JPS61184135A - Control section in power transmission - Google Patents

Abstract

PURPOSE:To prevent a vehicle from abruptly starting upon starting of an engine, and to aim at making the restarting operation of the vehicle smooth after stall of the engine, by providing such an arrangement that a control device inhibits hydraulic pressure from being fed to a gear shift control valve when an engine is manipulated to be started if the speed change valve has been set to be in the power transmission condition. CONSTITUTION:A control device in a power transmission device has a gear shift control valve V1 which feeds hydraulic oil from a hydraulic pump P, selectively to hydraulic cylinder sections 18a-23a, and a clutch control inching valve V3 which relieves supplied hydraulic oil in accordance with the depression of an inching pedal 30. In this arrangement, an electromagnetic adjusting valve V2 which is controlled by a valve controller 31 is disposed between the above- mentioned valve V1 and the hydraulic pump P. This valve V2 cuts off the supply of hydraulic oil in association with a control device 34 when a first detector 32 detects such that the above-mentioned valve V1 is set to be in the power transmission condition and a second detector 35 detects the manipulation of the engine for restarting the latter.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an operating section for a power transmission, in which a speed change operating valve for the power transmission is connected to a hydraulic pump.

[Conventional technology]

Conventionally, the operating section of the power transmission described above is provided with a detector that detects a transmission state and a non-transmission state by the speed change operation valve in order to prevent a sudden start when starting the engine.
A starting device was provided that allowed the engine to be started only in the non-transmission state.

[Problem that the invention seeks to solve]

However, if the engine stalls while driving and you have to start quickly, for example to escape from a railroad crossing,
Even in a transmission state, the driver tends to reflexively start the engine, but it takes time to realize that the engine cannot be started unless the transmission control valve is in a non-transmission state. After noticing this, it is necessary to operate the speed change control valve from the transmission state to the non-transmission state and start the engine again, which requires much effort and time and may increase the danger.

SUMMARY OF THE INVENTION An object of the present invention is to prevent a sudden start when starting the engine, while also allowing a smooth starting operation when the engine is stalled.

[Means for solving problems]

The characteristic configuration of the operating section of the power transmission engine of the present invention is that an electromagnetic control valve is provided between the speed change operation valve and the hydraulic pump, and the control valve is controlled. a first detector for detecting a transmission state and a non-transmission state by the speed change operation valve; and a second detector for detecting an engine starting operation; Based on this, the control valve is brought into a pressure oil supply stop state by a starting operation of the engine in a transmission state, and by a starting operation of the engine in a non-transmission state, or a switching operation to a non-transmission state after starting the engine. The present invention is provided with a control device that puts the control valve into a pressure oil supply state, and its effects are as follows.

[For production]

In other words, even if it is not possible to start the engine only in the non-transmission state using the shift operation valve, if the engine is started in the pulp transmission state, the control device will stop the supply of pressure oil to the shift operation valve, so the engine will start. Power is not transmitted and the vehicle does not start. In addition, even if the engine does not start after starting, the driver can naturally switch the gear shift operation valve at the next stage without any resistance, and following the switching operation to the non-transmission state (sequence to the transmission state) With this operation, the control device smoothly supplies pressurized oil to the gear shift operation valve in a short time, transmitting engine power and allowing the vehicle to start moving.

〔Effect of the invention〕

Therefore, when starting the engine, you can reliably avoid a dangerous situation such as the engine starting unexpectedly and colliding with another object, and even if the engine stalls, you can easily escape from the dangerous situation without wasting time and be safe. We were able to improve performance and operability.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

As shown in FIG. 3, a front vehicle body (2) equipped with a pair of left and right front wheels (1) and a rear vehicle body (4) equipped with a pair of left and right rear wheels (3) are connected to the vertical axis ( The front body (2) is equipped with a front loader (5) that can be freely raised and lowered, and the rear body (4) is equipped with a riding section (6) and a driving section ( 7), and backhoe equipment (8)
), and a hydraulic cylinder (9) installed across both the front and rear car bodies (2) and (4) moves the front and rear car bodies (2) by an amount corresponding to the amount of operation of the steering handle (6a).
2) and (4) are configured to perform relative drive movement to direct the vehicle body, and a driving Mi7shigon case (11) is connected in conjunction with the engine (E) in the driving part (7).
The earthmoving vehicle is configured to transmit variable speed power from the front wheels (1) and rear wheels (3) to the front wheels (1) and the rear wheels (3), respectively, thereby carrying out work such as transporting earth and sand, etc. and excavation work.

