JPH0547896Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a linkage structure between the auxiliary transmission clutch and the input clutch of the transmission, which can suitably perform main transmission in multiple stages including reverse movement.

Generally, in a combine harvester transmission, the input shaft that inputs the engine power is mounted on the top of the transmission case, and the power transmitted from this input shaft is transmitted through the main transmission, which is spline-fitted to the input shaft so that it can only slide freely. The transmission is transmitted through an appropriate slide gear to an elevation sub-shift hydraulic clutch on the downstream side that is capable of switching between elevation and low sub-shifts, and then to a pair of left and right axles at the bottom.

By the way, in this type of transmission, the power from the engine is transmitted by a belt to an input pulley fixed to the protruding end of the input shaft protruding from the transmission case, and the power is transmitted to the input shaft. Since the slide gear rotates in unison with the input shaft, which has a high rotational speed, the slide gear is slid in the direction of this axis and selectively engages the corresponding gear on the downstream side, allowing multiple stages including reverse movement. When performing the main gear shift, there were problems such as gear noise.

Therefore, in this invention, the input shaft and the input pulley are separated, and they are interlocked and connected by an input clutch that can be disconnected. The input clutch is also disconnected to cut off the drive to the input shaft, reducing the rotational speed of the shaft, so that there is no resistance to the engagement and disengagement of gears on the same axis due to the rotation of the input shaft with no driving force and only inertial force. In addition, the above-mentioned drawbacks have been addressed by providing a linkage structure between the auxiliary transmission clutch of the transmission and the input clutch, which enables smooth gear shifting without gear squeal.

Hereinafter, a case in which a specific embodiment of this invention is applied to a combine harvester will be described in detail.

First of all, this mission is mission case 1.
The protruding end of the input shaft 2, which is mounted on the upper part of the input shaft 2, and the input pulley 3, which inputs the power of the engine (not shown), form a multi-plate clutch 4 consisting of a plurality of friction plates, etc.
The input shaft 2 is interlocked with an input hydraulic clutch 4 which can be connected and disconnected via the input shaft 2, and large and small slide gears 5 and 6 for performing main speed change are spline-fitted to the input shaft 2 so as to freely slide only. The large and small slide gears 5 and 6 are each independently slid and displaced by left and right transmission hawks 8 and 9 that slide on the transmission shaft 7, and the large and small slide gears 5 and 6 are both connected to the input shaft 2. When the small slide gear 9 is slid to the right via the right shift hawk 9 from the neutral position (see Fig. 1) approaching the intermediate position, the low-speed passive gear fixedly disposed on the transmission shaft 10 first shifts. On the other hand, through the forward 1st speed F1 position meshed with 11,
When the large slide gear 5 is slid leftward from the neutral position via the left transmission fork 8, the second forward speed is first engaged with the medium speed passive gear 14, which is also fixedly disposed on the transmission shaft 10. After passing through the F2 position, the removable engaging claws 5a, 15a protruding from the opposing surfaces of the forward intermediate gear 15 and the large slide gear 5, which are loosely fitted to the left end of the input shaft 2, engage with each other. transmission shaft 1 via intermediate gear 15.
When the large slide gear 5 is slid to the right from the F3 position, it returns to the original neutral position through the F2 position. Return to position. In addition, the left and right transmission hawks 8 and 9 are normally operated as follows.
The fixing ring 17 is biased to the intermediate position of the speed change shaft 7 by the force of springs 8a and 9a.

Next, in this manner, the input shaft 2 is connected to the transmission shaft 10.
The power transmitted to the transmission shaft 10 is transmitted through large and small transmission gears 18,
After being transmitted to the high and low auxiliary transmission passive gears 18 and 19, the rotation of the high and low auxiliary transmission passive gears 13 and 20 is transmitted in the forward direction to the high and low auxiliary transmission passive gears 13 and 20, which are constantly meshed with the transmission gears 18 and 19.
The high-speed secondary transmission driven gear 13 is selectively transmitted from the high-speed secondary transmission shaft 12 to the secondary transmission gear 23 at the intermediate position of the secondary transmission shaft 12 via a pair of left and right high-low secondary transmission hydraulic clutches 21, 22 which are switchable between high and low secondary transmissions H and L. When the small slide gear 6 and the high secondary transmission passive gear 13 are engaged at the reverse R position as described above, the high reverse speed RH is transmitted to the secondary transmission gear 23 via the high secondary transmission hydraulic clutch 21, while the low secondary transmission hydraulic clutch 2
2, the torque is transmitted to the auxiliary transmission gear 23 as the reverse low speed RL.

