JP2019167820A - Work vehicle - Google Patents

Abstract

To provide a work vehicle that enables an operator to easily get into an operator cab from a lifting and lowering device.SOLUTION: An operator cab 30, which is positioned on a lifting and lowering device 20, has a door 10. A detection part SE1 recognizes an operator. A door driving part 11 automatically opens the door 10 on the basis of detection of the operator by the detection part SE1.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a work vehicle, and more particularly, to a work vehicle having a lifting device.

  A wheel loader having a lifting device is disclosed in, for example, Japanese Patent Application Laid-Open No. 2008-8183 (see Patent Document 1). In the wheel loader described in this publication, a cab (cab) having a door is disposed on the lifting device.

JP 2008-8183 A

  In the wheel loader described in the above publication, the operator can easily climb the lifting device by climbing the lifting device while grasping the handrail. However, it is difficult for an operator holding a handrail to open a large door of the cab on the lifting device. Therefore, there is a problem that it is difficult for the operator to get into the cab from the lifting device.

  The present invention has been made in view of the above problems. An object of the present invention is to provide a work vehicle in which an operator can easily get into a cab from a lifting device.

  The work vehicle of this invention is equipped with the raising / lowering apparatus, the driver's cab, the detection part, and the door drive part. The cab is located on the lifting device and has a door. The detection unit recognizes the operator. A door drive part opens a door automatically based on the detection of the operator by a detection part.

  In the work vehicle described above, the cab has a step located directly below the door. In plan view, the entire door opening / closing locus overlaps with the step.

In the work vehicle described above, the door is a foldable door.
The work vehicle further includes a storage unit and a control unit. The storage unit stores operator information in advance. The control unit controls the door driving unit based on a result of collating the detection information of the operator detected by the detection unit with the operator information stored in the storage unit.

In the work vehicle, the detection unit detects that the operator has been placed on the lifting device.
In the work vehicle described above, the door is automatically closed after the operator leaves the cab.

  The work vehicle further includes a solar panel arranged on the upper surface of the cab.

  According to the present invention, since the door driving unit automatically opens the door based on the detection of the operator by the detection unit, it is easy for the operator to get into the cab from the lifting device.

It is a perspective view showing roughly the composition of the wheel loader in one embodiment of the present invention. It is a schematic plan view which shows the opening / closing operation | movement of the door used for the wheel loader in one embodiment of this invention. It is a schematic perspective view which shows the expansion | deployment / storage operation | movement of the raising / lowering apparatus used for the wheel loader in one embodiment of this invention from the left front side. It is a schematic perspective view which shows the expansion | deployment / storing operation of the raising / lowering apparatus shown in FIG. It is a functional block diagram for demonstrating operation | movement of the raising / lowering apparatus and door in the wheel loader in one embodiment of this invention. It is a 1st flowchart which shows the door opening / closing operation | movement at the time of an operator's boarding, and the storing / deployment operation | movement of a raising / lowering apparatus. It is a 2nd flowchart which shows the door opening-and-closing operation | movement at the time of an operator's boarding, and the storing and unfolding operation | movement of a raising / lowering apparatus. It is a 3rd flowchart which shows the door opening / closing operation | movement at the time of an operator's boarding, and the storing / deployment operation | movement of a raising / lowering apparatus. It is a 1st flowchart which shows the door opening / closing operation | movement at the time of an operator's alighting, and the storing / deploying operation | movement of a raising / lowering apparatus. It is a 2nd flowchart which shows the door opening / closing operation | movement at the time of an operator's alighting, and the storing / deployment operation | movement of a raising / lowering apparatus. It is a schematic plan view which shows the opening / closing operation | movement of the modification of the door used for the wheel loader in one embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, a configuration of a wheel loader as an example of a work vehicle according to an embodiment of the present invention will be described with reference to FIG. 1. The present invention is applied to a work vehicle including a cab having a door opening / closing mechanism such as a hydraulic excavator or a bulldozer. Is possible.

  In this example, the positional relationship of each part will be described with reference to an operator seated in the driver's seat in the cab 30. The front-rear direction refers to the front-rear direction of the operator seated on the driver's seat. The left-right direction (width direction) refers to the left-right direction of the operator seated on the driver's seat. The vertical direction means the vertical direction of the operator seated on the driver's seat.

  The direction facing the operator seated in the driver's seat is the front direction, and the direction facing the front direction is the rear direction. When the operator seated on the driver's seat faces the front, the right side and the left side are the right direction and the left direction, respectively. The feet of the operator seated in the driver's seat are the lower side and the upper head is the upper side.

  FIG. 1 is a perspective view schematically showing a configuration of a wheel loader according to an embodiment of the present invention. As shown in FIG. 1, the wheel loader 40 of the present embodiment mainly includes a front frame 31, a rear vehicle body 32, a work implement 33, and an elevating device (access system) 20. A front wheel 34 a is attached to each of both sides of the front frame 31. A rear wheel 34 b is attached to each of both sides of the rear vehicle body 32.

  The front frame 31 and the rear vehicle body 32 are attached to a left and right swingable by a center pin (not shown). The front frame 31 and the rear vehicle body 32 constitute an articulate structure.

  Specifically, the front frame 31 and the rear vehicle body 32 are connected by a pair of left and right steering cylinders (not shown). When the left and right steering cylinders expand and contract, the front frame 31 and the rear vehicle body 32 swing left and right about the center pin and steer. The front frame 31 and the rear vehicle body 32 constitute a vehicle body of the wheel loader 40.

  A work machine 33 is attached in front of the front frame 31. The work implement 33 includes a pair of booms 33a, a bucket 33b, a pair of boom cylinders (not shown), a bell crank 33d, a bucket cylinder 33e, and a link 33f.

  The base end portion of the boom 33 a is attached to the front frame 31 so that the boom 33 a can swing with respect to the front frame 31. The bucket 33b is swingably attached to the tip of the boom 33a. The boom cylinder connects the front frame 31 and the boom 33a. The boom 33a swings with respect to the front frame 31 as the boom cylinder expands and contracts.

  The substantially central portion of the bell crank 33d is supported by the boom 33a so that the bell crank 33d can swing with respect to the boom 33a. The bucket cylinder 33e connects the base end portion of the bell crank 33d and the front frame 31. The link 33f connects the tip of the bell crank 33d and the bucket 33b. As the bucket cylinder 33e expands and contracts, the bucket 33b swings with respect to the boom 33a.

  An engine chamber 32 b is disposed behind the rear vehicle body 32. A hydraulic oil tank 32a is disposed in front of the engine chamber 32b. The rear vehicle body 32 has a cab (for example, a cab) 30 in front of the hydraulic oil tank 32a. The cab 30 constitutes a space for an operator to enter and operate the wheel loader 40.

  The cab 30 is provided with a door opening 30a. The door opening 30a connects the internal space of the cab 30 to the external space. The cab 30 has a door 10. The door 10 is configured to be able to open and close the door opening 30a.

