect to the vehicle body 2 based on the detection signal from the angle detector 26. be able to.

  Here, the configuration and function of the extension amount detector 23 and the angle detector 26 attached to the left front outrigger 8 have been described as an example. However, the outrigger 8 ′, the outrigger 9 and the outrigger 9 ′ also have the above configuration. The extension amount detector and the angle detector are attached, and the extension amounts of the front, rear, left and right outriggers 10, 10 ',.

  Here, the operation control of the failure detection device 60 ′ configured to include the extension amount detector 23 and the angle detector 26 as described above will be described with reference to FIG. As shown in FIG. 7, in addition to the extension amount detector 23 and the angle detector 26, the failure detection device 60 ′ includes a storage circuit 32, a failure determination circuit 33, and an operation restriction circuit 34 in the controller 30. Have.

  The storage circuit 32 stores in advance an angle θ corresponding to the extension amount of the outrigger beam 10. By detecting the angle θ that changes due to the swing of the arm portion 26 b of the angle detector 26, the storage circuit 32 detects the angle θ. The extension amount with respect to the vehicle body 2 can be obtained. In addition, the storage circuit 32 stores in advance a difference between detection values of the extension amount detector 23 and the angle detector 26 for determining that one of the extension amount detector 23 and the angle detector 26 has failed. It is set and memorized.

  The failure determination circuit 33 compares the detection value detected by the extension amount detector 23 with the detection value detected by the angle detector 26. When the difference between these values becomes greater than or equal to a predetermined value preset in the storage circuit 32, the failure determination circuit 33 disconnects the wire 24 to either the extension amount detector 23 or the angle detector 26. It is determined that a failure has occurred due to a malfunction such as a winding failure of the reel 23a.

  When the failure determination circuit 33 detects a failure in either the extension amount detector 23 or the angle detector 26, the operation restriction circuit 34 operates the control valve 43 as in the case of the first embodiment. The operation of the boom 5 is restricted by restricting the output of the control signal. As in the case of the first embodiment, the operation restriction is that the boom 5 operates in the direction in which the boom 5 falls, the direction in which the boom 5 extends, or the direction in which the boom 5 turns to the side of the vehicle body 2. The control lever of the boom operation device 16 can be operated so as to operate in the direction in which the boom 5 rises or the boom 5 contracts.

  Although the second embodiment has been described above, the present invention is not limited to the detection of the extension amount of the outrigger beam as in the present embodiment. For example, in an aerial work vehicle having a boom that is constructed by combining a plurality of booms in a telescopic manner and has a boom that can be extended and contracted, as shown in FIG. An angle detector 26 having a movable arm portion 26b is attached, a rotatable sheave 25 is attached to the tip boom 5c, and one end of a wire 24 is wound around the extension amount detector 23 and wound around the sheave 25. You may comprise so that an edge may be fixed to the front-end | tip of the arm part 26b of the angle detector 26. FIG.

  According to such a configuration, when the distal end boom 5c expands and contracts with respect to the proximal end boom 5a, the wire 24 is taken up and extended from the extension amount detector 23 in accordance with the movement of the sheave 25, and the angle detector. 26 arm portion 26b swings, and swing angle θ is detected by angle detector 26. Therefore, if the swing angle θ corresponding to the extension amount of the tip boom 5c is stored in advance, the angle detection is performed by detecting the swing angle θ that changes due to the swing of the arm portion 26b of the angle detector 26. The device 26 can detect the extension amount of the distal end boom 5c with respect to the proximal end boom 5a.

  Further, a rotatable sheave is attached to the base end side member (for example, the vehicle body 2 and the base end boom 5a), and the extension amount detector and the vibration as described above are attached to the front end side member (for example, the outrigger beam 10, the front end boom 5c). An angle detector having a movable arm portion is attached, and one end of a wire connecting these detectors is wound around the extension amount detector and wound around a sheave, and the other end is fixed to the tip of the arm portion of the angle detector. You may comprise as follows.

  According to such a configuration, for example, when the distal end boom 5c expands and contracts with respect to the proximal end boom 5a, the wire is wound and fed from the extension amount detector according to the movement of the extension amount detector. The arm portion of the detector swings, and the angle detector detects the swing angle. Therefore, if the swing angle corresponding to the extension amount of the tip boom 5c is stored in advance, the angle detector detects the swing angle that changes due to the swing of the arm portion of the angle detector, so that the angle detector can detect the tip boom. The extension amount of the base end boom 5a of 5c can be detected.

