JPS6227300B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a forward and backward multi-stage transmission used in power working vehicles for agriculture, civil engineering, and the like.

More specifically, a multi-speed forward/reverse movement system in a mobile agricultural machine configured to perform traveling speed changes through cooperation between a first transmission mechanism G that switches between a forward state and a reverse state, and a second speed change mechanism A that performs multiple speed changes. This relates to transmissions.

When the first transmission mechanism G and the second transmission mechanism A are used to perform multi-stage traveling transmissions, if both transmission mechanisms are operated using two separate shift operation levers, the operation becomes complicated and it is difficult to perform a quick shift operation. At the same time, there is a risk that operational errors may occur easily.

The present invention has been made with the above-mentioned circumstances in mind, and relates to a forward/reverse multi-speed transmission mechanism for a mobile agricultural machine that allows both transmission mechanisms to be operated accurately and quickly.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

Figure 1 shows a cross-sectional view of the inside of the transmission case M, where 5 is a transmission wheel from the engine, 6 is a drive shaft,
7 and 7' are hydraulic pumps, G is a first transmission mechanism with a hydraulic clutch, and 9 is a second shaft for driving the front and rear wheels.

Hydraulic clutch devices C and C' are respectively disposed above the transmission in the path of the first transmission mechanism G equipped with a hydraulic clutch. Oil is supplied from the hydraulic pump 7 to the oil grooves 11, 11' at the end of the first shaft 10 through the directional control valve V, and from the oil grooves 11, 11', the oil is passed through the oil passage of the first shaft 10 to the hydraulic clutch device C. , C', and both devices C and C' are hydraulically operated.

Gear G2 of intermediate shaft 8 and gear 12 are meshed with drive gear G1 fixed to drive shaft 6, gear G3 fixed to intermediate shaft 8 is meshed with loosely fitted gear 12' on first shaft 10, and gear G1→ Gear G2 → Intermediate shaft 8 → Gear 1
2'→clutch device C'→first shaft 10 and the power transmitted is rotation for reverse movement.

On the other hand, it is directly transmitted from gear G1 to gear 12,
The gear 12 is connected to the first shaft 10 via the clutch device C.
The configuration is such that the power transmitted to is rotation for forward movement.

A mechanical second speed change mechanism A with a speed change gear selection sliding type is provided at a portion of the second shaft 9 in the lower transmission position.

The upper shaft 13 of the second shaft 9 has three large, medium and small gears 1.
4, 14', and 14'' are fitted and locked, the gear 15 loosely fitted to the second shaft 9 is always engaged with the gear 14'', and the two-gear transmission gear 15 is connected to the second shaft 9 with a spline 16. While being engaged, the shifter fork 3 is configured to be movable. The large and small gears 15a and 15b in the transmission gear 15 are the gears 14' and 1
4, and the large-diameter gear 15a of the transmission gear 15 is configured to engage with the side engaging portion 15''a of the gear 15'' in a freely fitting and removable manner.

The speed change guide plate B provided in the fuselage part F has a first
A second gear that allows gear shifting operation when the gear shifting mechanism G is in a neutral state.
A neutral groove 2 in the second operation direction for performing the speed change operation of the speed change mechanism A is formed. Then, in a direction perpendicular to the second operation direction in which the second transmission mechanism A is operated,
Three transmission grooves 4, 4', and 4'' are formed in the first operating direction for operating the transmission mechanism G, respectively.

Then, the transmission groove 4 along the first operating direction is
4' is for 2nd speed, and 4'' is for 3rd speed.

In addition, the neutral groove 2 in the second shift operation direction and the shift grooves 4, 4', 4'' along the first shift operation direction are interlocked, and one shift operation lever 1 that can move within the connected groove is inserted. It is composed of

A cylindrical metal 1a is fitted to the support rod 17 so that the base of the operating lever 1 can rotate freely around the support rod 17. The shift operating lever 1 is configured to be able to move within the neutral groove 2 in the first operating direction while rotating around the support rod 17. One end of the interlocking rod 19 is connected to an arm 18 fixed to the cylinder metal 1a, and the other end of the interlocking rod 19 is rotatably connected to an arm 21 fixed to a rotation shaft 20 mounted on the transmission case M. ing. A shifter rod 22 is fixed to the inner end of the rotating shaft 20, and the shifter rod 22 is engaged with the head of the shifter fork 3 movably mounted on the shifter shaft 23.

When the shift operation lever 1 is moved within the neutral groove 2 and positioned at the center of the shift grooves 4, 4'' on both sides, and at the center of the shift groove 4' which is the intermediate position, the shifter fork 3 is interlocked. The configuration is such that the speed change gear 15 is moved to perform gear changes from 1st speed to 3rd speed.

