JP2018188919A - Front loader attaching/detaching structure, front loader, and operation vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a front loader attaching/detaching structure, front loader, and operation vehicle, capable of making it easy to perform attaching/detaching work to/from a vehicle body.SOLUTION: A front loader attaching/detaching structure comprises: a thumb 230 that is supported on a sub frame 210 for supporting a boom 300 so as to be movable between an engagement position at which the thumb engages with a main frame 100 provided on a vehicle body 1 and a release position at which engagement with the main frame 100 is released and is energized in a release direction from the engagement position to the release position; and a lock bar 240 supported on the sub frame 210 so as to be movable between a restriction position at which the thumb 230's movement from the engagement position to the release position is restricted and a restriction release position at which the thumb 230's movement to the release position is permitted.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a front loader attaching / detaching structure mounted on a work vehicle such as a tractor, a front loader, and a work vehicle technology.

  Conventionally, a technique for attaching / detaching a front loader mounted on a work vehicle such as a tractor has been publicly known. For example, as described in Patent Document 1.

  Patent Document 1 describes a tractor including a front loader for loading earth and sand. The front loader is attached to the tractor body via a work support attached to the main frame.

  Such a front loader is removed from the vehicle body when not needed, and is attached to the vehicle body when necessary. For this reason, a front loader that can be easily attached to and detached from the vehicle body is required.

JP 2011-126325 A

  SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and a problem to be solved is to provide a front loader attaching / detaching structure, a front loader, and a work vehicle that can facilitate attaching / detaching work to / from a vehicle body. It is to be.

  The problem to be solved by the present invention is as described above. Next, means for solving the problem will be described.

  That is, according to the first aspect, the sub-frame that supports the boom moves between an engagement position that engages with the main frame provided on the vehicle body and a release position that releases the engagement with the main frame. The engagement member that is supported in a movable manner and is biased in the release direction from the engagement position toward the release position, and the engagement member moves in the release direction from the engagement position to the subframe. A restriction member that is supported so as to be movable between a restriction position that restricts the movement of the engagement member and a restriction release position that permits the engagement member to move to the release position.

  According to a second aspect of the present invention, the restricting member is formed to abut against the engaging member located at the engaging position at the restricting position and restrict movement of the engaging member in the releasing direction. It is what.

  According to a third aspect of the present invention, the engagement member is formed on the subframe so as to be swingable between the engagement position and the release position.

  According to a fourth aspect of the present invention, the restriction member is formed on the sub-frame so as to be swingable between the restriction position and the restriction release position.

  The engagement member may be pressed by the main frame and moved from the release position toward the engagement position when the main frame is relatively moved so as to be close to the sub frame. It is formed as follows.

  In claim 6, the restriction member is biased in a restriction direction from the restriction release position toward the restriction position, and when the engagement member moves from the release position toward the engagement position, Following the engagement member, it is formed so as to move from the restriction release position to the restriction direction.

  According to a seventh aspect of the present invention, there is provided a holding mechanism that holds the restriction member at the restriction position and the restriction release position.

  The holding mechanism that holds the restriction member at the restriction position and the restriction release position is provided, and the holding mechanism is at an intermediate position between the restriction position and the restriction release position. A detent mechanism for locking the member so as not to move in the restriction direction, and the engagement member moves in the release direction in a state where the restriction member is locked at the intermediate position by the detent mechanism. The restriction member is pressed and moved to the restriction release position.

  According to a ninth aspect of the present invention, the detent mechanism is provided on the restriction member that is urged so as to come into contact with the outer peripheral portion of the restriction member, and is latched by the lock part at the intermediate position. And a locked portion.

  According to a tenth aspect of the present invention, when the restriction member moves from the restriction release position toward the restriction direction, the locking portion is prevented from being locked to the locked portion at the intermediate position. A control member is provided.

  According to an eleventh aspect, the control member presses the locking portion against the urging force received by the locking portion at the intermediate position, so that the locking portion is engaged with the locked portion. It is formed so as to avoid being stopped.

  In the twelfth aspect of the present invention, the engagement member is formed on the subframe so as to be swingable between the engagement position and the release position. The frame is formed so as to be swingable between the restriction position and the restriction release position, and the swing shaft of the engagement member is parallel to the swing shaft of the restriction member. The contact portion of the restricting member with the engaging member is formed in an arc shape centered on the swing axis of the restricting member when viewed in the swing axis direction of the restricting member, The contact portion of the engagement member with the restriction member has a radius of curvature that is substantially the same as the curvature radius of the contact portion of the restriction member with the engagement member as viewed in the swing axis direction of the engagement member. It is formed in an arc shape.

  According to a thirteenth aspect of the present invention, the restricting member is formed such that, in the restricting position, a pressing force received from the engaging member located at the engaging position is directed toward the swing center of the restricting member. is there.

  In Claim 14, the operation tool for moving the said limitation member is comprised.

  According to a fifteenth aspect, the detachable structure according to any one of the first to fourteenth aspects is provided.

  A sixteenth aspect includes the front loader according to the fifteenth aspect.

  As effects of the present invention, the following effects can be obtained.

  According to the first aspect, it is possible to facilitate the attaching and detaching work to the vehicle body. Specifically, the engagement member can be easily moved to the release position by simply moving the restriction member to the restriction release position, and the engagement between the engagement member and the main frame can be released.

  According to the second aspect, the movement of the engaging member in the releasing direction can be restricted with a simple structure.

  According to the third aspect, the engagement member can be engaged with the main frame with a simple structure, and the engagement between the engagement member and the main frame can be released.

  According to the fourth aspect of the present invention, it is possible to restrict the movement of the engagement member from the engagement position in the release direction and to release the restriction on the movement of the engagement member with a simple structure.

  According to the fifth aspect of the present invention, the engagement member can be easily engaged with the main frame by bringing the vehicle body close to the sub-frame removed from the vehicle body (main frame).

  According to a sixth aspect of the present invention, when the engaging member returns to the engaging position and is engaged with the main frame, the restricting member can be returned to the restricting position, and as a result, the restricting member moves the engaging member in the releasing direction. Can be regulated.

  In the seventh aspect, the engaging member can be held at the engaging position by holding the restricting member at the restricting position. Further, by holding the restriction member at the restriction release position, the engagement member can be held at the release position.

  In Claim 8, it can suppress that an engaging member moves to a releasing position vigorously.

  According to the ninth aspect of the present invention, the locking member is locked to the locked portion, so that the regulating member can be held at the intermediate position.

  In claim 10, when the restriction member is moved from the restriction position toward the restriction release position, the restriction member can be held at the intermediate position, and the restriction member is directed from the restriction release position toward the restriction position. In the case of movement, the restricting member can be moved to the restricting position without being held at the intermediate position.

  According to the eleventh aspect, when the restriction member is moved from the restriction release position to the restriction position with a simple structure, the restriction member can be moved to the restriction position without being held at the intermediate position.

  In the twelfth aspect, the restricting member can be swung without being obstructed by the engaging member.

  According to the thirteenth aspect, when the restricting member restricts the swinging of the engaging member, it is possible to prevent the restricting member from swinging due to the pressing force received from the engaging member.

