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:
Jul. 11, 1978
Filed:
Apr. 21, 1976
Horace Stanley Hawthorne, West Midlands, GB;
Lucas Electrical Limited, Birmingham, GB;
Abstract
An arch form comprises a tooth portion including a plurality of integral teeth injection moulded in pastics material and arranged in a curved row, and a gum portion in situ injection moulded onto the tooth portion so as to overlie an upper surface thereof. An undulating ridge extends along the upper surface of the tooth portion and is surrounded by the gum portion. Front teeth of the tooth portion have a substantially natural inclination with respect to the general plane of the tooth portion, whereas rear teeth thereof are inclined towards the front teeth such that their direction of extent is angled at 10.degree. to 20.degree. with respect to their counterparts in a natural set of teeth. A method of moulding the arch form requires the provision of a two-part mould defining the shape of the tooth portion, and a further mould part defining the shape of the gum portion. One part of the two-part mould includes a curved row of interconnected cavities defining the shapes of the individual teeth of the tooth portion: the other part thereof defines the upper surface of the tooth portion and the undulating ridge. Substantially white plastics material is injected into the two-part mould so as to form the tooth portion. The said other part of the two-part mould is then removed and is replaced by the further mould part. Red or pink plastics material is then injection into further mould part so as to mould the gum portion in situ on the tooth portion. The further mould part is withdrawn, and the completed arch form is removed. The arch form can be produced in an economic manner and in a form which facilitates mass production.