JP2000071800A - Power vehicle gear box - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conduct gear changing for a vehicle safely and surely, even on a slope or the like where gear changing is dangerous while the operator is riding thereon, by providing a gear changing operation part near the driver's seat for operating the gear box mounted on the vehicle, and providing another gear changing operation part for operating the gear box at the front of the vehicle as well. SOLUTION: An operation lever 7 for primary gear changing is added, and a bracket 92 attached to the front of the vehicle is pivotally attached to an advancing/retracting lever 96 for supplement, which is then connected to the side of an operation lever 7 for primary shifting via a push-pull wire 98. In this construction, if the operator goes around the vehicle to the front thereof and moves the advancing/retracting lever 96 in the longitudinal direction, gear changing in the primary gear changing portion via the push-pull wire 98 is made possible. Accordingly, vehicle gear changing is enabled to be conducted safely and surely even when the vehicle is on the slope or entering or exiting the rice fields where gear changing is dangerous while the operator is riding thereon.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission for a small power vehicle such as a riding cultivator, for example, and relates to a place where it is difficult for an operator to operate the body while riding on the vehicle, for example, a ridge or a slope. Thus, the speed change operation can be performed easily and safely.

[0002]

2. Description of the Related Art Conventionally, in a power vehicle such as a tractor, a shift operation is performed by pushing and pulling a shift operation lever provided on a side portion of a cockpit, or by pressing a shift button to switch a hydraulic transmission. Like that.

[0003]

In such a conventional tractor, the operator cannot get down from the airframe even in an unstable place where the airplane tilts forward or horizontally. However, even if it is somewhat dangerous, the operator has to perform the shifting operation while riding on the tractor.

[0004]

The present invention has been made in view of the above-mentioned problems, and has taken the following technical measures. That is, a power shift vehicle provided with a shift operation section for operating a transmission mounted on the body near the cockpit, and further provided with another shift operation section for operating the transmission on the front of the body. Of the transmission.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. First, a description will be given of the configuration. Reference numeral 1 denotes a tractor as a small power vehicle having a small-diameter front wheel 2 and a large-diameter rear wheel 3 and having the front wheel 2 as a steering wheel. An engine 5 is provided at the front of the body of the tractor 1, and the rotational power of the engine 5 is transmitted to a transmission (FIG. 9) in a transmission case 6 to reduce the speed appropriately, and the power is supplied to the rear wheel 3 and the front wheel 2. Is configured to be transmitted. Here, the transmission in the transmission case 6 will be described with reference to FIG. Reference numeral 14 denotes an input shaft protruding from the front of the mission case 6 and an engine 5.
It is driven by obtaining rotational power from. A gear 16 is fixed to the rear end of the input shaft 14, and a gear 17 on the clutch side always meshes with the gear 16. Gear 17 has clutch 1
8 clutch drums 18a are integrally fixed,
A number of friction plates 22 are interposed between the clutch drum 18a and the boss 20 which rotates integrally with the clutch support shaft 19. A ring body 24 is provided on the clutch support shaft 19 in a non-rotatable state. When the ring body 24 is moved forward by depressing the clutch pedal 9, the interval between the friction plates 22 is widened and the clutch 18 is disengaged. When the clutch pedal 9 is further depressed, the ring 24
The lining 25 fixed to the front of the boss 20 is pressed against the end face of the boss portion 20 to apply a brake to the boss portion 20 to stop the rotation of the clutch support shaft 19. In the figure, reference numeral 26 denotes a spring member.

A small-diameter gear 27 is fixed to the rear end of the clutch shaft 19, and the large-diameter gear 3
0a is always engaged. The two-stage gear 30 is freely rotatably fitted on a transmission shaft 32 described later. Four gears 34, 35, 3 are provided on a shift countershaft 33 provided behind the clutch support shaft 19 and provided coaxially therewith.
6, 37 are integrally fixed by spline fitting. The gear 34 always meshes with the small-diameter gear 30b of the two-stage gear 30, and transmits the rotational power of the clutch support shaft 19 to the counter shaft 33.

