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Hand-held vacuum and pressure pump

  • US 4,954,054 A
  • Filed: 09/30/1988
  • Issued: 09/04/1990
  • Est. Priority Date: 09/08/1986
  • Status: Expired due to Term
First Claim
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1. A hand-held pump, comprising:

  • (a) cylinder means and having an inlet opening and an outlet opening,(b) biased piston means, for creating a pressure differential and for drawing air through the inlet opening of the cylinder means when said biased piston means is drawn back, and for automatically returning said piston means to the end of said cylinder means when said piston means is no longer drawn back,(c) inlet valve means coupled with the inlet opening of the cylinder means,and outlet valve means coupled with the outlet opening of the cylinder means,(d) hand operated piston retractor means for drawing said piston means back within said cylinder means, whereby drawing said piston means back causes air to be drawn into said cylinder means via the inlet opening of the cylinder means, and whereby releasing said piston retractor means causes air which was drawn in to be forced out via the outlet opening of said cylinder means, and(e) valving means between the inlet valve means and the outlet valve means, and having a port to the valving means, the valving means being movable between a first position wherein the differential pressure creates a pressure at the port and the pump acts as a pressure pump, and a second position wherein a vacuum is created at the port and the pump acts as a vacuum pump.

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