JPS60146971A - Changeover valve - Google Patents

Abstract

PURPOSE:To reduce leakage of fluid by moving a valve through piston containing said valve and flowing/blocking fluid against each port. CONSTITUTION:Pistons 11, 12 are provided on a piston rod 10 arranged in the inner hole 2 of changeover valve where a valve 20 is contained in the center of shaft section 15. A recess 22 is formed in the valve 20 at the side contacting with the inner hole 2 to provide a land 21. Upon location of piston rod 10 to the right end, fluid is blocked between the ports 5, 6 and port 4 through the land 21 while the ports 6, 5 are communicated through the recess 22. Even when the diameter of arched cross-section of land 21 is same with that of the inner hole 2, it can slide to eliminate leakage resulting in facilitation of work and reduction of leakage.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a simple gutter structure that is used between hydraulic and pneumatic switching valves, and there is a need for a switching valve that is less leaky, has a long life, and is highly durable.

In order to meet these demands, we have developed new ceramics,
Although it can be inferred that engineering plastics could be used effectively, it is not easy to find a specific structural configuration.

In particular, new ceramics are not easy to process, and engineering plastics are prone to deformation and dimensional changes due to changes in temperature and humidity over time. This necessitated the invention of a new structure.

The present invention can meet such demands.

The present invention will be explained with reference to the drawings.

In order to make the explanation easier to understand, the nine drawings will be explained using top and bottom, left and right, and front and back, but in actual implementation, the structural configuration will be
It goes without saying that it is good as long as it does not deviate from the essence of this invention.

FIG. 1 is a longitudinal sectional view of a typical example of a conventional hydraulic pneumatic switching valve.

Since the two generally well-known features of this configuration can be easily compared and contrasted, the example shown in FIG. 1 will be explained below.

31 is nine bodies, and an inner hole 32 having a circular cross section is provided to pass through the two bodies 31.

Boats 33, 34, 35, 36, and 37 are provided in the main body 31 at fixed intervals, as shown, intersecting the inner hole 32.

A spool 4o is attached to the inner hole 32 so as to be slidable left and right.

The spool 40 has a land 4 which fits into the inner hole 32 with a slight gap, and 42, 43, 44 are provided at the left and right ends and two places inside the land as shown in the figure, and the space between each land is thin. and the shaft portion 45, respectively.
In FIG. 1, the spool 40 is at the center point of operation, the runt 42 covers the boat 34, and the land 43 covers the boat 36.

When the spool 40 is at the left end, the shaft portion 46 is
It is located above boats 5 and 34, and boats 35 and 34 communicate with each other.

At this time, the shaft portion 47 is on the boats 36 and 37, and the boats 3B) 37 are in communication.

When the spool 40 is at the right end, the shaft portion 45 is above the boats 33 and 34, and the boats 33 and 34 are in communication. This sharpening shaft portion 46 is located above the boats 35 and 36, and the boats 35 and 36 communicate with each other.

A switching valve having such a configuration is generally called a spool type and is well known.

The spool 40 is provided at the left and right ends of the two main bodies 31 for left and right movement. This may be accomplished by applying two fluid pressures to the pressure introduction holes 50, 51 provided in each of the lids 48, 49, or by a quasi-magnet or other actuator.

Although such conventional spool-type switching valves have been in use for many years and exhibit stable functions, they have the following drawbacks.

To explain this drawback, the diameters of the lands 41, 42, 43, and 44 must be made very slightly smaller than the diameter of the inner hole 32. Extremely high precision is required.

As an example, if the diameter of the inner hole 32 is 16 mm and the air pressure is 5 KG/side, land 4 1
, 4.2. 43. 44 is 0. If you make it smaller by 004 millimeters (4 micrometers),
When air pressure is introduced into the boat 35 when the spool 40 is at the left end, the total amount of air leaking into the boats 33 and 37 is about 1 OONcc/Mi.

In the present invention, if the work is performed with the precision described above, the leakage will be approximately 1/20. However, the fluid passage capacity is also 1
/3, but when compared with the same fluid passing capacity, it decreases to l/3.
This will result in approximately 7.7% of the outstanding debt.

However, with conventional products, the more you use them, the more
Although the amount of leakage has increased, in the case of the present invention, the more the valve is used, the more the inner hole and the valve come into close contact with each other due to wear, and the amount of leakage decreases.

The present invention will be explained with reference to two drawings.

FIG. 2 is a longitudinal sectional view of a preferred embodiment of the present invention.

Reference numeral 1 denotes a main body, and an inner hole 2 having a circular cross section is provided through the main body r.

A piston rod 10 is provided in the inner hole 2 so as to be movable left and right.

Pistons 11 and 12 are formed on the left and right ends of the piston rod 10.

The pistons 11.12 are loose in the inner bore 2, and in order to prevent fluid leakage between the inner bore spaces on the left and right sides of each piston, gaskets 13.14 are provided on the outer periphery of the pistons 11.12, respectively, as shown in the figure. It is provided.

While the piston rod 10 is sandwiched between the pistons 11 and 12,
In the embodiment, it is made slightly thinner and forms a shaft portion 15.

