JP2583905Y2 - Traveling gear for work vehicles - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a traveling transmission for a working vehicle such as a combine, rice transplanter, or tractor having a hydraulic continuously variable transmission (HST) as a main transmission and a gear transmission as an auxiliary transmission. Related to the device.

[0002]

2. Description of the Related Art In recent years, there has been known a work vehicle in which a hydraulic continuously variable transmission (HST) is mounted as a traveling transmission and a forward traveling, a reverse traveling, a traveling stop, and an acceleration / deceleration are performed by a single traveling transmission lever. ing. Further, a gear type transmission is arranged at the subsequent stage of the hydraulic type continuously variable transmission to enable a subtransmission and to allow a wide selection of traveling speed.
- is known from 183436 JP like. In addition to the traveling speed change lever for shifting the hydraulic continuously variable transmission, a clutch pedal is provided in the control unit, and in the event of an emergency, depressing the clutch pedal cuts off power transmission and stops traveling. - is known from 147526 JP.

[0003]

Among the above-mentioned traveling transmissions, the former one, in particular, has a gear type auxiliary transmission, so that the traveling speed can be set widely.
Since no emergency power shut-off device is provided, the combine cannot be stopped immediately in response to an unexpected situation. In addition, when the speed of the gear-type auxiliary transmission is changed in accordance with traveling on the road or work, if the motor of the hydraulic continuously variable transmission rotates at a high speed, gear noise is generated at the time of gear shifting, and the gears are rotated. There is a risk that the aircraft will suddenly start with the engagement. In order to prevent this, the traveling speed change lever is operated, the hydraulic continuously variable transmission is returned to the neutral position, and the vehicle is stopped to perform the gear shifting operation. The rotation of the transmission gears on the transmission shaft is locked to each other by the braking action and the load of the traveling axle on the lower side. When the peaks of the transmission gears are meshed, the gears do not mesh and are forcedly meshed. However, there is a problem that the gears are half-meshed and the shift is lost.

Further, in the case of the latter, when the clutch pedal is depressed in an emergency, the power transmission can be cut off and the traveling stopped, but the clutch that cuts off the power transmission is connected to the output shaft of the engine and the hydraulic stepless transmission. Since it is interposed between the devices, even if a gear type auxiliary transmission is provided on the lower side of the transmission of the hydraulic continuously variable transmission to enable the auxiliary transmission, the rotation of the hydraulic continuously variable transmission is There is a problem that the braking operation is performed with the stop and the gear shifting becomes difficult similarly to the former.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and the technical means of the present invention is to provide a hydraulic continuously variable transmission and a gear type transmission that use the power of an engine. In a working vehicle transmitted to a traveling axle via a motor, a gear-type transmission is provided on a motor of a hydraulic continuously variable transmission and a transmission case by connecting an output shaft of an engine and a pump of a hydraulic continuously variable transmission. And via a dog clutch, and by operating the traveling speed change lever,
Move the hydraulic continuously variable transmission to a forward acceleration / deceleration position, a neutral position,
And the traveling speed change lever and the clutch pedal provided on the control unit are moved together.
Linked via the neutral return member pair, said when depresses the clutch pedal both neutral return member is operated in the opposite direction, traveling shift lever of the shifting state is configured to engage the return to the neutral or low speed position On the other hand, the neutral return member
When the clutch pedal is not operated, the clutch pedal
Irrespective of the travel shift lever from the forward position to the reverse position
The clutch pedal is interlockedly connected to the dog clutch.

[0006]

According to the present invention, the power of the engine can be transmitted to the traveling axle through the hydraulic continuously variable transmission and the gear type transmission to drive the work vehicle. Further, by depressing the clutch pedal, the clutch interposed between the hydraulic continuously variable transmission and the gear type transmission can be disconnected to enable the emergency stop of the work vehicle. Further, when performing a gear shift operation of the gear type transmission, the clutch is disengaged and the gear shift operation is performed.

