JP3514818B2 - Prevention of sudden start of continuously variable speed running vehicle - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a sudden start prevention mechanism in a traveling vehicle such as a tractor or the like that is continuously variable in speed by depressing a pedal. 2. Description of the Related Art Conventionally, a traveling vehicle such as a tractor equipped with a continuously variable transmission such as an HST transmission and having a continuously variable transmission by pedal operation has been known. Also, a configuration is known in which a brake lock lever for fixing the vehicle in a braked state is provided in order to stop the vehicle at the start of work or the like irrespective of engine start or gear shifting operation. However, in the related art, when the brake lock lever is engaged, a shift operation pedal is returned to a neutral position.
With a simple configuration, it has not been fixed quickly and reliably in the neutral position. If the shift operation pedal is not securely fixed to the neutral position when the brake is locked, for example, in the case of an HST transmission, the hydraulic oil moves in the hydraulic circuit of the device. When the brake lock lever is released, the vehicle suddenly starts, which is very dangerous. Therefore, there is a need for a configuration that reliably holds the shift operation pedal at the neutral position when the brake is locked. Ma
Two pedal positions, one for standard height and one for tall people.
Can be changed when the brake is locked in both cases.
Ensure that the speed control pedal is fixed in the neutral position
It is composed. [0004] The problems to be solved by the present invention are as described above. Next, means for solving the problems will be described. A shift operation pedal 1 for continuously variable shifting;
In a traveling vehicle having the brake pedal 2, a brake lock lever 3 is provided to lock the brake pedal 2 at a brake depression position, and by rotating the brake lock lever 3, the brake pedal 2 is in a brake locked state. In the configuration in which the shift operation pedal 1 is fixed to the neutral position, the shift operation pedal 1 is shifted below the rotation axis 1a.
Neutral arm having a link arm 1b for use and a locking pin 1d.
And a return engagement arm 1c protruding therefrom.
Two pivot holes 14a and 1 at which the lower end of the arm 1b is pivotally supported.
4b, and one of the pivot holes 14a is
For standard height setting, the other pivot hole 14b is tall
Is used for setting the height of a long person.
The locking pin when set to the supported standard height
1d engaging portion 3c and tall person pivotally supported in pivot hole 14b
The engaging portion 3 of the locking pin 1d when the height is set.
d . Next, the operation will be described. Since the rotation of the brake pedal is suppressed while the brake is applied using the brake lock lever, and the shift operation pedal can be guided to the neutral position using the engagement portion of the brake lock lever,
Prevents sudden start after brake lock release. Next, an embodiment will be described. FIG. 1 is an overall side view of a lawn tractor T provided with a sudden start prevention mechanism of the present invention, FIG. 2 is a plan view of a main part of a brake lock lever, a brake pedal, and a shift operation pedal, and FIG. FIG. 4 is a side view of the main part when the brake is locked, FIG. 5 is a side view of the main part when the brake is locked for a tall person, and FIG. 7 is a plan view, FIG. 8 is a rear view of the same, FIG. 9 is a side view of a main part of the constant-speed traveling apparatus, FIG. 10 is a rear view of a main part of the same, and FIG. 5A is a front view showing the shape of a detent hole of the rotating cam 32 in the constant-speed traveling device, FIG. 5A is a diagram illustrating a round hole, and FIG. FIG. 1 shows a lawn mower tractor T equipped with the sudden start prevention mechanism of the present invention. At the upper part of the frame F, a bonnet 4 for covering the engine is mounted on the front, and a dashboard 5 is erected at its rear end to protrude a steering wheel 6. The part 7 is formed using the upper surface of the frame F, and the right front end thereof has
As shown in FIGS. 2 to 7, the shift operation pedal 1 and the brake pedal 2 are protruded upward from below the frame F, and the brake lock lever 3 protrudes from near the center of the lower end of the dashboard 5. Is established. A seat 8 is provided behind the step portion 7, and a constant speed lever 9 is provided on a side of the seat 8. Further, a front wheel FW is disposed at a front portion of the frame F, and a transmission case M is disposed at a rear portion, and a rear wheel RW is suspended from the transmission case M. A lawn mower 10 having a lawn mowing blade is hung from the abdomen of the lawn mower tractor T. The cut grass is thrown into the catch box 13 mounted on the rear of the lone mower tractor T. Next, the arrangement of the shift operation pedal 1 and the brake pedal 2 and the coupling mechanism between the brake pedal 1 and the shift operation pedal 2 below the frame F will be described with reference to FIGS. First, the L-shaped speed change operation pedal 1 is rotatable back and forth about a rotation shaft 1a as a rotation fulcrum, and as shown in FIGS. Link arm 1b and a neutral return engagement arm 1c protrude, and the lower end of the speed change link arm 1b is at the front end of a speed change rod 14 disposed in the front-rear direction below the frame F. It is pivotally supported by the pivot hole 14a or 14b. As shown in FIGS. 3 and 4, when the gearshift operation pedal 1 is pivotally supported by the pivot hole 14a, the height of the speed change operation pedal 1 is set to a standard height, and as shown in FIG. At times, the height of the speed change operation pedal 1 is reduced, so that a tall person and a person with long legs can easily operate it. The rear end of the transmission rod 14 is connected to a rotating shaft 15a.
