JP2012140104A - Turn signal operating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a turn signal operating device whose operability is improved.SOLUTION: The turn signal operating device includes: a cancel cam 10 externally fitted to a steering shaft 11, and having a cancel projection part 103 projected in an outer circumferential direction from a shaft center of the steering shaft 11; an operation lever 20 for operating a turn signal switch for indicating a traveling direction of a vehicle 1; an adjustment retention mechanism 30 mounted to the operation lever 20 and retaining the operation lever 20 to a middle position N, a right turn direction indication position R, or a left turn direction indication position L; and a claw member 40 which is mounted to the adjustment retention mechanism 30, and projects to contact the cancel projection part 103 when held at the direction indication positions R, L. An insertion hole 11a vertical to the shaft center direction is formed in the steering shaft 11. A long hole 104 longer than the diameter of the insertion hole 11a is formed in the outer circumferential direction in the cancel cam 10. A transmission shaft 50 is inserted in the insertion hole 11a and the long hole 104.

Description

  The present invention relates to a turn signal operation device, and more particularly, to a cancel cam technique that is fitted around a steering shaft to cancel operation holding of an operation lever.

  Conventionally, in a traveling vehicle, an operation lever for a direction indicator (turn signal) is arranged near the steering shaft, and the switch is turned “ON” by operating the operation lever from a neutral position to a right turn or left turn direction indication position. As shown, the right or left turn signal attached to the traveling vehicle blinks. In such a traveling vehicle, a turn signal switch canceling structure for stopping blinking of the turn signal even if the operator does not perform a special operation after the traveling vehicle turns right or left is configured.

  For example, in the cancel structure of the turn signal switch shown in Patent Document 1, a turn signal switch (a combination of the adjustment holding mechanism and the switch) that holds the operation position of the operation lever is disposed in the vicinity of the steering shaft. The operation position is supported by a turn signal switch via a movable board (bracket) while being supported. The adjustment holding mechanism on the steering shaft side has a cancel cam (claw member) for holding the operation position of the operation lever from the neutral position (neutral position) to the right turn direction or the left turn direction indicating position by moving the adjustment holding mechanism on the steering shaft side. ) Is arranged. On the other hand, a member (cancellation cam) having a cancel pin (cancellation protrusion) is externally fitted to the steering shaft, and the cancel pin is formed to protrude outward from the steering shaft. With this configuration, when a steering operation in a direction opposite to the direction indicated by the operation lever is performed, the claw member is moved from the holding position to the free position, and the operation lever is turned right or left by the adjustment holding mechanism. The turning of the turn signal is terminated by releasing the left turn direction indicating position and returning the operation lever to the neutral position.

In the cancel structure of the turn signal switch having such a configuration, when the cancel protrusion of the cancel cam is in the lock position (holding position) of the claw member, even if the operation lever is operated to the right turn direction or the left turn direction instruction position, There are cases where the claw member cannot move to the locked position in contact with the cancel protrusion.
Further, after the traveling vehicle turns right or left, the operation lever does not readily return to the neutral position, and it may be delayed to stop blinking the turn signal.

JP 2001-10406 A

  The present invention has been made in view of the above situation, and an object of the present invention is to provide a turn signal operation device with improved operability.

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

  In other words, in claim 1, a steering shaft to which a steering handle is attached, a cancel cam that is fitted on the steering shaft and has a cancel protrusion protruding outward from the axis of the steering shaft, and traveling of the vehicle An operation lever that operates a turn signal switch for direction indication, an adjustment holding mechanism that is attached to the operation lever and holds the operation lever at a neutral position, a right turn direction indication position, or a left turn direction indication position, and the adjustment holding A turn signal operating device that is attached to the mechanism and includes a claw member that protrudes so as to come into contact with the canceling protrusion when being held at a right turn direction indicating position or a left turn direction indicating position, An insertion hole perpendicular to the axial direction is formed, and the cancel cam has Long elongated hole than the diameter of the serial insertion holes are formed in the outer peripheral direction, the transmission shaft in the insertion hole and the elongated hole is intended to be inserted.

  According to a second aspect of the present invention, the cancel protrusion is formed at three or four locations on the outer periphery of the cancel cam at the same angle in the radial direction from the axis of the cancel cam.

