Patent Application
20230265680
The present invention is directed a dampening mechanism for a touch bar exit device which limits the movement of the touch bar and dampens the sound when the touch bar is used.
The use of a touch bar assembly or push bar assembly can be noisy when in use. Most if not all manufacturers recognize the metal to metal contact of the touch bar assembly is loud/noisy. Current solutions to minimize noise is to use a rubber bumper between the metal pieces. However, the rubber bumper is not durable.
Other touch bar assemblies use a hydraulic damper. However, hydraulic dampers are expensive and can require maintenance. In addition, the hydraulic damper is not effective when the touch bar is depressed, it is only effective upon return of the touch bar.
It would, therefore, be beneficial to provide a mechanism to limit travel and dampen sound when the touch bar is depressed or extended and when the touch bar is retracted or moved back to its initial or original position. It would also be beneficial to provide a mechanism which can be used over many cycles, and which requires minimal maintenance.
An embodiment is directed to a dampening mechanism for a touch bar exit device which limits the movement of a touch bar of the touch bar exit device and dampens the sound of the touch bar. In various embodiments, the dampening mechanism has a dampening spring limits the movement of the touch bar. The dampening spring may have a high spring rate to control the movement of the touch bar. A spring block may be provided to engage the dampening spring and a return spring of the touch bar exit device.
An embodiment is directed to a touch bar exit device having a touch bar and a dampening mechanism. The dampening mechanism is configured to limit the movement of a touch bar and dampen the sound of the touch bar as the touch bar is moved. In various embodiments, the dampening mechanism has a dampening spring limits the movement of the touch bar. The dampening spring may have a high spring rate to control the movement of the touch bar. A spring block may be provided to engage the dampening spring and a return spring of the touch bar exit device.
An embodiment is directed to a touch bar exit device for use on an exit door. The touch bar exit device includes a touch bar and a link bar which moves as the touch bar is depressed. A return mechanism is mounted on the link bar. A damper mechanism is mounted on the link bar. The damper mechanism limits the travel of the link bar and the touch bar to dampen the sound of the touch bar exit device when the touch bar is depressed.
An embodiment is directed to a touch bar exit device for use on an exit door. The touch bar exit device includes a touch bar, a link bar and a back plate. The link bar moves as the touch bar is depressed The link bar is movable relative to the back plate. A return spring assembly is provided in engagement with the link bar and the back plate. A damper spring assembly is provided in engagement with the link bar and the back plate. A first spring rate of the damper spring assembly is higher than a second spring rate of the return spring assembly The damper mechanism limits the travel of the link bar and the touch bar to dampen the sound of the touch bar exit device when the touch bar is depressed.
Other features and advantages of the present invention will be apparent from the following more detailed description of the illustrative embodiment, taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the invention.
The description of illustrative embodiments according to principles of the present invention is intended to be read in connection with the accompanying drawings, which are to be considered part of the entire written description. In the description of embodiments of the invention disclosed herein, any reference to direction or orientation is merely intended for convenience of description and is not intended in any way to limit the scope of the present invention. Relative terms such as “lower,” “upper,” “horizontal,” “vertical,” “above,” “below,” “up,” “down,” “top” and “bottom” as well as derivative thereof (e.g., “horizontally,” “downwardly,” “upwardly,” etc.) should be construed to refer to the orientation as then described or as shown in the drawing under discussion. These relative terms are for convenience of description only and do not require that the apparatus be constructed or operated in a particular orientation unless explicitly indicated as such. Terms such as “attached,” “affixed,” “connected,” “coupled,” “interconnected,” and similar refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both movable or rigid attachments or relationships, unless expressly described otherwise.
Moreover, the features and benefits of the invention are illustrated by reference to the preferred embodiments. Accordingly, the invention expressly should not be limited to such embodiments illustrating some possible nonlimiting combination of features that may exist alone or in other combinations of features, the scope of the invention being defined by the claims appended hereto.
As shown in
As shown in
As shown in
The link bar mounting portions 18 are attached to the touch bar mounting portions 16 through a pivot point 19 through which pins 22 extend. Each of the touch bar scissors 14 also include a mounting base 21. The link bar mounting portions are pivotally mounted to the mount bases by mounting pins 25. The mounting based 21 have mounting openings 23 which extend therethrough.
As the touch bar mounting portions 16 are moved downward as viewed in
In the illustrative embodiment shown in
Damper spring mounting projections 30 extend from the back plate 24. The damper spring mounting projections 30 are positioned between the mounting openings 26 for the respective touch bar scissors 14. In the embodiment shown, the damper spring mounting projections 30 are planar members which extend essentially perpendicular to the back plate 24. The damper spring mounting projections 30 have ends 32 which are configured to cooperate with the damper spring assembly 58. A respective damper spring mounting projection 30 also has an end 33 which is configured to cooperate with the return spring 68. Other configurations of the damper spring mounting projections 30 may be used.
As shown in
Mounting openings 36 are provided in the link bar 34. The mounting openings 36 allow pins 27 to be inserted therethrough to attach the link bar 34 to the link bar mounting portions 18 of the touch bar scissors 14. Consequently, the link bar 34 will move as the link bar mounting portions 18 are moved.
Spring block mounting portions 38 are provided on the connecting members 37. The spring block mounting portions 38 have mounting openings 40 to receive mounting hardware 42 to secure the spring block 44 to the link bar 34.
The spring block 44 has a generally planar portion 45. When assembled the planar portion 45 extends essentially parallel to the block plate 24. Link bar mounting portion 46 with mounting openings 48 are provided on or proximate to the generally planar portion 45. The link bar mounting portion 46 and the mounting openings 48 align with the spring block mounting portions 38 and the mounting openings 40 to allow the mounting hardware 42 to secure the spring block 44 to the link bar 34.
