| 摘要 |
PURPOSE:To facilitate to connect a vacuum gauge to the pump by a method wherein the internal part of a guide cylinder for a non-return valve at the side of suction is sealed by a bellows and the connecting part of the gauge is provided on the outside of a lid for the non-return valve. CONSTITUTION:The non-return valve 11 is provided with a rod-like guide member 12 on the back side thereof while the member is provided with a penetrating hole 13, penetrating therethrough into the axial direction at the center thereof and one end thereof is communicated with the end surface of the valve seat side thereof. The guide member 12 of the non-return valve 11 is inserted into the guide cylinder 15 projected into the inner side of the non-return valve lid 14 provided at one part of a pump casing 6 while the inside of the guide cylinder 15 is sealed by the bellows 16. The connecting part 17 of the gauge, communicated with the guide cylinder 15, is provided at the outside of the non-return valve lid 14, therefore, the connection of the vacuum gauge to the pump may be facilitated. |
