AU2004205109A1 - A reclining chair with tilting actuator - Google Patents

Description

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Applicant: ARTISTIC HEALTHCARE SEATING PTY LTD Invention Title: A RECLINING CHAIR WITH TILTING ACTUATOR The following statement is a full description of this invention, including the best method of performing it known to us: 2 A RECLINING CHAIR WITH TILTING ACTUATOR The present invention relates to a reclining chair having a tilting actuator for assisting tilting movement in bringing the chair into a reclined position.

Many different types of reclining chairs are available on the market for a range of different purposes.

Driving mechanisms and linkage assemblies used in reclining chairs also differ depending on the desired reclining motion, the desired end position and the means used for effecting tilting movement. These factors are normally dependent on the end purpose of the chair. For example, reclining chairs may be used for relaxing seating in the home, or may be designed as a health chair for sick or elderly people.

One type of reclining chair has an internal mechanism that allows the seat back and base of the chair to tilt back and slightly move rearwardly such that the user is moved into an elevated reclined position. A foot rest connected to the seat by a foot linkage assembly raises as the seat is tilted back in order to support the feet at an elevated comfortable height. To actuate the tilting motion of the reclining chair a lever to one side of the chair connects to the internal mechanism and is partially rotated by the occupier of the chair to slightly lift the base of the seat to a position where the occupier can use his/her weight to carry through with the reclining movement.

The problem with this design is that some people, particularly the elderly and sick, are unable to apply a sufficient force on the lever to initiate the reclining movement. Additionally, since the lever is designed to be operated by the occupier of the chair, people assisting in \\melb_files\home$\shirleyp\specis\P54088 Artistic Healthcare.doc 18/08/04 3 reclining the occupier of a chair, such as nurses, also find it difficult to apply the necessary force.

There is thus a need to provide a reclining chair that can be easily tilted into a reclined position.

SUMMARY OF THE INVENTION In one aspect the invention provides a reclining chair with a tilting actuator for initiating tilting movement, the reclining chair comprising a chair frame, a seat having a base and back, the seat being movable relative to the chair frame between an upright position and a reclined position, and an actuator having an elongate member pivotally linked to the seat base such that actuation the elongate member produces an upward force against the seat base to lift the seat base to a point where a downward force on the seat can complete the tilting movement to bring the seat into a reclined position.

The elongate member is preferably pivotally linked to the seat base by way of a swinging cross bar and linkage member wherein the elongate member, swinging cross bar, linkage member and seat base are all respectively linked by pivotal connections.

The elongate member preferably comprises a hollow push tube containing a lost motion telescopic rod which slides reciprocally within the push tube. Actuation of the elongate member is effected by pushing the push tube and rod combination in a substantially longitudinal direction.

The telescopic rod typically maintains connection with the push tube by way of a return spring that is \\melb_files\home$\shirleyp\specis\P54088 Artistic Healthcare.doc 18/08/04 4 mounted between an internal front end of the rod and an inner rearward wall of the push tube.

The telescopic rod is preferably pinned to the swinging cross bar. The swinging cross bar has an elongate cross section wherein the elongate member is pinned at one end of the elongate cross section and the cross bar is itself pinned to the linkage member at the opposite end of the cross section such that a force imparted by the elongate member will cause the swinging cross bar to rotate against the linkage member and impart a force onto it. The swinging cross bar preferably comprises two hollow bars joined adjacently along their length.

The elongate member is linked to the seat base at a front section of the chair and extends to the rear of the chair from where it may be actuated. The elongate member is preferably actuated by a pedal pivotally connected to a rear end of the push tube and which is accessible from the rear of the chair.

The elongate member, and specifically the push tube, is bent to assist in the most direct and stable transfer of force from the pedal to the swinging cross bar.

The chair includes a brake for controlling the degree of inclination of the seat.

Another aspect of the invention provides a method of reclining a reclining chair having a seat movably supported on a chair frame, the method including: actuating from a rear of the chair an elongate member by applying a force on the elongate member substantially longitudinally of the elongate member, whereby movement of the elongate member produces an upward force on the seat to lift the seat to a point where a downward force on the \\melbfiles\homeS\shirleyp\peci\P54088 Artiatic Healthcare.doc 18/08/04 5 seat can complete the tilting movement to bring the seat into a reclined position.