  A solar panel 35 is disposed in the upper part of the cab 30. The solar panel 35 generates sunlight by directly converting sunlight into electric power using a solar cell. A step 30b is attached to the side of the cab 30 and below the door opening 30a.

  Next, the structure of the door 10 in the wheel loader 40 of this Embodiment is demonstrated using FIG.

  FIG. 2 is a schematic plan view showing an opening / closing operation of a door used in the wheel loader according to the embodiment of the present invention. As shown in FIG. 2, the door 10 is, for example, a foldable (accordion) door.

  The door 10 has a plurality of (for example, two) door panels 10a and 10b. Each of the door panels 10a and 10b has substantially the same dimension in the front-rear direction as the dimension obtained by dividing the dimension in the front-rear direction of the door opening 30a into a plurality (for example, two). Each of the door panels 10a and 10b has a vertical dimension substantially the same as the vertical dimension of the door opening 30a.

  The door panel 10a is disposed behind the door panel 10b. The rear end portion of the door panel 10a is supported so as to be rotatable about the rotating shaft 10d with respect to the cab 30. As a result, the door panel 10a is centered on the rotating shaft 10d, and the door opening 30a is closed as indicated by the solid line, and the front end of the door panel 10a protrudes toward the outside space of the cab 30 as indicated by the broken line. It can be rotated between positions.

  The front end portion of the door panel 10a and the rear end portion of the door panel 10b are connected via a rotating shaft 10c. The door panel 10a and the door panel 10b are relatively rotatable around the rotation shaft 10c. As a result, the door panels 10a and 10b can rotate with each other between a state where the door panels 10a and 10b are linearly arranged in the front-rear direction as indicated by solid lines and a state where the door panels 10b and 10b are bent as indicated by broken lines.

  For example, a slide piece 10e is attached to the front end portion of the door panel 10b. The slide piece 10e is engaged with the guide rail 30aa so as to be slidable along the guide rail 30aa. The guide rail 30aa is provided in the vicinity of the door opening 30a of the cab 30. The door panel 10b is supported in the cab 30 so as to be rotatable about the slide piece 10e. As a result, the door panel 10b has a position where the door opening 30a is closed as indicated by a solid line, the door panel 10b moves rearward as indicated by a broken line, and the rear end of the door panel 10b is an external space of the cab 30. It is possible to move between the positions protruding to the side.

  As described above, the door 10 is movable between a state in which the door opening 30a is closed as indicated by a solid line and a state in which the door opening 30a is open as indicated by a broken line. The door 10 forms a folded shape by folding the door panel 10a and the door panel 10b in a state where the door opening 30a is opened.

  The door 10 can be opened and closed automatically. In order to automatically open and close the door 10, a door driving unit 11 is connected to the door 10. One end of the door drive unit 11 is attached to the cab 30 so as to be rotatable about the rotation shaft 11a. The other end of the door drive unit 11 is attached to the door panel 10b so as to be rotatable about the rotation shaft 11b. The rotating shaft 11b is a front end portion of the door panel 10b and is disposed in the vicinity of the slide piece 10e in plan view. The rotating shaft 11b is disposed offset from the door panel 10b toward the inside of the cab. Specifically, the door panel 10b has a bent portion 10b1 bent so as to extend toward the inside of the driver's cab with the door 10 closed, and the rotating shaft 11b is disposed in the bent portion 10b1. The rotating shaft 11b may be configured integrally with the slide piece 10e.

  By driving the door driving unit 11 (for example, by extending and contracting the electric actuator), the door 10 can be opened and closed. For example, when the electric actuator which is the door drive unit 11 is extended, the door 10 closes the door opening 30a, and when the electric actuator is contracted, the door 10 opens the door opening 30a. Conversely, the door 10 opens the door opening 30a when the electric actuator serving as the door driving unit 11 extends, and the door 10 and the door driving unit close the door opening 30a when the electric actuator contracts. 11 may be configured. A hydraulic cylinder may be used instead of the electric actuator.

  The wheel loader 40 according to the present embodiment further includes a control unit CR, a detection unit SE1, and a storage unit MR. The control unit CR is connected to the door drive unit 11. The controller CR is for controlling the operation of the door drive unit 11. The control unit CR includes, for example, a drive control unit, and the drive control unit drives and controls the electric actuator that is the door drive unit 11. When a hydraulic cylinder is used instead of the electric actuator, the controller CR includes, for example, a hydraulic pump and a control valve, and the hydraulic cylinder is driven and controlled by the operation of the hydraulic pump and the control valve.

  The detection unit SE1 is connected to the control unit CR. The detector SE1 is for detecting an operator. Based on the detection of the operator by the detection unit SE1, the control unit CR controls the operation of the door drive unit 11.

  By the operation of the door driving unit 11, the door 10 automatically operates to open the door opening 30a. Further, by the operation of the door drive unit 11, the door 10 automatically operates to close the door opening 30a. The detection unit SE1 may be, for example, each of a camera, a microphone, a contact sensor, a load sensor, and a smart key receiver, or any combination thereof.

  The camera as the detection unit SE1 is attached to the upper part of the cab 30, for example. The contact sensor is attached to, for example, the handrail portion 22 of the lifting device 20. Thus, the contact sensor can detect the operator when the operator who wants to get on touches the handrail portion 22 of the lifting device 20. The load sensor is attached to the lifting device 20, for example. Thus, the load sensor can detect the operator by placing the operator on the lifting device 20. A smart key receiver is paired with a smart key.

  The smart key is a portable wireless key, which allows the work vehicle and the smart key to have a short-range wireless function, and locks and unlocks the door 10 by wireless communication between the work vehicle and the smart key. is there. The smart key receiver detects the smart key carried by the operator, so that the operator can be detected.

  The detection unit SE <b> 1 may detect an operator before being placed on the lifting device 20, or may detect an operator after being placed on the lifting device 20.

  The storage unit MR is connected to the control unit CR. The storage unit MR stores operator information in advance. The control unit CR may control the door driving unit 11 based on the result of collating the operator detection information detected by the detection unit SE1 with the operator information stored in the storage unit MR. Thereby, the individual authentication of the operator who is going to get into the wheel loader 40 can be performed.

  When the detection unit SE1 is, for example, a camera, the control unit CR collates an operator image captured by the camera with operator information (image) stored in the storage unit MR. As a result of the collation, when it is determined that the operator to get on is an operator registered in advance, the door driving unit 11 may be driven to open the door 10.

  When the detection unit SE1 is, for example, a microphone, the control unit CR collates the operator's voice print collected by the microphone with operator information (voice print) stored in the storage unit MR. As a result of the collation, when it is determined that the operator to get on is an operator registered in advance, the door driving unit 11 may be driven to open the door 10.

