JP2011126324A - Tractor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple structure in which a PTO shaft cover included in a tractor easily fixed to a protective position or open position and the number of parts is small. <P>SOLUTION: A fixing mechanism for fixing a PTO shaft cover 62 included in a tractor has a cover side projection 76 positioned on the PTO shaft cover 62 and has a first recess 77 and a second recess 78 positioned on the side of a mission case 21 corresponding to the cover side projection 76. The fixing mechanism fixes the PTO shaft cover 62 at the protective position by fitting the cover side projection 76 to the first recess 77 by the elastic force of the PTO shaft cover 62. Also, by fitting the cover side projection 76 to the second recess 78 by the elastic force of the PTO shaft cover 62, the fixing mechanism fixes the PTO shaft cover 62 at the open position. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a PTO shaft cover provided in a tractor.

  2. Description of the Related Art Conventionally, a tractor to which an attachment (work machine) such as a rotary can be connected includes a PTO shaft for transmitting engine driving force from the tractor body side and a PTO shaft cover for protecting the PTO shaft. It has been. Patent Document 1 discloses a tractor provided with this type of PTO shaft cover.

  The tractor disclosed in Patent Document 1 includes a PTO shaft cover configured to be rotatable in the vertical direction, and a lock pin for fixing the PTO shaft cover in a protected position or an open position. An engagement hole is formed in the PTO shaft cover, and the PTO shaft cover can be fixed at the protection position or the open position by inserting the lock pin into the engagement hole.

Japanese Utility Model Publication No. 53-24038

  However, in the configuration of Patent Document 1, the operator moves the PTO shaft cover from the fixed position unless the PTO shaft cover is rotated with the other hand while unlocking the lock pin with one hand. I could not. It is very troublesome to perform such work every time the PTO shaft cover is rotated from the fixed position, and there is room for improvement from the viewpoint of improving workability.

  Moreover, the structure of patent document 1 employ | adopts the method of fixing a PTO axis | shaft cover by the lock mechanism comprised with a spring, a receiving plate, etc. For this reason, the number of parts related to the PTO shaft cover has increased, and there has been a limit in reducing the number of assembly steps and costs.

  Furthermore, in the configuration of Patent Document 1, when an excessive force is applied to the PTO shaft cover at the fixed position from the outside, the lock mechanism may be damaged. For example, because the operator accidentally rides on the PTO shaft cover at the fixed position, the lock pin configured to receive the weight of the operator via the PTO shaft cover cannot withstand the load. Sometimes it would be bent. When the lock pin is bent, the engagement between the engagement hole and the lock pin cannot be released, and the PTO shaft cover cannot be moved from the fixed position.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a simple configuration in which the PTO shaft cover provided in the tractor can be easily fixed at the protective position or the open position and has a small number of parts. There is.

Means and effects for solving the problems

  The problems to be solved by the present invention are as described above. Next, means for solving the problems and the effects thereof will be described.

  According to the viewpoint of this invention, the tractor comprised as follows is provided. That is, the tractor includes a main body, an engine, a transmission case, a PTO shaft, a PTO shaft cover, and a fixing mechanism. The engine is disposed in the main body. The mission case is disposed on the main body. The PTO shaft protrudes from the transmission case to transmit the driving force of the engine to a work machine that is detachably connected to the main body. The PTO shaft cover is configured to be movable with respect to the mission case. The fixing mechanism can fix the PTO shaft cover at an open position where at least a part of the PTO shaft is exposed and a protective position where the PTO shaft is protected from being connected to the work machine. The fixing mechanism has one or a plurality of convex portions or concave portions arranged on the PTO shaft cover, and has a concave portion or convex portion arranged on the mission case side so as to correspond to the convex portions or the concave portions. Multiple or one. Moreover, the part in which the said convex part or the said recessed part is arrange | positioned is comprised so that elastic deformation is possible. And the said PTO shaft cover is fixed by fitting the said convex part in the said recessed part using an elastic force in the said open position or the said protection position.

