Adjusting And Locking Mechanism For Adjustable And Collapsible Table

Abstract

Mechanism for adjustably connecting and locking in adjusted positions two telescoping tubular members which serve as a single standard for interconnecting a table base and a vertically adjustable weight-biased table top, in which the telescoping tubular members are connected for their relative adjustment to produce therebetween a frictionally smooth sliding movement restricted to a maintained straight vertical direction, and in which the locking mechanism is structured to require but a small manual effort on the part of the user, yet be able to apply or exert a large force on the tubular members such as to firmly lock the same together.

Description

This invention relates to an adjustable and collapsible table and more particularly to an adjusting and locking mechanism especially adapted for vertically adjusting the tabletop of a collapsible table.

In the adjustable and collapsible table for which the adjusting and locking mechanism of the present invention is especially adapted, a tabletop is joined to, mounted and supported on a table base by means of a single interconnecting standard which is laterally offset and positioned at one side of the table top and base, the adjusting and locking mechanism for the vertical locking adjustment of the tabletop being embodied or incorporated in said interconnecting supporting standard. The said sole supporting standard comprises two relatively adjustable telescoping members, the lower one united to the table base and the upper one connected to and carrying the tabletop.

The vertical adjustment of the tabletop in elevating and lowering the same, is to accommodate various heights to serve different uses such as a typing table, an eating table for normal or bed use, a drawing or reading table and one collapsible for storage use.

For a table of this structure, character and service, the relatively adjustable telescoping members and the adjusting and locking mechanism therefor, should be devised, for optimum effects, so as to accomplish the following purposes and results:

1. The adjusting movement of the upper telescoping member carrying the tabletop should be smooth and in a restricted and maintained straight vertical direction, despite the weight bias exercised thereon by the tabletop, connected as the latter is to the laterally offset position of this telescoping member;

2. The movement of the upper telescoping member in unlocked condition should be a free-sliding one, yet one in which the tabletop and its supporting upper telescoping member will frictionally hold the position to which it has been adjusted, prior to being locked in such position;

3. The locking means should require a small manual effort on the part of the user, yet should be able to exert a large force effective on the upper telescoping member such as to firmly lock the telescoping members together to firmly support the tabletop and such appurtenances as will be placed thereon; and

4. The elements of the locking means should be constructed so that whatever force is applied to the upper telescoping member will not mar or deface the exterior surface thereof, which latter contains a decorative, such as a painted or enameled film, and becomes exposed when the tabletop is moved to an elevated position.

The principal object of our present invention is the provision of an adjusting and locking mechanism and an adjustable and collapsible table embodying the same which are constructed and devised to accomplish these stated purposes and results in optimum fashion.

To the accomplishment of the foregoing object and such other objects as may hereinafter appear, our invention relates to an adjusting and locking mechanism especially designed for an adjustable and collapsible table as more particularly defined in the appended claims and as described in the following specification and shown in the appended drawings in which:

FIG. 1 is a perspective view of an adjustable and collapsible table embodying the adjusting and locking means of the invention for vertically elevating and lowering the tabletop and locking the same in adjusted positions;

FIG. 2 is a perspective view of the same shown in collapsed condition for storage use;

FIG. 3 is an exploded view shown in perspective of the parts of the adjusting and locking mechanism;

FIG. 4 is a view thereof shown in an enlarged scale and taken in cross section in the plane of the line 4--4 of FIG. 1 and showing the parts in a locked position;

FIG. 5 is a view of FIG. 4 taken in cross section in the plane of the line 5--5 of FIG. 4 and showing the parts in an unlocked position; and

FIG. 6 is a perspective view of parts of the locking mechanism taken in cross section in the plane of the line 6--6 of FIG. 5.

Referring now more in detail to the drawings and having reference first to FIGS. 1 and 2 thereof, the adjusting and locking mechanism of the invention is shown applied to an adjustable and collapsible table featured by a tabletop T joined to, mounted and supported on a table base B by means of a single interconnecting standard S which, as shown, is laterally offset and positioned at one side of the table top and base, the adjusting and locking mechanism M designed for the vertical locking adjustment of the tabletop being embodied or incorporated in said single interconnecting supporting standard S.

The supporting standard S comprises two relatively adjustable telescoping members consisting of a lower and outer tubular member 10 united to the table base B and an inner and upper tubular member 12 connected to and carrying the tabletop T. The vertical adjustment of the tabletop in elevating and lowering the same, is to accommodate various heights to serve a variety of uses, such as a typing table, an eating table adjustable for either normal or bed use, a drawing or reading table, the latter as depicted in FIG. 1, and one collapsible for storage use as depicted in FIG. 2. It will be apparent that due to the offset position of the interconnecting standard S, articles placed on the tabletop will apply a weight bias on the telescoping members 10 and 12 of the standard S which normally interferes not only with the adequate support which must be provided by the standard but with an efficient adjustment of the tubular members of the support and a facile locking operation of the same in their various vertically adjusted positions.