The gear 35 is a first gear 3 on the transmission shaft 32.
The gear 36 meshes with the gear 40 for the second speed, and the gear 37 meshes with the gear 41 for the third speed on the transmission shaft 32 at all times. Note that these gears 3
A plurality of locking grooves 44 are provided on the inner peripheral surface of the gears 9, 40, 41, and are depressed in the radial direction. And the speed change shaft 32 are integrally rotated.

The keys 47, 47 are attached to a single shifter shaft 48 made of a solid rod. Specifically, the rear end (right side) of the shifter shaft 48 is cut out in a slit shape to form a slit. Two keys 47, 47 are pivotally mounted on the part.
One spring 4 is provided between the pair of keys 47 and 47.
9 are interposed, and the claws 47a of the keys 47 and 47 are provided.
The projection 47a extends outward so that the projections of the claws 47a and 47a enter the locking groove 44.

A neutral collar 50 is provided immediately before the first speed gear 39, and a reverse gear 51 is loosely fitted on the speed change shaft 32 in front of the neutral collar 50. Reference numeral 52 denotes a back counter gear attached to the reverse counter shaft 46, which always meshes with the gear 35, and keys 47, 47.
When the gear enters the groove 44 of the reverse gear 51, the transmission shaft 32 rotates in the reverse direction. Reference numeral 53 denotes a circumferential locking groove provided at the front end of the shifter shaft 48. A shifter (not shown) is fitted into this groove 53, and the operation lever 7 for main transmission is reciprocated in the front-rear direction. The shaft 48 moves in the front-rear direction, and one of reverse, first forward speed, second forward speed, and third forward speed is selected.

Further, two sets of two-stage gears 54 and 55 cannot be moved back and forth on the axis of the shift counter shaft 33,
The large-diameter gear 54 a on the front side is always meshed with the gear 57 at the rear end of the speed change shaft 32. The small-diameter gear 54b of the two-stage gear 54 meshes with the large-diameter gear portion 59a of the sub-transmission gear 59 that is spline-fitted on the drive pinion 58 so as to be movable back and forth. An internal gear 59b is provided on the front inner peripheral portion of the sub-transmission gear 59, and moves the sub-transmission gear 59 to the front side so that the internal gear 5
9b is engaged with the gear 57 at the rear end of the speed change shaft 32, so that the "high speed" of the sub speed change is obtained.
When "a" is meshed with the small-diameter gear 54b of the two-stage gear 54, "low speed" of the subtransmission is obtained. A gear 60 that rotates integrally with the drive pinion 58 is provided behind the auxiliary transmission gear 59. The gear 60 and a small-diameter gear 55 a of the second-stage gear 55 and a large-diameter gear 55 of the second-stage gear 55 are provided.
b, the power is transmitted to the front wheels 2 via the gears 62 on the front wheel drive shaft 61 sequentially. In this embodiment, no clutch operation is required when operating a key shift type main transmission comprising first reverse speed, first forward speed, second forward speed, and third forward speed, and the operation lever 7 is simply operated. The gear can be shifted simply by moving it forward and backward. However, when the on-off operation of the high-low two-stage auxiliary transmission is required, the operation of the clutch 18 is necessary.

Next, the steering mechanism of the tractor 1 will be described. 1 to 3, reference numeral 70 denotes a steering handle, 71 denotes a steering gear box, 72 denotes a pitman arm, 73 and 73 denote tie rods, 74 and 7.
4 is a knuckle arm. Steering handle 70
When the is turned, the pitman arm 72 is rotated about the vertical axis, and the knuckle arm is
The direction of the front wheels 2, 2 is changed by rotating the wheels 74, 74 in the left-right direction. More specifically, the outer ends of tie rods 73 are fixed to the rear end of a front wheel final case 75 which supports the front wheels 2 and 2 and is rotatable around the axis of a kingpin (not shown). When the handle 70 is rotated, the front wheel final cases 75, 75 are rotated.