  Accordingly, the PTO shaft cover can be fixed at the open position or the protective position by a simple operation of fitting the convex portion into the concave portion. Therefore, it is possible to efficiently perform the operation of moving the PTO shaft cover to the open position and connecting the work machine to the PTO shaft. In addition, since the fixing mechanism for fixing the PTO shaft cover in the open position can be realized with a simple configuration of convex portions and concave portions, it is possible to reduce the number of parts and contribute to the reduction of manufacturing cost and the efficiency of assembly work.

  The tractor is preferably configured as follows. That is, the PTO shaft cover has a bent portion formed by bending a part thereof. On the mission case side, a stopper that contacts the bent portion is arranged on at least one side of the movable stroke of the PTO shaft cover.

  As a result, a large force is applied to the PTO shaft cover so that the fitting between the convex portion and the concave portion is disengaged, and even if the PTO shaft cover attempts to move out of the movable stroke, the movement is performed by the stopper. Can be regulated. Accordingly, it is possible to effectively prevent a situation in which the PTO shaft cover comes into contact with the PTO shaft due to movement beyond the movable stroke, or the PTO shaft cover cannot be returned to the protection position or the open position.

  In the tractor, the PTO shaft cover is preferably formed with a notch so as to be adjacent to a portion where the convex portion or the concave portion is disposed.

  As a result, the force required to elastically deform the PTO shaft cover by intentionally reducing the rigidity of the portion where the convex portion or the concave portion of the PTO shaft cover is disposed by a simple method of forming a notch. Can be reduced. Therefore, the workability at the time of fitting the convex part to the concave part can be improved efficiently, and the connecting work can be performed more smoothly.

The side view of the tractor concerning one embodiment of the present invention. The rear view of the tractor of this embodiment. The expansion perspective view which showed the mode of the PTO axis | shaft and the PTO axis | shaft cover. The expanded side view which showed the PTO shaft cover of a protection position and an open position. The disassembled perspective view which showed the mode of the PTO shaft cover attached to a transmission case via an intermediate member. The expansion perspective view which showed a mode that the bending part is contacting the intermediate member as a stopper. The perspective view which showed the mode when the PTO shaft cover of a modification is in a protection position. The perspective view which showed the mode when the PTO shaft cover of a modification is in an open position. The schematic diagram which showed the mode of the fixing mechanism with which the PTO shaft cover of a modification is provided. The schematic diagram which showed the mode of the rotation mechanism of the PTO shaft cover with which the tractor which concerns on one Embodiment of the technical idea grasped | ascertained from the structure of this embodiment.

  Next, an embodiment of the invention will be described. FIG. 1 is a side view of a tractor 10 according to an embodiment of the present invention. FIG. 2 is a rear view of the tractor 10 of the present embodiment. FIG. 3 is an enlarged perspective view showing a state of the PTO shaft 60 and the PTO shaft cover 62. In the following description, “left side”, “right side”, and the like simply mean the left side and the right side in the direction in which the tractor 10 moves forward. The term “front side” simply refers to the direction in which the tractor 10 advances, and the term “rear side” refers to the direction opposite to the direction in which the tractor 10 advances. .

  The tractor 10 of the present embodiment is a work vehicle for agricultural work, and is equipped with various attachments (working machines) such as a loader, a plow, and a box scraper as necessary, and performs various operations using the attachments. It is configured to be able to.

  As shown in FIG. 1, a front wheel 14 and a rear wheel 15 are disposed before and after the tractor 10. A bonnet 20 is disposed in front of the vehicle body of the tractor 10. An engine 19 or the like is accommodated in the bonnet 20. The engine 19 is supported on the body frame of the tractor 10 directly or via a vibration isolation member.

  Behind the bonnet 20 is a cockpit 16 for an operator to board. In the cockpit 16, operating tools 12 such as a handle and a lever for performing various operations are arranged. An operator of the tractor 10 performs a traveling operation of the tractor 10, an attachment operation, and the like via the operation tool 12.

