Mirror case

• US 3,918,799 A
• Filed: 05/01/1973
• Issued: 11/11/1975
• Est. Priority Date: 05/01/1973
• Status: Expired due to Term

• Current Assignee: Donnelly Corporation (Magna International Incorporated)
• Original Assignee: Arthur W. Kurz Jr, Harold R. Wilson
• Inventors: Kurz, Arthur W. Jr., Wilson, Harold R.
• Primary Examiner(s): Smith, Alfred E.
• Assistant Examiner(s): Tokar, Michael J.
• Application Number:
  US05/356,074
• Time in Patent Office: 924 Days
• Field of Search: 350/288,303,304,307,310
• US Class Current: 359/871
• CPC Class Codes: B60R 1/04 mounted inside vehicle B60R1/025, B60R1/08 take precedence

Abstract

A lightweight rearview mirror assembly for vehicles and a method for forming the same. The assembly includes a case formed from a thermoplastic material and a mirror element mounted therein. A thin, upstanding edge of the case is heated and curled into an arcuate, peripheral, retaining edge extending over the entire length of the mirror edge. The curled, arcuate edge defines therewithin a space extending between the entire thickness of the peripheral edges of the mirror and the case which allows the mirror and case to expand or contract in extreme temperatures without expelling or breaking the mirror element. Means are provided for preventing the mirror from vibrating within the case.

Claims

1. A rearview mirror assembly comprising a case and a mirror element having front and back surfaces and a peripheral edge fitted therein;

said case being molded in one piece from a thermoplastic material and having a back and a continuous peripheral side outlining said peripheral edge of said mirror element and being spaced outwardly therefrom;

said case including support means for supporting said mirror element;

said peripheral sides of said case including arcuate wall means curving over at least a portion of said peripheral edge and contacting said front surface of said mirror element for holding said mirror element against said support means, retaining said mirror element in said case, and preventing forward and rearward movement of said mirror element out of its general plane within said case;

said assembly including a space between the entire thickness of said peripheral edge of said mirror element and said outwardly spaced peripheral sides of said case;

said arcuate wall means including means for allowing differential expansion between said mirror element and said case generally in the plane of said element into said space while said arcuate wall means remain in contact with said front of said element;

said space adapted to be substantially filled by said peripheral edge of said mirror in different temperatures and providing an expansion and contraction area for said assembly to prevent breakage of said element when said assembly is exposed to extreme temperature conditions.

2. The assembly of claim 1 wherein said mirror element has a width and a length;

said support means for supporting said mirror element including shift preventing means for preventing a lateral shift in position of said mirror element in said case.

3. The assembly of claim 2 wherein said support means comprise at least one upstanding rib extending between the interior of said back of said case and said mirror element;

said shift preventing means comprising said rib and a thickness of impressionable material adhered to the back of said mirror element;

said rib extending into said impressionable material to prevent said mirror element from laterally shifting in said case;

said impressionable material also being glass retaining to prevent the scattering of pieces of said mirror element should it be accidentally broken.

4. The assembly of claim 3 wherein said upstanding rib includes a fin tapered toward said mirror element;

said fin being sufficiently resilient to bias said mirror element against said arcuate means for securing said element against said rib to prevent vibration of said elemeNt in said case.

5. The assembly of claim 1 wherein said support means for supporting said mirror element comprise at least one upstanding rib extending between the interior of the back of said case and the back of said mirror element.

6. The assembly of claim 5 including a ledge extending partially into the thickness of said peripheral sides of said case for at least partially supporting the periphery of said mirror.

7. The assembly of claim 1 wherein support means for said mirror element include a ledge extending into the thickness of said peripheral side from the interior surface thereof for at least partially supporting said mirror.

8. The assembly of claim 1 wherein said arcuate wall means for securing said mirror element against said supporting means include a thin, semicircular flange integral with said peripheral side of said case, said means for allowing differential expansion including an end surface on said flange;

said flange being thinner than the remainder of said peripheral side and extending over said peripheral edge of said mirror element along the entire periphery thereof to retain said element in said case;

said flange including an internal space communicating with said space between said peripheral edge of said mirror element and said peripheral side of said case;

said mirror element including a generally planar front surface;

said end surface contacting said front surface generally normally thereto whereby said mirror element can expand in a direction parallel to the plane of said front surface beneath said end surface.

