Abstract: A tablet compressing machine includes strain gauge sensors 5, 5' for monitoring the forces applied to piston rams 1, 2 by pressure rollers 3,4. The strain gauges are connected in a bridge circuit whose amplified output is fed to a mean value generator 15 and a logic control unit 9. The former generates a mean pressing force curve (A in FIG. 3) while the latter causes preset individual limit values for the pressing force signals (B, C in FIG. 3) to track fluctuations in the mean value curve, and compares the instantaneous pressing force signals with the individual limit values. Whenever these limit values are exceeded or fallen below the machine is disabled and the faulty ram is indicated on a display 14 by means of a sensor 7 which signals the ram being monitored. Means are also provided for disabling the machine whenever the mean value exceeds or falls below adjustable tolerance limits.

Abstract: A protective hood for a tablet compressing machine includes a heavy cover plate 12 resiliently supported on the top of the machine frame 11, vertical support members 14, hinged windows 16 secured to the support members by locks 21, and acoustical absorption plates 15 above and below the windows. Environmental integrity is implemented by channel members 17 around the edges of the support members and provided with chambers 18 kept at a positive pressure through inlets 19. The chambers are closed by rubber seals 20 around the edges of the windows 16.