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:
Dec. 15, 1981
Filed:
Jul. 09, 1980
Ravi Tandon, Manchester, GB;
John G Schofield, Dodworth Barnsley, GB;
Dunlop Limited, London, GB;
Abstract
The invention relates to playballs, e.g. tennis balls, having a core pressurized with a low permeability gas, e.g. sulphur hexafluoride. Use of such gases can cause the ball to emit a pinging noise on bouncing. The invention provides a core (1) pressurized with gas of low permeability, the internal wall surface (3) of core (1) being profiled by a multiplicity of depressions or protuberances (4), the outer wall surface (2) of the core being smooth. The profiling is preferably in the form of dimples or pimples of circular plan view.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile