Seat

Abstract: The invention relates to seat forms, the internal structure of a seat to which the seat owes its shape and to which padding is applied. The seat form (60) has a back portion (61) and a base portion (62). The lengths of the portions are extendable by addition of extension segments (91) and (92). The form may be formed in two halves (61) and (62) interconnected by a plurality of multileaved hinges (63) to allow the angle between the back portion and base portion to be varied. The extension segments (91) and (92) are secured to the previous extension segment or to the basic portion by two segment bolts (68) which have a threaded shaft (70) and a slotted head (69) with a threaded bore (71). The bolts engage a threaded bore (67) in the base or back portion or the threaded bore (71) of the previous segment bolt (68). A pommel (81) is releasably connected to the base portion (62) to improve abduction.

Description: This invention relates to seats and in particular to the internal structure of a seat to which padding is applied and from which the seat gets its shape, known as a seat form. In the past, seats have been made from seat forms of a standard size and therefore each seat developed with that particular form had one standard size. If a seat is required to be shortened or lengthened a separate seat form has to be developed and manufactured from which to make the seat. US 4585272 (Ballarini) discloses a chair having a reclinable back rest which is formed by a plurality of superimposed segments articulated together about respective substantially horizontal axes to define, in the reclined position of the back rest, an arcuate configuration with a curve substantially corresponding to the arched back of a user. A resistance means is provided to resist the movement of the segments towards the position corresponding to the reclined position of the back rest. In a preferred embodiment, there are five segments connected to a seat and forming a back rest. However, in the disclosed arrangement it is not possible to adjust the number of segments in the back rest in order to adjust its length. The present invention provides a seat form which comprises a back portion and a base portion secured to the back portion and is characterised in that the seat form includes one or more extension segments arranged to be secured to the base portion or to a said extension segment previously secured to the base portion, and one or more extension segments arranged to be secured to the back portion or to a said extension segment previously secured to the back portion, in such a manner that each segment abuts the back or base portion or one of the adjacent previously secured extension segments, thereby enabling the length of the back portion and the base portion to be extended. The seat form in accordance with the present invention may be extended in the back portion and the base portion, so that seats of different sizes may preferably be made using a standard form with standard extension segments. Preferably, this type of seat has particular application in hospitals where seats of varying sizes may be required, e.g., on pushchairs for severely physically handicapped people or for wheelchairs so that the persons of different physical sizes may be readily accommodated. The use of such a seat form may have applications in a vast array of situations, including such circumstances as car seats for children and in other areas in which seat forms of varying sizes may be required, the form may be created so that the seat portion and back portion of the seat form are integrally formed so that the relative angle between the seat portion and back portion is fixed at a predetermined angle or the seat form may be constructed so that the relative angle may be adjusted to suit the user's requirements. Preferably, the seat form has raised sides extending along the base portion and base extension segments. Preferably, the base portion of the seat form has a forward facing surface and base extension segments have parallel front and rear surfaces similar to the forward facing surface wherein a first base extension segment is secured to the base portion such that the forward facing surface abuts the rear surface of the first base extension segment and additional base extension segments abut the preceding segment, rear surface to front surface whereby the length of the base portion is extended without changing the profile of the front surface of the base portion of the seat form. Preferably, the back portion of the seat form has an upward facing surface and the base extension segments have parallel upper and lower surfaces similar to the upward facing surface, wherein a first back extension segment is secured to the back portion such that the upward facing surface abuts the lowest surface of the first back extension segment and additional back extension segments abut the preceding segment, lower surface to upper surface, whereby the length of the back portion of the seat form is extended without changing the profile of the upper surface