GB2591807A

GB2591807A - A furniture platform lifting mechanism

Info

Publication number: GB2591807A
Application number: GB2001728.1A
Authority: GB
Inventors: Robertson Dale; Brown Paul
Original assignee: Eevolv Ltd
Current assignee: Eevolv Ltd
Priority date: 2020-02-07
Filing date: 2020-02-07
Publication date: 2021-08-11
Anticipated expiration: 2040-02-07
Also published as: GB2591807B; GB202001728D0

Abstract

The furniture platform lifting mechanism 10 has a base 12, first and second connecting arms 14, 16 with complimentarily engaging guide 20 and follower, and an actuator 30 moving the mechanism 10 between a lowered and raised condition by moving the arms 14, 16 and an associated platform relative to the base while maintaining the guide 20 and follower connection. The arms 14, 16 may be releasably engageable with the base 12 and associated platform. The actuator 30 may cause the follower to lift and rotate the associated platform relative to the base 12. An end of the second arm 16 may move freely against the base 12 or associated platform. The guide 20 may include an arcuate or linear section and may be groove, and the follower may be a bearing or roller. The mechanism 10 may be used as part of an adjustable chair or with a desk top.

Description

A FURNITURE PLATFORM LIFTING MECHANISM

The present invention relates to a furniture platform lifting mechanism, in particular to a lifting mechanism which can be incorporated into an article of furniture such as a chair or an adjustable chair so as to give that chair lift functionality.

Known articles of furniture such as adjustable chairs include support sections such as a seat support, back support, neck support, and foot support which can be adjusted, either individually or in combination, to enable the occupant of the chair to achieve a comfortable sitting position.

Some occupants have difficulty moving from the sitting position to a standing position when exiting the chair. This difficulty has been alleviated by providing the chair with an integrated lifting mechanism which can lift the entire chair, or the seat section of the chair to gradually raise and tilt the seat section to assist the occupant moving from the sitting to the standing position. Chairs incorporating such a lifting mechanism are referred to as lift chairs or lift recliners.

Known lift chair chairs typically incorporate multi-linkage lifting mechanisms which are complex, requiring many components, and are therefore heavy. Furthermore, such multi-linkage lifting mechanisms occupy a significant amount of space between the seat section of the chair and a base of the chair, the base either directly sitting on the floor or indirectly via legs attached to the base. On chairs with legs, which are becoming increasingly favoured, particularly high legs, the space occupied by the lifting mechanism restricts the height of the legs which can be used. Indeed, on most lift chairs, it is not possible to add legs since the lifting mechanism would be visible from the floor level to the seat section, as well as physically exposing the potentially dangerous mechanism. In these lift chairs, a full height arm side panel is required to cover the lifting mechanism.

There is a need therefore for a chair lifting mechanism which is less complex and lighter than known lifting mechanisms to directly reduce component cost, and indirectly reduce storage, transportation, shipping, distribution and delivery costs.

There is a further need for a more compact lifting mechanism which would occupy less space and give more freedom to the chair designer to use high leg designs on lift chairs which has not been possible, despite the increasing desire to use of high leg designs on non-adjustable and recline-only chairs. The additional space under the lifting mechanism further allows easier access to cleaning tools and machines, as well as access to robotic vacuuming machines which are increasing in popularity.

There is also a need for a lifting mechanism which can be easily incorporated into adjustable chairs and fixed non-adjusting chairs without any lifting functionality to convert the chair to a lift chair and provide that functionality to occupants having difficulty moving from the sitting position to a standing position when exiting the chair. This has the clear sustainability advantage that functioning chairs can be adapted rather than replaced if the occupant requires the lift function.

Thus, according to the present invention there is provided a furniture platform lifting mechanism comprising a base, a first connecting arm, a second connecting arm, and actuator means, in which the first connecting arm has one of a guide or a follower positioned thereon, and the second connecting arm has the other of a guide or a follower positioned thereon, in which actuation of the actuator means between a lowered position of the mechanism and a raised position of the mechanism causes the follower to move relative to the guide to move the first and second connecting arms and an associated platform with which the first and second connecting arms cooperate, relative to the base.

Advantageously, the lifting mechanism is less complex than known lifting mechanisms, and can therefore be easily retro-fitted to an existing article of furniture such as an adjustable chair by mechanically incorporating the first and second connecting arms into the furniture structure, for example, the seat support platform and the chair base of the furniture structure to provide the existing article of furniture with the lifting functionality.

Preferably, the platform of the article of furniture is simultaneously rotated and lifted by the actuator, although non-simultaneous movement is envisaged where the rotation and lifting movement is distinct and achieved by appropriate design of the guide profile. Advantageously the movement of the platform relative to the base can be controlled by the design of the guide profile to provide a comfortable transition as the chair moves between a lowered position corresponding to a sitting position of the occupant, to a raised position corresponding to a standing position of the occupant.