As shown in FIGS. 1 and 4, the transmission structure in the traveling transmission case (11) includes an input shaft (12), a first intermediate shaft (13), and a second intermediate shaft. (14) are arranged concentrically, and the reverse cylinder shaft (15) is attached to the first intermediate shaft (13), and the output cylinder shaft (16) is relatively rotatable to the second intermediate shaft (14). Attach the disk-shaped members (17a) and (17b) to both ends of the spider (17).
) are respectively attached to the double cylinder shafts (15) and (16) so that they can rotate freely relative to each other, and the input shaft (12) and the first intermediate shaft (13)
A first multi-plate transmission clutch (18) is disposed between the input shaft (12) and the reverse cylinder shaft (15), and a second multi-disc transmission clutch (19) is disposed between the input shaft (12) and the reverse cylinder shaft (15). Third transmission clutches (20) are provided between the two intermediate shafts (14) and the output cylinder shaft (16), and the first transmission clutches (20) are separately attached to the first and second intermediate shafts (13) and (14). , the third and fourth gears (G3), (G4), which are always engaged with the second gears (G1) and (Gz), respectively.
．． ) is attached to the spider (17) so as to be relatively rotatable, and is engaged with the fifth and sixth gears (GS) and (G6), which are respectively attached to both cylinder shafts (15) and (16). 3. The 7th gear engages the 4th gear (G3) and (G O) separately.
, 8th gear (G?), (Gs) to spider (17
) to be relatively rotatable and to fix the reverse cylinder shaft (15) to the case (11).
), an internal gear (GF) that constantly engages the third gear (G1)
a multi-plate second brake (22) for fixing the second intermediate shaft (14) to the case (11); and a second intermediate shaft (14) to the case (11).
A multi-plate third brake (23) is provided for fixing the brake to the
Further, the input shaft (12) is connected to the engine (E) via a running latch (24) and a gear interlocking mechanism, and the output cylinder shaft (16) is connected to the front and rear wheels (1) via a gear interlocking mechanism. ) and (3) are interlocked and connected to the output shaft (25).

A hydraulic pump (P) is connected to a hydraulic cylinder section (188-23a) for clutch operation which is attached to each transmission clutch (18-23) in a state where it is always biased toward the transmission disengaged state.
A clutch operating inching valve (V
1), with 5 forward speeds (p+ ""ps),
2 reverse gears (R+, nz) and neutral gear a (N)
It is configured to be able to switch freely between the two, forming a power transmission as a whole.

Then, the speed change operation valve (V1) and the hydraulic pump (P
) is provided with a normally closed electromagnetic proportional valve (V1) that can freely adjust the hydraulic pressure of the oil supplied by a hydraulic pump (P),
A proportional valve controller (31) that controls the proportional valve (V2) is provided, a first detector (32) that detects the gear position by the gear shift operation pulp (V1), and an engine (
A second detector (35) for detecting the starting operation of the inching valve (V1) and a third detector (33) for detecting the transmission cutting operation for the inching valve (V1) are provided.
), (33), (35) is provided with a control device (34) consisting of a microcomputer which controls the proportional valve controller (31).

Then, as shown in the flowchart of FIG. 2, the control device (34) controls the first and second detectors (32), (
35), the proportional valve (VZ) is activated by starting the engine (E) in the transmission state at each gear.
The proportional valve (
The V-hole is opened and further controlled as follows. In other words, the first
Based on the information from the detector (32) and the third detector (33), when the inching valve (V1) is not operated, the transmission time at each gear of the speed change operation pulp (V1) is set to the set transmission time and is slowed down. The opening of the proportional valve (V*) is adjusted so that the modulation function for quick start is optimal for each gear, and when the inching valve (ν3) is operated, the transmission time is shortened regardless of the gear to provide a sudden start. The proportional valve (V2) is controlled to the preset large opening degree for starting operation.

Note that (D) in the figure is a drain tank.

[Bessio side]

The control device (34) and the operation section provided with an inching valve can be used not only for earthmoving vehicles but also for any working vehicle.

In addition to the relief valve, the inching valve (V1) for clutch operation, which is linked to the depression operation of the inching pedal (30), is connected to the drain tank without supplying pressure oil from the hydraulic pump (P) to the speed change operation pulp (Vl). It may be a switching valve that switches the supply to (D), or it may be another valve.

In order to perform control at the time of starting the engine (E), a simple on-off valve may be used instead of the proportional valve (V2), and these are collectively referred to as control valves. It may also be possible to detect only the non-transmission state.

[Brief explanation of the drawing]

The drawings show an embodiment of the operating section of the power transmission according to the present invention, in which Fig. 1 is a hydraulic circuit diagram, Fig. 2 is a flowchart, Fig. 3 is a side view of the earthmoving vehicle, and Fig. 4 is a schematic diagram of the speed change operating device. It is a diagram. (31)... Valve controller, (32)...
...first detector, (34) ...control device, (
35)...Second detector, (E)...Engine, (P)...Hydraulic pump, (V1)...
... Speed change operation pulp, (Vz) ... Control valve.

Claims (1)

[Claims] Shift operation valve (V) for power transmission
_1) is connected to a hydraulic pump (P), and is an operating section of a power transmission, which is connected to a hydraulic pump (P),
_1) and the hydraulic pump (P), the hydraulic pump (
An electromagnetic control valve (V_
2), a valve controller (31) for controlling the control valve (V_2), and a first detector (32) for detecting a transmission state and a non-transmission state by the speed change operation valve (V_1); , a second detector (35) for detecting a starting operation of the engine (E) is provided, and based on information from both the detectors (32) and (35), starting of the engine (E) in a transmission state is provided. The control valve (V_2) is operated to stop the supply of pressure oil, and the engine (E) is started in a non-transmission state, or the engine (E) is started and then switched to a non-transmission state. An operating section of a power transmission equipped with a control device (34) that puts a control valve (V_2) into a pressure oil supply state.