JPH034245B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a technique for securing a necessary amount of compressed air for regeneration in a compressed air drying device used in a pneumatic circuit such as an air brake device of a vehicle or the like.

Traditionally, this type of compressed air drying equipment
A dryer that dries compressed air from an air compressor using a recyclable desiccant; a purge reservoir that stores a portion of the compressed air from the dryer for regeneration and supplies the remainder to a main reservoir; a drain valve that connects the air compressor side to the outside air in response to an external signal; and a first drain valve that is provided between the inside of the dryer and the inside of the purge reservoir to prevent backflow to the desiccant side. a stop valve, a throttle passage that constantly communicates both sides of the first check valve, and a second check valve provided between the inside of the purge reservoir and the inside of the main reservoir to prevent backflow to the purge reservoir side. A stop valve is known (for example, U.S. Pat. No. 3,080,693,
(or Japanese Patent Application Laid-open No. 136575/1983).

By the way, in order to maintain a good drying function over a long period of time in such a drying device, it is necessary to appropriately regenerate the desiccant whose drying ability has decreased by capturing moisture. For this purpose, it is desirable to store a sufficient amount of compressed air for regeneration in the purge reservoir. However, although the dry compressed air in the purge reservoir is used for regeneration, it is wasteful from the perspective of brake systems that use compressed air as a driving source, and conventionally, the capacity of the purge reservoir has generally been set to the minimum necessary. There is. The capacity of this purge reservoir can be determined depending on the drying capacity of the desiccant and the amount of air passing therethrough.

However, on the other hand, desiccants with higher drying ability have appeared, and in order to fully utilize their drying ability, it has become necessary to increase the amount of compressed air for regeneration. This can be addressed by increasing the capacity of the purge reservoir, but in this case the drying equipment will become larger and
This may cause problems such as difficulty in attaching it.

This invention was made in consideration of the above points, and its purpose is to eliminate the need for compressed air for regeneration without making the purge reservoir excessively large even when a desiccant with high drying ability is used. The objective is to provide technology that can easily secure quantities.

Another object of the present invention is to provide a technique that can be easily and simply applied to conventional drying equipment.

Other objects and novel features of this invention include:
It will become clear from the description of this specification and the accompanying drawings.

In this invention, the opening pressure of the second check valve provided between the inside of the purge reservoir and the inside of the main reservoir is set to a predetermined value, for example, 0.5 to 0.5.
By setting the valve opening pressure to ^about 1.5Kg/cm2, the air pressure in the purge reservoir will be higher than that in the main reservoir by the amount of valve opening pressure, effectively increasing the amount of compressed air for regeneration. I'm in

Hereinafter, the content of the present invention will be made clear by describing embodiments shown in the accompanying drawings.

The drawing is an overall configuration diagram showing an embodiment of a compressed air drying apparatus to which the present invention is applied, including a piping system. In this figure, the feature of this invention is the second part surrounded by a broken line.
It is located in the check valve 200 part of. The configuration of other parts is the same as the conventional one. Therefore, we will first describe the parts that are the same as before, and then explain the distinctive parts.

The compressed air drying device 1 includes a dryer 3 that has a recyclable desiccant 2 therein and dries compressed air, and a drain valve 4 that controls communication between the inside of the dryer 3 and the atmosphere and discharges condensate. It is equipped with

The casing of the dryer 3 has an upper member 5 forming a lid.
and a lower member 6 having a sufficient storage space inside. Both the upper and lower members 5 and 6 are made of metal such as aluminum, and are fixed integrally and airtightly with a plurality of bolts 9 with seal rings 7 and 8 interposed on the inner periphery of the upper part of the lower member 6. ing.