Is pivotally connected to the lower end of a shift cam plate 15 that is rotatable around a fulcrum. Of the transmission arm 16 is urged by a spring to return to a neutral state. When the front end of the shift operation pedal 1 is depressed, the shift rod 16 slides rearward, and the shift cam plate 1
5 rotates forward, and the forward speed is determined by the amount of rotation. On the other hand, when the rear end of the shift operation pedal 1 is depressed, the shift rod 14 slides forward, and the shift cam plate 15 Rotates backward, and the reverse speed is determined by the amount of rotation. When the speed control pedal 1 is released, when the constant speed lever 9 is at the neutral position N1, the speed change arm 16 returns to the neutral position, and the speed change cam plate 15 also moves slightly forward of the constant speed lever 9 when the speed change arm 16 returns to the neutral position. To the neutral position N2 at
The speed change operation pedal 1 is also returned to the initial position via 4. The neutral position N1 of the constant speed lever 9 corresponds to a position after the maximum rotation position rearward from the neutral position N2 of the speed change cam plate 15, and therefore does not interfere with the rearward rotation of the speed change cam plate 15. . Next, in the brake pedal 2, a base rotation shaft 2a is rotatably supported by the frame F in the left and right directions, and is provided via a link arm 2b protruding from the base rotation shaft 2a. 8, the front end of the brake rod 18 is pivotally connected, and the rear end of the brake rod 18 is connected via a link mechanism 19 to a brake arm 20 shown in FIG. When the brake pedal 2 is depressed, the brake rod 18 is slid forward and the transmission case M
The brake is applied inside. Further, a base rotation shaft 2 of the brake pedal 2 is provided.
a, a connecting plate 21 which is connected to a part of the frame F and is urged forward by connecting a spring 22 is fixedly provided. The front end of the constant-speed release rod 23 is attached to the rear end of the connecting plate 21. The rear end of the constant speed releasing rod 23 is connected to a rotating cam 32 in a constant speed traveling device described later. When the foot on which the brake pedal 2 is depressed is released, the brake pedal 2 returns to the initial position by the forward bias of the connecting plate 21,
As a result, the brake rod 18 and the constant speed release rod 23 return to the initial position, and the brake is released in the transmission case M. Further, the base rotating shaft 2
a, the brake lock engagement arm 2c is positioned forward and upward on the same plane as the neutral return engagement arm 1c protruding from the inner end of the base rotation shaft 1a of the shift operation pedal 1. It is protruding. Next, the structure of the brake lock lever 3 will be described with reference to FIGS. The brake lock lever 3 is pivotally supported by a lever rotation shaft 3a and is vertically rotatable. A return spring 24 is connected to a part of the frame F in front of its lower end, as shown in FIG. The lever portion is urged to be horizontal. The lever rotation shaft 3a
The front is flat, and the speed change operation pedal 1
Locking pin rotation hole 3 so that a locking pin 1d projecting from the tip of the neutral return engagement arm 1c is inserted and slid.
b is drilled, and the locking pin 1
The engaging portions 3c and 3d are cut out so that d engages. On the other hand, at the lower rear end of the brake lock lever 3,
As described above, a locking pin 2d projecting from the tip of the brake locking engagement arm 2c of the brake pedal 2 is engaged.
The engaging portion 3e is cut out. The brake lock lever 3 having such a configuration
At the time of releasing the brake lock with the lever in the horizontal position, as shown in FIG.
