JPH03292223A - Inching device for torque converter vehicle - Google Patents

Abstract

PURPOSE:To control a supply quantity of the operating oil to a wet type single plate clutch to adjust the connection condition thereof freely, and to perform any inching travelling stably by operating an inching operating means freely under the condition that a wet type multiplate clutch for shifting forward drive and reverse is connected. CONSTITUTION:The operating oil sucked from a tank 2 by an oil pump 1 is supplied to a converter circuit 4, a selector circuit 5 and an inching circuit 6 through a regulator 3. When a selector lever 9 is shifted, for example, to forward drive or reverse, all of the operating oil supplied to a selector valve 7 is fed to a wet type multiplate clutch 8, and the clutch 8 is connected perfectly to transmit the power to driving wheels. Under this connection condition, when an inching pedal 12 is operated perfectly, all of the operating oil supplied to an inching valve 10 is drained without to be fed to a wet type single plate clutch 11, and the clutch 11 is not connected. Power transmission to the wet type multiplate clutch 8 is thereby cut off perfectly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an inching device for a torque converter vehicle equipped with a wet clutch.

[Prior Art] Conventionally, this type of inching device has been installed in a torque converter (torque converter) vehicle and equipped with a clutch pack consisting of a wet multi-plate clutch disc that serves both forward and forward switching and inching. Are known.

For example, as shown in FIG. 3, hydraulic oil sucked up from a tank 22 by an oil pump 21 is adjusted to a specified pressure by a regulator (hydraulic regulator) 23, and then a converter circuit for operating a torque converter is used. 24, and a clutch circuit 26 for operating a wet multi-disc clutch pack 25 that serves both for forward/forward switching and for inching.
and will be supplied.

In the case of normal operation without inching operation, that is, when the inching pedal 27 is not operated,
All of the hydraulic fluid sent to the inching valve 28 of the clutch circuit 26 is supplied to the clutch pack 25 through the selector valve 29.

The selector valve 29 is controlled in response to the operation of a selector lever 30 for switching forward and backward movement.

As shown in FIG. 4, inside the clutch pack 25,
The piston 31 is operated by one hydraulic oil, the plurality of clutch disks 32 and the plurality of driven plates 33 are integrally connected without slipping, and power is taken out from the clutch gear 34.

On the other hand, in the case of an inching operation in which the inching pedal 27 is operated, a portion of the hydraulic fluid sent to the inching valve 28 is transferred to the selector valve 29 depending on the amount of operation.
It is sent to the clutch pack 25 through the. Inside the clutch pack 25, some of the hydraulic oil causes the piston 31 to operate slightly, but slippage occurs between the clutch disc 32 and the driven plate 33, and only a portion of the power is transferred to the clutch gear. It is output from 34.

[Problems to be Solved by the Invention] However, in the prior art described above, the clutch pack 25 is made of a wet multi-plate in order to serve both the forward/reverse switching and inching functions. For this reason, the clutch pack 2
Due to the structure of 5, the inching pedal 2 is
7 is slightly changed and the oil pressure or oil amount to the clutch pack 25 changes slightly, the clutch disc 32
There was a tendency for the connection state between the drive plate 33 and the drive plate 33 to suddenly change. As a result, it becomes difficult to stably perform arbitrary inching travel according to the amount of operation of the inching pedal 27, resulting in a problem of poor inching operability.

This invention has been made in view of the above-mentioned circumstances, and its purpose is to stably perform arbitrary inching travel according to the amount of operation of the inching operation means, and to improve inching operability. An object of the present invention is to provide an inching device for a torque converter vehicle that is capable of inching.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a torque converter that changes the speed and transmits the output of the engine;
In an inching device for a torque converter vehicle, the inching device is equipped with a wet clutch for both forward/reverse switching and inching, which turns on and off output transmission from the torque converter to the drive system, and a hydraulic oil supply means for supplying hydraulic oil to the wet clutch. The clutch is a wet multi-disc clutch dedicated to forward/reverse switching, and a wet single disc clutch dedicated to inching is provided to switch on and off the output transmission from the torque converter, and the connection state of the wet single disc clutch can be arbitrarily changed. The clutch includes an inching operation means that is operated for adjustment, and a hydraulic oil control means that controls the amount of hydraulic oil supplied to the wet single-plate clutch in accordance with the amount of operation of the inching operation means.

[Operation] According to the above configuration, by arbitrarily operating the inching operation means with the wet multi-disc clutch for forward/reverse switching engaged, the hydraulic oil control means operates the wet multi-disc clutch in accordance with the amount of operation. The amount of hydraulic oil supplied to the plate clutch is controlled, and the connection state of the wet single plate clutch is arbitrarily adjusted.
Inching travel is performed. In addition, since the clutch dedicated to inching is a wet single-plate clutch, even if the oil pressure or oil amount supplied to the wet single-plate clutch changes during inching operations, the connection state will not change suddenly.
An appropriate half-clutch state is maintained and stable inching travel is performed.

[Example] Hereinafter, an example embodying the present invention will be described in detail based on the drawings.

FIG. 1 is a schematic diagram showing a hydraulic circuit of an inching device in a torque converter vehicle of this embodiment. Hydraulic oil sucked up from a tank 2 by an oil pump 1 serving as a hydraulic oil supply means is adjusted to a specified pressure by a regulator (hydraulic regulator) 3, and then transferred to a converter circuit 4 for operating a torque converter. The signal is supplied to a selector circuit 5 for forward switching and an inching circuit 6 for inching.