Inside such a casing, there are a filter section 10 for removing compressor oil and dust, and a dryer section 11 having the desiccant 2 and removing water or humidity. The filter section 10 has a ring-shaped filter 12, and the filter 1
2 is supported by a support member 13, and a filter inlet space 14 is formed on the outside of the filter 12, and a filter outlet space 15 is formed on the inside. Further, the desiccant 2 of the dryer section 11 is filled inside the drying cylinder 16. The drying tube 16 is placed on the bottom of the casing with the filter section 10 at its bottom. In this case, the upper edge of the drying tube 16 fits into the inner periphery of the upper member 5, and the outer periphery fits tightly into the seal ring 8. Therefore, inside the casing, there is an outflow space 18 in the upper part of the drying cylinder 16 that communicates with an outflow port 17 provided at the center of the upper member 5, and a drying space 18 that communicates with an inlet 19 provided at the upper side of the lower member 6. An inflow space 20 on the side circumference of the cylinder 16 is airtightly divided.

Therefore, the compressed air discharged from the air compressor 21 and flowing into the dryer 3 through the inlet 19 first enters the filter inlet space 14 through the inlet space 20 around the side of the drying cylinder 16, and then enters the filter inlet space 14. The water is subjected to a filtering action by the filter 12 while reaching the outlet space 15, and then moisture and the like are removed in the dryer section 11, and flows out of the dryer 3 through the upper outlet space 18 and the outlet 17. In addition, a stop plate 22 having a large number of holes and a first check valve 23, and a throttle passage 24 that bypasses the check valve 23 are provided in the outflow port 17 from the outside to the inside. ing. Also,
Since the desiccant 2 is a granular material, partitions 26 and 27 based on metal porous plates 25 are provided at the top and bottom of the drying cylinder 16 into which it is placed, respectively. In this case, the upper partition 26 is connected to the spring 2
It is held down by 8.

The upper part of the upper member 5 including the outlet 17 is covered by a member 30 constituting a purge reservoir 29. There is an outward flange 31 at the lower end opening of the reservoir component 30, and the flange portion is integrally attached to the upper member 5 with a seal ring 32 interposed therebetween. A piping connection port 33 is provided on the side of the reservoir component 30, and the piping connection port 33 is connected to the second check valve 2 in question.
00 to the main reservoir 34.
Therefore, part of the compressed air flowing out from the outlet 17 on the side of the dryer 3 is stored in the purge reservoir 29 for regeneration, and the remainder is stored in the main reservoir 34. And main reservoir 3
The compressed air in 4 is used as an operating source for external equipment such as an air brake device.

On the other hand, the housing of the drain valve 4 , that is, the main body 35 of the drain valve 4 is provided integrally with the lower member 6 at the lower part of the lower member 6 , which forms the casing of the dryer 3 . A cylinder hole 36 is provided inside the main body 35 of the drain valve 4 . The cylinder hole 36 communicates with the control port 38 through a passage 37 extending to the left side, and communicates with the inside of the dryer 3 through a passage 39 extending to the right side on the other hand.
A plug 40 is inserted into the cylinder hole 36, and a control piston 41 is slidably disposed on the inner peripheral side of the plug 40. The control piston 41 has a pressure receiving surface 41a at one upper end, and the pressure receiving surface 41a receives a pneumatic signal from the pressure governor 42 through the control port 38. Further, a valve member 43 made of an elastic material is attached to the other end of the lower side of the control piston 41.
This valve member 43 constitutes a valve portion of the drain valve 4 together with a tapered valve seat 44 provided on the plug 40 side. The control piston 41 is pushed upward by the biasing force of the spring 45 when the air pressure in the main reservoir 34 does not reach a predetermined value. When the air pressure in the main reservoir 34 reaches a predetermined value, the pressure governor 42 The piston 41 moves downward in response to a pneumatic signal from. Due to these actions, the drain valve 4 is opened and closed.

