JP6554861B2 - Work vehicle - Google Patents

Description

  The present invention relates to a work vehicle capable of simultaneously turning a turning body and raising and lowering a boom.

  2. Description of the Related Art Conventionally, a crane vehicle is known that includes a lower traveling body, an upper revolving body that is supported by the lower traveling body so as to be able to swivel, and a boom that is supported by the upper revolving body so as to be raised and lowered (for example, Patent Document 1). 2). Further, in the crane vehicles described in Patent Documents 1 and 2, for example, in order to prevent the crane vehicle from overturning or to prevent contact with an obstacle, a work limit region and a turning slow stop region are set. Yes.

  The work limit area is an area where entry of the tip of the boom is prohibited. The turning slow stop area is an area where the turning speed of the upper turning body is gradually reduced so that the tip of the boom does not enter the work limit area. Then, the crane vehicle gradually reduces the turning speed so that the turning of the upper turning body stops before the work limit area when the tip of the boom enters the turning slow stop area during the turning of the upper turning body ( Hereinafter referred to as “slow stop”).

JP 11-139771 A Japanese Patent No. 3252007

  However, the above-described slow stop control is based on the premise that the upper swing body is turned independently. Therefore, when the turning of the upper swing body and the collapse of the boom are performed at the same time, the swing of the upper swing body may have to be stopped suddenly. As a result, the suspended load may swing greatly or the boom may be damaged.

  The present invention has been made in view of the above circumstances, and the purpose of the present invention is to prevent the turning of the boom from being stopped suddenly even when the turning of the turning body and the collapse of the boom are performed at the same time. An object of the present invention is to provide a work vehicle capable of suppressing entry into a limit area.

(1) A work vehicle according to the present invention includes a traveling body, a revolving body supported by the traveling body so as to be able to swivel, a boom supported by the revolving body so as to be raised and lowered, and a turning actuator for turning the revolving body. And a hoisting actuator for raising and lowering the boom, a first operation unit for accepting an operation for instructing the turning of the revolving body, a second operation unit for accepting an operation for instructing an overturn of the boom, and a control unit. The control unit includes a turning process in which the turning actuator turns the turning body in response to the operation of the first operation unit, and the undulation actuator in response to the operation of the second operation unit. A lowering process for causing the boom to fall, a first determination process for determining a limit line indicating a boundary between a workable area where the tip of the boom is allowed to enter and a work limit area where entry is prohibited, and the limit line A second determination process for determining a restriction area for restricting simultaneous execution of the turning process and the overturning process to the workable area side, and the turning according to the fact that the tip position of the boom is within the restriction area. One of the actuator and the undulation actuator is not driven, and a restriction process for notifying that the tip of the boom is located in the restriction region is executed. In the first determination process, the control unit is a limit line that indicates a boundary of the work limit region where entry of the tip of the fallen boom is prohibited, and is a first fall of an arc shape having a first radius. The limit line and the second fall limit line having a second radius smaller than the first radius in the turning direction and the approach of the tip of the boom by turning the turning body are prohibited. The limit line indicating the boundary of the work limit area, the turning limit line connecting the adjacent ends of the first lodging limit line and the second lodging limit line are determined, and the second determination process The intersection of the second lodging limit line and the turning limit line is one of the vertices, an extension line of a predetermined length of the second lodging limit line is a first contour line, and a predetermined line of the turning limit line is set. Graphic area with the extended line as the second outline , It is determined that the regulating area.

  According to the above configuration, one of the turning actuator and the undulation actuator is not driven in response to the tip of the boom being located in the restriction region. As a result, it is possible to suppress the sudden stop of the turning due to the simultaneous execution of the turning of the turning body and the collapse of the boom. In addition, by notifying the operator that the tip of the boom is located within the restriction region, it is possible to prompt the operator to stop one of the first operation unit and the second operation unit. As a result, it is possible to suppress entry of the boom tip to the work limit area without suddenly stopping the turning of the turning body.

(2) More preferably, in the first determination process, the control unit extends side by side with the first lodging limit line on the workable area side from the first lodging limit line, and gently stops the boom falling. A first lodging / slow stop line indicating the boundary of the lodging / slowing stop region to be extended, and the second lodging limit line extending side by side with the second lodging limit line on the workable region side to indicate the boundary of the lodging / slowing / stopping region A second gradual slow stop line, and a slewing slow stop line that extends side by side with the slewing limit line on the workable region side from the slewing limit line and indicates a boundary of a slewing slow stop region that gently stops the turning of the slewing body; In the second determination process, the first contour line, the second contour line, a third contour line that is an extension of a predetermined length of the second overturning slow stop line, and the turning 4th, which is an extension of a predetermined length of the slow stop line The graphic region surrounded by the Guo line determines that the regulating area.

