Prior-Art Technique Many different types of patient chairs are known.

Some of them are commonly mechanical, others are in a complicated way fitted with electronics for raising and lowering the seat, inclination backwards, inclination of leg rest etc. Some of them have the convenience of the 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 mecha- nical patient chairs. Many patients are incapable of com- municating their needs or wishes or discomfort to their carers.

One component of patient chairs which has not yet achieved a satisfactory function and handleability, either from the carer's or from the patient's point of view, is the leg rest especially in mechanical patient chairs. These leg rests often 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 com- ponent for both feet) must be dismounted. Especially in mechanical patient chairs, they have only one use posi- tion, corresponding to a normal sitting position of an "average"patient, supporting one or both legs of the

patient, causing stasis in other patients. 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 posi- tion of the legs is arranged. Any possibility of dis- mounting is merely occasionally used by carers, since dismounting and subsequent mounting is considered diffi- cult 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 carer if the patient himself is incapable of raising his legs, thus facilitat- ing 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 ergonomical- ly unsatisfactory position. The leg supports 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, but 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, which 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.

Objects of the Invention An object of the invention is to provide a calf rest construction for a patient chair, which is simple and thus can be manufactured at low cost, said calf rest construction having an inactive position where it takes up a small space on the patient chair and thus need not be removed when moving the patient chair to narrow spaces, and having an active position supporting a patient's legs in a raised position. Another object is

that the calf rest construction should be detachable from the patient chair, if the option of detachment should be considered important.

Summary of the Invention The objects are achieved by a calf rest for a patient chair according to independent claim 1. Advan- tageous embodiments have the features stated in the dependent claims.

Embodiments, Drawings An embodiment of the invention will now be describ- ed in more detail with reference to the accompanying drawings.

Fig. la shows a patient chair with a calf rest in an inactive position.

Fig. 1b shows the patient chair in Fig. 1 (on a slightly different scale and with the entire back of the chair) with the calf rest in an active position.

Figs lc-f illustrate a sequence of movements of the calf rest between an inactive and an active position.

Fig. 2 shows a calf rest mounting arm partly in per- spective, partly in cross-section.

Fig. 3a is a perspective view of a loose fastening pin which is fixed to the underside of the patient chair.

Fig. 3b is a side view of the fastening pin.

Fig. 3c is a cross-section along line A-A in Fig. 3a.

Fig. 3d illustrates a groove shown in Figs 3a-c in an extended state and on a larger scale.

Reference is made to Fig. la, which illustrates part of a patient chair 1 which is the subject matter of a Swedish patent application filed simultaneously herewith.

The patient chair 1 has a chassis 2, with a frame 3 and a substantially vertical, vertically arched stand 4. The stand 4 is connected to a unit 5 of seat and back 6,7 by means of a roller bearing arrangement 8 which is attached to the unit 5 and adapted to roll on the stand 4. Thus the unit 5 is movable on the stand 4, following the arc

shape thereof. The movement can be effected in various ways, using hand power acting on a winch, or using an electric pneumatic motor, etc. acting between the chassis 2 and the unit 5. In Figs la, lb, a motor 9 and a trans- mission 10 for the roller bearing arrangement 8 are indi- cated.

A calf rest 20 according to the invention is mount- ed on the patient chair 1. The calf rest 20 comprises a mounting arm 21 and, mounted thereon, a plate-shaped calf rest pad 22. The mounting arm 21 has a transverse part 21a at one end and a chair mounting sleeve 21b at the other end. The transverse part 21a forms a hinge pin which cooperates with hinge pin holding elements 23 on the back of the calf rest pad 22, so that the calf rest pad is tiltable on the arm 21, as indicated by the double arrow in Fig. lb.

The chair mounting sleeve 21b is arranged for hinge engagement with a pin-like fastener 24 which is fixed to the underside of the seat 6 close to the front edge thereof and close to a corner thereof.

In Fig. la, the calf rest is in an inactive, non- calf-supporting moved-away end position. The moved-away position is used, for instance, while a patient is made to sit in the patient chair by carers, when transporting or storing the patient chair without a patient, or when transporting a patient in narrow spaces.

In Fig. lb, the calf rest is in an active position, which is the other end position of the calf rest, sup- porting an extended leg of a patient sitting in the patient chair.

As is evident from Fig. la, the extent of the calf rest pad 22 in the inactive position is essentially parallel to the patient chair side, i. e. its major parts are essentially parallel to the vertical and horizontal direction of the patient chair 1, and the calf rest pad 22 is positioned quite close to the seat 6, the mounting arm 21 extended between the seat 6 and the calf rest pad

22. This means that, in the inactive position, the calf rest 20 takes up a minimum space on the patient chair 1, seen in the transverse direction thereof.