  According to a third aspect of the present invention, the tip of the canceling protrusion is formed in a curved shape.

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

  In claim 1, when the operation lever is operated from the neutral position to the right turn direction indicating position or the left turn direction indicating position, even if the claw member comes into contact with the cancel protrusion, the transmission shaft and the end of the long hole are not The cancel cam can be rotated until it comes into contact, in other words, the transmission shaft is rotated so as to escape within the elongated hole, and the claw member and the cancel projection are moved without being blocked (displaced). The control lever can be held at the right turn direction indicating position or the left turn direction indicating position by the adjustment holding mechanism. That is, the adjustment holding mechanism can avoid the operation lever from returning to the neutral position without being held at the right turn direction instruction position or the left turn direction instruction position, and the operability of the operation lever is improved.

  In the second aspect, in addition to the effect of the first aspect, the contact frequency between the claw member and the canceling protrusion can be increased during the turning operation, and the operation lever at the right turn direction indication position or the left turn direction indication position is provided. The timing to return to the neutral position can be advanced. Therefore, it is possible to prevent unnecessary turn signals from blinking.

  According to the third aspect of the present invention, when the claw member comes into contact with the cancel projection, the tip of the cancel projection is formed in a curved surface, so that the force at the time of movement of the claw member is released well, and the claw member moves. As a result, the operating lever can be held at the right turn direction indication position or the left turn direction indication position by the adjustment holding mechanism. That is, the operation lever can be prevented from returning to the neutral position without being held at the right turn direction instruction position or the left turn direction instruction position, and the operability of the operation lever is improved.

The right view of the tractor which concerns on one Embodiment of this invention. The rear view which similarly shows the structure around the operation handle. FIG. 2 is a partial cross-sectional view in the direction of arrow A in FIG. 1 showing the configuration of the cancel structure. The figure which shows the structure of the cancellation structure in which an operation lever is in a neutral position. The figure which shows the structure of the cancellation structure in which an operation lever is a right turn direction instruction | indication position. The perspective view which shows the state by which the cancellation cam was externally fitted by the steering shaft. The figure which shows a cancellation cam and a steering shaft. (A) The top view seen from the axial center direction of the cancellation cam. (B) C direction arrow directional view in (a) of FIG. (C) BB sectional drawing in (a) of FIG. (D) The figure which shows the state which removed the transmission shaft from the state of (c) of FIG. The figure which shows the state of the cancellation structure in the state which the steering is turning in the same direction as the right turn direction instruction | indication position. The figure which shows the state of the cancellation structure in the state which the steering is turning in the direction opposite to the right turn direction instruction | indication position. The figure which shows the state which has a cancellation protrusion in the position of the nail | claw member of a locked state. The figure which shows the state of the transmission shaft and long hole after avoiding. The figure which shows the state which a cancellation | release protrusion and a claw member try to mesh | engage in the state with an operation lever in a right turn direction instruction | indication position. The figure which shows the structure which has arrange | positioned the nail | claw member two places with respect to the adjustment holding | maintenance mechanism. The figure which shows the positional relationship of the transmission shaft and cancellation protrusion which concern on another embodiment of this invention. (A) The top view seen from the axial center direction of the cancellation cam. (B) D direction arrow view in (a) of FIG.

Below, the tractor 1 which is one Embodiment (1st embodiment) of the traveling vehicle which concerns on this invention is demonstrated.
Note that the traveling vehicle according to the present invention is not limited to the tractor 1 that is the working vehicle according to the present embodiment, and is widely used as other working vehicles such as agricultural vehicles, construction vehicles, and industrial vehicles, and ordinary passenger cars. It can be applied in general.
Further, the direction of the arrow F in the figure is defined as the front direction, and the entire configuration of the tractor 1 will be described by determining the left and right and the rear toward the front.

  As shown in FIG. 1, in the tractor 1, the body frame 2 is arranged with the longitudinal direction as the front-rear direction, and is supported by a pair of left and right front wheels 4, 4 via a front axle at the front portion thereof, It is supported by a pair of left and right rear wheels 5 and 5 via a rear axle. An engine 3 is provided at the front of the body frame 2 and is covered with a bonnet 6. A power transmission mechanism is provided at the rear of the body frame 2.

