JPH0640943B2 - Compressed air source device - Google Patents

Description

TECHNICAL FIELD The present invention relates to a compressed air source device including a compressed air drying device, and is particularly suitable for a vehicle.

[Conventional technology]

As a device of this kind, conventionally, it has been used in practice.
There is one described in Japanese Patent No.

The compressed air source device disclosed herein is used, for example, as a pneumatic booster connected to a master cylinder in a vehicle brake system, or as a pressure source for a pneumatic circuit such as an air brake device. , Having a compressed air drying device containing a resorbable adsorbent therein, and introducing compressed air discharged from the air compression device into the compressed air drying device to pass through a layer of the adsorbent for drying. Let The dried compressed air is once stored in the compressed air storage tank device and is consumed by the pneumatic circuit as needed.

[Problems to be solved by the invention]

By the way, since the capacity of the adsorbent housed in the compressed air drying device decreases due to moisture absorption, a compressed air storage tank (purge tank) for regeneration is usually provided so that the compressed air for regeneration is loaded when the air compression device is loaded. A part of the dry compressed air that has passed through the compressed air drying device is stored in the storage tank, and the release valve provided at the bottom of the compressed air drying device is opened by a command to dry compressed air from the regeneration compressed air storage tank. The compressed air that has been dried is caused to flow backward in the device to regenerate the adsorbent.

However, in the above-mentioned conventional one, at the start of the load cycle after the end of the regeneration cycle (purge cycle or unload cycle), the compressed air discharged from the air compression apparatus is a compressed air drying apparatus whose internal pressure is at the atmospheric pressure level. The flow velocity of the compressed air that has flowed into the compressed air is extremely high, and therefore, even if the oil content in the compressed air that has flowed into the compressed air drying device is once removed by the filter device that is arranged in the preceding stage of the adsorbent layer in the compressed air drying device. There is a problem that it is blown off directly and penetrates into the adsorbent layer to reduce the capacity of the adsorbent. In particular, immediately after restarting the load cycle, a large amount of oil temporarily enters due to the oil up of the air compression device at the time of unloading, which is a serious problem.

The present invention has been made to solve the above-mentioned conventional problems, and there is a risk that oil components in the compressed air adhering to the filter device in the compressed air drying device will be blown off by the compressed air and enter the adsorbent layer. It is an object of the present invention to provide a compressed air source device that is capable of preventing deterioration of the adsorbent due to the above oil content and the like.

[Means for solving problems]

In order to achieve the above object, the present invention is a valve device that switches between the inside of a compressed air drying device and the inside of a compressed air storage tank device according to a command from a control device for controlling the internal pressure of the compressed air storage device within an allowable level range. And the compressed air is supplied from the compressed air storage tank device to the inside of the compressed air drying device when the restart of the air compression device is started.

Example of Invention

In the figure, reference numeral 1 is a compressed air drying device, which is provided with an outer container 5 consisting of a main body 2 and an upper lid 4 connected to the main body 2 by a bolt 3, and the upper surface of the upper lid 4 is placed on the outer container 5. The bottom regenerating tank 6 is connected by bolts 3. In the upper part of the peripheral wall of the main body 2, compressed air inlets 7 and 8 are provided.
However, a control port 9 is formed at the bottom of the peripheral wall, and the upper lid 4 is opened toward the inside of the regeneration tank 6 and the throttle passage 10 is formed.
And an outlet 12 communicating with the inside through a check valve 11. In addition, the outlet 1 is provided above the peripheral wall of the regeneration tank 6.
3 is provided. The outer container 5 houses a drying cylinder 14 and filter devices 15 and 16 in its inner space.
The drying cylinder 14 accommodates a regenerable adsorbent 17, and a projection 18 protruding outward from the center of the bottom is fitted into a boss 19 protruding to the center of the bottom of the main body 2, and an opening at the upper end is recessed on the inner surface of the upper lid 4. The compressed air passage 21 is fixed between the outer container 5 and the inner peripheral surface of the outer container 5 by being fitted into the outer container 5. The adsorbent 17 is a drying cylinder 14
The filter is placed on a plurality of seats 22 formed to project on the inner surface of the bottom of the container and is filled up to a predetermined height on a filter member 24 that covers the porous partition plate 23. On the upper surface of the layer, a porous pressing plate 26 is provided via a filter member 25. It is placed and receives a pressing force by a spring 27 interposed between the perforated pressing plate 26 and the inner recess 20. The filter device 15 is fixed between the bottom of the drying cylinder 14 and the bottom of the outer container 5 so as to cover the outer surface of the bottom of the drying container 14, and the compressed air passage 21 has the filter device 15 inside the outer container 5. A cylindrical passage for guiding compressed air to the lower surface of the filter device 15 via a space formed between the surface and the surface. The filter device 16 is provided in the compressed air passage 21 so as to surround the bottom of the drying cylinder 14.

