US2913757A

US2913757A - Pneumatic door closer device

Info

Publication number: US2913757A
Application number: US623206A
Authority: US
Inventors: Bert A Quinn
Original assignee: Individual
Current assignee: Individual
Priority date: 1956-11-19
Filing date: 1956-11-19
Publication date: 1959-11-24
Anticipated expiration: 1976-11-24

Description

Nov. 24, 1959 B. A. QUINN PNEUMATIC DOOR CLOSER DEVICE Filed Nov. 19. 1956 I N VEN TOR.

Arme/V56 Ullid, Staf-CS Patent O "ice,

p a fz91s,7`57 l .f i PNMAIOOR CLOSER DEVICE l 'iir't Alquimi; sf. Paul, Minn. V Appiictiun November 19, 1956, serial No. 623,206 '(cl. 16-66) i Myinvention relates to improvements in pneumatic door closing devices and is in the nature of a modification of the structure dislosedand broadly claimed inmy copending application, Pneumatic Door Closer Device, S. N. 623,109, filed of even date herewith.

As pointed out in my copending application above identified, when conventional spring actuated pneumatic piston and cylinder door closing devices are used in connection with light weight doors such as aluminum door's, the swing of the door is Vso rapid that bouncing or rebounding invariably resultsduring the iinal closing movements of the door due to rapid compression of the air within the cylinder. a

The primary object of my invention is the provision of a device of the class above described which is provided not only with means for limiting the bouncing or rebounding action of the door during its linal closing movements vbut which. is also provided with meansf for partially offsetting the force progressively exerted by the coil compression spring within the cylinder, during iinal opening movements of the door.

A further object of my invention is the provision of means, whereby the decreasing yielding bias of the coil spring during final door closing movements, is supplemented. r

A still further object of my invention is the provision of means whereby the increasingly greater yielding bias exerted upon the door by the coil compression spring during opening movements thereof, is partially offset during final door opening movements.

A still further object of my invention is the provision of a novel arrangement of parts whereby yielding means interposed between the door and the door closing piston cylinder (and working at substantially right angles to the coil spring within the piston) creates constant but variable friction between the connecting rod and the end of the cylinder in which it is slidably mounted, whereby to eifect steadying movements to the door throughout its entire range of closing movements.

A further object of my invention is the provision of a device in the form of an attachment for conventional pneumatic cylinder and piston door closing devices which will eliminate bouncing or rebounding of the door during final closing movements thereof, and which will also partially offset the force of the coil compression spring within the cylinder during' nal opening movements of the door.

A further object of my invention is the provision of a device of the class immediately above described, which is relatively inexpensive to produce, which has a minimum of working parts, which is rugged and durable in construction, and which is foolproof in its operation.

The above and still further objects of my invention will become apparent from the following detailed specification, appended claims and attached drawing.

Referring to the drawing, wherein like characters of reference indicate like parts throughout several views:

p 2,913,757 Baier-.fed Nov. 24, '195s 2 Fig. 1 is avview in transverse section of a conventional frame and cooperating hinged door, showing my novel device in top plan,

Fig. 2 is an enlarged fragmentary sectional view as seen substantially from the line 2-2 of Fig. 1, and

Fig. 3 is an enlarged sectional view as seen substantially from the line 3--3 of Fig. 1.-

Referring with greaterparticularity to the drawing, the numerall ,indicates in its entirety a door frame to which a door 2 is hingedly secured, as at 3.

v The "spring-operated pneumatically-controlled door closer, herein broadly referred to as an extensible and retractable device includes an elongated tubular cylinder 4, a connecting rod 5, a piston or plunger 6 mounted fast on the inner end of the plunger rod 5 within the cylinder 4and a coil compression spring 7 which is compressed between the piston 6 and the innerend 8 of the cylinder ,4. It will be noted that the plunger rod 5 projects through and is slidably mounted for extending and retracting movements in end 8 of the cylinder 4.

The construction of the' cylinder 4, the piston 6 and immediately associated parts, including suitable means for ,controlling the escape of air from the end 9 of the cylinder 4 during retracting movements of the connecting rod 5, form no`part of the instant invention and hence will` not be explained in detail. It sulces to state that a 'Patent 2,646,589 dated July 28, 1953.

suitablev arrangement of such parts is disclosed in my As shown, the projectedend of the connecting rod 5 1s pivotally secured to a suitable bracket 10, as. indicated at 1-1. Bracket 10 in turn is secured to the door framev 1 in laterally `inwardly spaced relationship't thedoor.2, with the axis of the pivotal connection 11 in parallel relationship to the axis of swinging movement of the hinge means 3. The outer end 9 of the cylinder 4 is pivotally secured as at 12 to a suitable bracket 13 detachably securable to the door 2 by any suitable means such as screws 14. The axis of pivotal connection 12 is parallel to the axis of pivotal connection 11.