The arrangement is such that a movement between the active and inactive positions of the calf rest 20 occurs in a single part-circular sweeping motion of the calf rest 20 about the pin fastener 24, so that the calf rest, when approaching the patient's leg (extended vertically in the sitting position) during this sweeping motion (from the inactive position) enters, from the side of the patient's leg, under the leg which is now possibly lifted somewhat by the carer.

To perform such a sweeping motion, the pin fastener 24 on the seat 6 is inclined at a suitable angle. This is evident from Figs lc-f, which illustrate a sequence of movements of the calf rest components 21,22 from said inactive position to said active position.

As is evident from Fig. lb, the mounting sleeve 21b has an internal lug 25. The lug is intended to cooperate, in the course of said motion, with a circumferentially extended guide groove 26 in the pin fastener 24. Blind pockets 25,25', which are substantially perpendicular to this guide groove 26, define said end positions of the calf rest. The pocket 25 corresponds to the inac- tive position, while the pocket 25'corresponds to the active position. In the mounting sleeve 21b there is also a pressure spring 27 to provide automatic insertion (snapping-in) of the lug into the respective pockets 25 when reaching the end positions.

It is noted that the inclination of the pin 24 and the sleeve 21b cooperating therewith automatically results in assistance by gravity to move the calf rest from the inactive end position to the active end posi- tion, implying that the carer need not apply power during the major part of the movement. With a suitable inclina- tion of the hinge arrangement 21b and 24, which a person skilled in the art can easily find based on the teachings

of the invention, the angle a can be about 150° and the angle ß can be about 60°. These angle values are in no way limiting; they depend on the length of the mounting arm 21, which is in turn adjusted to the point on the present patient chair at which the calf rest can be mounted while taking different aspects into considera- tion.

The calf rest 20 can be removed from its fastener 24 in the active position through a third pocket 28 which is perpendicular to the guide groove 26 and which opens in the bottom surface of the fastener 24, see Fig. 3d.

As is evident from that stated above, the calf rest is operated in the following way. With the calf rest 20 in the inactive position (Fig. la), the carer presses the sleeve 21b upwards, against the action of the spring 27, whereby the lug 25 is disengaged from the pocket 25 and can run in the guide groove 26 with a falling motion (see Figs 1c-1f), during which the carer can stop/slow down its movement while the patient's leg is only slightly lifted, so that the calf rest pad can be pivoted inwards sideways behind (under) the patient's calf. In the vici- nity of the active end position, the carer helps the mounting arm and the calf rest pad to enter (snap into, by means of the pressure spring 27) the end position in the pocket 25', Figs lc-f and lb. To perform a return- ing movement to the inactive position, the carer again presses the sleeve 21b upwards, whereby the mounting arm 21 and, thus, the calf rest pad 22 can be pivoted back to the inactive position. To remove the calf rest from its pin fastener 21b and from the patient chair 1, the mount- ing arm 21 is pivoted in the opposite direction, so that the lug 25 is moved to the pocket 28 and can leave this through the opening on the underside of the pin.

It is understood that a mirror-inverted calf rest is located on the other side (not shown) of the patient chair. However, it is possible for a mounting arm 21 to support two calf rest pads, for the patient's left leg

and right leg. The above-mentioned saving of space in the lateral direction of the patient chair is still achieved.

The calf rest 20 has, as is particularly shown in Figs la, 1b and 2, a rotatable ear 29 at the pad end of the mounting arm 21, which serves to lock the calf rest pad in a suitable tilted position relative to the mount- ing arm, which suitable position is selected according to the patient's needs (the leg is more or less inclined).

For adjustment to different patients with different- ly long (lower) legs, the calf rest pad can be provided with spaced-apart hinge holding elements, illustrated by dashed lines 23a, 23b in Fig. 1, for engagement with the transverse part 21b of the mounting arm 21.

Figs la and 1b also illustrate foot rests 30 which are pivotable in their plane sideways, inwards under the seat 5 by means of a hinge 31. Preferably the foot rest is separated from the calf rest, for as much free space as possible to be available under the seat 5.

A patient chair with a vertically adjustable seat has been described above. The calf rest according to the invention has the special advantage precisely in such patient chairs, implying that a raised position of the patient does not require the carer to bend-thus strain- ing his back-to operate the calf rest.

However, the calf rest according to the invention is, of course, usable also for patient chairs that do not have a vertically adjustable seat. The calf rest still has its important advantage of adjustability in a position requiring a small space close to the patient chair. It goes without saying that the calf rest need not be fixed to the seat, but can be fixed to an arbitrary chassis part.

An alternative construction of the calf rest accord- ing to the invention is designed similar to an aircraft table in the front row, where a hinge allows raising of one (rear) edge end of the table leaf arranged with its major parts in a vertical position, about a hinge at the front edge end, and after that lowering of the table leaf, by another hinge, to a horizontal position.