of the seat form. Preferably, the back portion and the base portion are secured in a manner allowing the relative angle formed between the back and base portions to be varied. Preferably, a pommel is removably secured to the base portion. Preferably, the location of the pommel on the base portion is variable. Preferably, the pommel is formed in segments and is adjustable in length to suit the base portion by removing or adding segments as required. Preferably, the seat is adapted for use with a push chair or the like and has a base plate moulded or otherwise secured to the base portion to facilitate mounting of the seat to the frame of the push chair, etc. Preferred embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:- Figure 1 illustrates one embodiment of a seat form in accordance with the present invention; Figure 2 is a side elevational view of another embodiment of a seat form in accordance with the present invention showing how the back and base portions are connected; Figure 3 is an end elevational view of the seat form of Figure 2; Figure 4 is a view from above of the seat form of Figure 2 with the back and base portions separated for clarity; Figure 5 depicts a segment bolt used to connect segments to the back and base portions of the seat form; Figure 6 is a side elevational view of a pommel in accordance with the present invention; Figure 7 is a view from above of the pommel of Figure 6; Figure 8 is an end elevational view of the pommel of Figure 6; Figure 9 is an end elevational view of a section through the pommel of Figure 6; Figure 10 depicts a segment used to extend the length (height) of the back portion; Figure 11 depicts a segment used to extend the length of the base portion; Figure 12 depicts a back extension segment incorporating a recess for mounting a head rest and/or restraint means; Figure 13 depicts a restraint mount for use with the extension segment of Figure 12; Figure 14 depicts a head rest mount for use with the extension segment of Figure 12; and Figure 15 illustrates how the mounts are secured to an extension segment as shown in Figure 12. The seat form illustrated in Figure 1 has a back portion and a base portion which are formed integrally and thus have a fixed relative angle formed therebetween. The seat form 60 has a a back portion 61 and a base portion 62. Connected to the back portion is a series of back extension segments 91 extending the height of the back portion. Connected to the base portion 62 is a series of base extension segments 92 extending the length of the base portion of the seat form. The base portion is illustrated as having raised sides 94 to support the legs of the user. The raised sides are extended by the extension segments 92. A pommel 81 is formed in the base portion of the seat form and is also extended by the extendion segments. The pommel is provided for improving abduction of the user. In certain situations it is advantageous to provide a seat form in which the angle formed between the back portion and the seat portion may be varied. Such a seat form forms the basis for the preferred embodiment of this invention and is illustrated in Figures 2, 3 and 4. As illustrated in these Figures, the seat form 60 of the preferred embodiment has two basic portions, a back portion 61 and a base portion 62. Four friction hinges 63 are used to secure the two portions together. Each frictional hinge comprises four tongues 64 extending from the back portion and interleaved with three tongues 65 extending from the base portion, the tongues being clamped together by a bolt 66. The relative angle between the two portions may be readily adjusted when the bolts 66 are slackened and once the desired angle has been formed for maximum personal comfort and support for the individual user, the bolts 66 are tightened to rigidly secure the two portions at the desired relative angle. Thus it can be seen that although the portions are rigidly held in a fixed relative orientation with each other, the angle can be adjusted to suit individual requirements. It is not envisaged that the seat would be used in a situation where the angle would be adjusted frequently, rather only occassionally, e.g. when the seat is used in conjunction with a wheelchair or the like and the wheelchair is to be used by another person. It is envisaged that the angle of the seat would be adjusted when the seat is being tailored to suit its owner/user, i.e. when the length of the back and/or base portions are being changed or selected. Of course, other infrequent adjustments may be made and the ability to make such adjustments is accommodated. Both the back portion and the base portion are provided with threaded sockets 67 moulded into or otherwise attached to the portions for securing extension segments 91, 92 as shown in Figures 10 and 11 to the portions by means of segment bolts 68. The segment bolt as shown in Figure 5 has a head 69 and a threaded shaft 70. The top of the head is slotted to receive a screw-driver and the head has a threaded bore extending axially therein to receive