Hydraulically damping spring device

Claim 1

A hydraulically damping rubber spring device usable as an engine mount for motor vehicles, comprising: two end walls lying opposite one another in an axial direction of the spring device and between which are arranged two working chambers; both working chambers are fillable with damping fluid and are separated from one another by a dividing wall in which is arranged a channel; said channel connecting the two working chambers to one another; the length of said channel being at least equal to the length of the dividing wall and the cross-section of the channel being small relative to its length; a rubber-elastic spring element adjoining one of the two working chambers and secured on one end wall; means for varying the size of a wall area and a volume of the channel by complete or partial isolation of a longitudinal portion of the channel from outside the spring device; said means for varying including a rotary slide arranged in the channel and transverse to it; rotation means to rotate the rotary slide so that a first longitudinal portion of the channel, which is open towards the second of said working chambers is, in one end position of the rotary slide, connected to another longitudinal portion of the channel, which is open towards the one working chamber; and wherein in the other end position of the rotary slide, the first longitudinal portion of the channel is connected directly to the one working chamber, by-passing the other longitudinal portion of the channel; and wherein between these two end positions of the rotary slide, the first longitudinal portion of the channel is connected to both the one working chamber and the other longitudinal portion of the channel with continuously varying rotary slide passage cross-sections.