Patent GB-1210353-A (GB)
Title: Apparatus for guiding an operating member
Inventor: SCHAPIRO JOACHIM ISRAEL
IPC: B43L13/02
Filed: 1966-10-31
Abstract: 1,210,353. Draughting machines. J.I. SCHAPIRO. Jan.31, 1968 [Oct. 31, 1966], No. 48775/66. Heading G1X. Apparatus for guiding an operating member, e.g. a drawing stylus 101 Fig. 5 comprises a function generator, i.e. a device which may be set to constrain an axis 51 of the device to move in straight lines or circular arcs, the movements of the axis 51 of the generator being resolved by a series of cables and pulleys into x and y movements represented by corresponding movements of an x carriage 122 and a y carriage 142, these movements being transmitted to a carriage 102 to cause the stylus 101 to draw the desired function line, each of the carriages 122, 124 being provided with a releasable coupling 123, 143 to clamp a corresponding cable against movement relative to the carriage, whereby when the couplings 123, 143 are released the function generator and/ or the stylus may be moved independantly in order to reset the function generator or when it is not desired to move or draw with the stylus 101. The carriage 102 is mounted on a track 100 for movement in the x direction and the track 100 is itself movable in the y direction on tracks 110. Similarly movements of the axis 51 of the function generator are allowed by the provision of tracks 80 and 90. Motors 125, 145 drive the cables for the x and y directions respectively and thus if the function generator is set to constrain the axis 51 to move along a desired path, then the stylus 101 will trace out this path over the drawing surface 104. The function generator is shown in Fig. 1 and comprises three tracks 20, 30, 40 supported on a table 10 for pivotal movement about axes 21, 31, 41 respectively. Carriages 22, 32, 42 are supported for movement along the tracks 20, 30, 40 and the carriages are connected together for pivotal motion relative to each other about the axis 51. The table 10 is rotatable on a base 12 but may be prevented from rotation by operation of a lock 13. A lock 23 is provided to hold the track 20 at right angles to the track 30 in the zero position and a lock 33 may be used to hold the tracks 30, 40 parallel. Sliding movement of the carriages 22, 32 along the tracks 20, 30 may be prevented by use of locks 24, 34 and a lock 53 is provided to prevent relative rotation between the carriages 32, 42. All the locks are preferably actuated electro-magnetically. By release of the locks 24, 33, 34, 53 the carriage 22 may move along the track 20 to generate an x direction movement. Similarly by release of the locks 23, 24, 34 the carriage 32 may be moved along the y direction track 30. Also by moving the carriages and thus the axis 51 to a desired radius from the zero position the table 10 may be rotated after release of the lock 13 to generate a circle. Radii and tangents to the circle may then be generated by operation of the appropriate locks. Arcs of a radius greater than that of the table 10 may be generated after setting the carriage 22 on the track 20 after release of the lock 33 at the desired arc height, then setting the lock 53 and releasing the locks 23, 24, 34. Movement of the carriages in the y direction will then result in arcuate movement at the desired radius. Tangents and radii to these arcs may also be generated using co-operating parts 60, 61, 62, 63, 64 as described in the Specification. (For Figures see next page)