JPS6069351A - Hydraulic transmission system for driving work vehicles - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention IIi provides a plurality of fluid pressure cylinders that individually turn on and off a plurality of friction clutches for speed change, and a speed change pulp that switches the operating state of these fluid pressure cylinders. To provide a fluid pressure type transmission for driving a working vehicle that is constructed so that it can be easily operated with a light operating force that is sufficient to change the transmission pulp.

Conventionally, in the above-mentioned transmission, when the transmission pulp reaches the recommended transmission position, the cylinder operates quickly and the clutch is forced into the idle position. On the other hand, on smooth surfaces such as roads, unpleasant vibrations of the aircraft occur almost as soon as the modification is completed. There were drawbacks that occurred.

An object of the present invention is to obtain the advantage of suppressing gear shift deterioration during gear shifting on rough terrain.

The purpose is to suppress the occurrence of vibrations that occur when shifting gears on smooth ground.

The characteristic configuration of the above-mentioned hydraulic transmission system for driving a working vehicle is that the fluid pressure supplied from the fluid pressure pump to the fluid pressure cylinder in response to the clutch engagement operation is transferred from the fluid pressure pump to the fluid pressure cylinder. A pressure increasing mechanism that gradually increases the discharge pressure is provided in a state that is automatically reset to an operable state when the speed change pulp is located between adjacent clutch engagement operation positions, and the pressure increasing mechanism is set to an operable state. The purpose of the present invention is to provide a mechanism for switching between the two modes, and its functions and effects are as follows.

In other words, on rough terrain, by allowing the gradual pressure increase @ mechanism to fully operate, the cylinder will operate quickly and the clutch will engage rapidly.On smooth ground, the gradual pressure increase By allowing the mechanism to operate, the cylinder operates slowly and the clutch gradually engages. Therefore, on rough terrain,
It is possible to keep the traveling device from being in a non-driving state during gear shifting to a very short period of time, and to reduce the speed drop.
On smooth ground, the gearshift pulp is at the clutch engagement level.
The transmission of power to the traveling equipment (U) is gradually carried out even after the machine is turned off, so that vibrations are prevented, and the vehicle can travel efficiently and comfortably for work and transportation.

Embodiments of the present invention will be described below with reference to all the drawings.

As shown in FIG.
) is attached so that it can be rotated and slidably operated integrally with the ft-J coupled transmission gear (5a).
is transmitted to the main transmission for traveling (61), and the output of this main transmission bag opening (6) is transmitted to a pair of steering clutches (7a), (
7b), a pair of left and right crawler traveling drive shafts (8
A traveling transmission device for a combine harvester is configured so that separate transmission wJ and transmission stop can be transmitted to a) and (8b). The output shaft (91) shown in the figure is for transmitting power to the reaping section.

The main transmission +81 includes the auxiliary transmission (
5) 1st forward speed gear (lO) and 8th forward speed gear that are always engaged with the 1st and 2nd output gears (5b) * (5c) and 8th forward speed gear + llI 'i first transmission shaft [121 attached to be freely rotatable. , a second forward speed gear 03 that is always engaged with the second output gear (5c), and a reverse gear (141) that is always engaged with the first forward speed gear (10).
It is attached to the FA so that it can rotate freely, and the first transmission shaft Q2+ saw n
a transmission gear (12a) that rotates integrally with the second transmission shaft α; and a transmission gear (15a) that rotates integrally with the second transmission shaft α.
) are always engaged with the input gears -06) of both the steering clutches (7a) and (7b), and when off, forward 1st to 8th gear +10), 031, 1l1
1 and reverse gear 〇41 and the first transmission shaft (12
1 or the 2nd transmission shaft (Iω), a multi-plate transmission friction clutch (17a) or (x7b) or (17c) or (1'7d)' is provided, and these clutches (
Hydraulic cylinder (18a) or (18b) or I/'1(
18c) Also, Fi (18d) 2 is prepared in a state where it is biased to the clutch disengage side, and the clutch (17a) is operated by operating the cylinder (18a) or 48a) with seven rotary speed change pulps 091. ) to 17d) are operated individually to obtain the desired transmission state Ia or full speed in the forward motion of eight forward speeds and one reverse speed.