Furthermore, write-free and work vehicle stepping on the clutch pedal when traveling at high speed with the traveling speed change lever to stop immediately, HST is returned to the neutral or low speed position. Therefore, when the depression of the clutch pedal is released, the work vehicle maintains the stopped state or restarts running at a low speed.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment in which the present invention is applied to a combine will be described with reference to the drawings. As shown in FIGS. 4 and 5, the combine 1 is a threshing device 5 having a handling drum 4 and the like on the left side of a body frame 3 having left and right crawler traveling devices 2 and 2.
Is mounted on the right front side of the threshing device 5.
a mounted on the engine 6, and a radiator 7 having a fan 7 a is mounted behind the engine 6.
A support frame 8a is fixed to the body frame 3 in front of the threshing device 5, and the pre-processing unit 8 including a weeding raising device, a cutting blade, a scraping transfer device, a deep transfer device, and the like is controlled by a hydraulic cylinder 8b. It is supported up and down freely. On the right side of the pre-processing unit 8, a cabin 10 in which a control unit 9 including a control seat 9a and the like are integrally provided is installed.

As shown in FIGS. 4, 5, and 6, a support frame 8 of the pre-processing unit 8 below the threshing device 5 is provided.
A counter case 11 is detachably fixed to the body frame 3 by bolts in the space between "a" and "a". An input shaft 12 supported by the counter case 11 is connected to an output shaft 6b of the engine 6 by a transmission shaft 14 having free joints 13 on both sides. Further, a pump 15 of a hydraulic continuously variable transmission and a working hydraulic pump 16 are detachably fixed to the counter case 11, and the power transmitted to the input shaft 12 is transmitted to a gear 12 a fixed to the input shaft 12. Is transmitted to the gear 18 fixed to the outer diameter of the hollow shaft 17, and the hollow shaft 17 is connected to a pump input shaft 15 a of a hydraulic continuously variable transmission by a spline portion provided at the inner diameter of the hollow shaft 17. The input shafts 16a of the hydraulic pumps 16 are fitted and driven. The other gear 19 fixed on the hollow shaft 17 meshes with a gear 20a fixed on the transmission shaft 20, the transmission shaft 20 extends toward the engine 6, and a threshing drive pulley 21 Is fixed. In addition, the transmission shaft 20 is covered by a holding cylinder 22,
One end of the holding cylinder 22 is fixed to the counter case 11 and the other end is fixed to the body frame 3 via a bracket 3a. Further, the threshing drive pulley 21 drives a pulley 23 located above by a belt 24. The transmission shaft 25 of the pulley 23 drives a bevel gear (not shown) provided in the gear box 5c of the threshing device 5, and finally rotates the handle shaft 5a. Reference numeral 24a is a tension clutch pulley that is connected to a threshing clutch lever (not shown) provided in the control section 9 to interrupt transmission to the threshing device 5.

Further, a hydraulic oil tank 26 is provided on the body frame 3 substantially at the center of the body in front of the threshing device 5. The hydraulic oil in this tank is guided by a low pressure hose 27 to a filter 28 (which is integrally fixed to the pump 15 of the hydraulic continuously variable transmission), and is supplied to a charge pump of the hydraulic continuously variable transmission. Although a detailed description of the hydraulic stepless transmission itself is omitted, a control arm 29 for changing the angle of the swash plate of the pump by a hydraulic servo mechanism is linked to a traveling speed change lever described later, and the arm 29 is neutralized. By operating from the position N to the forward side F or the reverse side R, the direction and the discharge amount of the pressure oil discharged from the high-pressure hoses 30 and 31 connected to the pump 15 are changed. A transmission case 32 supported by the body frame 3 is provided at a lower front portion substantially at the center of the body, and high-pressure hoses 30 and 31 are provided on the upper left side of the transmission case 32.
The motor 33 of the hydraulic continuously variable transmission that connects the other end of the motor is fixedly provided. The motor 33 receives the pressure oil from the pump 15 and stops or rotates forward or backward. Further, the hydraulic oil that has lubricated and cooled the pump 15 and the motor 33 by the charge pump is returned to the hydraulic oil tank 26 via an oil cooler (not shown) by a hose 34.

Next, the internal structure of the transmission will be described. As shown in FIGS. 1, 2 and 3, a motor 33 of a hydraulic continuously variable transmission is fixed to a transmission case 32. Output shaft 33a
Is connected to an input shaft 36 via a coupling 35 in the transmission case. A dog gear 39 which is slidably urged toward the input gear 38 by a spring 37 at all times is spline-fitted to the input shaft 36. Here, the dog gear 39 meshes with the internal teeth 38 a provided on one of the input gears 38, but the meshing can be broken by moving the dog gear 39 with the shifter 40 against the spring 37. power transmission to formula transmission is interrupted. In this embodiment, a dog clutch which can be configured at a low cost as described above is employed, but another clutch such as a hydraulic multi-plate clutch may be used.

