JPH0627539B2 - Work vehicle gear shift operation device - Google Patents

Description

The present invention relates to a gear shift operation device for an operator such as a tractor and a wheel loader.

(Prior Art) For example, an agricultural tractor has a low speed both during work and when traveling on the road and has a maximum speed of 15 to 30 km / H, but it is now required to travel at high speed when traveling on the road. A transmission having an overdrive mechanism has been devised.

As this prior art, there is one disclosed in Japanese Patent Laid-Open No. 62-204037, in which the power of the propulsion shaft is not passed through the main speed change mechanism and the auxiliary speed change mechanism by putting the main speed change operation lever in the overdrive position. Further, it is configured to be transmitted to the pinion shaft of the drive wheel differential device via the overdrive mechanism.

(Problem to be Solved by the Invention) In the above-mentioned conventional technology, since the overdrive operating means is interlocked with the main gearshift operating means, when the main gearshift operating lever is moved to the overdrive position, the main gearshift mechanism becomes neutral. However, if you forget to set the auxiliary shift operation lever to the neutral position,
The rotation of the pinion shaft is transmitted to the auxiliary transmission mechanism and the super-reduction mechanism in front of it. Since these are deceleration mechanisms, if they are input from the output side, they act as speed-up mechanisms, which may damage the bearings and seals.

The present invention provides an interlocking mechanism for returning the auxiliary shift operation lever to the neutral position when the main shift operation lever is in the overdrive state so that the overdrive power is not reversely input to the auxiliary transmission mechanism. A first object is to provide a device.

Further, the present invention makes it possible to operate the overdrive mechanism with the auxiliary gearshift operation lever so that the overdrive state does not occur unless the auxiliary gearbox mechanism is brought into a neutral state, so that the overdrive power is not reversely input to the auxiliary gearbox mechanism. It is a second object of the present invention to provide a gear shift operation device for the worker.

(Means for Solving the Problem) A specific means for achieving the first object of the present invention is to operate a main transmission operation means on a traveling system that transmits power of a propulsion shaft to a pinion shaft of a drive wheel differential device. And a high speed traveling system including an overdrive mechanism operated by the overdrive operating means are formed, and a main traveling operation is performed. In the gear shift operation device of the operator, the operation lever of the means is such that the overdrive mechanism can be operated after the main gear shift mechanism is in the neutral state, between the main gear shift operation lever and the operation lever of the auxiliary gear shift operation means. That is, there is provided interlocking means for returning the auxiliary shift operating lever to the neutral position when the main shift operating lever is brought into the overdrive state.

Further, a concrete means for achieving the second object of the present invention is a main transmission mechanism and a sub-transmission mechanism operated by a main transmission operating means in a traveling system for transmitting power of a propulsion shaft to a pinion shaft of a drive shaft differential device. A shift operating device for a worker, comprising a working traveling system including an auxiliary shift mechanism operated by a shift operating means and a high speed traveling system including an overdrive mechanism operated by overdrive operating means. The operating lever of the operating means is such that the overdrive mechanism can be operated after the auxiliary transmission mechanism is in the neutral state.

(Operation) In FIGS. 1 and 2, the operation lever 56 of the main gearshift operation means 10
Is shifted from the neutral position N to the overdrive position OD, the shift gear 54 slides through the shifter 59, the overdrive small gear 53 is connected to the transmission shaft 35, and the power of the propulsion shaft 18 is transmitted to the bevel pinion shaft 39. And the rear wheels rotate at high speed. At the same time, the swinging motion of the operating lever 56 is transmitted to the operating lever 64 of the auxiliary shift operating means 11 via the swinging body 71 and the returning body 72 of the interlocking means 69, and the auxiliary shift operating lever 64 moves to the high position H or If it is in the low position L, return it to the neutral position N,
The subtransmission mechanism 6 is brought into a neutral state.