  In the fourteenth aspect, the restricting member can be easily moved using the operation tool.

  According to the fifteenth aspect, it is possible to provide a front loader capable of facilitating the attachment / detachment work to / from the vehicle body.

  According to the sixteenth aspect, it is possible to provide a work vehicle capable of facilitating the work of attaching and detaching the front loader to the vehicle body.

The side view which showed the whole structure of the tractor with which the front loader which concerns on one Embodiment of this invention was mounted | worn. The side view of the front loader attached to the body frame etc. The left view of the upper part of a main frame. The upper right perspective view of a sub-frame unit. The upper left perspective view of a sub-frame unit. The principal part enlarged view of FIG. The left view which showed the attachment / detachment structure of the main frame and the sub-frame unit. (A) The left view which showed a part of sub-frame unit of the state hold | maintained at the main frame. (B) A partially enlarged view of FIG. (A) The left view which showed a part of sub-frame unit in the middle of removing from a main frame. (B) A partially enlarged view of FIG. (A) The left view which showed a part of sub-frame unit in the middle of removing from a main frame. (B) A partially enlarged view of FIG. (A) The left view which showed a part of sub-frame unit of the state removed from the main frame. (B) A partially enlarged view of FIG. The left view which showed a part of main frame and sub-frame unit before attaching a sub-frame unit to a main frame. The left view which showed a part of main frame in the middle of attaching a sub-frame unit to a main frame, and a sub-frame unit. (A) The left view which showed a part of sub-frame unit in the middle of mounting | wearing to a main frame. (B) A partially enlarged view of FIG. (A) The left view which showed a part of sub-frame unit in the middle of mounting | wearing to a main frame. (B) A partially enlarged view of FIG. (A) The left view which showed a part of sub-frame unit in the middle of mounting | wearing to a main frame. (B) A partially enlarged view of FIG. The left view which showed a part of main frame in the middle of attaching a sub-frame unit to a main frame, and a sub-frame unit. The left view which showed a part of main frame and sub-frame unit of the state which attached the sub-frame unit to the main frame. The left view which showed a part of sub-frame unit which concerns on another example.

  In the following, the directions indicated by arrow U, arrow D, arrow F, arrow B, arrow L and arrow R in the figure are defined as upward, downward, forward, backward, leftward and rightward, respectively. To explain.

  First, the whole structure of the vehicle body 1 of the tractor provided with the front loader 20 which concerns on 1st embodiment of this invention is demonstrated using FIG.1 and FIG.2.

  The tractor mainly includes a body frame 2, an engine 3, a transmission case 4, front wheels 5, rear wheels 6, a hood 7, an SCR 8, a muffler 9, a cabin 10, a steering wheel 11, and a front loader 20.

  The body frame 2 is a frame-like member formed by appropriately combining a plurality of plate materials. The body frame 2 is formed in a substantially rectangular shape in plan view. The body frame 2 is disposed at the front portion of the vehicle body 1 with its longitudinal direction facing the front-rear direction. An engine 3 is fixed to the rear part of the body frame 2. A transmission case 4 is fixed to the rear portion of the engine 3. The front part of the body frame 2 is supported by a pair of left and right front wheels 5 via a front axle mechanism (not shown). The rear part of the transmission case 4 is supported by a pair of left and right rear wheels 6 via a rear axle mechanism (not shown). The engine 3 is covered with a hood 7.

  An SCR (Selective Catalytic Reduction) 8 for purifying exhaust gas of the engine 3 is disposed on the right side of the bonnet 7. A muffler 9 that discharges the exhaust gas of the engine 3 is disposed above the SCR 8. The SCR 8 and the muffler 9 are fixed to the transmission case 4.

  The power of the engine 3 can be transmitted to the front wheels 5 through the front axle mechanism after being shifted by a transmission (not shown) housed in the transmission case 4, and the rear wheels 6 through the rear axle mechanism. It can be transmitted to. The front wheels 5 and the rear wheels 6 are rotationally driven by the power of the engine 3 so that the tractor can travel.

  A cabin 10 is provided behind the engine 3. In the cabin 10, a living space in which the driver gets on is formed. In the living space, a steering wheel 11 for adjusting the turning angle of the front wheel 5, various operating tools (not shown), a seat (not shown) for a driver to sit, and the like are arranged.

  A front loader 20 is attached to the front portion of the vehicle body 1. The front loader 20 mainly includes a pair of left and right main frames 100, a pair of left and right subframe units 200, a pair of left and right booms 300, and a bucket 400.

  The main frame 100 is fixed to the left and right sides of the vehicle body 1 (the body frame 2 and the transmission case 4). The subframe unit 200 is detachably supported on the top of each main frame 100. The boom 300 is rotatably supported by each subframe unit 200. The boom 300 is disposed so as to extend from the upper part of the main frame 100 toward the front lower side. Bucket 400 is rotatably connected to the front end of boom 300. The boom 300 can be rotated with respect to the subframe unit 200 by expanding and contracting the boom cylinder 300a. The bucket 400 can be rotated with respect to the boom 300 by expanding and contracting the bucket cylinder 400a. In this manner, earth and sand can be transported while appropriately rotating the boom 300 and the bucket 400.

  Next, a detailed configuration of the main frame 100 will be described with reference to FIGS. 2, 3, and 7. The pair of left and right main frames 100 are disposed at symmetrical positions.

  The main frame 100 shown in FIG. 2 supports the sub-frame unit 200 that supports the boom 300. In other words, the main frame 100 supports the boom 300 via the subframe unit 200. The main frame 100 mainly includes a fixed frame 110, a connection frame 120, and a support frame 130.

  A fixed frame 110 shown in FIG. 2 is a portion fixed to the vehicle body 1. The fixed frame 110 is formed in a plate shape whose plate surface is directed in the left-right direction. The fixed frame 110 is fixed to the body frame 2 by bolts or the like.

  The connecting frame 120 shown in FIG. 2 connects the fixed frame 110 and a support frame 130 described later. The connection frame 120 is formed in a substantially cylindrical shape whose axis is directed in the left-right direction. One end (left end) of the connection frame 120 is inserted into the fixed frame 110 and is appropriately fixed to the fixed frame 110 by welding.

  A support frame 130 illustrated in FIG. 2 is a portion that supports the subframe unit 200. The support frame 130 is formed in a plate shape whose plate surface is directed in the left-right direction. The support frame 130 is disposed with the longitudinal direction thereof directed upward and downward. The connection frame 120 is inserted under the support frame 130, and the support frame 130 and the connection frame 120 are fixed by welding. A main frame side pin 131, a main frame side hook 132, and a main frame side guide surface 133 are formed on the support frame 130.

  The main frame side pin 131 shown in FIGS. 3 and 7 is a portion that is held by a subframe unit 200 (more specifically, a subframe side hook 222 of the guide plate 220) described later. The main frame side pin 131 is formed at the front upper end of the support frame 130 in a columnar shape with the axis line in the left-right direction. The main frame side pin 131 is formed so as to protrude from the support frame 130 to the left and right.

