JPH1137917A - Filter testing equipment - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a filter test apparatus capable of accurately determining a service life of a filter and performing a function test of the filter. SOLUTION: A flowmeter 7 and a flow rate control are performed while circulating the electrodeposition paint stored in an electrodeposition tank 1 through a first pipe 2, a filter housing 5 containing a filter 4 and a second pipe 3 by a pump 6. The flow rate of the electrodeposition paint is kept constant by the valve 8. When the clogging of the filter 4 progresses by filtering the electrodeposition paint and the electrodeposition paint becomes difficult to pass,
Since the differential pressure between the upstream pressure of the filter 4 detected by the first pressure gauge 22 and the downstream pressure of the filter 4 detected by the second pressure gauge 23 increases, the controller 9 monitors the differential pressure. Thus, the degree of clogging of the filter 4 can be determined. When the differential pressure reaches a predetermined reference value, the alarm means 25 is operated to issue a notification.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a test apparatus for testing the performance of a filter for filtering a liquid such as an electrodeposition paint for automobiles.

[0002]

2. Description of the Related Art In general, the thickness of an electrodeposition coating film of an automobile body is about 25 μm. Therefore, in order to prevent dust from protruding from the coating film surface, an electrodeposition coating material stored in an electrodeposition tank is required. (E.g., fibers, weld spatter, sealers, iron powder, etc.) having a size of 20 μm or more. So conventionally,
Dust contained in the electrodeposition paint was removed by providing a filter in the middle of a pipe for circulating the electrodeposition paint stored in the electrodeposition tank.

[0003]

By the way, such filters are manufactured by various manufacturers, and the same two filters are used.
Even if the filter has a standard of 0 μm, the service life is different if the manufacturer is different. Therefore, if the filter is replaced while the service life is uniformly determined, the filter that can still be used is replaced needlessly, or the clogging of the filter is destroyed by using the filter with reduced performance due to clogging, There is a possibility of passing large dust that degrades the coating quality.

The present invention has been made in view of the above circumstances, and has as its object to provide a filter test apparatus capable of accurately determining the service life of a filter.

[0005]

In order to achieve the above object, the invention according to claim 1 comprises a pipe connected at both ends to a liquid tank for storing a liquid to be filtered, and a liquid in the liquid tank. Through a pipe, flow control means for maintaining a constant flow rate of liquid flowing through the pipe, and an upstream pressure of a filter provided at an intermediate portion of the pipe and filtering a fluid flowing through the pipe. A first pressure detecting means, a second pressure detecting means for detecting a downstream pressure of the filter, and a filter based on a differential pressure between the upstream pressure and the downstream pressure of the filter detected by the first and second pressure detecting means. And determining means for determining the degree of clogging.

According to the above arrangement, the flow rate of the liquid is kept constant by the flow rate control means while driving the pump to circulate the fluid in the liquid tank through the first pipe, the filter housing and the second pipe. As the clogging of the filter progresses and the fluid becomes difficult to pass, the differential pressure between the upstream pressure of the filter detected by the first pressure detecting means and the downstream pressure of the filter detected by the second pressure detecting means increases. Therefore, the degree of clogging of the filter can be determined by monitoring the differential pressure by the determining means.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, an alarm unit for issuing an alarm in response to a command from the determining unit when the differential pressure becomes equal to or more than a predetermined value is provided. And

[0008] According to the above configuration, it is possible to reliably notify that the clogging of the filter has advanced.

According to a third aspect of the present invention, in addition to the first aspect, a first sample extraction valve for extracting a liquid sample from the upstream side of the filter and a liquid sample for extracting the liquid sample from the downstream side of the filter. And a second sample extraction valve.

According to the above configuration, dust contained in the liquid on the upstream side of the filter extracted from the first sample extraction valve,
By comparing with the dust contained in the liquid on the downstream side of the filter extracted from the second sample extraction valve, the filtration performance of the filter and the destruction state of the eyes of the filter can be confirmed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 to 3 show an embodiment of the present invention. FIG. 1 is an overall configuration diagram of a filter testing apparatus, FIG. 2 is an enlarged view of a main part of FIG. 1, and FIG. 3 is a service life of the filter. FIG.