  Then, after the power of the engine 3 is shifted by the power transmission mechanism, it can be transmitted to the pair of left and right front wheels 4 and 4 via the front axle, and transmitted to the pair of left and right rear wheels 5 and 5 via the rear axle. It is possible. When the power of the engine 3 is transmitted, the pair of left and right front wheels 4 and 4 and the pair of left and right rear wheels 5 and 5 are rotationally driven, and the tractor 1 travels.

  Then, after the power of the engine 3 is shifted by the power transmission mechanism, it can be transmitted to a working machine such as a tillage device (not shown) attached to the body frame 2. When the power of the engine 3 is transmitted, the working machine is driven.

  A driving operation unit for operating the tractor 1 and performing various operations is provided from the midway part to the rear part of the machine body frame 2 and is covered with the cabin 7. A seat 8 is disposed at a rear portion in the cabin 7, and operation tools such as a main transmission lever and a sub transmission lever are projected from a side portion of the seat 8. A brake pedal, a main clutch pedal, a differential lock pedal, and the like are disposed above the step in front of the seat 8. As shown in FIGS. 1 and 2, a steering column 9 protrudes rearward and upward at a front portion in a cabin 7 behind the bonnet 6, and a steering shaft 11 is supported substantially vertically in the steering column 9. A steering handle 12 is fixed to the upper end of the shaft 11. In the steering column 9, an operation panel is disposed at an upper portion thereof, and an operation lever 20 for instructing a direction, various operation switches, and the like are disposed on a side portion thereof. A pair of left and right turn signals 71, 71, 71, 71 are arranged on the outside of both sides of the front part and the rear part of the cabin 7.

  The steering handle 12 is configured such that the tractor 1 can be steered by changing the steering angle of the pair of left and right front wheels 4 and 4 according to the amount of rotation operation. In addition, the operator can operate the operation lever 20 in advance before steering (right turn or left turn) to blink the right or left turn signals 71 and 71 to indicate the expected course of the tractor 1 to the surroundings. Configured as follows.

  In the following description, a turn signal switch canceling structure (hereinafter simply referred to as “cancelling structure”) that automatically returns the operation lever 20 to the neutral position N after the tractor 1 turns right or left is a well-known configuration. explain. For convenience, the cancellation structure will be described using the up / down / front / back / left / right directions shown in the drawing.

  As shown in FIGS. 3 and 4, the cancel structure is mainly configured by the operation lever 20, the adjustment holding mechanism (detent mechanism) 30, the claw member 40, the cancel cam 10, and the like.

  The operation lever 20 is an operation tool for blinking the right or left turn signals 71 and 71 (see FIG. 1). The operation lever 20 is disposed so as to protrude outward from the upper right portion of the steering column 9. One end of the operation lever 20 inside the steering column 9 is disposed in the adjustment holding mechanism 30. When the operator lever 20 is operated forward or backward by the operator, the axis of the operation lever 20 is positioned at a left turn direction indicating position L or a right turn direction indicating position R indicated by a two-dot chain line in FIG. By doing so, a turn signal switch (not shown) is operated.

  The adjustment holding mechanism 30 is for holding the operation position of the operation lever 20 and for returning the operation lever 20 to the neutral position after the tractor 1 turns right or left.

  The adjustment holding mechanism 30 mainly includes a case 31, a bracket 32, a first biasing member 33, a moderation member 34, a movable member 35, a second biasing member 36, a third biasing member 37, and the like.

  As shown in FIGS. 1, 3, and 4, the case 31 is disposed in the steering column 9 and in the vicinity of the outer periphery of the steering shaft 11 at a predetermined interval. The case 31 is formed to be separable, and further, the lower part of the case 31 is electrically connected to the turn signals 71, 71, 71, 71, and the right side or the left side of the turn signals 71, 71 is connected to the case 31. A turn signal switch (not shown) that enables blinking is arranged. As shown in FIG. 4, moderation grooves formed by alternately forming moderation valley portions 31 a, 31 a, 31 a and moderation mountain portions 31 b, 31 b in the left-right direction are formed on both front and rear inner surfaces of the case 31. The

  The bracket 32 is fixed to one end of the operation lever 20 and supports the operation lever 20 so as to be rotatable with respect to the case 31 of the adjustment holding mechanism 30. The bracket 32 is provided with a fulcrum shaft 32a projecting upward in the axial direction substantially the same as the axial direction of the steering shaft 11. The fulcrum shaft 32a is rotatably supported by the case 31.

