JPS5979601U

JPS5979601U - Cavitation prevention circuit

Info

Publication number: JPS5979601U
Application number: JP17668682U
Authority: JP
Inventors: 田口　成二
Original assignee: ダイキン工業株式会社
Priority date: 1982-11-22
Filing date: 1982-11-22
Publication date: 1984-05-29
Also published as: JPH0210322Y2

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of drawings]

第１図はこの考案の一実施例の回路図、第２図は吐出量
制御弁の断面図、第３図は第２図Ａ−Ａ線矢視図である
。１・・・可変ポンプ、３・・・絞り切換弁、１３・・・
バイパス形圧力補償弁、２２・・・吐出量制御弁、２６
・・・バネ室、３θ・・・バネ、８２・・・ダンパ室、
８３・・・スプール、８４・・・遅延用ピストン、８５
・・・溝、９０・・・リターンスプリング、９５・・・
通路。FIG. 1 is a circuit diagram of an embodiment of this invention, FIG. 2 is a sectional view of a discharge amount control valve, and FIG. 3 is a view taken along the line A--A in FIG. 1... Variable pump, 3... Throttle switching valve, 13...
Bypass type pressure compensation valve, 22...Discharge amount control valve, 26
...Spring chamber, 3θ...Spring, 82...Damper chamber,
83... Spool, 84... Delay piston, 85
...Groove, 90...Return spring, 95...
aisle.

Claims

[Scope of utility model registration request]

In the pump line 2 of the variable displacement pump 1, a throttle switching valve having a pilot passage 8 that is closed in the switching position, opened in the neutral position, and communicates with the tank, and
A bypass type pressure compensating valve 13 is connected between the pump line 2 and the tank line to control the differential pressure before and after the throttle in the throttle switching valve to be constant, and a discharge amount control section of the variable displacement pump 1 The pump line 2 is connected to the pilot chamber 24 of the discharge amount control valve 22 which is connected to the pump line 2 and the tank 23 by switching the pump line 21 to the pump line 2 and the tank 23. The pump line 2 is connected, and the spring chamber 26 is connected to the pilot passage 8 of the throttle switching valve via a pilot line 29, so that the spring chamber 2 of the discharge amount control valve 22 is connected when the throttle switching valve is in the neutral state. 6 is connected to the tank via the pilot passage 8, a damper chamber 82 is provided adjacent to the spring chamber 2-6 of the discharge amount control valve 22.
A delay piston 84 is slidably fitted into the damper chamber 82, and a turn spring 90 is provided in the back pressure chamber 88 of the delay piston 84 to push the delay piston 84 toward the spring chamber 26 side. is biased so that the end surface of the delay piston 84 can come into contact with the end surface of the spool 83 of the discharge amount control valve 22, while the spring chamber is 26 and the back pressure chamber 88, and a groove 15 is provided in at least one of the end face of the spool 83 of the discharge amount control valve 22 or the end face of the delay piston 84, and the end face of the delay piston 84 is provided with a groove 15. , is in contact with the end face of the spool 83 of the discharge amount control valve 22, the groove 15 acts as a restriction for the passage 95.