Brief Description Of The Drawings The present invention is described further by way of example with reference to the accompanying drawings of which: Figure 1 is a side view of a reclining chair in accordance with one embodiment of the present invention; Figure 2 is a schematic side sectional view of a reclining chair in an upright position in accordance with one embodiment of the invention; Figure 3 is a schematic side sectional view of the reclining chair of Figure 2 in a semi-reclined position; Figure 4 is a schematic side sectional view of the recliner chair of Figure 2 in a fully reclined position; Figure 5 is a schematic rear sectional view of the chair; and Figures are side views illustrating components of the reclining mechanism for the reclining chair.

Detailed Description of Preferred Embodiment Figure 1 illustrates in side profile a reclining chair 10 of the present invention with a seat 12 illustrated in ghost lines. As illustrated in the Figures, the chair 10 may be supported on castor wheels 17, or alternatively the chair may be supported stationary on the ground on feet.

\\melb_files\home$\shirleyp\specio\P54088 Artistic Healthcare.doc 18/08/04 6 Figures 2 to 4 illustrate the skeletal, frame components of a reclining chair 10 having a tilting actuator. Figures 2 to 4 further illustrate a series of chair positions from fully upright (Figure 2) to fully reclined (Figure The reclining chair 10 comprises a chair frame 11, the seat 12, a foot support 13 and a reclining mechanism 14 that supports the seat 12 and foot rest 13 and allows these components to be movable relative to the chair frame 11.

The reclining mechanism 14 includes a tilt actuator to assist an operator of the reclining chair to overcome the initial force required in tilting the seat into a reclined position against the weight of the occupier of the chair. The tilt actuator 20 as illustrated in the drawings is primarily operated by a person standing behind the reclining chair in order to recline a high dependency person seated in the chair.

The seat 12 comprises a seat base 15 and back support 16. The seat base 15 is supported on right and left sides by reclining linkage assemblies 30 that are mirror images of each other. Linkage assemblies 30 are fixed against movement relative to the chair frame 11 by pinning the assemblies each to side plates 31 that are fixed to the chair frame 11 along with cross members 32 spanning across the underside of the seat base and securely attached to the chair frame 11.

As best seen in Figure 4, each linkage assembly 30 is securely pinned to its respective side plate 31 at pins 39, 40 and 41. First pin 40 pins a direct link 42 at one end while the other end of direct link 42 directly attaches to the side of the seat base 15 close to the juncture between the seat base 15 and back support 16.

The pivotal connection of direct link 42 to the seat base is at pin 43.

\\melb_files\home\shirleyp\specis\P54088 Artistic Healthcare.doc 18/08/04 7 The second pin 41 on plate 31 pivotally connects a foot support link 44, which is in turn connected to a foot support linkage assembly The third pin 39 on plate 31 connects a tension link 47 between side plate 31 and a link member of the foot support linkage assembly Foot support linkage assembly 45 is designed to hold the foot support 13 in a folded condition when the chair is upright as illustrated in Figure 2. As the seat is inclined the linkage members of the foot support linkage assembly 45 move relative to the seat 12 and chair frame 11 to fold the foot support 13 out to an extended position where the foot support can support the feet and legs of an occupier of the chair.

The foot support linkage assembly comprises four link members 45a, 45b, 45c and 45d. Link members 45a and are pivotally connected end to end whereas linkage members and 45d are pivotally connected end to end. Link member 45a is pivotally connected at its centre with member 45d such that connected link members 45a and and connected members 45c and 45d form a scissor linkage.

This is best illustrated in Figure 4. The free ends of link members 45a and 45c are pivotally attached at a spaced distance to the same side of the seat base 15 and towards the front of the seat base. The free ends of link member 45b and 45d are pivotally attached to one side of the foot support 13. Link member 45b is attached closer to the center of the width of the foot support 13 while link 45d is attached closer to the rear corner edge of foot support 13. This is best illustrated in Figures 3 and 4.

\\melb_files\home\shirleyp\specis\P54088 Artistic Healthcare.doc 18/08/04 8 This scissor linkage assembly allows the foot support 13 and associated linkage assembly 45 to be folded into a relatively small space.

The foot support link 44 that is attached to side plate 31 is pinned to link member 45c in a slot 49 such that the foot support link 44 may rotate and slide relative to link member 45c as the foot support is being extended.

