US2660955A - Hydraulic machine - Google Patents

Description

1386- 1, 1953 F. J. KENT ET AL 2,660,955

HYDRAULIC MACHINE Filed June 27, 1950 5 Sheets-Sheet l T)ME DELAY I I IN VEN TOR.S FRRNC/J \J. KEN 7- Dec. 1, 1953 Filed June 27, 1950 F. J. KENT ET AL 2,660,955

HYDRAULIC MACHINE 3 Sheets-Sheet 2 Dec. 1, 1953 Filed June 27, 1950 F. J. KENT ET AL HYDRAULIC MACHINE 5 Sheets-Sheet 5 Patented Dec. 1, 1953 HYDRAULIC MACHINE Francis J. Kent and Reymond M. Reichl, Forest Hills, N. Y York, N. Y

Application June 27,

This invention relates to fluid pressure operated machines and especially to pressure changing mechanism suitable for use therein such as in hydraulic testing machines for tubes, pipes, or the like.

Hydraulic mechanism for increasing pressure is known, such usually comprising a large cylinder with a ram or piston and a small cylinder with a ram or piston, the pistons being coupled to each other. In such an instance, when low pressure fluid is delivered to the large cylinder, the pistons will move together and fluid of higher pressure will be developed from the-high pressure cylinder.

cuits can be arranged so as to automatically provide the desired cycle of movement of the intensifiers.

In another aspect of the invention, two pumps can be employed for supplying the low pressure fluid to the intensifiers. large main pump and'the other a smaller auxiliary One of these may be a assignors to Hydropress, Inc., New a corporation of Delaware 1950, Serial No. 170,624 8 Claims. (61. 103-45) where the low pressure side is driven by oil and the high pressure side involves water.

These and other advantages, objects and features of the invention will become apparent from the following description and drawings.

In the drawings:

Figure 1 illustrates schematically one form of Figure 3 is similar to Figure 2 with the exception that the right hand piston has moved fur- Figure i is generally similarto the preceding figures with the exception that one of the valves has moved so that the right hand piston can move downwardly while the left hand piston is on its power stroke.

Figure 5 is an enlarged view, partially in sec,- tion, showing one form of a twin cylinder intensifier.

Figure 6 is a fragmentary top view of Figure 5.

Referring first to Figure 1, the twin intensifier arrangement it has a right hand unit HA and a left hand unit iiB. Rams IZA, i213 have high pressure portions 83A, sure portions iA and MB. Said rams operate in high pressure cylinders 55A, 15B and low pressure cylinders 16A, HEB, respectively.

n The highpressure cylinders have outlets 17A,, ilB leading to the high pressure connection 33 through suitable check valves 20, 20. Water can be supplied to the system through the suction check valves l9, l3. Limit switches 21A, 2|B, 23A, and 23B are placed along the cylinder and are operative according to the position of the rams. These switches are connected through schematically illustrated wires 24,, 25 with the master controller 2%, said master con-- troller in turn being connected to the solenoids of the various control valves as will be explained hereafter. The master controller can have a suitable start push button associated therewith.

The motivating pressure source for the intensifier can comprise pump unit 21. employing a main pump 23 and an auxiliary pump 2.9, said pumps. being driven by a suitable electric motor 3 The main oil pump 28 preferably is" of the variable delivery type and the pressure therefrom is used for the main compression or upward movement of both of the intensifier units. This pump may be provided with an automatic control so that delivery volume is reduced when a predetermined outlet pressure is reached;

The auxiliary pump can be smaller than the main pump and used for the precompression movement in each of the intensifiers as well as for the return movement of the rams. This pump may be of the constant delivery type but preferably is of the variable delivery type similar to the main oil pump. The main oil pump is connected by means of pipe 31 to the main four- The auxiliary pump 29 is connected by pipe 33 with the main four-way control valve 32, which control valve may take various forms. In the form schematically shown, it is operated by means of solenoid 34 which positions the valve stem 35 as desired in valve body 36, the solenoid being controlled by the master controller 26. The secondary four-way control valve 31A controls the flow of fluid to and from the right hand intensifier unit I IA, and the second secondary fourway control valve 313 controls the flow of fluid to and from the left hand intensifier unit HB. Secondary control valves 31A and 3113 have solenoids 38A and 383 connected with the master controller 28 in such a manner as to position valve stems 39A and 393 as called for by the control circuits.

The pumps are suitably connected with the oil storage tank 40, said storage tank having pipe 4! connected thereto for receiving liquid from the return ports of the secondary four-way valves.

The main control valve 32. serves as the switchover valve for changing main operating pressure from one intensifier unit to the other. The secondary control valves 31A and 31B serve to control the reversal of flow of oil so as to effect return of the rams and also have by-pass positions.

At the start of a cycle, both intensifiers will be in the position shown in Figure 1. At that time, the valve stem of main control valve 32 will be in position to connect the motivating fluid pressure means or to feed main high pressure oil through pipe 42 to control valve 31A, which in turn through pipe 43 is connected to low pressure cylinder USA. This will serve to start the movement of the intensifier ram upwardly and thus cause high pressure to be furnished at'the outlet of the high pressure cylinder 115A. The opposite or upper side of low pressure cylinder WA is connected through return pipe 44A, port 45A, port 46A and return line 4|, to storage tank 40.

At their lowermost position, both rams will engage their lowermost limit switch MA, 2135, respectively.