  According to the said structure, it can suppress that the front-end | tip of a boom enters the work limit area at a stretch from the control area | region located in the clearance gap between the overturning slow stop area | region and the turning slow stop area | region.

(3) As another example, the control unit, in the second determination process, has an arc-shaped third contour having a third radius centered on the first contour line, the second contour line, and the intersection. The graphic area surrounded by the line is determined as the restriction area.

(4) Preferably, the said control part stops the said raising / lowering actuator in the said control process in case the said 1st operation part and the said 2nd operation part are operated simultaneously.

  According to the above configuration, when the turning of the turning body and the falling of the boom are simultaneously performed in the restricted area, the falling of the boom is stopped. In general, since the boom fall speed is slower than the turning speed of the revolving structure, even if the boom fall is stopped suddenly in the regulation process, it is unlikely to be a big problem. In addition, you may decelerate to the speed which does not have a problem even if it stops suddenly.

(5) Preferably, the control unit disables the undulation actuator in the regulation process when only the first operation unit is operated.

(6) Preferably, the control unit disables the turning actuator in the regulation process when only the second operation unit is operated.

  According to the above configuration, when the tip of the boom enters the restricted area due to one of the turning of the turning body and the collapse of the boom, the other operation cannot be performed. The tip of the boom can be prevented from entering the work limit area.

According to the present invention, the turning actuator and does not drive the one of the lodging actuators, and by informing the operator that the distal end of the boom is located in the restricted area, turning and boom swing body in regulating region Can be automatically or spontaneously stopped simultaneously.

FIG. 1 is a schematic view of a rough terrain crane 10 according to the present embodiment. FIG. 2 is a functional block diagram of the rough terrain crane 10. FIG. 3 is a flowchart of the operation control process. FIG. 4 is a flowchart of the regulation process. FIG. 5 is a diagram illustrating examples of the limit lines 61 to 64 and the slow stop lines 66 to 69. FIG. 6 is a diagram illustrating an example of the restriction region in the present embodiment. FIG. 7 is a diagram illustrating an example of a restriction region in the modification.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings as appropriate. In addition, this embodiment is only 1 aspect of this invention, and it cannot be overemphasized that an embodiment may be changed in the range which does not change the summary of this invention.

[Rough terrain crane 10]
As shown in FIG. 1, the rough terrain crane 10 according to the present embodiment mainly includes a lower traveling body 20 and an upper swing body 30. The rough terrain crane 10 is an example of a work vehicle. However, a specific example of the work vehicle is not limited to the rough terrain crane 10, and may be, for example, an all terrain crane, a cargo crane, an aerial work vehicle, or the like.

[Lower traveling body 20]
The lower traveling body 20 has a pair of left and right front wheels 21 and a pair of left and right rear wheels 22 (only the right side is shown in FIG. 1). The front wheels 21 and the rear wheels 22 are rotated by the driving force of an engine (not shown) transmitted via a transmission (not shown). The lower traveling body 20 travels when a steering wheel, an accelerator pedal, a brake pedal, and the like installed in a cabin 34 described later are operated by an operator.

  Further, the lower traveling body 20 has a pair of left and right outriggers 23 provided on the front side of the lower traveling body 20 and a pair of left and right outriggers 24 provided on the rear side of the lower traveling body 20 (in FIG. 1, Only the right side is shown). The outriggers 23 and 24 can change state between an overhanging state in which the outriggers 23 and 24 are grounded to the ground at a position protruding in the left-right direction and a retracted state in which the outriggers 23 and 24 are stored in the lower traveling body 20 while being separated from the ground. is there.

  By setting the outriggers 23 and 24 to the extended state during the operation of the upper swing body 30, the posture of the rough terrain crane 10 is stabilized. On the other hand, the outriggers 23 and 24 are placed in a retracted state when the lower traveling body 20 travels. In addition, the rough terrain crane 10 can vary the amount of extension of the outriggers 23 and 24 on the left and right. In the example of FIG. 5, the overhang amounts of the right outriggers 23, 24 are smaller than the overhang amounts of the left outriggers 23, 24.

[Upper turning body 30]
The upper turning body 30 is supported by the lower traveling body 20 through a turning bearing (not shown) so as to be turnable. The upper turning body 30 is turned by a turning motor 31 (see FIG. 2). The turning motor 31 is an example of a turning actuator. Further, as shown in FIG. 1, the upper swing body 30 mainly includes a telescopic boom 32, a hook 33, and a cabin 34.