A vertical passage 29 that opens toward the compressed air passage 21 is formed around the raised portion 28 that is raised by forming the boss portion 19 at the center of the bottom of the outer container 5, and inside the raised portion 28. A cylindrical space 31 communicating with the discharge cylinder portion 30 protruding to the lower surface of the outer container 5 is formed.

A plug 34 accommodating the control piston 33 of the discharge valve 32 is tightly fitted in the cylindrical space 31.
4 is a radial passage 35 continuous with the lower end of the vertical passage 29.
A downward concave portion 36 having a tapered inner bottom surface is formed below the passage 35, and a valve hole 37 facing the inner end of the passage 35 is opened at the center of the tapered inner bottom surface 36a. The control piston 33 defines a control chamber A that communicates with the control port 9 between the control piston 33 and the upper bottom portion of the cylindrical space 31 at the pressure receiving portion 38 at the upper end that slides on the plug 34, and has a tapered inner bottom surface 36a at the lower end. A valve member 39 serving as a valve seat is attached by a bolt 40 and is urged upward by a valve spring 41 so that the valve member 39 is normally in a position to be seated on the tapered inner bottom surface 36a.

The inlet 7 of the compressed air drying device 1 having the above-described configuration is provided with a pipe line 50
Is connected to the discharge port of the air compression device 51, and the outlet 13 of the regeneration tank 6 is connected to the compressed air storage tank device 5 through a pipe line 53 in which a check valve 52 having the outlet direction as a check direction is interposed.
4 is connected. Further, a check valve device 55 is connected to the control port 9 by screwing one of the ports. The check valve device 55 includes an input port 55a to which a pressure signal from a control device (hereinafter referred to as a governor) 58 is introduced through a pipe 57, the input port 55a and the check valve 5.
In addition to the output port 55b that communicates via the output port 6, the output port 55 that communicates through the input port 55a and the passage 55c.
d and 55e, the output port 55b is connected through a conduit 59 to an unloader port 51a of an unloader device (not shown) incorporated in the air compressor, the output port 55d is directly connected to the control port 9, and the output port 55e is connected to a conduit 60. Through the air-operated valve device 62. Check valve 56
The valve body 56a has a throttle hole 56b and is urged by a valve spring 56c to normally close the valve hole 56d. The governor 58 is connected to the compressed air storage device 54 through a pipe 61, monitors the pressure in the compressed air storage device 54, and when the internal pressure reaches the first set pressure P1, a signal pressure (unload command and Is generated, and the second set pressure P is generated.
When the pressure drops to 2 (<P1), the signal pressure is stopped from being sent, and the sent compressed air is discharged.

The internal space 6 of the cylindrical main body 63 of the air operated valve device 62
4, a valve piston 65 is slidably accommodated, an input port 66A and a control port 66B are provided at both ends (upper end and lower end), and the compressed air drying device 1 is provided at the side.
An output port 67 that is screwed into and connected to the inlet 8 of the check valve 68 is formed in the outlet port 67 of the check valve 68 and a valve spring 68 that biases the valve body 68a toward the valve hole 68c.
b is stored. The valve piston 65 is an input port 66
A valve member 70 having the inner peripheral surface of A as a valve seat 69 is provided on one end side, and the pressure receiving portion 65a on the other end side is housed in the main body 63 with the control port 66B side, and is controlled by the valve spring 71. The valve member 70 is normally urged toward the port 66B so that the valve member 70 is separated from the valve seat 69. This air valve device 62
The input port 66A is connected to the compressed air storage device 54 through the line 72, and the control port 66B is connected to the output port 55e of the check valve device 55 through the line 60. In the figure, 73 to 76 are sealing members.

[Action]

 Next, the operation of the apparatus of this embodiment will be described.

In a steady state where the governor 58 does not generate a signal pressure (during governor exhaust), the internal pressure of the compressed air storage tank device 54 is applied to the input port 66A of the air operated valve device 62, and the control port 66 is operated.
In the non-pressurized state of B, the valve piston 65 is at the position shown and the check valve 68 is closed. The compressed air discharged by the air compression device 51 is introduced into the outer container 5 through the pipe line 50 and the inlet 7 of the compressed air drying device 1. The compressed air introduced into the outer container 5 flows down through the compressed air passage 21 and is filtered by the filter device 16 and then by the filter device 15, and then enters the drying cylinder 14 to receive the adsorbent 1
7 rises in the bed, and moisture or the like is removed during this time to become dry compressed air, which reaches the outlet 12 through the check valve 11, a part of which is filled in the regenerated compressed air storage tank 6 and the other of which is provided by the conduit 53. Is introduced into the air storage device 54 and stored therein.

Internal pressure of compressed air storage device 54 (hereinafter referred to as tank pressure)
Rises and reaches the first set pressure P1, the governor 58
Generates a signal pressure, which opens the check valve 56 of the check valve device 55 and is connected to the unloader port 51a, and the control port 9 of the compressed air drying device 1 and the air operated valve device 62. It is supplied to the control port 66B and the regeneration cycle (purge cycle) is started.