  As shown in FIGS. 1 and 2, a mission case 21 is disposed at the rear of the vehicle body of the tractor 10. As shown in FIG. 2, a rear axle case 17 is provided so as to protrude in the vehicle body width direction from the left and right of the transmission case 21, and the rear axle that supports the rear wheel 15 is supported from the left and right rear axle cases 17. Is protruding.

  As shown in FIGS. 2 and 3, the PTO shaft 60 protrudes rearward from the rear end portion of the mission case 21. The PTO shaft 60 is for transmitting the power of the engine 19 to an attachment connected to the tractor 10. A power transmission mechanism (not shown in the drawings) such as a gear is disposed inside the mission case 21, and the power of the engine 19 is transmitted to the PTO shaft 60 by this power transmission mechanism. The aforementioned attachment can obtain the driving force of the engine 19 by being connected to the PTO shaft 60.

  Further, as shown in FIG. 3, a draw bar hitch 65 extending rearward of the tractor 10 is disposed at the rear end portion of the mission case 21. The drawbar hitch 65 is used when the tractor 10 pulls various tow-type working machines and trailers.

  The draw bar hitch 65 of this embodiment includes a connecting portion 71, a bar member 72, a bar support portion 73, a pivot shaft 74, and a draw bar hitch attachment portion 85. The connecting portion 71 is for connecting various towed working machines or trailers. The bar member 72 is disposed at the rear portion of the tractor 10 with its longitudinal direction directed in the front-rear direction, and the connecting portion 71 is fixed to the upper surface of the rear end portion. The bar member 72 is fixed to the bar support portion 73 via a pivot shaft 74. Drawbar hitch attachment portions 85 are fixed to the left and right sides of the bar support portion 73. The draw bar hitch 65 is arranged so that the draw bar hitch mounting portion 85 is positioned on the side of the mission case 21. Then, the draw bar hitch 65 is fixed to the mission case 21 by fixing the left and right draw bar hitch mounting portions 85 to the left and right side walls of the mission case 21 with bolts 93. The tractor 10 can pull the trailer by, for example, connecting a trailer to the connecting portion 71.

  A PTO shaft cover 62 is disposed at the rear end of the mission case 21. The PTO shaft cover 62 is for protecting the PTO shaft 60 and is attached to the draw bar hitch attachment portion 85 via an intermediate member 66.

  The configuration of the PTO shaft cover 62 will be described in detail. FIG. 4A is an enlarged side view showing the state of the PTO shaft cover 62 in the protected position. FIG. 4B is an enlarged side view showing the state of the PTO shaft cover 62 in the open position. FIG. 5 is an exploded perspective view showing a state of the PTO shaft cover 62 attached to the mission case 21 via the intermediate member 66. FIG. 6A is an enlarged perspective view showing a state in which the bent portion 70 is in contact with the intermediate member 66 as a stopper from the front side. FIG. 6B is an enlarged perspective view showing a state in which the bent portion 70 is in contact with the intermediate member 66 as a stopper from the back side.

  As shown in FIGS. 4 (a) and 4 (b), the PTO shaft cover 62 of the present embodiment rotates between a protected position when the attachment is not attached and an open position when the attachment is attached. It is configured to be movable. The PTO shaft cover 62 includes a main body portion 81, a mounting portion 82, a rotating shaft 80, and a bent portion 70. In addition, among the said structure, the main-body part 81, the attaching part 82, and the bending part 70 are integrally formed with the metal or resin.

  The main body 81 is formed so as to have a gate shape in the rear view, and can cover the upper and left and right directions of the PTO shaft 60 when the PTO shaft cover 62 is in the protection position. . Note that, even when the PTO shaft cover 62 is in the protected position, the lower side and the rear side of the PTO shaft 60 of the present embodiment are exposed to the outside.

  As shown in FIG. 5, the attachment portions 82 are disposed on both the left and right sides of the PTO shaft cover 62. The attachment portion 82 extends to the front side (front side) while being inclined downward in a side view. An insertion hole 91 for inserting the rotation shaft 80 is formed in the upper portion of the attachment portion 82. Further, a cover-side convex portion 76 is disposed at the front end portion of the attachment portion 82 and in front of and below the insertion hole 91. The cover-side convex portions 76 are respectively formed inside the attachment portions 82 arranged on the left and right sides, and the left and right cover-side convex portions 76 are opposed to each other. The details of the cover-side convex portion 76 will be described later.