  The telescopic boom 32 is supported by the upper swing body 30 so as to be able to undulate and extend. The telescopic boom 32 is raised and lowered by the hoisting cylinder 35 and is extended and retracted by the telescopic cylinder 36 (see FIG. 2). The telescopic boom 32 is not limited to a box-type boom, and may be a lattice-type jib. The hoisting cylinder 35 is an example of a hoisting actuator. The hook 33 is suspended from a rope 38 that extends downward from the distal end of the telescopic boom 32. The hook 33 is raised and lowered by winding and unwinding the rope 38 by the winch 39 (see FIG. 2). Further, the cabin 34 includes an operation unit 56 (see FIG. 2) for operating the lower traveling body 20 and the upper swing body 30.

[Control unit 50]
As shown in FIG. 2, the rough terrain crane 10 includes a control unit 50. The control unit 50 controls the operation of the rough terrain crane 10. The control unit 50 may be realized by a CPU (Central Processing Unit) that executes a program stored in a memory, may be realized by a hardware circuit, or may be a combination thereof.

  As shown in FIG. 2, the control unit 50 acquires various signals output from the turning angle sensor 51, the undulation angle sensor 52, the boom length sensor 53, the suspension load sensor 54, the outrigger sensor 55, and the operation unit 56. To do. Further, the control unit 50 controls the turning motor 31, the hoisting cylinder 35, the telescopic cylinder 36, the winch 39, and the outriggers 23 and 24 based on the acquired various signals.

  The turning angle sensor 51 outputs a detection signal corresponding to the turning angle of the upper turning body 30 (for example, the angle in the clockwise direction with the forward direction of the lower traveling body 20 being 0 °). The hoisting angle sensor 52 outputs a detection signal corresponding to the hoisting angle of the telescopic boom 32 (the angle formed by the horizontal direction and the telescopic boom 32). The boom length sensor 53 outputs a detection signal corresponding to the length of the telescopic boom 32. The suspended load sensor 54 outputs a detection signal corresponding to the weight of the suspended load 40 suspended from the hook 33. The outrigger sensor 55 outputs a detection signal corresponding to the state of the outriggers 23 and 24 and the overhang amount.

  The operation unit 56 receives a user operation for operating the rough terrain crane 10. And the operation part 56 outputs the operation signal according to the received user operation. That is, the control unit 50 causes the lower traveling body 20 to travel based on the user operation received through the operation unit 56 and causes the upper swing body 30 to operate. The operation unit 56 includes a lever for operating the rough terrain crane 10, a steering, a pedal, an operation panel, and the like.

  The operation unit 56 according to the present embodiment includes a turning lever that drives the turning motor 31 and a hoisting lever that drives the hoisting cylinder 35. The user can turn the upper turning body 30 by operating the turning lever, and can raise and lower the telescopic boom 32 by operating the raising and lowering lever. The turning lever is an example of a first operation unit that receives an operation for instructing turning of the upper turning body 30. The raising / lowering lever is an example of a second operation unit that receives an operation for instructing the fall of the telescopic boom 32.

  For example, the control unit 50 specifies the turning direction according to the falling direction of the turning lever, and specifies the turning speed according to the amount of fall of the turning lever. Then, the control unit 50 drives the turning motor 31 so that the upper turning body 30 is turned at the turning speed specified in the specified turning direction. For example, the control unit 50 identifies the undulation direction (rise or fall) according to the lie direction of the undulation lever, and identifies the undulation speed according to the amount of the undulation lever. Then, the controller 50 drives the hoisting cylinder 35 so that the telescopic boom 32 is hoisted at the hoisting speed specified in the specified hoisting direction. In addition, a turning motor or a raising / lowering cylinder may be driven in accordance with the operation of each of the above-described turning, raising / lowering, and falling / lowering operation levers, and the speed may be specified by the amount of change in each angle.

  Further, the turning motor 31, the hoisting cylinder 35, the telescopic cylinder 36, and the winch 39 according to the present embodiment are hydraulic actuators. That is, the control unit 50 drives each actuator by controlling the direction and flow rate of the hydraulic oil to be supplied. However, the actuator of the present invention is not limited to a hydraulic type, and may be an electric type or the like.

[Operation of rough terrain crane 10]
Next, the operation of the rough terrain crane 10 will be described with reference to FIGS. For example, the control unit 50 starts the operation control process shown in FIG. 3 in response to the operation signal being output from at least one of the turning lever and the raising / lowering lever. Note that the user can operate only one of the turning lever and the raising / lowering lever alone (hereinafter referred to as “single operation”). Further, the user can operate both the turning lever and the raising / lowering lever at the same time (hereinafter referred to as “combination operation”).