In the state of being inserted into the locking pin rotation hole 3b, the rotation of the locking pin 1d in the locking pin rotation hole 3b when the speed change operation pedal 1 is depressed is free. The gear shift operation is ready. On the other hand, the locking pin 2d of the brake pedal 2 is also disengaged from the engaging portion 3e, and the rotation of the brake pedal 2 is free, and the brake can be applied by freely depressing the pedal. When the foot is released from the brake pedal 2, the brake pedal 2 returns to the initial position. When the lever portion is lifted and the rear end of the brake lock lever 3 is turned upward, the locking pin 2d is fitted into the engaging portion 3e, and further the locking pin 2d
, The brake lock engagement arm 2c is lifted, and thus the brake pedal 2 is rotated downward via the base rotation shaft 2a, and is fixed in a state where the brake is applied. On the other hand, in the speed change operation pedal 1, even if the locking pin 1 d is inserted into the locking pin rotation hole 3 b with the pedal depressed, the rotation of the brake lock lever 3 is accompanied. As a result, the locking pin 1d is guided and fitted into the engaging portion 3c or 3d. FIG.
As shown in FIG.
In this case, the locking pin 1d is fitted into the engaging portion 3c, and the lower end of the speed-change link arm 1b is pivoted as shown in FIG. When the height is set at the height for a tall person pivotally supported by the support hole 14b, the locking pin 1d is fitted to the engaging portion 3d. Thus, the locking pin 1
When d is fitted to the fitting portion 3c or 3d, the speed change operation pedal 1 is fixed to the initial position, that is, the neutral position. When the brake pedal 2 is depressed to release the brake lock lever 3, the locking pin 2d
Pushes down the engaging portion 3e to rotate the rear end of the brake lock lever 3 downward, and the locking pin 2d is disengaged from the engaging portion 3e soon, and the brake lock lever 3 returns the return spring 24. With the force, the lever returns to the initial position where the lever is horizontal, and the locking pin 1d is also disengaged from the engaging portion 3c or 3d, and the speed change operation pedal 1 can be freely operated. Since the shift operation lever 1 is held at the neutral position, the vehicle does not suddenly start with the release of the brake lock. Next, FIG. 9 to FIG.
A description will be given from 1st. The constant speed lever 9 is connected to the seat 8 as described above.
, But does not protrude above the upper surface of the seat 8 of the seat 8 as shown in FIG.
Since the center of gravity is located at the rear without any obstacle to getting on and off, when the constant speed lever 9 is rotatable, it naturally returns to the neutral position N1 at the rear. . Then, the shift cam plate 15 which is rotated forward to be displaced when the shift operation pedal 1 is depressed.
Is fixed at the displaced position and the vehicle is driven at a constant speed. As shown in FIG. 6 or FIG. 9, the upper end of the speed change cam plate 15 is located forward of the base of the constant speed lever 9, and when the constant speed lever 9 is rotated forward. , The base end 9b of which abuts. And FIG.
As shown at 0, a turning plate 9a extends downward from a base end 9b of the constant speed lever 9, and the turning plate 9a projects from a fixed plate 25 projecting from the frame F. A pressing plate 28 is externally fitted on the moving shaft 26, and a pressing cam 28 is externally fitted on the rotating shaft 26, and a fixed cam 29 is fitted around the rotating shaft 26 in a holding portion 28 a of the pressing plate 28. The fixed cam 29 and the holding portion 28a of the pressing plate 28 are integrally fixed to the rotating shaft 26 by a fixing pin 30, and the rotating plate at the base end of the constant speed lever 9 is provided. Rotation suppressing member A contacting 9a
Is formed. Then, the fixed plate 25 and the rotating plate 9a
Friction plates 27 are interposed in the gap between the pressing plate 28 and the rotating plate 9a. On the outer surface of the fixed cam 29, steel balls 31 constituting a detent are fitted, and a rotating cam 32 connected to the constant speed releasing rod 23 via a pin 34 is provided. , And is externally fitted to the rotary shaft 26 so as to be able to contact the fitting surface of the fixed cam 29 with the steel balls 31. The rotating cam 32 is provided with detent holes 32a so that the steel balls 31 of the fixed cam 29 can be fitted therein, and a nut 26a is screwed into an end of the rotating shaft 26. And the nut 26
a on the rotation shaft 26 between the rotation cam 32 and the rotation cam 32.
