DE1430765C - Device for stepless pivoting of the backrest of a seat, especially for motor vehicles - Google Patents

Description

The invention relates to a device for continuously pivoting the backrest of a Seat, in particular for motor vehicles, with a hydraulically acting, one cylinder and one double-sided actuated piston with piston rod existing actuating element, one part of which on the backrest and its other part is hinged to a fixed component, the two working spaces of the cylinder of the actuating element over Lines are connected to a spring-loaded pressure fluid expansion tank and in one of these Lines a manually operable, spring-loaded valve is arranged.

In the known devices of this type, one is arranged on a continuous piston rod Piston provided, this piston being one in the sense of the forward pivoting of the backrest onerous return spring designed as a helical spring and the adjusting piston of the pressure medium expansion tank a loading spring also designed as a helical spring is assigned. This well-known The device is therefore complex in its structure and due to the given with springs Risk of breakage prone to failure.

In contrast, the invention is based on the object of providing a device of the type mentioned at the beginning Art to create that is simply structured and less prone to failure is.

The invention is accordingly to be seen in the fact that the piston of the actuating element as known per se Differential piston is formed and the line containing the valve through the larger effective piston area limited working space of the cylinder is assigned. This will make the structure the device is simple, since apart from the valve spring no further helical springs are necessary.

Another advantage results from the fact that a gas spring is installed in the expansion tank in a manner known per se is provided.

The invention is described below on the basis of an exemplary embodiment shown in the drawing explained in more detail.

In the illustrated, a seat cushion 3 and a backrest 4 having motor vehicle seat Backrest 4 can also be pivoted about an axis 5

ίο connected to the frame of the seat cushion 3. Laterally offset to the axis S, the piston rod 7 of a hydraulically acting actuating element 8 is articulated on a lower end part 6 of the backrest 4. The piston rod 7 carries a at its free end

is piston 9, which is in a on the frame of the seat cushion 3 articulated cylinder 10 guided and close to the inwardly curved seat cushion cover or within of the seat cushion 3 is arranged.

Furthermore, a 3 is on the frame of the seat cushion

ao a loaded by a gas spring 15 piston 16 containing pressure medium compensation tank 13 ^ attached. The two chambers formed by the piston 9 10 'and 10 "of the cylinder 10 sin & via flexible lines 11 and 12 with the interior 13' of the Pressure fluid expansion tank 13 connected, the connection between the chamber 10 'and the Interior 13 'takes place immediately, while in the connection between the chamber 10 "and the interior 13 'a valve 14 arranged on the end face of the pressure medium expansion tank 13 is switched on is. The under the tension of a spring 17 valve body 14 'of this valve 14 is on a Hand lever 18 is articulated and, in the rest position, closes a flexible line with its valve head 11 with the interior 13 'connecting opening.

The mode of operation of the device according to the invention is as follows: If the hand lever 18 against If the tension of the spring 17 is actuated in the direction of the arrow 19, this flows in the interior 13 'of the pressure medium expansion tank 13 located pressure medium through the opening released by the valve body 14 'into the Pipeline 11 and thus into the cylinder space 10 ″ of the actuating element 8. The through the different Differential pressure generated by the surfaces of the piston 9 causes the piston rod to move 7 in the direction of arrow 20, whereby the backrest 4 is pivoted about the axis 5 forwards. When the hand lever 18 is released, the valve body 14 'is back on its by the spring 17 Sealing seat pressed so that the pressure medium circuit is interrupted. The backrest 4 then remains immovable in the set position.

In order to be able to pivot the backrest 4 backwards, the hand lever 18 and are also operated exerts slight pressure on the backrest with your hand or back. This swings like that backwards until the hand lever 18 is released.

It goes without saying that this can prevent the backrest 4 from twisting during the pivoting movement to avoid a further actuating element 8 arranged on the other side of the seat cushion 3 its cylinder chambers also via flexible pipelines with the pressure medium expansion tank 13 are connected.

1 sheet of drawings

Claims (2)

Patent claims: 1. Device for stepless swiveling of the backrest of a seat, especially for motor vehicles, with a hydraulically acting cylinder and a cylinder that can be acted upon on both sides Piston with piston rod existing actuating element, one part of which is on the backrest and the other part of which is articulated to a fixed component, the two working spaces of the cylinder of the actuating element are connected via lines to a spring-loaded pressure fluid expansion tank and in a manually operable, spring-loaded valve is arranged on one of these lines, thereby characterized in that the piston (9) of the actuating element (8) as known per se ■ Differential piston is formed and the line (11) containing the valve (14) through the larger effective piston area is assigned to a limited working space (10 ") of the cylinder. 2. Apparatus according to claim 1, characterized in that in a known manner in A gas spring (15) is provided for the expansion tank (13).