  Further, when the detection unit SE1 is, for example, a contact sensor, the control unit CR collates operator characteristics obtained by the sensor with operator information stored in the storage unit MR. As a result of the collation, when it is determined that the operator to get on is an operator registered in advance, the door driving unit 11 may be driven to open the door 10.

  When the detection unit SE1 is, for example, a smart key receiver, the control unit CR uses the operator information (operator detection information) received by the smart key receiver to store the operator information (operator detection information) stored in the storage unit MR. Smart key information). As a result of the collation, when it is determined that the smart key matches the information of the smart key registered in advance, the door driving unit 11 may be driven to open the door 10.

  Next, the structure of the raising / lowering device 20 in the wheel loader 40 of this Embodiment is demonstrated using FIG. 3 and FIG.

  FIG. 3 and FIG. 4 are schematic perspective views of the unfolding and retracting operations of the lifting device used in the wheel loader according to the embodiment of the present invention, as viewed from the left front side and the right front side. 3 and 4, one of the left and right handrail portions 22, the left and right pair of side members 21 d and the left and right pair of rotating members 21 g, one handrail portion 22, the side member 21 d and Only the rotating member 21g is shown, and the illustration of the other handrail portion, the side member 21d, and the rotating member 21g is omitted. In FIGS. 3 and 4, the unfolded posture is indicated by a solid line, and the retracted posture is indicated by a broken line. The left-right direction of the lifting device body 21 included in the lifting device 20 corresponds to the front-rear direction of the wheel loader 40 described above.

  As shown in FIGS. 3 and 4, the lifting device 20 mainly includes a lifting device body 21, a pair of left and right handrails (handrails) 22, and a support member 23.

  The lifting device main body 21 has a pair of left and right first ends 21A and a pair of left and right second ends 21B. The lifting device main body 21 is attached to the vehicle body at the first end 21 </ b> A so that the wheel loader 40 can be rotationally driven with respect to the vehicle body.

  3 and 4, only one side member 21d of the pair of left and right side members 21d is shown as described above. Therefore, in FIG. 3 and FIG. 4, only the first end 21A on one side of the pair of left and right first ends 21A is only one side of the pair of left and right second ends 21B. Only the second end 21B is shown.

  The elevating device main body 21 can take a retracted posture and a deployed posture (use posture) by the rotational drive described above. In the retracted posture, the lifting device main body 21 stands so that the first end 21A is located on the upper side and the second end 21B is located on the lower side. In the unfolded posture, the lifting device main body 21 is inclined such that the second end portion 21B is located on the outer side of the vehicle body with respect to the first end portion 21A.

  The lifting device main body 21 mainly includes a plurality of step portions 21a, a pair of left and right side members 21d, a connecting member 21e, an auxiliary link member 21f, and a rotating member 21g. Each of the plurality of step portions 21 a is a portion that serves as a scaffold when the operator raises and lowers the lifting device body 21. The plurality of step portions 21a are arranged side by side.

  Of the plurality of steps, the uppermost step portion 21a4 located closest to the first end portion 21A is connected to the vehicle body via a pair of left and right rotating members 21g. The rotating member 21g is connected to the uppermost step portion 21a4 so as to be rotatable about the rotating shaft 21ga. The rotation member 21g is connected to the vehicle body so as to be rotatable about the rotation shaft 21gb.

  The pair of left and right side members 21d is connected to each of the plurality of step portions 21a. The pair of left and right side members 21d sandwich a plurality of step portions 21a. A ladder is constituted by the plurality of step portions 21a and the pair of left and right side members 21d.

  Each of the pair of left and right side members 21d includes a first member 21b and a second member 21c. The first member 21b extends linearly. The upper end of the first member 21b is attached to the step 30b of the cab 30 so as to be rotatable about the rotation shaft 21ba.

  The second member 21c has a straight tube portion 21ca and a protruding portion 21cc. The pipe portion 21ca is made of a pipe having an inner diameter larger than the outer diameter of the first member 21b. A part of the lower end of the first member 21b is inserted into the tube portion 21ca.

  With the first member 21b inserted into the tube portion 21ca of the second member 21c, the second member 21c can be slid relative to the first member 21b. By this sliding, it is possible to change the entire length of the first member 21b and the second member 21c (the length of the side member 21d). The side member 21d is relatively long when the lifting device body 21 is in the deployed position, and is relatively short when the lifting device body 21 is in the retracted position.

  The plurality of step units 21a include a first step unit 21a1, a second step unit 21a2, and a third step unit 21a3. The first step portion 21a1 is a step portion that is disposed on the second end portion 21B side of the first member 21b among the plurality of step portions 21a, and is rotatably attached to the first member 21b. The second step portion 21a2 is a step portion that is disposed on the second end portion 21B side of the second member 21c among the plurality of step portions 21a, and is rotatably attached to the second member 21c. The third step portion 21a3 is slidably and rotatably attached to the second member 21c between the first step portion 21a1 and the second step portion 21a2. In the present embodiment, two third step portions 21a3 are arranged between the first step portion 21a1 and the second step portion 21a2.

  The step portion 21a connected to the first member 21b other than the first step portion 21a1 is rotatably connected to the first member 21b.

  The third step portion 21a3 is connected to at least one of the first step portion 21a1 and the second step portion 21a2 by an auxiliary link member 21f. In the present embodiment, one of the two third step portions 21a3 is connected by the first step portion 21a1 and the auxiliary link member 21f. The other of the two third step portions 21a3 is connected to the second step portion 21a2 by an auxiliary link member 21f. The two third step portions 21a3 are also connected to each other by the auxiliary link member 21f.

  The auxiliary link member 21f has a so-called rhombus link mechanism. The rhombus link mechanism has a structure assembled in a rhombus shape so that the four link pieces can rotate with respect to each other. The auxiliary link member 21f extends linearly when the lifting device main body 21 is in the deployed posture, and is shrunk in a rhombus shape when the lifting device main body 21 is in the retracted posture. Therefore, the first, second, and third step portions 21a1, 21a2, and 21a3 are located away from each other when the lifting device body 21 is in the deployed posture, and approach each other when the lifting device body 21 is in the retracted position. Is located.

  An opening 21cb is formed in the tube portion 21ca of the second member 21c along the longitudinal direction thereof. The protruding portion 21cc is connected to the tube portion 21ca on the first end portion 21A side of the opening 21cb. The protruding portion 21cc protrudes to the side of the tube portion 21ca. The connection member 21e is rotatably supported at one end by a protruding portion 21cc (second member 21c). For this reason, the one end part connected to the protrusion part 21cc of the connection member 21e can slide relatively with respect to the 1st member 21b.

  The pair of left and right handrail portions 22 are attached to the side member 21 d of the lifting device main body 21. Each of the pair of left and right handrail portions 22 includes a grip portion 22a, a pair of link members 22e1 and 22e2, and a connecting piece 22b.

