| 摘要 |
<p>911,363. Testing brakes. DUNLOP RUBBER CO. Ltd. May 4, 1959 [May 8, 1958], No. 14709/58. Class 103 (1). [Also in Groups XXIX and XL (b)] Apparatus for regulating the pressure supplied to a fluid pressure-operated mechanism, e.g. a brake, in accordance with test requirements in the form of a curve plotted between two variables, eg. speed and braking torque, includes an oscilloscope 18 having on its screen a mask 22 having an edge shaped in conformity with the test curve. The beam of the oscilloscope is moved in response to the two variables and if it moves clear of the mask, a light-sensitive cell 24 operates to effect control of the fluid pressure supplied to the mechanism. In Fig. 2, a wheel 10 fitted with a brake is driven by an inertia wheel 11 which also drives a D.C. tacho-generator 21 which supplies the oscilloscopes 17, 18 with a signal representative of the speed. An arm 12 bears against a pressure capsule 13 which provides a signal representative of the torque. The oscilloscope 17 gives a visual indication of whether the brake is conforming to the test. The signal from the light-sensitive cell 24 is fed through an amplifier 25 to a solenoid 35 which adjusts a tube 32 emitting a stream of fluid towards an outlet 30 and the resultant pressure is conveyed through outlet 30 to adjust the brake. The solenoid may be coaxial with the tube and be associated with a cam contacting a cam surface in the end of the tube. In a further modification, the amplifier 25 actuates a splitfield motor connected to the tube 32 through a reduction gearing.</p> |