Both link members 45a and 45c are bent so as to correctly align and position the foot rest when extended and to provide stable support for an occupier's feet.

Tension link 47 specifically connects to link member at its bend.

Foot support link 44 and tension link 47 are provided to ensure the foot support linkage assembly is maintained stable and correctly aligned with respect to the person reclined in the chair.

The problem confronted by users is that the above described seat linkage assembly is stable when in the upright position as illustrated in Figure 2 and some force is required to overcome this stability in order to achieve chair tilt. The tilting reclining action of the seat relative to the chair is governed by direct link 42. With the occupier seated in the upright position the weight of the person tends to rotate direct link 42 as illustrated in Figure 2 in a counter-clockwise direction, thus keeping the person firmly in an upright position. To achieve movement to the second semi-reclined position as illustrated in Figure 3 direct link 42 is required to rotate in a clockwise direction to the position illustrated in Figure 3. Normally a seated person would lift themselves and take a significant proportion of their \\melb_files\homeS\shirleyp\apecis\P54088 Artistic Healthcare.doc 18/08/04 9 weight off the seat base and simultaneously apply a rearward force onto the back support 16 in order to cause direct link 42 to rotate in a clockwise direction past the top central point where the link is substantially vertical. From this point the mass under gravity of the seat and person on it can take effect to rotate direct link 42 further.

However elderly and sick people occupying the chair often do not have the strength to lift themselves and apply a rearward force on the seat to initiate clockwise rotation of link 42. Accordingly, the tilt actuator is required to overcome this initial force, and specifically to enable another person to safely apply the initial force.

The tilt actuator 20 includes an elongate member comprising a push tube 21 that is hollow and coaxially houses a lost motion telescopic rod 22 which moves reciprocally within the push tube. The elongate member comprising the push tube and telescopic rod is actuated by a pushing force pushing it in a direction substantially longitudinal to the length of the push tube. This force is transferred to the front underside of the seat base as an upward force that lifts the seat base against the weight of the occupier and moves it rearwardly to overcome the initial rotation of direct link 42. The tilt actuator keeps applying force until direct link 42 reaches a substantially vertical position where it can continue to rotate clockwise into a reclined position under the gravitational mass of the occupier and/or external downward force applied, for instance by a carer.

Reclining further to the fully reclined position illustrated in Figure 4 the seated user or another person applies a force to the back support 16 which tilts the front of the seat base 15 further upwards.

\\melb_files\home$\shirleyp\epecis\P54088 Artistic Healthcare.doc 18/08/04 10 To effect an upward force that will sufficiently overcome the initial rotation of direct link 42, the free outside end of the telescopic rod 22 is pivotally connected to a swinging cross bar 23. The swinging cross bar 23 is elongate in cross section such that the telescopic rod connected to the cross bar 23 at a lower end will impart a swinging motion on the cross bar and transfer a force to the upper end of the cross bar. The upper end of the cross bar is in turn pivotally connected to foot assembly link member 45a. A substantially longitudinal pushing motion on the push tube 21, and almost internal telescopic rod 22, will create an upward force on swinging cross bar 23 which will in turn apply a combined upward and rearward force on link member which will hence raise seat base 15 upwardly and rearwardly to overcome the initial closewise rotation of direct link 42.

The push tube 21 is long and extends to the rear of the chair. It is slightly bent at its rear half to assist the tilt actuator in achieving the required upward force to lift the seat base 15 past the initial reclining motion. The rear end of the push tube 21 is pivotally connected to a foot pedal 24, which is in turn pivotally secured to the chair frame 11 at an approximate center Figures 6(a) and 6(b) illustrate side and end views respectively of the push tube 21. Figure 6(c) illustrates a side view of the telescope rod 22. Figures 6(d) and 6(e) are side and end views respectively of swinging cross bar 23. And Figure 6(f) is a side view of pedal 24.

Referring to Figure 2, when foot pedal 24 is pushed down with a foot it rotates in a clockwise direction as illustrated in the drawing. Foot pedal 24 is pivotally connected to push tube 21 at pivot 26. Therefore, against frame 11 at point 25 rotation of the pedal 24 causes a \\.elbfies\home$\shireyp\pecia5\P40 Artistic Healthcare.doc 18/08/04 11 lever effect against push tube 21 and causes the rear end of push tube 21 to move upward along a slightly arcuate path to the position illustrated in Figure 3. This causes the front end of the push tube 21 to follow a similar path against swinging cross bar 23 which in turn, via link member 45a, lifts the front of seat base 15 up and around in a motion that is sufficient for the direct link 42 to clear its top center position.

