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:
Sep. 27, 1988
Filed:
May. 11, 1987
Niels D Jensen, Bjerringbro, DK;
Bjarne Dissing, Hammel, DK;
Grundfos International A/S, , DK;
Abstract
A pump with a canned motor (1) comprises a hollow shaft (4) open at the ends (5, 6) and provided with shaft ends (7, 8) and made of a relatively thin-walled tube. The portions (7, 8) of the shaft (4) are of a reduced diameter (d.sub.1, d.sub.2). A reciprocating ball (12) is situated in the cavity between a first shaft portion (8) and a second shaft portion (7), said first shaft portion forming a shaft end and provided with a spline (17). This ball abuts seats (13, 14) resulting from the reduction of the diameter of the shaft portions (7, 8), whereby the ball (12) and the seats (13, 14) form a valve. In this manner the valve of the hollow shaft (4) is provided in a particularly simple manner as the seats (13, 14) can be provided simultaneously with the manufacture of the shaft portions (7, 8) of a reduced diameter. The shaft portion (8) carrying the impeller (10) is provided with a spline which provides the hollow shaft (4) with the necessary torsional strength.