Patent GB-191202842-A (GB)
Title: Improvements in Steam Hydraulic Instensifiers.
IPC: B21J9/12
Filed: 1912-02-03
Granted: 1912-11-28
Abstract: 2842. Davy Bros., and Holmes, T. E. Feb. 3. Intensifiers. - In a steam hydraulic intensifier used in conjunction with an hydraulic press, valved connexions are used to enable the steam which effects or assists the initial descent of the press ram to pass into the steamcylinder of the intensifier. The Figure shows the apparatus applied to a steam intensifier hydraulic press embodying features set forth in Specifications 781/05, 18,329/05, 23,628/05, and 16,609/07. The press ram 4 is attached to the press head 3, which is worked by the ram 4 and lifting-pistons 7, 7. The piston 10 works in the steam-cylinder 9, and the rod 11 is prolonged to form a ram 12 working in the hydraulic cylinder 13. The hydraulic pressure main 14 leads from the cylinder 13 to the cylinder 5 and to the air-vessel 16 through a valve 17. The main. steam-supply pipe 18 communicates through the valve 56,55 with the pipe 53 leading to the tops of the retracting- pistons 7, and permanently communicates with the bottoms of these pistons by the pipe 51. The pipe 51 is in communication through the valve 55 and a non- return valve with the steam chamber of the intensifier. Steam also enters the steamchamber o f the intensifier through the pipe 18, valve 20. and pipes 22, 19. Thesteaminlet valve 20 and the exhaust valve 21 are controlled on the one hand manually by means of the lever 24 and on the other hand automatically by means of hunting- gear governed by the piston 10 substantially in the manner described in Specification 781/05. For this purpose, the stems of the valves 20, 21 have pin-and-slot connexions 27, 28 with the lever 29 pivoted at 30. The valve 20 is loaded to compensate for the differential area due to the valve - rod. T h e lever 29 is connected to the lever 33, which is acted upon by the hand-lever 24 and by the lever 36 of the automatic control device. Assuming the ram 4 to be raised, then when the lever 24 is moved from position a to position b, the valve 20 is opened and pressure-water is forced into the cylinder 5, until, as the piston 10 approaches that point in its travel which corresponds to the point at which the hunting- lever 24 is held, the valve 20 is automatically closed, and the motion of the piston 10 is arrested. The hand-lever 24 is coupled to the valve 17 by pin-and-slot and lever mechanism, so that the valve may be opened positively without interfering with the automatic opening. The arrangement is such that, when the lever 24 is moved from a to d to open the exhaust valve, the valve 17 is also lifted from its seat so that any surplus water may be forced into the air-vessel 16. The duplex piston valve 55, 56 controlling the passage of steam to and from the cylinders 6 is capable of occupying the normal or lowered position where it closes the communication between the pipes 18, 53 and establishes communication between the pipes 53, 58, and the raised position (shown in the Figure) where it establishes connexion between the pipes 18, 53 and closes communication between the pipes 55, 58. The valve 55, 56 tends to assume its lowered position by gravity and spring pressure, and is detachably coupled to the hand-lever through the medium of trip mechanism consisting of a plunger 62, socket 61, recess 63, and spring latch 64. The arrangement is such that when the valve 55, 56 is in its lowered position and the lever 24 in the position c, the plunger 62 descends so far as to permit the latch 64 to enter the notch 63, so that when the lever 24 is afterwards returned to the position a, the socket 61 and the valve 55, 56 rise to the highest position. Further upward movement of the socket 61 causes the lever-and-link gear 66, 68 to withdraw the latch and allow the valve 55, 56 to drop back to its normal or lowered position. Assuming the valve 55, 66 to be in its lower position, steam is cut off from cylinder 9 and pipe 53, but is allowed to act upon the lower surfaces of the piston 7 to raise the ram, and when the lever 24 is moved to the position d, to operate the valve 17. To further operate the press, the lever 24 is advanced to the position c so that the rod 62 may engage with the valve spindle, and the valve 55, 56 is raised by returning the lever 24 to the position a. Steam then acts upon the piston 7 to lower the ram 4 to the work. A further movement of the lever 24 to the position e causes the disconnexion of the rod 62 and valve spindle and the cutting-off of steam from the pipe 53. The steam already admitted through this pipe expands and acts upon the intensifier piston 10 so that the press-head effects the initial compression of the work. By a further movement of the lever 24 to the position b, live steam is admitted to the cylinder 9 and the compression of the work completed. On the completion of the working stroke, the lever 24 is returned to the position a, the steam supply cut off, and the exhaust valve 21 opened. The steam from the pipe 53 exhausts through the valves 59, 21.