As shown in the second cause, the first oil passage (20) is connected to the variable speed pulp (191), and the artificially selected pear opening/closing valve 1211 (Ji
If the second oil passage (22) is connected to the accumulator □
□□) is connected. Then, the variable speed pulp Q9+ is moved to the forward transmission position (forward/distal fEf(Fl)),
Forward distal gi (p,), forward 3rd speed 1i & (Fs)
, slightly advanced fM (R), the first oil road (
20) to the pump port, connect each cylinder (18a) fx 'vz in the middle position.
The drained oil from L (18d) is supplied to each of the clutches (17a) and 17d) together with the oil from pump +2=ll for cooling and lubrication, and then returned to the tank and filled with the oil in the oil drain passage. Further % Mt to connect 1 oilway spider
+ Forward 1st speed distal p,) and forward 2nd speed edict (F,) between LI
%J and IBI between the 2nd forward speed position [F,] and the 3rd speed position, the second oil passage no. 111 is configured to be connected to the oil drain passage (26) together with the pump boat, As the pulp Q9 is operated from the neutral position to the forward l speed position (pl) or the reverse position (9), the accumulator (23) moves the pump H7) to the part of the supply flow to the ring WrM8iL, Pump Q-sawa supply hydraulic pressure to cylinder (2
% and opening/closing valve 121) so as to gradually adjust to the discharge pressure from The accumulator discharges the M accumulated pressure oil to the oil drain path through the second oil passage (22) and the variable speed pulp α9)2, and the variable speed pulp (R9) is then transferred to the transmission position CF, ) or CF2).
Or, when (F,)K is reached, the gradual pressure increase operation can be performed and the oil drain fall break is automatically reset.
Then, when the on-off valve (l) is closed, the variable speed pulp (
Even if 19) corresponds to the transmission position tA) or (Ill), the accumulator (23) cannot discharge the pressure oil that has accumulated when the variable speed pulp (191) is at the first forward speed position 11 (Fl). .

The variable speed pulp field is in the forward 1st gear position (F, ) and the forward 2nd gear position (
F2) and @Shin8 Distal Association (F3), respectively.
VCC is absorbed so that the gradual pressure increase operation is no longer performed even if the voltage is increased.

When switching from a neutral state to a forward speed state or a reverse motion, the cylinder operating speed at the initial stage of clutch engagement becomes low.

The structure is such that sudden start is prevented, and the clutch (1
7a) or (17b) or (17c), so that the forward speed can be changed while the cylinder operating speed is kept at full low speed at the initial stage of clutch engagement, and clutch (17a) or (1'7L+) or (17c). ) is made so that the cylinder operating speed at the initial stage of the clutch engagement operation can be manually changed to a state in which the forward speed can be changed from a high speed to a constant forward speed by using the on-off valve l).

FIG. 3 shows another example of the gradual pressure increase configuration and the configuration in which fL is switched between the active state and the non-active state, and a relief valve is installed between the pump (24J and variable speed pulp (R9)). 6) Fully connect the actuator Cη that changes the relief pressure of this relief pulp (26) to the first oil path (28
) to the variable speed pulp 091 via the second oil passage (9) and the eighth oil passage (30) of the manually operated idle closing valve (211), Shift PULZO f191'i, the second oil passage (
29) '(rConnect the second oil passage (29) to the oil drainage passage (sha) at each of the transmission positions (5) or (Bl) so as to connect to the oil drainage passage (sha). The variable speed pulp (R91 is configured so that each transmission position acid (Fz)*(F
g)-(Fs)s(When present in each of R1, Bonpre4
The pressure oil supplied from J gradually increases the relief pressure of the actuator or the relief valve, and the relief valve (2) increases the hydraulic pressure supplied from the pump (24) to the cylinder. The pump (24) is operated so as to gradually increase the discharge pressure, that is, at the beginning of the clutch engagement operation.
A part of the pressure oil supplied to the cylinder is returned to the tank,
Modulation ta, i! to gradually reduce the amount of return. :(311'< ta) Then, when the variable speed pulp 091 is opened to the neutral position, the actuator (27) is filled with the pressure oil supplied from the pump (24) and the variable speed pulp. The oil is discharged to the oil drain passage 0 through α9), thereby relieving the pressure increase operation of the relief valve (26). Then, the on-off valve (2+1 'k
11? ], when the variable speed pulp α9) reaches the transmission position (Al or (Ill K), the actuator (27) transfers the pressure oil supplied from the pump to the eighth oil path (30) and the variable speed pulp. (19) Modulation mechanism c31) by discharging oil evenly through the oil drain path
is automatically reset to the operable state, and the modulation mechanism (311) can be activated during forward gear shifting.If the on-off valve is fully closed, the gear shifting pulp 119) will be able to operate. Rank @Mon (person) Mata Iri
! Even if it becomes Bl.