9. The assembly of claim 1 wherein said arcuate wall means extend over the entirety of said peripheral edge of said mirror element and contact said front surface of said element a distance spaced inwardly from said peripheral edge sufficient to hide most chips or other production irregularities present in said peripheral edge.

10. A rearview mirror assembly comprising a case and a mirror element supported in said case and having a peripheral edge;

said case having support means for supporting said mirror element in said case and a continuous peripheral case including outlining said peripheral edge;

said caseincluding a thin flange integral with said peripheral side and extending along the entire length thereof;

said flange being thinner than the remainder of said peripheral side and extending over said peripheral edge and into contact with the front of said mirror element about the entire periphery of said mirror element whereby said mirror is retained against said spacing means;

said flange providing a space interior thereof between said peripheral side and the entirety of said peripheral edge of said mirror element and including means for allowing differential expansion between said mirror element and said case generally in the plane of said element into said space while said flange remains in contact with said front of said element whereby said mirror element can expand and said case can contract in extreme temperatures without breaking said mirror or causing said mirror to separate from said case.

11. The mirror of claim 10 wherein said flange is arcuate and includes a dome-shaped space therewithin.

12. The mirror of claim 11 wherein said arcuate flange is semicircular in cross-section.

13. The assembly of claim 10 wherein said flange includes two parallel sides, said means for allowing differential expansion including an end surface of said flange which is substantially perpendicular to said parallel sides;

said mirror element including a generally planar front surface;

said end surface contacting said front surface generally normally thereto whereby said mirror element is prevented from vibrating in said case but allowed to expand and contract beneath said end surface.

14. The assembly of claim 10 wherein said spacing means comprise a ledge extending into the thickness of said peripheral side such that said ledge has a predetermined width for supporting the peripheral edge of said mirror;

said flAnge extending over said peripheral edge of said mirror a distance greater than the width of said ledge to prevent said element from being expelled from said case and to hide any irregularities in the peripheral edge of said mirror element.

15. The assembly of claim 10 wherein said case includes a prismatic mirror element having non-parallel front and back reflecting surfaces and means for shifting said case and prismatic mirror with respect to an external support for said assembly;

said shifting means allowing the selection of day and night positions of said case and prismatic mirror element.

16. The assembly of claim 10 wherein said case includes a back and at least one integral upstanding rib comprising said support means;

said rib extending between the back of said mirror element and the back of said case;

said flange retaining said mirror element against said rib to prevent vibration of said element in said case.

17. The assembly of claim 16 wherein an impressionable layer of material is adhered to the back of said mirror element;

said rib extending into said layer to prevent vibration of said mirror within said case and to prevent pieces of said mirror from scattering should said mirror be accidentally broken.

18. A case molded in one-piece from one thermoplastic material and adapted to receive a mirror element having a generally planar front surface;

said case including support means for supporting such a mirror element and a continuous upstanding peripheral side extending therearound and adapted to outline the periphery of a mirror element when fitted within said case;

said upstanding peripheral side including a portion adjacent to and extending along and above the entirety of the peripheral edge of such a mirror element when said mirror element is received therein, said portion being thinner than the remainder of said side to provide a space between said portion and the thickness of the peripheral edge of such a mirror element;

said thinner portion having a uniform height at all points around said periphery of said case sufficient to allow said portion to be curled in semicircular configuration over the edge of a mirror element when received in said case such that the end of said thinner portion is adapted to contact said planar front surface of said mirror normally thereto.

19. The case of claim 18 wherein an intermediate portion of said peripheral side adjacent the entirety of the thickness of a mirror element adapted to be received within said case has a thickness greater than said thinner portion but less than the thickness of the remainder of said side;

said thinner portion extending from and beyond said intermediate portion.

20. The case of claim 18 wherein said case includes a back and said support means comprise at least one upstanding rib extending from said back adapted to support such a mirror element.

21. The case of claim 20 wherein a portion of said upstanding rib is tapered.