| 摘要 |
PROBLEM TO BE SOLVED: To set an equal pressure path, for connecting a back space with a secondary side port with respect to a valve member, to be large in passage sectional area in a pressure balanced type motor-operated valve.SOLUTION: A cylindrical valve guide 2 is disposed in the valve chamber 1A of a valve body 1. A valve member 3 is disposed to be slidable in the valve guide 2. The valve member 3 is held by a connection rod 4 penetrating a cap member 5 and a male screw shaft 51. The connection rod 4 is connected to the magnet rotor 62 of a stepping motor 6. A female screw member 63 fixed to the magnet rotor 62 is screwed with the male screw shaft 51. A valve body 31 of the valve member 3 is formed into a cylindrical shape to be slidable in the guide surface 2a of the valve guide 2, and a needle part is eliminated. A tapered seating surface 21b is formed in a valve seat 21 defining a valve port 21a. An annular coupling part 22 defining a primary side port 11a is formed in the valve guide 21. The valve guide 2 is integrally fixed to the valve body 1 by the coupling part 22. An equal pressure path 1A2 is made to connnect a part around the valve guide 2 of the valve chamber 1A to a back space 1A1. |