  The grip portion 22a is a portion that is gripped when the operator lifts the lifting device main body 21 up and down. The pair of link members 22 e 1 and 22 e 2 support the grip portion 22 a on the lifting device main body 21. The grip portion 22a is supported by the side member 21d by a pair of link members 22e1 and 22e2 so as to be parallel to the side member 21d.

  Each of the pair of link members 22e1 and 22e2 includes a first link piece 22c and a second link piece 22d. The first link piece 22c of each of the pair of link members 22e1 and 22e2 is rotatably attached to the lifting device body 21.

  Specifically, the first link piece 22c of one link member 22e1 is rotatably attached to the first member 21b. The first link piece 22c of the other link member 22e2 is also rotatably attached to the first member 21b. The first link piece 22c of the other link member 22e2 is attached to the first member 21b so as to be slidable with respect to the second member 21c along the opening 21cb of the second member 21c.

  Each of the second link pieces 22d of the pair of link members 22e1 and 22e2 is rotatably attached to each of the first link piece 22c and the grip portion 22a.

  The connecting piece 22b has one end 22b1 and the other end 22b2. One end 22b1 of the connecting piece 22b is connected to the first connecting portion of the first link piece 22c and the second link piece 22d in the one link member 22e1. The connecting piece 22b is rotatable with respect to both the first link piece 22c and the second link piece 22d in one link member 22e1.

  The other end 22b2 of the connecting piece 22b is connected to the second connection portion of the first link piece 22c and the second link piece 22d in the other link member 22e2. The connecting piece 22b is rotatable with respect to both the first link piece 22c and the second link piece 22d in the other link member 22e2.

  The first rectangular link mechanism is constituted by the first member 21b of the side member 21d, the connecting piece 22b, the first link piece 22c of the one link member 22e1, and the first link piece 22c of the other link member 22e2. It is configured. The second rectangular link mechanism is configured by the gripping portion 22a, the connecting piece 22b, the second link piece 22d of the one link member 22e1, and the second link piece 22d of the other link member 22e2.

  One end of the connection member 21e is rotatably supported by the protruding portion 21cc of the second member 21c. The other end portion of the connection member 21e is rotatably attached to the grip portion 22a together with the second link piece 22d in the other link member 22e2.

  The other end portion of the connection member 21e is connected to a connection portion between the grip portion 22a and the second link piece 22d in the other link member 22e2. Further, the central portion of the connection member 21e is connected to a connection portion of three members of the first link piece 22c and the second link piece 22d in the connection piece 22b and the other link member 22e2. Thereby, the connection member 21e is rotatable with respect to each of the first link piece 22c in the grip portion 22a, the connecting piece 22b, and the other link member 22e2.

  The handrail portion 22 operates in conjunction with the rotation operation of the lifting device main body 21. The handrail portion 22 is in a rising state when the lifting device body 21 is in the deployed position, and is in a folded state when the lifting device body 21 is in the retracted position.

  In the rising state, the grip portion 22a is located at a first position away from the lifting device main body 21. Further, in the folded state, the grip portion 22a is located at a second position closer to the lifting device body 21 than in the raised state.

  The lifting device main body 21 can be moved between the retracted posture and the deployed posture by the support member 23. The support member 23 has one end 23A and the other end 23B. One end 23A of the support member 23 is attached to the vehicle body. The other end 23B of the support member 23 is rotatably attached to the second member 21c. The distance between the one end 23A and the other end 23B of the support member 23 can be expanded and contracted.

  The support member 23 includes a connection member 23a, a drive member 23b, and a fixture 23c. The connection member 23a is rotatably attached to the second member 21c. The fixing tool 23c is attached to the vehicle body. The drive member 23b can be expanded and contracted, and is made of, for example, an electric actuator. The driving member 23b may be a hydraulic cylinder instead of the electric actuator. By extending and contracting the drive member 23b, the distance between the one end 23A and the other end 23B of the support member 23 can be expanded and contracted. Thereby, the lifting / lowering device main body 21 can be moved between the retracted posture and the deployed posture.

  As shown in FIG. 4, a control unit CR is connected to the drive member 23b. The controller CR is for controlling the operation of the drive member 23b. The control unit CR includes, for example, a drive control unit, and the drive control unit drives and controls the electric actuator that is the drive member 23b. When a hydraulic cylinder is used instead of the electric actuator, the controller CR includes, for example, a hydraulic pump and a control valve, and the hydraulic cylinder is driven and controlled by the operation of the hydraulic pump and the control valve.

  The detection unit SE2 is connected to the control unit CR. As the detection unit SE2, when changing from the retracted posture to the deployed posture, a sensor for detecting the stop of the wheel loader 40, a sensor for detecting the parking switch ON, a sensor for detecting the door opening / closing switch ON, and a deployment switch of the lifting device main body 21 Sensors that detect ON are used alone or in any combination.

  When the detection unit SE2 is changed from the deployed posture to the retracted posture, the load sensor of the driving member 23b, the camera, the seating sensor provided in the driver's seat in the driver's cab 30, the seat belt wearing sensor, the key switch (engine start A sensor or the like that detects ON) is used alone or in any combination.

  Next, the operation of the lifting device 20 will be described. First, the retracted posture will be described with reference to FIGS.

  As shown in FIGS. 3 and 4, in the retracted posture, the lifting device main body 21 is in a standing state such that the first end 21 </ b> A is located on the upper side and the second end 21 </ b> B is located on the lower side. ing.

  In this retracted position, the drive member 23b of the support member 23 is in a contracted state. As a result, the first member 21b is inserted into the pipe portion 21ca of the second member 21c by a considerable amount, and the side member 21d is in a contracted state. The auxiliary link member 21f has a rhombus shape and is in a contracted state. Therefore, each of the distance between the first step part 21a1 and the second step part 21a2, the distance between the second step part 21a2 and the third step part 21a3, and the distance between the third step parts 21a3 is stored. The posture is smaller than the distance between the step portions 21a connected to the first member 21b.

  In the retracted posture, each of the side member 21d and the connecting piece 22b is inclined with respect to the first link piece 22c of each of the one link member 22e1 and the other link member 22e2. Moreover, the side member 21d and the connection piece 22b are parallel, and each 1st link piece 22c is also parallel. For this reason, the first rectangular link mechanism (side member 21d, connecting piece 22b, first link piece 22c) has a parallelogram shape other than a rectangle.

  In the retracted posture, each of the gripping portion 22a and the connecting piece 22b is inclined with respect to the second link piece 22d of each of the one link member 22e1 and the other link member 22e2. Further, the gripping portion 22a and the connecting piece 22b are parallel, and the second link pieces 22d are also parallel to each other. For this reason, the second rectangular link mechanism (gripping portion 22a, connecting piece 22b, second link piece 22d) has a parallelogram shape other than a rectangle.

