Lever device and work machine equipped with same

Abstract

Provided is a lever device (27) that can adequately apply the biasing force of a tension spring (47) to a lever (30) even when the rotation angle of a movable body (32) is small.　The lever device (27) is equipped with a switching mechanism (33) that switches the direction in which the biasing force of the tension spring acts on the lever, which is rotatably supported on the movable body via a second support shaft (72) and serves to rotate the movable body, wherein: the switching mechanism has a rotating member (69), which rotates together with the lever and is provided with a first spring hooking part (74) and a first engagement part (75) positioned so that the second support shaft is located therebetween when viewed from the axial direction of the second support shaft, and a link (76), which is rotatably supported on the movable body via a third support shaft (77) and provided with a second spring hooking part (80) and a second engagement part (81) positioned so that the third support shaft is located therebetween when viewed from the axial direction of the third support shaft; and the link is disposed such that the first engagement part and the second engagement part engage with each other, and the second engagement part moves and rotates around the third support shaft as the first engagement part moves due to the rotation of the rotating member around the second support shaft, thereby moving the second spring hooking part to the same side to which the first spring hooking part moves.

Description

[Technical Field]

[0001] The present invention relates to a lever device and a work machine equipped with the same. [Background technology]

[0002] BACKGROUND ART A lever device disclosed in Patent Document 1 is known in the prior art.

[0003] The lever device disclosed in Patent Document 1 includes a movable body rotatably supported on a fixed body (support bracket) fixed to a machine body between a lowered position and a raised position rotated upward from the lowered position, and a lever for rotating the movable body. The lever can be moved between a depressed position and a raised position, which is raised from the depressed position. By operating the lever between the depressed position and the raised position, the movable body is rotated between the lowered position and the raised position. The lever is held in the depressed position and the raised position by the biasing force of a tension spring. The direction of the biasing force of the tension spring is switched by a switching mechanism. The switching mechanism switches the direction of the biasing force of the tension spring so that the biasing force acts in a direction that pulls the lever down in the depressed position and in a direction that pulls the lever up in the raised position. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2019-116753 Summary of the Invention [Problem to be solved by the invention]

[0005] However, depending on the location where the lever device is installed, it may not be possible to ensure a large rotation angle (amount of rotation) of the movable body. If the rotation angle of the movable body is small, the rotation angle of the lever cannot be made large, making it difficult to ensure that the biasing force of the tension spring is sufficiently applied to the lever at the depressed and raised positions.

[0006] In view of the above problems, the present invention aims to provide a lever device and a work machine equipped with the same that can apply the biasing force of a tension spring to a lever even when the rotation angle of the movable body is small. [Means for solving the problem]

[0007] A lever device according to one aspect of the present invention includes a fixed body, a movable body rotatably supported on the fixed body via a first support shaft, a lever for rotating the movable body around the first support shaft, the lever being rotatably supported on a second support shaft provided on the movable body at a pressed-down position and a pulled-up position rotated upward from the pressed-down position, a tension spring for biasing the lever, and a switching mechanism for switching the direction of the biasing force of the tension spring between the pressed-down position and the pulled-up position so that the biasing force of the tension spring acts in a direction to pull down the lever at the pressed-down position and acts in a direction to pull up the lever at the pulled-up position, the switching mechanism being a rotating member that rotates integrally with the lever around the second support shaft, and a link rotatably supported by the movable body via a third support shaft, the link having a second spring hook portion and a second engaging portion arranged at positions sandwiching the third support shaft when viewed in the axial direction of the third support shaft. The tension spring is hung across the first spring hook portion and the second spring hook portion, and the link is arranged so that the first engaging portion and the second engaging portion engage with each other. The tension spring is configured so that the second engaging portion moves and rotates around the third support shaft as the first engaging portion moves due to the rotation of the rotating member around the second support shaft, moving the second spring hook portion to the same side as the first spring hook portion moves.

[0008] One of the first engagement portion and the second engagement portion may be formed by a pin parallel to the second support shaft or the third support shaft, and the other of the first engagement portion and the second engagement portion may be formed by a groove or hole into which the pin can be inserted.

[0009] If the side to which the first spring hook portion moves when the lever is pulled up and operated is defined as a first side, and the side opposite the first side is defined as a second side, then when the lever is pulled up and the rotating member rotates around the second support shaft, the first spring hook portion moves to the first side, and the first engagement portion and the second engagement portion move to the second side, so that the second spring hook portion moves to the first side; and when the lever is pushed down and the rotating member rotates around the second support shaft, the first spring hook portion moves to the second side, and the first engagement portion and the second engagement portion move to the first side, so that the direction of the biasing force of the tension spring acting on the lever switches between a direction that pulls the lever down and a direction that pulls the lever up.

[0010] The movable body may be rotatable between a lowered position and a raised position rotated upward from the lowered position around the first support shaft, the depressed position of the lever is a position corresponding to the lowered position of the movable body, the lever may be operable to a raised operation position which is the position when the movable body is operated to the raised position, and the raised position of the lever may be a position where the lever is further pulled up from the raised operation position relative to the movable body which is in the raised position.

[0011] The lever device comprises a guide body provided on the fixed body, and a guide plate having a guide groove into which the guide body fits and which rotates integrally with the lever around the second support shaft, the guide groove having a first groove portion that restricts the movable body in the lowered position from rotating in the raising direction and allows the lever to rotate in the pulling-up direction, a second groove portion that allows the movable body to rotate by operating the lever, and a third groove portion that restricts the movable body in the raised position from rotating in the raising direction and allows the lever to rotate around the second support shaft, and the third groove portion may have a locking portion that restricts the movable body from rotating in the lowered direction from the raised position when the lever is in the pulled-up position.

[0012] The movable body may have a support tube that supports the second support shaft so that it can rotate freely around its axis, the lever may be attached to the second support shaft on one side of the support tube in the axial direction, and the guide plate may be fixed to the second support shaft on the other side of the support tube in the axial direction.

[0013] A work machine according to one aspect of the present invention includes the lever device.

[0014] The lever may be an operation lock lever that switches an actuator provided in the work machine between an operable state and an inoperable state. [Effects of the Invention]

[0015] According to the lever device having the above configuration, the second spring hook portion moves to the side to which the first spring hook portion moves due to the rotation of the link accompanying the movement of the first engagement portion by operating the lever, so that the central axis of the tension spring can be moved to an appropriate position away from the center of the second support shaft in the pressed-down position and the pulled-up position, and the biasing force of the tension spring on the lever can be applied even when the rotation angle of the movable body is small. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 2 is an overall side view of the work machine. [Figure 2] FIG. 2 is a perspective view of the aircraft body and the driving section. [Figure 3] FIG. 2 is a perspective view showing a state in which the control device is supported on the support frame. [Figure 4] FIG. 1 is a side view of the controls in the lowered position without the console cover. [Figure 5] FIG. 1 is a side view of the control device in the raised position without the console cover. [Figure 6] FIG. 2 is a perspective view of the control device with the console cover removed. [Figure 7] FIG. 2 is a perspective view of the control device with the console cover removed. [Figure 8] FIG. 2 is a perspective view of the control device with the console cover removed. [Figure 9] FIG. [Figure 10] FIG. [Figure 11] FIG. [Figure 12] FIG. 2 is an exploded perspective view of the switching mechanism and its surroundings. [Figure 13] FIG. [Figure 14] FIG. 10 is a schematic side view of the movable body, lever, and switching mechanism in the lowered position. [Figure 15] FIG. 15 is an enlarged view of the switching mechanism in FIG. [Figure 16] 10 is a schematic side view of the movable body, the lever, and the switching mechanism during rotation. FIG. [Figure 17] FIG. 17 is an enlarged view of the switching mechanism in FIG. [Figure 18] 10 is a schematic side view of the movable body, the lever, and the switching mechanism during rotation. FIG. [Figure 19] FIG. 19 is an enlarged view of the switching mechanism in FIG. [Figure 20] FIG. 10 is a schematic side view of the movable body, the lever, and the switching mechanism in the raised position. [Figure 21] FIG. 21 is an enlarged view of the switching mechanism in FIG. 20. [Figure 22] 10 is a schematic side view of the lever in the raised position, the movable body in the raised position, and the switching mechanism. FIG. [Figure 23] FIG. 23 is an enlarged view of the switching mechanism in FIG. 22. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings as appropriate.