  First, the control unit 50 executes a first determination process (S11). The first determination process is a process of determining a limit line indicating the boundary between the workable area and the work limit area and a slow stop line indicating the boundary of the slow stop area. The workable area is an area where the tip of the telescopic boom 32 is allowed to enter. The work limit area is an area where entry of the tip of the telescopic boom 32 is prohibited. The slow stop region is a region where the operation of the upper swing body 30 or the telescopic boom 32 is gently stopped. A workable area, a work limit area, a slow stop area, and a restriction area described later are virtual areas on a horizontal plane including the rough terrain crane 10.

  The limit lines include lodging limit lines 61 and 62 and turning limit lines 63 and 64, as shown in FIG. The fall limit lines 61 and 62 indicate the boundaries of the work limit area where entry of the fallen telescopic boom 32 is prohibited. The turning limit lines 63 and 64 indicate the boundaries of the work limit region where the intrusion of the telescopic boom 32 due to the turning of the upper turning body 30 is prohibited. Further, the slow stop lines include the overturning slow stop lines 66 and 67 and the turning slow stop lines 68 and 69. The fall / slow stop lines 66 and 67 indicate boundaries of a fall / slow stop region where the fall of the telescopic boom 32 is gently stopped. The turning gentle stop lines 68 and 69 indicate the boundaries of the turning slow stop region where the turning of the upper turning body 30 is slowly stopped. The limit line and the slow stop line are virtual lines on the horizontal plane including the rough terrain crane 10.

The control unit 50 determines the lodging limit lines 61 and 62 based on, for example, the overhang amounts of the outriggers 23 and 24 and the weight of the suspended load 40. The lodging limit line 61 has a circular arc shape with a radius R ₁ centering on the turning center of the upper turning body 30. The lodging limit line 62 has an arc shape with a radius R ₂ (<R ₁ ) centered on the turning center of the upper turning body 30. In addition, the lodging limit lines 61 and 62 are adjacent to each other in the turning direction of the upper turning body 30. The lodging limit line 61 is an example of the first lodging limit line, the lodging limit line 62 is an example of the second lodging limit line, the radius R ₁ is an example of the first radius, and the radius R ₂ is the second radius of the second radius. It is an example.

Then, in the example of FIG. 5, the control unit 50 arranges the lodging limit line 61 on the front, left, and rear of the rough terrain crane 10, and the right extension of the rough terrain crane 10 with a small overhang of the outriggers 23 and 24. A lodging limit line 62 is arranged in the direction. The control unit 50 includes, for example, set to a small enough radius _R 1, _{R 2} overhang of the outriggers 23 and 24 is small, setting a small radius _R 1, _{R 2} as the weight of the suspended load 40 is large.

  Next, the control unit 50 determines the turning limit lines 63 and 64 that connect the end points adjacent to each other of the lodging limit lines 61 and 62. In the example of FIG. 5, the turning limit line 63 is a part of a straight line that passes through the turning center of the upper turning body 30 and extends diagonally right forward of the rough terrain crane 10. Further, the turning limit line 64 is a part of a straight line that passes through the turning center of the upper turning body 30 and extends obliquely rearward to the right of the rough terrain crane 10.

Next, the control unit 50 determines the fall / slow stop lines 66 and 67 based on the fall speed of the telescopic boom 32, for example. The lodging slow stop lines 66 and 67 extend alongside the lodging limit lines 61 and 62 on the workable area side of the lodging limit lines 61 and 62. In the example of FIG. 5, the overturning slow stop line 66 has an arc shape with a radius R ₃ (<R ₁ ) centered on the turning center of the upper turning body 30. The overturning slow stop line 67 has an arc shape with a radius R ₄ (<R ₂ ) centered on the turning center of the upper turning body 30.

  “Two lines extending side by side” means that the distance between the two lines hardly changes depending on the location. Typically, if two lines are straight, they are “parallel” and if two lines are arcs, they are concentric arcs, but they need not be strictly parallel or concentric arcs. That is, as shown in FIG. 5, it means that the lodging limit lines 61 and 62 and the lodging slow stop lines 66 and 67 do not intersect with each other and extend in substantially the same direction. The relationship between turning limit lines 63 and 64, which will be described later, and turning slow stop lines 68 and 69 is the same.

Next, the control unit 50 determines the turning slow stop lines 68 and 69 based on, for example, the turning speed of the upper turning body 30. The turning slow stop lines 68 and 69 extend alongside the turning limit lines 63 and 64 on the workable region side of the turning limit lines 63 and 64. In the example of FIG. 5, the turning slow stop line 68 is a straight line that passes through the turning center of the upper turning body 30 and is inclined counterclockwise by the inclination angle θ ₁ from the turning limit line 63. The turning slow stop line 69 is a straight line that passes through the turning center of the upper turning body 30 and is inclined clockwise by the inclination angle θ ₂ from the turning limit line 64.

