(19)
(11) EP 1 818 538 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
06.08.2008 Bulletin 2008/32

(43) Date of publication A2:
15.08.2007 Bulletin 2007/33

(21) Application number: 07250389.9

(22) Date of filing: 30.01.2007
(51) International Patent Classification (IPC): 
F04B 17/04(2006.01)
F04B 53/14(2006.01)
 F04B 53/02(2006.01)
(84) Designated Contracting States:
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR
Designated Extension States:
AL BA HR MK RS

(30) Priority: 10.02.2006 US 350860

(71) Applicant: Defond Components Limited
Hong Kong SAR (CN)

(72) Inventors:
  • Chan, Kai Chi
    Chaiwan Hong Kong SAR (CN)
  • Ho, Man Ting
    Chaiwan Hong Kong Sar (CN)

(74) Representative: Martin, David John et al
Marks & Clerk 43 Park Place
Leeds LS1 2RY
Leeds LS1 2RY (GB)

   


(54) Fluid pump


(57) A fluid pump (10) comprises a chamber (230) and a plunger (410) extending into the chamber (230) and supported for sliding movement on a suction stroke to introduce fluid into the chamber (230) and on a discharge stroke to force fluid out of the chamber (230). A driver (300) slides the plunger (410) in opposite directions. A seal ring (700) is provided between the chamber (230) and the plunger (410) and yet permits the plunger's sliding movement. The seal ring (700) has an outer annular portion (710) of a generally flat cross-section (711) clamped fast in a wall of the chamber (230) and an inner annular portion (720) of a bulbous cross-section (721) in sliding sealing engagement with the plunger (410).







Search report