US 2708932 A
Description (OCR text may contain errors)
May 24, 1955 PH 2,708,932
RESPIRATOR Filed Aug. 3, 1951 INVENTOR.
United States Patent RESPIRATOR George]. Pipher, Reading, Pa., assignor to Willson Products, Inc., Reading, Pa., a corporation of Pennsylvania The present invention relates to a respirator, and more particularly to a strainer or filter bag for a respirator to protect the wearer against dust and other harmful inhalations. This invention constitutes an improvement over the respirator construction shown in United States Patent Number 1,837,591 to H. F. Shindel dated December 22, 1931, assigned to the present assignee.
An outstanding disadvantage of presently used respirator bags, such as the one disclosed in the above mentioned patent, is that they are generally made up of several pieces and, more specifically, as shown in the above patent, three pieces which must be carefully shaped individually and then sewn together along substantial lengths of seams. These long seams not only detract from the efliciency of the respirator and the appearance but involve unnecessary expenditure of time in manufacture which appreciably increases the cost, particularly in large-scale manufacture of such respirator bags.
An object of the present invention is to provide a novel strainer or filter bag for a respirator which is devoid of the above-named disadvantages and which can be made very simply and inexpensively, also which involves a minimum of seam lengths.
Another specific object of the present invention is to provide a novel shaped blank in the form of a one-piece fabric which is so shaped that when its adjoining edges are sewn together it will form a complete filter bag for a respirator.
Other objects and advantages of the invention will become apparent from a study of the following description taken in conjunction with the accompanying drawing wherein:
Figure 1 is a plan view of a blank of filter material, such as cloth, showing the general outline or configuration before the blank is folded for the seaming operation.
Figure 2 is a plan view of the blank shown in Figure 1 wherein the stem portion is folded over the main body portion and in readiness for further bending of the body portion to bring the edges to be seamed together.
Figure 3 is a perspective view of the respirator strainer element or filter bag showing the appearance of the completed bag after the corresponding edge portions have been sewn together along the two major lengths of seams.
Figure 4 is a perspective view of a frame ring which is adapted to be mounted on the face of the wearer and to which the open or mouth end of the filter bag is adapted to be turned over and firmly secured, and
Figure 5 is a side elevational view, partly in cross section, of a complete respirator showing the mode of the attachment of the respirator bag to the frame ring and the manner that the frame ring is held against the face of the wearer.
Referring more particularly to Figure l of the drawing, numeral 1 denotes, generally, a blank of filter material, such as cloth, which is cut out to form a body portion a, somewhat of the shape of a four-leaf clover, and a stem portion b. The two upper leaf portions of the somewhat Patented May 24, 1955 'ice clover-leaf shape of the body portion a are truncated along straight lines c and dwhich together with the bottom edge e of thestem portion are adapted to form the mouth portion of the completed respirator bag. The stem portion b is curved inwardly at its lower part and outwardly at its upper part as shown, so that when the stern portion b is folded over portion a in the manner shown in Figure 2, the curved outer edges of the stem portion will correspond to the curvature of the curved parts of the body portion so that when the respective edge portions thereof are brought together and sewn along lines of scams, 1 and g such as shown in Figure 3, they will form a completed bag to serve as a strainer or filter bag. The sides of the small triangular cut-out portion at the top of body portion a are brought together and sewn along seam h.
It will be observed in Figures 3 and 5 that the strainer bag has a mouth portion of greater circumference than the adjoining neck portion and that the general shape of the bag is somewhat similar to that of a boxing glove,
that is generally rounded at the closed end and of less curvature along the side portions as viewed in Figure 3.
Figure 4 shows a frame ring of well known construction for mounting on the face of the wearer as shown in Figure 5 and onto which the mouth portion of the bag is fastened. The frame ring comprises a substantially triangular element, preferably of rubber or other flexible material, having an apex portion 2, adapted to fit around the nose of the wearer, and a widened lower portion 3 which is adapted to underlie the mouth of the wearer above the chin. The frame ring has an outwardly turned marginal edge or bead portion 4, extending throughout the entire periphery with the exception of the nose portion 2 and onto which an edge portion of the mouth of the bag is adapted to be turned over, inside out, as shown in Figure 4 so as to present the interior surface of the bag against the face of the wearer to provide a more effective air-tight seal with the face of the wearer. The interior surface of the bag is preferably more fleecy or fluffy as compared to the exterior surface so as to increase the air-tightness of the fit with the face of the wearer. The outwardly turned marginal edge portion of the mouth of the bag is firmly clamped in place by means of a wire spring or clamp 5.
The filter bag when mounted on the frame ring is mounted on the face of the wearer by means of flexible straps 6 whose forward ends are secured to opposite sides of the frame ring by snap fastener elements 7.
In order to keep the bag in its distended or expanded position, a distender spring 8 is provided which is in the shape of a helically coiled wire whose diameter at the central portion is greater than those of the end portions as shown in Figure 3 and whose extremities 8a are hooked so that they may be joined together when the spring is compressed for storing the spring in a smaller space for packing, etc.
Thus it will be seen that I have provided a novel filter bag construction for a respirator which enables the making of the filter bag from a single blank piece instead of from several blank pieces as is conventional, furthermore, I have provided a novel blank shape which is so cut out as to provide a complete bag with a minimum amount of seaming, therefore greatly increasing the el'ficiency of the bag as well as greatly enhancing the appearance and, above all, greatly saving time in the manufacture thereof and considerably reducing manufacturing costs.
While I have illustrated and described a specific embodiment of my invention, it will be understood that this is by way of illustration only, and that various changes and modifications may be made within the contemplation of my invention and within the scope of the following claim.
A respirator comprising a face-fitting, substantially triangular frame ring, a strainer bag having an inner fleecy surface and having a mouth portion turned out and detachably secured to said frame ring so that a fleecy inner wall portion thereof will engage the face of the wearer to provide an air tight seal, the front and side portions of said bag being devoid of seams extending lengthwise of the bag and being in the form of a one piece blank of filtering cloth of substantially cloverleaf shape consisting of an integral stem-like portion and a body portion substantially in the form of a four-leaf clover with the two leaf-like protuberances most removed from said stem truncated along straight lines, portions of the outer margins of which form a seam with the outer margins of said integral stem-like portion which is outwardly curved then inwardly curved in a direction toward its extremity, whereby only two major seams are provided which extend along the height of said bag and which are located at the rear of said bag.
References Cited in the file of this patent UNITED STATES PATENTS 1,184,485 Mummert May 23, 1916 1,683,678 Kitterman et al. Sept. 11, 1928 1,837,591 Shindel Dec. 22, 1931.
2,009,073 Shindel July 23, 1935 2,425,683 Martin Aug. 12, 1947 FOREIGN PATENTS 445,366 Great Britain Apr. 8, 1936