[0018] 1 is a schematic side view showing the overall configuration of a work machine 1 according to this embodiment. In this embodiment, the work machine 1 is exemplified by a backhoe, which is a rotating work machine.

[0019] As shown in Figure 1, the work machine 1 comprises a machine body (swivel base) 2, a traveling device 3, and a work device 4. The machine body 2 is equipped with a driver's seat 6 where an operator (driver) sits, and a four-poster ROP 15. The ROP 15 is a canopy type with a roof 19.

[0020] In this embodiment, the direction toward the front of an operator seated in the driver's seat 6 of the work machine 1 (the direction of arrow A1 in FIG. 1) will be referred to as the forward direction (the front of the machine body), the direction toward the rear of the operator (the direction of arrow A2 in FIG. 1) will be referred to as the rearward direction (the rear of the machine body), and the direction of arrow A3 in FIG. 1 will be referred to as the front-rear direction (the front-rear direction of the machine body). Additionally, the direction toward the left side of the operator (the front side in FIG. 1) will be referred to as the left, and the direction toward the right side of the operator (the back side in FIG. 1) will be referred to as the right.

[0021] Additionally, the horizontal direction perpendicular to the longitudinal direction A3 will be described as the fuselage width direction. The direction from the center of the fuselage 2 in the width direction toward the right or left will be described as the fuselage width outward direction. In other words, the fuselage width outward direction is the direction away from the fuselage width center of the fuselage 2 in the fuselage width direction. The direction opposite to the fuselage width outward direction will be described as the fuselage width inward direction. In other words, the fuselage width inward direction is the direction approaching the fuselage width center of the fuselage 2.

[0022] As shown in FIG. 1, the traveling device 3 is a crawler-type traveling device that supports the machine body 2 so that it can travel, and includes a traveling frame 3A, a first traveling device 3L provided on the left side of the traveling frame 3A, and a second traveling device 3R provided on the right side of the traveling frame 3A. The first traveling device 3L and the second traveling device 3R are driven by a traveling motor M1 configured as a hydraulic motor (hydraulic actuator). In this embodiment, a crawler-type traveling device 3 is used, but this is not limiting, and a wheel-type traveling device or the like may also be used. A dozer device 7 is attached to the front of the traveling device 3. The dozer device 7 can be driven by a dozer cylinder configured as a hydraulic cylinder (hydraulic actuator).

[0023] As shown in FIG. 1, the machine body 2 has a swivel base 5 made of thick plate material that forms the bottom of the machine body 2 (see FIG. 3). The swivel base 5 is supported on the traveling frame 3A of the traveling device 3 via a swivel bearing 8 so as to be rotatable about a swivel axis X1, which is an axis extending in the vertical direction. The swivel base 5 is driven to rotate about the swivel axis X1 by a swivel motor (not shown). The machine body 2 also has, at its front, a support bracket 9 and a swing bracket 10 that support the working device 4. The support bracket 9 is provided so as to protrude forward from the machine body 2. More specifically, the support bracket 9 is fixed to the front of the swivel base 5 and protrudes forward from the swivel base 5. The swing bracket 10 is attached to the front of the support bracket 9 so as to be swingable about a vertical axis (an axis extending in the vertical direction). A hood 14 that covers mounted items such as a prime mover (engine) is provided on the machine body 2. A weight 25 is disposed at the rear of the machine body 2 to balance the weight with the working device 4. The working machine 1 of this embodiment is a small backhoe, and a driver's seat 6 is disposed above the prime mover (prime mover compartment).

[0024] As shown in FIG. 1 , the work device 4 has a boom 11, an arm 12, and a bucket 13. The base of the boom 11 is pivotally attached to the upper part of the swing bracket 10 so as to be rotatable about a horizontal axis (an axis extending in the width direction of the machine body). The arm 12 is pivotally attached to the tip of the boom 11 so as to be rotatable about the horizontal axis. The bucket 13 is provided at the tip of the arm 12 so as to be capable of scooping and dumping operations. The scooping operation is an operation of swinging the bucket 13 in a direction approaching the boom 11, such as an operation for scooping up earth and sand. The dumping operation is an operation of swinging the bucket 13 in a direction away from the boom 11, such as an operation for dropping (discharging) the scooped earth and sand.

[0025] The swing bracket 10 is capable of swinging by extension and retraction of a swing cylinder (not shown). The boom 11 is capable of swinging by extension and retraction of a boom cylinder C2. The arm 12 is capable of swinging by extension and retraction of an arm cylinder C3. The bucket 13 is capable of scooping and dumping by extension and retraction of a bucket cylinder C4. The swing cylinder, boom cylinder C2, arm cylinder C3, and bucket cylinder C4 are configured as hydraulic cylinders (hydraulic actuators).

[0026] As shown in FIG. 2, the machine body 2 is equipped with a driver's seat 6, a driving section 18 including a driving lever 16 (see FIG. 1) disposed in front of the driver's seat 6, a control device (left control device) 17L disposed to the left of the driver's seat 6, and a control device (right control device) 17R disposed to the right of the driver's seat 6. The driving lever 16 is an operating member for operating the traveling device 3. The control devices 17L and 17R are devices for performing, for example, swinging operations of the boom 11, swinging operations of the arm 12, scooping and dumping operations of the bucket 13, and swinging operations of the machine body 2. A floor 21, on which the operator places their feet, is provided on the upper side of the machine body 2 and in front of the driver's seat 6. The floor 21 is configured, for example, by laying a floor mat on a step board disposed above the swivel base 5 at a distance and supported by the swivel base 5.

[0027] As shown in Fig. 3, the left steering device 17L is attached to a support frame 20. The support frame 20 is a frame that supports the hood 14, driver's seat 6, ROPs 15, etc., and is attached to a member fixed on the rotating base plate 5. The left steering device 17L has a console cover 22, a steering lever (left steering lever) 23L, a remote control valve 24, an armrest 26L, and a lever device 27.

[0028] The console cover 22 is a member that covers the remote control valve 24, lever device 27, etc. The left control lever 23L is located in front of and above the left control device 17L and can be tilted forward and backward and left and right. The remote control valve 24 is a pilot valve that is operated by the left control lever 23L and is located below the left control lever 23L. The remote control valve 24 is housed within the console cover 22. The armrest 26L is a member on which the operator places his or her elbows and is located behind the left control lever 23L.

[0029] 4 to 8, the lever device 27 includes a lever 30, a fixed body 31, a movable body 32, a tension spring 47, a switching mechanism 33, and a guide plate 52. The front portion of the lever 30 protrudes forward from the console cover 22 (see FIG. 2). The base side of the lever 30, the movable body 32, the tension spring 47, and the switching mechanism 33 are covered by the console cover 22.

[0030] As shown in FIG. 2, the right operating device 17R has a console cover , an operating lever (right operating lever) 23R, a remote control valve (not shown), an armrest 26R, a dozer lever 35, and a plurality of switches .

[0031] The console cover 34 is a cover that covers the frame of the right steering device 17R. The frame of the right steering device 17R is attached to the machine body 2. The right steering lever 23R is located at the front and top of the right steering device 17R and can be tilted forward and backward and left and right. The remote control valve is a pilot valve operated by the right steering lever 23R, is located below the right steering lever 23R, and is covered by the console cover 34. The armrest 26R is a member on which the operator places his / her elbows, etc., and is located behind the right steering lever 23R. The dozer lever 35 is a lever that operates the dozer device 7. A plurality of switches 36 are located on the upper surface of the console cover 34 and are switches that operate various devices equipped on the work machine 1.

