REST ASSEMBLY

Technology field The present invention relates to chairs. More specifically, the present invention relates to chairs with leg rests. Particularly, the present invention relates to a leg rest assembly and a method for operating said leg rest assembly.

Background Chairs having different types of leg rests are known in the art. Leg rests are arranged on chairs so as to ease pressure on a chair user’s legs and thus relieve back stress. Leg rests also encourage good posture by helping the user to sit all the way back and in an upright position. Moreover, leg rests provide ergonomic comfort for the chair users. In certain environments, such as in environments related to patient treatment, healthcare, hospitals or other caretaking locations, leg rests are typically operated by caretaking or nursing staff whilst e.g. patients or hospitalized persons are presently sitting in the associated chair. Leg rests in mechanical patient chairs typically consist of integrated foot and calf rests, an unwieldy separate component which is mountable on and dismountable from the patient chair by hinge mechanisms. In many cases the construction is such that when transporting the patient chair, for instance in a narrow lift, lavatory /bathroom, the leg rest (sometimes separate for left leg and right leg, sometimes one component for both feet) must be dismounted. Particularly in mechanical patient chairs, they have only one use position, corresponding to a normal sitting position of an "average" patient, supporting one or both legs of the patient. They are often in the patient's way when he/she is to be seated in the patient chair or be moved from the patient chair by carers. They can also be in the way of patients who can walk fairly well and can sit down on their own in a normal chair, but must first be seated before the position of the legs is arranged. Any possibility of dismounting is merely occasionally used by carers, since dismounting and subsequent mounting is considered difficult and time consuming. When moving a patient from the patient chair, for instance from a wheelchair to a shower chair or from a shower chair to a bed, the patient's legs must be lifted separately by the caretaker if the patient himself is incapable of raising his legs, thus facilitating the movement of the patient. Lifting of legs is heavy work for the carers, especially in view of the fact that the carers must perform this operation in an ergonomically unsatisfactory position. The leg rests of some patient chairs fitted with electronics are electronically pivotable outwards and inwards, allowing the legs to be straightened out from the normal sitting position. Such a construction controlled by electronics, of course, makes the manufacture of the patient chair expensive and does not allow easy dismounting and/or moving away of the leg support. This would be necessary, for instance, before entering a narrow lift, or when the patient is seated on a shower/toilet chair over a toilet/bedpan in which case a more upright sitting position is desirable.

Prior art solutions typically involve mechanical arrangements of many moving parts, such as spring-loaded mechanisms or ratchet wheels. Others leg rest solutions are in a complicated way fitted with electronics for raising and lowering the seat, inclination backwards, inclination of leg rest, and so forth. Some solutions have the convenience of the caretaking or nursing staff in view, while others are more concentrated on the patient's convenience. Sometimes these kinds of convenience seem to be incompatible, especially in mechanical patient chairs. Many patients are incapable of communicating their needs or wishes or discomfort to their caretakers.

Hence, in light of the observations above, it is of particular importance that leg rests can satisfy a variety of quality and functionality attributes. Such attributes involve, for instance, ease of operation for both a currently used and an idle chair for either one of an operator or a person being seated in the chair, resting angle adjustments, accident prevention or at least alleviation with regards to the risk of pinches on moving parts, an easy and quick attachment and detachment of the leg rest, and/or facilitation of cleaning. A cost-efficient solution that can satisfy the above presented attributes is also wanted.

Summary It is accordingly an object of the invention to solve, eliminate, alleviate, mitigate or reduce at least some of the problems and shortcomings referred to above.

In this disclosure, a solution to the problem outlined above is proposed. In the proposed solution, a leg rest assembly is described.