If the discharge from the actuator ρη is impossible, the leaf-Jl (26) will be kept high and the leaf compression will be maintained sharply.
The operation of 4i Gll becomes unstable.

4. Figure 4 shows another example of a configuration for switching the accumulator (23) between an operating state and a non-operating state. A control mechanism that detects the rotation speed of the power generation port based on the rotation speed of the power generation port and automatically closes the opening/closing valve (21) only when the detected rotation speed is less than or equal to the set speed. ! : It is a setting. That is, when the running resistance exceeds the set value, the accumulator I23
) is configured to automatically switch to the inactive state. still.

C141 shown in the figure is a switch for controlling the controller 1 (331).

In the case shown in FIG. 5, the on-off valve side 1) is linked to the reaping section (to) via the interlocking mechanism 1k (to), and the mowing p! , and is configured to automatically switch to open when the parts (branches) are raised to the non-working level.

That is, when the machine is put into a non-working state, the operating state of the valve (1) is suddenly and automatically switched, and in the case of the one shown in FIG.
Operation lever c18I of the auxiliary transmission for traveling (5)
The VC is connected so that the sub-speed gear (5) is automatically opened only when the speed is high, medium, or low. The accumulator (231) is configured so that when the system is set to a non-working high-speed system, the operating state of the accumulator (231) is suddenly automatically changed to #y'J.

The invention can also be applied to various work vehicles such as tractors.

[Brief explanation of drawings]

The drawings show an example of an uninvented hydraulic system for driving a work vehicle, with Figure 1 being a transmission system diagram, Figure 2 being a hydraulic circuit diagram, and Figure 3 being a hydraulic circuit diagram of a different example, and Figure 3 being a hydraulic circuit diagram of a different example. Figures 4 to 6 are schematic diagrams of another embodiment of the opening/closing valve fabrication structure. (17g) or 17c) ...-clutch,
(18a) or 18c)...Cylinder,
(191...th... variable speed pulp. Cutting 1)......switching mechanism, +231, ! 11
... Gradual boosting mechanism. H...pump, (p, ), o-t), o-s)
...Input operation order %tA), tB)...
...Between the entry operation positions.

Claims (1)

[Claims] ■ A plurality of transmission friction clutches (17a) or 1
7c) A plurality of fluid pressure cylinders (18a) fx IIs L (18c) are provided, and these fluid pressure cylinders (18a) are turned on and off individually (18a).
This is a fluid pressure type transmission device for running a commercial vehicle, which is equipped with a speed change valve aα for switching the operating state of the hydraulic cylinder (18) from the fluid pressure pump example when the clutch is engaged.
a) to 18c) that gradually increases the fluid pressure supplied to the fluid pressure pump (1) to the discharge pressure from the fluid pressure pump (1);
23) or (311-1) The above-mentioned shift valve αm is located between the adjacent clutch operation positions (Fs) * (F2) s (F3), (2 in each of B1 and cannot be operated. A fluid pressure type transmission device for traveling of a work vehicle, which is provided with an automatic reset operation in a state in which the pressure increases (or a mechanism η that switches G11 to an inoperable state). ■ The pressure increase mechanism (23) is the 6fl cylinder (18a
) The bag according to claim 0, which is an accumulator for storing a portion of the fluid B, which is supplied to the fluid Hlc). (2) The device U0 according to claim 0, wherein the pressure increasing mechanism Cl1l returns a part of the fluid supplied to the cylinder (18a) to 18c) to the tank.