US3773043A

US3773043A - Respirator having a mouthpiece arranged laterally of the filter

Info

Publication number: US3773043A
Application number: US00197266A
Authority: US
Inventors: K Wachter
Original assignee: Draegerwerk AG and Co KGaA
Current assignee: Draegerwerk AG and Co KGaA
Priority date: 1970-11-20
Filing date: 1971-11-10
Publication date: 1973-11-20
Anticipated expiration: 1990-11-20
Also published as: NL7115332A; FR2114531A5; DE2057093B2; GB1370491A; NL167599C; BE774273A; DE2057093A1

Abstract

A respirator includes a housing with an annular interior wall in which is mounted a filter. An outer wall of the housing has an inlet at one side and a flow space from the inlet through a converging passage defined by a cover on one end of the filter and then through a diverging passage after flow through the filter. The diverging passage communicates at the opposite side of the filter with a mouthpiece which is advantageously covered by removable enclosure when not in use.

Description

United States Patent [1 1 Wachter Nov. 20, 1973 1 RESPIRATOR HAVING A MOUTHPIECE ARRANGED LATERALLY OF THE FILTER [75] Inventor: Karl-August Wachter, Lubeck,

Germany [73] Assignee: Dragerwerk Aktiengesellschaft,

Lubeck, Germany [22] Filed: Nov. 10, 1971 [21] Appl. No.: 197,266

[30] Foreign Application Priority Data Nov. 20, 1970 Germany P 20 57 093.8

[52] US. Cl. 128/147 [51] Int. Cl A621) 7/00 [58] Field of Search 128/147, 146.6, 142.6,

128/201, 212, 208, 140 R, 141, 142.4, 146, 146.3; 55/512, 516, 518, 520, DIG. 35, 515

[56] References Cited UNITED STATES PATENTS 2,295,296 9/1942 Schmidt 128/1466 X 2,610,624 9/1952 Haller et a]. 128/147 Primary ExaminerRichard A. Guadet Assistant Examiner-Lee S. Cohen Attorney-John J. McGlew et al.

[5 7 ABSTRACT A respirator includes a housing with an annular interior wall in which is mounted a filter. An outer wall of the housing has an inlet at one side and a flow space from the inlet through a converging passage defined by a cover on one end of the filter and then through a diverging passage after flow through the filter. The diverging passage communicates at the opposite side of the filter with a mouthpiece which is advantageously covered by removable enclosure when not in use.

10 Claims, 2 Drawing Figures Patented Nov. 20, 1973 3,773,043

RESPIRATOR HAVING A MOUTHPIECE ARRANGED LATERALLY OF THE FILTER BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates in general to breathing devices and, in particular, to a new and useful respirator with an interior wall holding a filter and with air flow from an inlet on one side through the filter to its opposite end and then to a mouthpiece at the opposite side which has a bite cam for engagement by a persons mouth.

2. Description of the Prior Art Small size respirators which may be carried in a pocket of the wearer, and which contain a filter which is lodged in a relatively flat housing are known. The Hat housing is filled up over its flat cross-section by a filter mass which is closed off on both sides by a perforated metal sheet. On the gas outlet side, the housing is closed off by a cover which extends laterally, and includes a connection piece for a mouthpiece. Viewed in the direction of flow of the air through the filter material, the mouthpiece lies laterally next to the filter material. The cover includes a central portion which carries the mouthpiece and the next valve is located in this location. The housing may be opened on the air inlet side so that the perforated metal sheet holding the filter material forms the outer boundary. It is also known to provide a respirator construction which includes a filter outlet side which is closed off by an arch, a cover which is provided in the central portion with openings which are covered by a membrane which acts as an inhalation valve (U.S. Pat. No. 2,610,624). U. S. Pat. No. 2,626,678 also shows a construction in which the filter is under vacuum and is hermetically sealed on the filter inlet side by a cover. The cover rests against a closure ring against which it is pressed by the air pressure and it is opened by a lever connected therewith.

A disadvantage of all of the known constructions is that they require the manufacture of many individual parts, and they are costly to make. Because of the deflection of the air which is circulated therethrough, the known respirators have a relatively high resistance on the filter outlet side. Moreover, the flow through the filter is irregular. In wearing such devices, the air inlet aperture is directly in front of the users chest so that at certain head positions, the inlet aperture may rest against the wearers suit, and this makes breathing difficult. The known devices have complicated closures for the inhalation aperture.

SUMMARY OF THE INVENTION In accordance with the invention, there is provided a respirator of simple construction and low costs, which may be manufactured very easily and assembled and stored without difficulty. The device is made as small as possible so that it can be carried in a pocket of the user. The respiration flow distance of the device is low in all positions of use. The flow through the respirator filter is uniform. For this purpose, the respirator comprises a housing with an interior annular wall which carries a filter and which is connected at its one side to an inlet which communicates with a converging passage to the full filter area, for flow through the filter to the opposite end. The mouthpiece positioned at the opposite side connects through a passage which diverges outwardly to the mouthpiece from the opposite end of the filter. The cover for the housing forms the coverging passage on the inlet end of the filter and the diverging passage toward the mouthpiece on the mouthpiece end. The filter is arranged so that the flow is across its major dimension and cross-section through a relatively shallow depth filter. The flow resistance of such a construction is low and the flow through the filter is uniform. The inlet aperture of the filter can be hermetically closed without difficulty and it is located so that the inlet aperture is not blocked in the common positions of use.

