JPS63152751A - Hydraulically operated gear transmission - Google Patents

Abstract

PURPOSE:To promote the reduction of synchronizing time of a subtransmission, by connecting a small contour transmission member of a hydraulic clutch to the side of an input shaft. CONSTITUTION:A hydraulic clutch C, which controls disc plates 25, 26 being forced to come into press contact by a pressure of oil, exists interposing between an output shaft 8 from a main transmission A of gear type, operating a speed change control by the action of an oil hydraulic actuator, and an input shaft 9 for a subtransmission B of gear type operating a speed change control by the action of an oil hydraulic actuator. While the hydraulic clutch C operates so as to perform the disconnecting action immediately before both the actuators are actuated. In this transmission, a small contour transmission member 23 of the hydraulic clutch C is connected to a side of the input shaft 9. By this constitution, synchronizing time of the subtransmission can be reduced.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a large number of disc plates provided inside a cylindrical clutch case, and a small diameter transmission member provided outside the clutch case. A hydraulic clutch, in which a large number of disc plates are arranged alternately, and which press and operate these disc plates by hydraulic pressure, is connected to an output shaft from a gear-type main transmission that is operated to change speed by the operation of a hydraulic actuator, and A hydraulically operated gear shift interposed between an input shaft of a gear-type sub-transmission device that is operated to change gears by actuation of an actuator, and configured to disconnect and operate the hydraulic clutch immediately before actuation of both hydraulic actuators. Regarding equipment.

[Conventional technology]

An example of a hydraulically operated gear transmission configured as described above is the one disclosed in Japanese Patent Application Laid-Open No. 61-6'028, in which the hydraulic clutch is disengaged and operated immediately before a gear change operation. The hydraulic system is constructed in a sequence operating type so that the hydraulic clutch is operated to a transmission state immediately after a gear shift operation, and the gear shift operation can be performed without disengaging the main clutch.

[Problem that the invention seeks to solve]

In addition, in the transmission of the cited reference, the gear transmission section is constructed in a synchromesh type so that a smooth shift operation can be performed in each part of the main and sub-transmission devices.

Also, when comparing the main transmission and the auxiliary transmission, in the hydraulic gear transmission configured as described above, a member with a relatively large moment of inertia, such as a reverse gear, is connected to the auxiliary transmission. Therefore, when the auxiliary transmission operates to shift, the time required from the start of the shift to the completion of the shift tends to be longer than the time required to operate the main transmission, which has a relatively small moment of inertia. When changing gears, the vehicle body is in a non-driving state for the time required for synchronization, so there is room for improvement.

In particular, in the cited example, when the hydraulic clutch is disengaged, the clutch case having a relatively large diameter portion is connected to the auxiliary transmission, which increases the time required for synchronization.

An object of the present invention is to reduce the time required for shifting the sub-transmission device as much as possible by rationally arranging the hydraulic clutch.

[Means for solving problems]

A feature of the present invention is that in the transmission having the above configuration, the small-diameter transmission member of the hydraulic clutch is connected to the input shaft side, and its functions and effects are as follows.

[For production]

If the above characteristics are configured as shown in FIGS. 1 and 2, for example, the small-diameter transmission member (23) of the hydraulic clutch (C) will be connected to the side. ! CB) side, the synchronization time of the sub-transmission device (B) can be shortened compared to the transmission device of the above-mentioned reference.

〔Effect of the invention〕

Through a relatively simple modification of changing the orientation of the hydraulic clutch, the synchronization time of the sub-transmission system can be shortened, and the time the vehicle runs without drive can also be shortened.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

As shown in Figures 2 and 3, power from the engine (1) is transferred to the transmission case (3) via the main clutch (2).
), the transmission power from the transmission case (3) drives the front and rear wheels (4), (5), and the external power take-off shaft (6) protruding from the rear end of the transmission case (3) A transmission system of an agricultural tractor is configured to drive the agricultural tractor.

As shown in these figures, the mission case (3) has a synchromesh type transmission that changes the power from the drive shaft (7) in four stages and transmits it to the first shaft (8), which is an example of an output shaft. The main transmission (8), the multi-disc hydraulic clutch (C) interposed between the first shaft (8) and the second shaft (9) as an example of an input shaft, and the A synchromesh sub-transmission device (B) transmits power to the third shaft (10) by changing the speed to two forward speeds and one reverse speed, and the power from the third shaft (10) is transmitted to the rear wheels (5). ), the differential mechanism (11), the third
A gear interlocking mechanism (13) that transmits power from the shaft (10) to an output shaft (12) for the front wheels (4), and an input shaft (7).
) is internally equipped with a constant mesh type PTO transmission (D), etc., which changes the power from (14) is equipped with a one-way clutch (15), and power from the output shaft (12) is transmitted to the front wheels (4) via the intermediate shaft (16) and differential mechanism (17).