As shown in FIG. 1, an electrodeposition tank 1 for performing electrodeposition coating of an automobile body stores electrodeposition paint. Electrodeposition tank 1
Is connected to an upstream end of the first pipe 2 and a downstream end of the second pipe 3. A filter 4 (described later) is internally provided between the downstream end of the first pipe 2 and the upstream end of the second pipe 3. A filter housing 5 containing (see FIG. 2) is connected. A pump 6 for circulating the electrodeposition paint in the electrodeposition tank 1 through the first pipe 2, the filter housing 5, and the second pipe 3 is provided at an intermediate portion of the first pipe 2. The second pipe 3 is provided with a flow meter 7 and a flow control valve 8 in series, and a control device 9 comprising a microcomputer controls the flow rate of the electrodeposition coating detected by the flow meter 7 to a predetermined value. The feedback control of the opening of the flow control valve 8 is performed so as to coincide with the following.
The flow meter 7 and the flow control valve 8 constitute a flow control means of the present invention, and the control means 9 constitutes a determination means of the present invention.

As is clear from FIG. 2 together,
The filter housing 5 has a cylindrical housing body 10.
A lower lid 11 that covers the lower surface opening of the housing body 10;
An upper cover 12 covers an upper surface opening of the housing body 10, and a bolt 13 and a nut 14 that press the housing body 10, the lower cover 11 and the upper cover 12 in the axial direction to integrate them. The inner space of the filter housing 5 is
2 is connected to the downstream end of the first pipe 2 via a first joint 15 fixed to the
The joint 16 is connected to the upstream end of the second pipe 4.

The filter 4 formed by forming a cotton filter material or a polypropylene filter material into a cylindrical shape is housed inside a filter housing 5. Filter 4 is bolt 13
The lower surface thereof is in close contact with the upper surface of the lower lid 11 and the upper surface thereof is in close contact with the lower surface of the upper lid 12 while being centered by the spacer 17 provided on the outer periphery of the upper lid 12. Thus, filter 4
A dirty chamber 18 communicating with the first pipe 2 is defined between the outer peripheral surface of the filter and the inner peripheral surface of the housing body 10, and a clean chamber 19 communicating with the second pipe 3 is defined inside the filter 4. Therefore, the electrodeposition coating that has flowed into the dirty chamber 18 from the first pipe 2 passes through the filter 4 from the outside to the inside, is filtered, and then passes through the clean chamber 19 to the second pipe 3.
Leaked to

The first joint 15 and the second joint 16 include:
A first pressure gauge 22 and a second pressure gauge 23 are connected via opening / closing valves 20 and 21, respectively.
The signals 2 and 23 are input to the control device 9. The on-off valves 20 and 21 are closed when the first and second pressure gauges 22 and 23 are not used. The control device 9 determines the degree of clogging of the filter 4 based on the signals of the first and second pressure gauges 22 and 23, outputs the result of the determination to recording means 24 such as a printer, and determines the life of the filter 4. Is activated, the alarm means 25 such as a buzzer is activated.

The first joint 15 and the second joint 16 include:
A first sample extraction valve 26 for extracting the electrodeposition coating before passing through the filter 4 as a sample, a second sample extraction valve 27 for extracting the electrodeposition coating after passing the filter 4 as a sample, and Is provided.

Next, the operation of the embodiment of the present invention having the above configuration will be described.

With the new filter 4 mounted inside the filter housing 5, the pump 6 is driven to deposit the electrodeposition paint inside the electrodeposition tank 1 through the first pipe 2, the filter housing 5 and the second pipe 3. Circulate through. At this time,
The flow rate of the electrodeposition paint detected by the flow meter 7 is a constant value (for example,
The opening of the flow control valve 8 is feedback-controlled by the controller 9 so that the flow rate becomes 20 liters per minute). In this state, the first pressure gauge 22 detects the upstream pressure of the filter 4 and the second pressure gauge 23 detects the downstream pressure.
The detected values are compared in the control device 9. When the filter 4 is not clogged, the electrodeposition coating material can easily pass through the filter 4, so that the differential pressure between the upstream pressure and the downstream pressure becomes relatively small. As the clogging progresses to No. 4, the differential pressure increases.

The graph of FIG. 3 shows the change in the differential pressure with respect to the number of days of use of the filter 4 recorded by the recording means 24. The initial differential pressure of 0.1 kg / m ² was maintained until the third day from the start of the test. It is almost constant, but starts to increase from the 4th day and is set as the reference value on the 6th day as 0.7 kg / m.
^{When the value} exceeds ² , it is determined that the filter 4 is clogged and it is time to replace the filter. When the filter 4 reaches the replacement time, the alarm is activated by operating the alarm means 25. In this embodiment, the reference value is set to 0.7 kg / m ² , but the reference value can be set arbitrarily within a range not exceeding 1.5 kg / m ² .