It is a perspective view of an aerial work vehicle provided with a failure detection device according to the present invention. It is front sectional drawing of the outrigger arrange | positioned at the said aerial work vehicle. It is a block diagram which shows the failure detection apparatus of the aerial work vehicle which concerns on this invention. It is a front view of the outrigger for demonstrating the expansion amount detector provided in the said outrigger. It is a top view of the aerial work vehicle typically expressed in order to explain the extension amount detector. It is a top view of the aerial work vehicle typically expressed in order to explain the extension amount detector. It is a block diagram for demonstrating 2nd Embodiment of the said failure detection apparatus. It is a front view of the outrigger for demonstrating the expansion amount detector in 2nd Embodiment of the said failure detection apparatus. It is a side view of the boom for demonstrating one Example in 2nd Embodiment of the said failure detection apparatus.

Explanation of symbols

1 High-altitude work vehicle 2 Car body (base end side member)
4 swivel 5 boom (working device)
5a Base end boom (working device, base end side member)
5b Intermediate boom (working device)
5c Tip boom (working device, tip side member)
8 Outrigger (Working equipment)
8 'Outrigger (Working device)
9 Outrigger (Working equipment)
9 'Outrigger (Working device)
10 Outrigger beam (work device, tip side member)
10 'Outrigger beam (working device, tip side member)
11 Outrigger beam (working equipment, tip side member)
11 'Outrigger beam (working device, tip side member)
21 Extension amount detector A (Extension amount detection means, first extension amount detection means)
21 'extension amount detector B (extension amount detection means, first extension amount detection means)
22 Extension amount detector C (extension amount detection means, second extension amount detection means)
23 Extension amount detector (Elongation amount detection means)
24 wires (extension detection wire)
25 sheave 26 angle detector (angle detection means)
31 Arithmetic circuit (calculation means)
32 Memory circuit (memory means)
33 Failure judgment circuit (failure judgment means)
60 Failure detection device 60 'Failure detection device

Claims (3)

A failure detection device for an aerial work vehicle having a plurality of outriggers arranged to be movable in a telescopic manner toward the side of the vehicle body in front, rear, left, and right of a travelable vehicle body,
A plurality of extension amount detecting means provided on each of the outriggers for detecting an extension amount of the outrigger to the side of the vehicle body;
A first extension amount detection means for detecting an extension amount of each outrigger;
A second extension amount detecting means for detecting a total extension amount of the plurality of outriggers ,
further,
Calculating means for calculating the sum of the detection values by the first extension amount detecting means;
Storage means for presetting and storing a difference between a calculated value by the calculation means and a detection value by the second extension amount detection means for determining that any of the extension amount detection means has failed;
When the difference between the calculated value by the computing means and the detected value by the second expansion amount detection means exceeds the set value stored in the storage means, it is determined that one of the expansion amount detection means has failed. A failure detection device for an aerial work vehicle, characterized by comprising failure determination means. An aerial work vehicle having a working device in which a proximal end member and a distal end side member are nested in a vehicle body that can travel, and the distal end member is attached to the proximal end member so as to be movable in the longitudinal axis direction. A fault detection device of
  An extension amount detecting means attached to one of the base end side member and the distal end side member, and having an extension amount detecting wire that can be wound and fed out;
  A sheave attached to the other member of the base end side member and the tip end side member and wound around the extension amount detection wire fed out from the extension amount detection means;
  A distal end of the extension amount detection wire attached to one of the base end side member and the distal end side member and wound around the sheave is locked, and an extending direction angle of the extension amount detection wire is detected. And a fault detection device for an aerial work vehicle, characterized in that: When the wire is wound up and fed out from the extension amount detecting means in response to the movement of the distal end side member with respect to the proximal end side member in the longitudinal axis direction, and the angle detecting means swings due to the tension from the wire The angle detection means detects the direction angle with respect to the longitudinal axis direction of
  When a difference greater than or equal to a predetermined amount occurs in the extension amount of the working device obtained from the detection values of the extension amount detection means and the angle detection means, either the extension amount detection means or the angle detection means The failure detection device for an aerial work platform according to claim 2, further comprising failure determination means for determining that a failure has occurred.

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