Also, one end of the support rod 17 has a shaft cylinder 1 in the orthogonal direction.
7' is integrally formed. The shaft cylinder 17' is engaged and fixed to a support shaft 24 rotatably supported on the body portion F. The support shaft 24 has universal joints 25, 25'.
Connecting one end of the transmission shaft 26, 26' with
An arm 28 is fixed to the other end of the transmission shaft 26' supported by the metal 27. A fork 28' at the tip of the arm 28 is engaged with a tip pin portion 29 of the spool S projecting laterally of the direction control valve V. 4F, 4R, 4'F, 4'R, 4'', which are both ends of the gear shift grooves 4, 4', 4''.
When the spool S is moved so as to be positioned at either F or 4''R, the spool S is pushed or pulled by the rotation of the arm 28 in conjunction with the movement, thereby clutching the hydraulic clutch devices C and C'. Configure it to operate automatically.

When performing a gear shift operation, if the operating lever 1 is located in the neutral groove 2 along the second operating direction and positioned at the front, rear, or intermediate position, the interlocking rod 19 will move in the direction of the arrow A as it rotates in the direction of the arrow A. At the same time, the shifter rod 22 rotates in the direction of arrow C, and the shifter fork 3 is operated to move the transmission gear 15, changing the second shaft 9 from 1st to 3rd gear.
It is operated to perform variable speed drive up to the maximum speed.

To move the aircraft forward, rotate the operating lever 1 in the direction of arrow
F, 4'F, 4''F, the transmission shafts 26, 26' rotate in conjunction with the operation, and the arm 2
8 is rotated to operate the spool S, the hydraulic clutch device C is operated to engage the clutch, the second shaft 9 is rotated, and the front and rear wheels are rotated forward.

Shift operations from the first to the third forward speed are performed while the gears are placed in the respective shift grooves 4, 4', and 4'' from the neutral groove 2.

When moving the aircraft backwards, the operating lever 1 is rotated from the neutral groove 2 in the direction of the arrow H, and the ends 4R, 4', and 4'' of the transmission grooves 4, 4', and 4'' along the first operating direction are rotated.
4'R, 4''R, the spool S is operated in the opposite direction by rotating in the opposite direction to the above, and the hydraulic clutch device C' is operated to engage the clutch, causing the second shaft 9 to rotate in the reverse direction. Rotate the wheel backwards.

While the gears are placed in the neutral grooves 4, 4', and 4'', gear shifting operations from reverse 1st speed to 3rd speed are performed, respectively.

As described above, the present invention provides a speed change operation configured to perform a traveling speed change through cooperation between a first transmission mechanism G that switches between a forward state and a reverse state, and a second transmission mechanism A that performs a multi-stage speed change. The device is a device in which one gear shift operating lever 1 is operated in one direction from a neutral state N along a first operating direction to enter a forward state, and by operating one gear shift operating lever 1 in the other direction from a neutral state N, it is set in a reverse state. Since the first transmission mechanism G is configured to be freely operable in a switching mode, and the second transmission mechanism A is configured to be freely operated by operation along a second operation direction different from the first operation direction of the speed change operation lever 1, This has the following effects.

That is, by operating one shift operation lever 1 in two different directions, the first shift mechanism G and the second shift mechanism A can be operated more accurately and quickly than when operating with two shift operation levers. This made it possible to operate the system.

Second, the first transmission mechanism G is operated by operating the transmission operating lever 1 in the first operating direction, and the second transmission mechanism A is operated by operating the transmission operating lever 1 in the second operating direction. , the first transmission mechanism G
The direction of operation for the second transmission mechanism A is always constant and easy to understand, and the speed change operation can be carried out smoothly without causing any operational errors.

Thirdly, in the first operation direction of the shift operation lever 1, operating from the neutral position to one side switches to the forward drive state, and operating from the neutral position to the other side switches to the reverse drive state. This has the advantage that it is easy for the operator to intuitively recognize the gear change state relative to the operating position of the operating lever 1.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the transmission case, FIG. 2 is a front view of the main part, FIG. 3 is a side sectional view of a part thereof, and FIG. 4 is a plan view of the speed change guide. C, C... Hydraulic clutch device, A... Mechanical second transmission mechanism, B... Speed change guide plate, G... First transmission mechanism with hydraulic clutch, V... Directional control valve,
1... Speed control lever, 2... Neutral groove along the first operating direction, 3... Clutch shifter, 4, 4',
4″...speed change groove along the first operating direction.

Claims (1)

[Claims] 1. A first transmission mechanism G that switches between a forward state and a reverse state, and a second transmission mechanism A that performs a multi-speed shift.
This is a speed change operation device configured to perform a traveling speed change in cooperation with The first transmission mechanism G is configured to be operable in such a manner that it can be switched to the reverse state by operating it in the other direction from the state N, and the first transmission mechanism G can be operated in a second operating direction different from the first operating direction of the shift operating lever 1. A speed change operation device in a forward/reverse multi-stage transmission mechanism, characterized in that the second speed change mechanism A is configured to be freely operable.