A coil tension spring 15 is shown as encompassing the cylinder 4, intermediate the ends 8 and 9 thereof and preferably in relatively closely spaced relationship to .the inner end 8. The hooked opposite ends 16 of the coil spring 15 pass through apertured ears 17 carried by a mounting plate 18 preferably adapted to be detachably secured to the door 2. As shown particularly in Fig. 3, the unnumbered circumferentia'lly extended axially spaced flanges form a nest for the coil spring 15 and positively preclude axial movements of the spring 15 with respect to the cylinder 4.

By this novel arrangement above described, one effectively has a primary spring means, namely the coil compression spring 7 which exerts a yielding bias on the cylinder 4 and cooperating connecting rod equipped piston 6 generally longitudinally thereof to impart retracting- (door closing) movements thereto, and a secondary spring means, namely the coil tension spring 15, which exerts a yielding bias on the cylinder 4 and connecting rod equipped piston 6 carried thereby at right angles to the longitudinal dimensions thereof in the direction of the door 2. Up to a given point, the primary spring 7 and the secondary spring 15 both exert an independent yielding bias upon the door 2 to move same toward the closed full line position of Fig. l upon the hinges 3, the coil spring 7 exerting a progressively greater bias as-the door 2 approaches its maximum opened position.

This point is reached at dead center with respect to

connections

3, 11 and 12. Beyond this dead center position, the action of the coil tension spring 15 is reversed and consequently, through

connections

3, 11 and 12, said spring 15 exerts a yielding bias on the door 2 in a direction opposite to that exerted by the coil spring 7, namely i in a direction to impart opening movements to theqdoor 2. This yielding bias offsets to a degree the progressively increasing bias of the coil spring 7 to impart closing movements to the door 2. Thus, when the door 2 is released at this point, its initial closing movements are notgob` jectionably rigid and violent (as is customary in devices 'of this character) but rather are slow and gentle.

Furthermore, if the door 2 approaches the full line closed position of Fig. 1, the bias exerted by the coil spring 7 becomes progressively less. At'this point, the coil tension spring 15 acts as a booster to totally overcome the rebounding or bouncing action of the door 2, above described.

Another feature of importance is as follows: The coil tension spring 15, working at substantially right angles to the conventional coil compression spring 7 within the cylinder 4, creates constant but variable friction between the connecting rod and the end 8 of the cylinder 4 in which it is slidably mounted. This is clearly illustrated in Fig. l of the drawing. As shown by the intermediate relatively long broken line showing, the friction between the connecting rod 5 and the end 8 of the cylinder 4 is greatest at this intermediate position of the door 2 because of the greater angularity between the cylinder 4 and the door 2. This angularity becomes less as the door 2 approaches either the extreme open (illustrated by relatively small broken lines) position or the closed posi'- tion shown by full lines. This frictional engagement imparts steadying movements to the door 2 during its entire closing movements, and is also a factor in the eliminating of the bouncing or rebounding action of the door 2 as it approaches its closed position.

My invention has been thoroughly tested and found to be completely satisfactory for the accomplishment of the above objects and while I have disclosed a preferred embodiment thereof, it should be specifically understood that same is capable of considerable modification without departure from the scope and spirit of the appended claims.

What I claim is:

l. A pneumatic door closer comprising a cylinder element and a piston-equipped plunger element mounted for extending and retracting movements relative to said cylinder element, meansy for pivotally connecting one end of one of said elements to adoory frame oiy an axis parallel to the axis of swinging movements of a cooperating door in said frame, means' for pivotally connecting the opposite end'of the other of said elements to said door on an axis parallel to said first-mentioned axis, means within saidV cylinder element yieldingly biasing said plunger element in a retracting direction relative to said cylinder element, and independent yielding means carried by one of said elements intermediate said pivotal connections, said independent yielding means exerting a yielding bias 'at substantially right angles to the direction of the bias of said first-mentioned yielding means in the direction of said door, said independent yielding means comprising a tension spring connected to an intermediate portion of said cylinder and having at least one end thereof connected to the door.

2. The structure defined in claim 1 in which said tension spring is a coil spring encompassing said cylinder, and in further combination with means on said cylinder anchoring said coil spring against movement longitudinally thereof.

Perregrine .Tune 1l, 1901 Bowles Feb. 28, 1922