Damping system for a rotating shaft

Claim 2

A damper system adapted to dampen a vibrating body movable on a stationary member, comprising: a damping means for defining an area of a fluid for creating a resistance to a movement of the vibrating body caused by the viscosity of the fluid passing though said area, said fluid being an electro rheological fluid for obtaining a Winslow effect by applying an electric field to the fluid; electrode means arranged in said area for generating such electric field in the area, and; damping control means for controlling the strength of the electric field so that a desired damping characteristic of the damper is obtained within a designated range of frequency of vibration of the vibrating body.

Claim 3

A system as claimed in claim 1, further comprising a spring element arranged parallel to the damper means.

Claim 4

A system as claimed in claim 1 or claim 2, wherein said damping means comprises a casing, a piston connected to the vibrating member to be dampened and movably arranged in the casing, a first chamber formed in the casing on one side of the piston, a second chamber formed in the casing on the other side of the piston, and orifice means located between the first and second chamber for providing said area for creating a resistance to the movement of the piston connected to the vibrating body.

Claim 5

A system as claimed in claim 3, wherein said orifice means comprises at least one opening formed in the piston.

Claim 6

A system as claimed in claim 3, wherein said orifice means comprises an annular slit formed between the casing and the piston.

Claim 10

A system as claimed in claim 8 wherein said calculating means comprises a map of data indicating the damping characteristic to various values of the frequency, and means for calculating, based on the stored data of the damping characteristic, a value of a damping characteristic matching the detected frequency.

Claim 11

A damper system adapted to dampen a vibrating body movable on stationary member, as claimed in claim 1 comprising: a tubular casing; a piston axially slidably arranged in the casing; a first chamber formed in the casing on one side of the piston; a second chamber formed in the casing on the othere side of the piston; electro rheological fluid for obtaining a Winslow effect by applying electric field thereto being filled in the first and second chambers; means for providing at least one orifice for creating a resistance to a movement of the piston caused by a vibration of the vibrating body, which resistance is generated by throttling the fluid passing through the orifice, said orifice defining a pair of opposite surfaces; electrode means arranged in said opposite surfaces of the orifice for creating an electric field directed substantially transverse to the flow of the fluid in the orifice, and; damping control means for controlling the strength of the electric field so that a desired damping characteristic of the damper is obtained within the designated range of frequency of the fibration of the vibrating body.

Claim 12

A damper system as claimed in claim 10, wherein said piston is provided with at least one opening therethrough which defines a pair of facing walls extending axially, and wherein electrode means comprise a pair of electrode platings located on the facing walls, respectively.

Claim 13

A damper system as claimed in claim 10, wherein two diametrically opposite openings are provided in the piston, and the pair of electrode platings are provided on each of the openings.

Claim 14

A damper system as claimed in claim 12, wherein each of said electrode platings extends along the entire length of the opening.

Claim 15

A damper system as claimed in claim 11, where two openings are arranged so as to be dimetrically opposite each other, the pair of the electrode platings being provided on each of the openings.

Claim 16

A damper system as claimed in claim 11, wherein a plurality of angularly spaced and circumferentially extended openings are formed in the piston, and electrode means comprise at least two ring shaped electrodes, and a plurality of angularly spaced insulating blocks, so that a plurality of angularly spaced and circumferentially extended openings are formed between the adjacent blocks, and the facing electrodes in each of the openings are formed by parts of the facing two ring shaped electrode platings.

Claim 17

A damper system as claimed in claim 11, wherein a plurality of angularly spaced and circumferentially extended openings are formed in the piston, and electrode means comprise a plurality of pairs of circumferentially spaced electrodes located adjacent ot each other, and a plurality of spacers located between the adjacent pairs of the electrodes on a circumference of the piston, each of the openings being formed between the facing electrodes.

Claim 18

A damper system as claimed in claim 10, wherein an annular slit is formed between the piston, and wherein electrode means comprises first electrode layer circumferentially arranged on the inner surface of the casing, and second electrode layer circumferentially arranged on the outer surface of the piston.

Claim 19

A damper system as claimed in claim 17, wherein said first electrode layer comprises a circumferentially continuous plating on the casing, and said second electrode layer comprises a circumferentially continous plating on the piston.

Claim 20

A damper system as claimed in claim 18, wherein said plating as the first electrode layer has axially extending projections and recesses arranged alternately in the circumferential direction, and said second electrode layer has axially extending projections and recesses arranged alternately in the circumferential recesses arranged alternately in the circumferential direction, the projections and recesses of the first and second electrode layers being meshed in a gear like manner.

Claim 21

A damper system as claimed in claim 17, wherein said first electrode layer comprises a plurality of angularly spaced strips on the casing, and said second electrode layer comprise a plurality of anguarly spaced strips on the piston, and these strips are arranged to face each other.

Claim 22

A damper system as claimed in claim 17, wherein said piston has at least one opening.

Claim 23

A damper system as claimed in claim 21, wherein said opening defines facing inner sides, and further comprises an auxiliary electrode means having a pair of electrodes on the facing inner sides of the opening.

Claim 24

A damper system as claimed in claim 10, wherein said damping control means comprises means for detecting the frequency of the vibrating body, means for calculating a setting of the damping characteristic in accordance with the detected frequency, and means for controlling the voltage applied to said electrode means to obtain a desired damping characteristic.

Claim 25

A damper system as claimed in claim 23, wherein said calculating means comprises a map of data indicating the damping characteristic as various values of the frequency, and means for calculating, based on the stored data of the damping characteristic, a value of a damping characteristic matching the detected frequency.

Claim 26

A damper system as claimed in claim 1 adapted to dampen a rotating shaft on a stationary body via a rotary bearing assembly, comprising: a support member having an elasticity for connecting the bearing assembly, to the stationary body; an axially extending annular slit formed between the support body and the stationary body for creating a film of an electro rheological fluid to obtain a Winslow effect, means for forcibly introducing the fluid into said annular slit, a chamber opened to the ends of the annular slits for removal of the fluid from the slit; electrode means arranged in said area for generating an electric field in the annular slit across the flow of the fluid in the slot, and; damping control means for controlling the strength of the electric field so that a desired damping characteristic of the damper is obtained within the designated range of frequency of the vibration of the vibrating body.

Claim 27

A damper system as claimed in claim 25, wherein said electrode means comprises an axially extending first annular electrode on the support member, and an axially extending second annular electrode on the stationary member.

Claim 28

A damper system as claimed in claim 25, wherein said electrode means comprises a first pair of annular electrodes on the support member, and second annular electrodes on the stationary member, the annular electrodes of the first pair being arranged to face each other at an end of the annular orifice, and a second pair of annular electrodes on the support member, and second annular electrodes on the stationary member, the annular electrodes in the second pair being arranged to face each other at the other end of the annular orifice.