| 摘要 |
Disclosed is a flow path switching valve for a high pressure fluid spray nozzle is disclosed that can be operated remotely simply by turning flow on and off. In one embodiment a mid portion of the valve body has at least one passage therein leading from a central axial bore to first and second external ports. A poppet member received in the central axial bore directs fluid flow in a first position to the first external ports. The poppet member, when in a second position, closes the central axial bore through the outlet end of the valve body and permits fluid flow through the second set of external ports. A biasing member is located between the valve body and the poppet member biasing the poppet member toward the inlet end of the valve body. A guide in the valve body engages a corresponding feature on the rear end portion of the poppet member to align the radial arm on the spool portion with the at least one passage in the mid portion of the valve body at a first position of the poppet member and open the central axial bore through the outlet end of the valve body. When fluid flow is introduced into the inlet end of the valve body, the radial arm in the spool portion is misaligned away from the at least one passage in the mid portion of the valve body when fluid flow is reduced below a predetermined flow rate threshold, and the at least one radial arm of the spool portion is aligned at a second position different from the first position, closing the central axial bore through the outlet end when fluid flow is next introduced in the inlet end of the valve body above the flow rate threshold. Selection of the different flow paths is made by simply reducing flow through the valve below a predetermined fluid flow threshold and then increasing the flow rate above the threshold. |
