US 2721597 A
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Description (OCR text may contain errors)
Oct. 25, 1955 F. PITRELLA DOOR KNOB CUSHION COVER Filed Dec. 24, 1954 INVENTOR. FRANK PIT RELLA HIS ATTORNEY United States Pu 2,721,597 DooRKNoBcU'sHIo'N COVER "Frank Pitrella, *Ro'chest'er, N. Y. Application December 24, 1 9 54, Serial No. 477,525
"4Claims. (Cristi-s2 This invention-relates toa cushion cover for a convex surface door knob and' has for its purposeto provide a door knob cover of resilient elastic material that can be slipped over-a conventional door knob and will fit securely-thereon, at the same time affording cushioning meansenabling-the door knob to function as a stop', while the cushioning means efliectively prevents injury to a wall or other surface against which the door knob strikes, the impact-or shock being absorbed by cushioning means within 'the door knob cover.
It iscommonpractice to provide a rubber cover for a doorfknobyvarious devices 'having been proposed 'to provide a doorknob with some kind of cushioning means, a ri d it-is an additional purpose'to afford an elastic resilient cover that is applicable to a door knob having 'a convex outer surface, and is provided with effective cushioning means whereby there is sufficient resilience and cushioning action to adequately protect a wall or surface-against which the knob strikes and to absorb the shock or impact so as to prevent undesirable jar, while -at 'the same time affording a quickly attachable or removable elastic cover that fits over a door knob, conforming generally to the convex outer surface thereof, aridwhi'ch gives indefinite wear and a firm grip on the knob. 7
It has heretofore'been proposedto provide a door knob witha rubber cover to prevent slippage, also to provide so'mekind of cushioning'means, and it is a further objective of the invention to afford a cover that will con- "forrnto the convex outer surface of a door knob and 'also afford an air chamber arrangedin such relation to "theknob and to bendable resilient inwardly projecting portions in contact with the knob that when pressure is applied to the outer portion of the cover as when the knob strikes a wall, the air chamber permits movement of the "outer central portion of the cover toward the convex outer surface of the knob and the impact is absorbed by the "war'dly projecting bendable or compressible resilient lpor'tions such as a flange or spaced inward extensions, thatare bent or squeezed laterally when pressure is applied, and combine with the air chamber to afford a "gradual absorbing action that provides the desirable cushioning effect while maintaining the normal and'proper shape of the cover without affecting its wearing qualities.
The invention has for an additional purpose to afford 'a structure that can be economically manufactured and molded from rubber, plastic, or other suitable elastic "resilient material, and which can'be produced in various colors to carry out any desired ornamental effect.
Another object of the invention is to afford a quickly attachable door knob cover which can be successfully "employed as'a door stop and will take the place of the "mere costly metal stops now generally in use, and at the same tirrie will effectively prevent the noise and damage that'otherwise results from a door knob contacting a wall "or: other support when the door is'swung to open position.
"To these and other ends, the invention consistsin the construction and arrangement of parts that will appear 2,721,597 Patented Oct. 25, 1-955 '2 clearly from the following description when read in con- L junction 'with the'accompanying drawing, the novel features being pointed out in the claims following the specification.
In the drawings: p K
Fig. 1 is a view in side elevation of a door with a knob on both sides thereof having a convex outer surface and showing apreferred embodiment of the invention applied to both knobs, the'cover on the'right hand side appearing in side elevation and the cover on the left hand side appearing in section; p N Fig. 2 is a perspective view of the cover removed from the knob; v
Fig. 3 is a sectional view of the doorknob cover shown in Fig. 1 removed from the knob; H Fig. 4 is a view in section looking-from right to left of Fig. 3; e K Fig.5 is a sectional view similar to Fig. 3 of a modified form of the invention; 1 V
Fig. 6 is a view in section looking fromright to left of Fig. 5; and
Fig. 7 is a sectional view of a further modification.