To accomplish the desired operations, the tubular telescoping members 10 and 12 of the standard S, and the adjusting and locking mechanism M are structured and devised, as hereinabove stated, to permit an adjusting movement of the upper telescoping member 12 which is smooth and in a straight vertical direction despite the weight bias exercised thereon by the tabletop, a movement which, in addition to being a free-sliding one, is one in which the tabletop will be held or maintained to its adjusted position prior to and in anticipation of being locked in such position, the construction being moreover such that the locking mechanism, while requiring a small manual effort on the part of the user, functions to exert a large force effective on the upper telescoping member such as to firmly lock the telescoping members together to firmly support the tabletop and such appurtenances as will be placed thereon.

The outer and inner tubular members 10 and 12, comprising preferably metallic members, are cross-sectionally dimensioned so that when assembled, they are spaced internally from each other transversely by the space 14 (see particularly FIG. 4); and at the upper end of the outer tubular member, there is provided a bushing 16 located in and occupying (and substantially filling) the space between the said tubular members, as best shown in FIGS. 4 and 5, the said bushing 16 defining a spacer for said tubular members.

The said bushing 16 comprises a sleeve of plastic material suitably capped or headed by a top 18, the interior surface 20 of the sleeve being in contact with the exterior surface 22 of the inner tubular member 12; the bushing sleeve is made of a material such as a linear polyethylene or polypropylene or "Teflon" which is characterized in possessing surface lubricity; whereby in combination there is presented a frictionally smooth surface for enabling the desired frictionally sliding movement of the inner tubular member. The bushing top 18 and a hole 24 formed therein to receive a teat 26 indented in the outer tubular member 10, provide means for restraining longitudinal movement of the bushing in the outer tubular member. The outer surfaces of the bushing sleeve 28 are in contacting engagement with the inner surfaces 30 of the outer tubular member on three sides of the assembly as best shown in FIG. 5 of the drawings, the remaining surface (50) of the sleeve being engaged by an element of the locking means M as will be described more particularly hereinafter. Thereby the said tubular members 10 and 12 are freely, but with a sliding friction fit, relatively adjustable telescopically, one with reference to the other, the said sliding friction fit being moreover such that the tubular members will hold or maintain any position to which they have been adjusted prior to being firmly locked in such position.

The tubular members 10 and 12 are moreover designed so that the relative telescopic adjustment is restricted to or restrained for movement in a vertical direction, this being best accomplished by forming the same with irregular such as rectangular cross-sectional dimensions. The lower end of the inner tubular member 12 has affixed thereto a plug 32, which preferably is provided with a stabilizing extension 32', also made of a plastic material possessing lubricity, the said plug occupying the full space 14 between the tubular members and defining means for frictionally guiding the telescoping movement of the inner tubular member 12 at its lower end and for minimizing or preventing any rocking motion between the tubular members. This plastic plug 32 is held in position by its head 34 and by a hole 36 therein which is received by a teat 38 indented in the bottom of the tubular member 12 as best shown in FIG. 4.

The means for locking the tubular members 10 and 12 in their telescopically adjusted positions, comprises a locking element 40 fixed to the outer tubular member 10 and movable into and out of engagement with the contiguous outer surface of the bushing sleeve 16, the engagement acting to force the bushing sleeve 16 onto the inner tubular member 12 for the locking action and to release the same from the inner tubular member for the unlocking action.

This locking element 40 comprises more specifically a resilient lever integrally fulcrumed at 44 on the outer tubular member (see FIGS. 4 and 6), the said lever being provided with a cup-shaped part 46 terminating in an outer annular edge 48 positioned to engage the contiguous surface 50 of the bushing sleeve. The locking mechanism further comprises a hand-operated member 52 consisting of a screw-threaded part 54 threadedly mounted in a thimble 56, the flange 58 of which is welded onto the outer tubular member at 60, 60 (See FIG. 3), the screw-threaded part 54 being provided at its outer end with an operating knob 62, the inner end thereof being movable into and out of cooperative engagement with the crest or apex 64 of the cup-shaped part 46.

