A device for measuring the displacement of a part of a machine for example a lathe, cylinder grinding machine, or the like machine

摘要

680,825. Grinding-machine details. AKTIEBOLAG ESSESS. Nov. 30, 1949, No. 30727/49. Class 60. [Also in Groups XIX, XXII and XXXV] A device for measuring the displacement of a part of a machine, e.g. a lathe or a cylinder grinding machine, comprises a pair of rollers 21, 22 mounted on the displaceable part or on a fixed part of the machine and adapted to grip between them a band 17 secured between two fixed points on the machine or to the displaceable part respectively, so that an indicator connected through a transmission means to the roller 22 is caused to register the distance said roller rolls along the band or the displacement of the band if this is moved. In the embodiment illustrated, the device is mounted on the displaceable part by means of lugs 11 and indicates the extent of displacement with fingers 14, 14a on a graduated dial 13. Flanged rollers 23, Fig. 4, mounted in a carrier 241 for the roller 22, guide the band 17 between the rollers 21, 22 and out of contact with the roller 22. The roller 21 is mounted on a lever 34 hinged at 35 to the carrier and retained against the compression of a spring 36 by a toggle linkage 39, 40 in which the links 40 are pivoted at 41 and engage a pin in the end of link 39. A further link 43 connects the links 40 to a bellcrank lever 421, Fig. 2, attached to the armature 45 of an electromagnet 46 adapted, upon energisation, to rock the lever 421 against a spring 47 secured thereto and so upset the toggle linkage and allow the spring 36 to grip the band 17 between the rollers 21, 22. Upon being upset, the link 40 engages a lever 48, Fig. 4, which rotates its shaft 49 and causes a catch 57, Fig. 6, mounted thereon to release a locking plate 53 carried by a spindle 24 secured to the roller 22. The spindle 24 transmits rotation of the roller 22 through gearing 25, 26, 28, 31, 29, 32, Fig. 2, to a spindle 30 carrying the finger 14a and to a hollow, spindle 33 supporting the finger 14. Back-lash is taken up in the gear train by a uni-direction induction motor 55 (see Group XXXV) which also returns the fingers when the electromagnet is de-energised. The catch 57 is then caused by a spring 54 to relock the transmission. In alternative forms, back-lash may be taken up by a coiled spring slipping with constant friction on the spindle 30, and the electromagnet may be replaced by hydraulic or mechanical means.