The control unit 50, as laid down speed of the telescopic boom 32 is high, to reduce the radius _R 3, _{R 4.} When the raising / lowering lever is not operated, the control unit 50 may determine the radii R ₃ and R ₄ based on the maximum falling speed of the telescopic boom 32. Similarly, the control unit 50 increases the inclination angles θ ₁ and θ ₂ as the turning speed of the upper turning body 30 increases. When the turning lever is not operated, the control unit 50 may determine the inclination angles θ ₁ and θ ₂ based on the maximum turning speed of the upper turning body 30.

  As a result, the region surrounded by the lodging limit lines 61 and 62 and the turning limit lines 63 and 64 becomes the workable region. Moreover, the area | region outside the lodging limit lines 61 and 62 and the turning limit lines 63 and 64 becomes a work limit area. Further, the area surrounded by the lodging limit line 61, the lodging slow stop line 66, and the turning limit lines 63, 64, and the extension line of the lodging limit line 62, the lodging gentle stop line 67, and the turning limit lines 63, 64 are surrounded. This area becomes the lodging and slow stop area. Further, a region surrounded by an extension line of the turning limit line 63, the turning slow stop line 68, the lodging limit line 61, and the lodging limit line 62, the turning limit line 64, the turning slow stop line 69, the lodging limit line 61, and A region surrounded by an extension line of the lodging limit line 62 is a turning slow stop region.

  According to the first determination process described above, the overturning slow stop region or the turning slow stop region is provided between the workable region and the work limit region. As a result, turning of the upper turning body 30 and falling of the telescopic boom 32 can be safely and slowly stopped. However, at the positions of intersections A and B of the lodging limit line 62 and the turning limit line 63, the turnable area and the work limit area are in contact with each other. That is, when the tip of the telescopic boom 32 passes near the intersections A and B by the combined operation, there is a possibility that the turning of the upper swing body 30 and the collapse of the telescopic boom 32 are suddenly stopped.

  Therefore, the control unit 50 executes a second determination process (S12). The second determination process is a process for determining the restriction area. The restriction area is an area for restricting simultaneous execution of the process of turning the upper-part turning body 30 and the process of causing the telescopic boom 32 to fall down. The restriction region is, for example, a region different from the overturning slow stop region and the turning slow stop region in the workable region. The restriction region according to the present embodiment is a region circumscribing the overturning slow stop region and the turning slow stop region. However, a part of the regulation region may overlap with the overturning slow stop region or the turning slow stop region.

  The restriction region in the present embodiment is a region formed around the intersection A of the lodging limit line 62 and the turning limit line 63. More specifically, as shown in FIG. 6, the restriction region in the present embodiment has an intersection A as one of the vertices, and an extension line of a predetermined length of the lodging limit line 62 as a first contour line 62 ′. In addition, it refers to a graphic area having an extension line of a predetermined length of the turning limit line 63 as a second contour line 63 ′. Similarly, a restriction region is also formed around the intersection B of the lodging limit line 62 and the turning limit line 64.

  As an example, as shown in FIG. 6A, the control unit 50 includes a first contour line 62 ′ that is an extension of a predetermined length of the lodging limit line 62 and a predetermined length of the turning limit line 63. A second contour line 63 ′ which is an extension line of the above, a third contour line 67 ′ which is an extension line of a predetermined length of the overturning gentle stop line 67, and an extension line of a predetermined length of the turning slow stop line 68. A graphic area surrounded by a certain fourth contour line 68 ′ may be determined as a restriction area.

As described above, the inclination angle theta ₁ of the turning slow stop line 68 increases with increasing turning speed, the first contour line 62 ', the turning speed becomes higher the longer faster. In other words, the size of the turning direction of the restriction region increases as the turning speed increases. Further, as described above, the radius R ₄ of the lodging slow stop line 67 becomes smaller as the lodging speed increases, so the second contour line 63 ′ becomes longer as the lodging speed increases. In other words, the size of the restriction area in the turning radius direction increases as the lodging speed increases.

As another example, as illustrated in FIG. 6B, the control unit 50 includes a first contour line 62 ′ that is an extension of a predetermined length of the lodging limit line 62 and a predetermined limit of the turning limit line 63. A graphic region surrounded by the second contour line 63 ′, which is an extension of the length, and the arc-shaped third contour line 70 having a radius R ₅ centered on the intersection A may be determined as the restriction region. . Control unit 50, as laid down speed is higher, and / or, as the rotation speed is high, may be increased radius R _5. That is, the first contour line 62 ′ and the second contour line 63 ′ of the restriction region shown in FIG. 6B become longer as the lodging speed is higher and / or as the turning speed is faster. Radius R ₅ is an example of a third radius.