In FIG. 3, when the auxiliary shift operation lever 64 is moved from the high position H or the low position L to the overdrive position OD, the operation lever 64 passes through the neutral position N, so that the auxiliary transmission mechanism 6 is in the neutral state. After that, the overdrive mechanism 9 is operated.

(Example) Hereinafter, the Example of this invention is described based on drawing.

In the first embodiment shown in FIGS. 1 and 2, reference numeral 1 denotes a four-wheel drive type agricultural tractor transmission, which is roughly classified into a main clutch 2, a dual transmission mechanism 3, a main transmission mechanism 4, and an ultra-reduction mechanism 5. The sub-transmission mechanism 6, the rear-wheel differential device 7, the front-wheel drive clutch 8, the overdrive mechanism 9, the speed change operation means 10 and 11 of each mechanism, and the like, and a traveling system and a PTO system.

The main clutch 2 is a traveling clutch 13 and a PTO clutch 14
The power of the engine (not shown) is transmitted from the traveling clutch 13 to the dual transmission mechanism 3 via the double shaft cylinder shaft 15 by a double clutch having

The dual speed change mechanism 3 is a high and low two-speed speed change mechanism that combines a hydraulic clutch 16 and a planetary gear speed reduction mechanism 17, and sets the power of the cylinder shaft 15 to a high speed in a directly connected state and a low speed via the planetary gear speed reduction mechanism 17. To the propulsion shaft 18.

The main transmission mechanism 4 moves forward between the propulsion shaft 18 and the counter shaft 19
Gears 20, 21, 22, 23, 24, 25 and 1st gear reverse 26, 27, 28
The forward first speed gear 21 and the reverse gear 27 are selectively connected to the counter shaft 19 by the shift gear 29, and the forward second speed gear 23 and the third speed gear 25 are respectively connected by the shift gear 30.

The ultra-reduction mechanism 5 includes the counter shaft 19 and an intermediate shaft 32 behind the counter shaft 19.
Gears 33 and 34 are respectively provided in and, and integral gears 36A and 36B are loosely fitted on a transmission shaft 35 that is arranged in parallel with both shafts 19 and 32.
3 and gear 36A, gear 34 and gear 36B are in constant mesh, and the intermediate shaft 32
By engaging the upper shift gear 37 with the gear 33,
The intermediate shaft 32 is directly connected to the counter shaft 19, and by engaging the shift gear 37 with the gear 34, the rotation of the counter shaft 19 is decelerated and transmitted to the intermediate shaft 32.

The sub-transmission mechanism 6 is an intermediate shaft 32 and a bevel pinion shaft behind it.
The gear 40 fixed to the intermediate shaft 32 is always meshed with the integral gear 41A on the transmission shaft 35, and is fixed between the intermediate shaft 32 and the bevel pinion shaft 3
The upper shift gear 42 is slidable between a position where it is meshed with the integrated gear 41B and a position where it is spline-fitted to the intermediate shaft 32.
The low speed rotation is transmitted to the bevel pinion shaft 39 by meshing with the integrated gear 41B, and the high speed rotation directly coupled to the intermediate shaft 32 is transmitted to the bevel pinion shaft 39.

The bevel pinion of the bevel pinion shaft 39 is a bevel gear.
The rear wheel differential device 7 is in mesh with 43 and constitutes a part of the rear wheel diff device 7. The bevel pinion shaft 39 and the transmission shaft 35 are always linked by gears 44 and 45 which are normally meshed.

The transmission shaft 35 constitutes a front-wheel drive system, and an intermediate transmission shaft 46 is arranged in front of the transmission shaft 35. Power can be freely connected to and disconnected from the shafts 35, 46 by a front-wheel drive clutch 8. The transmission shaft 46 and a front drive shaft 47 provided in parallel therewith are interlocked by gears 48, 49, and the power of the front drive shaft 47 is transmitted to a front wheel drive diff device (not shown) via an external drive shaft 50. Transmitted.

