Claims
- 1. A navigational, charting, or calculating device comprising:
- base plate means,
- disc means comprising a transparent circular member having an upper surface adapted to be marked upon, and a circular base having a recess therein adapted to receive a map and said transparent circular member for holding and securing a map between said transparent circular member and said circular base.
- said base plate means having a circular cavity in its top side for removably receiving said disc means for rotation therein,
- said base plate means having a reference mark formed on said top side,
- said transparent circular member having its peripheral edge divided into increments of interest for alignment with said reference mark upon rotation of said disc means,
- sliding means having a straight edge marking guide, and means on said base plate means for supporting said sliding means above said disc means for sliding movement across said disc means in a direction perpendicular to the length of said straight edge.
- 2. The device of claim 1 wherein:
- said sliding means comprises:
- a first member having two parallel straight edges,
- a second member supported by said first member to slide along said parallel straight edges of said first member and having a straight edge parallel to said two parallel straight edges with equally spaced marks along its length representative of distance,
- said base plate means has two spaced parallel guide means located on opposite sides of said disc means for supporting said first member for sliding movement across said disc means in a direction perpendicular to its parallel straight edges.
- 3. The device of claim 2 comprising:
- stop means formed on said base plate means for preventing said sliding means from sliding off of said base plate means.
- 4. The device of claim 1 comprising:
- two spaced parallel slots means facing each other and formed on the top side of said base plate means and on opposite sides of said circular cavity for receiving opposite ends of said sliding means for supporting said sliding means for movement across the top of said disc means and for allowing said sliding means to hold said disc means in said circular cavity,
- stop means formed on said base plate means for preventing said sliding means from sliding off of said base plate means,
- said sliding means comprising a flexible member adapted to be flexed for allowing said sliding means to be removed from and inserted into said parallel slot means.
- 5. The device of claim 1 comprising:
- a travel direction mark on the back side of said base plate means in alignment with said reference mark,
- degree marks representative of magnetic declination from true north formed on the back side of said base plate means on opposite sides of said travel direction mark,
- a magnetic compass comprising:
- a base having a first end and a second end,
- a reference point formed on said base,
- a magnetic needle rotatably supported by said base, and
- a transparent plate with degree marks rotatably secured to the second end of said base, and
- means for adjustably securing said base of said magnetic compass to the back side of said base plate means to allow said reference point of said base to be located opposite one of said degree marks representative of magnetic declination in the area in which said device is to be used.
- 6. A navigational, charting, or calculating device comprising:
- base plate means,
- disc means comprising a transparent circular member having an upper surface adapted to be marked upon and a circular base adapted to support said transparent circular member for holding and securing a map between said transparent circular member and said circular base,
- said circular base of said disc means having an extending flange around its edge forming a circular cavity for removably receiving a circular map or the like and said transparent circular member,
- said base plate means having a circular cavity in its top side for removably receiving said disc means for rotation therein,
- said base plate means having a reference mark formed on said top side,
- said disc means having its peripheral edge divided into increments of interest for alignment with said reference mark upon rotation of said disc means,
- sliding means having a straight edge marking guide, and means on said base plate means for supporting said sliding means above said disc means for sliding movement across said disc means in a direction perpendicular to the length of said straight edge.
- 7. The device of claim 6 comprising:
- a notch formed in the periphery of said transparent circular member of said disc means, and
- an inward projection formed on the inside surface of said flange adapted to fit into said notch and into a similar notch formed in the periphery of a circular map or the like for holding said transparent circular member, a map or the like, and said circular base, fixed with respect to each other when said transparent circular member, and said flat circular base are assembled together with a map or the like located there between.
- 8. A navigational, charting, or calculating device comprising:
- base plate means,
- disc means comprising a transparent circular member having an upper surface adapted to be marked upon and a circular base adapted to support said transparent circular member for holding and securing a map between said transparent circular member and said circular base,
- said circular base of said disc means having an extending flange around its edge forming a circular cavity for removably receiving a circular map or the like and said transparent circular member,
- said base plate means having a circular cavity in its top side for removably receiving said disc means for rotation therein,
- said base plate means having a reference mark formed on said top side,
- said disc means having its peripheral edge divided into increments of interest for alignment with said reference mark upon rotation of said disc means,
- sliding means having a straight edge marking guide supported above said disc means for sliding movement across said disc means in a direction perpendicular to the length of said straight edge,
- two spaced parallel slots means facing each other and formed on the top side of said base plate means and on opposite sides of said circular cavity for receiving opposite ends of said sliding means for supporting said sliding means for movement across the top of said disc means and for allowing said sliding means to hold said disc means in said circular cavity, and
- stop means formed on said base plate means for preventing said sliding means from sliding off of said base plate means,
- said sliding means comprising a flexible member adapted to be flexed for allowing said sliding means to be removed from and inserted into said parallel slot means.
- 9. The device of claim 8 comprising:
- a notch formed in the periphery of said transparent circular member of said disc means, and
- an inward projection formed on the inside surface of said flange adapted to fit into said notch and into a similar notch formed in the periphery of a circular map or the like for holding said transparent circular member, a map or the like, and said circular base, fixed with respect to each other when said transparent circular member, and said flat circular base are assembled together with a map or the like located therebetween.
- 10. The device of claim 8 comprising:
- a travel direction mark on the back side of said base plate means in alignment with said reference mark,
- degree marks representative of magnetic declination from true north formed on the back side of said base plate means on opposite sides of said travel direction mark,
- a magnetic compass comprising:
- a base having a first end and a second end,
- a reference point formed on said base,
- a magnetic needle rotatably supported by said base, and
- a transparent plate with degree marks rotatably secured to the second end of said base, and
- means for adjustably securing said base of said magnetic compass to the back side of said base plate means to allow said reference point of said base to be located opposite one of said degree marks representative of magnetic declination in the area in which said device is to be used.
Parent Case Info
This application is a continuation-in-part of U.S. Patent application Ser. No. 454,451, filed Mar. 25, 1974 now abandoned.
US Referenced Citations (12)
Foreign Referenced Citations (4)
Number |
Date |
Country |
1,047,729 |
Dec 1953 |
FR |
123,886 |
Jan 1949 |
SW |
93,227 |
Nov 1938 |
SW |
474,269 |
Oct 1937 |
UK |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
454451 |
Mar 1974 |
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