  The main frame side hook 132 shown in FIGS. 3 and 7 is a portion that holds a subframe unit 200 (more specifically, a subframe side pin 211 of the subframe 210) described later. The main frame side hook 132 is formed in a substantially U shape with the front opened in a side view, and can support a subframe side pin 211 described later from below. The main frame side hook 132 is formed at the rear upper end portion of the support frame 130 and above the main frame side pin 131.

  The main frame side guide surface 133 shown in FIGS. 3 and 7 is provided when the subframe unit 200 (described later) is attached to the main frame 100, and more specifically, the subframe unit 200 (more specifically, the subframe side pin 211 of the subframe 210 ) To the mounting position. The main frame side guide surface 133 is formed on the upper end portion of the support frame 130 in a planar shape with the surface facing substantially upward. More specifically, the main frame-side guide surface 133 is formed between the main frame-side pin 131 and the main frame-side hook 132 in the shape of a front-declining slope whose height in the vertical direction decreases toward the front. . The main frame side guide surface 133 is not continuously formed up to the main frame side pin 131, and a recess 133 a is formed between the main frame side pin 131 and the main frame side guide surface 133. By forming the recess 133a, it is possible to prevent the main frame side pin 131 from being deformed or damaged due to a contact impact or the like during attachment / detachment.

  Next, a detailed configuration of the subframe unit 200 will be described with reference to FIGS. 4 to 8. The pair of left and right subframe units 200 are formed symmetrically with each other. In FIGS. 4 to 8 (and FIGS. 9 to 19 to be described later), The right subframe unit 200 is illustrated. In the following description, the right subframe unit 200 is described unless otherwise specified, and the description of the left subframe unit 200 is omitted. 4 to 8 show a state (attached state) in which the subframe unit 200 is attached to the main frame 100, and the following description is based on this attached state.

  The subframe unit 200 is a portion provided between the main frame 100 and the boom 300. The subframe unit 200 supports the boom 300 in a rotatable manner at the upper part (see FIG. 2). The subframe unit 200 includes a subframe 210, a guide plate 220, a thumb 230, a lock bar 240, a control plate 250, a detent pin 260, and an operation tool 270.

  The subframe 210 is a part constituting the right part and the left part of the subframe unit 200. The subframe 210 is formed in a plate shape with the plate surface facing in the left-right direction. The sub-frame 210 is disposed with the longitudinal direction thereof directed upward and downward. A pair of subframes 210 are provided on the left and right, and are connected to each other by an appropriate member. In FIGS. 5 to 8 (and FIGS. 9 to 20 described later), the left subframe 210 is not shown for convenience of explanation. In the subframe 210, a subframe side pin 211 and a restriction hole 212 are formed.

  The sub-frame side pins 211 shown in FIGS. 4, 5, and 7 are portions that are held by the main frame-side hooks 132 (see FIG. 3) of the support frame 130. The subframe side pin 211 is formed in a cylindrical shape. The subframe-side pin 211 is fixed to the rear lower part of the subframe 210 with the axis line directed in the left-right direction. The subframe-side pin 211 is provided between the pair of left and right subframes 210 so as to connect the pair of left and right subframes 210.

  The restriction hole 212 shown in FIGS. 4 to 8 is for restricting the operating range of the operation tool 270 described later. The restriction hole 212 is formed so as to penetrate the subframe 210 in the left-right direction. The restriction hole 212 is formed in a partial annular shape with a central angle of about 30 ° centered on a rocking center (rocking shaft 241) of a lock bar 240, which will be described later, in a side view. The restriction hole 212 is formed above the swing shaft 241.

  The guide plate 220 shown in FIGS. 4 to 8 guides the main frame 100 to the mounting position when the sub-frame unit 200 is mounted on the main frame 100, and holds the main frame 100 at the mounting position. The guide plate 220 is formed in a plate shape whose plate surface is directed in the left-right direction. A pair of guide plates 220 are provided on the left and right. Each guide plate 220 is fixed inside the pair of left and right subframes 210, respectively. 5 to 8 (and FIGS. 9 to 20 described later), the left guide plate 220 is not shown for convenience of explanation. The guide plate 220 is formed with a sub-frame side guide surface 221, a sub-frame side hook 222, a notch 223, and an engaged hole 224.

  The sub-frame side guide surface 221 shown in FIGS. 7 and 8 is for guiding the main frame-side pin 131 to the mounting position when the sub-frame unit 200 is mounted on the main frame 100. The sub-frame-side guide surface 221 is formed on the lower end portion of the guide plate 220 in a planar shape with the surface facing substantially downward. More specifically, the sub-frame-side guide surface 221 is formed in a slope shape whose height in the vertical direction decreases toward the front. The sub-frame side guide surface 221 is formed to be parallel to the main frame-side guide surface 133. The subframe-side guide surface 221 is formed to extend from the rear end portion of the guide plate 220 to the vicinity of the front end portion (more specifically, a subframe-side hook 222 described later).

  The sub-frame side hook 222 is a part that holds the main frame-side pin 131 of the main frame 100. The sub-frame side hook 222 is formed at the front lower portion of the guide plate 220. The sub-frame side hook 222 is formed in a substantially U shape with the rear opened in a side view, and can support a main frame-side pin 131 described later from below. The subframe side hook 222 is connected to the front end portion of the subframe side guide surface 221.

  The notch 223 shown in FIG. 8 regulates the movement of a detent pin 260 described later. The notch 223 is formed so that the upper end of the guide plate 220 is opened. The notch 223 is formed to extend downward from the upper end of the guide plate 220.

  The engaged hole 224 shown in FIG. 8 regulates the swing range of the lock bar 240 described later. The engaged hole 224 is formed so as to penetrate the guide plate 220 in the left-right direction. The engaged hole 224 is formed in a partial annular shape with a central angle of about 65 ° centered on a rocking center (rocking shaft 241) of a lock bar 240 described later in side view. The engaged hole 224 is formed on the rear upper side of the swing shaft 241.

  The thumb 230 shown in FIGS. 4 to 8 holds the main frame side pin 131 immovably on the sub frame side hook 222 (to prevent the main frame side pin 131 from being detached from the sub frame side hook 222). Is. The thumb 230 is formed in a substantially trapezoidal shape in a side view. The thumb 230 is provided between the pair of left and right guide plates 220. On the top of the thumb 230, a swing shaft 231 is formed with the axis line directed in the left-right direction. The thumb 230 is supported on the subframe 210 so as to be swingable about the axis of the swing shaft 231 above the main frame side pin 131. The thumb 230 is biased by a biasing means (not shown) such as a spring in a direction in which the thumb 230 swings counterclockwise in a left side view (see FIG. 8). In addition to the swing shaft 231, the thumb 230 is formed with an engagement groove 232 and a thumb side contact surface 233.

  The engagement groove 232 shown in FIGS. 5 to 8 is a portion that engages with the main frame side pin 131. The engagement groove 232 is formed in the lower part of the thumb 230 and in the front and rear center part. The engagement groove 232 is formed in a semicircular arc shape with the lower part opened in a side view. The engagement groove 232 is formed so that the diameter thereof is substantially the same as the diameter of the main frame side pin 131 in a side view.