[0032] The left control lever 23L (remote control valve 24) can operate two control objects (hydraulic actuators) equipped on the work machine 1. For example, the left control lever 23L can operate a swing motor that rotates the machine body 2 (can rotate the machine body 2) and can also operate the arm cylinder C3 (can swing the arm 12).

[0033] The right steering lever 23R can also operate two operation targets (hydraulic actuators) equipped on the work machine 1. For example, the right steering lever 23R can operate the boom cylinder C2 (to swing the boom 11) and the bucket cylinder C4 (to swing the bucket 13).

[0034] As shown in Fig. 2, the driver's section 18 is provided with a seat belt device. The seat belt device includes a belt winding structure 28 having a seat belt with a tongue member attached and a retractor that winds and stores the seat belt, and a buckle member 29 that engages with the tongue member. The belt winding structure 28 is located to the left of the rear and lower part of the driver's seat 6, near the rear of the left steering device 17L. The belt winding structure 28 is attached to a stay member (not shown) provided on the left side of the rear and lower part of the ROPS 15. The buckle member 29 is located to the right of the rear and lower part of the driver's seat 6.

[0035] Next, the lever device 27 of this embodiment will first be briefly described.

[0036] The lever 30 is an operation lock lever (unloading lever) that switches a hydraulic actuator mounted on the work machine 1 between an operable state and an inoperable state, and the lever device 27 is an operation lock lever device (unloading lever device) that includes the operation lock lever. Therefore, the following description will be given assuming that the lever device 27 is an operation lock lever device and the lever 30 is an operation lock lever, but the lever device 27 is not limited to an operation lock lever device (unloading lever device), and the lever 30 is not limited to an operation lock lever (unloading lever). For example, the lever 30 may be an operation lock lever that switches an electric actuator (not shown) provided on the work machine 1 between an operable state and an inoperable state, instead of or in addition to the hydraulic actuator described above. The lever 30 may also be an operation lock lever that outputs a signal to a control device that controls the operation of an actuator provided on the work machine 1, for switching the actuator between an operable state and an inoperable state. The lever 30 is not limited to being used for locking the operation of an actuator, and may be used for other purposes.

[0037] Next, each part of the lever device 27 (operation lock lever 30, fixed body 31, movable body 32, tension spring 47, switching mechanism 33, guide plate 52, etc.) will be described.

[0038] The operation lock lever 30 is a member that rotates (raises and lowers) the movable body 32 up and down. As shown in FIG. 6, the operation lock lever 30 has a lever base 30b, a lever body 30a, and a grip 30c. The lever base 30b is rotatably supported by the movable body 32. In other words, the operation lock lever 30 is rotatably supported by the movable body 32. When the left operating device 17L is in the use state shown in FIGS. 1 and 4, the lever body 30a has a lower portion 30d that is inclined diagonally downward and forward, and a front portion 30e that extends diagonally upward and forward from the front portion of the lower portion 30d. The grip 30c is a portion to be grasped and is provided on the upper portion of the front portion 30e of the lever body 30a. The lever body 30a is also located to the left of the left operating lever 23L (see FIG. 2). When the left operating device 17L is in use, the operation lock lever 30 is in a position that prevents the operator from getting on and off the work machine 1. When the left operating device 17L is in an unused state shown in FIG. 5 , the operation lock lever 30 has rotated rearward and upward together with the movable body 32 from the used state, and is in a position that retracts from the aisle for the operator to get on and off.

[0039] As shown in FIG. 3, the fixed body 31 is attached to the support frame 20. More specifically, the fixed body 31 is fixed to a plurality of rods 37 fixed to the support frame 20 with bolts 38 (see FIG. 9). As shown in FIG. 9, the fixed body 31 has a first member 31A and a second member 31B formed from plate material. The first member 31A forms the upper and front parts of the fixed body 31, and the second member 31B forms the lower part of the rear part of the fixed body 31.

[0040] As shown in FIG. 3 , a support shaft (first support shaft) 39 is provided at the rear and lower part of the fixed body 31 (second member 31B). More specifically, the first support shaft 39 has an axis extending in the width direction of the machine body, and its right end is fixed to the second member 31B and protrudes to the left. A receiving portion 40 is provided at the upper and front part of the fixed body 31 (first member 31A). The receiving portion 40 is configured by fastening an elastic member 40B, such as rubber, to a stay plate 40A fixed to the front part of the first member 31A. A guide body 43 is provided at the upper part and midway in the front-to-rear direction of the fixed body 31 (first member 31A). The guide body 43 is configured with a support pin 44, a roller 46, a washer 45, etc. The support pin 44 is a rod having an axis extending in the width direction of the machine body, and is fixed to the first member 31A while passing through the first member 31A. The support pin 44 protrudes leftward from the first member 31A. The roller 46 is disposed to the left of the first member 31A and is fitted onto the support pin 44 so as to be rotatable about its axis. The washer 45 is fitted onto the support pin 44 to the left of the roller 46 and is prevented from coming off by a retaining pin (not shown). The guide body 43 may be configured without the roller 46 and the washer 45. In other words, the guide body 43 may be formed only by the support pin 44. A mounting stay 41 is fixed to the left surface of the upper rear part of the fixed body 31 (first member 31A). A position restricting member (stopper) 42 is attached to this mounting stay 41.

[0041] 4 to 8, the movable body 32 is provided with the left operation lever 23L, the remote control valve 24, the armrest 26L, the detection switch 51, the operation lock lever 30, the tension spring 47, the switching mechanism 33, and the guide plate 52. The movable body 32 is supported by a first support shaft 39 provided in the fixed body 31 so as to be rotatable about its axis.

[0042] The movable body 32 is rotatable (position changeable) between a lowered position P1 shown in Fig. 4 and a raised position P2 shown in Fig. 5, which is rotated upward from the lowered position P1 around the first support shaft 39. When the movable body 32 is operated to the raised position P2, for example, the working device 4 (boom cylinder C2, arm cylinder C3, bucket cylinder C4) and the machine body 2 (swing motor) become inoperable, and when the movable body 32 is operated to the lowered position P1, the working device 4 can be operated and the machine body 2 can be swung.

[0043] In addition, at the raised position P2, all or the main hydraulic actuators of the work machine 1 (such as the boom cylinder C2, arm cylinder C3, bucket cylinder C4, swing cylinder, dozer cylinder, travel motor M1, swing motor, and hydraulic actuators detachably connected to the service port) may be made inoperable, i.e., no hydraulic oil may be supplied.

[0044] In this embodiment, the belt winding structure 28 is located behind the left steering lever 23L, and the amount of rotation of the movable body 32 when rotating the movable body 32 rearward from the lowered position P1 is limited by the belt winding structure 28. In other words, the rotation angle of the movable body 32 about the first support shaft 39 from the lowered position P1 to the raised position P2 cannot be made large. In this embodiment, this rotation angle is 20°. The rotation angle is not limited to this. For example, the rotation angle can be set to 15° to 25°.

[0045] The operation lock lever 30 can be operated to a depressed position S1 shown in Fig. 4 and a raised position S2 shown in Fig. 5. The depressed position S1 corresponds to the lowered position P1, and the raised position S2 corresponds to the raised position P2.

[0046] In the following description, the direction in which the movable body 32 rotates upward from the lowered position P1 is referred to as the "raising direction," and the direction in which the movable body 32 rotates downward from the raised position P2 is referred to as the "lowering direction." Additionally, the direction in which the operation lock lever 30 rotates upward from the pushed-down position S1 is referred to as the "raising direction," and the direction in which the operation lock lever 30 rotates downward from the pulled-up position S2 is referred to as the "lowering direction."