  A guide hole is formed on the steering shaft 11 side of the bracket 32. On the steering shaft 11 side of the guide hole, guide valley portions 32b and 32b are formed in parallel in the front-rear direction. Between the guide valley portions 32b and 32b, a guide peak portion 32c protruding toward the operation lever 20 is formed.

  Further, support portions 32d and 32d for supporting a movable member 35 described later are formed at a front and a rear center of the left and right center of the bracket 32 so as to protrude with a predetermined interval. On the left side of the fulcrum shaft 32a at the front and rear center of the bracket 32, a spring receiving portion 32e for supporting one end of a second urging member 36 described later is formed.

  On the front and rear outer surfaces of the bracket 32, arm portions 32f and 32f project from the moderation groove (moderation mountain portion 31b and moderation valley portion 31a), and an opening is formed on the distal end side of the arm portions 32f and 32f. Yes. A first urging member 33 formed of a compression coil spring is accommodated in the opening of the arm portion 32f, and a moderation member 34 is disposed at the distal end of the first urging member 33 on the moderation groove side. Therefore, the moderation member 34 is configured to be in pressure contact with the moderation grooves (the moderation valley portion 31a and the moderation mountain portion 31b) by the urging force of the first urging member 33.

  The movable member 35 is pressed by a claw member 40 which will be described later, and transmits the pressing force of the claw member 40 to the bracket 32. The movable member 35 is formed in a substantially “U” shape that is expanded as the opening side faces the steering shaft 11 side. The inner surface on the expansion side of the movable member 35 is a contact surface 35a. The locking projections 35b and 35b are projected inward from the left and right middle portions of the contact surface 35a. The locking protrusions 35b and 35b are protrusions that restrict the claw member 40 from moving in the direction of the fulcrum shaft 32a when the claw member 40 presses the movable member 35. Further, an engagement portion 35c is formed on the right side of the front and rear side surfaces of the movable member 35 so as to be engageable with the support portions 32d and 32d.

  The second urging member 36 is for pressing the movable member 35 toward the claw member 40 side. The second urging member 36 is constituted by a compression coil spring, and one end thereof is fixed to the side surface of the movable member 35 on the operation lever 20 side. The other end of the second urging member 36 is disposed so as to contact the spring receiving portion 32e.

  The claw member 40 interacts with the adjustment holding mechanism 30 to hold the operation lever 20 at the left turn direction instruction position L or the right turn direction instruction position R, or to set the operation lever 20 to the neutral position N. It is. The claw member 40 is formed so that the contact portion 41, the pressing portion 42, and the guide shaft 43 are integrated. The claw member 40 moves to a “free position” shown in FIG. 4 and a “lock position” shown in FIG. Here, the “free position” is a position of the claw member 40 that displaces the adjustment holding mechanism 30 so that the operation lever 20 is set to the neutral position N. The “lock position” is a position of the claw member 40 that displaces the adjustment holding mechanism 30 so that the operation lever 20 can be held at the left turn direction instruction position L or the right turn direction instruction position R.

  The contact portion 41 is a portion that protrudes toward the steering shaft 11 and engages with the cancel cam 10 (specifically, the cancel protrusions 103, 103, and 103) that rotate together with the steering shaft 11.

  The pressing portion 42 is formed in a substantially circular shape protruding toward the movable member 35, and receives the urging force of the second urging member 36 through the movable member 35 by contacting the abutting surface 35 a of the movable member 35. It is a part which presses the bracket 32.

  The guide shaft 43 is formed at a portion between the contact portion 41 and the pressing portion 42 and is disposed so as to protrude upward and downward so that the axial center direction thereof is substantially the same as the axial center of the steering shaft 11. The guide shaft 43 is slidably supported by a long hole (not shown) on the lower side of the case 31 and a guide hole (guide peak portion 32c, guide valley portions 32b and 32b) of the bracket 32.

  The third urging member 37 is configured by a leaf spring, and both ends thereof are fixed to the case 31 by fixing members 37 a and 37 a disposed on the front and rear inner surfaces of the case 31. The front and rear central portions of the third urging member 37 are fixed to the upper portion of the guide shaft 43.

