GB2294873A

GB2294873A - A support mechanism for a keyboard

Info

Publication number: GB2294873A
Application number: GB9521740A
Authority: GB
Inventors: Victor Peck
Original assignee: HOOD COMPUTERS Pty Ltd
Current assignee: HOOD COMPUTERS Pty Ltd
Priority date: 1994-10-25
Filing date: 1995-10-24
Publication date: 1996-05-15
Also published as: AUPM901194A0; GB9521740D0; DE19539686A1

Description

1 A Support Mechanism for a Keyboard 2294873

Technical Field

The present invention relates to height adjustment mechanisms and more particularly but not exclusively to mechanisms to be employed in desks to provide a height adjustable work surface.

Background of the Invention

Described in Australian Patent Application 19015/88 is a hinge assembly for incorporation in a desk. The desk would have a work surface, a portion of which is height adjustable. The height adjustable portion would be supported by the hinge 1 o assembly.

Described in Australian Patents 635803 and 637320 are keyboard support apparatus. In both these specifications, a plate is provided and extends from a pair of parallel arms. The plate is displaced laterally in order to effect height adjustment. A further mechanism disclosed in Patent 637320 has a pivotally mounted lever which moves a pin into and out is of engagement with an apertured plate fixed to the pair of parallel arms. The pivoted lever moves laterally relative to the arms.

Summary of the Invention

There is disclosed herein a height adjustment mechanism for a work surface, said mechanism comprising:

a base; a pair of arms each having opposite end portions and pivotally attached at adjacent end portions to said base, said arms being adapted for pivoting movement about respective first parallel pivot axes, which first pivot axes are generally parallel and generally transverse of the longitudinal direction of extension of the arms; a support member pivotally attached to end portions of said arms remote from said base, the remote end portions being pivotally attached to said support member for pivoting movement relative thereto about second parallel pivot axes, which second axes are generally transverse of the general direction of extension of the arms; and [NAUBTn00297:DSS 2 locking means operable to prevent pivoting of said arms in a predetermined direction relative to said base, said locking means comprising an elongated member and a clamp member to engage said elongated member, said clamp member and elongated member being arranged so that pivoting of said arms cause relative displacement between the clamp member and elongated member along said elongated member so that the displacement of the support member with respect to the base is determined by the position at which the clamp member engages the elongated member.

Brief Description of the Drawings

A preferred form of the present invention will now be described by way of example lo with reference to the accompanying drawings wherein:

Figure 1 is a schematic top plan view of a height adjustment mechanism for a desk; Figure 1A is a schematic side elevation of a portion of the height adjustment mechanism of Figure 1 as seen in the direction 1A of Figure 1; Figure 2 is a schematic side elevation of the height adjustment mechanism of Figure 1; Figure 3 is a further schematic side elevation of the height adjustment mechanism of Figure 1; Figure 4 is a schematic top plan view of a locking means employed in the height adjustment mechanism of Figures 1 to 3; Figure 5 is a schematic top plan view of a portion of the locking means of Figure 4; Figure 6 is a schematic top plan view of the portion of Figure 5, with the locking means engaged; Figure 7 is a schematic front elevation of part of the locking means of Figure 4; Figure 8 is a schematic side elevation of a height adjustment mechanism for a desk; Figure 9 is a schematic bottom plan view of a portion of the locking mechanism employed in the height adjustment mechanism of Figure 8; Figure 10 is a schematic side elevation of the height adjustment mechanism of Figure 8 in a further configuration; [N:\LIBTI]00297:DSS 3 Figure I I is a schematic front elevation of a portion of the height adjustment mechanism as seen in Figure 10; Figure 12 is a schematic rear elevation of a portion of the height adjustment mechanism as seen in Figure 10; Figure 13 is a schematic side elevation of the portion shown in Figure 12; Figure 14 is a schematic further side elevation of the portion shown in Figure 12; Figure 15 schematically depicts an alternate locking mechanism to that employed in the devices of the previous figures; Figure 16 is a schematic side elevation of a height adjustment mechanism for a 1 o desk; Figure 17 is a top plan view of the mechanism of Figure 16; and Figure 18 is a further side elevation of the mechanism of Figure 16.

Detailed Description of the Preferred Embodiment

In Figures 1 to 7 of the accompanying drawings there is schematically depicted a height adjustment mechanism 10 for a desk. The desk would have a first bench part 11 which is generally stationary, and a height adjustable bench part 12 supported by the mechanism 10. The mechanism 10 would be operable to raise and lower the bench part 12.