  Next, the control unit 50 drives the turning motor 31 in response to the turning lever being operated alone (S13: turning) (S14). Moreover, the control part 50 drives the raising / lowering cylinder 35 according to the raising / lowering lever having been operated independently (S13: lying down) (S15). Further, the control unit 50 drives the turning motor 31 and the raising / lowering cylinder 35 in response to the combined operation of the turning lever and the raising / lowering lever (S13: turning & falling) (S16). The process of driving the turning motor 31 is an example of a turning process. The process of driving the hoisting cylinder 35 is an example of a fall process. In the present specification, the process of raising and lowering the telescopic boom 32 and the process of extending and retracting the telescopic boom 32 are omitted.

  In step S <b> 14, the control unit 50 supplies hydraulic oil having a flow rate corresponding to the fall amount of the turning lever to the turning motor 31 in a direction corresponding to the falling direction of the turning lever to turn the upper turning body 30. Further, in step S15, the control unit 50 supplies hydraulic oil having a flow rate corresponding to the tilting amount of the hoisting lever to the hoisting cylinder 35 in a direction corresponding to the tilting direction of the hoisting lever, and causes the telescopic boom 32 to fall. Further, in step S16, the control unit 50 executes the processes of steps S14 and S15.

  The control unit 50 continues the processes of steps S13 to S16 until the operation of the operation unit 56 ends (S17: No). Although illustration is omitted, the control unit 50 re-executes steps S11 and S12 in response to changes in the operation amounts of the turning lever and the hoisting lever or in response to changes in the weight of the suspended load 40. May be. On the other hand, the control unit 50 stops the swing motor 31 and the hoisting cylinder 35 in response to the fact that the operation unit 56 is not operated (S17: Yes), and ends the operation control process.

  Moreover, the control part 50 monitors the position of the front-end | tip of the telescopic boom 32 moved by step S14-S16 (S18, S19). The control unit 50 is, for example, a well-known method based on the turning angle acquired from the turning angle sensor 51, the undulation angle acquired from the undulation angle sensor 52, and the length of the telescopic boom 32 acquired from the boom length sensor 53. Thus, the position of the tip of the telescopic boom 32 can be specified. Then, the control unit 50 continues the turning of the upper swing body 30 and / or the fall of the extendable boom 32 in response to the tip of the extendable boom 32 being within the workable area (S18: Yes) (S13). To S16).

  Further, the control unit 50 gently stops the turning motor 31 in response to the tip of the telescopic boom 32 being in the turning slow stop region (S18: No & S19: turning slow stop region) (S20). The control unit 50 gradually reduces the turning speed of the upper turning body 30 so that the tip of the telescopic boom 32 stops on the turning limit lines 63 and 64. More specifically, the control unit 50 gradually reduces the amount of hydraulic oil supplied to the turning motor 31. That is, when the tip of the telescopic boom 32 is located within the turning slow stop region, the control unit 50 does not drive the turning motor 31 in response to the operation of the turning lever.

  Further, the control unit 50 gently stops the hoisting cylinder 35 in response to the tip of the telescopic boom 32 being in the overturning slow stop region (S18: No & S19: overturning slow stop region) (S21). The controller 50 gradually decelerates the lodging speed of the telescopic boom 32 so that the tip of the telescopic boom 32 stops on the lodging limit lines 61 and 62. More specifically, the control unit 50 gradually reduces the amount of hydraulic oil supplied to the undulation cylinder 35. That is, when the tip of the telescopic boom 32 is located in the overturning slow stop region, the control unit 50 does not drive the hoisting cylinder 35 according to the operation of the hoisting lever.

  In step S20, the control unit 50 sets the turning speed of the turning motor 31 in a speed pattern in which the suspended load 40 does not swing in the turning direction when the tip of the telescopic boom 32 stops on the turning limit lines 63 and 64. It is desirable to slow down. Similarly, in step S21, when the tip of the telescopic boom 32 stops on the turning limit lines 63 and 64, the control unit 50 causes the hoisting cylinder 35 to fall in a speed pattern that does not swing in the turning radius direction. It is desirable to reduce the speed. Such a speed pattern is determined by, for example, a swing cycle specified by the length from the tip of the telescopic boom 32 to the suspended load 40.

