JPH0319430B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an actuator device, and more particularly to an actuator device in which an actuator is connected to an electromagnetic valve, and the fluid supplied to the actuator is controlled by the electromagnetic valve.

Automobiles are equipped with a transmission that changes the speed of the engine's rotation and transmits it to the drive wheels. When performing this speed change operation, the gear to which transmission is to be performed is selected by operating a shift lever provided at the driver's seat. In the gear shifting operation of this transmission, the shifter sleeve is moved and synchronized by a synchronizer ring, after which the shifter sleeve is brought into mesh with the gearshift gear of the main shaft. Therefore, when operating the shift lever by hand, resistance is felt midway through, and at this time, the movement speed of the shifter sleeve is slowed down to perform a synchronizing action.

In order to automatically change the speed of the transmission, an actuator such as an air cylinder is used, and this actuator moves the shifter sleeve via the fork. In order to perform this speed change operation, for example, a solenoid valve is opened to supply compressed air to the air actuator, thereby causing the piston rod to move forward.

However, when using a conventional solenoid valve, this solenoid valve only takes two modes: fully open and closed, so when the shifter sleeve is moved via the fork by the actuator, the amount of time per unit time is reduced. The stroke becomes constant. Therefore, using a solenoid valve with a small orifice that allows a slow speed for synchronization has the disadvantage that the operation is slow even when not synchronizing, and therefore it takes a long time to switch. .

Therefore, it is also considered to use an electromagnetic valve in which the diameter of the orifice changes so that the stroke of the actuator per unit time changes in stages. However, such conventional electromagnetic valves have a mechanism that mechanically changes the area of the orifice, and therefore have the drawbacks of complex structures and problems in terms of durability.

The present invention was made in view of these problems, and the amount of throttle of the electromagnetic valve changes from the position where the actuator stroke exceeds a predetermined value, thereby reducing the actuator's per unit time. It is an object of the present invention to provide an actuator device whose stroke changes in stages.

The present invention will be explained below with reference to an illustrated embodiment.
As shown in Figure 1, the electromagnetic valve has a casing 10
An inlet port 11 is formed on the upper surface of the casing 10.
An outlet port 12 is provided on the side surface of 0. Furthermore, within this casing 10, a partition wall 1 is provided.
A solenoid coil 14 is arranged below 3. A guide cylinder 15 is installed inside the solenoid coil 14.
is attached, and a plunger 16 is arranged so as to be slidable by this guide tube 15. The upper surface of this plunger 16 constitutes a valve, and is adapted to come into contact with a valve seat constituted by a ring-shaped projection 17 formed inside the inlet port 11.

The plunger 16 has a diameter smaller at its lower end than at its upper end, and a return spring 19 is interposed below the stepped portion 18 where the diameter changes. Further, above the stepped portion 18 of the plunger 16, a groove 20 for exhausting air is formed on the outer circumferential surface of the plunger 16 and extends in the axial direction. The return spring 19 passes through an opening 22 in the plate 21 and is received by the upper surface of a stopper 24 located in the lower casing 23. The stopper 24 is movably supported by a support portion 25 formed on the casing 23, and is pushed downward by a return spring 26 attached to the underside of the support portion 25.

An air passage 27 is formed in the stopper 24 so as to pass through the center thereof. And in order to exhaust the air passing through this air passage 27,
An exhaust port 28 is formed in the casing 23. Furthermore, a diaphragm 29 is attached to the casing 23 so as to divide the interior space into two, and this diaphragm 29 is connected to the stopper 24 by a screw 30. An inlet port 31 is formed on the lower side of the casing 23, and the diaphragm 29 is pushed by supplying control pressure through this port 31.

Next, the air actuator 32 controlled by the electromagnetic valve will be described. This actuator 32 is composed of a cylindrical body, and a piston 33 is slidably disposed inside the cylinder. . This piston 33 is the piston rod 3
4, and a fork 35 is fixed to the tip of this piston rod 34. This fork 35 is engaged with a groove formed in the outer circumferential surface of the shifter sleeve to move the shifter sleeve of the transmission in the axial direction. Further, the air actuator 32 has an inlet port 36 formed on its back side, and this port 36 is connected to the outlet port 12 of the electromagnetic valve via a conduit 37. Furthermore, a control port 38 is formed on the outer circumference of the air actuator 32 at a predetermined position in the length direction.
8 is connected via a conduit 39 to the inlet port 31 of the electromagnetic valve.