In the following, a description will be given of a gear end transmission which constitutes a subtransmission. The input gear 38 meshes with a large-diameter tooth 42a of a gear 42 loosely fitted on an intermediate shaft 41, and a small-diameter tooth 42b of the gear 42 has a subtransmission shaft. The sub-transmission shaft 43 is driven by meshing with a gear 44 fixed to 43. A speed change gear 45 is spline-fitted slidably on the auxiliary speed change shaft 43, and a low-speed gear 46 and a medium-speed gear 47 are loosely fitted on the left and right sides. Therefore, by moving the transmission gear 45 by a shifter linked to the sub-transmission lever 9f provided on the control unit 9 and meshing the internal teeth 45a with the low-speed gear 46, the gear 48
, The intermediate shaft 41 is driven at a low speed. Similarly, the transmission gear 45 is moved so that the other internal tooth 45b is
7, the intermediate shaft 41 can be driven at a medium speed via the gear 49. When the intermediate shaft 41 is driven at a high speed, the speed can be changed by engaging the high-speed teeth 45c of the transmission gear 45 with the gear 50 fixed to the intermediate shaft 41.

The power appropriately shifted by the gear type transmission described above is transmitted to the lower shaft 51 by the intermediate gear 50.
And transmitted to a center gear and a side clutch gear provided on a steering shaft and left and right axles 53 and 54 in the same manner as in the conventional device, and traveled by sprockets 55 and 56 provided on the axle. The devices 2, 2 are driven. In addition, at the left end of the sub-transmission shaft 43,
Pretreatment transmission pulley 58 with one-way clutch 57 inside
Only the forward driving force of the traveling transmission is transmitted from the pulley 58 to the input pulley 61 of the pre-processing unit 8 via the belt 59 and the tension clutch pulley 60.

Among the constructions of the control unit 9 installed in the cabin 10, the constructions of the traveling speed change lever linked to the control arm 29 of the hydraulic continuously variable transmission and the clutch pedal linked to the dog clutch will be described below.
As shown in FIGS. 7 and 8, the control section 9 is provided with a clutch pedal 62 and a traveling speed change lever 9b. The clutch pedal 62 is supported on a fulcrum shaft 64 provided below the step 9e of the driver's seat 9a. A clutch wire 66 is connected to an arm 65 integrally connected to the base of the clutch pedal 62 by a pin 65b. Is fixed through. The other end of the clutch wire 66 is connected to a dog clutch shift arm 4 provided in the transmission case 32.
The wire 66 branches off midway and is linked to a running brake (not shown) provided on the transmission case 32. A roller 65 is rotatably supported on a shaft 65 a provided on the arm 65, and a cam 69 a of a cam plate 69 rotatably supported on a shaft 68 provided below the driver's seat 9 a is supported by the roller 67. Contact. An inner wire 70 is provided on the upper end of the cam plate 69.
And the outer wire 70a is connected to the control unit 9
Fixed to The other end of the wire 70, the long hole 71a (flexible hand engages the pin 9d projecting from the traveling shift lever 9b
(Step) is connected to the neutral return plate 71 (neutral return member) . Similarly, an inner wire 72 is fixed to the lower end of the cam plate 69, and an outer wire 72a is fixed to the control unit 9, and the other end of the inner wire 72 has a slot 73a (flexible means) . It is fixed to the neutral return plate 73 (neutral return member) .
Reference numeral 74 denotes a return spring of the clutch pedal 62 provided on the arm 65.