The spring block 44 has a first damper spring engagement projection 50, a second damper spring engagement projection 52 and a return spring engagement projection 56. As shown in
The damper spring assembly 58 has a damper spring 60 with spring block engagement members 62. The spring block engagement members 62 are provided at a first damper spring engagement end 64 and an oppositely facing second damper spring engagement end 66.
As shown in
The damper spring 60 has a relatively high spring rate as compared to the return spring 68. In an illustrative embodiment the spring rate of the damper spring 60 is between approximately 210 Ibf/in and approximately 250 Ibf/in, and more particularly approximately 230 lbf/in. However, other spring rates can be used. The damper spring 60 can be selected based on the spring rate, thereby allowing the push pad assembly 10 to be tuned for a particular application.
As shown in
The return spring 68 has a relatively low spring rate as compared to the damper spring 60. In an illustrative embodiment the spring rate of the return spring 68 is between approximately 6 Ibf/in and approximately 8 Ibf/in, and more particularly approximately 7.2 Ibf/in. However, other spring rates can be used. The return spring 68 can be selected based on the spring rate, thereby allowing the push pad assembly 10 to be tuned for a particular application.
In one illustrative embodiment, the damper spring 60 has an overall length of approximately 1.05 inches and an outside diameter of approximately 0.72 inches, with 6 total coils and 4 active coils. The return spring 68 has an overall length of approximately 2.15 inches and an outside diameter of approximately 0.72 inches, with 13 total coils and 11 active coils. However, other shapes and sized of spring can be used.
In various embodiment, the damper spring 60 may be replaced by other devices or materials which exhibit the same or better dampening characteristics. For example, polyurethane and felt may be used.
In operation, the push pad assembly 10 is attached to a door (not shown) as is known in the industry. When the door is to be opened, the touch bar 12 of the push pad assembly 10 is pushed or depressed. As the touch bar 12 is depressed, the touch bars scissors 14 are engaged, causing the link bar mounting portions 18 to move in a direction which is transverse to the motion of the touch bar 12. In the illustrative embodiment shown in the
As the link bar 34 is moved, the spring block 44, which is attached to the link bar 34, is also moved. The movement of the spring block 44 causes the second return spring engagement projection 56 of the spring block 44 to engage the second return spring engagement end 72 of the return spring 68. As this occurs, the movement of the link bar 34 and the touch bar 12 is permitted to continue, as the spring rate of the return spring 68 is not sufficient to prevent the movement of the link bar 34 or the touch bar 12 when a typical force is applied to the touch bar 12.
Movement of the link bar 34 and the touch bar 12 continues until the first damper spring engagement projection 50 of the spring block 44 engages the spring block engagement member 62 of the damper spring assembly 58 on the first damper spring engagement end 64. As this occurs, the force required to move the link bar 34 and the touch bar 12 is significantly increased, as the movement is opposed by both the return spring 68 and the damper spring 60. As the damper spring 60 has a high spring rate, the force that must be applied to the touch bar 12 must be substantially increased to allow the movement to continue.
In general, the latch 74 will disengage from the opening (not shown) in the door frame (not shown) prior to or approximately that same time as the first damper spring engagement projection 50 of the spring block 44 engages the spring block engagement member 62 of the damper spring assembly 58.
When engaged, the damper spring 60 dampens or prevents the continued movement of the link bar 34 and the touch bar 12. The use of the damper spring 60 limits the travel of the link bar 34 and the touch bar 12, thereby dampening the sound when the touch bar 12 is depressed, as the components (in particular the metal components) of the push pad assembly will be prevented from engaging each other with significant force.
When the touch bar 12 is disengaged, the compression force applied to the return spring 68 and the damper spring 60 is removed, allowing the return spring 68 and the damper spring 60 to return toward their unstressed position. As this occurs, the second return spring engagement end 72 of the return spring 68 remains in engagement with the second return spring engagement projection 56 of the spring block 44 to return the link bar 34 and the touch bar 12 to their initial position. Initially, of the damper spring 60 has been engaged, the first damper spring engagement end 64 of the damper spring 60 engages the first damper spring engagement projection 50 of the spring block 44 to additionally facilitate the return the link bar 34 and the touch bar 12 to their initial position.
Return movement of the link bar 34 and the touch bar 12 continues until the second damper spring engagement projection 52 of the spring block 44 engages the spring block engagement member 62 of the damper spring assembly 58 on the second damper spring engagement end 66 of the damper spring 60. As this occurs, the force required to move the link bar 34 and the touch bar 12 is significantly increased, as the return movement is opposed by both the damper spring 60. Consequently, as the damper spring 60 has a high spring rate, the damper spring 60 dampens or the return movement of the link bar 34 and the touch bar 12. The use of the damper spring 60 limits the travel of the link bar 34 and the touch bar 12, thereby dampening the sound when the touch bar 12 is returned to the initial position, as the components (in particular the metal components) of the push pad assembly will be prevented from engaging each other with significant force.
While the invention has been described with reference to an illustrative embodiment, it will be understood by those skilled in the art that various changes may be made, and equivalents may be substituted for elements thereof without departing from the spirit and scope of the invention as defined in the accompanying claims. One skilled in the art will appreciate that the invention may be used with many modifications of structure, arrangement, proportions, sizes, materials and components and otherwise used in the practice of the invention, which are particularly adapted to specific environments and operative requirements without departing from the principles of the present invention. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being defined by the appended claims, and not limited to the foregoing description or embodiments.
This application claims priority to U.S. Provisional Pat. Application Ser. No. 63/313,294 filed on Feb. 24, 2022 which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 63313294 | Feb 2022 | US |