Figure 3 illustrates the direct link 42 in a position where it has rotated in a clockwise direction and cleared its vertical top center position. Push tube 21 is extended to its maximum extension and pedal 24 is fully pressed.

From here only the weight of the occupier in the chair and/or a force applied to the back support 16 will cause the chair to tilt into a fully reclined position as illustrated in Figure 4. At this stage as illustrated in Figure 3 an operator is no longer required to push on peddle 24 and hence the pedal is biased to return to its original position as illustrated in Figure 4. The foot pedal 24 returns to its original upright position by way of a compression spring (not shown) As the foot peddle returns to its original upright position it pivots to pull push tube 21 down with it.

Because the front of the tilt actuator 20 is connected to the front of the reclining mechanism 14, which in Figure 4 is in a fully lifted position, the telescopically sliding rod 22 contained in the push tube 21 slides out of the push tube to make up for the lost motion caused by the extra distance the tilt actuator 20 needs to cover between the front of the seat base 15 and upright pedal 24. The telescopic rod 22 is, however, biased to return back into the push tube 21 when the seat is made upright by a return \\melb_files\hoe$\shirleyp\speci\s\P54088 Artistic Healthcare.doc 18/08/04 12 spring 34 connected between an inside far end of the telescopic rod 22 and an interior wall of push tube 21.

The spring 34 in the push tube 21 is designed to retract the telescopic rod 22 as the reclining chair 10 is moved back in to the upright seated position illustrated in Figure 2.

The angle of inclination of the seat 12 relative to the chair frame 11 can be set by using a hand brake illustrated in the figures including Figure 5. A hollow support post 51 extends downwardly from a cross member at the top of the seat back to a second cross member 56 mounted at the base of the chair frame 11. Support post 51 has an internal shaft 52 that slides in and out of the post 51 to shorten and lengthen the effective length of the post respectively.

The hand brake 50 is operated by a Bowden cable 53 having a steel pin at the opposite end of the cable to the handbrake. The spring is biased into aligned apertures in the support post 51 at the rear of the chair and the hollow shaft 52 slidable within the support post 51. The pin of the Bowden cable 53 extends through one aperture 57 in the support post 51 and then through any one of internal apertures on the hollow shaft 52 so as to fix the effective length of the support post 51 at a desired length. The post 51 is pinned at upper and lower ends to compensate for the tilting seat.

The reclining chair 10 may be provided with castor wheels at its base to allow the chair and an occupier of the chair to be wheeled around.

By incorporating the tilt actuator 20 in the present reclining chair 10 the seat may be tilted and reclined to a lower point than previously achieved with reclining \\melb-files\homeS\hirleyp\specis\PS4088 Artistic Healthcare.doc 18/08/04 13 chairs. Additionally, the tilt actuator allows for use of a more sophisticated foot support linkage assembly that is compact when folded and extends outwardly to a comfortable position. Previously, foot supports have been known to be simply pivotally connected to the chair frame at an upper end when in a closed folded and vertical position such that in use the foot support merely rotates through approximately 900 at the pivot point to be horizontal.

Accordingly, when folded, the depth of the foot support directly influences the height of the chair and hence the distance between an occupier's knees and feet when in an upright position. It was found that this distance was often too high leaving occupier's feet dangling above the ground.

This problem is overcome with the present reclining chair because the reclining mechanism 14 and foot support linkage assembly 45 are sufficiently compact to enable the seat to be lowered closer to the ground without the mechanisms interfering with the ground when extending and tilting.

The present reclining chair has been developed in consideration of the main factors involved in seating of aged persons. Specifically, the main factors are to maintain comfort, independence and dignity of elderly persons without compromising the safety of the carers. It is commonly agreed that as independent mobility is lost, an aged person begins a steady decline towards high care needs. The present reclining chair is considered to retard this decline rate by allowing a seated elderly person to maintain contact with the floor. It is thought that this provides them with a sense of independence and decreases their decline.

