Shock absorber arrangement

Claim 2

Arrangement for bringing about in a shock absorber different kinds of damping characteristics, which are determinable with controls (I), independently of variations in any parameter(s), the piston speed for example, which seek to change the set damping effects in undesirable manner, in which connection the shock absorber comprises a piston/piston rod working in a medium in the cylinder of the shock absorber and works with a servo function, in which a first valve element (7) carries out determination of the size of a restriction (7f) in a principal medium flow between the upper and lower sides (1a, 1b) of the piston depending on a first pressure (P′) produced by means of a pilot flow running between the aforementined upper and lower sides which is determinable with a second valve element (8) controllable by the aforementioned controls, characterized in that the first valve element (7) comprises a member, preferably in the form of a movable slide, the position of which is in every instance of control counterbalanced by the aforementioned first pressure (P′) and a second pressure (P˝) originating from the pressure differnece (P1-P2 or P2-P1) existing between the upper and lower sides of the piston, and in that the second valve element (8) includes or interacts with a proportional magnet (13) which influences, for example holds constant, the first pressure (P′) independently of the aforementioned variation.

Claim 3

Arrangement according to claim 1, characterized in that an integral part of the counterbalancing function of the member/slide is a spring (10), the spring force (F‴˝) of which acts on the the member/slide in the same direction as a first force (F′) caused by the first pressure (P′), in which connection the position of the member/slide is counterbalanced by a force, which is composed of the aforementioned spring force and the first force, and a second force (F˝) which is caused by the second pressure (P˝).

Claim 4

Arrangement according to claim 1 or 2, characterized in that the member/slide is exposed to the first and second pressures (P′, P˝) via its end surfaces (7a or 7b respectively) and is provided with a lateral recess (7e) for conduct of the principal medium flow.

Claim 5

Arrangement according to any of claims 1, 2 or 3, characterized in that the slide is provided with a channel (7c, 7d) which connects the pressure spaces (V1, V2) for the first and second pressures and via which the aforementioned pilot flow runs in the respective direction from the pressure space (V2) for the second pressure, to the pressure space (V1) for the first pressure.

Claim 6

Arrangement according to any of the previous claims, characterized in that the second valve element (8) works towards a seat (9a) in a passage (9b) between the pressure space for the first pressure and a further space (V3) which is connected via first and second check valves (18a, 18b) with the upper and lower sides of the piston respectively.

Claim 7

Arrangement according to any of the previous claims, characterized in that the space (V2) for the second pressure (P˝) is connected with the upper and lower sides of the piston via third and fourth check valves (18c, 18d).

Claim 8

Arrangement according to any of claims 5 or 6, characterized in that a pilot flow running from the upper side of the piston to its lower side acts via the third check valve (18c), the channel (7c, 7d) in the member/slide, the seat passage (9a) and the second check valve (18b) and in that a pilot flow running from the lower side of the piston to its upper side acts via the fourth check valve (18d), the channel in the member/slide, the seat passage and the first check valve (18a).

Claim 9

Arrangement according to any of the previous claims, characterized in that a control/electric control signal (I) supplied to the proportional magnet (13) brings about an acting armature force/third force (F‴) in the armature (13a) of the proportional magnet, which third force is directed towards a fourth force (F˝˝) caused by the pilot flow on the second valve element (8), in which connection the pilot flow is counterbalanced by the first pressure and the second element is pressed towards the pilot flow at the seat by the armature force.

Claim 10

Arrangement according to any of the previous claims, characterized in that uniform damping characteristics are obtained within the whole adjustment range which is large with regard to the piston speed parameter, 0.05-4.00 m/sec for example.

Claim 11

Arrangement according to any of the previous claims, characterized in that it is controllable by means of a comparatively simply constructed control unit which is preferably arranged for stepless control within the adjustment range.

Claim 12

An arrangement operating as an amplifier and forming part of a shock-absorber, by means of which arrangement the shock-absorbing capacity of the shock-absorber is variable with the help of electrical control signals from a control unit, and comprising a first variable restriction for a principal fluid flow between the upper and lower sides of a piston forming part of the shock-absorber, a unit, for example a membrane, a spring-loaded piston device, etc, which determines the size of the first restriction with the help of a pressure acting on one side of the unit and generated by a pilot fluid flow between the aforementioned upper and lower surfaces, and a control device capable of being actuated by means of the control signals which, by the actuation of a second variable restriction, determines the size of the pilot fluid flow, characterized in that the control device consists of a proportional magnet which is executed with a valve element which operates against a seat included in the second restriction, via which the pilot fluid flow passes and in so doing creates a force acting counter to the force which is determined by the control signal of the valve element, and where the position of the valve element is capable of being determined with the counter-acting force, in order, for each control signal setting, to make the counter-acting force independent of, or dependent in a predetermined fashion on the position of the valve element, in conjunction with which the aforementioned self-regulating function of the proportional magnet is capable of being transmitted through a corresponding effect on the aforementioned pressure to the amplifier/servo function of the shock-absorber, in so doing counteracting any increase in the difference in presure between the aforementioned upper and lower sides due to a variation in a shock-absorber parameter, for example the piston speed, such as to produce an undesired disproportionate fluctuation in the principal fluid flow/damping.

Claim 13

An arrangement operating as an amplifier and forming part of a shock-absorber, by means of which arrangement the shock-absorbing capacity of the shock-absorber is variable with the help of electrical control signals from a control unit, and comprising a first variable restriction for a principal fluid flow between the upper and lower sides of a piston forming part of the shock-absorber, a unit, for example a membrane, a spring-loaded piston device, etc, which determines the size of the first restriction with the help of a pressure acting on one side of the unit and generated by a pilot fluid flow between the aforementioned upper and lower surfaces, and a control device capable of being actuated by means of the control signals which, by the actuation of a second variable restriction, determines the size of the pilot fluid flow, characterized in that the control device consists of a proportional magnet which is executed with a valve element which operates against a seat included in the second restriction, via which the pilot fluid flow passes and in so doing creates a force acting counter to the force which is determined by the control signal of the valve element, and where the position of the valve element is capable of being determined with the counter-acting force, in order, for each control signal setting, to make the counter-acting force independent of, or dependent in a predetermined fashion on the position of the valve element, in conjunction with which the aforementioned self-regulating function of the proportional magnet is capable of being transmitted through a corresponding effect on the aforementioned pressure to the amplifier/servo function of the shock-absorber, in so doing counteracting any increase in the difference in presure between the aforementioned upper and lower sides due to a variation in a shock-absorber parameter, for example the piston speed, such as to produce an undesired disproportionate fluctuation in the principal fluid flow/damping.

Claim 14

Arrangement according to Patent Claim 11, characterized in that the proportional magnet (23) for each control signal value (i₁, i₂, i₃) maintains the aforementioned pressure at a constant level.