Patent ID: 6840223

Claim:
A driving device for an armature which is slidably provided within a housing filled with a fluid and which divides an inside of the housing into two fluid chambers, comprising a communicating hole enabling the fluid to pass between the two fluid chambers, wherein the communicating hole is formed such that the fluid passing through the communicating hole and out from the armature when the armature slides flows out at an angle to, and to the side of, a center axis of the armature, the driving device comprising: a controller that changes an amount of current supplied to an electromagnetic solenoid that generates an electromagnetic force to drive the armature, the controller changes the amount of current supplied to the electromagnetic solenoid at a first predetermined timing and imparts a force to the armature which is based on the outflow of the fluid, and which is able to rotate the armature in a direction of rotation around a center axis of the armature, wherein the armature is slidably provided within a housing filled with a fluid and which divides an inside of the housing into two fluid chambers, and the change in the amount of current supplied to the electromagnetic solenoid at the first predetermined timing is larger than a difference between an upper limit value and a lower limit value of a control range of the amount of current between the time when the armature starts to be driven and the time when the armature stops being driven.