the threaded portion of another segment bolt. In this manner, while the first extension segment is secured to the portion, additional segments are secured to the preceding segment by segment bolts screwed into the segment bolts of the preceding segment. Each extension segment 91, 92 is provided with holes 93 therethrough to accommodate the segment bolts. Each hole 93 is provided with an enlarged opening portion to accommodate the head of the segment bolt so that the segment bolts do not protrude from the completed seat form. The base portion is provided with a C-shaped channel 80 extending axially along and flush with the seating surface of the base portion 62. The channel is open to the seating surface and extends from the outer edge of the base portion a short distance towards the back portion. This channel 80 is arranged to accommodate the head of a Tee-bolt used to secure a pommel 81. The pommel of the preferred embodiment is segmented with a curved leading segment 82 and a number of additional segments 83. The segments are connected by joining webs 84. The required length of the pommel 81 is achieved by cutting the appropriate web 84. Each segment has a hole 85 passing therethrough to accommodate the shank of the Tee-bolt. The upper opening of the hole has an enlarged portion 86 to receive the nut which is threaded onto the Tee-bolt to fasten the pommel to the base portion. As the channel 80 is continuous the location of the pommel may be varied by sliding the head of the Tee-bolt along the channel until the pommel is in the desired location. A guide 87 may be provided to assist in locating the pommel in the opening of the channel 80. A mounting plate 90 may be provided as a convenient method of mounting the seat form to the required framework. The framework may, for example, be the frame of a wheelchair, push chair or the like, a swivel base and legs for a standard chair or a special arrangement for mounting the seat in a vehicle. The mounting plate may be moulded or otherwise secured to the base portion of the seat form. In the particular case when the user is physically impaired the mounting plate allows the seat to be easily exchanged or relocated from a push chair, for example, to a vehicle so that the user is at all times able to gain the benefit of using a customised seat catering for his particular requirements. The seat form may provide means for attaching a head rest and/or means for attaching a restraint means. The restraint means is normally in the form of a seat belt arrangement in which webbing is pasted over certain parts of the body to hold the user in the chair. In the embodiment shown in Figures 12 to 15, the extension segments used to extend the back portion of the seat form have a stepped recess 100 in the form of a recess within a recess as is more clearly illustrated in Figure 15. The mounts 101 and 102 for the restraint means and the head rest respectfully, have a similar step or enlarged portion 103 at one end shaped to be located within the recess 100. The restraint mount 101 shown in Figure 13, is formed from a sheet of metal with one end folded over to form the enlarged portion 103. The other end has a slot formed therein to accommodate webbing (not shown) used as the restraint in the usual manner. The head rest mount 102 shown in Figure 14, comprises a plate 104 to which is welded two triangular plates 105, each with a hole therethrough and each extending perpendicular to the plate at respective ends thereof, as illustrated. The plates 105 are arranged to be bolted to a head rest (not shown) which extends above the back portion of the seat form to support the head of the user. Attached (welded) to the rear of the plate 104 is a tongue 106 which is similar to the restraint mount 101 but without the slot. The stepped portion 103 of the tongue 106 is arranged to be fitted into the recess 100 and extend away from the seat form so that the plate 104 extends along the outer surface of the back portion so that the plate is secured against the back of the back portion of the seat form by the tongue 106 being held captive in the recess 100. Figure 15 illustrates how the tongue 106 is secured within the recess 100, with the back portion extension segments 91 being shown in sectional view. The restraint mount is similarly held captive. The mounts are placed so that the enlarged portions 103 nest within the deeper portion of the recess 100 and the extension segment 91 is secured to the back portion or an adjacent extension segment by segment bolts as depicted in Figure 23. The position of the mounts may be adjusted by sliding the mounts along the recess 100. Normally two restraint mounts and one head rest mount would be located within the recess of the last extension segment fitted, however, any combination may be used and the recess of any segment may be used. Once the required location along the recess has been achieved the amounts are firmly held in that position by tightening the segment bolts, thus causing the mounts to be clamped in position between the extension segments.

