Filter device

Patent metadata

Field	Value
Publication number	US-11529581-B2
Application number	US-202016932991-A
Country	US
Kind code	B2
Filing date	Jul 20, 2020
Priority date	Jul 25, 2019
Publication date	Dec 20, 2022
Grant date	Dec 20, 2022

Abstract

A negative pressure-side flow path having a negative pressure-side filter and a positive pressure-side flow path having a positive pressure-side filter are connected in parallel between a first port and a second port, and a shuttle valve is installed between the negative pressure-side flow path and the positive pressure-side flow path, and the first port, thus when a negative pressure is supplied to the first port, the first port is caused to communicate with the second port through the negative pressure-side flow path, and when a positive pressure is supplied to the first port, the first port is caused to communicate with the second port through the positive pressure-side flow path.

First claim

The invention claimed is:

1. A filter device which is installed in a flow path and filters foreign substances from a gas which flows through the flow path to which a pressure selectively switched between a negative pressure and a positive pressure is supplied, the filter device comprising:
a first port for selectively switching between and inputting a negative pressure and a positive pressure; a second port for outputting to an outside the negative pressure and the positive pressure inputted from the first port; and a negative pressure-side filter and a positive pressure-side filter which are disposed between the first port and the second port, and connected in parallel to the first and second ports,
the negative pressure-side filter has a breathable negative pressure-side filter element to filter foreign substances from a gas which flows from the second port to the first port, and the positive pressure-side filter has a breathable positive pressure-side filter element to filter foreign substances from a gas which flows from the first port to the second port,
a shuttle valve is disposed between the first port, and the negative pressure-side and positive pressure-side filters, and
the shuttle valve has a valve disc such that when a negative pressure is supplied to the first port, the valve disc opens communication between the first port and the negative pressure-side filter to output the negative pressure from the second port, and simultaneously blocks communication between the first port and the positive pressure-side filter, whereas when a positive pressure is supplied to the first port, the valve disc opens communication between the first port and the positive pressure-side filter to output the positive pressure from the second port, and simultaneously blocks communication between the first port and the negative pressure-side filter.

2. The filter device according to claim 1 ,
wherein the filter device has a negative pressure-side flow path including the negative pressure-side filter and a positive pressure-side flow path including the positive pressure-side filter between the first port and the second port, and
one ends of the negative pressure-side flow path and the positive pressure-side flow path communicate with the shuttle valve, and the other ends of the negative pressure-side flow path and the positive pressure-side flow path communicate with the second port.

3. The filter device according to claim 2 ,
wherein a constriction portion is formed on a flow path portion in the positive pressure-side flow path, the flow path portion being closer to the second port than to the positive pressure-side filter element.

4. The filter device according to claim 2 ,
wherein the filter device extends along a longitudinal axis, and has a first end and a second end at both ends in an axial direction,
the filter device has a filter main body which includes the negative pressure-side and positive pressure-side filters and extends in the axial direction, a first cap section which includes the first port and the shuttle valve, and is detachably attached to an end on a first end side of the filter main body, and a second cap section which includes the second port, and is detachably attached to an end on a second end side of the filter main body,
the negative pressure-side and positive pressure-side filters are provided extending in parallel to each other in the axial direction in the filter main body, and
both ends of the negative pressure-side and positive pressure-side filters are detachably connected to the first cap section and the second cap section, and thereby ends on a first end side of the negative pressure-side flow path and the positive pressure-side flow path communicate with the shuttle valve, and ends on a second end side of the negative pressure-side flow path and the positive pressure-side flow path communicate with the second port.

5. The filter device according to claim 4 ,
wherein the negative pressure-side filter has the negative pressure-side filter element in a tubular shape extending in the axial direction, a tubular negative pressure-side filter case which inwardly houses the negative pressure-side filter element and forms a negative pressure-side ring-shaped outer flow path on an outer circumferential surface of the negative pressure-side filter element, a negative pressure-side first joint that connects an end on a first end side of the negative pressure-side filter case and the first cap section, and a negative pressure-side second joint that connects an end on a second end side of the negative pressure-side filter case and the second cap section,
in the negative pressure-side first joint, a negative pressure-side first flow path is formed, which allows the shuttle valve and an internal flow path of the negative pressure-side filter element to communicate with each other in the negative pressure-side flow path, and in the negative pressure-side second joint, a negative pressure-side second flow path is formed, which allows the negative pressure-side ring-shaped outer flow path and the second port to communicate with each other in the negative pressure-side flow path,
the positive pressure-side filter has the positive pressure-side filter element in a tubular shape extending in the axial direction, a tubular positive pressure-side filter case which inwardly houses the positive pressure-side filter element and forms a positive pressure-side ring-shaped outer flow path on an outer circumferential surface of the positive pressure-side filter element, a positive pressure-side first joint that connects an end on a first end side of the positive pressure-side filter case and the first cap section, and a positive pressure-side second joint that connects an end on a second end side of the positive pressure-side filter case and the second cap section, and
in the positive pressure-side first joint, a positive pressure-side first flow path is formed, which allows the shuttle valve and the positive pressure-side ring-shaped outer flow path to communicate with each other in the positive pressure-side flow path, and in the positive pressure-side second joint, a positive pressure-side second flow path is formed, which allows an internal flow path of the positive pressure-side filter element and the second port to communicate with each other in the positive pressure-side flow path.

6. The filter device according to claim 5 ,
wherein a constriction portion is formed in a flow path portion, which is closer to the second port than to the positive pressure-side filter element, in the positive pressure-side flow path by setting an effective cross-sectional area of the positive pressure-side first flow path equal to an effective cross-sectional area of the negative pressure-side second flow path, and an effective cross-sectional area of the positive pressure-side second flow path smaller than an effective cross-sectional area of the negative pressure-side first flow path.

7. The filter device according to claim 5 ,
wherein the negative pressure-side filter case and the positive pressure-side filter case are formed of a transparent material so that the negative pressure-side filter element and the positive pressure-side filter element are visible from an outside through the negative pressure-side and positive-side filter cases.

8. The filter device according to claim 4 ,
wherein the shuttle valve has a valve mounting hole which is provided open in the first cap section, a body for flow path formation which is fitted into the valve mounting hole and forms a valve chamber between a leading end and a bottom of the valve mounting hole, and the valve disc disposed in the valve chamber,
a first communication flow path, which communicates with the negative pressur

Assignees

• Smc Corp

Inventors

• Kurihara Mitsuhiro
• Fukushima Kenji

Classifications

• B01D46/2403

  characterised by the physical shape or structure of the filtering element · CPC title

• B01D46/90

  Devices for taking out of action one or more units of multi-unit filters, e.g. for regeneration or maintenance · CPC title

• B01D46/4272 Primary

  Special valve constructions adapted to filters or filter elements · CPC title

• B01D2279/51

  in clean rooms, e.g. production facilities for electronic devices, laboratories · CPC title

• B01D46/58 Primary

  connected in parallel · CPC title