The invention disclosed in this application is animprovement on the structure forming the subject matter of my copen ding application Serial No. 364,846, filed June 29, 1953, in which the cushioning action was obtained 5 by resilient padding forming part of the door knob cover or interposedbetween the inner surface of the cover and the outer surface of the door knob. The former structure has been found quite resistant to'a blow on the outer surface of the cover-and to possess insufficient resilience or yielding, and even though such a padding is made from sponge rubber or other resilient material, it results in a mass of rubber occupying the entire area between the outer surface of the knob and the inner surface of the cover. Such an arrangement presents too hard and non-yielding a surface up'on striking'a wall, and the present invention was designed to overcome this difiiculty by providing an open area or air chamber on the'inner surface of the cover and centrally thereof, such an chamber beinglocated between the central portion of-the outer convex surface of the knob and the central portion ofthe inner concave surface of the cover and surrounded by or cooperating with one or more flanges, projections or extensions of slight cross-section extending from the inner surfaceof the coverinwardly toward the outer surface of the'knob and in engagement with the knob. These'projections or extensions are compressible, bendable and yielding when the central portion of the cover overlying the concavity is forced toward the knob upon pressure being applied, whereupon the-air chamber in the cover permits the central part of the cover "to flatten'ag'ainst theknob and the inward movement of the central portion ofthe cover is limited 'or resisted by the surrounding yieldable resilient flange or projections, which combine with the centrally arranged air chamber "in the cover toproduce a yielding action that cushions the shock when the door knob strikes a wall, with the p'ro'per'balance between yielding 'of the central portion of the cover and resistance to such yielding, so as to ab- -'sorb the shock in the most eifective manner and at the same time prevent wear or fracture of the cover and maintain it indefinitely in its proper and normal relation to the door-knob.
The invention can be applied in various ways and in its preferred embodiment as illustrated in Figs. 1 to 4 inclusive, consists of a cover molded from rubber, plastic, or other suitable resilient elastic material enabling it to be slipped over a door knob having a convex outer surface as indicated at 1. The cover includes a relatively thin 'si'de'wall 2 and terminates at its inner portion in an opening 3 'of less diameter than the maximum diameter of the knob so that when the cover is forced over the knob, it occupies the position shown in Fig. 1, hugging closely the inner portion 4 of the knob and the sides 5 as shown.
The cover is of gradually increasing thickness from its side wall 2 toward its outer portion, affording an outer surface 6 of greater convexity than the outer surface 1 of the door knob, and an inner surface that is concaved and conforms generally to the outer surface of the door knob. The cover is provided on its inner surface and centrally between its sides with a concavity 7 affording an air pocket 8, and the outermost portion of the cover as indicated at 9 is of somewhat less thickness than the portions surrounding the concavity 7. The concavity 7 terminates in a surrounding flange 11 affording a narrow inwardly extending projection or extension of slight thickness, that is bendable, yielding and compressible as the central portion of the cover is forced toward the convex outer surface of the knob. The flange 11 prevents fracture or excessive wear of the cover while at the same time affording the required cushioning effect and most effective resilience as pressure is applied to the cover.
The cover is thickest between the flange 11 and the outer surface of the cover, and reduces gradually in thickness toward the outermost portion 9 and toward the side wall 2, affording slight pockets or air chambers 12 between the flange 11 and the side wall 2 of the cover. With this arrangement, the flange 11 is in contact with the outer convex surface of the door knob, and when pressure is applied to the outer convex surface of the cover as when the knob strikes a wall, the central portion 9 of the cover is forced inwardly toward the knob and at the same time the flange 11 is compressed and bent out wardly somewhat toward the side of the cover, the pockets 8 and 12 being reduced until substantially the entire inner surface of the cover is in contact with the outer surface of the knob.
In this fashion, the shock of the knob striking a hard surface is absorbed effectively but gradually by the combined action of the cushioning air pocket and the resilient bendable projection that is normally in contact with the knob and is compressed and bent as pressure is applied to the cover. The flange 11 also acts to restore the central portion 9 of the cover to its normal position after pressure is released and to prevent fracture or collapse of the relatively thin central portion 9 of the cover, so that the cover is always maintained in proper relationship as illustrated in Fig. 1, and possesses indefinite wearing qualities.
In the modification shown in Figs. 5 and 6, the cover is provided with an outer wall 13 that is thicker than the side wall 14 and is of gradually increasing thickness from I the side wall to the outermost portion of the wall 13. The inner surface 15 of the cover is of generally concave shape to conform generally to the convex outer surface of the knob and is normally in slightly spaced relation to said outer convex surface of the knob while 16 designates a plurality of inwardly extending projections or fingers of slight cross-section arranged in spaced relation to each other as shown in Fig. 6, and occupying a position such as to contact the outer convex surface of the knob when in normal relation. When in such position, the areas between the fingers 16 afford a multiplicity of air pockets between the inner surface of the cover and the outer surface of the knob, and when pressure is applied to the cover, the fingers 16 are compressed or bent to permit the inner surface of the cover to approach and contact more closely the convex outer surface of the knob.
