GB2214556A

GB2214556A - A panic exit device

Info

Publication number: GB2214556A
Application number: GB8801043A
Authority: GB
Inventors: Richard B Cohrs; Paul J Haeck; Gary R Jacobs
Original assignee: Von Duprin LLC
Current assignee: Von Duprin LLC
Priority date: 1988-01-18
Filing date: 1988-01-18
Publication date: 1989-09-06
Also published as: GB8801043D0

Abstract

A panic exit device is of a push pad type having a translating action rod (38) which is biased in a latch-extended position. An abutment (44) is slidably mounted to the action rod to receive there against the extending plunger (66) of a shock absorber (64) which is removably coupled to an open guide base (32). The base is mounted on a base plate (34) to support action rod operating bellcranks (36), and to support the action rod therein also. A shock absorber holder (54) is clasped to the guide base, and a cylinder (62) of the shock absorber, in which a viscous fluid is confined, is engaged by the holder to direct the plunger (66) toward the abutment. In the depicted embodiment, the plunger resists retraction, to decelerate and damp the return of the push pad and action rod to their at-rest positions and, consequently, to suppress the operating noise of the panic exit device. <IMAGE>

Description

A PANIC EXIT DEVICE This invention pertains to a door hardware known as a panic exit device (by the Door Hardware Institute) and is most common in a push pad type exit device. The push pad version of the panic exit device is known to be more attractive and modern looking, offering enhanced features over the cross bar version of the device. However, the push pad style of the device can be very noisy because of the internal impacts of the push pad in the inward and outward motions. It is an object of this invention to set forth a panic exit device designed to substantially reduce the internal impact noise of the push pad assembly.

The push pad assembly, in panic exit devices, is depressed to unlatch a door to allow access in or out of a building. The inward motion (downward) of the push pad of the assembly results in latch bolt retraction of the device. When the push pad is released, the latch bolt extends and the push pad returns to its original rest position. Prior art designs utilized rubber bumpers to reduce impact noise in both the inward and the back-torest positions of the push pad. The rubber bumper design concept has been marginally acceptable to customers in reducing impact noise, but something better has long been sought by the trade.It is therefore a further object of this invention to set forth a panic exit device having noise suppression comprising means defining a bearing surface; an action rod; means joining said rod to said bearing surface for translation of said rod in opposite axial directions to operate a latch; and means coupled to both said rod and said bearing surface for damping and shock absorbing translation of said rod.

It is a feature of the invention to utilize a hydraulictype shock absorber to cushion impact of the push pad.

Tests have indicated that the shock absorber may not be required in both the inward and return-to-rest movements.

It is understood, however, that this concept could be used in either the inward movement, the return-to-rest movement, or both movements.

The concept of the hydraulic dampener or shock absorber is to freely release fluid from one chamber to a second chamber in one direction of the push pad movement. In the other direction, fluid flow is orificed to reduce the force and speed of the return of the push pad, and its associated action rod and ancillary linkage.

Further objects of the invention, as well as the novel features thereof, will become more apparent by reference to the following description taken in conjunction with the accompanying figures, in which: Figures 1, 2, and 3 are rudimentary sketches of the essential nature of the invention as employed with the action rod of a push pad type panic exit device; Figure 4 is a detail illustration of the preferred embodiment of the invention in association with a prior art, panic exit device having an action rod; Figures 5 through 7 are enlarged illustrations of the shock absorber holder used in the Figure 4 embodiment; and Figures 8 through 10 are enlarged illustrations of the abutment component used in the Figure 4 embodiment.

As shown in Figure 1, a cylinder 10 which confines a viscous fluid 12 is fixed at one end to a rigid structure 14. A piston 16, having a projecting piston rod 18 is movable within the cylinder 10, and the rod 18 is coupled to a further linkage 20 which, in turn, is fixed to the action rod 22 of a panic exit device of the push pad type. The action rod 22 is biased, by the compression spring 24 shown, to the right-hand direction. Accordingly, when the push pad (not shown) is depressed, the action rod 22 is forced to move against the bias of the spring 24 to the left. The piston has a small orifice 26 formed therethrough and, consequently, the viscous fluid 12 within the cylinder 10 may pass therethrough and, in so doing, accommodate translation of the action rod 22.In either direction of the action rod translation, however, the movement is damped the viscous fluid 12 passes through the orifice 26 quite slowly.

The Figure 2 sketch depicts an arrangement where the damping of the translation of the action rod is effected in only one direction, substantially. However, the piston 16a has a large port 28 formed therethrough, with a flapper valve element 30 operatively mounted thereon for closure of the port 28 when the piston travels in the "A" direction. In those circumstances, the fluid must negotiate the small orifice 26 and, consequently, the joined action rod 22 is delayed and slowed in its return to its normal (i.e., right-hand positioning). In that the rod 22 and its operating push pad cannot slam back into the at-rest position, the panic exit device is markedly silenced.