  Therefore, when the third urging member 37 is engaged with the operation lever 20 side of the contact portion 41 and the guide shaft 43, the claw member 40 is urged toward the steering shaft 11 side. Further, the claw member 40 is urged toward the steering shaft 11 when the second urging member 36 presses the pressing portion 42 via the movable member 35. Therefore, the guide shaft 43 of the claw member 40 is locked to the guide peak portion 32c (or the guide valley portions 32b and 32b) and supported on the inclined surface thereof so as to be slidable.

  The cancel cam 10 shown in FIGS. 4 and 6 is for releasing the holding state of the adjustment holding mechanism 30 by contacting the claw member 40. As shown in FIGS. 3 and 6, the cancel cam 10 is fitted on the steering shaft 11 in the vicinity of the steering handle 12. As shown in FIGS. 4 to 7, the cancel cam 10 includes a cam body 101, a flange portion 102, and three cancel projections 103, which are integrally formed.

  The cam body 101 is formed in a substantially cylindrical shape, and its upper inner diameter D1 is formed to be larger than the lower inner diameter D2.

  The flange portion 102 is formed in a ring shape on the lower outer periphery of the cam body 101.

  The cancel protrusion 103 is provided so as to protrude from the outer peripheral surface of the flange portion 102 at the same angle (120 degrees in the present embodiment) in the radial direction from the axis (center) of the cancel cam 10. The cancellation protrusion 103 is formed such that its tip (outer peripheral side) is curved when viewed from the axial direction.

  Two long holes 104 and 104 are formed in the upper part of the cam body 101 so as to penetrate the diameter direction of the cam body 101. The elongated hole 104 is an opening having the outer peripheral direction of the cam body 101 as a longitudinal direction. Further, an insertion hole 11 a is formed in the steering shaft 11 in a direction perpendicular to the axial direction of the steering shaft 11 so as to correspond to the long holes 104 and 104.

  The transmission shaft 50 is for transmitting the rotational force of the steering shaft 11 to the cancel cam 10. The transmission shaft 50 is configured by a roll pin. The transmission shaft 50 is inserted in a state where the long holes 104 and 104 of the cancel cam 10 and the insertion hole 11a of the steering shaft 11 are substantially matched.

  The diameter of the insertion hole 11a is slightly smaller than the diameter of the transmission shaft 50, and is prevented from coming off by driving the transmission shaft 50 into the insertion hole 11a.

  Hereinafter, the cancel operation by the cancel cam 10 having the above-described configuration will be described.

  In the state of the neutral position N of the operation lever 20 shown in FIG. 4, the inside of the adjustment holding mechanism 30 is as follows.

The moderation members 34 and 34 press-contact the moderation valley portions 31a and 31a at the left and right centers by the urging force of the first urging members 33 and 33 in the arm portions 32f and 32f, respectively.
On the other hand, the pressing portion 42 of the claw member 40 receives the urging force of the second urging member 36 via the movable member 35, and the guide shaft 43 of the claw member 40 receives the urging force of the third urging member 37. . Therefore, when the claw member 40 receives the urging force in the axial direction of the operation lever 20, the guide shaft 43 of the claw member 40 comes into contact with the guide peak portion 32 c of the bracket 32, and the rotation trajectory T of the cancel cam 10. The contact part 41 is located outside. That is, the claw member 40 is in the “free position”.

  When the operation lever 20 is turned forward from the neutral position N about the fulcrum shaft 32a, it is held at the left turn direction indicating position L by the adjustment holding mechanism 30. Further, when the operation lever 20 is rotated backward from the neutral position N about the fulcrum shaft 32a, it is held at the right turn direction indicating position R by the adjustment holding mechanism 30.

  Here, in the cancel structure of the turn signal switch of the present embodiment, the adjustment holding mechanism 30 is configured symmetrically in the front-rear direction when the operation lever 20 is in the neutral position N. Therefore, for the sake of convenience, description of the operation when the operation lever 20 is set to the left turn direction instruction position L is omitted, and description is made only when the operation lever 20 is set to the right turn direction instruction position R.

