JPH0532718Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial field of application) This invention relates to a manual drain valve that is attached to the air reservoir of a pneumatic device, such as a vehicle air brake. Therefore, the present invention relates to a technique for preventing valve seal failure.

(Prior Art) A drain valve is a valve for discharging drain accumulated at the bottom of an air reservoir or the like. Conventionally, two types of valves are known: a manual type in which drain is discharged manually, and an automatic type in which drain is discharged automatically. Here, we will focus on manual type drain valves and automatic type drain valves with a manual operation mechanism added, in short, manual drain valves that can be operated manually.

As this type of drain valve, for example,
The one described in Publication No. 35824 is known.
This drain valve is normally operated automatically by a control signal using compressed air issued from a governor or the like, but in addition, a manual operation mechanism that can be operated from the outside is also added. The manual operating mechanism offers the advantage of being able to drain the condensate at will. The manual operation mechanism includes a manual operation member such as a chain, and the operation member protrudes from an outlet that is a passage for drain. Therefore, the operator can discharge the drain in a timely manner by manually operating the operating member from the outside.

However, since the valve part of such drain valves is directly connected to the outside air, there is a problem that dirt and snow from the outside air can enter the valve part and get caught in the seal part, resulting in a seal failure. Ta.
This problem is particularly noticeable in vehicles such as automobiles that are used in harsh environments.

(Problem to be solved by the invention) As a method to solve such seal defects, it is possible to cover the entire drain valve with a cover by applying the idea disclosed in the publication of Utility Model Publication No. 57-2785. Conceivable. However, even if it is covered with a cover, the cover must have an opening for drainage, and there is still a risk that dirt and snow may enter the valve portion of the drain valve through this opening. Of course, it is possible to consider making the opening of the cover smaller, but there is a limit to how small the opening can be made in consideration of drainage. Particularly in a manual drain valve in which an operating member protrudes from the discharge port, the operating member becomes an obstruction, making it even more difficult to cover the outlet opening, which is the passage for drain, without any gaps.

Further, in the technique of providing a cover that covers the entire device, a large cover that is a separate member must be provided, and parts for attachment are also required, resulting in an increase in the number of parts. Furthermore, since it covers the entire drain valve, it requires a large installation space, so there is a problem that it can only be used when there is sufficient installation space, for example.

This invention was made taking the above points into consideration, and is a manual drain that can protect the seal part of the valve without impairing drainage, and has an advantageous structure in terms of installation, etc. The purpose is to provide a valve.

(Summary of the invention) In this invention, a check valve is provided in the drain path to cover the opening.

Since the check valve can cover the opening without any gaps, it prevents the intrusion of dirt and other substances and effectively prevents seal failures, while at the same time releasing the seal and ensuring smooth drainage when draining. Discharge outside. Furthermore, since the check valve only covers the opening, it can be a simple small member and requires little installation space.

(Embodiment) FIG. 1 is an example of application to a manual drain valve that can discharge drain only by manual operation.

The outer shell of the manually operated valve 10 is a cylindrical housing 12. The housing 12 has a threaded portion 12a at one end, and the male threaded portion 12a is screwed to the bottom portion on the air reservoir side. Further, the housing 12 has a stepped shape, and the outer diameter on the side of the male threaded portion 12a is the smallest, and from the opposite side, the male threaded portion 12a is the first step, the second portion 12b, the third portion 12c, and the outer diameter of the outer diameter is the smallest. The outer diameter of the four sections 12d is gradually increased over four stages. In accordance with this, the diameter of the center hole 14 that passes through the interior of the housing 12 from one end to the other is gradually increased. One end of the center hole 14 is an inlet 16 that communicates with the interior of the air reservoir, and the other end is an outlet 18 that communicates with the outside air. The inlet 16 includes a first passage 14a having a small diameter, and second, third, and fourth passages 14b and 14 having successively larger diameters.
It communicates with the outlet 18 through c and 14d.

The operating member 20 for manual operation is rod-shaped,
One upper end thereof fits into the center hole 14, and the other lower end projects outward from the outlet 18. There is a horizontal hole 20a in the protruding part. A member (not shown) for transmitting operating force, such as a link, ring, or chain, is attached to the side hole 20a. On the other hand, one upper end of the rod-shaped operating member 20 is
Passing through the third passage 14c, the second passage 14b
It has reached close to. The valve portion of the drain valve 10 is located near the third passage 14c. Operation member 2
A mounting groove 20b is provided around the upper end of the
A lip-type valve member 30 is mounted therein. The valve member 30 is also attached to the operating member 20 by a support ring 32 that supports the upper end, and a cup-shaped presser cap 34 that holds the support ring 32 and supports the peripheral side of the valve member 30. The support ring 32 also functions as a spring holder for a spring 36 that urges the operating member 20 downward.