Hydraulic oil supplied from the regulator 3 to the selector circuit 5 is sent via the selector valve 7 to a wet multi-disc clutch 8 dedicated to forward/reverse switching. The selector valve 7 is controlled in accordance with the operation of a selector lever 9 for switching forward and backward movement. The wet multi-disc clutch 8 includes a plurality of clutch discs and a plurality of driven plates, which are connected to each other to transmit power.

On the other hand, the hydraulic oil supplied from the regulator 3 to the inching circuit 6 is sent to a wet single-plate clutch 11 exclusively for inching via an inching valve 10 serving as a hydraulic oil control means. The inching valve 10 controls the amount of hydraulic oil supplied to the wet single disc clutch 11 in response to the amount of operation of an inching pedal 12 as an inching operation means operated to arbitrarily adjust the connection state of the wet single disc clutch 11. is controlled. In addition, the wet type single plate clutch 11 has two parts facing each other.
It is equipped with two clutch discs, and power is transmitted by connecting them to each other.

FIG. 2 is a schematic diagram showing the power transmission mechanism of the torque converter vehicle of this embodiment. The output of the engine 16 is transmitted to the drive wheels 18 via a torque converter 17, a wet single-plate clutch 11 dedicated to inching, and a wet multi-plate clutch 8 dedicated to forward/reverse switching. Further, the oil pump 1 is driven by an engine 16. As shown in FIG. 1, hydraulic oil from the oil pump 1 is supplied to the torque converter 17, the inching valve 10, and the selector valve 7 via the regulator 3. Furthermore, inching valve 10
The hydraulic oil supplied to the selector valve 7 is sent to the wet single-disc clutch 11, and the hydraulic oil supplied to the selector valve 7 is sent to the wet multi-disc clutch 8.

Next, the operation of the inching device in the torque converter configured as described above will be explained.

Now, when the selector lever 9 is switched to the neutral position, all the hydraulic oil supplied to the selector valve 7 is drained without being sent to the wet multi-disc clutch 8 dedicated to forward/reverse switching, and each disc of the clutch 8 is drained. becomes disconnected. As a result, power transmission to the drive wheels 18 is completely cut off.

On the other hand, when the selector valve 9 is switched to forward or reverse, all the hydraulic oil supplied to the selector valve 7 is sent to the wet multi-disc clutch 8, and each disc of the clutch 8 is completely connected. As a result, the drive wheel 18
Power is transmitted to.

In this connected state of the wet multi-plate clutch 8,
When the inching pedal 12 is not depressed, all the hydraulic oil supplied to the inching valve 10 is sent to the wet single-plate clutch 11 exclusively for inching, and the same clutch 1
Both disks of 1 are fully connected. Thereby, power can be transmitted to the wet multi-disc clutch 8.

Furthermore, when the inching pedal 12 is fully depressed, all of the hydraulic oil supplied to the inching valve IO is drained without being sent to the wet single-plate clutch 11, and both discs of the clutch 11 become disconnected. As a result, power transmission to the wet multi-disc clutch 8 is completely cut off.

On the other hand, when the inching pedal 12 is depressed by only a part of the total depression amount, only a part of the hydraulic oil supplied to the inching valve IO is sent to the wet single-plate clutch 11.
Both disks of the clutch 11 are in a half-connected state (half-clutch state). As a result, only a portion of the power is transmitted to the wet multi-disc clutch 8.

As described above, the clutch device of this embodiment is provided with a wet type multi-plate clutch 8 dedicated to forward/reverse switching, and a wet single plate clutch 11 dedicated to inching for switching on and off the output transmission from the torque converter 17. Therefore, even if the oil pressure or oil amount supplied to the wet single-plate clutch 11 changes slightly during the inching operation, the connection state will not change suddenly, and the clutch 11 will remain in a moderately half-clutch state. This allows stable inching to be performed. In other words, arbitrary inching travel can be stably performed depending on the amount of stroke of the inching pedal 12, and inching operability can be improved.

Note that this invention is not limited to the above embodiments,
For example, although the above embodiments have only explained the basic schematic configuration of the hydraulic circuit, part of the configuration may be changed as appropriate without departing from the spirit of the invention, such as by appropriately changing the detailed configuration of the circuit. It may also be carried out.

[Effects of the Invention] As detailed above, according to the present invention, arbitrary inching travel can be stably performed according to the amount of operation of the inching operation means, and inching operability can be improved. Demonstrates excellent effects.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a hydraulic circuit of an inching device in a torque converter vehicle according to an embodiment of the present invention, and FIG. 2 is a schematic diagram showing a power transmission mechanism of the torque converter vehicle. FIG. 3 is a schematic diagram showing a hydraulic circuit of a conventional inching device, and FIG. 4 is a sectional view showing a part of the clutch pack. In the figure, l is an oil pump as a hydraulic oil supply means, 8 is a wet multi-disc clutch, 1o is an inching valve as a hydraulic oil control means, 11 is a wet single disc clutch, and 12 is an inching pedal as an inching operation means. .

Claims (1)

[Claims] 1. A torque converter that changes the speed and transmits the output of the engine, a wet clutch that is used for forward/reverse switching and inching that turns on and off transmission of the output from the torque converter to the drive system, and a hydraulic oil supply that supplies hydraulic oil to the wet clutch. In the inching device for a torque converter vehicle, the wet clutch is a wet type multi-disc clutch exclusively for forward/reverse switching, and a wet type exclusively for inching is provided separately for switching on/off the output transmission from the torque converter. a single-disc clutch, an inching operation means operated to arbitrarily adjust the connection state of the wet single-disc clutch, and an amount of hydraulic oil supplied to the wet single-disc clutch in accordance with the amount of operation of the inching operation means. An inching device for a torque converter vehicle, comprising a hydraulic oil control means for controlling.