The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 16, 1978
Filed:
Jun. 04, 1976
Philip Thorbus Nichols, Salt Lake City, UT (US);
Paul Jene Watts, Salt Lake City, UT (US);
Becton, Dickinson and Company, East Rutherford, NJ (US);
Abstract
A pumping system for dispensing controlled and variable amounts of fluids in predetermined quantities includes a pump piston which moves axially in a pump chamber. The piston is reciprocated by a drive lead nut cooperating with a non-rotatable lead screw attached to the piston. The piston is sealed to the pump chamber by a seal element whose distance from the lead nut is fixed regardless of the position of the piston, thus protecting the seal. The rotatably driven lead nut includes a hollow driven shaft, containing lubricant, so that the lead screw is lubricated as it travels into the shaft of the lead nut. The motor for the system is a pulse operated reversible stepping motor enabling accurate output from the pump, for example, between .01 ml/min to 9.99 ml/min as controlled by the stepping motor. One motor may drive two pumps for a continuous controlled pumping system. If desired a flush mechanism may be used to rinse the piston of any pumped material which adheres to the surface.