  Further, the attachment portion 82 is configured to be elastically deformable with an appropriate metal or resin. A notch 79 is formed adjacent to the cover-side convex portion 76 of the mounting portion 82 so as to be adjacent thereto. The cutout 79 is formed in the lower portion of the attachment portion 82 so as to cut from the lower side on the front side to the upper side on the rear side in a side view. This notch 79 creates a gap between a part of the mounting portion 82 and the main body 81, and the rigidity of the portion where the cover-side convex portion 76 is disposed (portion formed in an arm shape) is low. It has become.

  As shown in FIG. 5, the intermediate member 66 is formed so as to have a gate shape when viewed from the back, and is disposed so as to straddle the draw bar hitch 65. More specifically, the intermediate member 66 is fixed to the draw bar hitch 65 by fixing the side wall portions thereof to the draw bar hitch mounting portions 85 on both the left and right sides with bolts 94. Fixing holes 92 for fixing the rotation shaft 80 are respectively formed on the left and right sides of the intermediate member 66. The PTO shaft cover 62 is supported through a rotation shaft 80 in a fixing hole 92 of an intermediate member 66 disposed inside the mounting portion 82. The rotation shaft 80 of the present embodiment is constituted by a bolt or the like, and is inserted through the fixing hole 92 of the intermediate member 66 in a state of passing through the attachment portion 82 (insertion hole 91). Then, the distal end portion of the rotation shaft 80 is protruded from the fixing hole 92, and the distal end portion is fixed with a nut 95.

  As shown in FIG. 5, the bent portions 70 are arranged on both the left and right sides of the PTO shaft cover 62. More specifically, the bent portion 70 is formed so as to be bent inward from the front end surface of the main body portion 81, and is positioned below the attachment portion 82.

  Further, as shown in FIG. 5, the bent portion 70 is configured to have an elongated flat surface portion 70 a in the vertical direction. The flat portion 70a of the bent portion 70 faces the part of the rear side end surface of the intermediate member 66 with almost no gap at the protected position of the PTO shaft cover 62 (see FIG. 4A). Further, the flat portion 70a of the bent portion 70 faces the part of the rear side end face of the draw bar hitch attachment portion 85 with almost no gap at the protected position of the PTO shaft cover 62 (see FIG. 6). .

  With this configuration, even if the PTO shaft cover 62 tries to rotate to the front side (forward) from the protection position, the bent portion 70 comes into contact with the intermediate member 66 and the draw bar hitch mounting portion 85, and the PTO shaft cover 62 is further moved. It becomes impossible to turn forward. In other words, the intermediate member 66 and the draw bar hitch mounting portion 85 function as a stopper that restricts the movement of the PTO shaft cover 62 from the rotation stroke (on one side of the rotation stroke).

  By configuring in this way, for example, when the operator accidentally sets the PTO shaft cover 62 in the protected position as a scaffold during maintenance of the tractor 10, the PTO shaft cover 62 depends on the weight of the operator. Even if a force to rotate the front side of the protection position acts and a force sufficient to release the fitting between the cover-side convex portion 76 and the first concave portion 77 is applied to the PTO shaft cover 62 The bent portion 70 (PTO shaft cover 62) is received by the intermediate member 66 and the draw bar hitch mounting portion 85. Thus, the PTO shaft cover 62 of the present embodiment is stably held at the holding position without moving forward from the protected position even when a large force is applied as described above.

  Next, a fixing mechanism for fixing the PTO shaft cover 62 at the protection position or the open position will be described. The fixing mechanism of the present embodiment includes the above-described cover-side convex portion 76 formed on the PTO shaft cover 62, and the first concave portion 77 and the second concave portion 78 formed on the intermediate member 66.