  The operation lever 20 at the neutral position N shown in FIG. 4 is rotated backward about the fulcrum shaft 32a in order to set the right turn direction indicating position R. At this time, the moderation member 34 engaged with the right and left central moderation valley portions 31a and 31a moves to the adjacent moderation valley portion 31a beyond the adjacent moderation mountain portion 31b in the rotation direction, and the moderation valley portion 31a is moved to the moderation valley portion 31a. While being pressed, it is locked at the position shown in FIG. On the other hand, since the guide peak portion 32c of the bracket 32 is displaced from the axial center of the operation lever 20 at the neutral position N, the guide shaft 43 is moved from the guide peak portion 32c to the guide valley by the biasing force of the third biasing member 37. It slides to the part 32b and is located in the guide valley part 32b. Then, the contact portion 41 of the claw member 40 moves to the inside (on the cancel cam 10 side) of the rotation trajectory T of the cancel cam 10 that rotates together with the steering shaft 11. That is, the claw member 40 moves to the “lock position” shown in FIG. In this state, the pressing portion 42 of the claw member 40 is in pressure contact with one (rear) contact surface 35a of the movable member 35 and the locking projection 35b.

  By operating each member in the adjusting and holding mechanism 30 and the claw member 40, the front guide shaft 43 (the guide shaft 43 on the back side in FIG. 5), which is the operating rod, slides the turn signal switch. "ON", and turn signals 71 and 71 on the right side of the tractor 1 shown in FIG.

  Thereafter, when the operator further rotates the steering handle 12, the steering shaft 11 rotates clockwise, and the tractor 1 turns right. Here, with the clockwise rotation of the steering shaft 11, the cancel cam 10 shown in FIG. 5 rotates in the X direction shown in FIG. Then, the contact portion 41 of the claw member 40 comes into contact with the cancel projection 103 and is driven by the clockwise rotation of the cancel cam 10, so that the claw member 40 rotates counterclockwise (leftward) about the guide shaft 43. . At this time, since there is nothing that regulates the rotation of the pressing portion 42, the contact portion 41 rotates without resisting the rotation of the cancel projection 103. Immediately after the contact between the contact portion 41 and the cancel projection 103 is eliminated, the claw member 40 rotates rightward and again enters the “lock position” state shown in FIG. Therefore, since the claw member 40 does not press any part of the movable member 35, the movable member 35 and the bracket 32 in the adjustment holding mechanism 30 are in the neutral position N while holding the operation lever 20 at the right turn direction indicating position R. There is no return to

  When the right turn of the tractor 1 is completed, the steering shaft 11 rotates in the opposite direction (to return to the original position) in order to go straight. When the cancel cam 10 rotates in the Y direction shown in FIG. 9, that is, the left direction along with this rotation, the contact portion 41 of the claw member 40 comes into contact with the cancel projection 103, and the claw member 40 moves rightward about the guide shaft 43. Rotate. Then, the pressing portion 42 of the claw member 40 presses the contact surface 35 a that is a contact portion with the movable member 35. Accordingly, the movable member 35 uses the other engaging portion 35c and the support portion 32d as fulcrums, and one side of the movable member 35 presses the support portion 32d. The bracket 32 rotates leftward about the fulcrum shaft 32a by pressing the support portion 32d on one side. The guide shaft 43 of the claw member 40 engages with the guide peak portion 32c while sliding on the guide valley portion 32b of the guide hole. Accordingly, the claw member 40 moves to the “free position”. At this time, the moderation member 34 moves against the biasing force of the first biasing member 33 over the moderation peak portion 31b and to the moderation valley portion 31a at the center of the left and right. The moderation member 34 presses the moderation valley portion 31 a by the urging force of the first urging member 33. Then, the operation lever 20 returns to the neutral position N shown in FIG. 5 and turns the turn signal switch “OFF” by the guide shaft 43. Then, the blinking of the right turn signal 71/71 of the tractor 1 ends.

  Next, the operation of the cancel cam structure of the present embodiment when the cancel protrusion 103 of the cancel cam 10 is positioned at the “lock position” of the claw member 40 as shown in FIG. 10 will be described.

  When the operating lever 20 moves from the neutral position N to the right turn direction indicating position R, the claw member 40 moves into the rotation locus T. When the cancel protrusion 103 of the cancel cam 10 is at the “lock position” of the claw member 40, the cancel protrusion 103 hinders the movement of the claw member 40, and the claw member 40 may move to the “lock position”. The control lever 20 returns to the neutral position N.