The height adjustment mechanism 10 includes a base 13 which is fixed to the bench part 11, and a support member 14 fixed to the bench part 12. Extending between the base 13 and support member 14 is a pair of generally parallel arms 15 and 16. The arms 15 and 16 each have opposite ends pivotally attached to the base 13 and support member 14 by means of pivot assemblies 17 and 18. In this embodiment, the pivot assemblies 17 are spaced by the same distance as the pivot assemblies 18. Similarly, the pivot assemblies 17 and 18 at the base 13, are spaced by the same distance as the pivot assemblies 17 and 18 at the support member 14. However it should be appreciated that this configuration has been provided in order to maintain the orientation of the bench part 12. More particularly, as the bench part 12 is height adjusted, it will remain horizontal. However it [N:kLU37r100297:DSS 4 should be appreciated that other configurations are possible so that the bench part 12 may be gradually inclined with pivoting movement of the arms 15 and 16.

The mechanism 10 further includes a locking device 19 which is operable by a user to maintain the part 12 at a desired height. In this embodiment, the locking device 19 includes a rod 20 which is pivotally attached to the base 13 by a pivot assembly 21. The rod 20 extends to a clamp assembly 22 including a clamp member 23. The clamp member 23 is a plate fixed to the extremity of a handle 24. The handle 24 extends to adjacent the edg6 of the bench part 12 at which edge a user would be generally seated. The end 25 of the handle is positioned so that the bench part 12 can be height adjusted single handedly, that is with the user gripping the edge of the bench part 12 adjacent the end 25. The clamp member 23 passes through an aperture 26 in the support member 14 so as to pivot about an axis defined by the aperture 26. The clamp member 23 also has an aperture 27 through which the rod 20 passes. When the clamp member 23 is generally perpendicular to the rod 20, the rod 20 can slide through the aperture 27. However, when the clamp member 23 is inclined (as shown in Figure 6) the clamp member 23 engages the rod 20 and prevents it from moving in the direction of the arrow 28. A spring 29 extends between a flange 35 and the clamp member 23 to cause the member 23 to incline to securely engage the rod 20. The flange 35 is fixed to the support member 14. The flange 35 has a slot 36 through which the rod 20 slidably passes. The slot 36 needs to be elongated as illustrated in Figure 7, so as to accommodate pivoting movement of the rod 20 about the pivot assembly 21.

By an operator causing pivoting of the lever 24 in the direction of the arrow 37, the clamp member 23 releases the rod 20 and therefore permits lowering of the bench part 12. In this regard it should be appreciated that in this embodiment, the clamp member 23 will automatically release the rod 20 when the bench part 12 is raised. The clamp member 23 will only permit relative movement of the rod 20 with respect to the clamp member 23 in the direction of the arrow 8 when the handle 24 is pivoted in the direction of the arrow 37.

[N:MBTr100297:DSS In the above described preferred embodiment, the desk part 12 can be held in any desired position and is not limited to incremental adjustment as would be the case where the locking mechanism employed teeth. The height of the desk part 12 is determined by the position at which the clamp member 23 engages the rod 20. By extending "diagonally" with respect to the parallel legs 15 and 16, the locking mechanism 19 will maintain the bench part 12 at the desired height.

Preferably the mechanism 10 would be accompanied by a parallel mechanism 30 which would aid in supporting the desk part 12. The mechanism 30 would include a base 31 and a support member 32. The base 32 would be fixed to the desk part 11, while the member 32 would be fixed to the desk part 12. Extending between the base 31 and support member 32 is a pair of parallel arms 33 which are pivotally attached at opposite ends by pivot assemblies 34 to the base 31 and support member 32. A brace member 35 would maintain the mechanism 10 and mechanism 30 in synchronism by being fixed to the upper arm of the arms 33, and the arm 15.

In Figures 8 to 14, there is schematically depicted a modified form of the height adjustment mechanism 10 of Figures 1 to 7. In this embodiment there is incorporated a locking device 40. The locking device 40 includes an elongated member 41 which may be provided by a generally rigid rod or alternatively a flexible elongated member such as a cable. The member 41 has its upper extremity fixed to the base 13 by means of a bracket 42. The bracket 42 has an elongated slot 43 along which the elongated member 41 may slide. The upper end of elongated member 41 is provided with a head 44 which cannot pass through the slot 43, while below the bracket 42, there is a clip 45 which cooperates with the head 44 to retain the elongated member 41 captively located with respect to the bracket 42.

Attached to the support member 14 is a clamp assembly 46. The clamp assembly 46 includes a clamp member 47 which extends to a handle 48. The clamp member 47 has a slot 49 through which the elongated member 41 passes. When the end part 50 of the clamp member 47 is generally perpendicular to the elongated member 41 (as seen in Figure 14) the clamp assembly 46, and therefore the bench part 12, can move for the [N:\LIB1'n00297:DSS 6 purposes of height adjustment of the bench part 12. When the end portion 50 is inclined to the elongated member 41, as shown in Figure 13, the clamp assembly 46 is prevented from moving downward and therefore the bench part 12 is prevented from moving downward. However, the clamp assembly 46 does not prevent upward adjustment in this 5 configuration.