  The cover-side convex portion 76 is formed inside the attachment portion 82 (arm-shaped portion) and protrudes so as to face the side surface of the intermediate member 66. The cover-side convex portion 76 is configured such that the protruding amount is larger than the gap formed between the PTO shaft cover 62 and the intermediate member 66. The cover side convex portion 76 of the present embodiment is formed integrally with the attachment portion 82.

  On the other hand, the first concave portion 77 and the second concave portion 78 formed on the side surface of the intermediate member 66 are both constituted by penetrating holes. The first concave portion 77 is for fixing the PTO shaft cover 62 at the protection position by elastically deforming the attachment portion 82 and fitting the cover side convex portion 76. The second recess 78 is for fixing the PTO shaft cover 62 at the open position by elastically deforming the mounting portion 82 and fitting the cover-side convex portion 76.

  As described above, the portion of the attachment portion 82 where the cover-side convex portion 76 is disposed is easily elastically deformed by the notch 79. Therefore, the operator can perform a fitting operation (or a fitting releasing operation) between the cover-side convex portion 76 and the first concave portion 77 or the second concave portion 78 with a slight force. .

  The first recess 77 and the second recess 78 are arranged along an arcuate rotation locus (movement locus) drawn by the cover-side protrusion 76 when the PTO shaft cover 62 is rotated. In the present embodiment, the second recess 78 is positioned lower than the first recess 77 in order to follow the rotation locus (see FIG. 4).

  The cover-side convex portion 76 is formed on each of the left and right attachment portions 82. Further, the first concave portion 77 and the second concave portion 78 are also formed on the left and right sides of the intermediate member 66 so as to correspond to the cover side convex portion 76. As described above, the fixing mechanism of the present embodiment is configured to include the cover-side convex portion 76, the first concave portion 77, and the second concave portion 78 in pairs, and at two locations in the left-right direction. The PTO shaft cover 62 can be stably held.

  With the above configuration, the PTO shaft cover 62 can be fixed at the protection position or the open position. As shown in FIGS. 3 and 4 (a), the PTO shaft cover 62 in the protected position is in a state of covering the upper and left and right directions of the PTO shaft 60 in a state where no attachment is attached. On the other hand, as shown in FIG. 4B, the PTO shaft cover 62 in the open position is in a state where the base side of the PTO shaft 60 is exposed in a side view. Thus, when the PTO shaft cover 62 is in the open position, a hand can be inserted from the side of the tractor 10 to the base side of the PTO shaft 60, so that the attachment connecting mechanism and the PTO shaft 60 can be connected. Can be performed smoothly.

  As described above, the tractor 10 of the present embodiment is configured as follows. That is, the tractor 10 includes a main body, an engine 19, a mission case 21, a PTO shaft 60, a PTO shaft cover 62, and a fixing mechanism. The engine 19 is disposed in the tractor 10 main body. The mission case 21 is disposed on the tractor 10 body. The PTO shaft 60 protrudes from the mission case 21 to transmit the driving force of the engine 19 to an attachment (work machine) that is detachably connected to the tractor 10 body. The PTO shaft cover 62 is configured to be movable with respect to the mission case 21. The fixing mechanism can fix the PTO shaft cover 62 at an open position where at least a part of the PTO shaft 60 is exposed and a protective position where the PTO shaft 60 in a state where the connection with the attachment is released is protected. The fixing mechanism has a cover-side convex portion 76 disposed on the PTO shaft cover 62, and a first concave portion 77 and a second concave portion 78 disposed on the mission case 21 side so as to correspond to the cover-side convex portion 76. Have In addition, the portion of the PTO shaft cover 62 where the cover-side convex portion 76 is disposed is configured to be elastically deformable. Then, the fixing mechanism fixes the PTO shaft cover 62 at the protected position by fitting the cover-side convex portion 76 to the first concave portion 77 using the elastic force of the PTO shaft cover 62. Further, the fixing mechanism fixes the PTO shaft cover 62 in the open position by fitting the cover side convex portion 76 to the second concave portion 78 using the elastic force of the PTO shaft cover 62.