The inwardly extending fingers 16 are preferably arranged as illustrated in Fig. 6, afford a greater air cushion at the center of the outermost portion of the cover and a gradually reducing air cushion toward the sides thereof. The center fingers may be omitted entirely, or the remaining fingers otherwise disposed to give the desired air cushioning effect and resiliency to the cover while at the same time interposing such resistance to the inward flex- 4 ing of the cover as to cushion properly and absorb the shock.
The fingers 16 are preferably about /1" apart, approximately W in length measured from the innermost surface of the cover to the tip of the finger, and preferably approximately A, thick at their tip portions.
The thickness and height of flange 11 in the form illustrated in Figs. 1 to 4 is approximately the same as the fingers 16 and the diameter of the concavity surrounded by the flange 11 is approximately 1", while the thickness of the cover at the point of the flange 11 is approximately one-fourth of an inch as compared with a thickness of the side wall of the cover of approximately one-sixteenth of an inch and a thickness at the outermost portion of the cover as indicated at 9 of approximately 7 in the modification illustrated in Fig. 7, the cover is provided on its inner surface at its outer portion with a resilient body of compressible material such as sponge rubber or the like as indicated at 17, which may be molded integrally with the cover 18 or formed as a separate element which is cemented or otherwise attached to the inner surface of the cover, or may be arranged loosely between the outer convex surface of the knob and the inner concave surface of the cover. The resilient compressible cushioning element 17 is provided with an inner concave surface 19 that conforms generally to and engages the outer convex surface of the knob while 21 designates a concavity formed in the inner concave surface of the resilient element 17 centrally of its periphery, affording an air chamber or pocket 22, and an inwardly projecting angular portion 23 surrounding the concavity 21 and affording a part that is compressible and bendable against the outer convex surface of the knob as the cover is forced inwardly upon pressure being applied.
As this action takes place, the outer portion of the cover and of resilient body 17 is forced inwardly toward the knob, and the projecting portion 23 surrounding concavity 22 is compressed and flattened against the knob, permitting the outer portion of the cover to move toward or in contact with the outer surface of the knob as permitted by the air pocket 22, while the angular projecting portion 23 and surrounding thickened portions of the cover and resilient element 17 act to restore the cover to its normal position when pressure is released.
While the invention has been described in relation to the particular forms of construction herein shown, it is not restricted to the details disclosed and this application is intended to cover such other modifications or departures as may come within the purposes of the improvement and the scope of the following claims.
1. A cushion cover for a convex surface door knob, comprising a resilient elastic casing surrounding the knob and having an opening at its inner portion of less diameter than the maximum diameter of the knob, and cushioning means on the interior surface of the outer portion of said casing, said cushioning means having a central concave portion overlying a considerable area of the convex outer surface of the knob and normally spaced from the said convex surface, and a resilient bendable portion projecting toward and normally in contact with the outer surface of the knob, said bendable portion being flexed when pressure is applied to said central portion.
2. A cushion cover for a convex surface door knob, comprising a resilient elastic casing conforming generally in shape to and surrounding the knob and having an opening at its inner portion of less diameter than the maximum diameter of the knob, the outer portion of said casing being of greater thickness than the sides of the casing and having a central concavity on its inner surface which normally spaces the outer portion of the casing from the knob, and an inwardly extending resilient bendable projection of slight cross section engaging the knob.
3. A cushion cover for a convex surface door knob, comprising a resilient elastic casing conforming generally in shape to and surrounding the knob and having an opening at its inner portion of less diameter than the maximum diameter of the knob, said casing having a generally concave inner surface overlying and conforming to the outer convex surface of the knob, said concave surfacehaving a considerable central area of greater concavity that is spaced from the knob and movable toward the knob under pressure, and an adjacent resilient portion which abuts the knob and is bendable and compressible upon inward pressure against said concave area.
4. A cushion cover for a convex surface door knob, comprising a resilient elastic casing conforming generally in shape to and surrounding the knob and having an opening at its inner portion of less size than the maximum diameter of the knob, said casing being of gradually increasing thickness from its sides toward its outermost 6 portion and having a concavity disposed centrally of said outermost portion on its inner surface, and a resilient bendable inwardly projecting flange of slight cross-section surrounding said concavity and engaging said convex surface of the knob.
References Cited in the file of this patent UNITED STATES PATENTS 329,321 Leger et a1. Oct. 27, 1885 1,165,052 Williams et al Dec. 21, 1915 1,410,605 Schacht Mar. 28, 1922 1,556,966 Selig Oct. 13, 1925 1,668,716 Herdman et a1. May 8, 1928 1,710,619 Haslinger Apr. 23, 1929 2,131,067 Paden Sept. 27, 1938