  The thumb side contact surface 233 shown in FIGS. 6 and 8 is a rear side surface of the thumb 230. The thumb side contact surface 233 is formed in a planar shape with the surface facing rearward or a curved surface having a larger radius than an arc of a lock bar side contact surface 243 described later.

  The lock bar 240 shown in FIGS. 5 to 8 regulates the swing of the thumb 230. The lock bar 240 is formed in a substantially pentagonal shape in a side view. The right surface of the lock bar 240 is provided to face the left surface of the right guide plate 220. The thickness of the lock bar 240 in the left-right direction is smaller than the thickness of the thumb 230 in the left-right direction.

  A rocking shaft 241 having an axis line in the left-right direction is formed at a substantially central portion of the lock bar 240. The lock bar 240 is supported by the subframe 210 so as to be swingable about the axis of the swing shaft 241 at the upper rear side of the thumb 230. The lock bar 240 is urged by a biasing means (not shown) such as a spring in a direction in which the lock bar 240 swings counterclockwise in a left side view (see FIG. 8). The urging force in the counterclockwise direction viewed from the left side received by the lock bar 240 is set to be larger than the urging force in the counterclockwise direction viewed from the left side viewed by the thumb 230. In addition to the swing shaft 241, the lock bar 240 is formed with a protruding portion 242, a lock bar-side contact surface 243, an insertion pin 244, and a first locked portion 245.

  The protrusions 242 shown in FIGS. 6 and 8 are for pressing and swinging a control plate 250 described later. The front portion of the lock bar 240 is formed thicker than the other portions of the lock bar 240, and the protruding portion 242 has a portion of the thick portion protruding toward the swing shaft 241. Formed (see FIG. 6).

  The lock bar side contact surface 243 shown in FIGS. 6 and 8 is a front side surface of the lock bar 240. The lock bar-side contact surface 243 is formed in an arc shape centering on the swing shaft 241 in a side view. The lock bar side contact surface 243 is formed so as to be able to contact the thumb side contact surface 233 in the mounted state.

  The insertion pin 244 shown in FIG. 8 is inserted into the engaged hole 224 of the guide plate 220. The insertion pin 244 is formed in a columnar shape protruding rightward from the left surface of the lock bar 240. The rocking range of the lock bar 240 is restricted by the insertion pin 244 and the engaged hole 224.

  The first locked portion 245 shown in FIGS. 6 and 8B is a portion for locking with a detent pin 260 described later. The first locked portion 245 is formed on the outer peripheral portion of the lock bar 240. The first locked portion 245 is formed so as to be positioned in front of the notch 223 in the mounted state. The first locked portion 245 is formed in a slope shape that rises outward in the radial direction as the outer peripheral surface of the lock bar 240 moves in the clockwise direction in the left side view.

  The control plate 250 shown in FIGS. 5 to 8 controls the swing of the lock bar 240. The control plate 250 is formed in a substantially circular plate shape with the plate surface facing in the left-right direction. The control plate 250 is provided so as to be swingable around the swing shaft 241 of the lock bar 240. The right surface of the control plate 250 is provided to face the left surface of the lock bar 240. The left surface of the control plate 250 is formed to be substantially flush with the left surface of the protrusion 242 of the lock bar 240. The control plate 250 is formed with a notch 251, a second locked portion 252, and a third locked portion 253.

  The cutout 251 shown in FIGS. 6 and 8A is a portion for enabling the control plate 250 to rotate together with the lock bar 240. The notch 251 is formed so that the front end of the control plate 250 is opened. The notch 251 is formed in an arc shape having a central angle of about 30 ° with the swing shaft 241 as the center. The notch 251 is formed at a position facing the protrusion 242 of the lock bar 240 so that the protrusion 242 can be accommodated.

  The second locked portion 252 shown in FIGS. 6 and 8B is a portion for locking with a detent pin 260 described later. The second locked portion 252 is formed on the outer peripheral portion of the control plate 250. The second locked portion 252 is formed at a position overlapping the notch portion 223 in a side view in the mounted state. The second locked portion 252 is formed in the shape of a slope that rises radially outward as the outer peripheral surface of the control plate 250 moves counterclockwise as viewed from the left side.

  The third locked portion 253 shown in FIGS. 6 and 8B is a portion for locking with a detent pin 260 described later. The third locked portion 253 is formed on the outer peripheral portion of the control plate 250. The third locked portion 253 is formed so as to be positioned in front of the notch 223 in the mounted state. More specifically, the third locked portion 253 is formed with an interval of about 35 ° in the clockwise direction in the left side view with respect to the second locked portion 252. The third locked portion 253 is formed in a slope shape that rises outward in the radial direction as the outer peripheral surface of the control plate 250 moves in the clockwise direction in the left side view.

  The detent pin 260 shown in FIGS. 6 and 8A is for restricting the rocking of the lock bar 240 and the control plate 250. The detent pin 260 is formed in a cylindrical shape. The detent pin 260 is provided such that both left and right end portions thereof are inserted into the notch portions 223 of the pair of left and right guide plates 220 with the axis line directed in the left-right direction. The detent pin 260 is urged in a downward direction along the notch 223 by an urging means (not shown) such as a spring. The detent pin 260 is in contact with the outer peripheral surface of the lock bar 240 by the biasing force received by the detent pin 260 in the mounted state.

  4 and 6 is for swinging the lock bar 240 when the sub-frame unit 200 is removed from the main frame 100. The operation tool 270 includes a grip portion 271, an insertion pin 272, and a connection plate 273.

  The grip part 271 shown in FIG. 4 is a part that the operator grips. The grip portion 271 is provided outside the subframe 210 (outside in the left-right direction of the vehicle body 1). The grip portion 271 is formed in an appropriate shape that is easy for an operator to grip.

  The insertion pin 272 is a part that is inserted into the restriction hole 212 of the subframe 210. The insertion pin 272 is formed in a cylindrical shape whose axis is directed in the left-right direction. The insertion pin 272 is connected to the grip portion 271 via a connection plate 273 described later, and is inserted into the restriction hole 212 of the subframe 210. Therefore, the movement range of the insertion pin 272 is restricted by the restriction hole 212.

  The connection plate 273 connects the grip portion 271 and the insertion pin 272 and the swing shaft 241 of the lock bar 240. The connection plate 273 is formed in a plate shape with the plate surface facing in the left-right direction. A grip 271 and an insertion pin 272 are connected to one end of the connection plate 273. On the other hand, the swing shaft 241 of the lock bar 240 is connected to the other end of the connection plate 273 so as to rotate together with the lock bar 240 in the movement range of the insertion pin 272.

  Next, a method of removing the front loader 20 (more specifically, a portion of the front loader 20 excluding the main frame 100) from the vehicle body 1 will be described with reference to FIGS.

  7 and 8 show a state where the sub-frame unit 200 is attached to the main frame 100 (attached state). In the mounted state, the main frame side pin 131 is held by the subframe side hook 222 and the subframe side pin 211 is held by the main frame side hook 132 (see FIG. 7).