In one embodiment, the article of furniture is an adjustable chair, with the first connecting arm pivotally connected to the base and the seat support section, and the second connecting arm pivotally connected to the seat support section and having an engagement means which is engaged with and moveable relative to the platform.

In further embodiments, the article of furniture need not be limited to a desk top or a chair, and can be any article of furniture where it is advantageous to the occupant or the user of the furniture to lift a platform or other part of the furniture relative to the base upon which the platform or part of the furniture is supported.

The invention will now be described by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a furniture assembly including an article of furniture and a furniture platform lifting mechanism according to the present invention, Figure 2 is a perspective view of part of the furniture assembly of Figure 1, Figure 3 is a perspective view of the furniture assembly of Figure 1 with the guide removed to show the follower, Figure 4 is a perspective view of part of the lifting mechanism of Figure 1, Figure 5 is an enlarged perspective view of part of furniture assembly of Figure 1, Figure 6 is an perspective view of the furniture assembly of Figure 1, Figure 7 is a perspective view of the lifting mechanism of Figure 1, Figures 8 to 10 are enlarged perspective views of part of the lifting mechanism of Figure 1, Figure 11 is a perspective view of part of the lifting mechanism of Figure 1 with the second connecting arm removed to show the bearing, Figure 12 is a perspective view of the lifting mechanism of Figure 1, Figure 13 is an enlarged perspective view of part of the lifting mechanism of Figure 1, Figure 14 is an enlarged perspective view of a part of an alternative lifting mechanism, Figure 15 is a perspective view of an alternative lifting mechanism, Figures 16 to 18 are perspective views of the lifting mechanism of Figure 1 in the lowered, intermediate and raised positions, and Figures 19 and 19 are perspective views of an alternative article of furniture.

In Figures 1 to 13, a furniture assembly 80 comprises an article of furniture in the form of an adjustable chair 50 and a furniture platform lifting mechanism in the form of a chair lifting mechanism 10.

The chair 50 includes a platform in the form of a seat support section 52 and side panels 54 (only one of which is shown in Figure 1) an adjustable back support section (not shown), and an adjustable foot support section 58. It will be understood that the chair need not be limited to an adjustable chair, nor to a chair with the support sections described, nor to the mechanisms employed to adjust the support sections. It will be further understood that for an adjustable chair, further adjustable support sections are envisaged.

As will become apparent, the furniture platform lifting mechanism of the present invention can be used with any article of furniture where lifting functionality is required, irrespective of whether the article of furniture includes adjustable sections (fixed non-adjusting chairs), or where the article of furniture includes adjustable sections, irrespective of the mechanism used to adjust those sections of the furniture.

The chair lifting mechanism 10 include a base 12, a pair of spaced parallel first connecting arms 14, a pair of spaced parallel second connecting arms 16, and actuator means 30. Whilst a pair of connecting arms are used in this embodiment, single first and second connecting arms are also envisaged to provide the relative movement between the seat support section and the base.

The base 12 includes four identical legs 56 which are releasably secured thereto. It will be appreciated that the legs 56 can be supplied already secured to the base of the chair lifting mechanism 10, or, if the chair already includes legs, the legs can be removed from the chair and secured to the chair lifting mechanism, this being achievable by employing the same securing arrangement on the chair lifting mechanism as used to secure the legs to the chair.

The first connecting arm 14 has a first connection point 24 and a second connection point 26. The first connecting arm 14 is rotatably or pivotally mounted to a downwardly extending limb 53 of the seat support section 52 using a bearing assembly 25 which is secured inside a crimped portion 29 of the first connecting arm 14 (Figure 2).

The first connecting arm 14 is rotatably or pivotally mounted to the base 12 at the second connection point 26 using a bearing assembly 27 which is identical to bearing assembly 25 which is secured inside a crimped portion 31 of the first connecting arm 14 (Figure 4).

The second connecting arm 16 is rotatably or pivotally mounted to the base 12 at a third connection point 32 using a bearing assembly 33 which is identical to bearing assembly 25,27 and is secured inside a crimped portion 35 of the second connecting arm 16.

An engagement means in the form of roller or wheel 28 is provided on a free end 39 of the second connecting arm 16. The roller 28 includes a radially extending portion 41 to prevent inward lateral movement of the roller 28 relative to the seat support section 52 (Figure 10).

The chair lifting mechanism 10 further comprises a downwardly extending guide 20 positioned pad-way along and secured to the first connecting arm 14 between the first 24 and second 26 connections points The guide 20 is in the form of a groove and includes an arcuate section 43 and a linear section 41 (Figure 9).