[0047] As shown in FIGS. 10 and 11 , the movable body 32 has a first wall 53, which is the left wall, and a second wall 54, which is the right wall. The first wall 53 and the second wall 54 are spaced apart in the width direction of the machine body. The movable body 32 has a supported portion 55 that is supported by the first support shaft 39 so as to be rotatable about its axis. The supported portion 55 is formed of a tubular member having an axis extending in the width direction of the machine body and is fixed to the lower part of the first wall 53. More specifically, a lower portion 53a, which is the lower part of the first wall 53, is formed so that its width in the front-to-rear direction narrows as it extends downward, and the supported portion 55 is fixed to the lower part of the lower portion 53a. The left end of the supported portion 55 penetrates and is fixed to the first wall 53. Therefore, the supported portion 55 protrudes to the right from the first wall 53 (the lower part of the lower portion 53a).

[0048] 9, the supported portion 55 is fitted onto the first support shaft 39 from the left so as to be rotatable about its axis. The supported portion 55 is prevented from coming off the first support shaft 39 by a washer 56 and a bolt 58 that is screwed into a screw hole 57 formed in the first support shaft 39. This allows the movable body 32 to be supported on the fixed body 31 (first support shaft 39) so as to be rotatable about an axis that extends in the width direction of the machine body.

[0049] As shown in Figures 10 and 11, an abutment member 63 made of an elastic member is fixed to the front part of the lower end of the second wall portion 54. The abutment member 63 abuts against the receiving portion 40 of the fixed body 31 when the movable body 32 is in the lowered position P1 (see Figure 8). This restricts the rotation of the movable body 32 in the lowering direction. An abutment plate 59 is fixed to the lower part of the rear part of the second wall portion 54. As shown in Figure 5, the abutment plate 59 abuts against the position restricting member 42 of the fixed body 31 when the movable body 32 is in the raised position P2. This restricts the rotation of the movable body 32 in the raised direction.

[0050] As shown in FIG. 10, a support plate 60 is fixed to a midpoint of the supported portion 55 in the width direction of the machine body. The support plate 60 is arranged so that its plate surface faces the width direction of the machine body, and the supported portion 55 penetrates and is fixed to its lower portion. An assist spring 61 is arranged to the right of the support plate 60 in the supported portion 55. That is, the assist spring 61 is arranged between the support plate 60 and the second member 31B of the fixed body 31 (see FIG. 6). The assist spring 61 is formed of a torsion coil spring having an axis extending in the width direction of the machine body, and is arranged so as to be inserted into the supported portion 55. In other words, the assist spring 61 is loosely fitted in the supported portion 55. One end of the assist spring 61 is engaged with the support plate 60. As shown in FIG. 8, the other end of the assist spring 61 is engaged with the second member 31B (fixed body 31). The biasing force of the assist spring 61 acts in a direction to rotate the movable body 32 upward. The assist spring 61 assists the operation of rotating the movable body 32 upward.

[0051] As shown in FIG. 11, the movable body 32 has a mounting bracket 62 disposed between the front and upper portion of the first wall portion 53 and the front portion of the second wall portion 54. The mounting bracket 62 has a front wall 62a, an upper wall 62b, and a rear wall 62d. The front wall 62a connects the front ends of the first wall portion 53 and the second wall portion 54. The front portion of the upper wall 62b connects the upper ends of the first wall portion 53 and the second wall portion 54. The right portion of the upper wall 62b extends rearward. The upper wall 62b also forms a valve mounting portion to which the remote control valve 24 is attached (see FIG. 4). The rear wall 62d extends downward from the rear end of the right portion of the upper wall 62b. The rear wall 62d is formed with a width narrower than the distance between the first wall portion 53 and the second wall portion 54, and is disposed closer to and fixed to the second wall portion 54. A mounting stay 64 for mounting the armrest 26L is attached to the upper portion of the rear wall 62d (see FIG. 4).

[0052] As shown in Figure 11, a support stay 65 is fixed to the lower part of the rear wall 62d. More specifically, the support stay 65 is disposed rearward of the lower part of the rear wall 62d with its plate surface facing the fuselage width direction and is fixed to the rear surface of the rear wall 62d. A support cylinder 66 is provided across the support stay 65 and the second wall portion 54. More specifically, the left part of the support cylinder 66 penetrates the support stay 65, protrudes leftward from the support stay 65, and is fixed to the support stay 65. The right end part of the support cylinder 66 penetrates the second wall portion 54 and is fixed to the second wall portion 54.

[0053] As shown in FIGS. 10 and 11 , the movable body 32 is provided with a pair of front and rear reinforcing plates 67F, 67R. The front reinforcing plate 67F has a lower end fixed to the front upper portion of the supported portion 55, extends obliquely upward and forward from the supported portion 55 along the right surface of the first wall portion 53, and extends forward at its upper portion. The front reinforcing plate 67F is fixed to the right surface of the first wall portion 53 and the front wall 62a of the mounting bracket 62. The rear reinforcing plate 67R has a lower end fixed to the rear upper portion of the supported portion 55, and has a first portion 67a extending obliquely upward and rear from the supported portion 55 along the right surface of the first wall portion 53, and a second portion 67b connecting the rear portions of the first wall portion 53 and the second wall portion 54. The first portion 67a is fixed to the right surface of the first wall portion 53 and is connected to the left portion of the second portion 67b.

[0054] 4, the detection switch 51 is attached to the rear part of the left surface of the first wall portion 53 (movable body 32). A contact plate 68 is disposed below the front part of the detection switch 51 and is fixed to the left surface of the first wall portion 53. In addition, a reinforcing portion 71 of the lever base portion 30b of the operation lock lever 30 is disposed to the left of the first wall portion 53 and in front of the detection switch 51.

[0055] As shown in FIGS. 12 and 13 , the lever base 30b has a rotating member 69, a connecting portion 70, and a reinforcing portion 71. The rotating member 69 is formed of a vertically elongated plate material with its plate surface facing the width direction of the machine body and its length extending in the up-down direction. The rotating member 69 is rotatably supported by the movable body 32 via a support shaft (second support shaft) 72. More specifically, as shown in FIG. 13 , a support boss 73 formed of a tubular member is fixed to a longitudinally intermediate portion of the right surface of the rotating member 69. The support boss 73 has an axis extending in the width direction of the machine body and is provided in the longitudinally intermediate portion of the rotating member 69. More specifically, the support boss 73 is provided above the longitudinal center of the rotating member 69. As shown in FIG. 12 , the second support shaft 72 is inserted from the right side into the support cylinder 66 of the movable body 32 and is rotatably supported by the support cylinder 66 about its axis. The left portion of the second support shaft 72 protrudes leftward from the support cylinder 66, and a support boss 73 is fitted into the portion of the second support shaft 72 protruding leftward from the support cylinder 66 and fixed with a pin, screw, or the like. Therefore, the rotating member 69 is supported by the support cylinder 66 so as to be rotatable together with the second support shaft 72 about an axis extending in the width direction of the machine body. In other words, the lever base 30b (operation lock lever 30) is supported by the movable body 32 so as to be rotatable together with the second support shaft 72 about an axis extending in the width direction of the machine body.

[0056] 12 and 13, the connecting portion 70 connects the pivoting member 69 and the base of the lever main body 30a (the rear portion of the lower portion 30d). The connecting portion 70 has a first portion 70a that extends integrally forward from the pivoting member 69, and a second portion 70b that extends leftward from the front end of the first portion 70a. The base of the lever main body 30a is fixed to the left portion of the second portion 70b.

[0057] As shown in FIGS. 12 and 13, the reinforcing portion 71 has a first portion 71a fixed to the upper end of the connecting portion 70 and a second portion 71b extending downward from the left portion of the first portion 71a. The second portion 71b of the reinforcing portion 71 is located rearward of the second portion 70b of the connecting portion 70, and the rear end of the base of the lever body 30a is fixed thereto. As shown in FIG. 4, the lower portion of the second portion 71b of the reinforcing portion 71 is located forward of the detection switch 51 (see FIG. 4) and presses the contact of the detection switch 51 when the operation lock lever 30 is in the depressed position S1. The detection switch 51 is connected to a control device for the hydraulic circuit, and when the contact of the detection switch 51 is pressed, the control device enables the hydraulic oil discharged from the hydraulic pump to be supplied to each hydraulic actuator. The contact plate 68 prevents the second portion 71b of the reinforcing portion 71 from excessively pressing the contact of the detection switch 51. As the operation lock lever 30 is rotated in the pull-up direction, the lower part of the second portion 71b of the reinforcing portion 71 moves away from the contact of the detection switch 51, and when the detection switch 51 does not detect the reinforcing portion 71, the control device makes it impossible to supply hydraulic oil discharged from the hydraulic pump to each hydraulic actuator.

