| Device for adjusting the degree of preload of the springs in office chair mechanisms -> Monitor Keywords |
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Device for adjusting the degree of preload of the springs in office chair mechanismsDevice for adjusting the degree of preload of the springs in office chair mechanisms description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20060208548, Device for adjusting the degree of preload of the springs in office chair mechanisms. Brief Patent Description - Full Patent Description - Patent Application Claims
[0001] This invention relates to a device for adjusting the degree of preload of the springs in office chair mechanisms. [0002] Devices for adjusting the degree of preload of the springs in office chair mechanisms are known, consisting of a knob acting on a stem disposed in the spring interior. [0003] A drawback of this system is the fact that, given the vertical position of the spring below the box structure supporting the seating portion, there is a certain difficulty in operating the mechanism. [0004] To obviate this drawback, solutions have been proposed in which the mechanism is situated in a lateral horizontal position so that mechanical means can be used to adjust the degree of compression of the spring. [0005] This solution presents however the drawback of being usable only on chairs of new design, and cannot be applied to mechanisms already available commercially. [0006] An object of the invention is to eliminate this drawback by providing an adjustment system able to preload the springs in office chair mechanisms, which can be mounted on commercially available box structures. [0007] This and further objects which will be apparent from the ensuing description are attained according to the invention by a device for adjusting the degree of preload of springs in office chair mechanisms as described in claim 1. [0008] A preferred embodiment of the present invention is described in detail hereinafter with reference to the accompanying drawings, in which: [0009] FIG. 1 is an exploded perspective view of the adjustment device of the invention applied to a box structure, [0010] FIG. 2 shows it in longitudinal section in its assembled configuration, and [0011] FIG. 3 shows a variant thereof. [0012] As can be seen from the figures, the adjustment device of the invention is applied to a swivel support indicated overall by 2 comprising a fixed box structure 4 provided lowerly with a frusto-conical bush for the insertion of the upper end of the stem of a traditional gas spring (not shown in the drawings), the purpose of which is to support the swivel support on a resting base and at the same time to adjust the height of the seating portion. [0013] The flanges 12 of a plate 14 supporting a seating portion (not shown in the drawings) are hinged, about a tubular shaft 10, to the longitudinal walls 8 of said box structure, said flanges 12 also being hinged about another transverse shaft 16 to an elongate plate 18 for supporting the back-rest (not shown in the drawings) which in its turn is hinged by its flanges 20 to the longitudinal walls 8 of the box structure about a transverse pin 22. [0014] The surface of the plate 18 comprises a seat provided with a hole 24 in which there engages a pull rod 26 inserted into the adjustment device indicated overall by 28. [0015] The device comprises a double-bodied socket, housing in its interior a coil spring 30 concentric with the pull rod and resting with its free end on a plug 32 in which the head of a nut engaging the threaded end of the pull rod rests. [0016] Specifically, the adjustment device comprises a first socket 36, the base of which is inserted in a seat 38 provided in the base of the box structure, and of which the free edge 40 of its lateral surface extends helically at 44. [0017] In the interior of the first socket there is inserted a second socket 42 the outer lateral surface of which comprises a helical rib cooperating with the free edge of the first socket. [0018] In addition, the outer lateral surface of the first socket 36 comprises a rack portion 46 in which there engages a worm 48 provided with an operating knob (not show in the drawings) which is secured to the parallel arms 50 of a U bracket 52 rigid with the base of the box structure. [0019] The parallel arms 50 are provided with two lips 54 which engage between the prongs of two forks 56 provided on the outer lateral surface of the second socket 42. [0020] The device of the invention operates in the following manner: [0021] in the absence of external stresses, for example when the user is not seated on the chair, the spring 30 maintains the box structure and hence the support plate 14, and the plate 18 hinged to it, in a virtually advanced chair position. [0022] This configuration is made stable exclusively by the counteracting effect due to the spring 30. When the user is seated on the chair, the user's weight acts as a lever against the back-rest to modify the compression undergone by the spring. [0023] When in that configuration the back-rest and the seating portion can be freely inclined rearwards by the effect of the thrust of the user seated on the seat, and forwards by decreasing this thrust by a sufficient extent to enable the spring to exert its elastic reaction. [0024] As the weight of the user varies, the intensity of the force required to overcome the spring also varies, and for this reason the device is able to adjust the reaction of this spring, by adjusting its preload. Continue reading about Device for adjusting the degree of preload of the springs in office chair mechanisms... Full patent description for Device for adjusting the degree of preload of the springs in office chair mechanisms Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this Device for adjusting the degree of preload of the springs in office chair mechanisms patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. Start now! - Receive info on patent apps like Device for adjusting the degree of preload of the springs in office chair mechanisms or other areas of interest. ### Previous Patent Application: Recline adjustment apparatus Next Patent Application: Automotive seat with control system Industry Class: Chairs and seats ### FreshPatents.com Support Thank you for viewing the Device for adjusting the degree of preload of the springs in office chair mechanisms patent info. IP-related news and info Results in 0.11838 seconds Other interesting Feshpatents.com categories: Software: Finance , AI , Databases , Development , Document , Navigation , Error 174 |
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