US3621868A

US3621868A - Breathing-tube check valve

Info

Publication number: US3621868A
Authority: US
Inventors: Layton A Wise
Original assignee: Mine Safety Appliances Co
Current assignee: MSA Safety Inc
Priority date: 1969-04-29
Filing date: 1970-09-14
Publication date: 1971-11-23
Anticipated expiration: 1988-11-23

Abstract

A breathing tube has a pair of circumferentially spaced parallel rib-receiving grooves in each end, with the grooves in one end a different distance apart than those in the other end. A valve body is provided in the form of a cup with a base surrounded by a sidewall adapted to fit in either end of the tube. The base has an opening through it surrounded at each end by a valve seat. A valve closure can be secured to the base for engagement with either seat. The outer surface of the cup sidewall has three parallel ribs parallel to the cup axis and spaced different distances apart. One rib is removable to permit the cup to be inserted in one end of the tube, and another rib is removable to permit the cup to be inserted in the other end of the tube.

Description

United States Patent Inventor Layton A. Wise Washington, Pa.

Appl. No. 71,802

Filed Sept. 14, 1970 Patented Nov. 23, 1971 Assignee Mine Safety Appliances Company Pittsburgh, Pa.

Original application Apr. 29, 1969, Ser. No. 820,070, now Patent No. 3,572,332. Divided and this application Sept. 14, 1970, Ser. No. 71,802

BREATHING-TUBE CHECK VALVE 2 Claims, 6 Drawing Figs.

U.S. Cl 137/315, 29/156.7 R, 29/l57.1 R,'137/454.2, l37/454.4, 137/515, 137/525.3

Int. Cl F16k 51/00 Field of Search 29/1 56.7 R, 157.1 R; 137/315, 454.2, 454.4, 515, 515.3,

Primary Examiner- Laverne D. Geiger Assistant Examiner- David J. Zobkiw Attorney-Brown, Murray, Flick & Peckham ABSTRACT: A breathing tube has a pair of circumferentially spaced parallel rib-receiving grooves in each end, with the grooves in one end a different distance apart than those in the other end. A valve body is provided in the form ofa cup with a base surrounded by a sidewall adapted to fit in either end of the tube. The base has an opening through it surrounded at each end by a valve seat. A valve closure can be secured to the base for engagement with either seat. The outer surface of the cup sidewall has three parallel ribs parallel to the cup axis and spaced different distances apart. One rib is removable to permit the cup to be inserted in one end of the tube, and another rib is removable to permit the cup to be inserted in the other end ofthe tube.

Pmmmm. V 3,621,868

' sumaur'a ATTORNEYS.

mvENTbR. AAYTO/V A. M5:

BREATHINGTUBE CHECK VALVE This application is a division of my copending Pat. AAAOapplication, Ser. No. 820,070, filed Apr. 29, 1969 now US. Pat. No. 3,572,332.

It is among the objects of this invention to provide a check valve which has a body that can be used for either an inhalation or an exhalation valve, and which is so formed that inhalation and exhalation valves cannot be confused in mounting them in the breathing tube.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in which AAAO FIG. I is a fragmentary front view, partly in section, of breathing apparatus; AAAO FIG. 2 is a fragmentary side view, partly in section;

FIGS. 3 and 4 are enlarged longitudinal sections taken in the lines IlIlII and IV-IV, respectively of FIG. 2; AAA

FIG. 5 is an enlarged side view of the combination unit; and

FIG. 6 is a diagram illustrating the versatility of the check valve body.

Referring to FIGS. 1 AAAOand 2 of the drawings, a breathing mask 1 of more or less conventional form is provided inside with a nose cup 2 to fit snugly around the nose and mouth. The lower portion of the mask is provided with an inlet opening encircled by a forwardly and downwardly extending flexible flange 3. This opening registers with an outlet opening 4 in the lower part of the nose cup. Extending rearwardly away from the opposite AAAOsides of the flanged inlet opening are inlet ducts 6 that open into the mask. The nose cup is provided with inlets normally closed by check valves 7. Air enters the mask through ducts 6 and then enters the nose cup through the check valves. Exhaled air leaves through the nose cup outlet 4 and the flanged opening of the AAAdmask.

A combination valve and speaking diaphragm unit is attached to the mask at its flanged inlet opening to direct air into and out of the proper channels in the mask. This unit includes a breathing tube in the form of a tubular member 10 that extends across the front of the mask and that is provided centrally with front and back openings. Projecting from the back of this member around the back opening 11 is a rigid flange 12 that is inserted in the mask inlet, as shown in FIGS. 2 and 3, where it is gripped by the mask AAAOflange 3. A clamp 13 may encircle the latter in order to hold the two flanges tightly together. This clamp is in front of the mask inlet ducts 6, and the portion of flange l2 behind the duct inlets is proAAAOvided with lateral openings 14 (FIGS. 3 and 5) registering with those inlets. AAAO Mounted in the front opening of tubular member 10 is a speaking diaphragm 16 as shown in FIG. 3. The front AAAOend of a rigid exhalation tube 17 is joined to the tubular member around the diaphragm. This tube extends rearwardly out of the back opening 11 of the tubular member and projects from the rear end of flange 12 The rear end of the tube is shaped to be inserted in nose cup outlet 4 and to be sealed therein. Consequently the nose cup outlet is in direct communication with the tube and with the speaking diaphragm at its front end. At least the major portion of the tube is spaced inwardly from the encircling flange l2 and the wall of back opening 11 in order to provide a space between them. Preferably, the tube is concentric with the back opening as shown in FIG. 4. The rear end of the space between the exhalation tube and the encircling flange is closed by a back wall 18. The portion of the exhalation tube inside tubular member 10 is provided witAAAOh a lateral outlet opening 19 that is surrounded by a short flange 20 which connects the opening with one end of the tubular member and helps support the tube in that member.