[0058] As shown in FIGS. 12 and 13 , the rotating member 69 is provided with a first spring hook portion 74 and a first engagement portion 75. The first spring hook portion 74 is fixedly provided on one longitudinal end (upper portion) of the rotating member 69, and the first engagement portion 75 is fixedly provided on the other longitudinal end (lower portion) of the rotating member 69. The second support shaft 72 is located midway along the longitudinal direction of the rotating member 69. Therefore, as shown in FIGS. 14 and 15 , the first spring hook portion 74 and the first engagement portion 75 are disposed at positions sandwiching the second support shaft 72 when viewed in the axial direction of the second support shaft 72. As shown in FIG. 12 , the first spring hook portion 74 is formed by a pin having an axis extending in the width direction of the machine body, and its right portion is fixed to the rotating member 69 and protrudes leftward from the rotating member 69. As shown in FIG. 13, the first engagement portion 75 is formed by a pin having an axis extending in the width direction of the machine body (parallel to the second support shaft 72 or the third support shaft 77), and protrudes rightward from the rotating member 69.

[0059] The tension spring 47 is a spring that biases the operation lock lever 30 .

[0060] 12, 13, and 14, the switching mechanism 33 includes the above-described rotating member 69 and also includes a link 76. In this embodiment, the rotating member 69 that constitutes a part of the switching mechanism 33 is the same as the rotating member 69 that constitutes the lever base 30b, but this is not limited to this, and the rotating member 69 that constitutes the switching mechanism 33 may be separate from the rotating member 69 that constitutes the lever base 30b. Even in this case, the rotating member 69 that constitutes the switching mechanism 33 is provided to rotate integrally with the operation lock lever 30 around the second support shaft 72.

[0061] The switching mechanism 33 switches the direction of the biasing force of the tension spring 47 between a direction that pulls down the operation lock lever 30 and a direction that pulls up the operation lock lever 30 in response to a rotational operation of the operation lock lever 30. More specifically, the switching mechanism 33 switches the direction of the biasing force of the tension spring 47 between the pressed-down position S1 and the pulled-up position S2 so that the biasing force of the tension spring 47 acts in a direction that pulls down the operation lock lever 30 at the pressed-down position S1 and acts in a direction that pulls up the operation lock lever 30 at the pulled-up position S2.

[0062] As shown in Figures 12, 13, and 14, the link 76 is disposed on the right side below the rotating member 69 and is rotatably supported by the movable body 32 via a support shaft (third support shaft) 77. More specifically, the third support shaft 77 is formed of a rod having an axis extending in the width direction of the machine body, and is fixed to a longitudinal midpoint of the link 76 so as to protrude rightward. The link 76 is disposed to the left of the support plate 60 of the movable body 32. A cylindrical boss portion 78 having an axis extending in the width direction of the machine body is provided on the upper part of the support plate 60. The third support shaft 77 is inserted into the boss portion 78 of the support plate 60 so as to be rotatable about the axis extending in the width direction of the machine body, and is prevented from coming off by a washer 79 and a retaining pin.

[0063] 12, 13, and 14, the link 76 is provided with a second spring hook portion 80 and a second engagement portion 81. The second spring hook portion 80 is fixedly provided at one end (lower portion) of the link 76 in the longitudinal direction, and the second engagement portion 81 is provided at the other end (upper portion) of the link 76 in the longitudinal direction. The third support shaft 77 is fixed to a midpoint in the longitudinal direction of the link 76. Therefore, as shown in FIGS. 14 and 15, the second spring hook portion 80 and the second engagement portion 81 are disposed at positions sandwiching the third support shaft 77 when viewed in the axial direction of the third support shaft 77.

[0064] The second spring hook portion 80 is formed by a pin having an axis extending in the width direction of the machine body, and has its right portion fixed to the link 76 so as to protrude leftward from the link 76 .

[0065] As shown in FIGS. 13 and 14 , the second engagement portion 81 is formed by a groove that is long in the longitudinal direction of the link 76 and that opens at one end of the link 76. The first engagement portion 75 (pin) can be inserted into the groove 81 from the open side of the groove 81. The first engagement portion 75 is movable longitudinally within the groove 81. Therefore, the link 76 is disposed so that the first engagement portion 75 and the second engagement portion 81 engage with each other. More specifically, the link 76 is disposed abutting against the lever base 30b so that the second engagement portion 81 engages with the first engagement portion 75. Furthermore, the second engagement portion 81 of the link 76 moves and rotates around the third support shaft 77 as the first engagement portion 75 moves due to the rotation of the lever base 30b around the second support shaft 72.

[0066] In this embodiment, the first engagement portion 75 is formed by a pin parallel to the second support shaft 72 or the third support shaft 77, and the second engagement portion 81 is formed by a groove with one end open. However, this is not limited to this. The first engagement portion 75 may be formed by the groove, and the second engagement portion 81 may be formed by the pin. Also, although the second engagement portion 81 is formed by a groove that opens at the end of the link 76, the second engagement portion 81 may be formed by a hole (slot) instead of the groove. The hole refers to a groove in this embodiment in which the open side is closed (formed by a ring-shaped edge). Furthermore, when the second engagement portion 81 is formed by the pin, the first engagement portion 75 is formed by the groove or the hole (slot).

[0067] 12, the tension spring 47 is formed by a tension coil spring. The tension spring 47 is disposed between the rotating member 69 and the second portion 71b of the reinforcing portion 71, on the inner surface side (right side) of the first wall portion 53 of the movable body 32. The tension spring 47 is hung between the first spring hook portion 74 and the second spring hook portion 80. More specifically, one end of the tension spring 47 is hooked and secured to the first spring hook portion 74. The other end of the tension spring 47 is hooked and secured to the second spring hook portion 80.

[0068] 12, an insertion hole 82, through which the left end side of the second spring hook portion 80 is inserted, is formed in the lower part of the first wall portion 53 of the movable body 32. The insertion hole 82 has a lower edge formed in a substantially arc shape centered on the third support shaft 77, and an upper edge formed in a substantially straight line. Since the biasing force of the tension spring 47 acts on the second spring hook portion 80 in a direction pulling the second spring hook portion 80 upward, the upper edge of the insertion hole 82 is formed in a straight line to provide a gap between the upper edge and the second spring hook portion 80 so that the second spring hook portion 80 is not pressed against the upper edge of the insertion hole 82.

[0069] The insertion hole 82 serves to fix the link 76 (second spring hook portion 80) so that the link 76 does not rotate when the tension spring 47 is attached.

[0070] The procedure for assembling the tension spring 47 will now be described. First, the link 76 is rotatably attached to the movable body 32 via the third support shaft 77. Next, the operation lock lever 30 is attached to the movable body 32. Next, the movable body 32 is assembled to the fixed body 31 together with the assist spring 61, and the other end of the assist spring 61 is first engaged with the fixed body 31. Next, the one end of the assist spring 61 is engaged with the support plate 60 at the free angle position of the torsion coil spring. Next, the tension spring 47 is stretched and hooked onto the first spring hook portion 74 and the second spring hook portion 80. At this time, if the link 76 is not restricted in its rotational direction and is free to rotate, the rotation of the link 76 would cause the distance between the first spring hook portion 74 and the second spring hook portion 80 to become shorter than the free length of the tension spring 47, causing the tension spring 47 to come off. In this embodiment, when the tension spring 47 is hooked between the first spring hook portion 74 and the second spring hook portion 80, the second spring hook portion 80 is inserted into the insertion hole 82, and the second spring hook portion 80 is engaged (abuts) with the rear end of the insertion hole 82, thereby fixing the link 76 so that it does not rotate. As a result, when assembling the tension spring 47, there is no need for the worker to fix the link 76, making it easy to assemble the tension spring 47.

