GB718258A - Improvements in or relating to a strain gauge for forging press - Google Patents

Abstract

718,258. Dynamometers. NATIONAL MACHINERY CO. Dec. 30, 1952, No. 32961/52. Class 106 (2) A strain gauge of the type in which the load in a forging press 1 is measured by the strain in the frame comprises a bar 10 pivotally anchored at 8 in line with the axis 7 of the crank shaft 3, and co-operating at its lower end with an indicator 13 carried on a fixed mounting 12 so that movement of the bar 10, when the frame ,of the press is elongated with the strain, is transmitted to the dial indicator 13 through an amplifying lever system. The lower fixed support 12 is provided with a mounting 12a for the dial indicator 13, the movable member of which 16, is in contact with one end of the lever 18. The lever 18 is pivoted on the lower end of the bar 10 at 19 and the end of the -lever 18 remote from the indicator member 16 is urged into contact with a fixed pin 14 in the frame of the press by a spring 20. The bar .10 is provided with a large clearance hole 15 so that the movement of the bar 10 is not prevented by the pin 14. Movement of the bar 10 causes displacement of the pivot 19 of the lever 18 relative to the fixed pin 14 and thereby causes partial rotation of the lever 18 with consequent .linear displacement of the dial indicator member 16. The magnitude of the movement of the lever 18 and dial indicator member 16 may be varied by adjustment of the bar 10 in relation to the fixed stop 14 thereby varying the ratio of the turns of the lever 18. Adjustment of the arm 10 is effected by means of a clearance aperture 21 into which penetrate two adjusting screws 23, 24, co-operating with a fixed pin 22 on the frame of the press which also .penetrates into the clearance aperture 21.