The power transmitted to the sub-transmission gear 23 passes through a pair of left and right side clutches (not shown) disposed downstream from the sub-transmission gear 23.
The power is transmitted to a pair of left and right axles (not shown) provided at the bottom of the transmission case 1.

By the way, the input hydraulic clutch 4 has an input pulley 3, which is composed of a pulley part 3a and a clutch cylinder part 3b, rotatably fitted to the protruding end of the input shaft 2, and is a clutch piston that connects and disconnects the multi-plate clutch 4a. 4b is slidably fitted to the outer circumferential surface of the input shaft 2, and is also slidably fitted to the inner circumferential surface of the clutch cylinder portion 3b. And the clutch cylinder part 3b
is the circumferential groove 2a of the input shaft 2 so as not to hinder rotation.
The clutch piston 4b is locked by an appropriate number of locking screws 24 and is detachable from the outside, and when the clutch piston 4b is cut, the multi-plate clutch 4 is held by a spring 4c.
The pressure oil is biased in the cutting direction of a and is sent from the oil passage 2b drilled in the input shaft 2.
It is configured to slide against a spring 4c to connect the multi-plate clutch 4a. If a disc spring 4d or the like is interposed between the multi-disc clutch 4a and the clutch piston 4b, a preload is applied to the multi-disc clutch 4a even when the input hydraulic clutch 4 is disconnected, and the input shaft 2 The input pulley 3 is rotated to some extent by the force of the disc spring 4d.
Since this rotation is transmitted from A disc spring 4 provides a preload to the multi-plate clutch 4a to obtain a rotation slightly larger than the minimum rotation of the pump 25.
d is used). Further, when the multi-plate clutch 4a is connected, oil seeped from the clutch piston 4b is guided into the transmission case 1 either directly or through a passage. In addition, mission case 1
Oil passage 2b of input shaft 2 that is farthest from the oil level inside
Since pressure oil is introduced into the tank, it can be expected to function as forced lubrication if an oil filler port is opened in a suitable place such as a metal part to avoid the effect of pressure drop.

The height/low sub-shift hydraulic clutches 21, 22 include a clutch cylinder 21a fitted to the sub-shift shaft 12,
22a is fixed to both ends of the auxiliary transmission gear 23, and clutch pistons 21c, 22c for connecting and disconnecting the multi-plate clutches 21b, 22b are slidably fitted on the outer peripheral surface of the auxiliary transmission shaft, and the clutch cylinders 21a, A multi-plate type of conventional structure is used which is slidably fitted to the inner circumferential surface of 22a. And the clutch piston 21c, 2
2c is biased in the cutting direction of the multi-plate clutches 21b, 22b by springs 21d, 22d during cutting, and is connected to the forward oil passages 12a, 1 bored in the sub-shift shaft 12.
The pressure oil sent from 2b causes the spring 21 to
d and 22d to connect the multi-disc clutches 21b and 22b. At this time, the clutch pistons 21c, 22c
The oil leaking from the tank is led to the common return oil path 12c.