  However, in the cancel cam of this embodiment, when the claw member 40 moves from the “free position” to the “lock position”, the cancel projection 103 and the contact portion 41 of the claw member 40 come into contact with each other. The claw member 40 presses the cancel projection 103 in the moving direction, but since the one end (tip) of the cancel projection 103 is formed in a curved surface, the cancel is performed so as to avoid this pressing force. The cam 10 rotates.

  At this time, due to a gap (space) formed by the long hole 104 formed in the cam body 101 and the transmission shaft 50, the position of the steering shaft 11 and the transmission shaft 50 remains unchanged, and only the cancel cam 10 can be rotated. It has become. That is, due to the pressing force of the claw member 40, the cancel cam 10 can be rotated until the transmission shaft 50 and the long hole 104 come into contact with each other as shown in FIG. it can. The cancel cam 10 has a lower inner diameter D2 of the cam body 101 larger than the upper inner diameter D1 (see FIG. 7D), so that friction with the steering shaft 11 is reduced. The steering shaft 11 is easy to rotate. Accordingly, even when the canceling protrusion 103 is in the “lock position”, the adjustment holding mechanism 30 is operated by the operation lever 20 without the movement of the claw member 40 to the “locking position” being prevented by the canceling protrusion 103. Can be held at the right turn direction indicating position R.

  In addition, as shown in FIG. 12, in the state where the operation lever 20 is held at the right turn direction instruction position R (or the left turn direction instruction position L), the movements of the claw member 40 and the cancel protrusion 103 may be synchronized with each other. is there. Also in this case, this engagement can be avoided by forming the long hole 104 in the cancel cam 10.

  In a state where the operation lever 20 shown in FIG. 5 is held at the right turn direction indicating position R, the claw member 40 comes into contact with the cancel protrusion 103 when the cancel cam 10 rotates clockwise together with the steering shaft 11 shown in FIG. And the contact release are repeated, and the claw member 40 is in an unstable state in which it swings. At this time, the movement of the cancel projection 103 of the cancel cam 10 and the claw member 40 may be synchronized, and both as shown in FIG. In this case, in the cancel cam structure of the present embodiment, when the claw member 40 and the cancel protrusion 103 are engaged with each other, the cancel cam 10 is attached to the steering shaft 11 by the gap between the long hole 104 and the transmission shaft 50. It rotates to the right (see the positions of the long hole 104 and the transmission shaft 50 in FIG. 11). That is, the force for engaging the claw member 40 and the cancel protrusion 103 can be used as the rotational force of the cancel cam, and the engagement between the claw member 40 and the cancel cam 10 can be avoided.

  If five or more cancel protrusions 103 are provided with respect to the cancel cam 10, the frequency of contact with the claw member 40 increases, and the claw member 40 is likely to swing and become unstable. The timing of returning to the neutral position N is too early, which may make the driver feel uncomfortable. Therefore, as in the present embodiment, it is desirable to provide three cancellation protrusions 103 with respect to the cancellation cam 10 or four at every same angle (90 degrees) in the radial direction from the axis.

  The adjustment holding mechanism 30 is composed of one claw member 40, but is not limited. As shown in FIG. 13, two claw members 140 are arranged on the adjustment holding mechanism 130. It may be configured. However, the “lock position” of the claw member 140 is represented by a two-dot chain line in the drawing, and the “free position” is represented by a solid line. Further, the cancel projection 103 is arranged to be bilaterally symmetrical with the axis of the long hole 104 as the axis of symmetry, but this is not limiting. As shown in FIG. 14, the axis of the long hole 204 is set as the axis of symmetry. The cancel protrusions 203, 203, 203 may be arranged asymmetrically.

As described above, the turn signal operation device of the present embodiment is
A steering shaft 11 to which a steering handle 12 is attached;
A cancel cam 10 that is externally fitted to the steering shaft 11 and has a cancel protrusion 103 (203) that protrudes from the axis of the steering shaft 11 in the outer circumferential direction;
An operation lever 20 for operating the turn signal switch for instructing the traveling direction of the vehicle (tractor 1);
An adjustment holding mechanism 30 (130) attached to the operation lever 20 and holding the operation lever 20 at a neutral position N, a right turn direction indicating position R, or a left turn direction indicating position L;
A claw member 40 (140) which is attached to the adjustment holding mechanism 30 (130) and protrudes so as to come into contact with the cancel projection 103 (203) when being held at the right turn direction indicating position R or the left turn direction indicating position L. A turn signal operating device comprising:
The steering shaft 11 is formed with an insertion hole 11a perpendicular to its axial direction.
The cancel cam 10 (210) is formed with a long hole 104 (204) longer than the diameter of the insertion hole 11a in the outer circumferential direction.
The transmission shaft 50 is inserted into the insertion hole 11a and the long hole 104 (204).