A stay 80 is provided on the upper part of the front case 75 on one side so as to stand upward integrally with the knuckle arm 74. The stay 80 has a fan-shaped upper end. A large-diameter gear portion 81 is provided. On the other hand, a shaft 85 is fixed on an extension of the axis of the king pin above the fixed-side front wheel final case 84. The shaft 85 is provided with a small-diameter gear portion 86 which always meshes with the large-diameter gear portion 81. . A universal joint shaft 90 is detachably attached to the upper end of the shaft 85, and the upper end of the universal joint shaft 90 projects forward.

Reference numeral 92 denotes a bracket attached to the front part of the fuselage, which rotatably supports the universal joint shaft 90 via a ball joint 93. Reference numeral 95 denotes a lever attached to the end of the universal joint shaft 90. The lever 95 is vertically rotated within a range of 180 degrees as shown in FIG. 85, a small-diameter gear portion 86, and a large-diameter gear portion 81 in that order.
The gear 75 is rotated. In this embodiment, when the lever 95 is lowered, the front wheel 2 rotates to the left, and when the lever 95 is raised, the front wheel 2 rotates to the right. Reference numeral 96 denotes an auxiliary forward / reverse lever pivotally attached to the bracket 92, and is connected to the main transmission operation lever 7 via a push-pull wire 98.

Therefore, when the operator goes around the front of the body and moves the forward / reverse lever 96 in the forward / backward direction, the main transmission can be shifted through the push-pull wire 98. The range in which the gear can be shifted is configured so that the gear can be shifted in the range of the first forward speed and the first reverse speed in consideration of safety. That is, the bolt 97 is provided inside the bracket 92 to regulate the first speed position of the lever 96.

The specific structure of the shift operation section will be described with reference to FIG.
The cylindrical boss 100 of the forward-reverse lever 96 is removably fitted to the support shaft 99 from the lateral outside. A plate 102 bent in an L-shape as viewed from the front is fixed to the lower surface of the cylindrical boss 100, and the tip of a round bar 105 urged upward by a spring 103 enters a countersunk fir hole 107 of the support shaft 99. The forward / reverse lever 96 and the support shaft 99 are configured to be integrated. When the round bar 105 is pulled down and its tip is pulled out from the countersink hole 107 and the end of the locking piece 108 is hooked on the upper end of the long hole 108 of the plate 102, the forward / reverse lever 96 becomes free and swings freely in the forward / backward direction. I can do it. Therefore, in this state, the forward / reverse lever 96
Cannot be used to switch the main transmission section.
In the above embodiment, reference numeral 101 denotes a throttle lever, 104 denotes a hydraulic lever, 136 denotes a lining, 137.
Is a collar, 138 is a disc spring, and 139 is a tightening nut.

Next, FIGS. 5 and 6 will be described. In this embodiment, when the sub-transmission lever is operated, the main transmission is operated when the sub-transmission lever is switched to the high-speed side, and the main transmission operation is not performed only when the sub-transmission lever is switched to the low-speed side. This is made possible with a clutch. Reference numeral 111 denotes a clutch pedal, and 112 denotes a traction arm having a saw-toothed locking portion on the upper surface. The restraining arm 112 rotates about a fulcrum 113, the clutch pedal 111 rotates about a fulcrum 115, and the clutch pedal 111 and the restraining arm 112 are connected by a rod 116. In this embodiment, the main transmission lever and the sub transmission lever are constituted by the same lever 110, and when this lever 110 is swung in the right and left directions, the sub transmission is switched between high and low and the front and rear directions are changed. To 1st reverse, 1st forward to 4th forward
Switch to fast. More specifically, the boss 117 of the lever 110 swings around the axis 118, and when the lever 110 is tilted to the right (in a dotted line) as shown in FIG. It is configured to switch to the low speed side when tilted to. The description of the linkage switching mechanism between the lever 110 and the subtransmission is omitted.