The rotating cam 32 is pressed against the fixed cam 29 by the spring 33, and the pressing force causes the steel balls 31 of the fixed cam 29 to be constantly rotated by the rotating cam 32. The fixed cam 29 and the rotating cam 32 are pressed against each other, and the urging force of the spring 33 is applied to the fixed cam 29, the pressing plate 28, Transmitted to the friction plate 27, presses and fixes the rotating plate 9a,
The constant speed lever 9 is pressed and fixed. When the constant speed release rod 23 is slid backward by depressing the brake pedal 2 to rotate the rotary cam 32, the detent holes 32a
The steel balls 31 are disengaged from the rotating cam 32.
Rides on the steel balls 31, contracts the spring 33,
Accordingly, the pressing force between the rotating plate 9a and the pressing plate 28 via the friction plate 27 is loosened, and the constant speed lever 9 becomes rotatable. In this state, as described above, the constant speed lever 9 naturally rotates rearward because of the center of gravity behind, and does not interfere with the neutral position N1, that is, the rotation of the upper end portion of the speed change cam plate 15. When the foot is released from the brake pedal 2, the constant speed releasing rod 23 slides forward, and the rotating cam 32 returns to the original position, and the detent holes 32a and 32
The steel balls 31 are fitted in a, and the constant speed lever 9
It is fixed at the neutral position N1. On the other hand, in the brake pedal 2, the rotating cam 32 is rotated by the pressing force of the spring 33 in addition to the spring 22, and the steel balls 3 are inserted into the detent holes 32a.
In order for the rotating cam 32 to return to the initial state, the constant speed release rod 23 is returned to the initial state, so that the brake pedal 2 immediately returns to the initial position. The detent hole 3 in the rotary cam 32
The 2a and 32a can be formed in a round hole shape as shown in FIG. 11 (a) to simplify the configuration. In addition, in order to reduce the operation force at the start of rotation, the rotation direction is taken into consideration. As shown in FIG. 11B, a long hole-shaped detent hole 32a 'is formed.
32a 'is also conceivable. A constant-speed traveling operation based on the constant-speed traveling device having such a configuration will be described. First, when the constant speed lever 9 is in the neutral position N1 and the vehicle travels forward, the speed is changed in proportion to the amount of depression of the shift operation pedal 1, and if the stepping force is reduced, the speed is changed as described above. Due to the restoring force of the arm 16 and the speed change cam plate 15 to the neutral state, it is possible to reduce the speed by the loosened amount. When the foot is released, the vehicle completely returns to the neutral state and can stop running, and the shift operation pedal 1 is also returned to the initial position. In forward running, when the speed change operation pedal 1 is fixed at the position where the speed change operation pedal 1 is depressed and constant speed running is performed, the constant speed lever 9 is moved to the friction plates 27. When the speed change operation pedal 1 is depressed, the base end 9b of the constant speed lever 9 is pressed against the upper end of the speed change cam plate 15 which is turned forward. Even when the hand is released from the constant-speed lever 9, the constant-speed lever 9 cannot rotate due to the urging force of the spring 33 and the frictional force of the friction plates 27. Is fixed at a position pressed against the member to return to the neutral position N2, and the speed change arm 16 is fixed at that position, and a constant speed running state is established. If the constant-speed lever 9 is turned backward against the frictional force of the friction plates 27, 27, if the shift operation pedal 1 is not depressed,
The speed can be reduced by the amount of rotation, and the traveling cam plate 15 can be further stopped by rotating the upper end of the transmission cam plate 15 backward to the neutral position N2 to stop the traveling, and the constant speed release state can be established. Next, when the brake pedal 2 is depressed, the brake is applied, while the constant speed releasing rod 22 slides rearward, and the rotating cam 32 of the constant speed lever mechanism as described above.
Is rotated, and the constant speed lever 9 is turned freely.