Now, in this invention, as the second check valve 200 surrounded by the broken line, one having a high valve opening pressure is used. Conventionally, purge reservoir 29 and main reservoir 3
4 (including the opening pressure of the second check valve in the middle) is at most 0.2 to 0.3 in terms of pressure.
Kg/cm ² (normally 0.2 to 0.5 Kg/cm ² , but set to 0.2 to 0.3 Kg/cm ² to reduce flow path resistance, etc.), whereas in this invention, the second reverse The opening pressure of the stop valve 200 is set to, for example, 0.5 to 1.5 kg/cm ² . The set value ΔP of the valve opening pressure can be determined by taking into account the drying capacity of the desiccant 2, the discharge capacity of the air compressor 21, and further legal regulations regarding pressure vessels. Normally, in order to obtain a sufficient regeneration effect, the air pressure in the purge reservoir 29 is determined to be as high as possible within a range that does not exceed the upper limit pressure of 10 kg/cm ² allowed for a low-pressure container. The opening pressure of the second check valve 200 can be easily and easily set by replacing the valve or by replacing the spring that applies the closing force to the valve.

Here, if the pressure of the compressed air stored in the main reservoir 34 is P, then the purge reservoir 2
9 becomes higher (P+ΔP) by the valve opening pressure ΔP of the second check valve 200. Therefore, if the capacity of the purge reservoir 29 is V,
According to this invention, more compressed air for regeneration can be secured by ΔP·V. For example, if the normal valve opening pressure is 0.2 kg/cm ² and is increased to 1.2 kg/cm ² by applying the present invention, the amount of air in the purge reservoir 29 will double compared to the conventional one.

As described above, in the present invention, the opening pressure of the second check valve 200 is increased and the purge reservoir 29
Since the pressure of the dry compressed air stored in the main reservoir 34 is set to be higher than that in the main reservoir 34 by a predetermined value, more compressed air for regeneration can be secured without increasing the capacity of the purge reservoir 29. Can be done. Therefore, the purge reservoir 29
It is possible to effectively avoid installation problems caused by increasing the size. Further, according to the present invention, the amount of regenerated air is increased by changing the second check valve 200, so that it can be easily and easily applied to conventional drying equipment. Can be applied.

Although this invention has been described above based on examples,
It goes without saying that the present invention is not limited to the embodiments described above, and can be modified in various ways without departing from the spirit thereof. For example, the present invention can be applied not only to a drying device in which the dryer 3 and the purge reservoir 29 are integrated, but also to a device in which they are separated.

[Brief explanation of the drawing]

The drawing shows one embodiment of the present invention, and is a piping diagram including a cross-sectional structure of a drying device. 1... Compressed air drying device, 2... Desiccant, 3...
...Dryer, 4...Drain valve, 12...Filter,
17... Outlet, 19... Inlet, 21... Air compressor, 23... First check valve, 24... Throttle passage, 29... Purge reservoir, 34... Main reservoir, 38... Control port, 42...
Pressure governor, 200...second check valve.

Claims (1)

[Claims] 1. A dryer that dries compressed air from an air compressor using a recyclable desiccant, and a part of the compressed air from the dryer is stored for regeneration and the remaining part is supplied to a main reservoir. a purge reservoir, a drain valve that connects the air compressor side of the desiccant to the outside air in response to a signal from the outside, and a drain valve provided between the inside of the dryer and the inside of the purge reservoir for backflow to the desiccant side. a first check valve that prevents the
Compressed air has a throttle passage that constantly communicates both sides of the check valve, and a second check valve that is provided between the inside of the purge reservoir and the inside of the main reservoir to prevent backflow to the purge reservoir side. In the drying device, the necessary amount of compressed air for regeneration is secured by setting the opening pressure of the second check valve to a predetermined high value exceeding 0.5 kg/cm ² in pressure conversion. A method for securing compressed air for regeneration in a compressed air drying device, characterized in that: 2. Regeneration in the compressed air drying apparatus according to claim 1, wherein the opening pressure of the second check valve is approximately 1 kg/cm ² higher in pressure terms than the opening pressure of the first check valve. How to secure compressed air for use.