The differential pressure increases as the flow rate of the electrodeposition paint passing through the filter 4 increases, and the service life of the filter 4 decreases as the flow rate of the electrodeposition paint increases. By keeping the flow rate of the electrodeposition paint constant by the flow meter 7 and the flow control valve 8, it becomes possible to make an accurate determination.

When the filter 4 is clogged and the differential pressure starts to increase, the first sample extraction valve 26 and the second sample extraction valve 27 are opened to sample the electrodeposition paint on the upstream side of the filter 4 and on the downstream side. A predetermined amount (for example, 200 to 300 ml) of the electrodeposition paint sample is taken out and observed.
Specifically, the sample was prepared by sintering a stainless steel wire mesh (5 μm).
m), and the filtration residue is observed with a microscope and photographed. By this visual observation,
Make sure that large particles exceeding the standard pass through the filter 4 because the filter 4 eyes are too large, and that large particles exceeding the standard pass through when the filter 4 eyes are broken due to excessive differential pressure due to clogging. Can be determined. Since destruction of the filter 4 due to clogging is likely to occur when the differential pressure is large, it is desirable that the visual observation be performed at short time intervals as the differential pressure increases.

In this way, since various types of filters 4 of different manufacturers and standards can be tested and their service life can be accurately grasped, there is a problem that filters that can still be used are wasted and clogging occurs. As a result, it is possible to reliably prevent a problem that the paint quality is deteriorated by continuously using the filter whose eyes are destroyed.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various design changes can be made.

For example, in the embodiment, a test of a filter for filtering an electrodeposition paint is illustrated, but the present invention can be applied to a test of a filter for any other use.

[0026]

As described above, according to the first aspect of the present invention, when the filter becomes clogged and the fluid becomes difficult to pass, the upstream pressure of the filter detected by the first pressure detecting means and the pressure of the filter become lower. (2) Since the differential pressure increases between the pressure detected by the pressure detecting means and the downstream pressure of the filter, the degree of clogging of the filter can be determined by monitoring the differential pressure by the determining means. This makes it possible to accurately grasp the service life of various filters and reliably prevent the problem of unnecessarily replacing filters that can still be used and the problem of continuously using filters whose eyes are broken due to clogging. Can be.

According to the second aspect of the present invention,
The fact that filter clogging has progressed can be reliably notified.

According to the invention described in claim 3,
By comparing the dust contained in the liquid on the upstream side of the filter extracted from the first sample extraction valve with the dust contained in the liquid on the downstream side of the filter extracted from the second sample extraction valve, the filtering performance and the filter performance of the filter are improved. You can check the destruction of the eyes of the filter.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a filter testing apparatus.

FIG. 2 is an enlarged view of a main part of FIG. 1;

FIG. 3 is a graph for determining a service life of a filter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrolysis tank (liquid tank) 2 1st piping (piping) 3 2nd piping (piping) 4 Filter 6 Pump 7 Flow meter (Flow control means) 8 Flow control valve (Flow control means) 9 Control device (Determination means) 22 First pressure gauge (first pressure detection means) 23 Second pressure gauge (second pressure detection means) 25 Alarm means 26 First sample extraction valve 27 Second sample extraction valve

Claims (3)

[Claims] 1. A pipe (2, 3) having both ends connected to a liquid tank (1) for storing a liquid to be filtered, and a liquid in the liquid tank (1) circulated through the pipe (2, 3). Pump (6), flow control means (7, 8) for maintaining a constant flow rate of the liquid flowing through the pipe (2, 3), and a pipe (2, 3) provided at an intermediate portion of the pipe (2, 3). , 3)
A first pressure detecting means (22) for detecting a pressure on an upstream side of a filter (4) for filtering a fluid flowing through the filter; a second pressure detecting means (23) for detecting a pressure on a downstream side of the filter (4); (1) Judging means (9) for judging the degree of clogging of the filter (4) based on the differential pressure between the upstream pressure and the downstream pressure of the filter (4) detected by the second pressure detecting means (22, 23). And a filter testing device. 2. An alarm means (2) for issuing an alarm in response to a command from the judging means (9) when the differential pressure becomes equal to or higher than a predetermined value.
The filter testing apparatus according to claim 1, further comprising (5). 3. A first sample extraction valve (26) for extracting a liquid sample liquid from an upstream side of the filter (4);
The filter test apparatus according to claim 1, further comprising a second sample extraction valve (27) for extracting a liquid sample from a downstream side of the filter (4).