JPH0636355Y2 - Hydraulic shift valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention provides a valve box with a pump port and an output / return port for a plurality of actuators having different capacities, a slide spool with a drain hole, and the output / return port. A communication passage for communicating a part of the return port with the pump port and a return passage for communicating the remaining part of the output / return port with the drain hole are provided in the spool, and the output / return port communicates with the pump port, The present invention relates to a hydraulic shift operation valve in which the communication passage and the return flow path are arranged so that a speed can be changed by a combination change based on a switching operation of the spool with an output / return port communicating with a drain hole. .

[Conventional technology]

Conventionally, in the above hydraulic shift operation valve, based on the spool switching operation, the return flow from the output / return port communicating with the drain hole is made so that the oil rapidly flows into the drain hole regardless of each shift stage. The road was formed.

[Problems to be solved by the invention]

However, depending on the gear stage, for example, when the actuator flowing from the pump port through the output / return port has a large capacity, as shown in FIG. Actuator (B ₁ ),
Since (B ₂ ) and (B ₃ ) are rapidly drained, the hydraulic pressure drops sharply, but as shown in Fig. 4 (b), the actuators (C ₂ ) and (C ₃ ) to takes time oil is filled, the actuator _{(C 2), (C 3} ) starting time of oil pressure starts to rise (T ₂₎ is significantly delayed, and not transmitted with the driving force time (T ₂ -T ₁ ) became longer, and there was a risk that the aircraft would retreat for a while at the same time as shifting gears.

An object of the present invention is to shorten or eliminate the time during which the driving force is not transmitted, which occurs with gear shifting.

[Means for solving problems]

The characteristic feature of the hydraulic shift valve of the present invention is that the throttle member can be freely inserted into and removed from the return flow path of the slide spool for the actuator having a smaller capacity of the plurality of actuators having different capacities. It is in the point of being fitted, and the operation and effect thereof are as follows.

[Action]

In other words, by fitting the throttle member in the return passage for the actuator with a small capacity, the return flow velocity of the oil flowing from the output / return port to the drain hole becomes slower. However, even if there is a
As shown in the figure (b), the actuator of the current gear
The starting time (T ' ₂ ) at which the hydraulic pressure of (C ₂ ) and (C ₃ ) begins to rise is significantly delayed, but as shown in Fig. 3 (a), the actuator (B ₁ ), (B ₂ ) and (B ₃ ) maintain the driving state for a while because the pressure of the loose oil decreases, and the time (T ′ ₂ −T ′ ₁ ) during which the driving force is not transmitted is shortened or eliminated.

[Effect of device]

Therefore, by simply modifying the spool so that the throttle member can be fitted appropriately, the start timing during gear shifting can be adjusted well, and even if gear shifting is performed on a slope, there is no trouble such as unexpected backward movement, and smooth operation is possible. It became possible to perform variable speed running.

〔Example〕

 Next, an embodiment of the present invention will be described with reference to the drawings.

As shown in FIGS. 1 and 2, the pump port (5) communicating with the hydraulic pump (P), the first actuator (B ₁ ), the second actuator (B ₂ ), the third actuator ( B ₃ ), 4th actuator (C ₂ ), 5th actuator
A valve box (4) having an output / return port (A) communicating with (C ₃ ) is provided, a drain hole (D) is formed in the shaft core, and an output / return port ( A) ・ ・ ・ ・ Communication passage (1) that connects a part of it to the pump port (5) ・
Slide spools (3) each formed with a return passage (2), ..., which connects the remaining portion of the output / return port (A) ... to the drain hole (D) in the radial direction. Is provided, and the slide spool (3) is slidable with respect to the valve box (4) in the axial direction of the slide spool valve.

With respect to the spool (3), the communication passage (1)
In the first gear (Fig. 2), the second actuator (B ₂ ) and the third actuator (B ₃ ) are connected to the hydraulic pump (P),
At the second speed (FIG. 1), the fourth actuator (C ₂ ) and the fifth actuator (C ₃ ) are arranged to communicate with the hydraulic pump (P), and the return flow passages (2) ... In the first gear (FIG. 2), the first actuator (B ₁ ), the fourth actuator (C ₂ ), and the fifth actuator (C ₃ ) are respectively connected to the drain hole (D), and in the second gear ( (FIG. 1) The first actuator (B ₁ ), the second actuator (B ₂ ), and the third actuator (B ₃ ) are arranged so as to communicate with the drain hole (D), respectively.

And the fourth actuator (C ₂ ) and the fifth actuator
Since the capacity with (C ₃ ) is larger than the other actuators (B ₁ ), (B ₂ ), (B ₃ ), the return flow path (2) in the second gear (Fig. 1) In addition, the orifice (6) ... Is screwed in and out so that the return flow from the first actuator (B ₁ ), the second actuator (B ₂ ), and the third actuator (B ₃ ) is narrowed. It is made to drain.

[Another embodiment]

Instead of the orifice (6) ..., the return flow path (2) ...
Any material may be used as long as it reduces the oil return speed in 1. and they are collectively referred to as a throttle member.

[Brief description of drawings]

The drawings show an embodiment of a hydraulic gear shift operation valve according to the present invention. FIGS. 1 and 2 are sectional views showing a shift switching state of a spool valve, and FIGS. 3 (a) and 3 (b) are The hydraulic pressure change graph of each actuator, and FIGS. 4 (a) and 4 (b) are hydraulic pressure change graphs of each actuator showing a conventional example. (1) …… Communication passage, (2) …… Return passage, (3) …… Spool, (4) …… Valve box, (5) …… Pump port,
(6) …… Throttle member, (A) …… Output and return port,
(D) …… Drain hole, (B ₁ ), (B ₂ ), (B ₃ ) …… small capacity actuator, (C ₁ ), (C ₂ ) …… large capacity actuator.

Claims (1)

[Scope of utility model registration request] 1. A valve box (4) having a pump port (5) ... and a plurality of actuators (B ₁ ), (B ₂ ), (B ₃ ), which have different capacities.
Output / return ports (A) for (C ₁ ), (C ₂ ) are provided, a drain hole (D) is provided in the slide spool (3), and the output / return ports (A) are provided. ..Communication path (1) that connects a part of .. to the pump port (5) ..
And a return flow path (2) for communicating the rest of the output / return port (A) ... With the drain hole (D) is provided in the spool (3) and communicated with the pump port (5). The output / return port (A) that operates and the output / return port (A) that communicates with the drain hole (D) are changed by a combination change based on the switching operation of the spool (3) so that the speed is changed. The communication passage (1) and the return flow passage (2)
Of the return flow path (2) ... Of the slide spool (3).
The plurality of actuators (B _1), for _{(B 2), (B 3} ), (C 1), a small actuator volume of _{(C 2) (B 1)} , (B 2), (B 3) A hydraulic speed change operation valve in which a throttle member (6) is removably fitted in the return flow passage (2).