[0071] The groove, which is the second engagement portion 81 formed in the link 76, is open upward and the pin, which is the first engagement portion 75, can be inserted from the open side, so that with the link 76 assembled, the lever base 30b (rotating member 69) can be easily assembled from above.

[0072] 12, the guide plate 52 is fixed to the second support shaft 72. More specifically, the guide plate 52 is disposed to the right of the second wall portion 54 of the movable body 32 and to the left of the fixed body 31, and its upper portion is fixed to the right end of the second support shaft 72. The operation lock lever 30 is attached to the second support shaft 72 on the left side (one side) of the axial direction of the support cylinder 66, and the guide plate 52 is fixed to the second support shaft 72 on the right side (other side) of the axial direction of the support cylinder 66. Therefore, the guide plate 52 rotates integrally with the operation lock lever 30 around an axis extending in the width direction of the machine body.

[0073] Furthermore, by placing the lever base 30b inside the movable body 32, and inserting the second support shaft 72 into the support tube 66 and support boss 73 with the guide plate 52 fixed to the right end of the second support shaft 72, and then attaching the support boss 73 to the left part of the second support shaft 72, the lever base 30b and the guide plate 52 can be easily assembled to the movable body 32.

[0074] 9, a guide groove 83 is formed in the lower part of the guide plate 52, and is guided by the guide body 43 of the fixed body 31. The roller 46 of the guide body 43 is inserted into the guide groove 83. The roller 46 is relatively movable within the guide groove 83, and is rotatable within the guide groove 83.

[0075] 14 and 15 show the movable body 32 in the lowered position P1. In this state, the guide groove 83 is located below the second support shaft 72. The guide groove 83 has a first groove portion 83a at the top, a second groove portion 83b in the middle, and a third groove portion 83c at the bottom. The guide groove 83 (the first groove portion 83a, the second groove portion 83b, and the third groove portion 83c) is formed continuously. Specifically, the rear portion of the first groove portion 83a communicates with the upper portion of the second groove portion 83b, and the lower portion of the second groove portion 83b communicates with the front portion of the third groove portion 83c. The first groove portion 83a has an arc shape centered on the axis 72a of the second support shaft 72 and is formed to extend in the front-to-rear direction. The roller 46 can move relatively around the second support shaft 72 within the first groove portion 83a. The second groove portion 83b is formed to extend obliquely downward and forward from the rear portion of the first groove portion 83a. The roller 46 can move relatively within the second groove portion 83b around the first support shaft 72. Furthermore, at the upper portion of the second groove portion 83b, the roller 46 can move relatively within the second groove portion 83b around the second support shaft 72. The third groove portion 83c is formed to extend rearward from the lower portion of the second groove portion 83b. The roller 46 can move relatively within the third groove around the second support shaft 72. Furthermore, the third groove portion 83c is formed to be open downward at the rear. This allows the roller 46 to be inserted into the guide groove 83 from the open side of the third groove portion 83c.

[0076] 14 and 15, when the movable body 32 is in the lowered position P1 and the operation lock lever 30 is in the pressed-down position S1, the roller 46 is located at the front end of the first groove 83a. When the roller 46 is located at the front end of the first groove 83a, the roller 46 abuts against the lower edge (first restricting portion) 83d of the first groove 83a, restricting the upward rotation of the guide plate 52 about the first support shaft 39. This restricts the movable body 32 from rotating in the upward direction about the first support shaft 39. Furthermore, the operation lock lever 30 and the guide plate 52 can rotate in the direction that pulls up the operation lock lever 30. In other words, the first groove 83a restricts the movable body 32, which is in the lowered position P1, from rotating in the upward direction, while allowing the operation lock lever 30 to rotate in the upward direction.

[0077] Furthermore, when the operation lock lever 30 is in the pressed-down position S1, the front edge (second restricting portion) 83e of the first groove portion 83a abuts against the roller 46, thereby restricting the guide plate 52 from rotating backward around the second support shaft 72. This restricts the operation lock lever 30 from rotating in the pressing-down direction around the second support shaft 72 from the pressed-down position S1.

[0078] 16 and 17, where the operation lock lever 30 is pulled up from the depressed position S1 to rotate the guide plate 52 around the second support shaft 72, the roller 46 is located at the rear end of the first groove 83a. When the roller 46 is located at the rear end of the first groove 83a, the roller 46 can move relatively within the second groove 83b, and the restriction on the upward rotation of the guide plate 52 around the first support shaft 39 caused by the roller 46 coming into contact with the first restricting portion 83d is released. In other words, the second groove 83b allows the movable body 32 to rotate when the operation lock lever 30 is operated.

[0079] 20 and 21, in which the operation lock lever 30 is further raised from the position shown in FIGS. 16 and 17 to rotate the movable body 32 around the first support shaft 39, the roller 46 is positioned at the front end of the third groove 83c. When the roller 46 is positioned at the front end of the third groove 83c, as shown in FIG. 20, the abutment plate 59 abuts against the position restricting member 42, restricting the rotation of the movable body 32 in the lifting direction. That is, the movable body 32 is at the lifted position P2. In this state, the roller 46 can move within the third groove 83c relative to the movable body 32 around the second support shaft 72. That is, the third groove 83c allows the operation lock lever 30 to rotate around the second support shaft 72 with respect to the movable body 32 at the lifted position P2. 20 to the raised position S2 shown in FIG. 22, the roller 46 is positioned at the rear end of the third groove 83c. At this position, the roller 46 abuts against the upper edge (locking portion) 83f of the third groove 83c, restricting downward rotation of the guide plate 52 about the first support shaft 39. This restricts downward rotation of the movable body 32 about the first support shaft 39. In other words, the third groove 83c has the locking portion 83f that restricts downward rotation of the movable body 32 from the raised position P2 when the operation lock lever 30 is in the raised position S2.

[0080] Next, the operation of the switching mechanism 33 will be described with reference to FIGS.

[0081] 14, when the movable body 32 is in the lowered position P1 and the operation lock lever 30 is in the pressed-down position S1, as shown in Fig. 15, the center axis 84 of the tension spring 47 is located in front of the second support shaft 72, and the biasing force of the tension spring 47 acts in a direction to pull down the operation lock lever 30. When the operation lock lever 30 is in the pressed-down position S1, the roller 46 is located at the front end of the first groove portion 83a, and rotation of the operation lock lever 30 in the pressed-down direction is restricted, so the biasing force of the tension spring 47 holds the operation lock lever 30 in the pressed-down position S1.

[0082] When the operation lock lever 30 is pulled up around the second support shaft 72 from the depressed position S1 shown in FIG. 14 , the movable body 32 remains in the depressed position P1, and the roller 46 moves relatively rearward within the first groove 83a, causing the operation lock lever 30 and the guide plate 52 to rotate in the upward direction around the second support shaft 72 (see FIG. 16 ). At this time, the rotating member 69 rotates clockwise together with the operation lock lever 30, causing the first spring hook portion 74 to move rearward and the first engagement portion 75 to move forward. Then, as the first engagement portion 75 moves forward, the second engagement portion 81 moves forward, causing the link 76 to rotate counterclockwise around the third support shaft 77, and causing the second spring hook portion 80 to move rearward. In other words, the first spring hook portion 74 and the second spring hook portion 80 move to the same side. When the first spring hook portion 74 and the second spring hook portion 80 move rearward, the central axis 84 of the tension spring 47 moves in a direction approaching the axis 72 a of the second support shaft 72 .