  With this configuration, when the operation lever 20 is operated from the neutral position N to the right turn direction instruction position R or the left turn direction instruction position L, the claw member 40 (140) is placed on the cancel protrusion 103 (203). Even if the contact is made, the cancel cam 10 (210) can be rotated until the transmission shaft 50 and the end of the long hole 104 (204) come into contact with each other, in other words, the transmission shaft 50 in the long hole 104 (204). The claw member 40 (140) and the cancel projection 103 (203) move without being displaced (displaced), and the adjustment holding mechanism 30 (130) turns the operation lever 20 to the right. It can be held at the direction indication position R or the left turn direction indication position L. That is, the adjustment holding mechanism 30 (130) can be prevented from returning to the neutral position N without being held at the right turn direction instruction position R or the left turn direction instruction position L, and the operability of the operation lever 20 is improved. .

  The cancel protrusion 103 (203) of the present embodiment has three locations on the outer periphery of the cancel cam 10 (210) at the same angle (120 degrees or 90 degrees) in the radial direction from the axis of the cancel cam 10 (210). Or four places are formed.

  With this configuration, the contact frequency between the claw member 40 (140) and the cancel projection 103 (203) can be increased during the turning operation, and the operation at the right turn direction indication position R or the left turn direction indication position L. The timing for returning the lever 20 to the neutral position N can be advanced. Therefore, useless turn signals 71 and 71 can be prevented from blinking.

  The cancel protrusion 103 according to the present embodiment has a tip formed in a curved shape.

  With such a configuration, when the claw member 40 (140) comes into contact with the cancel projection 103 (203), the tip of the cancel projection 103 (203) is formed in a curved shape. The force at the time of movement of (140) is released well, the claw member 40 (140) is easily moved, and the operation holding lever 20 is turned to the right turn direction indication position R or the left turn direction indication position L by the adjustment holding mechanism 30 (130). Can be held on. That is, the operation lever 20 can be prevented from returning to the neutral position N without being held at the right turn direction instruction position R or the left turn direction instruction position L, and the operability of the operation lever 20 is improved.

DESCRIPTION OF SYMBOLS 1 Tractor 10 Cancel cam 103 Cancel protrusion 104 Long hole 11 Steering shaft 11a Insert hole 12 Steering handle 20 Operation lever 30 Adjustment holding mechanism 40 Claw member 50 Transmission shaft 71 Turn signal 130 Adjustment holding mechanism 140 Claw member 210 Cancel cam 203 Cancel Projection 204 Long hole N Neutral position L Left turn direction indication position R Right turn direction indication position

Claims (3)

A steering shaft to which a steering handle is attached;
A cancel cam that is externally fitted to the steering shaft and has a cancel protrusion that protrudes in an outer circumferential direction from the axis of the steering shaft;
An operating lever for operating the turn signal switch for instructing the direction of travel of the vehicle;
An adjustment holding mechanism that is attached to the operation lever and holds the operation lever at a neutral position, a right turn direction instruction position, or a left turn direction instruction position;
A turn signal operating device comprising a claw member attached to the adjustment holding mechanism and protruding so as to come into contact with the canceling protrusion when being held at a right turn direction indicating position or a left turn direction indicating position;
The steering shaft is formed with an insertion hole perpendicular to its axial direction,
In the cancel cam, a long hole longer than the diameter of the insertion hole is formed in the outer peripheral direction,
A turn signal operating device, wherein a transmission shaft is inserted into the insertion hole and the elongated hole.   2. The turn signal operation device according to claim 1, wherein the cancel protrusion is formed at three or four positions on an outer periphery of the cancel cam at an equal angle in a radial direction from an axis of the cancel cam. .   The turn signal operation device according to claim 1 or 2, wherein the cancel protrusion has a curved end.

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