Patent GB-651850-A (GB)
Title: A new or improved apparatus for pressure testing valves or cocks for controlling the flow of fluids
IPC: G01M3/28
Filed: 1947-09-15
Abstract: 651,850. Testing hollow-ware for leaks. EVERED & CO., Ltd., and KEIGHT, J. J. Sept. 15, 1947, Nos. 25154/47 and 17238/48. [Class 106 (ii)] [Also in Group XXIX] Apparatus for testing hollow articles such as valves and cocks in which the work or article to be tested is subjected inside to compressed air and then immersed in a liquid to detect any leakage of air, comprises fluid pressure operated work supporting means, fluid pressure operated work gripping means, means for introducing compressed air into the work to be tested and valves means for controlling the operation of both the fluid pressure operated means and for admitting  compressed air to the interior of the work. The work gripping means are controlled by a separate valve mechanism operated independently of the valve mechanism controlling the work supporting means and the supply of compressed air to the interior of the work. In Figs. 1 and 3, the work supporting means comprises two parallel beams 15 mounted on a rotatable shaft 12 supported in bearings on a tank 10 mounted on a stand 11. Each beam 15 carries two brackets 16, 17. The bracket 16 supports a fixed clamping member 18 having a projection 19a, and a sealing disc 19. The bracket 17 slidably supports a tubular rod 20a carrying a movable clamping member 20 with a sealing disc 21 and a bore 21a in register with the bore in the tubular rod 20a. Each rod 20a is connected to the piston-rod 22 of a double-acting cylinder 23 connected by flexible pipes 24 to a valve mechanism 25 operated by a pedal 25a. The shaft 12 is connected to a sprocket-wheel 26 to which is fixed a chain 27 attached to the piston-rod 28 of a piston and cylinder mechanism 29. Compressed air is admitted to the upper end of the cylinder 29 under the control of a valve mechanism 30 which also controls the supply of compressed air through a flexible pipe 31 to the tubular rods 20a. A pressure gauge 32 is fitted in the pipe 31. In operation, two valves 33 to be tested are placed between the sets of clamping members 18, 20 which are then moved into clamping relation by depressing the pedal 25a. The valve mechanism 30 is then operated to admit compressed air to the inside of the valves 33 and at the same time vent the cylinder 29 so that beams 15 dip into the tank under the action of gravity. When the test has been made, the valve mechanism 30 is operated to cut off compressed air from the valves 33 and admit it to the cylinder 29 to raise the beams 15. Thereafter the valves 33 are unclamped by releasing the pedal 25a. One or both of the clamping members may be made adjustable so that they cannot be moved completely together to trap the hands of an operator. Conveniently two sets of apparatus are arranged on one tank for working by operators on either side thereof. Fig. 7 shows a modification suitable for larger valves such as 33a. A carrier member 39 is slidable on rods 34 and is raised by a chain 38 passing over a sprocket-wheel 37 supported on the rods 34 by fixed brackets 35. The chain 38 is fixed to a larger sprocket 55 fixed to a shaft 56 bearing a further sprocket 57. The shaft 56 is rotated by a small chain 58 fixed to the sprocket 57 and to the piston-rod 59 of a piston and cylinder mechanism 61 supplied with compressed air under the control of a valve mechanism 54 to raise the carrier member 39. The latter carries a pair of brackets 46, 47 and has a number of steps 39a in one of which is fixed a platform 40 carrying the fixed clamping member 42. The .movable clamping member 52 has a central .bore 53a and is connected to the piston-rod 50 of a cylinder 48 supported in the bracket 46. The cylinder 48 is supplied with compressed air to raise and lower the clamping member 52 by a pedal-operated valve mechanism (not shown). Compressed air is admitted to the bore 53a through a cylinder 49 held in the lower bracket 47 and supplied through a pipe 51 by the valve mechanism 54. The apparatus may be used for testing hydraulic cylinders such as those of vehicle brakes.