[0083] 16 and 17, when the roller 46 moves to the rear end of the first groove portion 83a, the movable body 32 is allowed to rotate in the lifting direction about the first support shaft 39. Furthermore, when the roller 46 is located at the rear end of the first groove portion 83a, the first spring hook portion 74, the second support shaft 72, and the third support shaft 77 are aligned in a substantially straight line.

[0084] 16, the roller 46 moves relatively downward along the upper portion of the second groove portion 83b (see FIGS. 18 and 19). When the roller 46 moves relatively along the upper portion of the second groove portion 83b, a force in the upward direction is transmitted from the operation lock lever 30 to the movable body 32 via the second support shaft 72 and the support cylinder 66, causing the movable body 32 to rotate in the upward direction about the first support shaft 39, and also causing the operation lock lever 30 and the guide plate 52 to rotate in the upward direction about the second support shaft 72. When the operation lock lever 30 rotates in the lifting direction around the second support shaft 72, the first spring hook portion 74 and the second spring hook portion 80 move rearward, similar to the operation described above, and as shown in Figure 19, the central axis 84 of the tension spring 47 moves rearward away from the axis 72a of the second support shaft 72, and the biasing force of the tension spring 47 switches to a direction that lifts the operation lock lever 30.

[0085] When the operation lock lever 30 is further pulled up from the state shown in Figure 18 and the roller 46 moves relatively from the middle to the lower end of the second groove portion 83b, the movable body 32, operation lock lever 30, guide plate 52, rotating member 69 and link 76 rotate together in the upward direction around the first support shaft 39.

[0086] 20 and 21, when roller 46 moves relative to the lower end of second groove portion 83b, movable body 32 is placed in raised position P2, and contact plate 59 comes into contact with position restriction member 42, restricting rotation of movable body 32 in the raised direction. When movable body 32 is operated to raised position P2 by operation lock lever 30, the position of operation lock lever 30 is not raised position S2 but raised operation position S3, which is located just before raised position S2. When operation lock lever 30 is in raised operation position S3, roller 46 is positioned at the front end of third groove portion 83c (lower end of second groove portion 83b), as shown in FIG.

[0087] When the operation lock lever 30 is further pulled up from the raised operation position S3 toward the movable body 32 which is in the raised position P2, the guide plate 52 rotates forward around the second support shaft 72, and similar to the operation described above, the first spring hook portion 74 and the second spring hook portion 80 move rearward, and as shown in Figure 23, the central axis 84 of the tension spring 47 moves further rearward away from the axis 72a of the second support shaft 72, further strengthening the biasing force of the tension spring 47 in the direction of pulling up the operation lock lever 30.

[0088] When the operation lock lever 30 is pushed down from the raised position S2 to the depressed position S1, the biasing force of the tension spring 47 is switched by the reverse operation of the above operation.

[0089] Furthermore, to put it another way, the switching operation of the biasing force of the tension spring 47 is as follows: if the rear side, which is the side to which the first spring hook portion 74 moves when the operation lock lever 30 is pulled up and operated, is defined as the first side, and the front side, which is opposite the first side, is defined as the second side (see FIG. 15), when the operation lock lever 30 is pulled up and the rotating member 69 rotates around the second support shaft 72, the first spring hook portion 74 moves to the first side (rear side), and the first engagement portion 75 and the second engagement portion 81 move to the second side (front side), and the second spring hook portion 80 moves to the first side (rear side); and when the operation lock lever 30 is pushed down and the rotating member 69 rotates around the second support shaft 72, the first spring hook portion 74 moves to the second side (front side), and the first engagement portion 75 and the second engagement portion 81 move to the first side (rear side), and the second spring hook portion 80 moves to the second side. As a result, the central axis 84 of the tension spring 47 moves to the first side (rear side) of the second support shaft 72 or the second side (front side) of the second support shaft 72, switching the direction of the biasing force of the tension spring 47. In other words, as the operation lock lever 30 is operated, the direction of the biasing force of the tension spring 47 acting on the operation lock lever 30 switches between a direction that pulls the operation lock lever 30 down and a direction that pulls the operation lock lever 30 up.

[0090] Furthermore, when the operation lock lever 30 is in the raised position S2, the roller 46 is located at the rear end of the third groove portion 83c, thereby restricting rotation in the raised direction of the operation lock lever 30. Therefore, when in the raised position S2, the operation lock lever 30 is held in the raised position S2 by the biasing force of the tension spring 47.

[0091] As described above, when the first engagement portion 75 is moved by operating the operation lock lever 30, the link 76 rotates, causing the second spring hook portion 80 to move to the side to which the first spring hook portion 74 has moved. This allows the central axis 84 of the tension spring 47 to be sufficiently separated from the second support shaft 72 at the pushed-down position S1 and the pulled-up position S2, and the biasing force (holding force) of the tension spring 47 on the operation lock lever 30 can be applied even when the rotation angle of the movable body 32 is small.

[0092] A preferred embodiment of the present invention provides a lever device 27 and a work implement 1 as described in the following items.

[0093] (Item 1) The lever 30 includes a fixed body 31, a movable body 32 rotatably supported on the fixed body 31 via a first support shaft 39, a lever 30 for rotating the movable body 32 around the first support shaft 39, the lever 30 being rotatably supported on a second support shaft 72 provided on the movable body 32 at a pressed-down position S1 and a pulled-up position S2 rotated upward from the pressed-down position S1, a tension spring 47 for biasing the lever 30, and a switching mechanism 33 for switching the direction of the biasing force of the tension spring 47 between the pressed-down position S1 and the pulled-up position S2 so that the biasing force of the tension spring 47 acts in a direction to pull down the lever 30 at the pressed-down position S1 and acts in a direction to pull up the lever 30 at the pulled-up position S2, the switching mechanism 33 being a rotating member 69 that rotates integrally with the lever 30 around the second support shaft 72, and a link 76 rotatably supported on the movable body 32 via a third support shaft 77, the link 76 having a second spring hook 80 and a second engaging portion 81 arranged at positions sandwiching the third support shaft 77 when viewed from the axial direction of the third support shaft 77, wherein the tension spring 47 is hung between the first spring hook 74 and the second spring hook 80, the link 76 is arranged so that the first engaging portion 75 and the second engaging portion 81 engage with each other, and the second engaging portion 81 moves and rotates about the third support shaft 77 as the first engaging portion 75 moves due to the rotation of the rotating member 69 about the second support shaft 72, thereby moving the second spring hook 80 to the same side as the movement of the first spring hook 74.

[0094] According to the lever device 27 relating to this item 1, the rotation of the link 76 accompanying the movement of the first engagement portion 75 by operating the lever 30 causes the second spring hook portion 80 to move to the side to which the first spring hook portion 74 has moved, so that the central axis of the tension spring 47 can be moved to an appropriate position away from the center of the second support shaft 72 at the pushed-down position S1 and the pulled-up position S2, and the biasing force of the tension spring 47 on the lever 30 can be applied even when the rotation angle of the movable body 32 is small.

[0095] (Item 2) Item 1. The lever device 27 according to item 1, wherein one of the first engagement portion 75 and the second engagement portion 81 is formed by a pin parallel to the second support shaft 72 or the third support shaft 77, and the other of the first engagement portion 75 and the second engagement portion 81 is formed by a groove or a hole into which the pin can be inserted.

[0096] According to the lever device 27 relating to item 2, the rotation of the link 76 accompanying the movement of the first engagement portion 75 by operating the lever 30 allows the second spring hook portion 80 to move to the side to which the first spring hook portion 74 has moved.

[0097] (Item 3) When the lever 30 is pulled up and operated, the side to which the first spring hook portion 74 moves is defined as a first side, and the side opposite to the first side is defined as a second side. When the lever 30 is pulled up and the rotating member 69 rotates around the second support shaft 72, the first spring hook portion 74 moves to the first side, and the first engaging portion 75 and the second engaging portion 81 move to the second side, and the second spring hook portion 80 moves to the first side, and the lever 30 is pushed down to move the rotating member 69. 9 rotates around the second support shaft 72, the first spring hook portion 74 moves to the second side, and the first engagement portion 75 and the second engagement portion 30 move to the first side, and the second spring hook portion 80 moves to the second side, whereby the direction of the biasing force of the tension spring 47 acting on the lever 30 switches between a direction that pulls the lever 30 down and a direction that pulls the lever 30 up as the lever 30 is operated.