The chair lifting mechanism 10 further comprises a follower in the form of a bearing 22 positioned part-way along and secured to the second connecting arm 16 between the third connection point 32 and the free end 39.

A cross-member 36 connects each one of the first connecting arms 14 to each other to create an H-frame type structure. It will be understood that whilst the cross-member 36 and each connecting arm are connected at a connection point positioned between the bearing 22 and the third connection point 32, the connection point need not be so limited. In fact, the first connecting arms could extend beyond the connection on the base and the actuator could be run in the opposite direction to move the connecting arm.

The actuator 30 has a first end 38 connected to the cross-member 36 and a second end 40 connected to a cross-member 42 of the base 12 The actuator 30 is a linear push only actuator having a first end 38 (motor and gear box end) pivotally mounted to the cross-member 36 and a second end (rod) 40 pivotally connected to a bracket secured to the cross-member 42.

The chair lifting mechanism 10 further comprises a plastic retaining means 90 which is securely positioned on the free end 39 of the second connecting arm 16. The retaining means 90 includes an outwardly laterally extending projection 92 which cooperates with a laterally inwardly extending ledge 13 of the seat support section 52.

The ledge 13 is sandwiched between the engagement means 28 and the projection 92 to substantially retain the seat support section 52 on the second connecting arm 16. This is important as it prevents the seat support section from over rotating, and potentially becoming detached from the chair lifting mechanism, which could be dangerous for the occupant of the chair.

In an alternative embodiment, the lifting mechanism 110 includes a retaining means in the form of a strap 190 connected to both the base 112 and seat support section 152 to substantially retain the seat support section 152 on the second connecting arm 116 (Figure 15).

In a further alternative embodiment, the retaining means is provided on the seat support section 252 rather than being part of the chair lifting mechanism 210. The chair lifting mechanism 210 is identical to the chair lifting mechanism 10 except for the removal of the retaining means. The seat support section 252 includes a channel 254 within which the engagement means 228 locates. It should be noted that engagement means 228 differs from engagement means 28 in that a rolling bearing is used to move in the channel 254 rather than the engagement means 28 which includes a radially extending portion 41. The rolling bearing 228 is substantially retained within the channel 254 and therefore the seat support section 252 is retained on the second connecting arm 16 to prevent over rotation (Figure 14).

Operation of the chair lifting mechanism 10 is as follows: Figure 16 shows the chair lifting mechanism 10 incorporated into an adjustable chair 50 in a lowered (sitting) position.

Actuation of the actuator means 30 from a lowered position (Figure 16) of the chair lifting mechanism towards an intermediate (Figure 17) and then raised (Figure 18) position causes the engagement means 28 of the second connection arm 16 to cooperate, specifically, to engage with and move freely against the underside of the seat support section 52 of the chair 50, and the follower 22 of the second connection arm 16 to move within the guide 20 of the first connecting arm 50 to simultaneously lift and rotate the seat support section 52 relative to the base 12. Specifically, the relative movement between the follower 22 and the guide 20 causes rotation of the seat support section 52 about the first connection point 24 as the seat support section 52 is raised by being acted upon by the engagement means 28. This rotation and lifting movement is emphasised by the second connection point 24 and the engagement means 28 moving towards each other as the actuator means moves from the lowered position to the raised position.

It will be understood that as the seat support section 52 is lifted and rotated relative to the base 14, the retaining means 90 prevents the seat support section 53 from over rotating. As described above, alternative retaining means in the form of strap 190, or modification of the seat support section to include a channel 254 prevents the seat support section 53 from over rotating as it moves from the lowered towards the raised position.

In Figures 19 and 20, an alternative furniture assembly 350 comprises a desk top 380 and a desk top lifting mechanism 310. The desk top lifting mechanism 310 is identical to chair lifting mechanism 210, relying on the inclusion of modified desk top support section 352 to prevent over rotation of the desk top 350. Operation of the desk top lifting mechanism 310 is identical to the chair lifting mechanism 210 as the desk top moves from a lowered (not shown) towards an intermediate position (Figure 19) and then raised position (Figure 20).