Next, a description will be given of the operation when changing the speed of a transmission using the device consisting of the electromagnetic valve and actuator 32 having the above configuration. When the shift lever provided at the driver's seat is operated, a switch (not shown) is closed, and the solenoid coil 14 of the electromagnetic valve shown in FIG. 1 is energized. Then, the coil 14 causes the plunger 16 to move downward against the return spring 19 as shown in FIG. 1, and stops at the position where it comes into contact with the stopper 24.

The upper end of this plunger 16 is therefore separated from the valve seat 17 of the inlet port 11, and this valve is opened. At the same time, the lower surface of the plunger 16 closes the air passage 27 of the stopper 24. Therefore, compressed air in an air tank (not shown) enters the casing 10 through the inlet port 11 and is discharged from the outlet port 12. This compressed air then passes through the pipe line 37 and enters the air cylinder 3.
The air is supplied into this cylinder 32 from the inlet port No. 2.

When compressed air is supplied into the air cylinder 32 from the port 36, the piston 33 moves to the right in FIG. 1 against the return spring 40, and the piston rod 34 is pushed out of the cylinder 32. Therefore, the fork 35 fixed to the tip of the piston rod 34 moves the shifter sleeve of the transmission.
The direction of this movement is the direction in which the shifter sleeve meshes with the selected transmission gear.

When the shifter sleeve is moved by the air cylinder 32, its teeth 41 move to a position in close proximity to the teeth 42 of the synchronizer ring, as shown by the chain lines in FIG. In this way, when the teeth 41 of the shifter sleeve move to a position where they are close to the teeth 42 of the synchronizer ring, the piston 33 of the air cylinder 32 is in the state shown in FIG. 38 will be held. Therefore, the back pressure in the air cylinder 32 is transferred to the inlet port 31 of the solenoid valve via the line 39.
The diaphragm 29 is pushed by the back pressure of the air cylinder 32.

As shown by the chain line in FIG. 1, when the diaphragm 29 is pushed upward, the diaphragm 2
The stopper 24 connected to the stopper 9 is also moved upwardly against the return spring 26, as indicated by the chain line in FIG. The stopper 24 is stopped at a position where the upper surface of the stopper 24 comes into contact with the plate 21. As the stopper 24 moves upward, the plunger 16 also moves upward, resulting in the state shown by the chain line in FIG. Therefore, the gap between the upper end of the plunger 16 and the valve seat 17 becomes very small.

When the piston rod 34 of the air cylinder 32 is pushed out to a predetermined position in this way, a restriction is formed at the inlet port 11 of the solenoid valve, which increases the air resistance and increases the air resistance per unit time. The amount of air supplied per unit decreases. Therefore, from then on, the stroke of the piston rod 32 per unit time becomes smaller. This situation is illustrated in the graph of FIG. As is clear from this graph, before control pressure is applied to the solenoid valve, the stroke per unit time is large, but when control pressure is applied to the solenoid valve, the stroke per unit time is small. Become.

Therefore, just before synchronization of the transmission starts, the air cylinder 32 slowly moves the teeth 41 of the shifter sleeve.
This gives the transmission time to synchronize.
Therefore, by using such an actuator device, the teeth 41 of the shifter sleeve of the transmission can be smoothly connected to the teeth 4 of the synchronizer ring.
2, and the synchromesh can operate smoothly and reliably. Furthermore, the time required for operation can be shortened compared to the case of using an electromagnetic valve with a small aperture as shown by the dotted line in FIG.

If the transmission is then to be transmitted using another gear, the teeth 41 of the shifter sleeve must be disengaged from the teeth 42 of the synchronizer ring. In this operation, the solenoid coil 14 of the electromagnetic valve is demagnetized as the shift lever is operated. Then, as shown in FIG.
Close 7. Therefore, in conjunction with this switching of the electromagnetic valve, the supply of compressed air to the air cylinder 32 is cut off.

Further, as the plunger 16 moves upward, the upper surface of the stopper 24 located at the chain line position in FIG. 3 is separated from the lower surface of the plunger 16, so that the air passage 27 is opened. The compressed air in the air cylinder 32 is thus supplied through its port 36 and the conduit 37 to the inlet port 12 of the solenoid valve. Furthermore, this air
It passes through a groove 20 formed on the outer peripheral surface of the plunger 16, and further connects the bottom surface of the plunger 16 with the stopper 2.
4, enters the casing 23 through the air passage 27 of the stopper 24, and is further discharged through the exhaust port 28.
Therefore, at this time, the piston 33 of the cylinder 32
is pushed by return spring 40, and piston rod 34 is moved to the left in FIG.

