Throttling structure for use in a fluid pressure device

摘要

The present invention relates to a throttling structure for use in a fluid pressure device. A nozzle passage is formed between a primary side port and a nozzle back pressure chamber. A throttling mechanism made up from a plurality of orifice plates is disposed in the nozzle passage. Small diameter opening holes, which are smaller in diameter than the nozzle passage, are provided in the orifice plates. Outer edge portions of the orifice plates are retained in a second body part via seal members. Further, the orifice plates are separated mutually from each other by a predetermined distance along the direction of extension of the nozzle passage.

主权项

1. A throttling structure for use in a fluid pressure device having a body, including a first body part, a second body part arranged on an upper portion of the first body part, and a third body part arranged on a further upper portion of the second body part, in which a port is formed in the first body part to which a pressure fluid is supplied, for carrying out a pressure control on the pressure fluid, comprising:
an introduction chamber configured to be provided between the second body part and the third body part into which the pressure fluid is introduced; a communication passage configured to provide communication between the introduction chamber and the port, the communication passage extending along an axial direction of the second and third body parts, bending in a radial direction within the third body part, and connecting to a communication hole in communication with the introduction chamber; and a throttling mechanism disposed in the communication passage and having a plurality of flow passages through which the pressure fluid flows, the flow passages being smaller in diameter than the communication passage, for reducing a flow amount of the pressure fluid, wherein the plurality of flow passages are disposed mutually adjacent to each other at predetermined intervals along a flow direction of the pressure fluid, and wherein the throttling mechanism includes a plurality of orifice plates with seal members provided on peripheral edges of the orifice plates such that at least one of the seal members is sandwiched between the orifice plates, each of the orifice plates includes an opening hole provided in a middle of the orifice plate and defining the flow passage, the opening holes being aligned with each other and parallel to the flow passage, a lowermost orifice plate being sandwiched, in the axial direction, between a lowermost seal member abutting the upper portion of the first body part and a lower portion of the second body part, and an uppermost orifice plate abutting an uppermost seal member abutting a lower portion of the third body part.