  In the retracted posture, the first link piece 22c and the second link piece 22d of one link member 22e1 extend in a direction crossing each other. Further, the first link piece 22c and the second link piece 22d of the other link member 22e2 extend in a direction crossing each other.

  As described above, each of the first and second rectangular link mechanisms has a parallelogram shape other than a rectangle and is in a folded state. In this retracted posture, the upper end 22a1 of the grip portion 22a is located below the step 30b attached to the cab 30.

  When shifting from the retracted position to the deployed position, the drive member 23b is extended. As a result, the lifting device main body 21 is in an unfolded posture such that the second end 21B is positioned on the laterally outer side of the vehicle body with respect to the first end 21A.

  At this time, the side member 21d rotates with respect to the vehicle body about the rotation shafts 21ba and 21gb. The second member 21c slides relative to the first member 21b, and the side member 21d extends. This increases the distance between the first step portion 21a1 and the second step portion 21a2, and the auxiliary link member 21f is deformed from a rhombus shape to a linear shape.

  When the auxiliary link member 21f is deformed into a linear shape, the third step portion 21a3 between the first step portion 21a1 and the second step portion 21a2 also moves. Thereby, each of the distance of the 3rd step part 21a3 and the 1st step part 21a1, the distance of the 3rd step part 21a3 and the 2nd step part 21a2, and the distance of 3rd step part 21a3 becomes large.

  Further, the second member 21c slides with respect to the first member 21b, whereby the connecting member 21e rotates with respect to the second member 21c and rises. In conjunction with the rising operation of the connecting member 21e, the first link piece 22c and the second link piece 22d of the other link member 22e2 also rotate and rise with respect to the second member 21c.

  In this way, the handrail portion 22 shifts from the folded state to the rising state in conjunction with the rising operation of the connecting member 21e. As a result, the lifting device main body 21 shifts from the retracted posture to the deployed posture.

  In the deployed posture, the drive member 23b of the support member 23 is in an extended state. Thereby, the length in which the first member 21b is inserted into the tube portion 21ca of the second member 21c is shorter than that in the retracted posture, and the side member 21d is in an extended state.

  Further, the auxiliary link member 21f has a linear shape and is in an extended state. Therefore, each of the distance between the first step part 21a1 and the third step part 21a3, the distance between the second step part 21a2 and the third step part 21a3, and the distance between the third step parts 21a3 is developed. The posture is substantially the same as the distance between the step portions 21a connected to the first member.

  In the deployed posture, each of the side member 21d and the connecting piece 22b is substantially orthogonal to the first link piece 22c of each of the one link member 22e1 and the other link member 22e2. Moreover, the side member 21d and the connection piece 22b are parallel, and each 1st link piece 22c is also parallel. For this reason, the first rectangular link mechanism has a substantially rectangular shape.

  In the deployed posture, each of the gripping portion 22a and the connecting piece 22b is substantially orthogonal to the second link piece 22d of each of the one link member 22e1 and the other link member 22e2. Further, the gripping portion 22a and the connecting piece 22b are parallel, and the second link pieces 22d are also parallel to each other. For this reason, the second rectangular link mechanism has a substantially rectangular shape.

  In the deployed posture, the first link piece 22c and the second link piece 22d of the one link member 22e1 are positioned on the same straight line. The first link piece 22c and the second link piece 22d of the other link member 22e2 are located on the same straight line.

  When shifting from the deployed position to the retracted position, the drive member 23b is contracted. As a result, an operation opposite to the shift from the retracted posture to the deployed posture is generated, and the lifting device main body 21 is in the retracted posture.

  Next, the opening / closing control of the door 10 and the storage / deployment control of the lifting device 20 when the operator gets on and off the wheel loader 40 will be described. First, control when the operator gets on the wheel loader 40 will be described with reference to FIGS.

  FIG. 5 is a functional block diagram for explaining operations of the lifting device and the door in the wheel loader according to the embodiment of the present invention. 6 to 8 are flowcharts showing the door opening / closing operation and the lifting / lowering operation of the lifting device when the operator gets on.

  The wheel loader 40 is stopped, and the lifting device main body 21 is in a deployed state. In this state, as shown in FIG. 5 and FIG. 6, it is detected by the sensor mounted on the wheel loader 40 that the operator has approached the wheel loader 40 or has been placed on the lifting device main body 21, and the identity authentication is performed. Is performed (step S1a). This sensor is for example a camera, a microphone, a contact sensor or a smart key receiver.

  When the sensor is a camera, for example, the control unit CR performs authentication by collating an operator image captured by the camera with operator information (image) stored in the storage unit MR.

  When the sensor is a microphone, the control unit CR performs authentication by comparing the operator's voice print collected by the microphone with operator information (voice print) stored in the storage unit MR.

  Further, when the sensors are contact sensors provided in the lifting device 20, the control unit CR performs authentication by checking operator characteristics obtained by these sensors with operator information stored in the storage unit MR. .

  When the sensor is a smart key receiver, the control unit CR sends the smart key information (operator detection information) received by the smart key receiver to the operator information (smart key information) stored in the storage unit MR. ) Is verified.

  It is determined whether or not the operator (or smart key) matches the information of the operator (or smart key) stored in the storage unit MR by the authentication (step S2a).

  If the operator (or smart key) does not match the operator (or smart key) stored in the storage unit MR as a result of the authentication, the operator is notified that the information does not match, for example, by a speaker sound or buzzer sound. (Step S3a). If the operator (or smart key) matches the operator (or smart key) stored in the storage unit MR as a result of the authentication, the operator is notified of the match by, for example, speaker sound or buzzer sound ( Step S4a).

  Thereafter, whether or not there is an obstacle within the opening / closing operation range of the door 10 is detected by a sensor (for example, a camera) and determined by the control unit CR (step S5a). If it is determined that there is an obstacle, the operator is informed, for example, by a speaker sound or a buzzer sound, that the door 10 cannot be opened (step S6a).

  If it is determined that there is no obstacle, the operator is notified of the operation of opening the door 10 by, for example, a speaker sound or a buzzer sound (step S7a). Then, operation which opens the door 10 by operating the door drive part 11 is performed (step S8a).

  The opening operation of the door 10 is performed by contracting the door driving unit 11 (for example, a hydraulic cylinder) as shown in FIG.

  Thereafter, whether or not the door drive unit 11 has an obstacle in opening and closing the door 10 is detected by, for example, a load sensor of the drive unit and determined by the control unit CR (step S8a1). When an overload is not applied to the door drive unit 11, the operation of opening the door 10 is continued. Moreover, when the overload is acting on the door drive part 11, the operation | movement of the door drive part 11 is stopped (step S8a2).

  Then, whether or not the operation for opening the door 10 is completed is determined by the control unit CR using the length of the door driving unit 11 or the like (step S8a3). If the operation to open the door 10 is not completed, the operator is notified by voice or the like that the operation to open the door 10 due to overload cannot be performed (step S8a4).

