MXPA97009895A - Adjustment height armrests assembly - Google Patents

Abstract

The present invention relates to an adjustable height armrest assembly for use in a chair, characterized in that said armrest assembly comprises: a support member, an armrest member connected to the support member, the support member and the armrest member extending. substantially coaxial, one of the supporting member and the armrest member is movable with respect to the armrest member, an securing mechanism connected to one of the support member and the armrest member, so as to secure the armrest member in a selected vertical position with respect to the support member, said securing mechanism comprising: an actuating member, a strut connected to the actuating member, and a cam pivotally connected to the strut, the cam having a front portion and a rear portion; the rear portion is received within a depression in one of between the supporting member and the supporting member azos, the depression having a dimension slightly larger than the rear portion of the cam in order to allow the cam to move pivotally about a generally horizontal axis through the rear portion of the cam, from a first position to a second position Within the depression, and one engaging surface substantially continuous in the other between the supporting member and the armrest member, the cam positioned adjacent the continuous engaging surface, and can pivotally move toward and away from engagement with the surface of the coupling member. continuous coupling, in response to the actuating member, in order to thereby provide in the armrest member, a height adjustment capability selecti

Description

ADJUSTABLE HEIGHT ARMRESTS ASSEMBLY BACKGROUND OF THE INVENTION The present invention relates to the field of armrests for use in chairs. More particularly, the invention relates to the field of armrests that are adjustable at selected heights to provide a more comfortable chair for a user. Chairs, particularly office chairs, are often designed with the armrests secured in a fixed position, based on the intended use of the chair and the average size of the expected users. However, in an office environment, people of different sizes can spend many hours in a chair. Therefore, it is convenient to have armrests that are adjustable to match the specific anatomy of a particular user. A chair, particularly armrests, should be comfortable for people of all sizes and in all forms. Similarly, the armrests must be adjustable, depending on the different activities of the user of the chair. For example, a user may want an armrest at a first height when working with pen and paper on a desk, but want a second height when working with a computer. Some adjustable armrests have been described in the prior art. For example, in US Patent No. 4,951,995, issued to Teppo and co-inventors, a complex mechanism for adjusting the height of the arm for a chair is described. A vertical movement translation mechanism interconnects two laterally spaced armrests. A cable assembly, together with a rotating gear, move the movement of a first arm to a corresponding movement in the second arm, thereby providing synchronized movement of the armrest assembly. U.S. Patent No. 4,884,846, issued to Tobler, discloses armrests with limited height adjustment capabilities. The armrest is adjusted through the rotation of a carrier element on the armrest support. The supporting element is a two-part bolt construction, with right and left threads coupled together by the carrier element. While the armrests described above have been previously known, there is still a need for adjustable armrests that provide reliable operation.

BRIEF DESCRIPTION OF THE INVENTION In short, the present invention is directed to an adjustable height armrest assembly, for use in a chair. According to one aspect of the invention, the armrest assembly includes a support member, an armrest member, an securing mechanism, connected to one of the support member and the armrest member; and a substantially continuous engagement surface on the other of the support member and the armrest member. The supporting member is connected to the chair and extends substantially upwards therefrom. The armrest member is movably attached to the support member and extends substantially coaxial therewith. The securing mechanism is connected to one of the support member and the armrest member, in order to secure the armrest member in a selected vertical position, with respect to the support member. The securing mechanism includes an actuating member, a strut connected to the actuating member and a cam pivotally connected to the strut. The cam has a front portion and a rear portion. The rear portion is received within a depression in one of the support member and the armrest member. The depression has a slightly larger dimension than the rear portion and the cam, so as to allow the cam to move pivotally about a generally horizontal axis, through the rear of the cam. The cam is pivotally movable from a first position to a second position within the depression. A substantially continuous engaging surface is located in the other between the support member and the armrest member. The cam is located adjacent to the continuous coupling surface and is pivotable towards and away from engagement with the continuous coupling surface, in response to the actuation member, in order thereby to provide the armrest member with a selective height adjustment capability. According to another aspect of the present invention, the securing mechanism is connected to the armrest member and the continuous coupling surface is formed on the inner surface of the support member. In accordance with another aspect of the present invention, the lower portion of the actuator includes a lever arm that contacts a pin disposed in a second depression of the armrest member. According to yet another aspect of the present invention, a T-shaped limiting member is located in a correspondingly shaped opening in a lower portion of the armrest member. The limiting member includes an embossed surface that moves within a channel in the support member. As used herein, the term "continuous coupling surface" is intended to include surfaces that are perfectly smooth or that are slightly irregular, for example, which include shallow grooves in them. Also as used here, the elements are "decoupled" when they are able to move substantially one with respect to the other. The present invention, together with the objects and advantages that are proper to it, will be better understood with reference to the following detailed description, when read in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a partial sectional side view of a first preferred embodiment of the adjustable height armrest assembly of the present invention, with the armrest member immobilized in its position at a first height. Figure 2 is a side view in partial section of the preferred embodiment of the present invention shown in Figure 1, with the armrest member in the unlocked position, at a second height. Figure 3 is an exploded view of the preferred embodiment shown in Figures 1-2. Figure 4 is a side view in partial section of the lower portion of an armrest assembly of another preferred embodiment of the present invention, with the armrest member shown in the locked position. Figure 5 is a side view in partial section of the lower portion of an armrest assembly of the preferred embodiment of the present invention shown in Figure 4, with the armrest member shown in the unlocked position; and Figure 6 is a side view in partial section of another preferred embodiment of the present invention, with the armrest member shown with a sleeve and with the support member shown with a rod.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES Referring to the drawings, Figure 1 shows an adjustable armrest assembly 10 for use in a chair according to the present invention. The assembly 10 includes a support member 12 or tube that is attached to a chair under its seat. As shown in Figure 3, a mounting member 13 extends outwardly from under the seat, the support member 12 extending vertically upwards therefrom. The support member 12 has an internal passage 14 that movably receives the armrest member 16. The passage 14 is defined by the inner wall 18 in the form of D. In a first preferred embodiment, the inner wall 18 is knurled to include a plurality of shallow horizontal notches. Preferably the notches have an approximate depth of 0.101 to 0.152 microns. In another preferred embodiment, the inner wall 18 is substantially smooth. While the support member 12 can be formed from many different materials, known to those of ordinary skill in the art, the support member 12 is preferably formed of aluminum, using a die casting process. The armrest member 16, preferably formed from nylon polyamide filled with 30% glass, is received movably within the passageway 14. As shown in Figure 3, the armrest member 16 has an upper surface 20 which it is connected to the adjustable armrest housing 22. The pad 23 of the arm is secured to the housing 22, in order to support the arm of a user therein. For a description of the accommodation 22 of the adjustable armrest, reference is made to the assigned application, same as the present one, filed on June 7, 1995, in the name of Douglas Van De Riet and Jeffery Webber, entitled Adjustable arm rest, whose description is expressly incorporated at the moment. A passage 26 extends downwardly from the upper surface 20 and substantially along the rod 28. The slot 29 opens into the passage 26 and runs along the entire rod 28. A first cavity 30 is connected to the passageway 26. , adjacent to the upper surface 20 of the armrest member 16. A second cavity 36, T-shaped, is located in a lower portion 38 of the rod 28. A third cavity 40, substantially circular, is opens to the second cavity 36. Markings 42 may be placed along the rod 28 to allow a user to gauge the relative position of the armrest member 16 and the support member 12. An actuation member 50 is pivotally mounted within the first cavity 30 of armrest member 16. The button 52 extends downwards and outwards from the first cavity 30. A pin 54 is mounted within the armrest member 16 and passes through an opening 56 in the armrest member 16, an opening 47 in the member 50 and again towards the armrest member 16. The pin 54 defines a pivot axis around which the actuation member 50 moves when it is depressed by a user. A small hammer 58 projects outward from the end 60 of the actuation member. Further, a spring engaging finger 62 is located slightly above the hub 58 and extends in a direction along the length of the housing 22. In a first embodiment, the actuation member 50 is made of ABS polycarbonate and the 54 steel pin (12L14). A U-shaped spring 70 acts to engage the actuation member 50. The spring 