In the transmission system of the agricultural tractor, the two transmission sleeves (18) and (19) of the main transmission (A) are operated, and the forward transmission sleeve (20) of the auxiliary transmission (B) is operated.
Each operation is performed by a hydraulic actuator (18a).

(19a), (20a), and these hydraulic actuators (18a), (19a), (2
0a), the hydraulic clutch (
The hydraulic system is configured in a sequence operating type so that the hydraulic clutch (C) is operated to the transmission state immediately after the gear shift operation is performed, and the gear shift operation is performed without disengaging the main clutch (2). It will be done.

As shown in FIG. 1, the hydraulic clutch (C) has a first
A needle bearing (22) is externally fitted onto the shaft (8) via a spline portion (21s), and a needle bearing (22) is fitted onto the second shaft (9).
a clutch case (21) that is externally fitted through the clutch case (21), and a cylindrical part (21a) that is externally fitted to the second shaft (9) via the spline part (23s) and that is inside the clutch case (21).
), the small diameter transmission member (23) is externally fitted through the ball bearing (24), and the large diameter part (21) of the clutch case (21).
a number of disk plates (25) supported by 21b);
..., these disk plates (25)..., a large number of disk plates (26), which are arranged alternately and supported by the small diameter transmission member (23), and these disk plates (25)...・.

(26)... A hydraulic piston (27) that presses and operates;
These disk plates (25)..., (26)...
and a spring (28) that biases the two in the direction of separating them.

Further, the hydraulic clutch (C) has front and rear wall portions (3a).

(3b), and when assembling the transmission case (3), the hydraulic clutch (C) is assembled in advance, and the first shaft (8) is inserted into the transmission case (3).
After installing the hydraulic clutch (C) into the first shaft (8),
) so that the shaft end of the first shaft (8) and the wall part (
Of 3a) and 3b, the distance (S) from the rear part (3b) is set to such an extent that the hydraulic clutch (C) can be inserted.

As shown in Fig. 4, the hydraulic speed change operation system includes a hydraulic pump (31), a speed change valve (32), and the three hydraulic actuators (18a), (19a), (2).
0a) Three sequence valves (18v) that are constructed integrally with each other and change the pilot pressure when activated.
, (19v), (20v), Sequence valve (Bv) that changes biloft pressure during forward/reverse switching operation
), a hydraulic pump (31), a pressure regulating mechanism (33) interposed in the oil passage between the hydraulic clutch (C), and a logic valve mechanism (
34), hydraulic actuators (18a), (19a),
(20a) When each operates, the sequence valve (1
8v), (19v).

(20v) The hydraulic clutch (C) is once disengaged by the change in the pilot pressure from each of the hydraulic clutches (C), and is then operated to a transmission state.

[Another example]

In addition to the embodiments described above, the present invention can also be applied to, for example, a system in which the hydraulic speed change operation is configured by feedback using a sensor or the like.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the hydraulically operated gear transmission according to the present invention, in which FIG. 1 is a sectional view of a mission case showing the arrangement position of the hydraulic clutch, FIG. 2 is a sectional view of the hydraulic clutch, and FIG. 3 is a sectional view of the transmission case. FIG. 4 is a diagram showing the transmission system of the agricultural tractor, and FIG. 4 is a hydraulic circuit diagram showing the speed change operation system. (8)...Output shaft, (9)...Input shaft, (21)...Clutch case, (23)...
...Small diameter transmission member, (25). (26)... Disc plate, (A)...
...Main transmission, (B)...Sub-transmission, (
C)...Hydraulic clutch.

Claims (1)

[Claims] A large number of disk plates (25) provided inside a cylindrical clutch case (21), and a large number of disks provided outside a small diameter transmission member (23) installed inside the clutch case (21). The plates (26)... are arranged alternately, and these disk plates (25)...
. , (26) . . . with an output shaft (8) from a gear-type main transmission (A) that is operated to change speed by the operation of a hydraulic actuator;
It is interposed between the input shaft (9) of the gear type sub-transmission device (B) which is operated to change gears by the operation of the hydraulic actuator, and the hydraulic clutch (C) is operated to disengage immediately before the operation of both hydraulic actuators. A hydraulically operated gear transmission configured as such, wherein a small diameter transmission member (23) of the hydraulic clutch (C) is connected to the input shaft (9) side.