At the initial stage of the return movement of the air cylinder 32, the control port 38 is opened, and the air cylinder 3
The back pressure of 2 is pushing against the diaphragm 29 of the solenoid valve. Therefore, at this time, the stopper 24 is in the third position.
It is located at the position indicated by the chain line in the figure, and the gap between the upper surface of this stopper 24 and the lower surface of the plunger 16 is extremely small. Therefore, at this stage, exhaust resistance is added by the electromagnetic valve, slowing down the exhaust speed. Therefore, the shifter sleeve moves relatively slowly until the teeth 41 of the shifter sleeve pass between the teeth 42 of the synchronizer ring.

On the other hand, the piston 33 of the air cylinder 32
When the diaphragm 29 moves to a position where it closes or exceeds the control port 38, no pressure is applied to the diaphragm 29, so the stopper 24 is moved by the return spring 26 as shown by the solid line in FIG.
It will move downward. This increases the width of the gap between the upper surface of the stopper 24 and the lower surface of the plunger 16, reducing exhaust resistance. For this reason, exhaustion will be carried out rapidly from then on,
Correspondingly, the piston rod 34 of the air cylinder 32 also moves quickly, allowing the transmission to quickly change gears.

Such a backward motion of the air cylinder 32 is clear from the graph in FIG.
From then on, the stroke per unit time increases rapidly. Note that the characteristics shown by the dotted line in the figure are those when an electromagnetic valve having a fixed throttle is used.

As described above, by using the actuator device of this embodiment, the stroke per unit time is reduced only when necessary, and a reliable gear shifting operation is performed, so that the total time required for a gear shifting operation is reduced. In addition to making it possible to shorten the length of time, it is also possible to operate the synchronized mesh more smoothly. Furthermore, according to this embodiment,
A mechanical mechanism for changing the diameter of the orifice of the electromagnetic valve is no longer required, making it possible to provide an actuator device that is also favorable in terms of durability.

Although the present invention has been described above with reference to an illustrated embodiment,
The present invention is not limited to the above embodiments, and various modifications can be made based on the technical idea of the present invention. For example, although the above embodiment relates to an actuator device applied to a transmission, the present invention is applicable to various other devices. Further, the structure of the electromagnetic valve in the above embodiment can be modified in various ways.

As described above, the present invention provides a stopper that variably controls the stroke of the plunger by moving toward and away from the end surface of the plunger constituting the valve, with the end surface facing the valve seat, so that the stroke of the actuator reaches a predetermined value. When the stroke of the actuator exceeds a predetermined value, the back pressure of the actuator is supplied as control pressure to the moving means of the stopper, thereby changing the opening degree of the valve when the stroke of the actuator exceeds a predetermined value. be. Therefore, according to the present invention, it is possible to change the stroke per unit time of the actuator at any position. Moreover, since the diameter of the orifice is not changed mechanically, it is possible to provide an actuator device that is preferable in terms of durability. Furthermore, when the stroke of the actuator exceeds a predetermined value, the back pressure of the actuator is supplied as control pressure to the moving means of the stopper to change the stroke of the plunger and the opening degree of the valve. Also, there is no need to provide the electromagnetic valve with any movable parts other than the stopper, and the configuration is simplified.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing an actuator device according to an embodiment of the present invention, Fig. 2 is an exploded cross-sectional view of the main part of a transmission switched by this actuator device, and Fig. 3 is a double-movement operation of the actuator. 1, and FIGS. 4 and 5 are graphs showing the characteristics of the actuator during forward movement and backward movement, respectively. In addition, in the symbols used in the drawings, 14... Solenoid coil, 16... Plunger (valve),
24...stopper, 29...diaphragm, 32
. . . Air actuator, 38 . . . Control port.

Claims (1)

[Claims] 1. In a device equipped with an actuator and an electromagnetic valve that controls fluid supplied to the actuator, the valve is constructed by arranging a valve seat to face an end face of a plunger that slides by excitation and demagnetization of a solenoid coil, A stopper facing the end face of the plunger is provided, and moving means is provided for moving the stopper toward and away from the end face of the plunger in response to control pressure introduced from the outside, and when the stroke of the actuator exceeds a predetermined value. The present invention is characterized in that means is provided for supplying the back pressure of the actuator to the moving means as a control pressure, and the opening degree of the valve is changed as the stroke of the plunger changes due to the movement of the stopper. Actuator device.