Fluid actuated clutch assembly

Claim 1

A fluid actuated clutch assembly comprising: a. a rotary structure of substantially annular shape rigidly secured to a shaft for rotation therewith, said rotary structure having a radially extneding flange part and a boss part, said boss part being provided with radially outer and inner annular recesses formed on one end face thereof, b. a stationary structure of substantially annular shape supported by a pillow block, axially facing said rotary structure, and located independently of said rotary structure to leave an axial space therebetween for allowing relative rotation of said rotary structure, said stationary structure being provided with radially outer and inner annular grooves formed on an end face thereof, opposite to said one end face of said rotary structure and opening in longitudinal direction thereof, c. an inflatable friction member fixedly attached said flange part of said rotary structure, d. a relative annular sealing ring fixedly inserted into said radially outer annular recess of said rotary structure, said sealing ring being provided with a plurality of axial fluid passages, e. a plurality of communication passages formed in said rotary structure, each one having one end open into a respective fluid passage of said sealing ring and the other end being fluid connected to said inflatable friction member, f. a plurality of one-way valve devices, each provided in a respective communication passage and having a valve member slidably provided therein and biased into its first, closed position for preventing counterflow of a working fluid under pressure in the respective communication passages from said inflatable friction member during the clutch operation of said inflatable friction member, by means of a spring, g. a plurality of actuating piston devices, each having a cylinder and a piston and mounted within said radially inner annular recess of said rotary structure, substantially in alignment with the respective one-way valve devices, said piston being slidable within said cylinder in an axial direction and biased Away from said one-way valve device by said valve member with its outer end protruding into said space, h. a substantially annular sealing piston slidably and hermetically carried within said radially outer annular groove of said stationary structure in a manner to form a substantially annular fluid chamber, which communicates with a fluid source, between the inner end face thereof and the inner wall of said groove, said sealing piston having a plurality of axial fluid passages and having an annular sealingly, sliding element mounted within its outer end face thereof, said sliding element being provided with a plurality of axial fluid passages, each being substantially in alignment with the respective fluid passage of said sealing piston, said sliding element being provided with an annular fluid accumulative groove, which communicates circumferentially with all of said holes of said sliding element, at the outer side end face thereof, i. a substantially annular discharging piston slidably and hermetically carried by said radially inner annular groove of said stationary structure in a manner to form a substantially annular fluid chamber communicating with the fluid source, between the inner end face thereof and the inner wall of said groove, and j. means for selectively supplying the working fluid to said sealing and discharging pistons in accordance with a predetermined sequence; wherein said sealing piston is biased away from the inner side wall of said radially outer groove, upon application of a fluid pressure thereto for bringing said sliding element thereof into sealing contact with said sealing ring so that the working fluid is supplied to said inflatable friction member, and wherein said discharging piston is biased away from the inner side wall of said radially inner annular groove, upon application of a fluid pressure thereto, for bringing the outer end face thereof into abutting engagement with said protruding end of said actuating piston, consequently moving said piston and said valve member into its second, open position so that said communication passage is opened.