Claims: A seat form, comprising a back portion (61), and a base portion (62) secured to the back portion, characterised in that the seat form includes one or more extension segments (92) arranged to be secured to the base portion or to a said extension segment previously secured to the base portion, and one or more extension segments (91) arranged to be secured to the back portion or to a said extension segment previously secured to the back portion, in such a manner that each segment abuts the back or base portion or one of the adjacent previously secured extension segments, thereby enabling the length of the back portion and the base portion to be extended. A seat form as claimed in claim 1 characterised in that connecting means are provided enabling each extension segment to be individually securable to the back or base portion or to a previously secured extension segment. A seat form as claimed in claim 2, characterised in that the connecting means includes segment bolts (68) and wherein each extension segment has holes (93) therethrough for receiving the segment bolts, the back and base portion having threaded sockets (67) therein such that a first extension segment can be secured to the base and/or the back portion by extending segment bolts (68) through the holes (93) of the first extension segment and into the threaded socket (67) of the base and/or back portion. A seat form as claimed in claim 3, characterised in that the segment bolts each have a head (69) on an upper end and a threaded shaft (70) on a lower end, said head having a bore (71) extending axially therein to receive the threaded shaft of another segment bolt, such that additional extension segments can be secured to preceding extension segments by threading the segment bolts (68) of the additional extension segments into the bore of segment bolts of the preceding extension segment. A seat form as claimed in any one of the preceding claims, characterised in that the seat form (60) has raised sides (94) extending along the base portion (62) and the base extension segments (92). A seat form as claimed in any one of the preceding claims, characterised in that the base portion (62) has a forward facing surface and the or each base extension segment (92) has parallel front and rear surfaces similar to the forward facing surface wherein a first base extension segment is secured to the base portion (62) such that the forward facing surface abuts the rear surface of the first base extension segment and additional base extension segments abut the preceding segment, rear surface to the front surface, whereby the length of the base portion (62) is extended without changing the profile of the front surface of the base portion of the seat form (60). A seat form as claimed in any one of the preceding claims, characterised in that the back portion (61) of the seat form has an upward facing surface and the ore each back extension segment (91) has parallel upper and lower surfaces similar to the upward facing surface, wherein a first back extension segment is secured to the back portion such that the upward facing surface abuts the lower surface of the first back extension segment and additional back extension segments abut the preceding segment, lower surface to upper surface, whereby the length of the back portion of the seat form is extended without changing the profile of the upper surface of the seat form (60). A seat form as claimed in any one of the preceding claims, characterised in that the back portion (61) and base portion (62) are formed as two separate portions secured together in a manner allowing the relative angle formed between the back and base (61, 62) portions to be varied. A seat form as claimed in claim 8, characterised in that the back and base portions are connected by way of a hinge (63). A seat form as claimed in claim 9, characterised in that the hinge (63) is a multileaved friction hinge. A seat form as claimed in claim 10, characterised in that there are a plurality of hinges (63) interconnecting the back and base portions (61, 62). A seat form as claimed in any one of the preceding claims, characterised in that a pommel (81) is provided no the base portion. A seat form as claimed in claim 12, characterised in that the location of the pommel (81) on the base portion (62) is adjustable. A seat form as claimed in claim 12 or claim 13, characterised in that the pommel (81) is formed in segments (82, 83) and is adjustable in length to suit the base portion (62). A seat form as claimed in any one of the preceding claims, characterised in that the seat form (60) has a base plate moulded or otherwise secured into the base portion (62) to facilitate mounting of the seat form to a framework. A seat form as claimed in claim 15, characterised in that the base plate is adapted to enable the seat to be interchanged between the framework of a pushchair or the like and a vehicle.

Inventors: LAND ANN LOUISE, OGLE CHRISTOPHER LEON, LAND, ANN LOUISE, OGLE, CHRISTOPHER LEON
Applicants: LAND ANN LOUISE, NORTHERN TERRITORY AUSTRALIA, OGLE CHRISTOPHER LEON, LAND, ANN LOUISE, OGLE, CHRISTOPHER LEON, THE NORTHERN TERRITORY OF AUSTRALIA
Application year: 1988
Main classification: A61G5
IPC codes: A47C31, G11C11, A61G5, B62B9, G11C5, A47C7, A47C4