If the driver immediately returns to the neutral position N1 under his own weight and releases his foot from the brake pedal 2, the constant speed lever 9 is fixed at the neutral position N1 and even if the speed change operation pedal 1 is depressed, The rotation of the plate 15 is a constant speed lever 9
Because it is not disturbed by the, it returns to the initial state immediately after releasing the foot. During reverse travel, the speed change cam plate 15 is located behind the neutral position N2,
Is further rearward than the speed change cam plate 15 and does not interfere with the return of the speed change cam plate 15 to the front neutral position N2. Therefore, during reverse traveling, if the stepping force on the speed change operation pedal 1 is reduced, the speed change cam plate 15 is rotated toward the neutral position N2 and deceleration is possible. Since it is rare to maintain reverse running for a long time, constant speed operation is almost unnecessary, and there is no problem with this. If the constant speed lever 9 is slightly rotated forward, the amount of backward rotation of the speed change cam plate 15 is limited, and therefore, the maximum reverse speed can be limited. As described above, since the detent is interposed between the rotation suppressing member A and the rotation cam 32 in the constant-speed traveling device, the detent comes off when the brake pedal is depressed. Since the pressure contact between the suppressing member A and the rotating cam 32 is immediately released, the constant speed lever 9 can be freely rotated immediately, and immediately returns to the initial position by its own weight. When the foot is released from the brake pedal 2, the detent is immediately engaged by the spring pressing force, and the rotation of the constant speed lever 9 is suppressed, while the brake pedal 2 is reliably returned to the initial position. As described above, the present invention has the following advantages. That is, by operating the brake lock lever, the brake can be fixed in a state where the brake is applied, and at the same time, the speed change operation pedal is quickly and reliably guided and fixed to the neutral position, and the brake lock lever is unlocked and the brake is released. At the moment when the gear is released, the gearshift operation pedal is in the neutral position, so that the vehicle does not suddenly start, greatly improving the safety of the continuously variable speed traveling vehicle. Further, the configuration is simple, the number of parts is small, and the cost is reduced. Also, when pivoted to the pivot hole 14a,
The height of the shift operation pedal 1 is set to a standard height,
When pivotally supported by the support hole 14b, the height of the speed change operation pedal 1 is increased.
Low, making it easy to operate even for tall and long legs
You.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall side view of a lawn tractor T provided with a sudden start prevention mechanism of the present invention. FIG. 2 is a main part plan view of a brake lock lever, a brake pedal, and a shift operation pedal. FIG. 3 is a side view of the main part when the brake lock is released. FIG. 4 is a side view of the main part when the brake is locked. FIG. 5 is a side view of the main part when the brake is locked when the same is set for a tall person. FIG. 6 is a side view showing a coupling mechanism between the speed change operation pedal and the brake pedal and the constant-speed traveling device. FIG. 7 is a plan view of the same. FIG. 8 is a rear view of the same. FIG. 9 is a side view of a main part of the constant-speed traveling device. FIG. 10 is a rear view of the main part. 11 is a front view showing a shape of a detent hole of the rotating cam 32 in the constant-speed traveling device, wherein FIG.
(B) is a diagram of a long hole. [Description of Signs] F Frame 1 Transmission operation pedal 1a Rotating shaft 1b Transmission link arm 1c Neutral return engagement arm 1d Locking pin 2 Brake pedal 2a Base rotation shaft 2b Link arm 2c Brake lock engagement arm 2d Locking pin 3 Brake lock lever 3a Lever rotating shaft 3b Locking pin rotating hole 3c Engaging part 3d Engaging part 3e Engaging part 24 Return spring

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Koji Suematsu 428 Enami, Okayama City Inside of Seirai Industry Co., Ltd. (56) References JP-A-4-364656 (JP, A) JP-A-4-197835 (JP, A) JP-A-3-255264 (JP, A) JP-A-7-271464 (JP, A) JP-A-63-189930 (JP, U) JP-A-3-43035 (JP, U) JP-A-60 164 230 (JP, U) Fully open 48-53730 (JP, U) Fully open 62-191537 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B60K 20/00- 20/08 F16H 59/00-61/12 F16H 61/16-61/36 F16H 63/00-63/48 G05G 1/00-25/04

Claims (1)

(57) [Claim 1] In a traveling vehicle having a shift operation pedal 1 for continuously variable transmission and a brake pedal 2, a brake lock lever is provided to lock the brake pedal 2 at a brake depression position. 3 is provided, and the brake pedal 2 is in a brake locked state by a rotation operation of the brake lock lever 3,
In a configuration in which the speed change operation pedal 1 is fixed at the neutral position, the speed change link is provided below the rotation shaft 1a of the speed change operation pedal 1.
Neutral return engagement with arm 1b and locking pin 1d
And the transmission link arm 1
b, two pivotal support holes 14a and 14b are provided.
The gear shift operation pedal 1 has a standard height.
For setting, the other pivot hole 14b is for tall and long legs
Height, and set to a standard height pivotally supported by one of the pivot holes 14a.
The engaging portion 3c of the locking pin 1d and the pivot hole
If the height is set for tall people pivoted to 14b,
A sudden start prevention mechanism for a continuously variable speed traveling vehicle, comprising an engaging portion 3d of the locking pin 1d .