JPS6118286Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a three-way control valve used in a control circuit for supplying vacuum to a vacuum actuator or the like.

A manifold vacuum is used to control a door that switches the flow of conditioned air in an automotive air conditioner. Conventionally, as shown in Fig. 1, a retaining ring 6 is fixed to the center of the bottom 5 of the case and the entrance of the case in a case 4 having three negative pressure passages 1, 2, and 3 on one side. A rod 8 is supported in a reciprocating manner in the center of the guide 7, and collars 9 are interposed in the middle of the rod 8, and four gaskets 10, 10, 10, 1 are attached at regular intervals.
0 are fixed with E-rings 11, 11, 11, respectively, and the inside of this case is connected to the first chamber 12, second chamber 13,
A spool valve 16 is formed by springing a spring 15 between the E-ring 11 located at the bottom of the rod 8 and the bottom 5. Therefore, when no external force is applied to the rod 8, the spool valve moves to the left in FIG. , the second and third passages 2 and 3 communicate with each other through a third chamber 14. Next, when an external force F is applied to the tip of the rod 3, the spool valve 16 moves to the right in FIG. 12, the second passage 2 corresponds to the second chamber 13, and the third passage 3 corresponds to the third chamber 14, and the first, second, third passages 1, 2, 3
are respectively blocked. However, it had the following drawbacks. The state in which the conduction of each negative pressure passage is switched is the travel distance of the valve part, and it is inevitable that the
3 mm, that is, the length of the seal for sealing, was required, and the product became larger accordingly. Since the gasket itself is made of a low-strength material such as rubber, it may break when passing through the negative pressure passage opening, resulting in poor durability.

Furthermore, as shown in Figs. 2 and 3, to explain the poppet valve, the first and second passages 2 are arranged on the same straight line.
1 and 22 and a third passage 23 on one side, a valve 25 is accommodated in a vertically movable manner, and a spring 26 closes the upper first passage 21 (the third passage 23 is located on one side). The first passage 21 is on the atmosphere side), and the operating rod 25a attached to this valve 25 is made to protrude outside the first passage 21. Therefore, when no external force is applied, the first passage 21 is in the state shown in FIG.
is closed by a valve 25, and the second passage 22 and third passage 23 are electrically connected. Next, an external force F is applied against the spring 26, and when the case is located in the middle, the first, second, and third passages 21, 22, and 23 are all electrically connected (FIG. 3). When the external force is further strong, the second passage 22 is closed by the valve 25 against the force of the spring 26, and the first and third passages 21 and 23 are communicated with each other. In this way, each passage can be switched. However, this poppet valve has the following drawbacks.
That is, each negative pressure passage becomes open when switching the conduction of each negative pressure passage. This is shown in FIG. 3 when the second passage 22 communicates with a negative pressure source, the first passage 21 communicates with the atmosphere, and the third passage 23 is set to negative pressure or to the atmosphere. Like, valve 25
When is in a neutral position, the negative pressure on the second passage 22 side ends up escaping from the first passage 21 to the atmosphere without doing any work. This was a large loss and uneconomical for vacuum pumps that generate negative pressure. Furthermore, when it is desired to increase the ventilation flow rate, the distance that the valve opens naturally increases, which inevitably increases the distance that the valve moves, resulting in a drawback that the state before switching becomes longer.

In view of these conventional drawbacks, the present invention prevents wastage of pressure gas and enables smooth switching when switching the pressure gas circuit. By opening and closing the second valve seat provided on the piston body and the first valve seat provided at the bottom of the storage chamber in the housing using a valve body housed so as to be movable up and down in the same direction as the force. , the first passage communicating with one of the second valve seat parts, the second passage communicating with the other part, and the third passage communicating with the first valve seat part are switched. Therefore, since the valve portion only repeatedly contacts and non-contact with the first and second valve seat portions, wear of the valve portion is reduced and durability is further improved.

An embodiment of the present invention will be described with reference to the drawings. A housing 31 that is open at the top and has a storage chamber 32 therein has a horizontal first passage 33 on one side of the substantially upper part, and a horizontal first passage 33 on the lower part of the other side. 2 passages 34 are formed, and a third passage 35 is formed in the vertical direction coaxially with a piston body 45, which will be described later, at the center of the bottom of the housing. At the upper end of this third passage 35, that is, at the center of the bottom part 30 of the storage chamber, there is a cylindrical first valve seat part 36.
is formed and protrudes into the storage chamber 2. A sealing chamber 37 with a slightly smaller diameter is provided at the lower part of the accommodation chamber 32 provided in this housing, and further a small diameter chamber 38 with a slightly smaller diameter is formed. An annular seal 40 is housed in this seal chamber 37, and a ring 41 for holding the seal is housed therein, and a locking groove 42 is formed inside the upper part of this ring. Reference numeral 43 designates a cylindrical cover body accommodated in the accommodation chamber 32, which presses the ring 41 at the lower end of the cover body 43 and
The upper part of 3 is connected to the storage chamber 32 by a stop ring 44.
It is stuck inside. A small diameter guide hole 39 is provided in the center of the upper part of the cover body 43. A piston body 45 is housed in a cover body 43 fixed to the housing so as to be movable up and down, and includes a locking collar 46 provided on the outer periphery of the upper part and a locking groove 4 provided in the stop ring.
A first spring 47 is urged between the piston body 2 and the piston body 45, and a push rod 48 fixed to the upper part of the piston body 45 is made to protrude outward from the guide hole 39. Reference numeral 50 denotes a working chamber provided inside the piston body 45 from the lower end side, the lower end of which is open, and the lower inner surface of this working chamber is annularly projected to form the second valve seat portion 51 . 52 is a valve body housed in the working chamber 50 so as to be movable up and down, and is constantly urged downward by a second spring 53, which is weaker than the first spring 47, and is located at the lower end of the valve body.
A valve part 54 is attached to the lower part of the valve body, and is seated simultaneously or alternately with the first valve seat part 36 and the second valve seat part 51. This valve part 54 is made of an elastic material such as rubber, and when it engages with the first and second valve seats 36 and 51, the moving distance of the valve part is changed by the amount of compression of the valve part made of the elastic material. It is possible to reduce the thickness to about 0.1 mm. Furthermore, a through hole 55 is formed in the side surface of the piston body 45 to allow communication between the first passage 33 and the inside of the working chamber 50 . Further, in order to improve the flow of gas between the valve body 52 and the inner wall of the working chamber 50, in addition to the gap 56 between the two, a groove 57 may be provided on the side surface of the valve body 52 and the valve portion 54. . Moreover, the piston body 45 is located at the bottom 30
A recess 30a is provided at the bottom or the lower end of the piston body so that the second valve seat portion 51 and the second through hole 34 can communicate with each other even when the piston body comes into contact with the piston body.

Next, to explain the operation, as shown in FIG. 4, when no external force is applied to the piston body 45, the piston body 45 is pushed upward by the elastic force of the first spring 47, and the cover body 43
Since the second valve seat part 51, which is engaged with the piston body and provided inside the lower part of the piston body, is located above the first valve seat part 36, it is held downward by the second spring 53 in the working chamber 50. The valve part 5 attached to the valve body 52 which is being energized
4 leaves the first valve seat part 36, but seats on the second valve seat part 51 and enters the valve closed state. In this case, since the space between the piston body 45 and the accommodation chamber 32 of the housing is sealed with a sealing material 49, the first passage 3
3 is shut off and closed by the second valve seat portion 51, and the second valve is closed.
The passage 34 and the third passage 35 are in communication.

Next, as shown in FIG. 5, when a force F is applied to the piston body 45 from the outside, the piston body 45 descends while compressing the first spring 47, so that the valve portion 54 is seated on the second valve seat portion 51. It descends while holding the position, and further seats on the first valve seat portion 36. That is, the first,
The second and third passages 33, 34, and 35 can all be closed.

As shown in FIG. 6, when an external force F is further applied, the piston body 45 compresses the first spring 47 and descends until it comes into contact with the bottom 30 of the storage chamber 32, but the valve part 54 Since the valve element 52 with the valve part 54 remains in this position while compressing the second spring 53, as it cannot descend any further after being seated on the first valve seat part 36, as a result, the second valve seat part 51 is opened away from the valve part 54, and the first passage 33 and the second passage are opened.
The passage 34 is in communication, and only the third passage 35 is closed.

As described above, in the present invention, all the passages are closed when the passages are switched, so it is possible to prevent the waste of negative pressure or pressure gas, and furthermore, when the conduction is switched, the valve part is moved. The distance may be extremely short, equivalent to the amount of material constituting the valve part being crushed, so the switching operation distance is shortened, and other functional parts linked to the control valve of the present invention can also be operated by a small amount. As a result, the system can be further miniaturized. Furthermore, the valve part does not switch conduction by sliding, but by repeatedly making contact and non-contact with the first and second valve seats, so wear on the valve part is reduced.
Durability can be further improved.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a conventional spool valve, Figs. 2 and 3 are sectional views of the conventional spool valve, and Fig. 4 shows an embodiment of the present invention.
A cross-sectional view of the state in which three passages are connected, Figure 5 is the first,
A cross-sectional view of the 2nd and 3rd passages closed, Figure 6 is the 1st
It is a sectional view of a state where a passage and a second passage are connected, and a third passage is closed. 31 is a housing, 33, 34, 35 are passages,
36 is a first valve seat, 45 is a piston body, 47 is a first spring, 51 is a second valve seat, 52 is a valve body, 53 is a second spring, and 54 is a valve part.

Claims (1)

[Scope of utility model registration request] A piston body having a first passage on one side of the upper part and a second passage on the other side of the lower part is housed in a housing so as to be movable up and down, the piston body having an upper end projected outside the housing by a spring. A second valve seat is formed in the lower part of the working chamber provided in the piston body, and the valve body, which is urged downward by a spring inside the piston body, is seated on the second valve seat, and the movement direction of the piston body is A third portion located on the same axis as the housing and provided at the bottom of the housing.
A three-way control valve, in which a first valve seat part that seats on the valve body is provided at the upper part of the passage, and the first and second valve seat parts can be closed simultaneously by the valve body.