  Accordingly, the PTO shaft cover 62 can be fixed at the open position or the protected position by a simple operation of fitting the cover side convex portion 76 to the first concave portion 77 or the second concave portion 78. Therefore, the operation of connecting the attachment to the PTO shaft 60 by moving the PTO shaft cover 62 to the open position can be performed efficiently. In addition, since the fixing mechanism for fixing the PTO shaft cover 62 in the open position can be realized with a simple configuration of convex portions and concave portions, it is possible to reduce the number of parts and contribute to the reduction of manufacturing cost and the efficiency of assembly work.

  Moreover, the tractor 10 of this embodiment is comprised as follows. That is, the PTO shaft cover 62 has a bent portion 70 formed by bending a part thereof. An intermediate member 66 that contacts the bent portion 70 on one side of the movable stroke of the PTO shaft cover 62 is disposed on the mission case 21 side.

  As a result, a large force is applied to the PTO shaft cover 62 that causes the cover-side convex portion 76 and the first concave portion 77 to be disengaged, and the PTO shaft cover 62 tries to move out of the movable stroke. Even if it exists, the movement can be regulated by the intermediate member 66. Accordingly, it is possible to effectively prevent a situation in which the PTO shaft cover 62 comes into contact with the PTO shaft 60 due to the movement exceeding the movable stroke or the PTO shaft cover 62 cannot be returned to the protection position.

  Further, in the tractor 10 of the present embodiment, the PTO shaft cover 62 is formed with a notch 79 so as to be adjacent to a portion where the cover-side convex portion 76 is disposed.

  Accordingly, the PTO shaft cover 62 is elastically deformed by intentionally reducing the rigidity of the portion where the cover-side convex portion 76 of the PTO shaft cover 62 is arranged by a simple method of forming the notch 79. It is possible to reduce the necessary force. Therefore, the workability at the time of fitting the cover side convex portion 76 to the first concave portion 77 or the second concave portion 78 can be improved efficiently, and the connecting operation can be performed more smoothly.

  Although the embodiment of the present invention has been described above, the above configuration can be further modified as follows.

  The intermediate member 66 of the present embodiment is configured to restrict the movement of the PTO shaft cover 62 only on one side of the rotation stroke, but this configuration can be appropriately changed according to circumstances. Next, a modified example in which the intermediate member 166 is configured to restrict the movement of the PTO shaft cover 62 on both sides of the rotation stroke will be described. FIG. 7 is a perspective view showing a state in which the modified PTO shaft cover 62 is in the protected position. FIG. 8 is a perspective view showing a state in which the modified PTO shaft cover 62 is in the open position. In the modification, the same or similar configurations as those of the present embodiment may be denoted by the same reference numerals in the drawings, and the description thereof may be omitted.

  The modified intermediate member 166 has a protruding portion 111 that protrudes rearward. The protrusion 111 is for restricting the movement of the PTO shaft cover 62 further upward than the open position. As shown in FIG. 7, the protruding portion 111 is formed in a rectangular shape that protrudes from the front side to the back side, and is formed integrally with the intermediate member 166. As shown in FIG. 8, the protruding portion 111 has an end surface 111 a that contacts the upper end surface 70 b of the bent portion 70 at the end of the opening side (upward) rotation stroke, thereby causing the PTO upward from the opening position. The movement of the shaft cover 62 is restricted.

  Thereby, even if the PTO shaft cover 62 tries to move further upward from the open position, the upper end surface 70b of the bent portion 70 comes into contact with the end surface 111a of the protruding portion 111, and its movement is restricted. It is possible to prevent the fitting of the two concave portions 78 and the cover side convex portion 76 of the attachment portion 82 from being disengaged. Also, the intermediate member 166 of this modification is configured to function also as a stopper that restricts the movement of the PTO shaft cover 62 that is about to move further to the front side (front) than the protection position, as in this embodiment. Has been. That is, in the present modification, the intermediate member 166 is configured to function as a stopper that restricts the movement of the PTO shaft cover 62 on both sides of the movable stroke of the PTO shaft cover 62.