A favorable form of the invention is to arrange the air inlet aperture on the side opposite to the mouthpiece. This has the advantage that the wearer instinctively recognizes the position of the inlet aperture immediately and this facilitates the handling of the device.

In a further embodiment of the device, the housing contains an internal adaptor flange of circularly cylindrical formation which provides a mounting for the filter material, and the outer housing wall is made ovalshaped so that it extends beyond each end of the filterholding parts. The air inlet is arranged in one end of the outer housing and the mouthpiece is arranged in the opposite end, and the passage space defined between the air inlet and the filter ring, provides an inlet flow space while the opposite side provides an outlet flow space to the mouthpiece. The ring flange for holding the filter is advantageously made of one piece with the housing, and with the mouthpiece connection on one side thereof. One of the cover portions on an end of the filter may also be made integral with the housing and the other cover area may comprise a readily connectable part. Otherwise, the two cover parts may be made of identical configuration. They are applied over opposite ends of the filter in an opposite manner.

The mouthpiece advantageously carries a nose clamp therein which may be removed by stretching a connecting spring in order to immediately position it in a location for use.

Accordingly, it is an object of the invention to provide an improved respirator construction which includes a flat housing having an internal mounting ring for a filter but with an inlet on one side which connects through a passage to one end of the filter, and a mouthpiece at the opposite side which connects through a connecting passage to the opposite end of the filter.

A further object of the invention is to provide an improved filter construction which includes a flat housing having an internal mounting ring of circularly cylindrical form carrying a filter and with the outer wall thereof forming a crescent-shaped flow space at each side, one side being connected to an inlet and the opposite side being connected to a mouthpiece.

A further object of the invention is to provide a respirator which is simple in design, rugged in construction, and economical to manufacture.

The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference should be had to the accompanying drawing and descriptive matter in which there is illustrated a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWING In the Drawing:

FlG. l is a vertical sectional view of a respirator constructed in accordance with the invention; and

FIG. 2 is a horizontal sectional view of the respirator.

GENERAL DESCRIPTION OF THE PREFERRED EMBODlMENT Referring to the drawings in particular, the invention contained therein, comprises a respirator housing 1, which is advantageously an injection molding of plastic or similar material, and which includes an integrally formed mouthpiece part 2 extending outwardly from one side thereof. The interior of the housing includes an annular cylindrical wall for a filter mounting ring 5 in the interior of which is mounted a filter 3. The filter 3 may be formed of a metal pot 4, which may be injection-molded into the housing 1. The filter material 6 is mounted within the metal pot 4 and is held between two cover screens for perforated plates 7, 7'. One of the cover screens 7 may be formed in the molding process. It is also possible to produce the filter pot 4 of the filter 3 directly in the molding process.

In accordance with a further feature of the invention, the housing 1 is made with an exterior oval-shaped wall so as to define an air inlet space 9 at one side, and an air discharge flow space 10 at the opposite side, both spaces being of a crescent-shaped cross-section. An air inlet aperture 8 is arranged centrally to connect into the inlet space 9, and this is diametrically opposite the mouthpiece connection piece 2, which communicates with the outlet space 10.

After the filling of the filter 3 for the insertion of the filter, as the case may be, covers 12 and 12 are arranged at respective opposite ends of the filter. The covers 12 and 12' are of identical configuration but are oppositely positioned, and the cover 12 defines an inlet flow space 11a, which gradually converges toward the filter 3, whereas the cover 12' defines an outlet flow space 11b which diverges outwardly into communication with the outlet space 10. The

covers

12 and 12 may be connected to the housing by a gas-tight connection, such as gluing or welding. Because the air flow inlet space 11a diminishes in cross-section in the flow direction, and the air flow space lib at the opposite end of the filter 3 increases in cross-section in the flow direction, the flow considerations are favorable so that the flow through the filter is uniform.

The mouthpiece 2 carries a rubber mouthpiece 13 with bite cam 14. In order to save space in packing of the device, the mouthpiece carries a spring 15, which is engaged in the interior of the mouthpiece l3, and which is connected at its outer end to a nose clamp 20.

The air inlet-opening 8 is closed by a plug 1.61, and the mouthpiece 13 is closed by a cap l7 when the device is not in use. Both of these elements are connected together by a closure band l8 which encircles the respira tor. The plug 16, the cap 17 and the band l8 may form a common molded part so that they remain intercon' nected and do not become disassociated. The closure band 18 is provided with a closure for the ends (not shown). So that it will not be damaged, protruberances 19 are provided on one or both sides of the closure on the cover 12 and i2 so that the device is protected from damage from wearing. The closures in and 17 close the device completely gas-tight and in a satisfactory manner, and permanently, even when it is stored for a long time. The entire form of the respirator is such that it easily slides over all objects and forms no resistance. Sharp corners and edges are avoided. The device can be accommodated without trouble and resistance in a coat or a smock pocket.