In a first aspect of the invention, a leg rest assembly for a chair is provided. The leg rest assembly comprises a seat portion; a leg rest portion adapted to be movable between a lower end position and an upper resting position; a hinge mechanism arranged at the seat portion, wherein the hinge mechanism comprises one or more hinge tracks, at least one thereof having a cam-shaped profile with one or more recesses being associated with the upper resting position; and a pivoting portion comprising a first lateral end adapted to be arranged at the hinge mechanism, and a second lateral end being connected to the leg rest portion.

According to one embodiment, the leg rest portion is adapted to be movable between one or more intermediate positions from the lower end position to the upper resting position, wherein the one or more hinge tracks comprises more than one recess, the additional recesses being associated with the one or more intermediate positions.

According to one embodiment, the pivoting portion comprises a first pivoting arm and a second pivoting arm each one of the pivoting arms having first and second lateral ends.

According to one embodiment, at least one of the first lateral ends of the pivoting arms comprises a projecting guide knob adapted to be guided along a first side and a second side of a respective hinge track by a corresponding partly circular sweeping motion of the pivoting arms.

According to one embodiment, the one or more recesses are located along the first side of said hinge track having a cam-shaped profile, and wherein the second side has a substantially planar surface.

According to one embodiment, the leg rest portion is maintained in the upper resting position or in the one or more intermediate positions upon the projecting guide knob(s) being guided to the associated recess and while a load is affecting the leg rest portion. According to one embodiment, the leg rest portion is further movable to an upper end position being located vertically above the upper resting position, wherein upon the leg rest portion being positioned in the upper end position, the projecting guide knob(s) being guided past the recess associated with the upper resting position.

According to one embodiment, upon the leg rest portion being positioned in the upper end position, movement thereof is freely allowed to the lower end position by the one or more projecting guide knob(s) being correspondingly guided along the second side of said hinge track having a cam-shaped profile.

According to one embodiment, upon the leg rest portion being positioned in the upper end position, the pivoting portion is detachable from the seat portion.

According to one embodiment, the pivoting portion has a generally tubular shape.

According to one embodiment, the leg rest portion is positioned at an angle with respect to the seat portion, wherein in the lower end position, the angle is approximately 5° perpendicular to the seat portion, and in the upper resting position, the angle is approximately 15° in parallel with the seat portion.

According to one embodiment, the hinge mechanism is arranged on the underside and close to a front edge of the seat portion.

According to one embodiment, details of the hinge mechanism are cast.

According to one embodiment, the chair is a patient chair adapted to be operated by a caretaker.

In a second aspect of the invention, a chair comprising a leg rest assembly according to the first aspect or any embodiment dependent thereon is provided.

It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps, or components, but does not preclude the presence or addition of one or more other features, integers, steps, components, or groups thereof. All terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to "a/an/the [element, device, component, means, step, etc]" are to be interpreted openly as referring to at least one instance of the element, device, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.

A reference to an entity being “designed for” doing something in this document is intended to mean the same as the entity being “configured for”, or “intentionally adapted for” doing this very something.

Brief description of the drawings

The foregoing will be apparent from the following more particular description of the example embodiments, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the example embodiments.

Figures la-c are schematic side views of a chair having a leg rest assembly according to one embodiment.

Figure 2a is a schematic underside view of a pivoting portion attached to a leg rest portion according to one embodiment.

Figure 2b is a schematic front view of the embodiment according to Figure 2a.

Figure 3a is a schematic front view of an embodiment of a projecting guide knob.

Figure 3b is a schematic side view of the embodiment according to Figure 3a.

Figure 4 is a schematic cross-sectional view of a pivoting portion being connected to a seat portion according to one embodiment.

Figure 5a is a schematic underside side view of an embodiment of a hinge mechanism.

Figure 5b is a schematic front view of the embodiment according to Figure 5a.

Figure 5c is a schematic side view of the embodiment according to Figures 5a and 5b.

Figure 6a is a schematic underside view of a hinge mechanism according to one embodiment.

Figure 6b is a detailed view of a part of the hinge mechanism according to the embodiment of Figure 6a. Figure 7a is a schematic upper front view of a chair according to one embodiment.