  At this time, since the lock bar 240 is urged counterclockwise as viewed from the left side, it is the most forwardly lowered position (restricted position) within the movement range determined by the insertion pin 244 and the engaged hole 224. ). The lock bar 240 restricts the swinging of the thumb 230 in the counterclockwise direction when viewed from the left side when the lock bar side contact surface 243 contacts the thumb side contact surface 233. Thereby, the thumb 230 is held at a position (engagement position) where the engagement groove 232 engages with the main frame side pin 131, and prevents the main frame side pin 131 from being detached from the subframe side hook 222. . At this time, the main frame side pin 131 is fixed at three points including the left and right subframe side hooks 222 and the engaging groove 232 located therebetween.

  At this time, the thumb side contact surface 233 and the lock bar side contact surface 243 are formed so that the pressing force received by the lock bar 240 from the thumb 230 is directed toward the swing center (swing shaft 241) of the lock bar 240. ing. Thereby, the lock bar 240 can be prevented from swinging due to the pressing force received by the lock bar 240 from the thumb 230.

  7 and 8, when the operating tool 270 is swung 30 ° clockwise along the restriction hole 212 in the left side view, the lock bar 240 is moved in the clockwise direction in the left side view. It swings 30 ° in the upward direction (see FIG. 9A).

  When the lock bar 240 swings 30 ° in the clockwise direction when viewed from the left side from the mounted state, the detent pin 260 is locked to the first locked portion 245 of the lock bar 240 (see FIG. 9B). Here, the biasing force in the counterclockwise direction viewed from the left side received by the lock bar 240 is set to such a size that the detent pin 260 cannot get over the first locked portion 245. For this reason, the lock bar 240 is restricted from swinging in the counterclockwise direction in the left side view (forward downward direction) by the detent pin 260 and the first locked portion 245. Therefore, the lock bar 240 is held at a position (position shown in FIG. 9A) that is swung by 30 ° in the clockwise direction when viewed from the left side.

  At this time, the control plate 250 is restricted from swinging in the counterclockwise direction when viewed from the left side (forward downward direction) by the protrusion 242 of the lock bar 240 (see FIG. 9A). Further, the control plate 250 is restricted from swinging in the clockwise direction in the left side view (forward upward direction) by the detent pin 260 being locked to the second locked portion 252 (FIG. 9B). )reference).

  In the state shown in FIG. 9, the vehicle body 1 is moved backward with the front loader 20 (portion excluding the main frame 100) lowered to the ground. Then, the main frame 100 (main frame side pin 131) moves rearward relative to the subframe unit 200 while pushing up the rear part of the thumb 230 (see FIG. 10A). Then, the engagement between the thumb 230 and the main frame 100 (main frame side pin 131) is released. The thumb 230 swings counterclockwise as viewed from the left side by the biasing force received by the thumb 230 and abuts against the lock bar 240.

  Here, the biasing force received by the thumb 230 in the counterclockwise direction in the left side view (forward downward direction) is greater than the biasing force in the counterclockwise direction in the left side view received by the lock bar 240 (forward downward direction). Is set to For this reason, the front part of the lock bar 240 is pushed up by the thumb 230. As a result, the lock bar 240 starts to swing in the clockwise direction (forward upward direction) when viewed from the left side. At this time, the control plate 250 starts to swing in the clockwise direction (forward upward direction) when viewed from the left side integrally with the lock bar 240 when the notch 251 is pushed by the protrusion 242.

  When the thumb 230 further pushes up the front portion of the lock bar 240, the control plate 250 is further pressed clockwise by the protrusion 242 of the lock bar 240 as viewed from the left side. Here, the difference between the biasing force received by the thumb 230 in the counterclockwise direction viewed from the left side (forward downward direction) and the biasing force received by the lock bar 240 in the counterclockwise direction viewed from the left side (forward downward direction) is: The detent pin 260 is set to have a size that allows it to get over the second locked portion 252 of the control plate 250. Therefore, when the control plate 250 is further pressed by the protruding portion 242 of the lock bar 240, the detent pin 260 gets over the second locked portion 252 (see FIG. 11B), and the left side of the lock bar 240 It will rotate together in the clockwise direction (front-up direction) in the plan view (see FIG. 11A).

  Further, when the thumb 230 pushes up the front portion of the lock bar 240, the lock bar 240 is moved to the most forward position (regulation release position) in the swing range determined by the insertion pin 244 and the engaged hole 224. It swings (see FIG. 12A). Specifically, the restriction release position is a position that is swung by 65 ° in the clockwise direction in the left side view from the most forward-downward position (restriction position) shown in FIG. At this time, the lock bar 240 is restricted by the engaged hole 224 from swinging in the clockwise direction in the left side view (forward upward direction). Further, the lock bar 240 is restricted from swinging counterclockwise in the left side view (forward downward direction) by the pressing force of the thumb 230. The thumb 230 is held at a position (release position) where the lock bar 240 is pushed up to the highest position.

  At this time, the control plate 250 rotates together with the lock bar 240 and swings from the mounted state to a position where the control plate 250 swings by 35 ° in the clockwise direction (front upward direction) when viewed from the left side. At this time, when the detent pin 260 is locked to the third locked portion 253, the control plate 250 is restricted from swinging counterclockwise in the left side view (forward downward direction) (FIG. 12 ( b)).

  In this way, with the front loader 20 (the part excluding the main frame 100) lowered to the ground, the operation tool 270 is operated to unlock the thumb 230 and the main frame side pin 131, and then the vehicle body 1 is moved backward. By doing so, the sub-frame unit 200, the boom 300, and the bucket 400 of the front loader 20 can be easily detached from the main frame 100.

  Next, a method for mounting the front loader 20 (more specifically, a portion of the front loader 20 excluding the main frame 100) to the vehicle body 1 will be described with reference to FIGS.

  As shown in FIG. 13, with the front loader 20 (the part excluding the main frame 100) removed from the main frame 100 and lowered to the ground, the vehicle body 1 is advanced and the main frame 100 is brought close to the subframe unit 200.

  As shown in FIG. 14, when the vehicle body 1 further moves forward, the main frame side pin 131 comes into contact with the subframe side guide surface 221. The main frame side pin 131 is guided to the sub frame side hook 222 by the sub frame side guide surface 221. Further, when the vehicle body 1 moves forward, the main frame side guide surface 133 comes into contact with the sub frame side pin 211. The subframe side pin 211 is guided to the mainframe side hook 132 by the mainframe side guide surface 133.

  Here, since the sub-frame side guide surface 221 is formed in a front-declining slope shape, the main frame-side pin 131 is likely to come into contact with the sub-frame side guide surface 221 when the vehicle body 1 is advanced. Even if the height of the subframe unit 200 with respect to the main frame 100 is slightly deviated, the main frame side pin 131 can be brought into contact with the subframe side guide surface 221. The hook 222 can be easily guided.

  Similarly, since the main frame side guide surface 133 is also formed in a front-declining slope, the subframe side pin 211 is likely to come into contact with the main frame side guide surface 133 when the vehicle body 1 is advanced. Even if the height of the subframe unit 200 with respect to the mainframe 100 is slightly deviated, the subframe side pin 211 can be brought into contact with the mainframe side guide surface 133. The hook 132 can be easily guided.