The signal pressure supplied to the control port 9 is introduced into the control chamber A to push down the control piston 33 against the spring force of the valve spring 41 and open the discharge valve 32. At this time, the tank pressure is applied to the control port 66B of the air operated valve device 62, the valve piston 65 rises in the figure, and the input port 66A is closed. At this time, the check valve 68 remains closed.

Accordingly, when the discharge valve 32 is opened, the compressed air in the drying cylinder 14 is explosively discharged together with the drain from the discharge cylinder 30 as in the conventional case, and then the dry compressed air in the regeneration tank 6 is discharged to the outlet 12 and the throttle. Backflow into the drying cylinder 14 through the passage 10. The compressed compressed air flowing back into the drying cylinder 14 is adsorbent 1
During this period, the adsorbent 17 is regenerated and flows through the filter device 15, the valve hole 37, and the discharge cylinder 14 into the atmosphere.

When the tank pressure of the compressed air storage device 54 drops to the second set pressure P2, the governor 58 switches to the exhaust operation and the signal pressure disappears, so the discharge valve 32 closes, while the air operated valve device. The valve piston 65 of 62 is returned to the illustrated position, and the tank pressure of the compressed air storage tank device 54 is introduced into the main body 63 through the input port 66A. At this time, the check valve 56 of the check valve device 55 is also closed. However, since the check valve 55 has the throttle hole 56b, the pressure supplied to the unloader device (not shown) passes through the throttle hole 56b. Since the air is exhausted slowly, the load start of the air compression device 51 is delayed from the time when the signal pressure disappears, and the inside of the compressed air drying device is at the atmospheric pressure level.

Therefore, the check valve 68 of the air operated valve device 62 is opened by the tank pressure introduced from the compressed air storage tank device 54, and the compressed air drying device 1 from the compressed air storage tank device 54 via the air operated valve device 62. Dry compressed air flows into the inside, and the pressure in the compressed air drying device 1 rapidly rises to almost the tank pressure.

As described above, the loading of the air compression device 51 is delayed, so that after the pressure inside the compressed air drying device 1 rises, compressed air is forced into the compressed air drying device 1 through the inlet 7 from the air compression device 51. Therefore, the compressed air is supplied into the compressed air drying device 1 at a low flow rate.

Thus, in the present embodiment, after the regeneration cycle is completed, the re-operation of the air compression device 51 is delayed by the throttle effect of the check valve 56, while the compressed air is compressed by the operation of the air operated valve device 62. Since the internal pressure in the drying device 1 is increased to almost the tank pressure level of the compressed air storage device 54, and the compressed air is supplied from the air compression device 51 into the compressed air drying device 1 having this internal pressure, it is lowered to the atmospheric pressure level. As compared with the conventional case in which compressed air flows in from the air compression device reloaded into the compressed air drying device 1 as described above, the compressed air flow receives a large resistance. Therefore, the compressed air flowing down through the compressed air passage 21 in the compressed air drying device 1 sequentially passes through the filter devices 16 and 15 at a slow speed, so that the compressed air flow adheres to the filter devices 16 and 15. It is possible to prevent the situation where the oil content etc. is blown away.

〔The invention's effect〕

As described above, the present invention delays the re-operation of the air compression device after the end of the regeneration cycle, during which the dry compressed air from the compressed air storage device is caused to flow back into the compressed air drying device to reduce the pressure in the compressed air drying device. By increasing the air flow rate, the flow velocity of the compressed air flowing into the compressed air drying device from the air compression device after the start of the re-operation can be significantly reduced compared to the conventional one, so that it can be attached to the filter device. It is possible to prevent the oil content and the like from being blown away by the compressed air flowing in after the start of the re-operation and scattered to the adsorbent layer side, and to prevent deterioration due to the oil content and the like.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention. 1 ... Compressed air drying device, 17 ... Adsorbent, 32 ... Release valve, 51 ... Air compression device, 54 ... Compressed air storage device, 58 ... Control device, 62 ... Valve device.

Claims (1)

[Claims] 1. An air compression device for compressing air, a compressed air storage device for storing compressed air from the air compression device, and a device disposed between the compressed air storage device and the air compression device to allow regeneration inside. A compressed air drying device containing a different adsorbent and a command when the pressure in the compressed air storage tank device reaches a relatively high first set pressure, and cancels the command when the pressure falls to a relatively low second set pressure. A control device, an unloader device that invalidates the operation of the air compression device in response to a command from the control device, and the air compression of the adsorbent in the compressed air drying device in response to a command from the control device. A compressed air source device comprising a discharge valve for communicating the device side to the outside and for causing a part of the compressed air in the compressed air storage device to flow back, wherein the inside of the compressed air drying device and the inside of the compressed air storage device are To The control device is connected via a valve device that switches when the command is released, and compressed air is supplied from the compressed air storage device to the inside of the compressed air drying device when the air compressor is restarted. Compressed air source device.