Figure 7b is a detailed view of a part of the chair according to the embodiment of Figure 7a.

Detailed description of the embodiments

Embodiments of the invention will now be described with reference to the accompanying drawings. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The terminology used in the detailed description of the particular embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. In the drawings, like numbers refer to like elements.

With reference to Figures la-b, a schematic side view of a chair 100 comprising a leg rest assembly 10 is shown. In preferred embodiments of the present disclosure, the chair 100 is a patient chair 100, i.e. a chair 100 wherein patients are seated or adapted to be seated. The patient chair 100 may be used in environments related to patient treatment, healthcare, hospitals or other caretaking locations. The patient chair 100, and particularly the leg rest assembly 10, may be operated by caretaking or nursing staff whilst e.g. patients or hospitalized persons are presently sitting thereon. The leg rest assembly 10 may alternatively be operated by patients currently being seated in the chair 100. Yet alternatively, the leg rest assembly 10 may be operated in an idle mode, i.e. currently not having a person being seated in the chair 100. Alternatively, or additionally, the chair 100 having the leg rest assembly 10 may be adapted to be used in other environments. Such other environments may practically be any type of environment wherein chairs 100 having a leg rest 10 can appropriately be used, including but not limited to home environments, office environments, recreational environments, hotels, lounges, stores, malls, beaches, hairdressing or beauty salons, and so forth. The skilled person may realize other appropriate environments wherein a chair 100 having a leg rest assembly 10 can be used. The leg rest assembly 10 shown in Figures la-b comprises several different portions being at least to some extent mechanically or structurally coupled with one another. As the illustrated chair 100 merely serves as an example of a chair 100 according to one particular embodiment, the chair 100 is not restricted to having the different portions which now will be described. The chair 100 may in alternative embodiments comprise fewer or lesser portions or components, given that the inventive aspects of the present disclosure can be achieved. This particular embodiment comprises a seat portion 20, a leg rest portion 30, a hinge mechanism 40, a pivoting portion 50 and armrest portions 60.

The seat portion 20 may be adapted to receive and seat a body part of a human user, typically a body part extending from approximately the knees to the lower back end. The chair 100 and/or the seat portion 20 may be further arranged with the armrest portions 60 for allowing a user to rest his or her arms while being seated.

The pivoting portion 50 comprises a first lateral end 52 being arranged at the hinge mechanism 40 that is arranged at the seat portion 20. Moreover, the pivoting portion 50 comprises a second lateral end 56 being connected to the leg rest portion 30. The connection between the second lateral end 56 and the leg rest portion 30 may involve using any type of attachment means known in the art, such as e.g. couplings using screws, bolts, knobs, welds, brazes, adhesive materials, and so forth. The pivoting portion 50 is preferably made of a material that can provide a spring-load when put under tension, such as e.g. steel alloys including but not limited to high-carbon, oil- tempered low-carbon, chrome silicon, chrome vanadium or stainless steel.

Alternatively, the material of the pivoting portion 50 may be either one of beryllium copper, phosphor bronze, titanium, rubber or urethane. Any of the above listed materials may yet alternatively be used in combination with one another. The pivoting portion 50 may have a generally tubular shape, or any alternatively appropriate shape, being capable of withstanding high loads caused by a part of the user’s lower body and generate a lateral spring effect.

The leg rest portion 30 may be adapted to receive a body part of a human user, typically a body part extending from approximately the knees to the ankles or feet. For the sake of simplicity, the body part being received by the leg rest portion 30 will hereinafter be referred to as “legs”. The leg rest portion 30 and/or the seat portion 20 may be arranged with extra padding to provide the seated user with extra comfort and ergonomic support. The respective lengths of the leg rest portion 30 and the seat portion 20 may vary. In one embodiment, the respective lengths of the leg rest portion 30 and the seat portion 20 may be dynamically adjusted depending on body dimensions of the current user. In one embodiment, the leg rest portion 30 is constructed as a single member being adapted to receive both of the user’s legs at similar angular positions. In another embodiment, the leg rest portion 30 may be a constructed as having two separate leg rest members, each leg rest member being adapted to receive a respective leg of the user. Hence, each one of the user’s legs being positioned on top of the leg rest portion 30 can in this embodiment be positioned at different angular positions.

