Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB524352A
Inventor
Frank Bryan Lenz
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hawley Products Co
Original Assignee
Hawley Products Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hawley Products CofiledCriticalHawley Products Co
Priority to GB524352ApriorityCriticalpatent/GB706656A/en
Publication of GB706656ApublicationCriticalpatent/GB706656A/en
D21J—FIBREBOARD; MANUFACTURE OF ARTICLES FROM CELLULOSIC FIBROUS SUSPENSIONS OR FROM PAPIER-MACHE
D21J3/00—Manufacture of articles by pressing wet fibre pulp, or papier-mâché, between moulds
Abstract
706,656. Diaphragms. HAWLEY PRODUCTS CO. Feb. 28, 1952, No. 5243/52. Class 40 (4) [Also in Group V] The natural resonance of air acoustic diaphragm is lowered by providing it with a plurality of corrugations 15 at its periphery. The corrugations are formed by re-pressing a diaphragm with a single peripheral corrugation. U.S.A. Specification 1,872,583 is referred to.
GB524352A1952-02-281952-02-28Method of making an acoustic diaphragm
ExpiredGB706656A
(en)