Even though the shaft 91<15 has the same thickness as the piston 11.12, its function remains the same.

The center portion of the shaft portion 15 has a recess 16 for accommodating the valve 20.
is formed.

The relationship between the shape of the valve 20 and the overall structure is the main point of the present invention.

The cross section of the valve 20 does not touch the entire cross section of the inner hole 2 as shown in FIG.
81().

It is important that this contact be made so that the area is smaller than a semicircle.

In particular, the sliding movement of the pistons 11 and 12 and the valve 20
Considering the 1ξ resistance, it is preferable to set the circle to 1/3 or ]/4.

As shown in FIG. 4, the valve 20 is formed with a recess 22 on the side that contacts the inner hole 2, and a land 21 is formed around the recess 22 so that it can come into contact with the inner hole 2t. has been done.

In the main body 1, boats 4, 6.6 are arranged in the axial direction of the inner hole 2 at the center thereof as shown in the figure.
6.

Bo) 4,8. Arrangement of δ and lands 21, 1 of valve 20
The IAI staff at 111 and 22 is important for the function of this switching valve.

The bows 1"L+6+5 are arranged in order from the left.

In FIG. 2, the piston rod 10 is located at the right end, but at this time, the recess 22 of the valve 20 covers the boat 5.6, and the left side of the land 21 is located between the boats 11 and 6. Fluid communication between the boat 5.degree. 6 and the boat 4 is cut off by the runt 21, and the boats 6 and 5 are kept in a dimensional relationship such that they communicate through the recess 22.

When the piston rod 10 is located at the left end, the recess 22 is
Located above bow +-ll and 6, the right end of land 21 is
It is located between boats 5 and 6, and in this state, fluid communication between boat δ and boats 4 and 6 is cut off, and boats 4 and 6 are in communication.

A boat 3 is provided in the main body 1 so that fluid can be introduced between the pistons 11 and 12 no matter where the piston rod 10 is located on the left or right end.

In such a structural configuration, when fluid is supplied from the boat 3, when the piston lO and the valve 20 are in the positions shown in the right end 2, the boats 3 and 4 communicate with each other, and the boats δ and 6
are connected to each other.

When the piston 10 is located at the left end, the boats 3 and 5 and the boats 4 and 6 communicate with each other.

This connection relationship of Bo) 3, 4, 5.6 is,
This is what is called the i1 boat switching valve and has two functions.

With this configuration, even if the diameter of the arc of the cross section of the runt 21 of the valve 20 shown in FIG. 3 is manufactured to the same dimension as the diameter of the inner hole 2, sliding is possible. The collapse of the fluid is zero.

In addition, even if the inner hole is made somewhat larger or smaller than the inner hole 2, the fifth
As shown in the figure, the gap is half-moon-shaped, and the maximum gap
(60) is approximately 14% of the diameter difference when the circular angle A (63) is 90 degrees.

On the other hand, in the case of the one shown in FIG. 1, the gap is equal to 1/2 of the diameter difference as shown in FIG.
．． 44, the spool 40 can be slid left and right.

Also, the diameter of the lands 41, 42, 43, 44 is the same as that of the inner hole 32.
If the diameter is larger than that, it cannot be inserted into the inner hole 32.

On the other hand, the second invention according to the present invention can be used even if the diameter of the land 21 is slightly larger than the diameter of the inner hole 2, as shown in FIG.

FIG. 7 shows the state of contact when the diameter of the land 21 is smaller than the diameter of the inner hole 2.

In the case of FIG. 7, the contact part 25 crosses the bow) 4, 5.6 and collides with the edge, which seems to be a problem, but as shown in FIG. 8, the edge of the land 21 of the valve 20, boat 4,5
．． Chamfers 26, 27 or 8, 9 may be applied to the edges of 6.

In this way, the fact that the diameter of the inner hole 2 of the valve 20 may be the same or may be slightly larger or smaller makes manufacturing very easy.

Specifically, as a method of machining the diameter of the runt 21 with high precision, as shown in Figure 9, if several valves are tied together and two cylinders are polished, it is possible to machine the diameter of the runt 21 to extremely high precision dimensions. .

In FIG. 10, as an application of the present invention, the recesses of the valve 2o are provided as 23 and 24 as shown in the figure.9 The main body 1 is further provided with a boat 7 between the boats 6 and 5, as shown in the figure. When the valve 20 is at the right end, the recess 24 is located on the boats 5 and 7 and the boats 5 and 7 are in communication, and the boats 3 and 4 are in communication, when the boat 6 is closed and the valve 20 is in communication. When is at the left end, the recess 23 is located above the boats 4 and 6, the boats 4 and 6 are in communication, the boat 7 is intersected, and a dimensional relationship is established in which the boats 3 and 5 are in communication. Leave it alone.

This relationship between the passages of each boat is well known as the passage relationship of a five-boat valve.

FIG. 17 shows a spring for keeping the valve 20 in light contact with the inner hole 2 at all times.

When the two inventions are implemented in this way, the work is easy, there is little fluid leakage, and the leakage is reduced according to the usage time.In the case of the one shown in FIG. If it is bitten, the spool 40 will not move, but in the case of the present invention, the valve 20 wipes away the dirt along the inner hole 2.

Furthermore, even if dirt gets caught in the land 21 of the valve 20, the valve 20 can operate without any problem because it is only lightly pressed against the inner hole 2 by the spring 17.

Therefore, the reliability for two operations is also much higher than that in FIG.

Even if the valve 20 is made of a material such as plastic or ceramic, it will not be as good as that of the spool 40 shown in FIG.
The shape is not susceptible to bending due to aging or breakage due to impact, so plastic has the characteristic of smooth movement, while ceramic has the characteristic of extremely low wear.

In the case of plastic, the modulus of elasticity is lower than that of metal, so it adheres well to the inner hole 2 of the land 21. It also has good "fitting in" due to wear, making it easy to create a switching valve with less leakage.

In the case of ceramic, there is no occurrence of phenomena such as "sticking" against dust, etc., and the m-axis property is high.

Long-life switching valve can be replaced.

In order to move the piston rod 10 left and right, fluid is supplied from the pressure guide holes 73 and 74 provided in the lids 71 and 72 provided at the left and right ends of the inner hole 2 to the respective operating states, similar to the one in FIG. You can also apply pressure. The actuator may be an electromagnet and a spring, or may be any other actuator, and may be any conventional actuator.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a longitudinal sectional view of a typical example of a conventional switching valve. FIG. 2 is a longitudinal sectional view of a preferred embodiment of the present invention. FIG. 3 is a cross-sectional view of the one in FIG. 2. FIG. 4 is a drawing showing the valve 20. 5 and 7 show a second diagram explaining the gap between the valve 20 and the inner hole 2.
A partial cross-sectional view of the one shown in the figure. FIG. 6 is a partial cross-sectional view of FIG. 1 illustrating the relationship between the gap between the spool 40 and the inner hole 32. Figure 8 shows the edge of the land 21 and the boat 4,6° (7),
FIG. 9 is a partial vertical sectional view showing an embodiment of the edge of valve 2.
Drawing for explaining a preferable manufacturing method of 0. FIG. 10 is a vertical cross-sectional view of one embodiment of the present invention in which the present invention is made into a five-boat valve. 1 is the main body, 2 is the inner hole. 3.4,5,6,7. A boat. 8.9 is chamfered. 10 is the piston rod. 11.12 is the piston. 15 is the shaft part. 16 is a recess. 17 is a spring. 20 is a valve. 22, 23, and 24 are depressions. 26.27 is chamfered. 31 is the main body 4 32 is the inner hole. 33.34, 3δ, 36.37 are boats. 40 is the spool. 41.42, 43.44 are Rand. 45.46.47 is the shaft part. 48.49 is the lid. 50.51 is a pressure introduction hole. 60 is the maximum gap. 61.62 is a gap. 63 is the angle of the cut. 71.72 is the lid. 73 and 74 are pressure introduction holes. Patent applicant Todoroki 1 BeJ

Claims (2)

[Claims] (1) The main body 1 is provided with an inner hole 2 having a circular cross section. Bows 3, 4, 5° 6 are provided on the 9 body l to intersect with the inner hole 2, and a piston rod 10 is provided in the inner hole 2 so as to be movable left and right. The piston rod 10 has pistons 11.1 at its left and right ends, respectively.
2, and the central part is recessed so that a valve 20 can be attached thereto. The land 21 of the valve 20 is in contact with the inner hole 2 and is movable from side to side, and is in contact with a portion of the circular cross section of the inner hole 2 that is less than a semicircle, so that one of the boats 4, 5, and 6 can be moved along the shore. make it move. The surface of the valve 20 that slides into the inner hole 2 is a gate, and a runt 21 is formed around it. The boat 3 is located approximately in the center of the two main bodies 1, between the left and right pistons 11 and 12 of the piston rod 10. Do as you wish. The bows 4 and 6.5 are provided approximately in a line in the direction of the axis of the inner hole 2 at a constant interval at approximately the center of the two bodies 1. In the above structural configuration, when the valve 20 moves to the left end, the recess 22 of the valve 20 covers the boats 4 and 6, communicating the boats 4 and 6, and the boat 5 is separated from the valve seat 21.
When the boats 5 and 3 are in communication and the valve 20 is moved to the right end, the recess 22 of the valve 20 covers the boats 5 and 6, so that the boats 5 and 6 are communicated, and the boats 4 and 3 are in communication. Diverter valve configured as related dimensions. (2) When the boats 4, 6, 7.5 are provided in the main body 1 in a row in the direction of the axis of the inner hole 2, and the valve 20 is provided with two recesses 23, 24, and the valve 20 is at the left end, . The recess 23 covers the boats 4 and 6, the valve seat is separate from the boat 5, and the boat 5 communicates with the boat 3, and when the valve 20 is at the right end, the recess 24 covers the boats 5 and 7, and the valve seat is separated from the boat 5 and communicates with the boat 3. 7
2. The switching valve according to claim 1, wherein the switching valve is configured such that the boat 4 communicates with the boat 3.