  In the present embodiment, the cover-side convex portion 76 is integrally formed with the mounting portion 82 of the PTO shaft cover 62, but this configuration can be changed as appropriate according to circumstances. Next, a modified example of the convex portion formed on the PTO shaft cover will be described with reference to FIG. FIG. 9A is an enlarged side view schematically showing the vicinity of the attachment portion 82 included in the PTO shaft cover 262 of this modification. FIG. 9B is a partial front sectional view of the PTO shaft cover 262 schematically showing the state of the pressing mechanism 276 constituting the convex portion of this modification.

  As shown in FIG. 9A, a pressing mechanism (detent mechanism) 276 that functions as a cover-side convex portion is attached to the PTO shaft cover 262. As illustrated in FIG. 9B, the pressing mechanism 276 includes a case 281, a push bolt 282, a coil spring (elastic member) 283, and a ball 284. The pressing mechanism 276 is attached to both the left and right sides of the PTO shaft cover 262.

  The case 281 is configured in a cylindrical shape, and is disposed on the attachment portion 82 of the PTO shaft cover 262. The push bolt 282 is screwed into a screw groove 281 a formed on the inner wall of the case 281. The position of the push bolt 282 is set so that the tip portion thereof contacts one side of the coil spring 283. A ball 284 is disposed on the other side of the coil spring 283. The ball 284 is biased by a coil spring 283 so as to protrude from the mounting portion 82 to the intermediate member 66 side. That is, it can be said that the ball 284 of the pressing mechanism 276 functions as a convex portion protruding from the side surface of the mounting portion 82 of the PTO shaft cover 262 toward the intermediate member 66.

  A first recess 277 and a second recess 278 are formed in a recessed shape on the outer side surface of the intermediate member 66. The first recess 277 and the second recess 278 are disposed at the same positions as the first recess 77 and the second recess 78 of the present embodiment. In addition, you may comprise the 1st recessed part 277 and the 2nd recessed part 278 as a through-hole similarly to this embodiment.

  When fixing the PTO shaft cover 262 in the protected position, the PTO shaft cover 262 is rotated to a position where the ball 284 of the pressing mechanism 276 is fitted into the first recess 277. Further, when the PTO shaft cover 262 is fixed in the open position, the PTO shaft cover 262 is rotated to a position where the ball 284 of the pressing mechanism 276 is fitted into the second recess 278. Thus, also in the modified PTO shaft cover 262, the pressing mechanism 276 as the convex portion, the first concave portion 277, and the second concave portion 278 can be fixed at the protection position and the open position.

  The PTO shaft cover 262 of this modification is configured to fit the tip portion of the ball 284 with the first recess 277 or the second recess 278 using elastic deformation of the coil spring 283. With this configuration, the PTO shaft cover 262 can be formed of a member that cannot be elastically deformed. Further, the holding force for holding the PTO shaft cover 262 at the fixed position can be adjusted by changing the position of the push bolt 282 to adjust the urging force to the ball 284.

  Further, in this embodiment and the modification, the PTO shaft cover 62 is fixed to the transmission case 21 side via the intermediate member 66 and the draw bar hitch 65, but this configuration can be appropriately changed according to circumstances. . For example, the intermediate member 66 may be omitted, and the PTO shaft cover 62 may be rotatably attached to the draw bar hitch 65. In this case, the first recess 77 and the second recess 78 are preferably formed in the draw bar hitch 65. Further, the PTO shaft cover 62 may be directly attached to the mission case 21. In this case, the first recess 77 and the second recess 78 are preferably formed in the mission case 21.

  In the fixing mechanism of the present embodiment and the modified example, the cover-side convex portion 76 is formed on the PTO shaft cover 62, and the first concave portion 77 and the second concave portion 78 are formed on the mission case 21 side (intermediate member 66). Although it is a structure, this invention is not necessarily limited to this structure. For example, a concave portion can be formed in the PTO shaft cover, and the convex portion can be formed on the mission case side. It is also possible to arrange two convex portions on the PTO shaft cover and one concave portion on the intermediate member. Thus, the convex part and the concave part only have to be configured to have at least a combination that fits at the protective position and a combination that fits at the open position. Can be changed as appropriate.