  When the operation for opening the door 10 is completed, the operator is notified that the operation for opening the door 10 has been completed (step S8a5). When the operation of opening the door 10 is completed, the operator ascends the elevating device 20 while grasping the handrail portion 22, and after entering the cab 30 through the opened door 10 (get on). .

  As shown in FIGS. 5 and 7, it is detected by the boarding sensor whether or not the operator gets in the cab 30 and is determined by the control unit CR (step S9a). This boarding sensor is, for example, a camera, a load sensor for the driving member 23b, or the like.

  When the boarding sensor is a camera, for example, the control unit CR determines whether or not the operator has boarded based on an image of the operator photographed by the camera. When the boarding sensor is, for example, a load sensor of the driving member 23b, the control unit CR determines whether or not the operator has boarded based on a signal from the load sensor that detects the load received by the elevating device 20.

  When it is determined that the operator has boarded, whether or not the operator is in a safe state is detected by the state detection sensor, and is determined by the control unit CR (step S10a). This state detection sensor is, for example, a seating sensor for an operator seat, a seatbelt wearing sensor, a retracting / deploying switch for the lifting device 20, and the like.

  When the state detection sensor is, for example, a seating sensor, the control unit CR determines whether or not the operator is in a safe state based on a signal from the seating sensor that detects that the operator is seated on the operator seat.

  When the state detection sensor is, for example, a seat belt mounting sensor, the control unit CR determines whether or not the operator is in a safe state based on a signal from the mounting sensor that detects that the seat belt is mounted.

  When the state detection sensor is, for example, a storage / deployment switch of the lifting device 20, the controller CR determines whether or not the operator is in a safe state based on a signal that the storage / deployment switch of the lifting device 20 is turned on. .

  When it is determined that the operator is in a safe state, it is detected by a sensor (for example, a camera) whether or not there is an obstacle in the operation range for closing the door 10, and is determined by the control unit CR (step S11a). . If it is determined that there is an obstacle, the operator is informed, for example, by a speaker sound or a buzzer sound, that the operation of closing the door 10 cannot be performed (step S12a).

  If it is determined that there is no obstacle, the operator is notified of the operation of closing the door 10 by, for example, a speaker sound or a buzzer sound (step S13a). Then, operation which closes the door 10 by operating the door drive part 11 is performed (step S14a).

  The operation of closing the door 10 is performed by extending the door driving unit 11 (for example, a hydraulic cylinder) as shown in FIG.

  Thereafter, whether or not an overload is applied to the door driving unit 11 is detected by the load sensor, and is determined by the control unit CR (step S15a). When an overload is applied to the door drive unit 11, the operation of closing the door 10 is stopped (step S17a), and it is notified that the operation of closing the door 10 cannot be performed (step S18a). If no overload is applied to the door drive unit 11, the operation of closing the door 10 is continued (step S16a). When the door 10 is completely closed, this is notified.

  As shown in FIGS. 5 and 8, a sensor (for example, a camera) detects whether there is an obstacle on the lifting device 20 and in the range from the deployed posture to the retracted posture of the lifting device 20, and is controlled by the control unit CR. It is determined (step S19a). If it is determined that there is an obstacle, the operator is informed that the retracting operation of the elevating device 20 cannot be performed by, for example, a speaker sound or a buzzer sound (step S20a).

  If it is determined that there is no obstacle, the operator is notified of the storage operation of the lifting device 20 being performed by, for example, speaker sound or buzzer sound (step S21a). Thereafter, the lifting device 20 is moved to the retracted position by operating the lifting device 20 (step S22a). The state of transition of the lifting device 20 to the retracted posture is displayed on a monitor (display device) attached to the wheel loader 40. It is set so that the lock / parking brake of the work machine 33 is not turned off until the lifting device 20 is in the retracted position.

  It is determined whether or not the lifting device 20 is in the retracted position (step S23a). When the lifting / lowering device 20 is in the retracted posture, the operator is notified of the lifting / lowering device 20 being in the retracted posture by, for example, voice of a speaker or buzzer sound (step S24a). When the lifting device 20 is in the retracted posture, the lock / parking brake of the work machine 33 can be turned off (step S25a).

  Next, control when the operator gets off the wheel loader 40 will be described with reference to FIGS. 5, 9, and 10.

  FIG. 9 and FIG. 10 are flowcharts showing the door opening / closing operation and the lifting / lowering device storing / deploying operation when the operator gets off the vehicle.

  As shown in FIGS. 5 and 9, first, the wheel loader 40 stops (step S1b). In this state, the door 10 of the cab 30 is closed, and the lifting device 20 is in the retracted posture.

  It is determined whether or not the parking brake is ON and the work implement lock is ON (step S2b). When both the parking brake and the lock of the work machine are not ON, the fact is notified to the operator by, for example, a speaker sound or a buzzer sound (step S3b).

  When both the parking brake and the lock of the work implement are ON, it is detected by a sensor (for example, a camera) whether or not there is an obstacle in the range from the retracted posture to the deployed posture of the lifting device 20; It is discriminated by the controller CR (step S4b). At this time, at least one of ON / OFF of the getting-off switch, the detection result of the seating sensor, and the detection result of the seat belt wearing sensor is determined. And when it is determined that there is no obstacle, when the getting-off switch is ON, when the seating sensor detects that the operator is not seated in the driver's seat, or when the seatbelt mounting sensor detects the seat When it is detected that the belt is not attached, the operator is notified of, for example, a speaker sound or a buzzer sound that the lifting device 20 is deployed from the retracted posture to the deployed posture (step S5b).

  Thereafter, the lifting device 20 is deployed from the retracted posture to the deployed posture (step S6b). It is determined whether or not the lifting / lowering device 20 has been deployed (step S7b). When the deployment of the lifting device 20 is completed, the operator is notified of the start of the operation of opening the door 10 by, for example, a speaker sound or a buzzer sound (step S8b). Thereafter, an operation of opening the door 10 is performed (step S9b).

  The opening operation of the door 10 is performed by contracting the door driving unit 11 (for example, a hydraulic cylinder) as shown in FIG.

  As shown in FIGS. 5 and 10, whether there is an obstacle within the range of the operation of opening the door 10 or whether the operation of opening the door 10 is overloaded is determined by a sensor (for example, a camera or a load). Sensor) and discriminated by the controller CR (step S10b). When it is determined that there is an obstacle or an overload, the operation of opening the door 10 is stopped (step S12b), and the operator is informed that the door 10 cannot be opened by, for example, a speaker sound or a buzzer sound ( Step S13b).

  If it is determined that there is no obstacle or overload, the operation of opening the door 10 is continued and the door 10 is opened (step S11b). When the operation of opening the door 10 is completed, the operator goes out of the cab 30 (gets off) through the opened door 10 and gets off the lifting device 20. At this time, whether or not the operator has gone out of the cab 30 is detected by a sensor, and is determined by the controller CR (step S14b). This sensor is, for example, a camera, a load sensor of the driving member 23b, a smart key, or the like.