The clamp member 47 passes through a bracket 51 by means of an aperture 52. In movement of the clamp member 47, it generally pivots about an axis defined by the aperture 52. A spring 53 extends between a flange 54 and the end portion 50, to move the end portion 50 to the clamp position shown in Figure 13. The flange 54 has an aperture 55 through which the elongated member 41 moves. - As the bench part 12 moves downward, the elongated member 41 is caused to move horizontal and therefore move along the slot 43. To aid in maintaining the elongated member 41 vertically oriented, a further flange 56 is provided with the elongated member 41 passing through an aperture 57 in the flange 56.

In the above described preferred embodiment, an operator grips the handle 48 and pivots the handle 48 in the direction of the arrow 58. This then moves the end portion 50 to the position basically shown in Figure 14 permitting lowering of the bench part 12.

In the above described embodiment, the position of the bench part 12 is determined at what position the end portion 50 engages the elongated member 41.

In the above described embodiments, the locking devices 19 and 46 prevent downward movement of the bench part 12 until the associated handle 24 or 48 is moved. The locking devices 19 and 46 do not prevent upward movement of the bench part 12.

In Figure 15, there is schematically depicted a locking device 60. The locking device 60 includes an elongated member 61 which could be a rod or cable. It could replace the rod 20 of Figures 3 and 4 or the elongated member 41 of Figures 8 and 9. Engaging the elongated member 61 is a pair of clamp members 62 and 63 provided with apertures 64 through which the elongated member 61 passes. The clamp members 61 and 62 are pivotally supported by a flange 65 having apertures 66 through which the clamp [N:\LIBTI100297:DSS 7 members 62 and 63 pass and which basically define the axes about which the members 62 and 63 pivot.

Linkages 67 are pivotally attached to the extremities of the members 62 and 63 and extend to a common pivot 68. By movement of the pivot 68 in the direction of the arrow 69, the clamp members 62 and 63 are moved to a position generally perpendicular to the elongated member 61 so as to release the member 6 1. A spring 70 would move the members 61 and 62 to the clamp position shown in Figure 15. In this embodiment, a handle would cause movement of the pivot 68 to release the member 61. By providing the two clamp members 62 and 63, the bench part 12 would be prevented from upward lo and downward movement until the pivot 68 was moved as discussed. When the pivot 68 moves in the direction of the arrow 69, the members 62 and 63 pivot in the direction of the arrows 71.

In Figures 16 to 18 there is schematically depicted a height adjustment 80, which mechanism 80 is a modification of the mechanisms previously described.

The mechanism 80 includes a base 81 and a support 82. Extending between the base 81 and support 82 is a pair of generally parallel arms 83 which are pivotally attached adjacent their ends, by pivot assemblies 98 and 99, to the base 81 and support 82.

In this embodiment the arms 83 are generally co-extensive and the same length. Also each pivot assembly 98 is spaced by the same fixed distance from its associated pivot assembly 99. Accordingly in this configuration the support 82 can be moved without altering its orientation. However it should be appreciated the arnis 83 could have different lengths and the pivot assemblies 98 and 99 varied in spacing so that as the support 82 moved, its orientation changed. Still further the arms 83 need not be parallel if the orientation of the support 82 is not to be maintained.

The support 82 is height adjustable by operation of the locking or clamping device 84. The device 84 includes an elongated member in the form of a rod 85 which is selectively engaged by a clamp member 86. The rod 85 is inclined to the arms 83. In this embodiment the member 86 is a plate or strip having an aperture 87 through which the rod 85 passes.

[N:\LIBTI]00297:DSS 8 Pivotably mounted on the support 82 is a handle 88, which in this embodiment is a rod having an elongated part 89 and an end part 90 generally normal to the part 89. The other extremity of the handle 88 has a knob 91. The handle 88 is pivotable about a generally vertical axis generally normal to the part 89 to operate the device 84.

The member 86 is engaged by the end part 90 to cause movement of the member 86 relative to the rod 85. More particularly the plain of the aperture 87 is moved in inclination to the longitudinal axis of the rod 85. When the plain of the aperture 87 (that is the member 86) is moved toward or to a portion generally normal to the rod 85 (as shown in Figure 16) the rod 85 is free to move. Accordingly the member 86 is movable lo between a clamp position (Figure 18) engaging the rod 85 and preventing movement thereof, and a release position (Figure 16) in which the rod 85 is free to slide through the aperture 87 to adjust the height of the support 82 relative to the base 81.

The member 86 pivots about a pin 92 to alter the inclination of the member 86 relative to the rod 85. The member 86 is urged to the clamp position by a spring 93 is which extends between the flange 94 fixed to the support 82, and the member 86. The spring 93 is "wound" around the rod 85.