The dual mechanism 3 to the rear wheel differential device 7 constitutes a traveling system, particularly a working traveling system, and can obtain a working speed required for rotary work or plow work.
The dual transmission mechanism 3 may not be provided, a forward / reverse switching mechanism may be provided, and the sub transmission mechanism 6 and the super speed reduction mechanism 5 may be replaced with each other. However, the side closer to the bevel pinion shaft 39 is referred to as an auxiliary transmission mechanism.

The overdrive mechanism 9 that forms a high-speed traveling system includes a large gear 52 that is integrally provided with the third speed gear 25 of the main transmission mechanism 4,
It has a small gear 53 loosely fitted on the transmission shaft 35, the transmission shaft 35, a shift gear 54 that engages the small gear 53 with the transmission shaft 35, and the gears 44 and 45 that are normally meshed.

Therefore, the power of the propulsion shaft 18 is transmitted to the gears 52 and 53 via the gears 24 and 25 which are normally meshed, is transmitted to the transmission shaft 35 by the engaging action of the shift gear 54, and the gear teeth 44 and 45 which are normally meshed. At the same time as being transmitted to the rear wheel differential device 7 via the front wheel drive clutch 8, it is also possible to transmit to the front drive shaft 47.

The large and small gears 52 and 53 have a speed increasing mechanism, and the transmission shaft 35
Can be rotated with respect to the propulsion shaft 18 at a constant or increased speed.

Operating lever of the main shift operating means 10 for operating the main transmission mechanism 4
56 is two shift gears 29, via two shifters 57, 58
In addition to selectively sliding 30, the shift gear 54 can also be operated via the shifter 59.
It also serves as the operating lever of the main shift guide plate 61.
In the guide groove 62 of, the overdrive position OD is formed in addition to the first, second and third speeds of the work traveling system, and the operating lever 56 moves from the state where the work traveling system is in the neutral position to the overdrive position OD. It is supposed to enter.

The sub-transmission operating means 11 for operating the sub-transmission mechanism 6 linearly operates one operating lever 64 to shift gears via the shifter 65.
Only by linearly sliding 42, a high speed position H, a neutral position N and a low speed position L are formed in series in a guide groove 67 of the guide plate 66.

Interlocking means 69 is provided between the main gear shift operating lever 56 and the sub gear shift operating lever 64. The interlocking means 69 has an L-shaped rocking body 71 pivotally supported by a pivot 70 and a returning body 72 guided linearly by a guide body (not shown).

The oscillating body 71 can come into contact with the operation lever 56 in the neutral position when the first arm portion 71a is in contact with the stopper 74 by the tension spring 73 (the position indicated by the dashed line in FIG. 2). To the overdrive position OD,
It is swung in the direction of arrow 75 against the spring 73. The second arm portion 71b is provided with a return member 72 via a pin 77 penetrating the elongated hole 76.
And swinging causes the return body 72 to slide in the direction of arrow 78.

The return body 72 has a triangular hole 79 formed therein. The maximum portion L of this triangular hole 79 is substantially the same as the length of the guide groove 67, the minimum portion S is of a size that fits the operating lever 64 substantially, and when the maximum portion L corresponds to the guide groove 67, The operating lever 64 is a guide groove
When the minimum portion S can freely move in the 67 and corresponds to the guide groove 67, the operation lever 64 is forcibly arranged in the neutral position N. Therefore, regardless of whether the operating lever 64 is in the high position or in the low position, when the return body 72 slides in the direction of the arrow 78, the operating lever 64 is forcibly returned to the neutral position N by the inclined surface of the triangular hole 79. .

In the second embodiment shown in FIG. 3, the guide plate 66 of the auxiliary shift operating means 11 is provided with an overdrive guide rod 81 in addition to the guide groove 67, and the operating lever 64 is provided with a guide groove.
It is possible to operate from 67 neutral position N to overdrive position OD.