In Figure la, the leg rest portion 30 is arranged in a lower end position 32, and in Figure lb, the leg rest portion 30 is arranged in an upper resting position 34.

The lower end position 32 can alternatively be interpreted as a folded-down position. Hence, in the lower end position 32, the user being seated in the chair 100 is not currently being supported by the leg rest portion 30. In one embodiment, the leg rest portion 30 is in its lower end position 32 positioned in an angle a being approximately 5° perpendicular to the seat portion 20. “Approximately” may in this sense correlate to a few degrees varying in either angular direction with respect to the seat portion 20. The angle a may vary depending on e.g. different characteristics of the chair 100, such as material choices or attachment and/or alignments means of different portions. Alternatively described, the angle a may vary anywhere between a perpendicular angle with respect to the seat portion 20, to an angle a wherein the user still has not started to receive support from the leg rest portion 30 or a position wherein the leg rest portion 30 is not yet erect.

The upper resting position 34 is to be interpreted as a maximum folded-up position wherein the user can actively be supported by the leg rest portion 30. In one embodiment, the leg rest portion 30 is, in the upper resting position 34, positioned at an angle a being approximately 15° in parallel with the seat portion 20. Similar to what was described with reference to the lower end position 32, “approximately” may in this sense correlate to a few degrees varying in either angular direction with respect to the seat portion 20. It is thus realized that the angle a may be substantially parallel with the seat portion 20.

The leg rest portion 30 is adapted to be movable between the lower end position 32 and the upper resting position 34. Furthermore, although not explicitly illustrated in Figures la-b, the leg rest portion 30 may be adapted to be movable between one or more intermediate positions 33, wherein the intermediate positions 33 are angularly positioned between the lower end position 32 and the upper resting positions 34. Hence, the angle a may assume different values between the value of the lower end position 32 and the upper resting position 34 during movement of the leg rest portion 30 therebetween.

Figures 2a-b are schematic views of an embodiment of a pivoting portion 50. In Figure 2a, the pivoting portion 50 and the leg rest portion 30 is seen from an underside view. Figure 2b shows a front view of the leg rest portion 30 and the pivoting portion 50.

In accordance with the illustrated embodiment, the pivoting portion 50 comprises a first pivoting arm 51 and a second pivoting arm 55, each one of the pivoting arms 51, 55 having first and second lateral ends 52a-b, 56a-b. In alternative embodiments, the pivoting portion 50 may have three or more pivoting arms 51, 55, each one of the three or more pivoting arms 51, 55 having first and second lateral ends 52a-n, 56a-n.

The pivoting arms 51, 55 may be arranged substantially parallel to one another. Alternatively, the pivoting arms 51, 55 may be arranged at separate angular positions in relation to one another. This may be realized differently depending on the construction of the leg rest portion 30 in accordance with how the user’s legs are being positioned, as was previously described with reference to Figures la-b.

Shown in Figures 2a-b are also two projecting guide knobs 53, 57, each one being arranged at respective lateral ends 52a-b of the pivoting arms 51, 55. In other embodiments wherein the pivoting portion 50 comprises a single pivoting arm 51, or three or more pivoting arms 51, 55, the pivoting portion 50 may be arranged with one projecting guide knob 53, 57 for each pivoting arm 51, 55 or at the single member. In the embodiment shown in Figures 2a-b, the projecting guide knobs 53, 57 are formed differently. Some of the inventive concepts of the present disclosure is based on how the projecting guide knob 53 on the first pivoting arm 51 is formed.

