U.S. Philips Corporation

Hauni Maschinenbau Ag

Korber Ag

Dierk Schroder

Bernd Heck

Dirk Sacher

Norbert Hohenstein

Siegfried Hapke

Peter Straube

Gunter Jurgens

Uwe Westphal

The diameters of successive rod-shaped articles of the tobacco processing industry are ascertained while the articles advance sideways at the periphery of a rotary drum-shaped conveyor and are rotated about their longitudinal axes as a result of frictional engagement with a rolling member which is adjacent the periphery of the conveyor. Successive articles which are being rotated by the rolling member are caused to interrupt a beam of radiation issuing from a laser, either once or more than once, and the amounts of intercepted radiation are indicative of the diameters of the respective articles. Such amounts of intercepted radiation are monitored by a video camera which generates electric signals, and the electric signals are processed into second signals denoting the diameters of discrete successively tested articles and/or the average diameters of series of two or more successively tested articles.

Method of and apparatus for measuring the diameters of rod-shaped

Successive rod-shaped articles of the tobacco processing industry are conveyed transversely of their length along an arcuate path while advancing through a testing station wherein they are urged to impinge upon one or more sensors under the action of centrifugal force. The sensor or sensors transmit corresponding signals to one or more transducers which, in turn transmit signals to a processor wherein the signals are converted into signals denoting the actual weight of the tested articles. The apparatus can utilize piezoelectric transducers or other types of transducers, e.g., one or more extensometers.

Method of and apparatus for determining the weight of rod-shaped

The resonance frequency and/or damping of a high-frequency oscillator which contains a variable impedance (such as a capacitor in a moisture detector for coffee or tobacco) is ascertained by generating first signals which denote the envelope curves of oscillations during intervals between successive excitations of the oscillator. Pairs of second signals denoting predetermined portions of envelope curves are transmitted to a dividing circuit, and the quotients of such pairs of second signals are indicative of the damping. Resonance frequency is ascertained by counting the number of oscillations per interval. Oscillations of the oscillator can be rectified prior to the generation of first signals.

Method of and apparatus for ascertaining a characteristic value of a

A measuring oscillator for detecting different physical parameters has an all-pass filter (1) which drives a current source (16) having a controllable amplification factor and a control device (17). The control device is connected to the control input of the current source (16) and controls its amplification factor so that the amplitude of the alternating voltage produced by the measuring oscillator assumes a constant value. The all-pass filter comprises a phase-determining bipolar circuit (10) comprising a voltage follower (12) having its input connected to the first pole (9) of the circuit (10) and its output connected through bridge circuit (28) to the inputs of a differential amplifier circuit (33). The four resistance elements (29-32) of the bridge circuit have resistance values varying with the physical parameters to be detected. The output of the differential amplifier circuit is connected through an ohmic resistor (41) to the first pole. The second pole (11) of the bipolar circuit (10) is connected to the junction of the two resistance elements (31, 30) of the bridge circuit. A variation of a resistance element of the bridge circuit due to a variation of the physical parameter detected by it results in a readily measurable variation of the frequency of the measuring oscillator.

Oscillator having all-pass filter with resistance bridge for detecting

A measuring oscillator for measuring temperature has an all-pass filter (1) which drives a current source (16) having a controllable amplification factor and a control element (17). The control element is connected to the control input of the current source (16) and controls its amplification factor in a manner such that the amplitude of the alternating voltage produced by the measuring oscillator assumes a constant value. The all-pass filter comprises a phase-determining bipolar circuit arrangement (10) comprising a voltage follower (12), whose input is connected to one terminal (9) of the circuit arrangement (10) and whose output is connected through an ohmic input resistor (13) to the inverting input of a first operational amplifier (14), which is fed back negatively through a measuring resistor (15) having a temperature-dependent ohmic resistance value. The output of the first op-amp also is connected through an ohmic resistor (41) to the one terminal (9) of the bipolar circuit arrangement. The non-inverting input of the first op-amp is connected to the other terminal (11) of the bipolar circuit arrangement. Small temperature variations sensed by the measuring resistor lead to comparatively large adequately measurable variations of the frequency of the measuring oscillator.

Growing community of inventors

Hamburg, Germany

Dierk Schroder