  Furthermore, the control part 50 performs a restriction | limiting process according to the front-end | tip of the telescopic boom 32 being a restriction | limiting area (S18: No & S19: regulation area | region) (S22). The restriction process is a process of restricting one of the turning of the upper turning body 30 and the falling of the telescopic boom 32 and / or notifying that the tip of the telescopic boom 32 is located in the restriction region. The details of the restriction process will be described with reference to FIG.

  First, the control unit 50 performs notification processing (S31). The notification process is a process of notifying the operator that the tip of the telescopic boom 32 is located within the restriction region. In other words, the notification process is a process of notifying the operator that the turning of the upper swing body 30 and the collapse of the telescopic boom 32 should not be performed simultaneously. Although the specific method of notification is not particularly limited, for example, a message may be displayed on the display (not shown) of the overload prevention device, or a warning sound may be output from a speaker (not shown), An LED (not shown) or the like may be turned on.

  Next, the control unit 50 disables the hoisting cylinder 35 in response to the single operation of the swing lever (S32: swing) (S33). The control unit 50 opens, for example, an inclining proportional pressure reducing valve disposed in an oil passage from a hydraulic oil tank (not shown) to the undulation cylinder 35. Thereby, even if the raising / lowering lever is operated in a state where the tip of the telescopic boom 32 is located in the restriction region, the raising / lowering cylinder 35 is not driven. On the other hand, the control unit 50 continues to drive the turning motor 31 according to the operation signal from the turning lever.

  Further, the control unit 50 disables the turning motor 31 in response to the fact that the fall lever is operated alone (S32: fall) (S34). For example, the control unit 50 opens a swing proportional pressure reducing valve disposed in an oil path from the hydraulic oil tank to the swing motor 31. Thereby, even if the turning lever is operated in a state where the tip of the telescopic boom 32 is located within the restriction region, the turning motor 31 is not driven. On the other hand, the control unit 50 continues to drive the hoisting cylinder 35 according to the operation signal from the hoisting lever.

  Furthermore, the control unit 50 stops the hoisting cylinder 35 in response to the swiveling lever and the hoisting lever being operated together (S32: swiveling & tilting) (S35). The control unit 50 opens, for example, an overriding proportional pressure reducing valve arranged in an oil path from the hydraulic oil tank to the turning motor 31. Thereby, the fall of the telescopic boom 32 stops, and even if an operator operates the raising / lowering lever, the turning motor 31 is not driven. On the other hand, the control unit 50 continues to drive the turning motor 31 according to the operation signal from the turning lever.

[Operational effects of this embodiment]
According to the above-described embodiment, one of the turning motor 31 and the hoisting cylinder 35 is not driven in response to the distal end of the telescopic boom 32 being located in the restriction region. As a result, the sudden stop of the turning due to the simultaneous execution of the turning of the upper turning body 30 and the overturning of the telescopic boom 32 can be suppressed. Further, by notifying the operator that the tip of the telescopic boom 32 is located within the restriction region, it is urged to stop the operation of one of the turning lever and the falling lever, or one of the turning motor 31 and the raising / lowering cylinder 35. It is possible to make the operator recognize the stoppage.

  In the regulation process, when one of the swing motor 31 and the hoisting cylinder 35 is not driven, the operating hoisting cylinder 35 is disabled (S33), and the stopped swing motor 31 is disabled ( S34), and stopping the undulating cylinder 35 being driven (S35). As a result, it is possible to prevent the tip of the telescopic boom 32 from entering the work limit area without suddenly stopping the turning of the upper turning body 30.

  Note that the method for determining the limit line, the slow stop line, and the restriction region is not limited to the above example. For example, the restriction region may be a portion surrounded by the first contour line 62 ′ and the second contour line 63 ′ in a rectangular shape having the intersections A and B as the center of gravity or the center. Further, the control unit 50 may accept an input of a limit line from the operator through the operation unit 56. In this case, the control unit 50 can determine limit lines 71 and 72 having an arbitrary shape at an arbitrary position as shown in FIG. 7, for example. Moreover, the control part 50 should just determine a control area | region to the workable area side from the limit lines 71 and 72, as FIG. 7 shows. Moreover, the determination of the slow stop line is not essential and can be omitted.

  A limit line 71 shown in FIG. 7A extends linearly to the right of the rough terrain crane 10. In this case, for example, the control unit 50 sets a restriction line 73 parallel to the limit line 71 closer to the workable area than the limit line 71 and determines an area surrounded by the limit line 71 and the restriction line 73 as the restriction area. May be. A limit line 72 shown in FIG. 7B extends in an arc shape in front of the rough terrain crane 10. In this case, the control unit 50 sets, for example, an arc-shaped restriction line 74 that is concentric with the limit line 72 and has a small radius, and determines an area surrounded by the limit line 72 and the restriction line 74 as a restriction area. Also good.