It is typically cheaper to manufacture the projecting guide knob 57 which is illustrated on the second pivoting arm 55. Hence, having two, or even more, projecting guide knobs 53, 57 being formed differently can provide savings during the manufacturing process, given that at least one is formed according to the projecting guide knob 53 as illustrated on the first pivoting arm 51. However, in some embodiments, both (or all) of the projecting guide knobs 53, 57 may be formed similarly. Nevertheless, hereinafter and throughout the detailed description, focus will be directed at the structure and shaping of the projecting guide knob 53 being located on the first lateral end 52 of the pivoting portion 50.

Figure 3a illustrates a front view of an embodiment of a projecting guide knob 53 being located on a first lateral end 52 of a pivoting portion 50. In Figure 3b, the same embodiment as shown in Figure 3a is seen from a side view.

In one embodiment, the details of the projecting guide knob 53 are cast. Alternatively, the details of the projecting guide knob 53 are shaped based on remainders of a milled out first lateral end 52. The skilled person realizes any alternative methods or processes of creating details similar such as the ones shown in Figures 3a-b. The details of the projecting guide knob 53 are preferably formed such that they fit a corresponding hinge track 42, which will be described in further detail later on in this disclosure with reference to Figures 6a-b.

Figure 4 shows a cross-sectional view of a pivoting portion 50 being connected to a leg rest portion 30 according to one embodiment. In this embodiment, it can be seen that the respective second lateral ends 56a-b of the two pivoting arms 51, 55 are bent towards one another and are adjoining at a connection portion 58 of the pivoting arms 51, 55. Hence, the respective lateral ends 56a-b of the two pivoting arms 51, 55 are, in this embodiment, together forming a U-shaped profile. As a result, the pivoting portion 50 is adapted to create lateral spring effect.

The respective lateral ends 56a-b may in alternative embodiments be connected differently via for instance the connecting portion 58, such that e.g. different shapes are formed. Preferably, such shapes also provide a lateral spring effect. In yet alternative embodiments, the pivoting portion 50 is arranged such that a minimum amount of materials is required to still be able to fulfill its inventive concepts, i.e. to generate a lateral spring effect and minimize manufacturing costs and/or complexity.

Figures 5a-c illustrate schematic views of an embodiment of a hinge mechanism 40 being arranged at a seat portion 20. In Figure 5a, the hinge mechanism 40 is seen from an underside side view. Figures 5b and 5c show a front view, and a side view, respectively, of the embodiment shown in Figure 5a.

In Figures 5a-c, the hinge mechanism 40 is arranged on the underside and close to a front edge of the seat portion 20. Hence, attaching and detaching the pivoting portion 50 with respect to the hinge mechanism 40 is made simple. In alternative embodiments, the hinge mechanism 40 may be arranged at any suitable location on or near the hinge mechanism 40. The hinge mechanism 40 may, for instance, be arranged on a support structure (not shown) that is being attached to at least one side of the seat portion 20.

The hinge mechanism 40 may comprise at least one receiving slot 47a-n. In the embodiment shown, the hinge mechanism 40 comprises two receiving slots 47a-b. Not shown, but still made apparent thanks to Figures 1-4 and the text associated therewith, is that each receiving slot 47a-b may comprise an insertion hole 48a-b adapted to enable the pivoting portion 50 to be fitted inside the associated receiving slot 47a-b. More specifically, the insertion holes 48a-b may be adapted to enable the first lateral ends 52a-b to be fitted inside the associated receiving slots 47a-b, such that the associated projecting guide knob 53, 57 can be guided therein. The pivoting portion 50 may be manually slidable into the receiving section(s) 47a-b via the associated insertion hole(s) 48a-b.