The rod 85 is pivotally attached at one end to the base 81 by a pivot assembly 104 and is selectively fixed to the support 82 by the locking device 84. When the member 86 engages the rod 85 and prevents movement thereof, the arms 83 are not free to move.

When the member 86 releases the rod 85, the arms 83 are free to move to thereby enable height adjustment of the support 82 relative to the base 81.

The end part 90 projects through a slot 95 in the support 82 to enable engagement with the member 86.

If so required the locking device 84 can be enclosed in a cover 96, of which the flange 94 can form part.

In operation of the above mechanism 100, the operator grips the knob 91 and moves it in the direction of the arrow 96 to release the rod 85. When the knob 91 is released, the rod 85 is again engaged under the action of the spring 93 on the member 86.

[N:\LIBTI100297:DSS 9 It should be appreciated that downward pressure on the support 82 increases the clamping grip the member 86 has on the rod 85 as the rod 85 will urge the member 86 to tilt further in the direction of the arrow 97, tilting the aperture 87 further from the release position.

The handle 88 is urged to a position releasing the member 86 by a spring 100. The spring 100 has a center part 101 wound about a pin 105, and two legs 102 and 103. The leg 102 engages the support 82 while the leg 103 engages the handle 88 to pivot the handle 88 to release the member 86.

It should further be appreciated that the rod 85 could be pivotally attached to the lo support 82 and the locking device 84 mounted on the base 81,.

In the above embodiment the support 82 is always free for upward movement relative to the base 81, and that the locking device 84 only prevents downward movement of the support 82. This is because upward movement of the support 82 will move the rod 85 to cause tilting of the member 86 to its release position.

As a further modification the rod 85 could be pivotally attached to either arm 83, at a position remote from the locking device 84, provided there was relative movement between the locking device 84 and the rod 85 when the support 82 was moved relative to the base 81.

[N:\LIBT1100297:DSS

Claims

Claims:

1. A height adjustment mechanism for a work surface, said mechanism comprising:

a base; a pair of arms each having opposite end portions and pivotally attached at adjacent end portions to said base, said arms being adapted for pivoting movement about respective first parallel pivot axes, which first pivot axes are generally parallel and generally transverse of the longitudinal direction of extension of the arms; a support member pivotally attached to end portions of said arms remote from said 1 o base, the remote end portions being pivotally attached to said support member for pivoting movement relative thereto about second parallel pivot axes, which second axes are generally transverse of the general direction of extension of the arms; and locking means operable to prevent pivoting of said arms in a predetermined direction relative to said base, said locking means comprising an elongated member and a clamp member to engage said elongated member, said clamp member and elongated member being arranged so that pivoting of said arms cause relative displacement between the clamp member and elongated member along said elongated member so that the displacement of the support member with respect to the base is determined by the position at which the clamp member engages the elongated member.

2. The mechanism of claim 1 wherein said elongated member is a rod and said clamp member has an aperture through which the rod passes, and wherein said clamp member tilts relative to said rod between a release position and a clamp position.

3. The mechanism of claim 2 wherein aperture lines in a plain, with said plain being moved toward a position normal to said rod when said member is moved to said release position.

4. The mechanism of claim 3 further includes a clamp spring means urging said clamp member to said clamp position, and said mechanism further includes a handle manipulated by a user to move the clamp member to the release position.

[N:\LIBTTI00297:DSS 11

5. The mechanism of claim 3 or 4 wherein the locking means is mounted on the support, and the rod is pivotally attached to the base and extends therefrom to the locking means.

6. The mechanism of claim 3 or 4 wherein said rod extends from said base and said locking means is mounted on said support.

7. The mechanism of claim 4 wherein the locking means is mounted on the support, said rod is pivotally attached to said base, and said handle is pivoted to cause movement of said clamp member to the release position.

8. The mechanism of claim 7 wherein said clamp member is fixed to said handle.

9. The mechanism of claim 7 wherein said clamp member is pivotally mounted on said support, and said handle is also pivotally on said support.

10. The mechanism of claim 9 further including a handle spring means urging said handle to move to a position allowing said clamp member to move to the clamp position.

11. The mechanism of claim 10 wherein said clamp spring means is a spring wound around said rod.

12. The mechanism of claim 11 wherein said locking device includes a position against which said clamp member abuts and about which said member pivots to tilt relative to said rod.

13. The mechanisms of claim 3 or 4, wherein there are two claim members, a first one of said clamp members being operable to prevent movement of said support in said predetermined direction, and a second one of said clamp members being operable to prevent movement of said support in a direction opposite to said predetermined direction.

14. A height adjustment mechanism substantially as herein before described with reference to Figures 1 to 7, Figures 8 to 14, Figure 15, or Figures 16 to 18.

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