Height adjustable arm rest assembly

A height adjustable arm rest assembly for use on a chair, said arm rest assembly comprising:

• a support member having a substantially continuous inner surface that defines a cavity;
• an arm rest member having a stem extending generally downward therefrom and slidably received within said cavity of said support member;
• a locking mechanism attached to said arm rest member in order to secure said arm rest member in a selected vertical position relative to said support member, said locking mechanism comprising:
• an actuation member;
• a link connected to said actuation member and extending downward therefrom;
• and
• a cam pivotably connected to a lower portion of said link and positioned adjacent the continuous inner surface of the support member and positioned partially within a recess in said arm rest member, said recess sized slightly larger than a rear portion of said cam in order to allow said cam to pivot about a generally horizontal axis through said rear portion of said cam from a first position to a second position within said recess, said cam having a front surface that is movable into and out of engagement with said continuous inner surface of said support member in response to said actuation member in order to thereby provide the arm rest member with selective height adjustability.

A height adjustable arm rest assembly for use on a chair, said arm rest assembly comprising:

• p1 a support member having a substantially D-shaped and continuous inner surface that defines a cavity;
• an arm rest member having a stem extending generally downward therefrom and slidably received within said cavity of said support member, said arm rest member including a first recess and a second recess;
• a locking mechanism attached to said arm rest member in order to secure said arm rest member in a selected vertical position relative to said support member, said locking mechanism comprising:
• an actuation member;
• a link connected to said actuation member and extending downward therefrom, said link having an upper portion and a lower portion, said lower portion including a pivotable laterally extending lever arm;
• a cam pivotably connected to said link and positioned directly adjacent said continuous inner surface of said support member, said cam having a front portion and a rear portion, said rear portion received within said first recess, said first recess sized slightly larger than a rear portion of said cam in order to allow said cam to pivot from a first position to a second position within said recess;
• and
• a locking element resting on an end portion of said lever arm of said link, said locking element received within said second recess.

A height adjustable arm rest assembly for use on a chair, said assembly comprising:

• a support member having a sleeve that extends upwardly from said chair, the support member further including a substantially continuous engagement surface on an inner surface of the sleeve;
• an arm rest member including a downwardly extending stem which is slidably received within the sleeve;
• a locking mechanism attached to one of said support member and said arm rest member, said locking mechanism comprising:
• an actuation member
• a link connected to the actuation member;
• a generally wedge-shaped recess in the stem which opens toward the engagement surface;
• a cam received within the recess, said cam including a front, middle and rear portion, said middle portion being connected to said link, said cam being of a size and shape so as to allow the cam to pivot in response to movement of the actuation member, the cam pivotable within the recess about a generally horizontal axis through the rear portion of the cam between a locking position wherein the front portion of the cam engages the engagement surface in the sleeve and a release position wherein the cam disengages the engagement surface, and wherein the cam has a length great enough to prevent the cam from pivoting past the locking position.

A height adjustable arm rest assembly for use on a chair, said assembly comprising:

• an arm rest member having a sleeve with a substantially continuous engagement surface on an inner surface of the sleeve;
• a support member for attachment to said chair and extending substantially upward therefrom, said support member including a stem adapted to extend upwardly from said chair;
• a locking mechanism attached to said support member, said locking mechanism comprising:
• an actuation member
• a link connected to the actuation member;
• a generally wedge-shaped recess in the stem which opens toward the engagement surface;
• a cam received within the recess, said cam including a front, middle and rear portion, said middle portion being connected to said link, said cam being of a size and shape so as to allow the cam to pivot in response to movement of the actuation member, the cam pivotable within the recess about a generally horizontal axis through the rear portion of the cam between a locking position wherein the front portion of the cam engages the engagement surface in the sleeve and a release position wherein the cam disengages the engagement surface, and wherein the cam has a length great enough to prevent the cam from pivoting upward past the locking position.