Claims

CLAIMS1 A furniture platform lifting mechanism (10) comprising a base (12), a first connecting arm (14), a second connecting arm (16), and actuator means (30), in which the first connecting arm (14) has one of a guide (20) or a follower positioned thereon, and the second connecting arm (16) has the other of a guide or a follower (22) positioned thereon, in which actuation of the actuator means (30) between a lowered position of the mechanism and a raised position of the mechanism causes the follower (22) to move relative to the guide (20) to move the first (14) and second (16) connecting arms and an associated platform (52) with which the first (14) and second (16) connecting arms cooperate, relative to the base (12).
2 A furniture platform lifting mechanism (10) according to claim 1 in which the first connecting arm (14) is releasably engageable with the base (12) and an associated platform (52) and the second connecting arm (16) is releasably engageable with the base (12) and the associated platform (52).
3. A furniture platform lifting mechanism (10) according to claim 1 or 2 in which actuation of the actuator means (30) causes the follower (22) to lift and rotate the platform (52) relative to the base (12).
4. A furniture platform lifting mechanism (10) according to claim 3 in which actuation of the actuator means (30) causes the follower (22) to simultaneously lift and rotate the platform (52) relative to the base (12).
A furniture platform lifting mechanism (10) according to any preceding claim in which the first connecting arm is releasably connectable to the base and the platform and the second connecting arm is releasably connectable with one of the base and the platform and releasably engageable with the other of base and the platform.
6 A furniture platform according to claim 5 in which the second connecting arm is releasably engageable to move freely relative to the other of base and the platform.
7. A furniture platform according to claim 6 in which the second connecting arm is releasably engageable to move freely against the other of base and the platform.
8 A furniture platform lifting mechanism (10) according to claim 7 in which the second connecting arm is engageable with and freely moveable relative to the platform (52) and pivotally connected to the base (12).
9 A furniture platform lifting mechanism (10) according to any one of claims 2 to 8, the first connecting arm (14) having a first connection point (24) and a second connection point, the first connection point (22) being pivotally connected to the base (12), the second connection point (24) being pivotally connected to an associated platform (52), the second connecting arm (16) having a third connection point (26) and an engagement means (28), the third connection point (26) being pivotally connected to one of the base (12) or the associated platform (52), the engagement means (28) engageable with and freely moveable relative to the other of the base (12) or the associated platform (52), in which actuation of the actuator means (28) from a lowered position of the mechanism to a raised position of the mechanism causes the engagement means (28) to move freely relative to the base (52) or the associated platform (52), and the follower (22) to move relative to the guide (20) to move the platform (52) relative to the base (12).
10.A furniture platform lifting mechanism (10) according to any preceding claim in which actuation of the actuator means (30) between the lowered position and the raised position causes the follower (22) to move within the guide (20) to rotate the platform (52) about the first connection point (24)
11.A furniture platform lifting mechanism (10) according to any preceding claim in which actuation of the actuator means (30) from the lowered position to the raised position causes the second connection point (24) and the engagement means (28) to move towards each other.
12.A furniture platform lifting mechanism (10) according to any preceding claim in which the guide (20) includes an arcuate section (43).
13.A furniture platform lifting mechanism (10) according to claim 12 in which the guide (20) includes a linear section (45).
14.A furniture platform lifting mechanism (10) according to any preceding claim in which the guide (20) is a groove, and/or the follower (22) is a bearing.
15.A furniture platform lifting mechanism (10) according to any preceding claim in which the engagement means (28) is a roller.
16.A furniture platform lifting mechanism (10) according to any preceding claim in which the engagement means (28) is positioned at a free end of the second connecting means (18).
17.A furniture platform lifting mechanism (10) according to any preceding claim in which actuator (30) has a first end connected to the base, and second end connected to the first connecting arm (14).
18.A furniture platform lifting mechanism (10) according to any preceding claim in which the first connecting arm is a pair of spaced first connecting arms, and the second connecting arm is a pair of spaced second connecting arms.
19.A furniture platform lifting mechanism (10) according to claim 18 in which the pair of spaced first connecting arms are connected by a cross member (31), and the actuator (30) is connected to the cross-member.
20.A furniture platform lifting mechanism (10) according to any preceding claim further comprising retaining means (90) to substantially retain the platform (52) in contact with the engagement means (28) during movement between the raised and lowered positions.
21.A furniture platform lifting mechanism (10) according to claim 20 in which the retaining means (90) includes a projection (92), the platform includes a ledge (13) which is sandwiched between the engagement means (28) and the projection (92) to substantially retain the platform (52) in contact with the engagement means (28) during movement between the raised and lowered positions.
22.A furniture platform lifting mechanism (110) according to claim 20 in which the retaining means is a strap (190) connected to both the base (12) and the platform (52).
23.A furniture assembly (80) comprising a furniture platform lifting mechanism (10) according to any preceding claim and an article of furniture (50).
24.A furniture assembly (80) according to claim 23 in which the article of furniture is an adjustable chair (80) and the platform is a seat support section (52).
25.A furniture assembly (380) according to claim 23 in which the article of furniture is a desk top (350) and the platform is a desk top support section (352).
26.A furniture assembly (280) according to claim any one of claims 23 to 25 when dependent on any one of claims 1 to 19 in which the platform includes a channel (254) which defines a retaining means to substantially retain the platform (252) in contact with the engagement means (228) during movement between the raised and lowered positions.