[0098] The lever device 27 according to item 3 also allows the central axis of the tension spring 47 to be appropriately spaced from the center of the second support shaft 72 at the depressed position S1 and the raised position S2, and the biasing force of the tension spring 47 on the lever 30 can be applied even when the rotation angle of the movable body 32 is small.

[0099] (Item 4) A lever device (27) according to any one of items (1) to (3), wherein the movable body (32) is rotatable between a lowered position (P1) and a raised position (P2) rotated upward from the lowered position (P1) around the first support shaft (39), the depressed position (S1) of the lever (30) corresponds to the lowered position (P1) of the movable body (32), the lever (30) is operable to a raised operation position (S3) which is the position when the movable body (32) is operated to the raised position (P2), and the raised position (S2) of the lever (30) is a position where the lever (30) is further raised from the raised operation position (S3) relative to the movable body (32) which is at the raised position (P2).

[0100] According to the lever device 27 relating to this item 4, the amount of movement of the first spring hook portion 74 and the second spring hook portion 80 in the lifting direction of the lever 30 can be increased.

[0101] (Item 5) Item 4. A lever device 27 according to item 4, comprising: a guide body 43 provided on the fixed body 31; and a guide plate 52 having a guide groove 83 into which the guide body 43 fits and rotating integrally with the lever 30 around the second support shaft 72, wherein the guide groove 83 has: a first groove portion 83a that restricts the movable body 32 at the lowered position P1 from rotating in the upward direction and allows the lever 30 to rotate in the pulled-up direction; a second groove portion 83b that allows the movable body 32 to rotate by operation of the lever 30; and a third groove portion 83c that restricts the movable body 32 at the raised position P2 from rotating in the upward direction and allows the lever 30 to rotate about the second support shaft 72, and the third groove portion 83c has a locking portion 83f that restricts the movable body 32 from rotating in the downward direction from the raised position P2 when the lever 30 is at the raised position S2.

[0102] According to the lever device 27 relating to item 5, the biasing force of the tension spring 47 on the lever 30 can be applied even when the rotation angle of the movable body 32 is small, and inadvertent downward rotation of the movable body 32 can be restricted.

[0103] (Item 6) Item 5. The lever device 27 according to item 5, wherein the movable body 32 has a support cylinder 66 that supports the second support shaft 72 so as to be rotatable about its axis, the lever 30 is attached to the second support shaft 72 on one side of the support cylinder 66 in the axial direction, and the guide plate 52 is fixed to the second support shaft 72 on the other side of the support cylinder 66 in the axial direction.

[0104] According to the lever device 27 related to this item 6, the guide plate 52 can be easily assembled to the movable body 32.

[0105] (Item 7) The work machine 1 of this embodiment is equipped with a lever device 27 described in any one of items 1 to 6.

[0106] (Item 8) 8. The work implement 1 according to item 7, wherein the lever 30 is an operation lock lever that switches an actuator provided in the work implement 1 between an operable state and an inoperable state.

[0107] According to the work machine 1 relating to this item 8, even when the rotation angle of the movable body 32 is small, the biasing force of the tension spring 47 can be applied to the lock lever.

[0108] Although one embodiment of the present invention has been described above, the embodiment disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0109] 1 Work equipment 27 Lever device 30 Lever (operation lock lever) 31 Fixed body 32 Movable body 33 Switching mechanism 39 1st spindle 43 Guide body 47 Tension spring 52 Guide plate 66 Support tube 69 Rotating member 72 2nd support shaft 74 First spring holder 75 First engagement part 76 Links 77 3rd spindle 80 Second spring hook 81 second engagement portion 83 Guide groove 83a First groove 83b 2nd groove 83c 3rd groove 83f Locking part S1 Pressed down position S2 Raised position S3 Raise operation position

Claims

1. A fixed body; a movable body rotatably supported by the fixed body via a first support shaft; a lever for rotating the movable body around the first support shaft, the lever being rotatably supported on a second support shaft provided on the movable body between a pressed-down position and a pulled-up position rotated upward from the pressed-down position; a tension spring that biases the lever; a switching mechanism that switches the direction of the biasing force of the tension spring between the pressed-down position and the pulled-up position so that the biasing force of the tension spring acts in a direction that pulls down the lever at the pressed-down position and acts in a direction that pulls up the lever at the pulled-up position, The switching mechanism is a rotating member that rotates integrally with the lever around the second support shaft, the rotating member having a first spring hook portion and a first engagement portion disposed at positions sandwiching the second support shaft when viewed in the axial direction of the second support shaft; a link that is rotatably supported by the movable body via a third support shaft, the link having a second spring hook portion and a second engagement portion that are disposed at positions sandwiching the third support shaft when viewed in the axial direction of the third support shaft; the tension spring is hung between the first spring hook portion and the second spring hook portion, The link is arranged so that the first engagement portion and the second engagement portion engage with each other, and the second engagement portion moves and rotates around the third support axis in conjunction with the movement of the first engagement portion due to the rotation of the rotating member around the second support axis, thereby moving the second spring hook portion to the same side as the first spring hook portion.

2. one of the first engaging portion and the second engaging portion is formed by a pin parallel to the second support shaft or the third support shaft, The lever device according to claim 1 , wherein the other of the first engaging portion and the second engaging portion is formed by a groove or a hole into which the pin can be inserted.

3. When the lever is pulled up and operated, the side to which the first spring hook portion moves is defined as a first side, and the side opposite to the first side is defined as a second side. when the lever is pulled up and the rotating member is rotated around the second support shaft, the first spring hook portion moves to the first side, and the first engaging portion and the second engaging portion move to the second side, and the second spring hook portion moves to the first side, When the lever is pushed down and the rotating member is rotated around the second support shaft, the first spring hook portion moves to the second side, and the first engagement portion and the second engagement portion move to the first side, and the second spring hook portion moves to the second side, 2. The lever device according to claim 1, wherein the direction of the biasing force of the tension spring acting on the lever switches between a direction that pulls the lever down and a direction that pulls the lever up as the lever is operated.

4. the movable body is rotatable between a lowered position and a raised position rotated upward from the lowered position around the first support shaft, the depressed position of the lever corresponds to the lowered position of the movable body, the lever can be operated to a raising operation position, which is a position when the movable body is operated to the raising position, 2. The lever device according to claim 1, wherein the raised position of the lever is a position where the lever is further raised from the raising operation position relative to the movable body that is in the raised position.

5. a guide body provided on the fixed body; a guide plate having a guide groove into which the guide body is fitted and rotating integrally with the lever around the second support shaft; Equipped with The guide groove is a first groove portion that restricts the movable body in the lowered position from rotating in the raising direction and allows the lever to rotate in the pulling-up direction; a second groove portion that allows the movable body to rotate by operating the lever; a third groove portion that restricts rotation of the movable body in the raising direction when the movable body is in the raised position and allows rotation of the lever about the second support shaft, 5. The lever device according to claim 4, wherein the third groove portion has a locking portion that prevents the movable body from rotating in a lowering direction from the raised position when the lever is in the raised position.

6. the movable body has a support cylinder that supports the second support shaft so as to be rotatable about its axis, the lever is attached to the second support shaft at one side of the support cylinder in the axial direction; 6. The lever device according to claim 5, wherein the guide plate is fixed to the second support shaft on the other side of the support cylinder in the axial direction.

7. A work machine comprising the lever device according to any one of claims 1 to 6.

8. 8. The work machine according to claim 7, wherein the lever is an operation lock lever that switches an actuator provided in the work machine between an operable state and an inoperable state.

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