Pressure-regulating and cut-off valve arrangement
Реферат: 1333117 Valves DANFOSS AS 16 Dec 1970 [16 Dec 1969] 59751/70 Heading F2V A pressure-regulating and cut-off valve arrangement for controlling the flow of fuel oil from a pump to a burner comprises, an inlet 3, Fig. 1, passages 5 and 7 leading to a reservoir, an outlet 9 leading to the burner, a setting piston 12 permanently acted upon by a spring 17, a further spring 18 which acts upon the displaced piston to increase the gradient of the loading characteristic, and a regulating piston comprising a first member 14 and a second member 15 which seats against an "0"-ring 11 to close the outlet to the burner. A restriction 36 leads to a chamber 34 which is closed by a plate 19 and "0"-ring 35. The position of the spring 18 relative to the setting piston 12 is adjustable by means of a screw 20 and a nut 24. When the pump is started up, oil entering the chamber 16 displaces the setting piston 12 to the right and into contact with the spring 18, whilst the regulating piston remains stationary. With increasing pressure, the setting piston is displaced further to the right until eventually (see Fig. 2) oil begins to flow through the groove 31, the port 27, the passage 28 and the port 29 into the chamber 30. The pressure in this chamber displaces both the members 14 and 15 of the regulating piston simultaneously to the right to open the outlet 9 and also to uncover the passage 5 so as to maintain a constant pressure at the outlet. Meanwhile oil seeps into the chamber 34 through the restriction 36. When the pump is switched off, the setting piston 12 is returned by the action of springs 17 and 18. This movement is transmitted to the member 15 of the regulating piston through the agency of the oil trapped in the chamber 34, and the member is rapidly displaced relative to the other member 14 so as to shut off the outlet 9. The increased pressure in the chamber 30, caused by the return of the member 15, is relieved by further displacement of the member 14 to the right. The arrangement is eventually returned to its initial position by the action of the spring 17 only. The upper and lower parts of the Figures illustrate manufacturing tolerances.
Pressure-regulating and cut-off valve for fuel-oil pumps
Номер патента: US3687154A. Автор: Jorgen Hartvig Petersen,Ingvard Mosby Madsen. Владелец: Danfoss AS. Дата публикации: 1972-08-29.