For use, the wearer merely removes the closure band l8 and takes off the

closures

16 and 17. He places the nose clamp 20 over his nose and pushes the respirator mouthpiece into his mouth. The device is suitable principally as an escape filter device.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. A respirator comprising a housing having a flat cylindricai filter receiving wall defining a space therein for a filter, a filter within said receiving wall space, a mouthpiece in said housing adjacent to and exterior of one end of said filter receiving wall, an air inlet defined in said housing adjacent to and exterior of the diametrically opposite side of said filter receiving wall, and cover means overlying each side of said space and spaced from said filter receiving wall and defining a flow space from said inlet on one end of said filter with gradually narrowing flow space and a flow space on the opposite end of said filter with gradually widening flow space area to said mouthpiece.

2. A respirator, according to claim 1, wherein said cover means includes a separate cover on each end of said housing, said covers being of identical configuration but being arranged in a reverse manner on respective ends of said filter.

3. A respirator, according to claim 1, including a nose clamp connected to said mouthpiece and being inscrtable therein.

4. A respirator, according to claim 1, wherein said cover means includes a protuberance thereon on each side forming a protection.

5. A respirator comprising a housing, a filter mounted in said housing, a mouthpiece in said housing adjacent one side of said filter, an air inlet defined in said housing adjacent the opposite side of said filter, and cover means on each end of said housing defining a flow space from said inlet on one end of said filter with gradually converging walls and a flow space on the opposite end of said filter with gradually diverging walls to said mouthpiece, said housing including an outer oval-shaped wall and an inner circularly cylindrical wall centered within the oval-shaped housing, said filter being disposed within the circular ring-shaped wall, said inner ring-shaped wall defining a crescent-shaped flow space at each side adjacent said mouthpiece and said inlet respectively.

6. A respirator, according to claim 5, wherein said ring-shaped wall is made integral with said housing and said mouthpiece.

7. A respirator, according to claim 5, wherein said filter includes a perforated wall at one end formed integrally with said ring-shaped wall.

8. A respirator comprising a housing, a filter mounted in said housing, a mouthpiece in said housing adjacent one side of said filter, an air inlet defined in said housing adjacent the opposite side of said filter, and cover means on each end of said housing defining a flow space from said inlet on one end of said filter with gradually converging walls and a flow space on the opposite end of said filter with gradually diverging walls to said mouthpiece, a cap extending over said mouthpiece, said air inlet aperture having a closure cap thereover, and an encircling band connecting said air inlet closure cap and said mouthpiece cap.

9. A respirator, comprising a housing having an ovalshaped outer wall and an inner circularly cylindrical wall joined at respective diametrically opposite sides to said outer wall and defining a crescent-shaped flow space in respect to said outer wall at each side which is not connected to said outer wall, a mouthpiece formed on said outer wall connecting into one of the crescent-shaped flow spaces, an inlet formed on theopposite outer wall connecting into the other crescentshaped flow space, a filter mounted within said inner wall, a cover arranged on each end of said filter and defining a flow space on the inlet which flows from said crescent-shaped space over said cylindrical wall to one end of said filter and from the opposite end of said filter over said cylindrical wall to said mouthpiece.

10. A respirator, according to claim 9, wherein said flow spaces on each end of said filter are of wedgeshaped configuration and said flow space from said inlet to said filter gradually narrows toward said filter, said flow space from the opposite end of said filter to said mouthpiece gradually widens.

Claims

1. A respirator comprising a housing having a flat cylindrical filter receiving wall defining a space therein for a filter, a filter within said receiving wall space, a mouthpiece in said housing adjacent to and exterior of one end of said filter receiving wall, an air inlet defined in said housing adjacent to and exterior of the diametrically opposite side of said filter receiving wall, and cover means overlying each side of said space and spaced from said filter receiving wall and defining a flow space from said inlet on one end of said filter with gradually narrowing flow space and a flow space on the opposite end of said filter with gradually widening flow space area to said mouthpiece.

3. A respirator, according to claim 1, including a nose clamp connected to said mouthpiece and being insertable therein.

9. A respirator, comprising a housing having an oval-shaped outer wall and an inner circularly cylindrical wall joined at respective diametrically opposite sides to said outer wall and defining a crescent-shaped flow space in respect to said outer wall at each side which is not connected to said outer wall, a mouthpiece formed on said outer wall connecting into one of the crescent-shaped flow spaces, an inlet formed on the opposite outer wall connecting into the other crescent-shaped flow space, a filter mounted within said inner wall, a cover arranged on each end of said filter and defining a flow space on the inlet which flows from said crescent-shaped space over said cylindrical wall to one end of said filter and from the opposite end of said filter over said cylindrical wall to said mouthpiece.

10. A respirator, according to claim 9, wherein said flow spaces on each end of said filter are of wedge-shaped configuration and said flow space from said inlet to said filter gradually narrows toward said filter, said flow space from the oppoSite end of said filter to said mouthpiece gradually widens.