It will be seen that with this arrangement there is a passage from one end of the tubular member into the space around the exhalation tube and then out through openings 14 and into the inlet ducts 6 of the mask. Another passage extends from the nose cup through the exhalation tube and out through its outlet l9 and the other end of the tubular member. In order to direct air in the proper paths through this unit a check valve is mounted in each end of tubular member 10. The valve 22 in the end of that member which communicates with the inside of the exhalation tube is an exhalation valve, while the other valve 23 is an inhalation valve. The result is that the two valves and the speaking diaphragm are carried by the short tubular member which is inserted in the front of the mask. Only the central portion of the AAAxtubular member is enlarged. AAAO In accordance with this invention, the bodies are made from cups which initially are identical and interchangeable. They can be inserted in the ends of the tubular member. As shown in FIGS. 3, 4 and 5, each cup has a cylindrical sidewall 25 and a base 26 perpendicular to the axis of the cup. The opposite end of the cup is encircled by a flange 27 that limits the distance the valve can be inserted in the tubular meAAAOmber. The base of the cup is provided with an opening 28 for passage of air and with

valve seats

29 and 30 at opposite ends of the opening. The opening has a flat side, between which and the adjacent side of the cup the base is provided with one or more openings 31 (FIG. 4) through it that receive h'eaded pins 32 holding a flexible valve flap 33 against one or the other of the valve seats, depending upon whether the flap is inside or outside the cup. Thus, with the same cup, a flap can be placed against either valve seat. Normally, the pins would be cemented in the holes in the cup base. If the flap is inside the cup, the valve is AAAOthe exhalation valve, while if the flap is outside, the inhalation valve is formed.

In order to avoid inserting the valves in the wrong ends of the tubular member, the outside of each cup is provided with a plurality of parallel ribs extending parallel to the axis of the cup. To be able to use cups for either valve, there should be three ribs originally. As illustrated in FIG. 6, one rib 35 is spaced a greater distance from the center rib 36 than is the other rib 37. On all cups, the ribs are in the same positions relative to one another. The inside of one end of tubular member 10 is provided with a pair of parallel grooves spaced apart the same distance as only two of the ribs on a valve cup, while the inside of the other end of the tubular member is provided with two parallel grooves spaced the same distance apart as the third rib is spaced from one of the other ribs. When an exhalation valve is made, the rib is removed that would not fit in either of the two grooves in the exhalation end of the tubular member. A different rib has to be removed from the inhalation valve in order for the two remaining ribs to fit in AAA%the grooves in the inlet end of the tubular member. This prevents the valves from being inserted in the wrong ends of that member. For example, rib 37 can be removed from the inhalation valve, and rib 35 removAAAbed from the exhalation valve.

By requiring only one form of valve body for both types of valves, their cost can be reduced because only one mold is needed. The valve flap can be placed against either seat with equal ease. It takes only a moment to remove the appropriate rib from the outside of the valve cup.

I claim:

1. A check valve for use in a breathing tube having a pair of circumferentially spaced parallel rib-receiving grooves in each end with the grooves in one end a different distance apart than AAAOthose in the other end, the valve comprising a cup provided with a base surrounded by a sidewall adapted to fit in either end of the tube, said base being provided with an opening, a valve closure, and means for securing said closure to the base at either end of the opening for engagement with the adjoining seat, the outer surface of said sidewall being provided with three parallel ribs extending parallel to the cup AAAOaxis and spaced different distances apart, one of said ribs being removable to permit the cup to be inserted in one end of the tube with the other two ribs in the adjoining grooves, and a different rib being removable to permit the cup to be inserted in the other end of the tube with the other two ribs in the LAAABgrooves at that end.

2. A valve according to claim 1, in which said valve closure is a flexible flap, and said closure-securing means includes a pin extending through said flap at one side of said base opening and a pin-receiving hole through the base at one side of said opening, the pin being insertable from either end of the hole so AAAOthat the flap can be placed against either valve seat, depending upon which of said ribs is removed. 5

* i l II

Claims

1. A check valve for use in a breathing tube having a pair of circumferentially spaced parallel rib-receiving grooves in each end with the grooves in one end a different distance apart than those in the other end, the valve comprising a cup provided with a base surrounded by a sidewall adapted to fit in either end of the tube, said base being provided with an opening, a valve closure, and means for securing said closure to the base at either end of the opening for engagement with the adjoining seat, the outer surface of said sidewall being provided with three parallel ribs extending parallel to the cup axis and spaced different distances apart, one of said ribs being removable to permit the cup to be inserted in one end of the tube with the other two ribs in the adjoining grooves, and a different rib being removable to permit the cup to be inserted in the other end of the tube with the other two ribs in the grooves at that end.

2. A valve according to claim 1, in which said valve closure is a flexible flap, and said closure-securing means includes a pin extending through said flap at one side of said base opening and a pin-receiving hole through the base at one side of said opening, the pin being insertable from either end of the hole so that the flap can be placed against either valve seat, depending upon which of said ribs is removed.