  As shown in FIG. 15, the main frame side pin 131 contacts the thumb 230 while being guided by the subframe side hook 222. Then, the main frame side pin 131 presses the thumb 230 forward, and starts to swing in the clockwise direction (front upward direction) when viewed from the left side. The lock bar 240 tends to swing counterclockwise in the left side view (forward downward direction) following the thumb 230 by the biasing force received by the lock bar 240.

  At this time, the detent pin 260 is locked to the third locked portion 253 of the control plate 250 (see FIG. 15B). Here, in a side view, the diameter of the portion of the outer peripheral surface of the lock bar 240 adjacent to the rear end of the first locked portion 245 (the distance between the axis of the swing shaft 241) is the control plate 250. Is formed so as to be smaller than the diameter of the portion adjacent to the front end of the third locked portion 253. For this reason, the lock bar 240 does not lock the detent pin 260 with the first locked portion 245, and swings in the counterclockwise direction (downward direction in the left side view) following the thumb 230. (See FIGS. 16A and 16B).

  When the vehicle body 1 further moves forward, the thumb 230 further swings in the clockwise direction (forward upward direction) when viewed from the left side by the forward pressing force of the main frame side pin 131, and the lock bar 240 follows the thumb 230. It swings counterclockwise as viewed from the left side (forward downward direction) (see FIG. 17A). The control plate 250 is pressed by the protrusion 242 of the lock bar 240 and tries to rotate together with the lock bar 240 in the counterclockwise direction (downward direction in the left side view).

  Here, the biasing force in the counterclockwise direction (forward downward direction) viewed from the left side received by the lock bar 240 is set to such a size that the detent pin 260 can get over the third locked portion 253. Therefore, when the control plate 250 is further pressed by the protruding portion 242 of the lock bar 240, the detent pin 260 gets over the third locked portion 253 (see FIG. 17B), so It is possible to rotate in the counterclockwise direction (front-down direction) in a plan view.

  When the vehicle body 1 further advances, the thumb 230 returns to the engagement position and engages with the main frame side pin 131 (see FIG. 18). The lock bar 240 follows the thumb 230 and returns to the most forwardly lowered position (regulation position) of the lock bar 240 to restrict the swing of the thumb 230. Thus, the main frame side pin 131 is held by the thumb 230 in an immovable manner on the sub frame side hook 222. Therefore, the main frame side pin 131 is prevented from being detached from the sub frame side hook 222.

  Thus, the subframe side pin 211 is engaged with the main frame side hook 132 and the mainframe side pin 131 is engaged with the subframe side hook 222. The engagement between the sub-frame side hook 222 and the main frame-side pin 131 is held by the engagement groove 232 of the thumb 230.

  In this way, the subframe unit 200 and the boom 300 and the bucket 400 provided in the subframe unit 200 are simply moved forward while the front loader 20 (the portion excluding the main frame 100) is lowered to the ground. Can be easily attached to the main frame 100. Further, as described above, the operation tool 270 is operated to release the lock by the lock bar 240, and the vehicle body 1 is simply moved backward while the front loader 20 (the portion excluding the main frame 100) is lowered to the ground. The boom 300 and the bucket 400 provided in the frame unit 200 and the subframe unit 200 can be easily detached from the main frame 100.

  Accordingly, when the front loader 20 is attached or detached, conventional operations such as operation of the boom 300 by hydraulic pressure for alignment with the main frame 100 and insertion / removal of a pin for fixing the boom 300 to the main frame 100 are unnecessary. be able to. Moreover, it is not necessary for the operator to get on and off the cabin 10 for these operations. Therefore, it is possible to reduce the number of work steps when the front loader 20 is attached and detached, and the work time associated therewith.

  Further, since the main frame 100 and the sub-frame unit 200 are configured to align with each other, the alignment between the main frame 100 and the sub-frame unit 200 can be performed smoothly.

As described above, the attachment / detachment structure of the front loader 20 according to the present embodiment is such that the subframe 210 that supports the boom 300 is engaged with the main frame 100 provided in the vehicle body 1, the main frame 100, A thumb 230 (engagement member) that is supported so as to be movable between the release position and the release position from which the engagement is released, and is biased in the release direction from the engagement position toward the release position. 210 is movable between a restriction position that restricts movement of the thumb 230 from the engagement position in the release direction and a restriction release position that permits the thumb 230 to move to the release position. And a supported lock bar 240 (regulating member).
By comprising in this way, the attachment or detachment work to the vehicle body 1 can be facilitated. Specifically, the thumb 230 can be easily moved to the release position simply by moving the lock bar 240 to the restriction release position, and as a result, the engagement between the thumb 230 and the main frame 100 can be released.

Further, the lock bar 240 is formed so as to abut the thumb 230 located at the engagement position at the restriction position and restrict the movement of the thumb 230 in the release direction. .
With this configuration, the movement of the thumb 230 in the release direction can be restricted with a simple structure.

The thumb 230 is formed on the sub-frame 210 so as to be swingable between the engagement position and the release position.
With this configuration, the thumb 230 can be engaged with the main frame 100 with a simple structure, and the engagement between the thumb 230 and the main frame 100 can be released.

The lock bar 240 is formed on the sub-frame 210 so as to be swingable between the restriction position and the restriction release position.
With this configuration, it is possible to restrict the movement of the thumb 230 from the engagement position in the release direction and to release the restriction on the movement of the thumb 230 with a simple structure.

In addition, when the main frame 100 moves relative to the sub-frame 210, the thumb 230 is pressed by the main frame 100 to move from the release position toward the engagement position. Is formed.
With this configuration, the thumb 230 can be easily engaged with the main frame 100 by bringing the vehicle body 1 close to the subframe 210 removed from the vehicle body 1 (main frame 100).

The lock bar 240 is urged in a regulation direction from the regulation release position toward the regulation position, and follows the thumb 230 when the thumb 230 moves from the release position toward the engagement position. And it is formed so that it may move in the regulation direction from the regulation release position.
With this configuration, when the thumb 230 is returned to the engagement position and engaged with the main frame 100, the lock bar 240 can be returned to the restricting position, and the lock bar 240 releases the thumb 230. The movement to can be regulated.

In addition, the front loader 20 attachment / detachment structure according to the present embodiment includes a holding mechanism (a thumb 230, a lock bar 240, a control plate 250, and a detent pin 260) that holds the lock bar 240 at the restriction position and the restriction release position. It has.
With this configuration, the thumb 230 can be held at the engagement position by holding the lock bar 240 at the restriction position. Further, the thumb 230 can be held at the release position by holding the lock bar 240 at the restriction release position.

Further, the attachment / detachment structure of the front loader 20 according to the present embodiment includes a holding mechanism that holds the lock bar 240 at the restriction position and the restriction release position, and the holding mechanism includes the restriction position and the restriction release position. A detent mechanism (a first locked portion 245 and a detent pin 260) for locking the lock bar 240 so as not to move in the restricting direction, and the thumb 230 includes the lock In a state where the bar 240 is locked at the intermediate position by the detent mechanism, when the bar 240 moves in the release direction, the lock bar 240 is pressed and moved to the restriction release position.
By being configured in this way, it is possible to suppress the thumb 230 from moving to the release position vigorously.