With reference to Figures 6a-b, a hinge mechanism 40 according to one embodiment is shown. Figure 6a shows the hinge mechanism 40 as a schematic underside view. Figure 6b shows a detailed view of a hinge track 42 of the hinge mechanism 40. The shown embodiment merely illustrates an example of how the hinge mechanism 40 may be formed, and are by no means to be interpreted as limiting examples. However, in preferred embodiments, the details of the hinge mechanism 40 are cast. Alternatively, portions of the hinge mechanism 40 may be milled out. As seen in Figure 6a, the hinge mechanism 40 comprises a single hinge track 42 being arranged at the left side thereof. In other embodiments, the hinge mechanism 40 may comprise two or more hinge tracks 42. The hinge track(s) 42 may be arranged at any appropriate location on a surface 41 of the hinge mechanism 40.

The hinge track 42 may be arranged or formed so as to enable a projecting guide knob 53 to be guided therealong. In one embodiment, the projecting guide knob 53 is adapted to be guided along the hinge tracks 42 by a corresponding partly circular sweeping motion of the pivoting portion 50 carrying the projecting guide knob 53, and more specifically the pivoting arms 51, 55. The partly circular sweeping motion may, for instance, be provided by a manual force being applied to the leg rest portion 30 by an operator thereof. At least one hinge track 42 is formed as having a cam-shaped profile. This can be seen in Figures 6a-b.

In different embodiments of the invention, any number of hinge tracks 42 may have a cam-shaped profile, and not just the one as shown in the figures. However, the inventive concepts of the present disclosure may in one embodiment be provided by just having one hinge track 42 being shaped in accordance with the cam-shaped profile.

Such hinge track 42 shape allows for the associated projecting guide knob 53 to be guided up and down along a first and a second side 45, 46 of said hinge track 42 in response to, for instance, said correspondingly partly circular sweeping movement of the pivoting portion 50.

The hinge track 42 having a cam-shaped profile may comprise one or more recesses 44. Each one of the one or more recesses 44 are associated with a corresponding resting position, i.e. a position wherein the user of the chair 100 can his or her legs. The resting position may, for instance, be the upper resting position 34 or any number of intermediate positions 33 between the lower end position 32 and the upper resting position 34. Hence, depending on the number of recesses 44 of the hinge track 42, the leg rest portion 30 can be effectively locked at different angular positions.

In Figures 6a-b, the hinge track 42 having a cam-shaped profile comprises one recesses 44, which is best seen in Figure 6b. This recess 44 is associated with the upper resting position 34, as the hinge track 42 only comprises one single recess 44. As seen in the figures, the recess 44 is located, or formed, along the first side 45 of the hinge track 42 (i.e. the right side of Figure 6b, as indicated by the dashed intersecting line). Moreover, the surface of the second side 46 of the cam-shaped hinge track 42 is a surface being substantially planar (i.e. the left side of Figure 6b, as indicated by the dashed intersecting line). Hence, upon the leg rest portion 30 being affected by a load, such as a user’s legs, the shaping of the first side 45 of the cam-shaped hinge track 42 causes a spring-load on the associated projecting guide knob 53 and thereby forces it to be maintained in the corresponding recess 44. As such, one-way locking of the projecting guide knob 53 is achieved and the leg rest portion 30 is being maintained in the corresponding resting position while a load is affecting the leg rest portion 30.

For embodiments wherein the hinge track 42 comprises an arbitrary number of recesses 44, each additional recess 44 is being formed on the first side 45 of the cam shaped hinge track 42. Moreover, each additional recess 44 is associated with a corresponding intermediate position 33. The second side 46 of the cam-shaped hinge track 42 is preferably having a substantially planar shape, no matter how many recesses 44 are being formed on the first side 45.

By way of example, a sequence of movements of the projecting guide knob 53 will now be explained with reference to Figure 6b. The following given example is, by no means, to be construed as a limiting embodiment. Rather, the sequence of movements may be equally suitable for other embodiments having other types of hinge track 42 structures, such as e.g. additional recesses 44.

