AU601055B2 - Support platform - Google Patents

Description

1 -r i COMMONWEALTH OF AUSTRALIA FORM PATENTS ACT 1952 COMPLETE S P E C IF I CAT IO N FOR OFFICE USE: S.ss3 Int.Class Application Number: Lodged: Complete Specification Lodged: o o Accepted: S ca Published: o o riority: e000 o" 0 OP elated Art: 00 a r' ;S C Name of Applicant: 0 O0 0 00 o°o Pddress of Applicant: 00 0A l Actual Inventor: HOOD COMPUTERS PTY. LIMITED 56 Bath Road, KIRRAWEE, New South Wales, 2232, Australia VICTOR ANTHONY PECK 2-"Address for Service: S-H-I-IrSSPEN-WAR.S-5S5--C-l-arence-S-t-reet, Sydney 0 9 00000 C omplete Specification for the Invention entitled: "SUPPORT PLATFORM" The following statement is a full description of this invention, including the best method of performing it known to me/us:- Complete of PI3133 dated 16th July, 1987 SOOC'942 13/07/8:3 1 r i _i .i i l'i

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This invention relates to support platforms of the type used for word processor terminals, computer

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terminals, typewriters and similar devices. More 1 particularly, the invention relates to support platforms having a first support surface and a second support surface height adjustable with respect to the first.

The second support surface is normally used to support a keyboard which can be height adjusted to suit o the operator. This not only increases operator's comfort 090 fI I0 but also is thought to lessen the likelihood of the 0o, operator suffering repetitive strain injury. The first o ft S,.l support surface of the platform is used to support the body of the device, usually including a video display, which does not require height adjustment.

Known support platforms of this type provide for 4 height adjustment of the second support surface by operating a releasable locking mechanism with one hand and simultaneously adjusting the support to the required i height with the other. When the required height is SI0 'a attained the locking mechanism is manipulated to lock the support in position. The need for two hands to adjust the prior art support platforms makes adjustment inconvenient and cumbersome.

It is an object of this invention to provide a 4 o. support platform which will overcome, or at least ameliorae, the above disadvantage. i Accordingly, this invention consists in aksupport platform comprising Ja first support surface and a second -2- I t support surface height adjustable with respect to the first, said hinge I comprising first and second parallel arms of substantially equal length,

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each pivotally connected each end respectively with the first and second support surfaces. The hinge includes a single selectively releasable locking mechanism comprising a portion of the first arm which is releasably engaged by detent means to prevent pivotal movement of the first arm and lock the hinge. The locking mechanism is operable while grasping a I marginal edge of the second surface to allow single handed adjustment thereof.

The hinge means preferably includes resilient biasing acting between the pivotal connection of one arm and a point intermediate the pivotal connections of the other arm so as to act against the downward force imposed by the weight of the second support surface.

One embodiment of this invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a schematic perspective view showing the relevant portions of a support platform according to this invention; Figure 2 is a view in the direction 2-2 of Figure 1; I3 :1 4 I: i

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id -3rhk/0092E 5 R .li- i -u ~ilf LFli~ and Figure 3 is a part section along the line 3-3 of Figure i.

As shown in Figures 1 to 3 a support platform comprises a first planar support surface 11 and a second planar support surface 12 which is height adjustable with respect to the first. Surface 11 can form part of a desk (not shown) and can be supported in the conventional manner by legs or the like (not shown). Surface 11 can also be supported by attachment to a wall (not shown) for example.

Two hinge arrangements 13, 14 comprise hinge means which maintain surface 11 and surface 12 substantially parallel at each height of surface 12. The hinge arrangements 13, 14 are generally similar each including two right angle brackets 15, 15A, 16, 16A respectively fastened to surfaces 11 and 12 by screws 17. Each hinge 13, 14 has a pair of parallel arms 18, 18A, 19, 19A of substantially equal length.

d0 The upper arms 18, 18A are rigidly interconnected by 'i a rectangular hollow section (RHS) 20 joined to the mid points of the arms for example by electric arc welding.