70 is mounted within the upper portion 71 of the passage 26. The end portion 72 of the spring 70 engages a mounting flange within the passage 26. The curved portion 74 of the spring 70 engages the actuation element 50, just below the finger 62. The finger 62 secures the curved portion 74 of the spring 70 to the actuation element 50. In a preferred embodiment, the wire spring 70 is fabricated. of piano. The brace 80, preferably made of nylon filled with 30% glass, is connected to the end 60 of the actuating member 50. More specifically, the brace 80 has an opening 82 having a dimension movingly receiving the hub 58. The portion lower 86 of strut 80 has a cutout portion 88. In addition, finger 90 projects downwardly and outwardly from beneath cutout 88 and projects toward inner wall 18 of support member 12. As shown in figures 1 and 2 a cam or wedge 94 is movably connected to the strut 80 within the cutout 88. The cam 94 has a centrally located opening 101, which receives the small hub 102 which extends from the lower portion 86 of the strut 80. The cam 94 has a front portion 96 and a rear portion 98. Rear portion 98 is received within a depression 100, within the rod 28 of armrest member 16. In this preferred embodiment, the depression 100 has a substantially V-shaped or wedge-shaped configuration, and a curved rear wall 103, which substantially adapts to the rear portion 98 of the cam 94. The depression 100 has a substantially substantial width. equal to the width of the cam 94 and opens towards the inner wall 18 of the support member 12. The front portion 96 of the cam 94 has a plurality of teeth 103 extending longitudinally. While the cam 94, like the other elements of this invention, can be made of many different materials known to those of ordinary skill in the art, preferably a powdered metal (FN 0205) is used to make the cam 94. A T-shaped limiting member 110 is received within the second cavity 36 correspondingly, with the spring 112 captured within the third cavity 40. The spring 112 acts to load the lower portion 114 of the limiting member 110 toward engagement with a channel 115 running vertically along the inner wall 18 of the support member 12. More specifically, the spring 112 urges the rib 116 toward engagement with the channel 115. The channel 115 terminates within the upper portion of the support member 14, In order to prevent the armrest member 16 from being pulled out of engagement with the support member 12. The T-shaped limiting member 110 can be manufactured using spring steel and the spring 112 using piano wire. To adjust the height of the armrest member 12, example, from the height of Figure 1 to that of Figure 2, a user imposes an upward e on the actuation member 50. More particularly, a user imposes an upward e on the button 52, sufficient to overcome the opposite directional e created by the spring 70. As shown in figure 2, when the button 52 is pushed upwards, the actuating element 40 moves pivotally about the axis defined by the pin 54. End 60 is directed downward with a resultant downward e applied to strut 80. As shown in Fig. 2, cam 94 moves pivotally then downwardly., from engagement with the inner surface 18 of the support member 12. More specifically, due to the restricted movement of the cam 94 caused by the depression 100, the cam 94 moves pivotally downward about a horizontal axis defined by the rear portion of the cam. Then the teeth 103 of the inner wall 18 are substantially decoupled. With the cam 94 in that downward-angled position, a user could then move the armrest member 16 upward or downward, as desired. After adjusting the armrest member 16 to a new height (either higher or lower), the user then releases the button 52 of the actuation member 50. As a result, the spring 70 pulls up the end 60 of the actuation member 50. The cam 94 is then wedged again into engagement with the inner surface 18 of the support member 12, as shown in Fig. 1. In particular, the cam 94 returns to a substantially horizontal position, so that the teeth 103 engage f with the inner wall 18 of the support member 12, in order to secure the armrest member 16 at its new height. In a preferred embodiment, the armrest member 16 has a movement scale of approximately 10.16 cm. Additionally, it should be noted that, when the user pushes down on the armrest member 16 with his elbow or forearm during use, the cam 94 is further wedged in engagement with the inner wall 18 and the depression 100, so that further ensures the armrest member 16 at the selected height. According to another aspect of the present invention the armrest member 16 can not be taken out of engagement with the support member 12. In particular, the rib 116 in the limiting member 110 is moved within the channel 115 of the support member 12. However , because the channel 115 terminates in the upper portion of the support member 12, the rib 116 will run towards the end of the channel 115, preventing the armrest member 16 from being pulled out of engagement with the support member 12. Another preferred embodiment of the present invention is shown in Figures 4 and 5. In general, the mode operates in a manner similar to the embodiment shown in Figures 1-3. However, that embodiment prevents the armrest member from being moved up by a user without pressing the button on the actuation member. A lever arm 200 extends outward from the lower portion of the strut 202 and is pivotally connected thereto. The lever arm 200 has a small flange 204 extending along its lower surface. The flange 204 engages the depression 206 and, in particular, the bottom wall 208. Consequently, the lever arm 200 is spaced from the bottom wall 208. The pin 210 abuts the cavity 211 defined by the bottom wall 212. of the armrest member 213. In a preferred embodiment, the pin 210 has a knurled outer surface. The lower wall 212 has a vertically extending upper portion 214, and a ramp surface 215 that extends toward the inner wall 216 of the support member 217. The cam 218 is pivotally connected to the brace 202 and functions in the same general manner as described above. In operation, the embodiment of Figures 4-5 functions to prevent a user from moving the armrest member upwardly without depressing the actuation member. More specifically, as shown in Figure 4, when the actuation member is not depressed, the pin 210 is wedged between the inner wall 216 and the ramp 215. Consequently, the pin 210 prevents the armrest member 213 from being moved. up when it is in this position. In contrast, as shown in Figure 5, when the actuation member is depressed, the strut 202 pushes down on the end of the lever arm 200. The lever arm 200 then moves pivotally around the shoulder 204 imposes itself a rising force on the pin 210. The pin 210 is then pushed out of engagement with the ramp 215, towards the widest portion of the cavity 211, defined by the upper portion 214. As a result, an armrest member 213 is then movable in the upward direction, because the user has depressed the actuation member. When the user releases the actuation member, the lever arm 200 is pivotally moved back to the position shown in Figure 4. In this position, the armrest member 213 is locked in place again.