The detent mechanism includes a detent pin 260 (locking portion) urged so as to come into contact with the outer peripheral portion of the lock bar 240, and the lock bar 240. A first locked portion 245 (locked portion) to be locked.
With this configuration, the lock bar 240 can be held at the intermediate position by the detent pin 260 being locked to the first locked portion 245.

Further, when the lock bar 240 moves from the restriction release position toward the restriction direction, the detent pin 260 is prevented from being locked to the first locked portion 245 at the intermediate position. A control plate 250 (control member) is provided.
With this configuration, when the lock bar 240 is moved from the restriction position toward the restriction release position, the lock bar 240 can be held at the intermediate position, and the lock bar 240 can be held at the restriction release position. In the case where the lock bar 240 is moved toward the restriction position, the lock bar 240 can be moved to the restriction position without being held at the intermediate position.

Further, the control plate 250 presses the detent pin 260 against the biasing force received by the detent pin 260 at the intermediate position, so that the detent pin 260 is engaged with the first locked portion 245. It is formed so as to avoid being stopped.
With this configuration, when the lock bar 240 is moved from the restriction release position to the restriction position with a simple structure, the lock bar 240 is moved to the restriction position without being held at the intermediate position. Can be made.

Further, the lock bar 240 is formed such that the pressing force received from the thumb 230 located at the engagement position is directed toward the swing center of the lock bar 240 at the restriction position.
With this configuration, it is possible to prevent the lock bar 240 from swinging due to the pressing force received from the thumb 230 when the lock bar 240 restricts the swing of the engaging member. .

Moreover, the attachment / detachment structure of the front loader 20 according to the present embodiment includes an operation tool 270 for moving the lock bar 240.
With this configuration, the lock bar 240 can be easily moved using the operation tool 270.

Further, the front loader 20 according to the present embodiment can be attached to and detached from the main frame 100 by the main frame side pin 131 (first held portion) provided in the main frame 100 provided in the vehicle body 1. A subframe side pin 211 (second held portion) provided on the subframe 210 that supports the boom 300, and a subframe side hook 222 provided on the subframe 210 and holding the mainframe side pin 131. (First holding portion), a main frame side hook 132 (second holding portion) provided on the main frame 100 and holding the sub frame side pin 211, and the sub frame 210 are attached to the main frame 100. At the time of mounting, the main frame side pin 131 is moved to the sub frame side hook 222. An inner subframe-side guide surface 221 (first guide portion) and a mainframe-side guide surface 133 (second guide portion) for guiding the subframe-side pin 211 to the mainframe-side hook 132 at the time of mounting. And.
By comprising in this way, the attachment or detachment work to the vehicle body 1 can be facilitated. Specifically, the main frame 100 and the subframe 210 can be easily aligned when mounted on the vehicle body 1. Further, since the main frame 100 and the sub frame 210 are aligned with each other, the alignment between the main frame 100 and the sub frame 210 can be facilitated.

Each of the sub-frame side hook 222 and the main frame-side hook 132 is formed to support the main frame-side pin 131 and the sub-frame side pin 211 from below.
With this configuration, the main frame 100 can support the subframe 210 from below.

The sub-frame-side guide surface 221 is provided on the sub-frame 210, and the main-frame-side pin 131 (main-frame-side held portion) is attached to the sub-frame-side hook 222 (sub-frame-side holding portion) at the time of mounting. ), And the main frame side guide surface 133 is provided on the main frame 100, and the subframe side pin 211 (subframe side held) when mounted. Part) to the main frame side hook 132 (main frame side holding part) (main frame side guide part).
With this configuration, the main frame 100 and the sub frame 210 are aligned with each other, so that the alignment between the main frame 100 and the sub frame 210 can be facilitated.

The main frame side guide surface 133 is formed so as to guide to the main frame side hook 132 while supporting the sub frame side pin 211 from below at the time of mounting.
With this configuration, the main frame 100 and the subframe 210 can be aligned while supporting the subframe 210 from below when mounted on the vehicle body 1, thereby improving workability. Can do.

The subframe-side guide surface 221 is formed to guide the mainframe-side pin 131 to the subframe-side hook 222 while being supported from below by the mainframe-side pin 131 when mounted. It is what.
With this configuration, the main frame 100 and the subframe 210 can be aligned while supporting the subframe 210 from below when mounted on the vehicle body 1, thereby improving workability. Can do.

Further, each of the main frame side guide surface 133 and the sub frame side guide surface 221 is formed in a slope shape in which the height in the up and down direction becomes lower toward the front direction of the vehicle body 1.
With such a configuration, when the vehicle body 1 is moved forward and the main frame 100 is brought close to the sub frame 210 when mounted on the vehicle body 1, each held portion (the main frame side pin 131 and the sub frame) The side pins 211) can easily come into contact with the respective guide portions (subframe side guide surface 221 and main frame side guide surface 133). Therefore, each held portion can be easily guided to each holding portion (subframe side hook 222 and main frame side hook 132).

The main frame 100 includes a recess 133 a formed between the main frame side guide surface 133 and the main frame side pin 131.
With such a configuration, it is possible to prevent the main frame side pin 131 from being deformed or damaged due to a contact impact or the like when being attached to or detached from the vehicle body 1.

Further, the attachment / detachment structure of the front loader 20 according to the present embodiment is provided in the subframe 210, and when the main frame side pin 131 is guided to the subframe side hook 222 by the subframe side guide surface 221, A thumb 230 (engaging member) that engages with the main frame side pin 131 to prevent the main frame side pin 131 from being detached from the sub frame side hook 222 is provided.
With this configuration, it is possible to prevent the main frame side pin 131 from being detached from the sub frame side hook 222.

Moreover, the front loader 20 according to the present embodiment includes the detachable structure according to the present embodiment.
By being configured in this way, it is possible to provide the front loader 20 that can facilitate the attaching and detaching work to the vehicle body 1.

The tractor (work vehicle) according to the present embodiment includes a front loader 20.
With this configuration, it is possible to provide a tractor work vehicle that can facilitate the attaching and detaching work of the front loader 20 to the vehicle body 1.

  As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said structure, A various change is possible within the range of the invention described in the claim.

  For example, in the present embodiment, the thumb 230 is engaged with the main frame side pin 131 and released from the engagement by swinging. However, the manner of movement of the thumb 230 is limited to swinging. For example, it may be performed by sliding with respect to the sub-frame 210.

  In the present embodiment, the lock bar 240 controls the swing of the thumb 230 and releases the control by the swing. However, the movement mode of the lock bar 240 is limited to the swing. For example, it may be performed by sliding with respect to the subframe 210.

  In this embodiment, the thumb 230 is provided inside (between) the two guide plates 220. However, the present invention is not limited to this. For example, one guide plate 220 may be provided. The thumb 230 may be provided outside the guide plate 220. However, in terms of the stability of the support of the subframe unit 200 with respect to the main frame 100, the thumb 230 is provided inside (between) the guide plates 220 provided in the pair of left and right subframes 210 as in the present embodiment. The provided structure is preferred.