Next, in order to operate the input hydraulic clutch 4 and the height/low sub-shift hydraulic clutches 21 and 22, as shown in FIG. By switching the shift operation lever 27 of the control valve 26, a neutral state in which both the high and low sub-shift hydraulic clutches 21 and 22 are disconnected, and as described above, oil is supplied from the outgoing oil passage 12a and the multi-disc clutch 21b is connected. When the high sub-shift hydraulic clutch 21 is connected to the high sub-shift H state, oil is also supplied from the outgoing oil passage 12b,
The low sub-shift hydraulic clutch 22 which connects the multi-disc clutch 22b is selectively switched to the low sub-shift L state, high and low sub-shifts H and L are performed via neutral, and the high-low sub-shift hydraulic clutch 21, 22
During each of the high and low sub-shifts H and L, the oil that returns from these common return oil passages 12c is sent from the oil passage 2b of the input shaft 2 to the input hydraulic clutch 4, the clutch piston 4b operates, and the multi-disc clutch is activated. 4a
is connected, and the input hydraulic clutch 4 is also connected. This means that when the high/low auxiliary transmission hydraulic clutches 21 and 22 are in the neutral position, no oil is sent to the input hydraulic clutch 4, so this input hydraulic clutch 4 is also in a disconnected state, and at this time, the input pulley 3 Power is not transmitted from the input shaft 2 to the input shaft 2, and the large and small slide gears 5 and 6
, the rotation of the large slide gear 5 or the small slide gear 6 is slid and alternatively engaged with the downstream passive gears 11, 13, 14, etc., and in this embodiment, including reverse movement. 4-speed main gear R-F1--F2-F3 is possible.
First, move the gear shift operation lever 27 as shown in the figure.
Operate the high and low sub-shifts H and L so that they are above the neutral position, then perform the main shifts R-F1--F2-F3, and then move the high and low sub-shifts to H or low at the changed position of the main shift. A shift pattern that allows switching to the sub-shift L can be formed.

In addition, in the figure, 28 is a relief valve that maintains the pressure at a constant pressure, 29 and 29 are check bubbles that may be provided, 30 is a guide plate for the speed change operation lever 27, and 31 is a speed change that is interlocked and connected with the speed change operation lever 27. It is an arm.

As is clear from the above description, according to this invention, the operation system for the height and low auxiliary transmission clutches 21 and 22 is adjusted so that the input clutch 4 is disengaged in conjunction with the disengagement of both the height and low auxiliary transmission clutches 21 and 22. Since the input clutch 4 is connected to the operation system, when the height and low sub-shift clutches 21 and 22 are both disengaged and in the neutral state, the input clutch 4 is also disengaged, so that the input shaft is disconnected from the input pulley 3. The power transmission to the input shaft 2 is cut off, and the large and small slide gears 5, which rotate together with the input shaft 2,
6's rotation slows down, resulting in low rotation with only inertia force and no driving force, and there is no gear noise that occurred when the input pulley was fixed to the input shaft as in the past, and the large and small slide gears 5 and 6 By independently slidingly displacing the input shaft 2, the downstream corresponding passive gears 11, 13,
14 etc., suitable main shift R,
Can perform F1, F2, and F3. At this time, a multi-plate clutch 4 is connected from the input pulley 3 to the input shaft 2.
a. Since the drag torque is transmitted through the clutch piston 4b etc., the large and small slide gears 5 and 6
There will be no situation in which the peaks of the gears collide with the peaks of the passive gears 11, 13, 14, etc., and then the phase does not change and the main gear cannot be changed.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the essential parts of a transmission implementing this invention, FIG. 2 is an operating circuit diagram of an input hydraulic clutch and a height/low sub-shift hydraulic clutch, and FIG. 3 is a shift pattern diagram of a shift operating lever. Symbol, 1...Mission case, 2...Input shaft, 3...Input pulley, 4...Input clutch,
4a...Multi-plate clutch, 5, 6...Slide gear, (5...Large slide gear, 6...Small slide gear), 21, 22...Height/low sub-shift clutch.

Claims (1)

[Scope of utility model registration request] The shaft is mounted on a transmission case 1, and within this transmission case 1, slide gears 5 and 6 that can be changed to multiple main gears R, F1, F2...Fn including reverse are fitted so as to freely slide only. An input shaft 2 provided on the input shaft 2 and an input pulley 3 for inputting engine power are interlocked and connected via an input clutch 4, and the transmission power of the input shaft 2 is distributed downstream. In this transmission, the input clutch 4 is disengaged when the high/low sub-transmission clutches 21, 22 are selected to be neutral. An interlocking structure for an input auxiliary transmission clutch for a transmission, characterized in that the operation system of the height and low auxiliary transmission clutches 21 and 22 is linked with the operation system of the input clutch 4.