The Figure 3 sketch depicts an arrangement which functions quite like that of the Figure 2 device, however, the flapper valve 30a itself has the metering orifice 26a therein; by this expediency, the piston 16b requires only one broaching.

In Figures 4 through 10, is depicted a best-known embodiment of the invention as incorporated in a prior art type of panic exit device of the push pad style. Open guide bases 32 (only one is shown) are fixed to a base plate 34, and journal therein right-angular bellcranks 36 which, in turn, are coupled to a push pad (not shown, which causes the bellcranks to pivot on their pivot pins) and to a translating action rod 38. The latter is linked to a latch (not shown), in the manner well known to those of ordinary skill in the art to which the invention pertains. The compression spring 40, reacts from the limit stop pin 42 to urge the action rod 38 to the right (as viewed in Figure 4). The broken line depictions in Figure 4 show the dispositions of elements in the relaxed, or latch-extended positioning of the panic exit device.The full-line illustrations depict the attitudes of the same components when the device is "pushed" to retract the latch.

An abutment element 44, the same having a sleeve 46, in which to confine the one end of the spring 40, and an upstanding abutment 48, is slidably engaged with the action rod 38. The sleeve 46 has a large, inside diameter, in which to nest the spring 40 and rod 38, and an integral, smaller, inside diameter in which to confine only the rod. The latter portion of the sleeve 46 has a pair of slots 50 in which to receive the limit-stop pin 42 for the spring 40.

The open guide bases 32 have rectangular openings 52 formed in the side walls thereof, the same serving as sockets in which to latch a shock absorber holder 54.

The holder 54 has a pair of resilient limbs 56 with tapered latches 58 which snap into the openings 52 to fix a pair of arcuate jaws 60 in extension from the guide base 32. The jaws 60 resiliently and removably receive therein the cylinder 62 of a viscous-fluid shock absorber 64. The plunger 66 of the absorber 64 (which absorber, by the way, is available from ACE Controls, Inc., P. O.

Box 71, Farmington, Michigan 48024) is urged against the upstanding abutment 48. In this embodiment, the plunger 66 resists retraction, and causes a hydraulic deceleration, due to the viscous fluid confined in the cylinder 62, of the action rod 38 as it moves from the latch-open position to the return to rest position (with the latch extended/closed).

Claims

CLAIMS:

1. A panic exit device having noise suppression, comprising: means defining a bearing surface; an action rod; means joining said rod to said bearing surface for translation of said rod in opposite axial directions to operate a latch; and means coupled to both said rod and said bearing surface for damping and shock absorbing translation of said rod.

2. A panic exit device, according to claim 1, wherein: said coupled means comprises (a) a rod-support element mounted to said bearing surface, (b) an abutment coupled to said rod, and (c) means for yieldably resisting movement of said rod in at least one of said axial directions, interpositioned between said element and said abutment.

3. A panic exit device, according to claim 2, wherein: said movement-resisting means comprises a shock absorber.

4. A panic exit device, according to claim 3, wherein: said shock absorber is of the viscous-fluid type.

5. A panic exit device, according to claim 3, wherein: said element and said abutment comprise first and second means, respectively, for cooperatively supporting and functionally engaging said shock absorber; said absorber comprises a viscous-fluid-confining cylinder, and a translating plunger extending from said cylinder; said cylinder is mounted to one of said first and second means; and said plunger is biasingly engaged with the other of said first and second means.

6. A panic exit device, according to claim 5, wherein: said element has sockets formed therein; and further including a holder for said cylinder; wherein said holder has resilient limbs; and said limbs have portions thereof resiliently nested in said sockets for removably securing said holder to said element.

7. A panic exit device, according to claim 2, wherein: said abutment comprises (a) a sleeve for slidably receiving said action rod therein; and (b) an arm coupled to, and projecting outwardly from, said sleeve.

8. A method of suppressing noise in a panic exit device which has (a) means defining a bearing surface, (b) an action rod, and (c) means joining said rod to said bearing surface for translation of said rod in opposite axial directions to operate a latch comprising the steps of: dampening and shock absorbing translation of said rod by (a) coupling shock absorber means to said rod, and (b) also coupling said shock absorber means to said bearing surface.

9. A method, according to claim 8, wherein: said coupling steps comprise (a) mounting a rod-support element to said bearing surface, (b) coupling an abutment to said rod, and (c) interpositioning a viscous-fluid-type shock absorber between said element and said abutment.

10. A method, according to claim 9, wherein: said interpositioning step comprises coupling a shock absorber holder to said element.

11. A method, according to claim 10, wherein: said mounting step comprises securing to said bearing surface a rod-support element which has a pair of parallel, side walls with apertures formed therein; and said interpositioning step further comprises (a) providing such an aforesaid holder which has a pair of resilient limbs, and (b) resiliently nesting portions of said limbs in said apertures.

12. A panic exit device, substantially as hereinbefore described > ith reference to the accompaning drawings.

13. A method of suppressing noise in a panic exit device, substantially as hereinbefore described with reference to the accompanying drawings.