  Further, in the present embodiment and the modification, the PTO shaft cover 62 is configured to be rotatable with respect to the mission case 21, but if the structure can be moved with respect to the mission case, this configuration is appropriately set according to circumstances. Can be changed. For example, the PTO shaft cover can be configured to be slidable in the vertical direction with respect to the mission case 21.

  In addition, at least the technical idea comprised as follows can be grasped | ascertained from embodiment described above and its modification. That is, in order to transmit the driving force of the engine to a main body, an engine disposed in the main body, a transmission case disposed in the main body, and a work machine detachably connected to the main body, the transmission case A PTO shaft protruding outward from the transmission case, a PTO shaft cover rotatable with respect to the transmission case, and an elastic member for imparting resistance to rotational movement of the PTO shaft cover in order to fix the position of the PTO shaft cover A tractor characterized by that.

  Next, the configuration of the PTO shaft cover 62 included in the tractor according to an embodiment of this technical idea will be described with reference to FIG. FIG. 10A is an enlarged side view schematically showing the vicinity of the attachment portion 382 of the modified PTO shaft cover 362. FIG. 10B is a partial front sectional view of the PTO shaft cover 262 schematically showing the vicinity of the rotating mechanism 380 of this modification.

  In the example referred to in FIG. 10, as shown in FIG. 10A, only the rotation mechanism 380 is disposed in the mounting portion 382, and unlike the embodiment of the present invention, it is not necessary to have a convex portion and a concave portion. . As shown in FIG. 10B, the rotation mechanism 380 of this modification includes a support bolt (rotating shaft) 311, a disc spring (elastic member) 312, a collar 313, and a nut (rotating shaft fixing member). 314. The support bolt 311 is fixed to the intermediate member 66 by a nut 314. A PTO shaft cover 362 is rotatably supported on the shaft portion of the support bolt 311. The disc spring 312 is supported in an inserted state by the support bolt 311 so that one side thereof contacts the support bolt 311 and the other side contacts the PTO shaft cover 362. By this disc spring 312, the PTO shaft cover 362 is urged toward the intermediate member 66 side. The collar 313 is disposed between the support bolt 311 and the PTO shaft cover 362 and is used for setting the tightening torque of the support bolt 311.

  In this embodiment, a frictional force is generated between the PTO shaft cover 362 and the intermediate member 66 by the biasing force of the disc spring 312, and the PTO shaft cover 362 can be held in a stationary state by this frictional force. By this friction holding mechanism, the operator can fix the PTO shaft cover 362 while moving it to a desired position.

10 Tractor 19 Engine 21 Mission case 60 PTO shaft 62 PTO shaft cover 66 Intermediate member (stopper)
70 Bent part 76 Cover side convex part (convex part)
77 First recess (recess)
78 Second recess (recess)
79 Notch

Claims (3)

The body,
An engine disposed in the body;
A mission case arranged in the main body;
In order to transmit the driving force of the engine to a work machine that is detachably connected to the main body, a PTO shaft that protrudes outside from the transmission case;
A PTO shaft cover movable with respect to the mission case;
A fixing mechanism capable of fixing the PTO shaft cover at an open position at which at least a part of the PTO shaft is exposed and a protective position for protecting the PTO shaft in a state in which the connection with the work machine is released;
With
The fixing mechanism is
While having one or a plurality of convex portions or concave portions arranged on the PTO shaft cover, and having one or more concave portions or convex portions arranged on the mission case side so as to correspond to the convex portions or the concave portions,
The portion where the convex portion or the concave portion is arranged is configured to be elastically deformable,
The tractor characterized in that the PTO shaft cover is fixed by fitting the convex portion to the concave portion using elastic force at the open position or the protective position. The tractor according to claim 1,
The PTO shaft cover has a bent portion formed by bending a part thereof,
A tractor characterized in that a stopper that contacts the bent portion is arranged on at least one side of the movable stroke of the PTO shaft cover on the mission case side. The tractor according to claim 1 or 2,
The tractor according to claim 1, wherein the PTO shaft cover is formed with a notch portion adjacent to a portion where the convex portion or the concave portion is disposed.

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