| 摘要 |
A weighing valve device comprises a housing (101) with a cover (104) , an axially movable piston (102) in a bore in the housing (101) and an enclosed body (103) of plastically deformable material in the piston (102). A differential piston (105-107) with a smaller diameter piston part (106) is in contact with the body (103) and with a larger diameter piston part in the form of a diaphragm (105) clamped between the housing (101) and the cover (104) and backed by a disc (107). A valve with an axially movable, spring-biassed valve member (110) is in contact with the diaphragm. A compressed air pressure acting on the diaphragm (105) and governed by the valve is adapted to counteract a mechanical force on the piston (102). The smaller diameter part (106) of the differential piston (105-107) rests against the disc (107) at its center. The diaphragm (105) and the disc (107) are provided at their centres with a through passage (111) for venting of compressed-air. The valve member (110) is arranged over the through passage (111). The smaller diameter piston part (106) is guided by a guide sleeve (108') in a guide block (108) above the enclosed body (103). |