Further, the lever 110 can be swung in the front-rear direction about the shaft 120. By moving the lever 110 back and forth, the above-described main transmission is performed via a mechanical linking mechanism such as a rod 121 and a plate 122. The device can be switched. In the figure, reference numeral 124 denotes a spring, 1
25 is a check plate. The check plate 125 is fixed to the boss 117 and moves integrally with the lever 110.

In this embodiment, when the lever 110 is switched to the low speed side, the main transmission can be switched without depressing the clutch pedal 111.
When the lever 110 is switched to the high speed side, the lever 110 cannot be moved in the front-rear direction because the traction plate 125 is in contact with the locking teeth of the traction arm 112. In order to switch the main transmission, the clutch pedal 111 must be depressed to release the traction arm 112 from the traction plate 125.

As described above, when the sub-transmission is switched to the low speed side, the main transmission can be switched by the no clutch operation, but when the sub-transmission is switched to the high speed side, the clutch pedal 111 is operated. Normal clutch operation of depressing and disengaging the clutch is required. Therefore, the operational safety at the time of high-speed running is increased by the amount accompanying the clutch operation.

Finally, the configuration shown in FIGS. 7 and 8 will be described. In the tractor 1 described in this embodiment, the connecting plates 129 of the brake pedals 127 and 127 rotate in conjunction with the sub-shift operation in order to prevent one-sided operation of the brakes when traveling on the road, and the left and right brake pedals 127 are rotated. , 1
27 are automatically connected. More specifically, a locking hook 130 is fixed to an intermediate portion of the left brake pedal 127, and the right brake pedal 12
7, a connecting plate 129 is rotatably mounted around a fulcrum pin 132. At the end of the right brake pedal 127, a normal connecting plate 133 is provided separately from the connecting plate 129.

When the operating lever 110 of the auxiliary transmission is switched to the high speed side, the inner wire 135 is pulled (to the left in FIG. 8), and the connecting plate 129 is rotated clockwise about the fulcrum pin 132. Then, the distal end of the connection plate 129 enters the locking hook 130, and the left and right brake pedals 127, 127 are integrally connected. Conversely, when the lever 110 is moved to the low speed side, the connection plate 129 rotates counterclockwise to release the connection of the brake pedals 127, 127.

[0022]

As described above, according to the present invention, the shift operation section for operating the transmission mounted on the body is provided near the cockpit,
Further, since another shift operation section for operating the transmission is provided also at the front of the body, if the shift operation is performed while riding the vehicle, the shift of the vehicle can be performed safely and reliably even on dangerous slopes or when entering or exiting a field. Operation can be performed, and safety is greatly increased.

[Brief description of the drawings]

FIG. 1 is a side view of a tractor.

FIG. 2 is a front view of the tractor.

FIG. 3 is a plan view of a main part of the tractor.

FIG. 4 is a perspective view of a main part.

FIG. 5 is a side view of a transmission unit.

FIG. 6 is a rear view of a main part.

FIG. 7 is a perspective view of a brake device.

FIG. 8 is a side view of a main part.

FIG. 9 is a cross-sectional view showing a transmission mechanism in a transmission case.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Powered vehicle 2 Front wheel 3 Rear wheel 5 Engine 6 Transmission case 92 Bracket 96 Forward / reverse lever

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3D040 AA01 AA12 AB04 AC07 AD01 3J052 AA07 DB10 GA01 LA07 3J067 AA02 AB06 AC07 AC51 BA32 DA63 FB90 GA14

Claims (1)

[Claims] A shift operation section for operating a transmission mounted on an airframe is provided near a cockpit, and another shift operation section for operating the transmission is also provided at a front portion of the airframe. Transmission for a powered vehicle.