It should be recognized that the specific male / female relationship of the elements of this invention could be modified by those of ordinary skill in the art, in order to still practice the present invention. For example, the preferred embodiment of the armrest assembly of the present invention could be modified as shown in Figure 6. In general, the preferred embodiment of Figure 6 operates in a manner very similar to the preferred embodiment of Figures 1 -3. However, in contrast to the preferred embodiment shown in Figures 1-3, the armrest assembly 300 shown in Figure 6 has a support member 312 that includes an actuation element 350, the strut 380, the cam 394 and the depression 400. Further, in contrast to the preferred embodiment of Figures 1-3, the support member 312 has a rod 315 (a male element) that extends upward and engages a sleeve 319 (a female element) in the member. 316 armrest. In a preferred embodiment, the inner wall 345 of the sleeve 319 is substantially smooth and forms a mating surface that interacts with the cam 394. The armrest housing 322 receives an arm pad that would support a user's arm. As shown in Figure 6, the armrest member 16 is locked in a fixed position. In order to adjust the height of the armrest member 316, a user would depress the actuation element 350 in order to disengage the cam 394 from the inner wall 345 of the sleeve 319. At that point, the armrest member 36 could be moved to a new height by the user. Once the user releases the actuation element 350, the cam 394 would pivotally move back to engagement with the inner wall 345 of the sleeve 319. The armrest member 316 would then be fixed in its position at a new height. The described modalities are illustrative and not restrictive. The scope of the invention is indicated by the claims instead of by the preceding description. The invention can be incorporated into other specific forms, without departing from the spirit of the invention. For example, as described above, the connection of the cam and the continuous engagement surface, with respect to the support member and the armrest member, could be interchanged. Similarly, you could also change the materials used or the exact configuration of any of the parties, as will be recognized by those who are ordinary experts in the field. Accordingly, it is intended that all changes that fall within the scope of the claims are included herein.

