Untitled record

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIGS, la, lb and lc represent diagrammatically the principles of operation of a stretcher according to the invention;

FIG. 2 represents diagrammatically an embodiment tested in practice;

FIG. 3 shows to a larger scale another detail of the embodiment according to FIG. 2;

FIG. 4 shows to a larger scale another detail of the stretcher according to FIG. 2;

FIG. 5 is a perspective view of the stretcher according to FIG. 2;

FIG. 6 is a perspective view of the driving mechanism of the stretcher according to FIG. 2.

DETAILED DESCRIPTION OF SOME EXEMPLARY EMBODIMENTS OF THE INVENTION

The FIGS, la to lc show diagrammatically a possible, simple embodiment of the invention. The idea underlying the invention will be clarified with reference to these figures.

The stretcher according to FIG. 1 consists of a diagrammatically represented frame 1 and a supporting plate 2 fixedly connected therewith. A guide roller 3 for a belt 10 is provided at the front end of the frame 1, and a guide roller 4 for the belt 10 and a travelling roller 5 are provided at the rear end of the frame 1. The travelling roller 5 is driven via the pinion 6 and the crank 7. The frame 1 bears on a surface or ground 8 via the travelling roller 5 and the skate 9 in such a way that the roller 3 is slightly above the ground 8. The endless belt 10 is provided around the guide rollers 3 and 4.

When the travelling roller 5 is driven in the direction of the arrow 11, the roller 4 and consequently the belt 10 will be moved in the direction of the arrow 12. When the rollers 4 and 5 have the same diameter the respective circumferential or linear velocities of the roller 5, the roller 4 and the belt 10 are equal. Upon driving the roller 5, the frame 1 moves rightward in the direction of the arrow 13, and the upper portion of belt 10 moves leftwards with respect to the frame in the direction of the arrow 14 over the supporting plate 2. This means that, when the front roller 3 comes underneath an object 15 to be lifted from the ground 8, this object 15 will be transferred to the supporting plate 2 without its position with respect to the ground 8 being changed. No shift of the belt 10 with respect to the underside of the object 15 occurs; the belt 10 is so to speak “unrolled” underneath the object 15. The object 15 is transferred to the supporting plate 2, the belt 10 serving as an intermediate layer, in exactly the same position as that in which the object 15 and portions thereof were with respect to the ground 8. This means that when the object 15 is a human being, he can be transferred to the stretcher without the position of the body being changed.

FIG. lb shows the situation in which the object 15 is halfway on the supporting plate 2. FIG. lc shows the situation in which the object 15 is entirely on the supporting plate 2. If now the travelling roller 5 is disengaged from the driving guide roller 4, the entire stretcher can be displaced with respect to the ground 8 without the position of the object 15 on the supporting plate 2 being changed. Eventually, the entire stretcher may also be lifted and displaced.

In order to lift the object 15 from the supporting plate 2 the aforementioned movements are reversed.

FIG. 2 shows diagrammatically and schematically a cross-section of an embodiment successfully tested in practice. In this embodiment, an endless belt 19 is used for driving or translating the stretcher.

A supporting belt 10 is guided by a front small guide roller 16, a guide roller 17 situated at the rear end of the stretcher, and a driving roller 18. A traveling belt 19 is guided by a front guide roller 20 and a driving roller 21. Under the supporting belt 10: is a supporting plate 22. Gear wheels 23 and 24 are provided on the axles of the rollers 18 and 21, respectively. The gear wheels 23 and 24 are driven via a chain 25 which is further guided by a tension gear wheel 26 and driven via a gear wheel 27 by means of a crank 28.

The rollers 16, 17, 18, 20 and 21 and the gear wheels 26 and 27 are held in a suitable frame (not shown in this figure) which likewise carries the supporting plate 22. The frame further supports a number of horizontal supporting rollers 29 by which the entire unit bears on the ground.

With reference to FIG. 5, a frame includes two longitudinal girders 30 and 31 in which the supporting rollers 29 are supported. These longitudinal girders 30 and 31 are provided between two other longitudinal girders 32 and 33, respectively, which at their front end carry the guide roller 16. This guide roller 16 is in fact a combination of a number of short individually supported rollers in order to ensure the necessary rigidity.

The longitudinal girders 32 and 33 each carry a fastening plate 34 (see FIG. 6) in which the rollers 18 and 21 are supported. These plates 34 carry furthermore a frame 35 in which the driving gear wheel 27 and the crank 28 are supported. The roller 17 is secured to two sliding pieces 36 and 37 by means of which the supporting belt 10: can be tensioned.

The device operates as follows (see FIGS. 2, 3 and 4).

Upon turning the crank 28 in the direction of the arrow 38, the chain 25 moves in the direction of the arrow 39, the roller 18 moves in the direction of the arrow 40, and the roller 21 moves in the direction of arrow 41. The lower portion of belt 19 moves in the direction of the arrow 42, and the upper portion of belt 19 moves in the direction of the arrow 43. The lower portion of the belt 10: moves in the direction of the arrow 44, and the upper portion of the belt 10: moves in the direction of the arrow 45. It appears that the same movements are brought about as in the embodiment shown in FIGS, la to lc. That is, the entire stretcher moves rightward and, since the diameter of the rollers 18 and 21 is equal and of the gear wheels 23 and 24 is equal, the upper portion belt 10; moves leftward with an equal speed with respect to the frame. Therefore, this effect need not further be described.

The FIGS. 3 and 4 show in an enlarged scale the situation at the rear drive end and at the front end, respectively, of the stretcher. It appears from these figures how the belts 10 and 19 are provided about the guide tollers.

It should be noted that the stretcher may be provided with a liftable wheel system so that a displacement is possible without the traveling belt 19 being in contact with the ground. The stretcher can further be provided with a suitable safeguard structure in order to lift and transport, for example, patients contaminated by radioactivity.