  Further, in the present embodiment, the lock bar 240 is provided at substantially the same position in the left-right direction as the thumb 230 inside the two guide plates 220. However, the present invention is not limited to this. The lock bar 240 may be provided at different positions in the left-right direction (for example, the thumb 230 is pressed from the left-right direction to restrict swinging). However, in terms of the ease of regulating the swing of the thumb 230, etc., as in this embodiment, the thumb 230 and the left and right directions are generally arranged inside the guide plates 220 provided on the pair of left and right subframes 210, respectively. A structure in which the lock bar 240 is provided at the same position (on the same plane) is preferable.

  In the present embodiment, the control plate 250 swings about the same axis as the lock bar 240 (swing shaft 241). However, a separate swing shaft may be provided for the control plate 250. However, the control plate 250 may swing about the same axis as the lock bar 240 as in the present embodiment in terms of ease of control of swinging of the lock bar 240 and reduction in the number of parts. preferable.

  In the present embodiment, the control plate 250 is provided on one side of the lock bar 240, but may be provided on both the left and right sides of the lock bar 240.

  In the present embodiment, each held portion (the main frame side pin 131 and the sub frame side pin 211) is provided on different members (the main frame 100 and the sub frame 210). It may be provided. Each holding portion (the sub-frame side hook 222 and the main frame-side hook 132) may also be provided on the same member. For example, each held portion (pin) may be provided on the main frame 100 side, and each holding portion (hook) may be provided on the subframe 210 side. Alternatively, each held portion (pin) may be provided on the subframe 210 side, and each holding portion (hook) may be provided on the main frame 100 side.

  In the present embodiment, the thumb-side contact surface 233 is formed in a flat shape. However, as shown in FIG. 19, the radius of curvature of the lock-bar-side contact surface 243 is a side view. It may be formed in substantially the same arc shape. Accordingly, the lock bar 240 can be swung in the forward upward direction without being obstructed by the thumb 230, and the contact area between the thumb side contact surface 233 and the lock bar side contact surface 243 can be reduced in the mounted state. Since the number can be increased, the swing of the thumb 230 can be easily regulated.

As described above, the attachment / detachment structure of the front loader 20 according to the present embodiment is formed such that the thumb 230 is supported by the subframe 210 so as to be swingable between the engagement position and the release position. The lock bar 240 is formed on the sub-frame 210 so as to be swingable between the restriction position and the restriction release position, and the rocking shaft 231 of the thumb 230 is formed. Is provided so as to be parallel to the swing shaft 241 of the lock bar 240, and the lock bar side contact surface 243 (the contact portion of the lock bar 240 with the thumb 230) When viewed in the direction of the movement axis, the lock bar 240 is formed in an arc shape centered on the swinging shaft 241, and the thumb side contact surface 233 (the contact portion of the thumb 230 with the lock bar 240). ), In the pivot axis direction as viewed in the thumb 230, in which the radius of curvature is formed on a radius of curvature substantially the same arc-shaped the lock bar side abutment surface 243.
With this configuration, the lock bar 240 can be swung without being blocked by the thumb 230.

DESCRIPTION OF SYMBOLS 1 Car body 20 Front loader 100 Main frame 131 Main frame side pin 132 Main frame side hook 133 Main frame side guide surface 133a Concave part 210 Sub frame 211 Sub frame side pin 221 Sub frame side guide surface 222 Sub frame side hook 230 Thumb 240 Lock bar 245 First locked portion 250 Control plate 260 Detent pin 270 Operation tool 300 Boom

Claims (16)

The sub-frame that supports the boom is supported movably between an engagement position that engages with a main frame provided on the vehicle body and a release position that is disengaged from the main frame. An engagement member biased in a release direction from the engagement position toward the release position;
Between the restriction position for restricting the engagement member from moving from the engagement position to the release direction and the restriction release position for allowing the engagement member to move to the release position. A regulating member supported so as to be movable in
Comprising
Front loader attachment / detachment structure. The regulating member is
In the restricting position, it is configured to abut against the engaging member located in the engaging position and restrict the movement of the engaging member in the releasing direction.
The front loader attachment / detachment structure according to claim 1. The engaging member is
The sub frame is formed so as to be swingable between the engagement position and the release position.
The front loader attachment / detachment structure according to claim 1 or 2. The regulating member is
The sub-frame is formed so as to be swingable between the restriction position and the restriction release position.
The front loader attachment / detachment structure according to any one of claims 1 to 3. The engaging member is
When the main frame is relatively moved so as to be close to the sub-frame, the main frame is pressed by the main frame so as to move from the release position to the engagement position.
The front loader attachment / detachment structure according to any one of claims 1 to 4. The regulating member is
Urged in a regulation direction from the regulation release position to the regulation position,
When the engagement member moves from the release position toward the engagement position, the engagement member follows the engagement member and moves from the restriction release position to the restriction direction.
The front loader attachment / detachment structure according to any one of claims 1 to 5. A holding mechanism for holding the restriction member at the restriction position and the restriction release position;
The front loader attachment / detachment structure according to any one of claims 1 to 6. A holding mechanism for holding the restriction member at the restriction position and the restriction release position;
The holding mechanism is
A detent mechanism for locking the restriction member so as not to move in the restriction direction at an intermediate position between the restriction position and the restriction release position;
The engaging member is
In a state where the restriction member is locked at the intermediate position by the detent mechanism, when the movement is made in the release direction, the restriction member is pressed and moved to the restriction release position.
The attachment / detachment structure of the front loader according to claim 6. The detent mechanism is
A locking portion biased to abut against the outer peripheral portion of the restriction member;
A locked portion that is provided on the restriction member and locked by the locking portion at the intermediate position;
Comprising
The front loader attachment / detachment structure according to claim 8. A control member that prevents the locking portion from being locked to the locked portion at the intermediate position when the restriction member moves from the restriction release position toward the restriction direction;
The front loader attachment / detachment structure according to claim 9. The control member is
At the intermediate position, it is formed so as to avoid the locking portion being locked to the locked portion by pressing the locking portion against the biasing force received by the locking portion. ing,
The front loader attachment / detachment structure according to claim 10. The engaging member is
The sub frame is formed so as to be swingable between the engagement position and the release position,
The regulating member is
The sub-frame is formed so as to be swingable between the restriction position and the restriction release position,
The swing shaft of the engaging member is
Provided to be parallel to the swing axis of the regulating member,
The contact portion of the restriction member with the engagement member is
When viewed in the direction of the swing axis of the restricting member, the restricting member is formed in an arc shape centered on the swing axis of the restricting member,
The contact portion of the engagement member with the restriction member is
When the engagement member is viewed in the swing axis direction, the radius of curvature is formed in an arc shape that is substantially the same as the radius of curvature of the contact portion of the restriction member with the engagement member.
The front loader attachment / detachment structure according to any one of claims 1 to 11. The regulating member is
In the restriction position, the pressing force received from the engagement member located at the engagement position is formed so as to be directed toward the swing center of the restriction member.
The attachment / detachment structure of the front loader according to claim 12. Comprising an operating tool for moving the regulating member;
The front loader attachment / detachment structure according to any one of claims 1 to 13.   A front loader comprising the detachable structure according to any one of claims 1 to 14.   A work vehicle comprising the front loader according to claim 15.

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