US 3535716 A
Description (OCR text may contain errors)
0. GREINER Oct. 27, 1970 USE OF SWING ABSORBERS IN BEDS WITH ADJUSTABLE BACK Filed D60. 4, 1967 InventorzOtto Greiner United States Patent US. Cl. 66 1 Claim ABSTRACT OF THE DISCLOSURE The use of motion decelerators in combination with an adjustable back in a bed which can be adjusted by the users shifting his body-weight.
Beds with adjustable backs where the user can freely and without assistance move the back up or down by transmission of his body weight and can lock it in any position by means of a brake, present the following danger if they are manipulated incorrectly.
If the user moves from the lying into the sitting position without previously having released the brake, the back cannot follow his movement and springs upwards against the users back if the brake is subsequently released. The same happens if the brake is released without anybody lying on the bed, since the movement of the back depends upon the transmissioin of weight from the seat to the back and vice versa, and since the weight of the seat alone is sufiicient to cause the back to move upwards.
This undesirable upward swinging movement can be prevented by employing swing absorbers, that is devices which have little braking action when the movement is slow, but exert proportionally increasing braking action with increasing speed of movement.
In the present case one or more unilaterally acting, hydraulic shock absorbers are used, which are extended when the back swings upwards and exert the braking action mentioned above, but exert no such action if the movement is reversed.
FIGS. 2 and 1 show two examples.
FIG. 1 shows the arrangement of two swing absorbers on a normal hospital bed. For the sake of clarity, the spring covering and the locking device have been omitted.
FIG. 2 shows a section cm. in front of the longitudinal axis of the bed on a larger scale, using one swing absorber.
The bed (FIG. 1) with the usual mobile base and toothed members to regulate the height of the foot end, has a lying surface frame 1 comprising a movably attached back 2. The device effecting the state of balance between seat and back and permitting the user to assume any posture from the lying to the sitting position, consists of the support combination formed by the two-armed lever 3 with bar 4. In order to prevent any undesired sudden upward swinging movement of the back if the bed is manipulated incorrectly, the upper end of a known swing absorber 5 is movably connected to each of the two side bars of the back, whereas its lower end is movably attached to the side bar 7 of the mobile base. If only one swing absorber (FIG. 2) is used, it upper end 6 is movably connected to a cross bracket 9 of the back and the lower end is movably connected between clips 11 attached to a cross bracket 10 of the seat frame 1.
The cross brackets 9 and 10 also serve to receive the locking device for the back, whereby a bow-shaped member 12 can be locked via an eccentric tappet 13 in the trapeze-shaped recess of a plate and released via the lever 15.
The arrangements shown are only examples. It is also possible to attach several swing absorbers between the cross brackets of the back and the extended seat, or only one absorber between the back and the base or a normal bed frame with side walls.
1. In beds where the back can be moved by transmission of the users body-weight into any angle of inclination between the lying and sitting positions and can be locked in any of these positions, the use of a device to prevent any sudden undesired upward swinging movement of the back, consisting of one or more known motion decelerator the upper ends of which are movably attached to the back, their lower ends being connected to a rear extension of the seat or to a firm bed frame or a base.
References Cited UNITED STATES PATENTS 3,190,695 6/1965 Jacobi 297-426 2,639,913 5/ 1953 Reynolds 297-216 X 2,943,866 7/1960 Witter 297-216 X 3,061,843 11/ 1962 Singer et al 566 3,253,285 5/ 1966 Fox 567 3,268,256 8/1966 Blank 297--216 3,283,342 11/1966 Pankert 566 3,319,270 5/1967 Greiner 566 3,353,193 11/1967 Greiner 566 CASMIR A. NUNBERG, Primary Examiner US. Cl. X.R. 29729, 320