Claims (30)

NOVELTY OF THE INVENTION CLAIMS

1. - An adjustable height armrest assembly, for use in a chair, characterized in that said armrest assembly comprises: a support member; a support member attached to the support member; the support member and the armrest member being substantially coaxial; one of the support member and the armrest member is movable with respect to the armrest member; an securing mechanism connected to one of the support member and the armrest member, in order to secure the armrest member in a selected vertical position with respect to the support member; said securing mechanism comprising: an actuating member; a tie connected to the actuation member; and a cam connected pivotally to the strut; the cam having a front portion and a rear portion; the rear portion is received within a depression in one of the support member and the armrest member; the depression having a dimension slightly larger than the rear portion of the cam in order to allow the cam to move pivotally about a generally horizontal axis through the rear portion of the cam, from a first position to a second position within the Depression; and a substantially continuous engagement surface in the other between the support member and the armrest member; the cam is located adjacent to the continuous coupling surface, and can pivotally move toward and away from engagement with the continuous coupling surface, in response to the actuation member, so as to thereby provide in the armrest member, a capacity of selective height adjustment.

2. The height-adjustable armrest assembly according to claim 1, further characterized in that it comprises a requesting member connected to the securing mechanism, in order to forcibly carry the cam into engagement with the continuous coupling surface.

3. The height-adjustable armrest assembly according to claim 2, further characterized in that the soliciting mechanism comprises a U-shaped spring.

4. The height-adjustable armrest assembly according to claim 3, further characterized because the strap further includes an elastic foot member projecting down from below the cam, and contacting the continuous engaging surface.

5. The height-adjustable armrest assembly according to claim 4, further characterized in that the support member defines an opening through which the armrest member extends partially.

6. The height adjustable armrest assembly according to claim 5, further characterized in that the securing mechanism further includes a laterally extending pin, which passes through the actuation member and defines a pivot axis.

7. The height-adjustable armrest assembly according to claim 6, further characterized in that the armrest member has a T-shaped opening that receives a T-shaped limiting member, which has an embossed surface projecting towards

8. The height-adjustable armrest assembly of confounding with claim 7, further characterized in that the cam includes a curved rear portion and a plurality of teeth that are restrained within a channel extending within the supporting member. they extend longitudinally in the frontal portion.

9. The height-adjustable armrest assembly according to claim 8, further characterized in that the depression is defined by a curved rear surface.

10. An adjustable height armrest assembly for use in a chair, characterized in said armrest assembly, comprising: a support member having a substantially continuous internal surface defining a cavity; an armrest member having a rod that extends generally down therefrom and that is slidably received within the cavity of the support member; an securing mechanism connected to the armrest member in order to secure the armrest member in a selected vertical position with respect to the support member; comprising the insurance mechanism: an actuation member; a strap connected to the actuating member and extending downwardly therefrom; and a cam pivotally connected to a lower portion of the stay and located adjacent the continuous internal surface of the support member and partially positioned within a depression of the armrest member; the depression has a dimension slightly larger than a back portion of the cam, in order to allow the cam to pivot about a generally horizontal axis through the rear portion of the cam, from a first position to a second position within the depression; the cam has a front surface that is movable towards and away from engagement with the continuous internal surface of the support member, in response to the actuation member, so as to thereby provide selective height adjustment capability in the armrest member.

11. The height-adjustable armrest assembly according to claim 10, further characterized in that the support member has a channel extending substantially vertical therein, terminating before a limiter of the support member.

12. The height-adjustable armrest assembly according to claim 11, further characterized in that the armrest member has a T-shaped opening, which receives the T-shaped limiting member, which has an embossed projecting surface. outwards, which is received inside the channel.

13. The adjustable height armrest assembly according to claim 12, further characterized in that it further includes a spring received within an opening of the rod; by applying the spring to said raised surface of the limiting member, within the channel.

14. The height-adjustable armrest assembly according to claim 13, further characterized in that the cam includes a plurality of longitudinally extending teeth.