  When the sensor is, for example, a camera, the control unit CR determines whether or not the operator has got off based on the operator's image taken by the camera. When the sensor is, for example, a load sensor of the drive member 23b, the control unit CR determines whether or not the operator has got off based on a load sensor signal that detects a load received by the lifting device 20. Further, when the sensor is a smart key, for example, the control unit CR determines whether or not the operator has got off based on the smart key receiver detecting that the smart key carried by the operator has gone out of the cab 30. Is determined by

  When it is determined that the operator has exited, whether there is an obstacle within the operation range for closing the door 10 is detected by a sensor (for example, a camera) and determined by the control unit CR (step S15b). If it is determined that there is an obstacle, the operator is informed that the operation of closing the door 10 cannot be performed by, for example, a speaker sound or a buzzer sound (step S16b).

  If it is determined that there is no obstacle, the operator is notified of the operation of closing the door 10 by, for example, a speaker sound or a buzzer sound (step S17b). Then, operation which closes the door 10 by operating the door drive part 11 is performed (step S18b).

  The operation of closing the door 10 is performed by extending the door driving unit 11 (for example, a hydraulic cylinder) as shown in FIG.

  Thereafter, it is detected by a sensor (for example, a camera or a load sensor) whether there is an obstacle within the range of the operation of closing the door 10, or whether there is an overload in the operation of closing the door 10, and the control unit It is determined by CR (step S19b). If it is determined that there is an obstacle or an overload, the operation of closing the door 10 is stopped (step S21b), and the operator is informed that the door 10 cannot be closed by, for example, a speaker sound or a buzzer sound ( Step S22b).

  If it is determined that there is no obstacle or overload, the operation of closing the door 10 is continued and the door 10 is closed (step S20b).

  As shown in FIG. 9, when it is determined in step S4b that there is an obstacle, it is determined whether or not the lifting device 20 can be deployed in the small deployment mode (step S23b). If the deployment in the small deployment mode cannot be performed, the operator is notified of the fact that the deployment operation in the small deployment mode cannot be performed by, for example, a speaker sound or a buzzer sound (step S24b).

  If deployment in the small deployment mode is possible, the operator is notified of the deployment operation in the small deployment mode by, for example, a speaker voice or a buzzer sound (step S25b). Thereafter, switching to the small deployment mode is performed (step S26b).

  When deploying in the small deployment mode, a sensor (for example, a camera or a load sensor) detects whether there is an obstacle within the range of the small deployment operation or whether there is an overload in the operation of opening the door 10. Is discriminated by the controller CR (step S27b). If it is determined that there is an obstacle or an overload, the small deployment operation is stopped (step S29b), and the operator is notified of the fact that the small deployment operation cannot be performed by, for example, a speaker sound or a buzzer sound (step S30b). If it is determined that there is no obstacle or overload, the small deployment operation is continued, and the lifting device 20 enters the small deployment state (step S28b).

  The lifting / lowering of the lifting / lowering device is performed, for example, by turning on / off a lifting / lowering switch of the lifting / lowering device.

Next, a modified example of the door 10 will be described with reference to FIG.
FIG. 11 is a schematic plan view showing an opening / closing operation of a modified example of the door used in the wheel loader according to the embodiment of the present invention.

  In the above embodiment, the case where the door 10 is a foldable door 10 has been described. However, the door 10 according to this embodiment recognizes an operator and automatically opens (or closes). Any type of door can be used. For example, as shown in FIG. 11, the door 10 may be a sliding door. The sliding door 10 is composed of, for example, a single plate. The door opening 30a can be opened and closed by moving the door 10 in the front-rear direction. The sliding operation of the door 10 is performed by the drive unit AC. The drive unit AC may be a hydraulic cylinder or a motor.

  Since the configuration of the sliding door 10 other than the above is substantially the same as the configuration of the folding door 10 shown in FIG. 2, the same elements are denoted by the same reference numerals, and the description thereof will not be repeated.

  In the above embodiment, a case has been described in which an operation of automatically closing the door 10 by detecting whether the operator has gone out of the cab 30 (gets off the vehicle) or not is performed. An operation of automatically closing the door 10 by detecting whether or not the user has moved away from the top may be performed.

Next, the effect of this Embodiment is demonstrated.
According to the present embodiment, as shown in FIG. 2, the door drive unit 11 that automatically opens the door 10 based on the detection of the operator by the detection unit SE1 is provided. For this reason, it is not necessary for the operator to manually open the large door 10 of the cab 30 while holding the handrail portion 22 on the lifting device main body 21. For this reason, it becomes easy for the operator to get into the cab 30 from the lifting device 20.

  Further, according to the present embodiment, as shown in FIG. 2, the entire opening / closing locus of the door 10 overlaps with the step 30 b fixed to the cab 30 in a plan view. For this reason, the door 10 does not protrude step 30b in plan view when opening and closing. Therefore, the door 10 during the opening / closing operation is prevented from colliding with the operator on the lifting device main body 21.

  Moreover, according to this Embodiment, as FIG. 2 shows, the door 10 is a foldable door. For this reason, it can prevent easily that the door 10 protrudes from step 30b in planar view at the time of the opening and closing.

  Further, according to the present embodiment, as shown in FIG. 2, the control unit CR is based on the result of collating the operator detection information detected by the detection unit SE1 with the operator information stored in the storage unit MR. The door drive unit 11 is controlled. This makes it possible to perform personal authentication of the operator.

  Further, according to the present embodiment, the detection unit SE1 detects that the operator has been placed on the lifting device 20. As a result, the door 10 can be opened at the timing when the operator is placed on the lifting device.

  Further, according to the present embodiment, the door 10 is automatically closed after the operator goes out of the cab 30. This eliminates the need for the operator to manually close the large door 10 of the cab 30 while getting out of the cab 30 and being on the lifting device main body 21. For this reason, it becomes easy for the operator to get down from the cab 30 to the lifting device 20.

  According to the present embodiment, as shown in FIG. 1, the solar panel 35 is disposed on the upper surface of the cab 30. As a result, even when the engine of the wheel loader 40 is stopped, the air conditioner can be operated with the electric power generated by the solar panel 35 and the air in the cab 30 can be conditioned.

  Further, according to the present embodiment, as shown in FIGS. 3 and 4, the handrail portion 22 is configured such that the gripping portion 22a is separated from the lifting device body 21 in the deployed posture and the gripping portion 22a in the retracted posture. Is in a folded state approaching the lifting device main body 21. Thus, since the handrail portion 22 is folded in the retracted posture, the protrusion dimension that the handrail portion 22 protrudes outward in the left-right direction of the wheel loader 40 can be suppressed to be small. For this reason, it is possible to avoid the handrail portion 22 protruding laterally in the retracted posture from interfering with an obstacle.