  Further, when the left and right overhang amounts of the outriggers 23 and 24 are the same, the boundaries of the lodging limit lines 61 and 62 are different from the example of FIG. The control unit 50 in this case is, for example, a region sandwiched between straight lines extending from the turning center of the upper turning body 30 to the front outrigger 23 and a straight line extending from the turning center of the upper turning body 30 to the rear outrigger 24. A first lodging limit line is set to the sandwiched area. In addition, the control unit 50 is sandwiched by a straight line extending from the turning center of the upper turning body 30 to the right outriggers 23 and 24 and a straight line extending from the turning center of the upper turning body 30 to the left outriggers 23 and 24. The second lodging limit line is set to the specified area. Further, the control unit 50 sets a portion sandwiched between the lodging limit lines 61 and 62 among the straight lines extending from the upper swing body 30 to the outriggers 23 and 24 as a turning limit line.

DESCRIPTION OF SYMBOLS 10 ... Rough terrain crane 20 ... Lower traveling body 30 ... Upper turning body 31 ... Turning motor 32 ... Telescopic boom 36 ... Hoisting cylinder 37 ... Telescopic cylinder 38 ... Rope 50: Control unit 57: Operation unit

Claims (6)

A traveling body,
A revolving structure supported to be capable of revolving on the traveling body;
A boom supported by the swivel body in a undulating manner;
A turning actuator for turning the turning body;
A hoisting actuator for hoisting the boom,
A first operation unit that receives an operation for instructing the turning of the revolving structure;
A second operation unit for receiving an operation for instructing the boom to fall down;
A work vehicle comprising a control unit,
The control unit
A turning process for turning the turning body by the turning actuator in response to the operation of the first operation unit;
In accordance with the operation of the second operation unit, a lying process for causing the hoisting actuator to fall the boom,
A first determination process for determining a limit line indicating a boundary between a workable area where entry of the tip of the boom is allowed and a work limit area where entry is prohibited;
A second determination process for determining a restriction area for restricting simultaneous execution of the turning process and the lodging process from the limit line to the workable area side;
Regulating the tip position of the boom in response to a said regulatory region, it does not drive the one of the turning actuator and the relief actuator, and the tip of the boom to notify that it is located in the regulating area processing and, to run,
In the first determination process,
The limit line indicating the boundary of the work limit area where entry of the tip of the boom that has fallen is prohibited is the first fall limit line having an arc shape with a first radius, and the first fall limit in the turning direction. A second lodging limit line adjacent to the line and having a second radius smaller than the first radius;
The limit line indicating the boundary of the work limit area where entry of the tip of the boom due to turning of the swing body is prohibited, and the adjacent end portions of the first and second fall limit lines Determine the turning limit line that connects them,
In the second determination process, an intersection of the second lodging limit line and the turning limit line is set as one vertex, an extension line of a predetermined length of the second lodging limit line is set as a first contour line, and the turning A work vehicle that determines, as the restriction region, a graphic region having an extension line of a predetermined length of a limit line as a second contour line . The control unit
In the first determination process,
A first fall / slow stop line extending from the first fall limit line alongside the first fall limit line on the workable region side and indicating a boundary of a fall / slow stop region for gently stopping the fall of the boom;
A second lodging slow stop line extending along the second lodging limit line on the workable area side from the second lodging limit line and indicating a boundary of the lodging slow stop area;
A turning slow stop line that extends alongside the turning limit line on the workable region side from the turning limit line and that indicates a boundary of a turning slow stop region that gently stops the turning of the turning body;
In the second determination process, the first contour line, the second contour line, a third contour line that is an extension of a predetermined length of the second lodging slow stop line, and the turning slow stop line The work vehicle according to claim 1 , wherein the graphic area surrounded by a fourth contour line that is an extension line of a predetermined length is determined as the restriction area. In the second determination process, the control unit includes the graphic surrounded by the first contour line, the second contour line, and a third contour line having an arc shape with a third radius centered on the intersection. The work vehicle according to claim 1 , wherein an area is determined as the restriction area. The work vehicle according to any one of claims 1 to 3, wherein the control unit stops the hoisting actuator in the restriction process when the first operation unit and the second operation unit are operated simultaneously. The work vehicle according to any one of claims 1 to 4, wherein the control unit disables the hoisting actuator in the regulation process when only the first operation unit is operated. The work vehicle according to any one of claims 1 to 5, wherein the control unit disables the turning actuator in the regulation process when only the second operation unit is operated.

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