Bath tub lifter

1. A bath tub lifter, comprising

a seat element,

a lifting apparatus for raising and lowering the seat element between a lower operating end position and an upper operating end position, and

a scissor lift arrangement having two pairs of scissor lifts each comprising an inner scissor element and an outer scissor element,

wherein, in an operative state, the inner and outer scissor elements are coupled to each other such that they are mutually pivotable about a bearing axis,

wherein the inner scissor element comprises a bearing inner element,

wherein the outer scissor element comprises a bearing outer element,

wherein the bearing inner element and the bearing outer element are configured such that, when the inner scissor element and the outer scissor element are in an assembly angular position relative to each other, said bearing inner and outer elements can be joined in a radial direction into a functional setting, in which the bearing inner element and the bearing outer element are oriented coaxially to the bearing axis, and

wherein the bearing inner element and the bearing outer element are further configured such that, in the operative state, when the inner scissor element and the outer scissor element are in an angular position relative to each other that differs from the assembly angular position, the inner and outer scissor elements cannot be separated in the radial direction due to form closure over an operating range between the lower operating end position and the upper operating end position.

2. The bath tub lifter as claimed in claim 1 ,

wherein the bearing outer element is configured with a bearing sleeve having a bearing seat, arranged concentrically to the bearing axis, and first and second radial recesses of different tangential width,

wherein the tangential width of the first recess corresponds to a diameter of the bearing seat, and the tangential width of the second recess is smaller than the tangential width of the first recess,

wherein the bearing inner element is configured with a bearing journal, an outer diameter of which corresponds to the diameter of the bearing seat and which has at least one stop cam,

wherein, when the inner scissor element and the outer scissor element are in the assembly angular position relative to each other, the at least one stop cam can pass through the second recess and

wherein, throughout the operating range, when the inner and outer scissor elements are in an angular position relative to each other that differs from the assembly angular position the at least one stop cam cannot exit through the second recess due to form closure.

3. The bath tub lifter as claimed in claim 2 , wherein the bearing outer element is configured with a journal arranged concentrically to the bearing axis, wherein the journal is divided by a journal groove into two opposite journal segments, and the width of the journal groove corresponds to the width of the at least one stop cam.

4. The bath tub lifter as claimed in claim 2 ,

wherein the bearing outer element is configured with a locking cam, which extends from the bearing seat radially in the direction of the bearing axis, and

wherein the bearing journal has a turned groove, in which the locking cam engages when the bearing outer element and the bearing inner element are arranged coaxially to each other.

5. The bath tub lifter as claimed in claim 1 , wherein the two outer scissor elements each have a bearing outer element, and the two inner scissor elements each have a bearing inner element.

6. The bath tub lifter as claimed in claim 1 , wherein the two outer scissor elements are combined to form an outer frame, and the two inner scissor elements are combined to form an inner frame.

7. The bath tub lifter as claimed in claim 6 , wherein the inner frame has at least one cross strut, which connects the two inner scissor elements.

8. The bath tub lifter as claimed in claim 7 , wherein the cross strut is located in the region of the bearing axis.

9. The bath tub lifter as claimed in claim 6 , wherein the outer frame has stiffening corners.

10. The bath tub lifter as claimed in claim 1 ,

wherein the bearing inner element is configured in one piece with said inner scissor element,

wherein the bearing outer element is configured in one piece with said outer scissor element, and

wherein the inner and outer scissor elements are made from injection-molded plastic.

11. The bath tub lifter as claimed in claim 2 , wherein the bearing journal has two stop cams.

12. The bath tub lifter as claimed in claim 3 ,

wherein the bearing outer element is configured with a locking cam, which extends from the bearing seat radially in the direction of the bearing axis, and

wherein the bearing journal has a turned groove, in which the locking cam engages when the bearing outer element and the bearing inner element are arranged coaxially to each other.

13. The bath tub lifter as claimed in claim 2 , wherein the two outer scissor elements each have a bearing outer element, and the two inner scissor elements each have a bearing inner element.

14. The bath tub lifter as claimed in claim 3 , wherein the two outer scissor elements each have a bearing outer element, and the two inner scissor elements each have a bearing inner element.

15. The bath tub lifter as claimed in claim 4 , wherein the two outer scissor elements each have a bearing outer element, and the two inner scissor elements each have a bearing inner element.

16. The bath tub lifter as claimed in claim 2 , wherein the two outer scissor elements are combined to form an outer frame, and the two inner scissor elements are combined to form an inner frame.

17. The bath tub lifter as claimed in claim 3 , wherein the two outer scissor elements are combined to form an outer frame, and the two inner scissor elements are combined to form an inner frame.

18. The bath tub lifter as claimed in claim 4 , wherein the two outer scissor elements are combined to form an outer frame, and the two inner scissor elements are combined to form an inner frame.

19. The bath tub lifter as claimed in claim 5 , wherein the two outer scissor elements are combined to form an outer frame, and the two inner scissor elements are combined to form an inner frame.

20. The bath tub lifter as claimed in claim 7 , wherein the outer frame has stiffening corners.