The locking lever 40 is normally resiliently biased to have the annular edge 48 of its cup-shaped part 46 in normal engagement with the surface 50 of the bushing sleeve 16. Thus even when the hand-operated member 52 is in a retracted or unlocking position as shown in FIG. 5, the assembly, namely the inner and outer tubular members, the bushing sleeve and the locking lever have their parts in close contacting relation thereby providing for the free-sliding, but nevertheless frictionally engaging, action of the parts to permit a smooth, lubricated, relatively telescopic movement of the outer and inner tubular members, yet additionally supplying the holding action of the parts in adjusted position before the locking action takes place. In the functioning of the locking mechanism, the hand operation of the knob 62 by the exertion of a small force on the locking lever 40 produces a strong force at the annular edge 48 of the cup 46 effective on the face 50 of the bushing sleeve with the result that the assembled parts of the adjusting and locking mechanism are very securely locked in position. In both the locking and unlocking positions of the locking lever 40, the extensive annular edge 48 of the lever cup 46 is always in contact with the surface 50 of the bushing sleeve, thereby providing for a substantial area of frictional (unlocking) and locking engagement of the surface 50 of the bushing.

The described construction is also one which permits of ready assembly of the parts. Thus, the bushing 16 is first slid up onto the inner tubular member 12 and the plug 32 is then snapped (via the parts 36, 38) into the bottom end of this tubular member. This assembly is then moved into the outer tubular member 10 and the bushing 16 is moved down the inner tubular member and into the outer tubular member, being then snapped (via the parts 24 and 26) into position at the top of the outer tubular member.

The adjustable and collapsible table to which this described mechanism is applied further comprises a tabletop T which is swivelly mounted on a horizontal branch 66 of the upper tubular member 12 and held thereto by a suitable locking element 68; and the base B is made to comprise a horizontal branch 70 integral with the lower tubular member 10 and two supporting bars 72 and 74 serving as legs for the table, these bars being movable from the open positions shown in FIG. 1 to the collapsed positions shown in FIG. 2.

The use and operation of the adjusting and locking mechanism and the adjustable and collapsible table to which it is applied, the functioning and the several advantages thereof will be fully apparent from the above-detailed description thereof. It will be further apparent that changes may be made in the structure thereof without departing from the coverage of the invention defined in the following appended claims.

Claims

We claim:

1. Mechanism for adjustably connecting two telescoping tubular members and for locking the same in adjusted positions, comprising relatively adjustable telescoping outer and inner tubular members, the said tubular members being internally spaced from each other transversely, a bushing located and occupying space between and defining a spacer for said tubular members, the said bushing comprising a sleeve of a plastic material the interior surface of which, in contact with the exterior surface of the inner tubular member, presents a frictionally smooth surface for enabling a sliding movement of said inner tubular member, the said bushing sleeve being attached to the outer tubular member at a region to restrain longitudinal movement thereof in said outer tubular member, whereby the said tubular members are freely, but with a sliding friction fit supplied by said bushing sleeve, relatively adjustable telescopically one with reference to the other, and means for adjustably locking the said tubular members in telescopically adjusted positions, said means comprising a locking element fixed to the outer tubular member, said locking element comprising a resilient lever integrally fulcrumed on the outer tubular member and provided with a cup-shaped part movable into and out of engagement with the outer surface of said bushing sleeve to force the latter onto the inner tubular member for the locking action and release the same from the inner tubular member for the unlocking action, and a hand-operated member mounted on said outer tubular member movable thereon into and out of cooperative engagement with the cup-shaped part of said locking element.

2. The adjusting mechanism of claim 1 in which the bushing sleeve is localized at the upper end of the outer tubular member and in which the lower end of said inner tubular member has affixed thereto a plastic piece also occupying space between said tubular elements and defining means for frictionally guiding the telescoping movement of the inner tubular member at its lower end and for preventing rocking motion between said tubular members.

3. The adjusting mechanism of claim 1 in which the bushing sleeve is made of a plastic material possessing lubricity.

4. The adjusting mechanism of claim 2 in which the plastic bushing sleeve and the plastic piece are each made of a plastic material possessing lubricity.

5. The adjusting mechanism of claim 1, in which the hand-operated member comprises a screw-threaded part cooperating with the cup-shaped part.

6. The adjusting mechanism of claim 1 in which the outer tubular member comprises a standard attached to a table base, and the inner tubular member comprises a sole support carrying a tabletop, the adjusting mechanism defining the means for vertically adjusting the tabletop relatively to said base.

7. The adjusting mechanism of claim 1, in which the outer and inner tubular members are metallic members cross-sectionally shaped to confine the tubular members to only a vertical adjustment.

8. The adjusting mechanism of claim 1 in which the cup-shaped part of the resilient lever is formed with an outer annular edge positioned to engage the contiguous surface of the bushing sleeve to force the latter onto the inner tubular member.

9. The adjusting mechanism of claim 1 in which the cup-shaped part of the resilient member is formed (a) with an outer annular edge positioned for cooperative engagement with the contiguous surface of the bushing sleeve and (b) with an inner apex positioned for cooperative engagement by a screw-threaded part of the hand-operated member.