15. A height-adjustable armrest assembly for use in a chair, characterized in said armrest assembly, comprising: a support member having a substantially D-shape and a continuous internal surface defining a cavity; an armrest member having a rod extending generally down therefrom, and received slidably within the cavity of the support member; including the armrest a first depression and a second depression; an securing mechanism connected to the armrest member in order to secure the armrest support member in a selected vertical position with respect to the support member; said securing mechanism comprising: an actuating member; a strap connected to the actuating member and extending downwardly therefrom; the struts having an upper portion and a lower portion; said lower portion including a pivotable lever arm extending laterally; a cam pivotally connected to the strut and located directly adjacent to the continuous internal surface of the support member; the cam having a front portion and a rear portion; the rear portion being received within the first depression; the first depression being of a size slightly larger than a back portion of the cam, in order to allow the cam to move pivotally from a first position to a second position within the depression; and an securing element, which rests on an end portion of said strut lever arm; the securing element being received within the second depression.

16. The height adjustable armrest assembly according to claim 15, further characterized in that the second depression is defined by an angled surface extending upwards.

17. The adjustable height armrest assembly according to claim 16, further characterized in that the securing element is a pin.

18. The height-adjustable armrest assembly according to claim 17, further characterized in that it additionally comprises a solicitor member connected to the securing element, in order to forcibly carry the cam to engagement with the continuous coupling surface.

19. The adjustable height armrest assembly according to claim 18, further characterized in that the cam has a curved rear portion and a plurality of longitudinally extending teeth in the frontal portion.

20. An adjustable height armrest assembly according to claim 19, further characterized in that the depression is defined by a curved rear surface.

21. An adjustable height armrest assembly for use in a chair, characterized in that assembly comprising: a support member having a sleeve extending upwardly from the chair; the support member further including a substantially continuous engagement surface on an inner surface of the sleeve; an armrest member including a downwardly extending rod, slidably received within the sleeve; an securing mechanism connected to one of the support member and the armrest member; the securing mechanism comprising: an actuating member, a strut connected to the actuating member; a generally wedge-shaped depression, present in the rod, which opens towards the coupling surface; a cam received within the depression; the cam including a front portion, an intermediate portion and a rear portion; the intermediate portion being connected to the strut; the cam being of a size and shape that allows the cam to move pivotally in response to movement of the actuation member; the cam can pivot within the depression about a generally horizontal axis, through the rear portion of the cam, between an insuring position in which the front portion of the cam engages the coupling surface of the sleeve and a position loose in which the cam is uncoupled from the mating surface; and wherein the cam has a length large enough to prevent the cam from moving pivotally beyond the safe position.

22. The height-adjustable armrest assembly according to claim 21, further characterized in that the cam is pivotally moved downward so as to be disengaged from the mating surface.

23. The height adjustable armrest assembly according to claim 22, further characterized in that the depression has a width substantially equal to the width of the cam.

24. The height-adjustable armrest assembly according to claim 23, further characterized in that the rear portion of the cam defines a pivot axis about which the cam pivots.

25. - Adjustable height armrest assembly according to claim 24, further characterized in that the depression has a substantially V-shaped shape. - A height-adjustable armrest assembly for use in a chair, characterized in that assembly comprising: armrest member having a sleeve with a substantially continuous engagement surface on an inner surface of the sleeve; a support member connected to the chair and extending substantially upwards therefrom; the supporting member includes a rod extending upwardly from the chair; an securing mechanism connected to the support member; comprising the insurance mechanism: an actuation member; a tie connected to the actuation member; a generally wedge-shaped depression in the rod, which opens towards the coupling surface; a cam received within the depression; the cam including a front portion, a middle portion and a rear portion; the middle portion being connected to the strut; the cam is of a size and shape that allows the cam to move pivotally in response to the movement of the actuating member; the cam can move pivotally within the depression, about a generally horizontal axis, through the rear portion of the cam, between an insuring position, in which the front portion of the cam engages with the engaging surface in the sleeve and a loose position, in which the cam is uncoupled from the coupling surface. 27. The height-adjustable armrest assembly according to claim 26, further characterized in that the cam is pivoted downwardly in order to uncouple from the coupling surface. 28. The height adjustable armrest assembly according to claim 27, further characterized in that the depression has a width substantially equal to a width of the cam. 29. The height adjustable armrest assembly according to claim 28, further characterized in that the rear portion of the cam defines a pivot axis about which the cam pivots. 30. The height adjustable armrest assembly according to claim 29, further characterized in that the depression has a substantially V.