The dashed circles indicate three different positions 43 a, 43b and 43 c of the projecting guide knob 53 which are relevant for this particular example. The directional arrows extending from one position to another in one direction indicate the movement of the projecting guide knob 53 along the hinge track 42. The first position 43a corresponds to the lower end position 32, the second position 43b corresponds to the upper resting position 34, and the third position 43c corresponds to an upper end position 36. The cam-shaped hinge track 42 enables the projecting guide knob 53 to be guided starting from the first position 43a, to the second position 43b, to the third position 43c, and then finally back to the first position 43a, in sequence and in one direction. Firstly, the projecting guide knob 53 is guided from the first position 43a to the second position via the first side 45 of the cam-shaped hinge track 42, i.e. the side having a recess 44. Once the projecting guide knob 53 has reached the second position 43b, i.e. the recess 44, the projecting guide knob 53 may be positioned thereby by e.g. applying a load atop of the leg rest portion 30.

The projecting guide knob 53 is then to be guided towards the third position 43c, still along the first side 45, by e.g. a partly circular sweeping motion being applied to the pivoting portion 50. At the third position 43c, the projecting guide knob 53 has been guided past the recess 44 being associated with the upper resting position 34. Moreover, the projecting guide knob 53 has been disengaged from the first side 45 of the hinge track 42 and engaged with the second side 46 of the hinge track 42. Upon the projecting guide knob 53 having reached the third position 43c, the pivoting portion 50 and thus the leg rest portion 30 may be detached from the seat portion 20 simply by applying a pulling force thereto. Hence, upon the leg rest portion 30 being positioned in the upper end position 36, the pivoting portion 50 is detachable from the seat portion 20. Moreover, the pivoting portion 50 and thus the leg rest portion 30 may, in a similar but opposite fashion, be attached to the seat portion 20 once again. Upon attachment, the projecting guide knob 53 will be positioned approximately at the third position 43c. Hence, the third position 43c, i.e. the position corresponding to the upper end position 36, may be interpreted as a position wherein the leg rest portion 30 is positioned vertically above the upper resting position 34.

Upon the projecting guide knob 53 having reached the third position 43c, movement thereof is freely allowed along the second side 46 of the cam-shaped hinge track 42, i.e. the side not having any recess 44, by applying a load atop of the leg rest portion 30. The term “Freely” is in this sense referring to that movement of the leg rest portion 30 will not be prohibited at either one of the upper resting position 34 or at any of the intermediate positions 33 during movement from the upper end position 36 to the lower end position 32. Alternatively, the gravitational force may simply cause this guiding without necessarily applying a manual load on the leg rest portion 30. This movement achieved thanks to the shape of the second substantially planar side 46 of the cam-shaped hinge track 42 that allows for the projecting guide knob 53 to be guided back towards the first position 43a without the projecting guide knob 53 being maintained in a resting position along the way.

It is realized that, as long as the projecting guide knob 53 is being guided along the second side 46 of the cam-shaped hinge track 42, the leg rest portion 30 is freely movable back and forth between the lower end position 32 and the upper end position 36 without stopping at the upper resting position 34 and/or any intermediate position 33. The same is, for reasons which have been presented in this disclosure, not possible upon the projecting guide knob 53 being guided along the first side 45 due to the one or more recesses 44 being formed therealong. Figures 7a-b illustrate a schematic upper front view of a chair 100 comprising a leg rest assembly 10 according to one embodiment. Herein, the hinge mechanism 40 is arranged at the seat portion 20, and the leg rest portion 30 is connected to the hinge mechanism 40 via the pivoting portion 50.

As indicated by the horizontal arrows of Figure 7b, it is understood that the first pivoting arm 51 of the pivoting portion 50 is movable in a horizontal direction while at the same time being maintained in the space defined by the receiving slot 47a of the hinge mechanism 40. Hence, the projecting guide knob 53 being arranged at the associated hinge track 42 will be guided therealong in accordance with the present disclosure. The invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims.