JPH0244824Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial application field The invention is used for gas filters that are installed in compressed gas piping to capture oil mist, dust particles, etc. in compressed gas, and for clean room air supply equipment. This invention relates to a time management device for gas filters to know when to replace HEPA filters, etc.

Prior Art Taking the case of an air filter for the purpose of cleaning compressed air as an example, the conventional device for knowing when to replace the air filter is as shown in Fig. 3.
An air filter 3 is installed between the discharge side flow path 31 connected to the air compressor side and the supply side flow path 32 to the air equipment etc.
3 is inserted to force compressed air to pass through, clean it by removing oil mist, etc., and supply it to the load side. Over time, the filter becomes clogged with solid particles and oil, reducing its filtration ability, and the oil etc. that have been so diligently collected are scattered again, making it no longer able to fulfill its role.

For this purpose, conventionally, a differential pressure gauge 30 is attached via pressure introduction pipes 34 and 35 connected to the discharge side flow path 31 and the supply side flow path 32, respectively, and the air filter 3
An air filter management device is known that is configured to measure the pressure drop due to No. 3 and, when the pressure drop exceeds a certain level, remove the filter case 36 and replace it with a new air filter.

However, this type of device is effective when the object to be filtered out is particulate and it can be used to the extent that the air filter becomes clogged.
As with the compressed air in the above example, the object to be filtered is mainly
In the case of oil mist, there is almost no change in the differential pressure gauge 30 even if the air capturing ability decreases, and the differential pressure gauge cannot tell whether the air filter is dirty. In addition, even if the target is not oil mist, the display on the differential pressure gauge will change due to sudden changes in load or when there is almost no load. It is very rare to use it in a clogged state. For this reason, it is not always possible to know the appropriate time to replace the filter with a differential pressure gauge, so even if the air filter is equipped with the above device, it is recommended that the air filter be replaced with a new one at regular intervals. The common method is to manage

Structure of the invention The present invention has been developed in response to the above-mentioned circumstances, and its gist is that a gas filter is installed in the gas flow path near the installation part of the gas filter, which is removably interposed in the middle of the gas flow path. A gas filter management device is comprised of a pressure switch installed to sense atmospheric pressure and energize, and a totalizer that is energized via the pressure switch and measures the energization time.

Hereinafter, the present invention will be explained in detail based on an embodiment in which the present invention is applied to an air filter for compressed air.

FIG. 1 shows an embodiment of the present invention as a compressed air air filter management device, in which a discharge side pipe 3 connected to a discharge pipe (not shown) of an air compressor.
and an air filter attachment part 10 airtightly connected to the supply side piping 4 to the air equipment through connection ports 5 and 6, respectively.
The inside of the discharge side pipe 3 is connected to the discharge side pipe 3 by a tubular partition wall 7.
The partition wall 7 is divided into a space 3a communicating with the supply side piping 4 and a space 4a communicating with the supply side piping 4, and hanging downward
An air inlet 8a of an air filter 8 made of a cylindrical layer of glass fiber, filter paper, urethane foam, etc. is screwed into the lower end of the filter. Air filter mounting part 10
The housing 9 is divided into upper and lower halves with flanges 9c and 9d as boundaries, and is configured such that the lower housing 9b enclosing the air filter 8 can be removed from the upper housing 9a to replace the air filter. . 11 is a trap for discharging oil droplets and the like. The above configuration is no different from the conventional one. The feature of the present device is that the upper housing 9
A pressure outlet 12 is provided at a, and when the pressure inside the discharge side piping reaches a certain level or higher,
The device is equipped with a pressure switch 1 that closes a power supply terminal, and an integrator 2 that is energized by the pressure switch and totals the energization time. For example, as shown in Figure 2, in an integrated meter, stable vibrations oscillated by a crystal oscillation circuit are applied to a frequency divider circuit, and the signal frequency-divided by the frequency divider circuit is sent to the liquid crystal panel through a drive circuit. Something that displays the total amount of time the air filter actually operates.
Alternatively, as shown by the broken line, the drive circuit drives the step motor of a timer switch for which the allowable operating time has been set in advance, and a warning lamp lights up when the predetermined time has elapsed. Any known method can be used as long as it does not impair the purpose. The present invention is applicable not only to high-pressure piping such as compressed air piping, but also to relatively low-pressure gas flow paths such as air conditioner ducts in clean rooms, and negative pressure flow paths such as vacuum furnaces used for heat treatment of metals. Needless to say, it is something that can be adapted. Furthermore, the present invention can naturally be applied to a flow path for nitrogen gas, etc.

Effects Because there was no appropriate means to know when to replace the air filter, manufacturers of these devices traditionally required replacing the air filter at regular intervals in order for air equipment and clean rooms to operate normally. However, this is left up to the user's own management, making it difficult to carry out properly.Furthermore, these replacement periods are set based on the assumption of average operating time. Therefore, there were complaints that even if the filter was replaced as prescribed, the replacement time would be too late or too early depending on the length of the operating time. Furthermore, with a differential pressure gauge,
There was no reliable way to check when it was time to replace the filter. According to the present invention, it is possible to decide when to replace such a gas filter according to the actual usage time, so it is possible to replace the filter with just the right amount. Set the time to the integration timer,
If used to warn when it is time to replace the gas filter, it has the effect of more reliable time management of the gas filter.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing one embodiment of the present invention, FIG. 2 is a block diagram showing an example of the circuit configuration of the apparatus of the present invention, and FIG. 3 is an explanatory diagram showing an example of the prior art.

Claims (1)

[Scope of utility model registration request] A pressure switch is installed near the installation part of the gas filter, which is removably inserted in the middle of the gas flow path, to sense the atmospheric pressure in the gas flow path and close the power supply circuit. A gas filter management device comprising a totalizer that is energized and totalizes the energization time.