Gearbox drive for a speedometer

A gearbox for obtaining the proper drive ratio between an element in the drive train of a vehicle and a speedometer or odometer, comprising;

• housing means, an input gear mounted for rotation in the housing means, an output gear mounted for rotation in the housing means, and intermediate gear means engaging the input gear and the output gear to rotate the output gear in the same direction and at a predetermined drive ratio with respect to the input gear, said input gear and output gear being positioned with respect to the input gear, said input gear and output gear being positioned with respect to each other to react in generally opposite directions on the intermediate gear means upon rotation of the input gear in one direction, said housing means being constructed to permit a reversal of the relative positions of the input and output gears upon rotation of the input gear in the other direction so that the input gear and the output gear react in generally opposite directions against the intermediate gear means in either direction of rotation of the input gear, the housing means including a first gear case rotatably supporting the input gear and a second gear case rotatably supporting the output gear, said intermediate gear means being supported in at least one of the first and second gear cases, said first and second gear cases being connectable in a first position with the axis of the input gear spaced from the axis of the output gear, and being connectable in a second position rotated from the first position to change the relative position of the input gear and the output gear with respect to the intermediate gear means, the first gear case having first bearing means therein to support the input gear and second and third bearing means therein for supporting either the intermediate gear means or the output gear, said first, second and third bearings means in the first gear case being located on axes defining an equilateral triangle, said second gear case having a first bearing means therein for supporting the output gear, and a second and third bearing means therein for supporting either the intermediate gear means or the input gear, said first, second and third bearing means in the second gear case being located on axes defining an equilateral triangle equal to the first gear case equilateral triangle and being coincident therewith, said equilateral triangles having apexes lying in a common circle having a center, and fastening elements on the first gear case and the second gear case member spaced 120 degrees apart with respect to the center so that the first gear case member may be positioned in either of said first and second positions.

A gearbox for obtaining the proper drive ratio between an element in the drive train of a vehicle and a speedometer or odometer, comprising;

• housing means, an input gear mounted for rotation in the housing means, an output gear mounted for rotation in the housing means, intermediate gear means engaging the input gear and the output gear to rotate the output gear in the same direction and at a predetermined drive ratio with respect to the input gear, said input gear, said output gear and said intermediate gear means being rotatable on axes defining an equilateral triangle so that upon rotation of the input shaft in one direction the radial forces imposed on the intermediate gear means by the input gear will be generally equal and opposite the forces imposed on the intermediate gear means by the output gear, including a first gear case member supporting the input gear, a second gear case member supporting the output gear, said first gear case member having first bearing means therein to support the input gear, and second and third bearing means therein for supporting either the intermediate gear means or the output gear, said first, second and third bearing means in the first gear case member being located on axes defining an equilateral triangle, said second gear case member having a first bearing means therein for supporting the output gear, and second and third bearing means therein for supporting either the intermediate gear means or the input gear, said first, second and third bearing means in the second gear case member being located on axes defining an equilateral triangle equal to the first gear case equilateral triangle and being coincident therewith, said equilateral triangle having apexes lying in a common circle having a center, and fastening elements on the first gear case member and the second gear case member spaced 120 degrees apart with respect to said center so that the first gear case member may be positioned in either of said first and second positions.

A gearbox for obtaining the proper drive ratio between a driven element in a vehicle drive train and a speedometer or odometer, comprising;

• a first generally cup-shaped gear case member, said first gear case member having first, second and third bearing means therein having axes arrayed in triangular configuration, a second generally cup-shaped gear case member connected to said first gear case member and having first, second and third bearing means therein having axes arrayed in triangular configuration coincident with the triangular configuration of the axes in the first gear case member, input gear means supported in the first bearing means in the first gear case member and the third bearing means in the second gear case member, intermediate gear means engaging and driven by the input gear means, said intermediate gear means being supported in the second bearing means in the first gear case member and the second bearing means in the second gear case member, and output gear means engaging and driven by the intermediate gear means, said output gear means being supported in the third bearing means of the first gear case member and the first bearing means of the second gear case member, said first and second gear case members being shiftable so that the first, second and third bearing means in the first gear case member and the first, second and third bearing means in the second gear case member are positioned to alternatively permit the input gear means to be supported in the first bearing means in the first gear case member and the second bearing means in the second gear case member, the intermediate gear means to be supported in the third bearing means in the first gear case member and the third bearing means in the second gear case member, and the output gear means to be supported in the second bearing means in the first gear case member and the first bearing means of the second gear case member.

A gearbox for obtaining the proper drive ratio between a driven element in a vehicle drive train and a speedometer or odometer, comprising;

• a first generally triangular cup-shaped gear case having first, second and third bearing means therein located on axes defining an equilateral triangle, a second generally triangular cup-shaped gear case having first, second and third bearing means therein located on axes defining a second equilateral triangle equal to and coincident with the first equilateral triangle, said equilateral triangles having apexes located on a common circle defined about a center, locating means on the first and second gear cases permitting the second gear case to be located with respect to the first gear case in 120 degree spaced positions with respect to the center, an input gear assembly including an input shaft supported in the first bearing means in the first gear case and one of the second or third bearing means in the second gear case, an input gear on the input shaft, an intermediate gear assembly including an intermediate shaft mounted in one of the second or third bearing means in the first gear case and one of the second and third bearing means in the second gear case, a first intermediate gear on the intermediate shaft engaging and driven by the input gear, a second intermediate gear on the intermediate shaft, an output gear assembly having an output shaft supported in one of the second and third bearing means in the first gear case and the first bearing means in the second gear case, and an output gear on the output shaft engaging and being driven by the second intermediate gear, said first gear case being selectively positionable with regard to the second gear case in two 120 degree spaced positions to reverse the positions of the input gear assembly and the output gear assembly relative to the intermediate gear assembly.

A gearbox for obtaining the proper drive ratio between an input shaft and an output shaft, comprising;

• an input housing member and an output housing member, fastening means for the housing members that selectively connects the housing members together in either of the first and second 120 degrees angularly spaced positions, said member means having a geometric axis common to both of the connected positions thereof, an input gear bearing and first and second bearings in the input housing member all having axes lying on a common circle having a center on the geometric axis of the housing members, an output gear bearing and third and fourth bearings in the output housing member all having axes lying on a common circle also having a center on the geometric axes of the housing members, an input gear assembly rotatably mounted at one end in the input gear bearing in both the first and second positions of the housing members and at the other end in the third bearing in the first position of the housing members and the fourth bearing in the second position of the housing members, an output gear assembly rotatably mounted at one end in the output gear bearing in both positions of the housing members and at the other end in the first bearing in the first position of the housing members and in the second bearing in the second position of the housing members, and an intermediate gear assembly interengaging both the input gear assembly and the output gear assembly and rotatably mounted at one end in the fourth bearing in the first position of the housing members and in the third bearing in the second position of the housing members, and at the other end in the second bearing in the first position of the housing members and in the first bearing in the second position of the housing members.