GB2149294A - Chair lift - Google Patents

Abstract

The chair lift is a chair designed to assist physically handicapped persons moving down to, and arising from a sitting position. The movable seat and arms are hinged at the front of the base. The lifting mechanism comprises a cam arrangement driven by a D.C. electrical motor. <IMAGE>

Description

SPECIFICATION Chair lift "Chair Lift" has been designed to help physically handicapped people who find difficulty in sitting and standing.

The chair consists of (see Fig. 1) No. 1 The Back, attached to a hollow base No. 2, with a seat No. 3, hinged to the base No. 2 at No.

3A and No. 3B. To the right of the seat No. 3 and attached to the base No. 2, is the control arm No. 4, which is pivoted to the base at 4A, jointed at 4B and pivoted to the seat at 4C. The control box, No. 5, is fixed to the end of the arm (a description of its function appears in the operation section).

Inside the base No. 2 are installed, (see Fig.

2) two 1 2 volt car batteries connected in series, No. 6; a D.C. motor, No. 7; a 500-1 ratio gear box, No. 8; a shaft with two or more cams (the cams are shaped so that the load on them follows the cosine function i.e.

maximum at 0" and minimum at 90"), No. 9; cam guides are fitted to the base of the seat, No. 10; a limit switch is situated next to the right hand cam, No. 11; and there are two actuating lugs on the cam at 1 1 A and 11 B.

''CHAIR LIFT" OPERATION 1. To operate the Chair from the sitting to the standing position: First on the control box, the ganged cut off switch and field switch (see circuit diagram) are set to the "up" position. This selects the field on the D.C. motor to rotate the shaft and cams clock-wise. To start the motor a spring loaded switch is depressed completing the circuit. The motors runs until the actuating lug (11A) trips the limit switch (11) or if the pressure is released from the spring loaded start switch.

2. To operate the Chair from the standing to sitting position: The ganged switch is set to the "down" position and when the spring loaded start switch is depressed. The motor reverses and the cams rotate anti-clockwise until the lug 11 B trips the limit switch 11, or if pressure is released from the start switch.

Figure shows the Chair down; Figure 2 shows the Chair in the "up" position.

1. The chair lift is a chair whoose seat and arms are rotated from horizontal to 70 via electrically driven cams.

2. The seat and arms, as claimed in 1, are connected to the rest of the chair by a hinge at the front.

3. The cams, as claimed in 1, are shaped so they rotate the chair at a constant rate 4. The cams, as claimed in 1, are attached to the driving shaft, are driven via a reduction gear by an electric motor.

5. The electric motor, as claimed in 4, is a 1 2 volt shunt D.C. motor with reversable field switching.

6. The electric motor, as claimed in 4 and 5, is powered by two 1 2 volt car batteries connected in series.

7. The range of movement of the cams, as claimed in any previous claim, is determined by limit switches.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (7)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Chair lift "Chair Lift" has been designed to help physically handicapped people who find difficulty in sitting and standing. The chair consists of (see Fig. 1) No. 1 The Back, attached to a hollow base No. 2, with a seat No. 3, hinged to the base No. 2 at No. 3A and No. 3B. To the right of the seat No. 3 and attached to the base No. 2, is the control arm No. 4, which is pivoted to the base at 4A, jointed at 4B and pivoted to the seat at 4C. The control box, No. 5, is fixed to the end of the arm (a description of its function appears in the operation section). Inside the base No. 2 are installed, (see Fig. 2) two 1 2 volt car batteries connected in series, No. 6; a D.C. motor, No. 7; a 500-1 ratio gear box, No. 8; a shaft with two or more cams (the cams are shaped so that the load on them follows the cosine function i.e. maximum at 0" and minimum at 90"), No. 9; cam guides are fitted to the base of the seat, No. 10; a limit switch is situated next to the right hand cam, No. 11; and there are two actuating lugs on the cam at 1 1 A and 11 B. ''CHAIR LIFT" OPERATION 1. To operate the Chair from the sitting to the standing position: First on the control box, the ganged cut off switch and field switch (see circuit diagram) are set to the "up" position. This selects the field on the D.C. motor to rotate the shaft and cams clock-wise. To start the motor a spring loaded switch is depressed completing the circuit. The motors runs until the actuating lug (11A) trips the limit switch (11) or if the pressure is released from the spring loaded start switch. 2. To operate the Chair from the standing to sitting position: The ganged switch is set to the "down" position and when the spring loaded start switch is depressed. The motor reverses and the cams rotate anti-clockwise until the lug 11 B trips the limit switch 11, or if pressure is released from the start switch. Figure shows the Chair down; Figure 2 shows the Chair in the "up" position. CLAIMS

1. The chair lift is a chair whoose seat and arms are rotated from horizontal to 70 via electrically driven cams.

2. The seat and arms, as claimed in 1, are connected to the rest of the chair by a hinge at the front.

3. The cams, as claimed in 1, are shaped so they rotate the chair at a constant rate

4. The cams, as claimed in 1, are attached to the driving shaft, are driven via a reduction gear by an electric motor.

5. The electric motor, as claimed in 4, is a 1 2 volt shunt D.C. motor with reversable field switching.

6. The electric motor, as claimed in 4 and 5, is powered by two 1 2 volt car batteries connected in series.

7. The range of movement of the cams, as claimed in any previous claim, is determined by limit switches.