The arms 18, 19A are pivotally connected adjacent each end by means of bolts at 21, 21A and 22, 22A respectively to the surfaces 11 and 12 via the corresponding right angle brackets. Similarly, lower arms 19, 19A are pivotally connected adjacent each end by means of bolts at 23, 23A and 24, 24A.

-4- L 77 An extension spring 25 is connected between pivotal connection 21 and a point between the pivotal connections of arm 19 to provide resilient biasing acting against the downward forward imposed on hinge 13 by the weight of surface 12. In this way the effort required to adjust the height of surface is lessened.

The distances between pivots 21, 21A and 22, 22A is equal to the distances between pivots 23, 23A and 24, 0 24A. Further the distances between 21, 21A and 23, 23A 0 is equal to that between 22, 22A and 24, 24A. It will 0 4 o therefore be apparent that the hinges 13, 14 form a 0000 o0 parallelogram which results in surfaces 11 and 12 being 0.

kept parallel at each height of surface 12.

A single selectively operable locking mechanism is o' associated with hinge 13. The mechanism takes the form o #4 14 of a toothed extension 26 of arm 18 which projects beyond 0, pivotal connection 22 and into which a correspondingly toothed member 27 is releaseably engaged. Extension 26 is kept in alignment by means of a pin 28 which projects 00 04r into guiding groove 29. Toothed member 27 is mounted the end of a shaft 30 mounted for longitudinal movement in a guide 31 affixed to bracket 16 for example by welding. A handle 32 is formed on the other end of shaft 30 and a compression spring 33 contained within guide 31 biases the shaft 30 in a direction to maintain engagement of member 27 with toothed extension 26. The member 27 is disengaged from toothed extension 25 by pulling on handle 32. When handle 33 is released member 27 is urged into ~ji~ ii l*~rr- VI engagement with extension 25 by spring 33. It will be apparent that toothed member 27 comprises detent means since engagement of the member prevents pivotal movement of arm 18. This locks the hinge 13 and retains surface 12 at the selected height.

Handle 32 is positioned adjacent a marginal edge of surface 12 so that the handle and edge can be simultaneously grasped with one hand. Thus to adjust the i height of surface 12 the marginal edge of the surface is ann 0 grasped and two fingers hooked around handle 32. The o handle is pulled toward the edge thus releasing member 27 and unlocking the hinge 13. Surface 12 is then moved to °O the required height using the same hand and handle 32 is released to lock the hinge 13 at the new height.

oo+ In this way the support platform of this invention o provides for simple single handed height adjustment Df o second support surface 12.

0 a t The foregoing describes only one embodiment of this invention and modifications may be made thereto without eo o o 20 departing from the scope of the invention. For example, C 0 any number of hinges 14 which do not include a locking mechanism can be provided as required.

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Claims (4)

1. A hinge for a support platform having a first support surface and a second support surface height adjustable with respect to the first; said hinge comprising first and second parallel arms of [i substantially equal length, each pivotally connected adjacent each end Srespectively with the first and second support surfaces; said hinge including a single selectively releasable locking mechanism comprising a portion of said first arm which is releasably engaged by detent means to prevent pivotal movement of the first arm, and lock the hinge; and whereby said locking mechanism is operable whilst grasping a marginal edge of said second surface to allow single handed height adjustment thereof.

2. A hinge as claimed in claim 1 wherein said portion further comprises two or more projections and said detent means comprises a correspondingly configured member adapted to releasably engage said projections.

3. A hinge as claimed in either of claims 1 or 2 wherein said hinge means include resilient biasing acting between the pivotal connection of one of said arms and a point intermediate the pivotal connections of the other arm so as to act against the downward force imposed.

4. A support pltformas claimed in any of claims 1-3 wherein the detent means further comprises a shaft mounted for longitudinal movement in j a guide; the guide containing a detent biasing means which urges the shaft to maintain engagement of the detent means with said extension; and a handle adjacent the second surface and affixed to the shaft for longitudinally displacing the shaft against the bias of said detent biasing means. 7 rhk/O92E A supor G--p tfGisubstantially as herein described with reference to Figures 1 to 3 of the accompanying drawings. DATED this FIRST day of MAY 1990 Hood Computers Pty. Limited Patent Attorneys for the Applicant SPRUSON FERGUSON -8- rhk/0092E