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. 06, 1994
Filed:
Oct. 05, 1992
Nordson Corporation, Westlake, OH (US);
Abstract
A tribo-electric powder spray gun includes a diffuser for mixing powder with a conveying gas, a charging portion downstream of the diffuser, and a sprayhead at the outlet of the charging portion for dispensing the charged powder. The charging portion has an inner core removably positioned within a hollow outer cylinder with an annular gap formed between the outer cylinder and inner core providing a charging flowpath for the powder. The inner core and the outer cylinder have undulating or wavy charging surfaces made of an electrically insulating material, so that the annular gap provides a tortuous path for the powder, enhancing powder contact and the charge imparted to the powder. Grounding is provided by surface conduction of the electrically insulating contact material through a ground ring located outside the powder path at the inlet to the charging portion of gun where the greatest amount of charging occurs. By locating the ground ring outside the powder path, the ground ring is kept clean and the amount of charging surface is maximized. The inner core and the outer cylinder are longitudinally symmetrical to facilitate re-assembly.