Machines for measuring plain rings, screw ring gauges and like articles

摘要

610,747. Gauging-apparatus. MOLLART ENGINEERING CO., Ltd., MOLLART, K. A., and HARRIS, S. E. April 15, 1946, No. 11551. [Class 106 (ii)] Apparatus for measuring plain or screwthread diameters comprises a base 1 on which a work table 2 and a fixed anvil 13 are mounted, a carriage 9 slidable on the base carrying a micrometer head 12 which co-operates with the anvil 13, a measuring point 20 (not shown) mounted on the carriage to engage the work as a result of operation of the micrometer head, and means on the work table to align the axis of the work with a particular fixed axis set perpendicularly to the direction of travel of the carriage. The table 2 is rotatably mounted about a vertical axis, and to enable the axis of the work placed thereon to coincide with this vertical axis, the table is carried by two cross slides adjustable by screws 7, 8. The work may be retained on the table by clips, or permanent or electro-magnets. The carriage 9 and base 1 are formed with oppositely arranged grooves in which are mounted steel balls. A support 11 on the carriage carries the micrometer head 12 which abuts the anvil 13 carried by a support fixed on the base 1. The carriage is cut away at 15 surrounding the supports for the table and micrometer. A support 16 on the carriage supports the tubular extension 17 of a light alloy housing 18 carrying a lever 19 housing a downwardly depending measuring stylus 20 (not shown) adapted to enter the bore, or engage the outside, of the work on the table 2. The lever 19 is fulcrummed to the housing at 21, and its opposite end 22 engages a fixed cam 23. The housing 18, together with the lever 19 can be angularly adjusted in the support 16, and the fixed cam 23 compensates the angular movement of the stylus 20 over a small movement. The housing is counterbalanced at 24. The compensating cam 23 is carried by a spindle 25 terminating in a fiducial head 26 of known construction which ensures that the stylus 20 engages the work being measured with a predetermined force. Operation of the micrometer 12 contacting the fixed anvil 13 moves the carriage 9 relatively to the base 1 and the table 2, and contact of the stylus with the work is indicated by the pointer 27 in the head 26. The single measuring stylus 20 is suitable for measuring internal diameters of small dimensions, and the compensating cam 23 enables measurements at different depths (or heights) to be made. For screwthread measurements the stylus has a ballpoint. In a modification, the work table 2 can be adjusted vertically, and the measuring stylus merely mounted for sliding movement in the direction of the axis of the spindle 25.