The valve member 30, which is biased together with the operating member 20 by a spring 36, bears its lip 30a tightly against the upper surface 40a of the insert 40. The insert 40 is a ring that matches the diameter of the fourth passage 14d. This insert 40 fits into the fourth passage 14d while holding a seal ring 42 on its outer periphery and is supported by a stopper ring 44. The hole 46 in the inner periphery of the insert 40 is sufficiently large for the operating member 20 passing through it to ensure a drain passage around the rod-shaped operating member 20. Note that there is a taper 4 on the side of the hole 46 facing the opening 18.
6a, whose taper 46a allows the operating member 20 to move laterally during manual operation.

This manual drain valve 10 further includes a check valve 50 at the outlet 18, that is, at the opening. The check valve 50 is made of a ring-shaped rubber plate. The rubber plate is supported by fitting into a groove 20c provided in the operating member 20, and the upper surface of the outer peripheral portion lightly contacts the lower end of the fourth portion 12d of the housing 12 surrounding the outlet 18. Note that the taper of one side surface 20d of the groove 20c is intended to facilitate insertion and installation of the check valve 50, and also to facilitate draining during manual operation.

Now, the drain collected at the bottom of the air reservoir is
It enters the housing 12 through the inlet 16 and accumulates in the internal space sealed by the valve member 30. In this state, the check valve 50 is connected to the valve member 3.
It tightly covers the opening of the outlet 18 which communicates with the seal portion of the opening. Therefore, external dust, snow, etc. do not enter the inside of the housing 12.

On the other hand, in order to discharge the drain, the lower end of the operating member 20 is pushed or tilted laterally using a ring or the like attached to the side hole 20a. The operating member 20 then swings while deforming the spring 36, releasing the seal between the valve member 30 and the insert 40 at the upper end. As a result, the drain accumulated inside is pushed out from the gap in the inner circumference of the insert 40 to the opening side of the outlet 18 together with the compressed air in the air reservoir. At this time, the operating member 20
Along with the movement, the check valve 50 also moves laterally,
It tries to move away from the lower end surface of the housing 12. Since the drain accompanied by compressed air flows therein, the drain is smoothly discharged to the outside due to the synergistic effect of the elastic deformation of the check valve 50 and the above-described movement. Then, when the operation of the operating member 20 is stopped, the operating member 20 is moved back to its original state by the biasing force of the spring 36. Thereby, the lip 30 of the valve member 30
a again closely contacts the upper surface 40a of the insert 40, and the check valve 50 also returns to its original state so as to cover the opening of the outlet 18.

As mentioned above, the manual drain valve 10 shown in the figure
Since it covers the opening of the outlet 18 without a gap unless an operation is performed to discharge the drain, it is possible to reliably prevent foreign dirt, snow, etc. from entering the seal portion or valve portion inside the housing 12. .

In addition, in the example shown in the figure, since the check valve 50 is attached to the operating member 20 side, not only the check valve 50 itself can be attached easily, but also the responsiveness to the movement of the operating member 20 is good. Furthermore, the sealing performance with the housing 12 is also very good. However, this invention is not limited to that example, and the check valve 5
0 can also be attached to the housing 12 side.

Furthermore, since the manual drain valve 10 uses the housing 12 itself as a part of the cover, it is extremely simple to cover the opening of the outlet 18, and can be easily applied to conventional drain valves. Can be done.

(Effects of the invention) According to this invention, since the opening of the outlet 18 is covered with the check valve 50, the sealing part of the valve is protected and sealing failures caused by intruding dust are effectively prevented. and at the same time,
Drain can be discharged smoothly. Furthermore, since the structure covers the opening, the overall structure is simple and very advantageous in terms of space and number of parts.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of this invention. 10...Manual drain valve, 12...Housing,
16... Inlet, 18... Outlet, 20... Operating member, 50... Check valve.

Claims (1)

[Scope of utility model registration request] An inlet communicating with the inside of the pneumatic equipment, an outlet communicating with the outside air, a discharge valve provided in a passage between the inlet and the outlet, and an operating member protruding from the discharge valve to the outside through the outlet. In the manual drain valve, the outlet is provided with a check valve that covers the opening.