Patent GB-481591-A (GB)
Title: Improvements in copying machines
IPC: B23Q17/24
Filed: 1936-07-09
Abstract: 481,591. Copying-machines. TAYLOR, M. H., and KAPELLA, Ltd. July 9, 1936, No. 19001. [Class 60] [Also in Groups XVI and XXII] A copying-machine for reproducing, on a reduced scale, the outline of a template or drawing on a work-piece by means of a grinding-tool, a milling-tool, or a stylus &c., comprises an optical system for forming an image of the drawing &c., a microscope for viewing the image, means for imparting relative movement to the image and the microscope whereby the device can trace the outline of the image and means whereby such relative movement is caused to control relative movements between supports for the tool and the work. The machine, which also is adapted to be used with a tracer moving over a copy without the optical means, comprises a base A having pivoted thereon on an axis B the primary link B<1> of a pantograph having links B<2>, B<3>, B<4> with pivots on axes B<5>-B<8>, the axis B7 forming the work shaft axis, and the copy shaft axis B<9> being in the link B<3> at such a position that the axes B, B<7>, B<9> are coplanar. The support for the usual tracer consists of a bracket C<1> on the base A, and the tool comprises a grinding-wheel D on a shaft parallel to the plane containing the axes B, B7, B<9> when in the zero position, the wheel being driven by gearing from a motor on the head D<5> of a plunger movable up and down in part of a cross slide E, which also may be adjustable angularly on a guide E<9> to give a rake to the work. The wheel is adjusted with the aid of a microscope F carried by a bracket F<1> on link B<2> with its axis coincident with the axis B<7>. The work support comprises a table H<1> on a shaft rotatable on the axis B<7> and surrounded by a splash guard H<2>, and the copy support comprises a table formed in two parts J<2>, J<3>, the lower part J<3> being carried on a shaft rotatable in the link B<3>. The table J2, J3 and the work table H<1> are geared together by spur gearing contained in casings K, K<1> so that they may rotate synchronously when the table J<3> is turned by a disengageable hand-wheel M ; thus datum axes on the work and copy tables will always remain parallel to one another. In order that the datum axes, in addition to remaining parallel, also may remain parallel to a fixed direction, a linkage is provided comprising an arm L on the axis B<7> connected by a link L<1> to one arm L<2> of a bell-crank lever pivoted on the axis B<5> and the other arm L<3> of which is connected to a link L4 which can swing about a fixed pivot point L<5> on the frame A ; to bring this linkage into operation, the arm L is clamped to the work shaft. In using the optical magnification to obtain a greater ratio between the size of the copy and of the work, the drawing used as a copy is fixed. The board O. upon the underside of which the drawing is mounted, is secured, so as to be adjustable in two directions, to bars Q by means of clamps O<1>, the bars Q being supported at a height above the copy table by a framework P, P<1>, P<2>, Q<1>, Q<2>. A lens R is mounted beneath the board O upon a block R<1> carried by struts R<2>, R<3>, R<4> and forms an image of the drawing in a horizontal plane S a short distance above the copy table J<2>, the image being viewed by a microscope T clamped to the table and provided with a reflecting device and a lateral eye-piece T<1> ; a ground glass &c. screen may be provided in the image plane S. Thus if the optical magnification ratio is 3 : 1 and the ratio of the pantograph is 5:<1>, a total magnification of 15 : 1 is obtained. During operation, the microscope is sighted on and traverses the outline of the drawing, the pantograph, if desired being clamped in each position on the outline before taking a cut ; or, to avoid resetting the drawing when dealing with work to be ground &c. on all sides, the drawing may be mounted on the copy table, the microscope being fixed. Specification 481,658 is referred to.