Abstract: In the tire testing method before and after an alteration in the tire pressure a respective interferogram is produced of the tire surface using coherent radiation and the interferogram is used to obtain an information concerning any defects present in the tire is obtained.

Abstract: The invention concerns a device for balancing a wheel comprising a rim and a tire. This device comprises a unit for measuring the wheel imbalance and a unit for scanning the rim dimensions. The scanner unit and the imbalance-measuring unit are connected to a computer which determines a rim contour from the scanner unit output signals and then the optimum positions and dimensions for the balance weights from the contour determined in conjunction with values supplied by the imbalance-measuring unit.

Abstract: In a balancing apparatus, for determining the compensation position and the magnitude of a compensation weight to be attached to the automotive wheel on the basis of the measuring values obtained during the balancing process, the respective radius and the respective compensation plane for the compensation position at the automotive wheel are sensed via a sensor arm, an electronic device determines the magnitude of the compensation weight to be attached to the automotive wheel. The sensor arm is supported extendably and pivotally. Two string assemblies are attached to the sensor arm. The strings of the sensor arm are mechanically lockable at one or the other compensation position, respectively. One of the string assemblies on the sensor arm comprises an extendable spring and a stop which runs through a locking block attached to the housing of the balancing apparatus and and also comprises, at the other end an extendable spring.

Abstract: A tire testing device comprising an air pressure control means for changing the tire pressure of a wheel, a test head and a computer, which prior to and after a change in the air pressure produce an interferogram of the tire surface and convert the interferogram into a modulo-2.pi.

Abstract: In the tire examination method before and after an alteration in the tire pressure a respective interferogram is produced of the tire surface using coherent radiation and the interferogram is converted into a modulo 2 .pi. image, which for its part is processed to obtain a gray value image and in the case of which from a comparison of the gray value images information concerning any defects present in the tire is obtained. For testing a tire the wheel, which bears such tire to be tested, is arranged on a driven roller set by driving the vehicle with the wheel, a test head is moved toward the tire to be at a predetermined test distance therefrom for producing such interferograms, at a first test segment of the tire examination for defects is performed, the wheel is incrementally rotated by the roller set by an amount equal to the size of a test segment and so many test segments are examined that the complete tire is tested.

Abstract: In the tire examination method before and after an alteration in the tire pressure a respective interferogram is produced of the tire surface using coherent radiation and the interferogram is converted into a modulo 2.pi. image, which for its part is processed to obtain a gray value image and in the case of which from a comparison of the gray value images information concerning any defects present in the tire is obtained. For testing a tire the wheel, which bears such tire to be tested, is arranged on a driven roller set by driving the vehicle with the wheel, a test head is moved toward the tire to be at a predetermined test distance therefrom for producing such interferograms, at a first test segment of the tire examination for defects is performed, the wheel is incrementally rotated by the roller set by an amount equal to the size of a test segment and so many test segments are examined that the complete tire is tested.

Abstract: A method for single-knob operation of a balancing machine is characterized by a program-controlled run of the balancing process which is controllable in steps via a single-knob control element. In this method, operating the single-knob control element at predetermined steps of the program triggers functions which depend on the current status of the program-controlled run. A single-knob control element is provided for carrying out the method.

Abstract: A balancing machine for balancing a wheel, wherein the wheel is rotated by a drive device for measuring the unbalance, is provided with a speed control device for controlling the speed of the drive device. The speed control device includes a computer and a frequency converter. Further drive devices can be switched by a switch-over device.