BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a left side elevation of a first embodiment of a mirror handle illustrating the principles of the present invention;
FIG. 2 is a perspective view of a complete mirror assembly utilizing a second embodiment of a mirror handle constructed according to the principles of the present invention;
FIG. 3 is a bottom plan view of the handle illustrated in FIG. 1;
FIG. 4 is a rear elevation of the mirror handle depicted in FIG. 1;
FIG. 5 is a perspective view illustrating the fabrication of a complete mirror assembly; and
FIG. 6 is an exploded perspective view of the mirror assembly illustrated in FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is designed and intended for use by a dentist or other health professional to facilitate an examination of the mouth, teeth and gums of a patient. Referring to FIGS. 1 and 3, a handle 1 is depicted which may be gripped and manipulated by the user. The handle 1 includes a ribbed or knurled region 2 which assists the user, typically a dentist, in maintaining a grip on the handle during the examination or treatment of a patient. The handle I is formed of a suitable thermoplastic material such as polycarbonate or preferably a general purpose polypropylene containing approximately twenty percent glass. The basic criteria for the thermoplastic material are that it must be autoclavable and maintain the shape of handle 1 without being excessively brittle or flexible. The handle 1 must not be easily broken and of course cannot be so expensive as to be prohibitive to the end user.
In one preferred embodiment of the present invention, the handle has a substantially hexagonal cross section with substantially flat sides 3, 4 and 5, for example. Each side 3, 4, 5 is joined to an adjacent side via a radius 6 and a relative short flattened section 7. Referring also to FIGS. 4 and 5, a longitudinal groove 8 extends for substantially the entire length 9 of the handle 1. The handle 1 includes a rounded base 11 terminating at button 13, and an opposite, substantially flat forward tip region 12.
Referring also to FIG. 2, a complete mirror assembly 14 utilizing a second embodiment of the handle 15 is depicted. The handle 15 includes a tapered, ribbed portion 16 intended for contacting the index finger of the user. A rear ribbed portion 17 is formed on the handle surface to contact the hand of the user in an area between the fingers and the wrist. The ribbed portions 16 and 17 are preferably formed of a flexible thermoplastic material having a durometer of approximately thirty five. The mirror assembly 14 includes a mirror 18 having a multilayered Rhodium coating.
Referring also to FIG. 6, the mirror 18 is seen to be substantially circular in shape and has a thickness 22. The mirror 18 is formed to include a perpendicular sidewall 34 and a beveled sidewall 35. The beveled sidewall 35 interconnects the perpendicular sidewall 34 and the reflecting surface 22 of the mirror 18. The mirror 18 resides within a thermoplastic carrier 19. A series of upper mirror clips 20 are formed on the periphery 21 of the carrier 19. The mirror clips 20 retain the mirror 18 and have a distal portion including an upper surface 32 that extends just below the plane defined by the reflecting surface 22 of the mirror 18. The carrier 19 also includes a series of handle head clips 24 which are formed on the periphery 21. The handle head clips 24 are formed to engage a handle head 23 which is affixed to the handle 15.
Referring also to FIG. 5, the method of fabricating the mirror assembly 14 can be understood. Initially, the mirror carrier 19 is premolded to assume a shape adapted to retain the mirror 18. The mirror 18 is then placed within the carrier 19 to create a subassembly. The surface 22 of mirror 18 may optionally be covered with a protective tape or cover 26 that is later removed when the mirror assembly 14 is completed. The combination of mirror 18 and carrier 19 is placed within the handle head 23. The handle head 23 which contains both the carrier 19 as well as the mirror 18 is placed within the mold half 25. At this point in the assembly process the handle head 23 has typically not yet been affixed to the mirror handle 2 or 15, as is the case for the carrier 19 residing in mold position 27. The end 12 of the mirror handle 2 or 15 is placed within the depression 33 in each mold position 27 and 31. A second, mating mold half (not shown) is placed over the mold half 25 to create a complete moldset which is held in place by threaded fasteners placed in threaded bores 28, 30 and 29. Once the mold halves are secured, a molten thermoplastic resin is injected into each mold position 27 and 31. The moldset is formed so as to allow the molten thermoplastic resin to reach the distal or upper portion 32 of each retaining clip, that is, the resin rises to a level that covers the flat upper surface 32 of each clip 20. After covering the level of surface 32, the beveled surface 35 of the mirror 18 is covered by the resin while the mirror surface 22 remains slightly above (on the order of 0.001 inch) the level of the resin. The carrier 19 holds the mirror 18 in place during the molding process and the cured resin ultimately holds the mirror 18 in place by forming a lip 49 which overlies the beveled surface 35. The carrier 19 and the handle 15 are fully bonded to the head 23 once the resin cures.
As seen in FIG. 6, the handle assembly 14 can also be formed by a similar over molding process. The handle 15 includes a core 36 formed of a first plastic material during a premolding process. In the example illustrated, the core includes a widened cylindrical region 37 into which voids 38,39, 40 and 41 are formed which can signify a company logo or brand name. The handle body 42 is formed by surrounding the core 36 with a mold (not shown) that extends between shoulders 43 and 44 and which substantially surrounds and isolates the core region 36. A second thermoplastic material is injected into the mold, forming the ribbed regions 16 and 17 as well as filling the voids 37 through 41, thereby creating the letters or symbols 45, 46, 47 and 48 that are defined by the voids.
Although the present invention has been described with reference to the foregoing examples, changes can be made to these specific embodiments without departing from the principles of the invention. For example, while the mirror assembly 14 is shown as a composite of two discrete molding processes, more molding steps can be introduced to create a more complex mirror assembly. Similarly, different materials may be used in forming the mirror assembly 14 depending on cost, strength, durability and aesthetic requirements. Thus, many other mirror configurations are possible, and the scope of the present invention may be appreciated only by reference to the claims.
Patent Application
20070287123