Next, as described above, the traveling speed change lever 9b has a pin 9d which engages with the neutral return plates 71 and 73 in the middle, and the center of a fulcrum shaft 75 provided at the lower portion of the traveling speed change lever 9b. It is configured to be tiltable back and forth against the brake device. A rod 9c linked to the control arm 29 of the hydraulic continuously variable transmission is connected to the base of the lever 9b. By tilting the traveling speed change lever 9b in the forward F or reverse R direction from the neutral position N, Arm 2 of hydraulic continuously variable transmission via rod 9c
9, the direction of the pressure oil discharged from the pump 15,
The motor 33 is driven to change the speed by changing the discharge amount.
Normally , when the clutch pedal 62 is not operated, the pin 9d provided on the traveling speed change lever 9b only moves in the long holes 71a, 73a (flexible means) of the neutral return plates 71, 73, and the traveling speed change lever 9b The gear is allowed to move and the gear can be freely shifted from the forward position to the reverse position. However, when the clutch pedal 62 is depressed, the arm 6
5 rotates and the roller 67 rotates the cam 69a of the cam plate 69.
Press. When the cam plate 69 rotates, the inner wires 70 and 72 are pulled, and the neutral return plates 71 and 73 move right and left in opposite directions to each other.
The traveling speed change lever 9a is returned to the neutral position N or a low-speed position as required through the pin 9d engaged with the ends of the a and 73a. (By adjusting the outer receptacles of the wires 70a, 72a, the return positions of the long holes 71a, 73a of the neutral return plates 71, 73 can be adjusted, and the return of the lever 9b can be selected to the neutral position or the low-speed position.)

In the above configuration, in order to perform the harvesting operation with the combine 1, the engine 6 is started, and the pre-processing unit 8 and the threshing device 5 are driven with the cutting clutch lever and the threshing clutch lever (not shown) being engaged.
Next, the operator tilts the traveling transmission lever 9b to the forward F side to start traveling. Then, at the time of turning or the like, the traveling speed change lever 9b is appropriately selected to be the forward F side or the reverse R side, and the traveling speed is appropriately increased / decreased by the traveling speed change lever 9b to perform work at an appropriate traveling speed. In this case, the power of the engine 6 is transmitted through the transmission shaft 14 to the counter case 1.
1 , and transmitted to a pump input shaft 15a of a hydraulic continuously variable transmission, and the pump 15 is driven by a motor 3 provided on a transmission case 32 at a speed set by a traveling transmission lever 9b.
3 is driven. Since the dog clutch in the transmission case 32 is connected, the transmission is transmitted to the lower transmission gear type speed change device. In the gear type transmission, the transmission gear 45 is previously shifted to a low speed or a medium speed position by an auxiliary transmission lever 9f provided in the control unit 9, so that the power transmitted through the gear type transmission is transmitted to the axles 53 and 54, The crawler traveling devices 2 and 2 rotate and the combine 1 travels.

Next, during operation, when it is desired to change the traveling speed from low speed to medium speed, or when shifting to traveling on the road, the clutch pedal 62 is depressed and the speed change gear 45 is moved to low speed, medium speed, Or shift to the high-speed position. In this case, the clutch pedal 62 shifts the dog gear 39 in the transmission case 32 against the spring 37 to disconnect the dog clutch. Thus rotational power to a neutral braking effect of the hydraulic stepless transmission is beyond that provided in transmission upstream side in the gear type transmission. Therefore, when the speed change gear 45 is shifted to the low speed, medium speed, or high speed position by the auxiliary speed change lever 9f, the speed change gear 45 of the gear type transmission becomes free to rotate and half-meshed with the low speed, medium speed, or high speed gear. It is possible to smoothly engage with each other without causing the like.

Further, in conjunction with the depressing operation of the clutch pedal 62, the traveling speed change lever 9b moves the forward F side and the reverse R side.
In any case, since the neutral return plates 71 and 73 return to the neutral or low-speed position, the dog gear 39 smoothly moves without generating gear noise even if the depressing operation of the clutch pedal 62 is released after the sub-shift operation. Input gear 38
In addition to being engaged with the dog clutch, the aircraft maintains a stopped state or starts at a low speed, so that the aircraft does not suddenly start and is safe. Similarly, by depressing the clutch pedal 62, the dog clutch can be disengaged and the aircraft can be stopped. Therefore, when the aircraft is to be stopped urgently due to an unexpected situation, the traveling speed change lever 9b is returned to the neutral position. The machine can be immediately stopped without waiting for the rotation of the motor 33 of the hydraulic continuously variable transmission to stop. Moreover,
Emergency braking is possible by applying the traveling brake by depressing the clutch pedal 62.

[0019]

As described above, according to the present invention, the power of the engine is transmitted to the axle via the hydraulic continuously variable transmission and the gear type transmission. In addition, the gear-type sub-shift operation can be performed by the sub-transmission lever, and the vehicle can travel in a wide speed range. Moreover, by depressing the clutch pedal, the clutch interposed between the hydraulic type continuously variable transmission and the gear type transmission can be disconnected and the work vehicle can be stopped urgently. I can deal with it. Further, when performing a gearshift operation of the gear type transmission, the gearshift operation can be performed by disengaging the clutch interposed between the hydraulic stepless transmission and the gear type transmission. since the rotational power to the hydraulic stepless transmission which is provided on the transmission upper side is not inferior neutral braking, speed change gear of the gear transmission system becomes its rotation free, smooth shifting without causing half-chewing like Can operate.

The clutch interposed between the hydraulic stepless transmission and the gear type transmission is a dog clutch, and the hydraulic stepless transmission is returned to a neutral or low speed position by depressing a clutch pedal. configuration in order to to
Thus, when the depression of the clutch pedal is released, the hydraulic continuously variable transmission stops or rotates at a low speed, so that the hydraulic continuously variable transmission can be smoothly engaged without generating dog gear gear noise or the like. In addition, even when the depression of the clutch pedal is released, the aircraft does not suddenly start and stops traveling or travels at a low speed, so that safe work can be performed.

In particular, in order to return the hydraulic continuously variable transmission to a neutral or low speed position by depressing the clutch pedal, the traveling speed change lever and the clutch of the hydraulic continuously variable transmission are used.
When the clutch pedal and the clutch pedal are not
Via a pair of neutral return members that allow the shifting operation of the speed lever
A very simple configuration in which the two neutral return members are operated in opposite directions by depressing the clutch pedal, the objective can be achieved regardless of whether the traveling speed change lever is on the forward side or the reverse side. Therefore, it is possible to provide a practical device whose operation is reliable, inexpensive and has few failures.

[Brief description of the drawings]

FIG. 1 is an AA showing a part of a transmission case.
It is sectional drawing.

FIG. 2 is a BB showing a part of a transmission case;
It is sectional drawing.

FIG. 3 is a left side view of the transmission case.

FIG. 4 is a left side view showing a part of the combine.

FIG. 5 is a front view showing a main part of the traveling transmission.

FIG. 6 is a plan sectional view showing a motor part of the counter case and the hydraulic continuously variable transmission.

FIG. 7 is a side view showing a traveling speed change lever and a clutch pedal.

FIG. 8 is a side view showing a state in which a clutch pedal is depressed.

[Explanation of symbols]

Speed change gear 62 clutch pedal 71 neutral return plate of the output shaft 9b traveling shift lever 14 the transmission shaft 15 hydraulic motors 39 dog gear 45 gear transmission system of the pump 32 the transmission case 33 HST continuously variable transmission apparatus 6b engine (Neutral return member) 71a Long hole (flexible means) 73 Neutral return plate (neutral return member) 73a Long hole (flexible means)

──────────────────────────────────────────────────続 き Continued from the front page (56) References JP-A-62-88626 (JP, A) JP-A-56-124564 (JP, U) JP-A-54-28817 (JP, U) JP-A 58-124 41624 (JP, U) Fully open 49-82406 (JP, U) Fully open 58-97070 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F16H 47/02-47 / 04 F16H 59/00-63/48 B60K 17/00-17/08 B60K 20/00-20/08

Claims (1)

(57) [Scope of request for utility model registration] 1. A hydraulic continuously variable transmission for powering an engine,
In a working vehicle that is transmitted to a traveling axle via a gear type transmission, the output shaft of the engine is connected to a pump of a hydraulic continuously variable transmission, and provided on a motor and a transmission case of the hydraulic continuously variable transmission. And a gear type transmission through a dog clutch, and by operating a traveling speed change lever, the hydraulic continuously variable transmission is moved to a forward acceleration / deceleration position,
The traveling speed change lever and a clutch lever provided on a control unit are provided so that they can be operated to a neutral position and a reverse acceleration / deceleration position, respectively.
And Dar connected via a pair of neutral return member, the class <br/> When the depression operating Tchipedaru both neutral return member is operated in the opposite direction, engaging the travel gear lever neutral or low speed position of the speed change state While it is configured to return
When the clutch pedal is not operated,
The travel shift lever is in the forward position regardless of the
A flexible means is provided to allow the shifting operation from the reverse position to the reverse position ,
The traveling transmission of a work vehicle, wherein the clutch pedal is interlocked with the dog clutch.