Although not shown, the guide groove of the main shift operating means is H-shaped, no overdrive position is provided, and the auxiliary shift operating lever 64 is provided with a shifter 65 for operating the shift gear 42 of the auxiliary transmission mechanism 6 shown in FIG. , Shift gear of overdrive mechanism 9
The shifter 59 for operating 54 can be operated alternatively.

In the second embodiment, the auxiliary transmission mechanism lever 6 is brought into the overdrive position OD to bring the auxiliary transmission mechanism 6 into the neutral state, and the integrated gear 41 is reversely driven even if the bevel pinion shaft 39 is overdriven. There is no such thing. If it is forgotten to put the main transmission mechanism 4 and the super-reduction mechanism 5 in a neutral state, the engine power is transmitted to these mechanisms 4 and 5, but the rotation speed is the reduced rotation speed during work traveling. It is the same as, and it is not the reverse input that further speeds up the overdrive rotation.

(Effects of the Invention) According to the present invention described in detail above, when the operating lever 56 or 64 is moved to the overdrive position OD, the auxiliary transmission mechanism 6 is in a neutral state, so the overdrive power transmitted to the pinion shaft 39 is transmitted. Is not reversely input to the sub-transmission mechanism 6, and therefore the bearings, seals, etc. of the sub-transmission mechanism 6 and the super-reduction mechanism 5 in front of the pinion shaft 39 are not rotated at ultra-high speed,
It is possible to eliminate noise of parts of each mechanism, wear of contact parts, seizure and the like.

[Brief description of drawings]

1 and 2 show a first embodiment of the present invention. FIG. 1 is a diagrammatic view of a transmission, FIG. 2 is a plan view of interlocking means, and FIG. 3 is a second embodiment of the present invention. It is a top view of the guide plate of the auxiliary shift operation lever shown in FIG. 1 ... transmission device, 2 ... main clutch, 4 ... main transmission mechanism, 5 ... super reduction mechanism, 6 ... subtransmission mechanism, 7 ... rear wheel differential device, 8 ... front wheel drive clutch, 9 ... … Overdrive mechanism, 10 …… Main shift operating means, 11 …… Sub shift operating means, 18 …… Propulsion shaft, 35 …… Transmission shaft, 39 …… Bevel pinion shaft, 52 …… Large gear, 53 …… Small Gears, 54 ... Shift gears, 56 ... Main shift operating levers, 59 ... Shifters, 60 ... Overdrive operating means, 61 ... Main shift guide plates, 62 ...
Guide groove, 64 …… auxiliary shift operation lever, 67 …… guide groove,
69 …… Interlocking means, 71 …… Swinging body, 72 …… Returning body.

Claims (2)

[Claims] 1. A traveling system for transmitting the power of a propulsion shaft to a pinion shaft of a drive wheel differential device is provided with a main speed change mechanism operated by a main speed change operation means and an auxiliary speed change mechanism operated by an auxiliary speed change operation means. A work traveling system and a high-speed traveling system having an overdrive mechanism operated by the overdrive operating means are formed, and the operation lever of the main gearshift operating means can operate the overdrive mechanism after the main gearshift mechanism is in the neutral state. In the gear shift operation device for the operator, the auxiliary gear shift operation lever is located between the main gear shift operation lever and the operation lever of the auxiliary gear shift operation means when the main gear shift operation lever is in the overdrive state. A gear shift operation device for an operator, characterized in that interlocking means for returning to the back is provided. 2. A traveling system for transmitting power of a propulsion shaft to a pinion shaft of a drive wheel differential device is provided with a main speed change mechanism operated by a main speed change operation means and an auxiliary speed change mechanism operated by an auxiliary speed change operation means. In a gear shift operating device for a worker having a work traveling system and a high-speed traveling system provided with an overdrive mechanism operated by an overdrive operating means, an operating lever of the auxiliary gearshift operating means sets the auxiliary gearshift mechanism to a neutral state. A shift operating device for a work vehicle, wherein an overdrive mechanism is operable after the start.