Since modifications within the spirit and scope of the invention may readily be effected by persons \\melb_files\home$\ahirleyp\specis\P54088 Artistic Healthcare.doc 18/08/04 14 skilled within the art, it is to be understood that this invention is not limited to the particular embodiment described by way of example hereinabove.

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Claims (18)

1. A reclining chair with a tilting actuator for initiating tilting movement, the reclining chair comprising a chair frame, a seat having a base and a back, the seat being movable relative to the chair frame between an upright position and a reclined position, and an actuator having an elongate member pivotally linked to the seat base such that actuation of the elongate member produces an upward force against the seat base to lift the seat base to a point where a downward force on the seat can complete the tilting movement to bring the seat into a reclined position.

2. The reclining chair claimed in claim 1 wherein the actuator further includes a swinging crossbar and linkage member wherein the elongate member is pivotally connected to the swinging crossbar, the swinging crossbar is pivotally connected to the linkage member and the linkage member is pivotally connected to the seat base.

3. The reclining chair claimed in claim 1 or claim 2 wherein the elongate member comprises a hollow push tube containing a lost motion telescopic rod which slides reciprocally within the push tubes and whereby actuation of the elongate member is affected by pushing the push tube and rod combination in a substantially longitudinal direction.

4. The reclining chair claimed in claim 3 wherein the telescopic rod maintains connection with the push tube by way of a return spring mounted between the rod and the push tube.

5. The reclining chair claimed in claim 4 wherein the spring is mounted between a front end of the telescopic rod and an inner rearward wall of the push tube. \\melbfiles\home$\Bhirleyp\pecia\P54088 ArtiatiC Healthcare.doc 18/08/04 16

6. The reclining chair claimed in claim 4 or 5 wherein the telescopic rod is pinned to the swinging crossbar.

7. The reclining chair claimed in claim 2 wherein the swinging crossbar has an elongate cross section, the elongate member being pinned at one end of the elongate cross section and the linkage member is pinned at the opposite end of the elongate cross section.

8. The reclining chair claimed in claim 7 wherein the swinging cross bar comprises two hollow bars joined adjacently along their lengths.

9. The reclining chair claimed in any one of the preceding claims wherein the elongate member is linked to the seat base at a forward end of the seat base and extends to the rear of the chair from where the elongate member is actuated.

10. The reclining chair claimed in claim 9 wherein the elongate member is actuated by a pedal pivotally connected to a rear end of the elongate member.

11. The reclining chair claimed in claim 3 wherein the push tube includes a bend to assist in a direct transfer of force from a rear of the elongate member to the swinging cross bar.

12. The reclining chair claimed in any one of the preceding claims wherein the chair includes a brake for controlling the degree of inclination of the seat.

13. A method of reclining a reclining chair having a seat movably supported on a chair frame, the method including: actuating from a rear of the chair an elongate member by applying a force on the elongate member substantially longitudinally of the elongate member, whereby movement of \\melbfiles\home$\shirleyp\specis\PS4088 Artistic Healthcare.doc 18/08/04 17 the elongate member produces an upward force on the seat to lift the seat to a point where a downward force on the seat can complete the tilting movement to bring the seat into a recline position.

14. The method claimed in claim 13 including a swinging crossbar pivotally connected to the elongate member by way of a force on the elongate member that in turn lifts a front section of the seat base.

The method claimed in claim 14 including lifting the seat base by way of a linkage member pivotally connected to the swinging crossbar by way of the force applied to the swinging crossbar by the elongate member, the linkage member being pivotally connected to the seat base.

16. The method claimed in any one of claims 14 or including extending the elongate member in length after the seat reaches the point where a downward force can complete the tilting movement.

17. The method claimed in any one of claims 14 to 16 including adjusting the degree of tilt by actuating a hand brake to release a locking mechanism thereby allowing the seat to freely tilt.

18. The method claimed in any one of claims 14 to 17 including applying a downward force on the seat by relying on the weight of the user seated in the seat and/or the downward force applied on the seat by another person. Dated this 18th day of August 2004 ARTISTIC HEALTHCARE SEATING PTY LTD By their Patent Attorneys GRIFFITH HACK Fellows Institute of Patent and Trade Mark Attorneys of Australia \\melb_files\home$\shirleyp\apecis\P54088 Artistic Healthcare.doc 18/08/04