BATH TUB LIFTING DEVICE

Abstract: In a bath tub lifting device operated by a jack (20), the jack is unloaded by a so-called gas spring (32).

Description: - Λ - Bath tub lifting device The invention refers to a bath tub lifting device comprising a jack to raise and lower a bath tub. Such a lifting device, which is known through e.g. U.S. patent No. 3,889,304, is intended to make bathing of a patient easy, a lowered position of the bath tub facilitating the transferring of the patient to and from the bath tub, respectively, and a raised position facilitating the work for a person who stands beside the bath tub and bathes the patient. At the known lifting device the jack is constituted by a fluid motor dimensioned to lift the entire weight of the bath tub, the bath -water and the patient in the bath tub. Said weight is considerable and a high fluid pressure or a large fluid motor is therefore required. The object of the invention is to substantially reduce the necessary lifting force of the jack thereby simplifying the driving of the lifting device. This object is reached by the bath tub lifting device according to the invention by a so-called gas spring which is arranged to unload the jack. Through the invention the necessary lifting force of the jack can be reduced so that the jack advantageously can be driven by an electric motor without the electric amperage becoming too great. Therfore, according to a further develop¬ ment of the invention the jack is driven by an electric motor. An embodiment of a bath tub lifting device according to the invention will be described in the following with reference to the figure of the accompanying drawing. The numeral 10 designates a lower part which shows a frame 12 resting on a floor 14, and a lower column part 16 on which an upper column part 18 is displaceably journalled in vertical direction. The upper column part 18 is vertical¬ ly adjustable by a jack 20 which is operable by an electric motor 22 driving a longitudinal screw inside the jack. The screw engages a nut connected to a rod 24 of the jack, so that the rod 24 is displaced in its longitudinal direction relative to a lower part 26 of the jack, when the screw rotates. Arms 28 carrying a bath tub 30 are rigidly connected to the upper column part 18. The rod 24 is rigidly connected to the upper column part 18. The lower part 26 of the jack is rigidly connected to the lower part 10. The jack 20 is unloaded by means of a so-called gas spring 32, the one end of which being rigidly connected to the upper column part 18 and the other end of which being rigidly connected to the lower part 10. The gas spring 32, the force of which being substantially constant during the whole stroke of the gas spring as is character- istic for gas springs, is arranged to lift the upper column part with a force which is substantially equal to the weight of the parts (including the bath tub, the bath-water and the patient) of the lifting device, which move in vertical direction together with the upper column part 18. If the bath-water is filled up and emptied, respectively, and the patient is transferred to and from the bath tub, respectively, when the bath tub is located in its lowered position, the jack then substantially only has to be dimensioned to overcome the friction forces which arise, when the bath tub is lifted from the lowered position to the raised position and after that is lowered from the raised position to the lowered position.

Claims: Claims 1. Bath tub lifting device comprising a jack (20) to raise and lower a bath tub (30), characterized by a so-called gas spring (32) which is arranged to unload the jack. 2. Bath tub lifting device according to Claim 1, characterized in that the jack is driven by an electric motor (22).

Inventors: EKMAN LARS GUSTAF, EKMAN, LARS, GUSTAF
Applicants: ELECTROLUX AB, AKTIEBOLAGET ELECTROLUX
Application year: 1987
Main classification: A47K3
IPC codes: A61G7