  Further, according to the present embodiment, as shown in FIG. 3, the upper end 22a1 of the gripping portion 22a is located below the step 30b in the retracted posture. For this reason, it becomes easy to store the lifting / lowering device 20 in the region directly under the step 30b in the retracted posture. Thereby, it is suppressed that the raising / lowering apparatus 20 protrudes outside the left-right direction of the wheel loader 40 rather than step 30b in planar view. Therefore, it is possible to avoid the handrail portion 22 from interfering with an obstacle in the retracted posture.

  Further, according to the present embodiment, as shown in FIGS. 3 and 4, the handrail portion 22 includes a grip portion 22a, a connecting piece 22b, and a pair of link members 22e1 and 22e2. These constitute a rectangular link mechanism. By deforming the rectangular link mechanism, the handrail portion 22 can be folded.

  Further, according to the present embodiment, as shown in FIGS. 3 and 4, the side member 21d is slidable with respect to the first member 21b supported rotatably on the vehicle body and the first member 21b. And a second member 21c attached to the. By sliding the second member 21c with respect to the first member 21b, the length of the side member 21d can be changed. For this reason, in the deployed posture, the side member 21d can be extended long from the vicinity of the ground to a high place. Further, in the retracted posture, by shortening the side member 21d, an appropriate space can be secured between the second end portion 21B of the lifting device main body and the ground.

  The first link piece 22c of the other link member 22e2 is rotatably attached to the first member 21b so as to be slidable with respect to the second member 21c. Thereby, even if the second member 21c slides with respect to the first member 21b, the first link piece 22c of the other link member 22e2 can also slide with respect to the second member 21c. It can function as a linkage mechanism appropriately.

  Further, according to the present embodiment, as shown in FIGS. 3 and 4, the connection member 21e is rotatably supported by the second member 21c at one end and the other link member 22e2 at the other end. The second link piece 22d is rotatably attached to the grip portion 22a. As a result, the connecting member 21e rotates relative to the second member 21c or tilts in conjunction with the movement of the second member 21c sliding relative to the first member 21b. In conjunction with the rising / tilting operation of the connecting member 21e, the second link piece 22d of the other link member 22e2 also rotates relative to the second member 21c or rises or tilts. As a result, the handrail portion 22 can transition between the rising state and the folded state.

  Further, according to the present embodiment, as shown in FIGS. 3 and 4, the support member 23 has one end 23A attached to the vehicle body and the other end 23B attached to the second member 21c so as to be rotatable. ing. Further, the distance between the one end 23A and the other end 23B can be expanded and contracted by the drive member 23b. By extending and retracting the support member 23 using the drive member 23b, the second member 21c can be slid with respect to the first member 21b, and the lifting device body 21 is shifted between the retracted posture and the deployed posture. It becomes possible to make it.

  Further, according to the present embodiment, as shown in FIGS. 3 and 4, the support member 23 includes the drive member 23 b that can expand and contract the distance between the one end 23 </ b> A and the other end 23 </ b> B. Yes. The drive member 23b can automatically move the lifting device body 21 between the retracted posture and the deployed posture.

  Further, according to the present embodiment, as shown in FIG. 3 and FIG. 4, the plurality of step units 21 a include the first step unit 21 a 1, the second step unit 21 a 2, and the third step unit 21 a 3. ing. The first step portion 21a1 is attached to the second end 21B side of the first member 21b among the plurality of step portions 21a. The 2nd step part 21a2 is attached to the 2nd end 21B side of the 2nd member 21c among a plurality of step parts 21a. The third step portion 21a3 is slidably attached to the second member 21c between the first step portion 21a1 and the second step portion 21a2. Thereby, when the 2nd member 21c slides with respect to the 1st member 21b, the 3rd step part 21a3 can also be made to slide with respect to the 2nd member 21c in response to the slide.

  When the second member 21c slides with respect to the first member 21b, the distance between the third step portion 21a3 and the first step portion 21a1 and the third step portion 21a3 and the second step portion according to the sliding amount. Each of the distance between 21a2 and the distance between 3rd step part 21a3 changes. According to the present embodiment, as shown in FIGS. 3 and 4, between the third step portion 21a3 and the first step portion 21a1, between the third step portion 21a3 and the second step portion 21a2, An auxiliary link member 21f is provided between each of the three step portions 21a3. By this auxiliary link member 21f, the distance between the third step portion 21a3 and the first step portion 21a1, the distance between the third step portion 21a3 and the second step portion 21a2, and the distance between the third step portions 21a3. Each of the distances can be adjusted appropriately.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  10 door, 20 lifting device, 10a, 10b door panel, 10c, 10d, 11a, 11b, 21ba rotating shaft, 10e slide piece, 11 door drive unit, 21 lifting device body, 21a step unit, 21a1 first step unit, 21a2 first 2 step part, 21a3 3rd step part, 21a4 uppermost step part, 21b 1st member, 21c 2nd member, 21ca pipe part, 21cb opening, 21cc protruding part, 21d lateral member, 21e, 23a connecting member, 21f Link member, 21g Rotating member, 21A 1st end part, 21B 2nd end part, 22 Handrail part, 22a Grasping part, 22a1 Upper end, 22b Connection piece, 22b1 One end, 22b2 The other end, 22c 1st link piece, 22d Second link piece, 22e1 One link member, 22e2 The other Link member, 23 support member, 23A one end, 23B other end, 23b drive member, 23c fixture, 30 cab, 30a door opening, 30aa guide rail, 30b step, 31 front frame, 32 rear body, 32a Hydraulic oil tank, 32b Engine room, 33 Working machine, 33a Boom, 33b Bucket, 33d Bell crank, 33e Bucket cylinder, 33f Link, 34a Front wheel, 34b Rear wheel, 35 Solar panel, 40 Wheel loader, AC drive, CR Control unit, MR storage unit, SE1, SE2 detection unit.

Claims (7)

A lifting device;
A cab located above the lifting device and having a door;
A detection unit for recognizing an operator;
A work vehicle comprising: a door driving unit that automatically opens the door based on detection of an operator by the detection unit. The cab has a step located directly below the door;
The work vehicle according to claim 1, wherein an entire opening / closing locus of the door overlaps with the step in a plan view.   The work vehicle according to claim 1, wherein the door is a foldable door. A storage unit for storing operator information in advance;
The control part which controls the said door drive part further based on the result which collated the detection information of the operator detected by the said detection part with the operator information memorize | stored in the said memory | storage part was provided. The work vehicle according to any one of the above.   The work vehicle according to any one of claims 1 to 3, wherein the detection unit detects that an operator has been placed on the lifting device.   The work vehicle according to any one of claims 1 to 5, wherein the door is automatically closed after an operator goes out of the cab.   The work vehicle according to any one of claims 1 to 6, further comprising a solar panel disposed on an upper surface of the cab.

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