With the main control valve in the position shown in Figure l, auxiliary pump 23 will be connected through line 33, port 41 in control valve 32, and port 46 to the secondary control valve 313, controlvalve 313 being illustrated in the bypass position in Figure 1. When ram l'ZA dur ing its upward movement engages limit switch 22A (Figure 2), secondary valve 313 will be moved to. the left by solenoid 3815 so as to connect auxiliary pump 29 through port 493, port 303,, line 5lB with the lower side of cylinder |6B,, thus subjecting the idle intensifier cylinder MB to the auxiliary pump pressure or a precompression pressure. The fiuid in the high pressure cylinder in said left unit will be pre compressed until the pressure is equal to that in the operating or right intensifier unit. For a certain interval of time, the two intensifier units may be moving upwardly together, but no increase in pressure will occur because the automatic pressure control of one or both of the pumps will reduce the delivery in accordance with the pressure.

As soon as ram i2A reaches its upper position (Figure 3') wherein it contacts the upper limit switch 23A, such will serve to move the main control valve 32 to the right (Figure 3) which will disconnect the main pump 28 from the secondary control valve B'lA and will connect the main pump through valve 32, port 46, pipe 52, port 49B, port 5013, line 558 to the lower side of the left hand low pressure cylinder 1GB. Pipe 44B of the left unit will be connected through secondary control valve 31B with return line to the tank 4%.

The aforementioned movement of main control valve 32 (Figure 3) causes auxiliary pump 29 to be connected to secondary control valve 31A through line 42. After a short predetermined delay, by means of a suitable time relay valve, shown diagrammatically connected to control box 26, valve 31A will be moved to the right (Figure 4) so as to connect the auxiliary pump 29 through line 42, port 45A, line MA with the top of the right hand low pressure cylinder USA, and thus will cause movement of the right hand pressure intensifier cylinder downwardly.

When the right hand ram l2A again has reached its lower position, the lower limit switch 2 IA will be operated and place the control valve 31A in a bypass position similar to the position of valve 313 in Figure 1. At this time, one half of the cycle will have been completed.

As the left ram I2B moves upwardly, it will contact the various limit switches 22B, 2313 in a manner similar to that described for the right hand intensifier unit, so that the right hand intensifier will have precompression fluid intro duced in the low pressure cylinder ram and the cycle repeated.

As an example of one specific form which the twin intensifier unit can take, reference may be made to Figures 5 and 6 wherein base i5 has mounted thereon low pressure cylinders 15, said cylinders being fastened to the frame by bolts 11. Intermediate frame 13 connects high pressure cylinders 19 to the base 15. The high pressure cylinders may have outlet apertures 39 in the top and the low pressure cylinders may have main pressure inlets 8| near the bottom thereof with return pressure openings 82 adjacent the top thereof. The low pressure ram 83 is connected to'high pressure ram 84 in any suitable manner.

main control valve 32serves toselectively precompres'sion at the correct side of said cylinders with motivating pressure fluid means, flow control means controlling the flow of motivating fluid to said cylinders, piston stroke controlled means connected with said flow control means for the'motivating pressure cylinders to alternately energize the same, and control means connecting one of said cylinders with a precoinpression source of fluid While the other piston is moving in its pressure stroke and before it has completed its stroke and has been reversed, so that a substantially constant pressure will be delivered by said intensifiers.

2. In a pressure changing fluid motor apparatus, the combination comprising at least a pair of cylinders having pressure stroke ends and return stroke ends, a reciprocable piston in each of said cylinders, a source of motivating pressure fluid, a main switch-over control valve connected with said motivating pressure fluid means, a secondary control valve for each of said cylinders, said secondary control valves being connected to said main control valve and to the pressure stroke ends'of their respective cylinders, control means connected with said secondary control valves operated in response to movement of the first of said pistons on its pressure stroke to move one of said secondary valves to admit precompression fluid pressure to the other of said cylinders While the first piston is still on its pressure stroke, and control means connected with said switch-over valve for changing said motivating pressure fluid from one cylinder to the other.

3. In a fluid motor apparatus connected with a fluid pressure changing hydraulic means, the combination comprising at least a pair of pressure changing cylinders having pressure stroke ends and return stroke ends, a reciprocable piston in each of said cylinders, a source of motivating pressure for said cylinders, a pair of valves controlling the inlet and outlet of fluid from the pressure stroke ends of said cylinder means, and control means connected to said valves responsive to movement of said pistons at a point intermediate the ends of the strokes thereof for admitting a first precompression pressure to one of said cylinders While the piston in the other is on its pressure stroke and before motivating pressure is admitted thereto.

4. In a pressure changing fluid motor apparatus, the combination comprising at least a pair of fluid motor cylinders having pressure stroke ends and return stroke ends, a reciprocable piston in each of said cylinders, a main motivating pressure fluid means, an auxiliary pressure fluid means, control valve means connected with said 5. In a pressure changing fluid motor apparatus, the combination comprising at least a pair of fluid motor cylindershaving pressure stroke ends and return stroke ends, each of said cylinders having a reciprocable piston therein, main main motivating pressure fluid means and said auxiliary fluid means alternately With said cylinin the other cylinder has reached the end of its pressure stroke under the influence of the main motivating pressure fluid, and stroke controlled means connected to said secondary valve means connecting said auxiliary pressure 6. In a fluid motor apparatus, the combination comprising a pair of cylinders having pressure stroke and return stroke ends,

fluid source, secondary valve means for each pressure stroke end and connected therewith controlling flow of pressure fluid to and therefrom, a main switch-over valve connected to said main and auxiliary fluid pressure alternately to one of said power stroke ends before the other piston has completed its pressure stroke under influence of the ma n motivating pressure fluid. 7. In a pressure changing fluid motor apparatus, the combination comprising a pair of cylin- '3 controlling the flow of main and auxiliary pres-1 sure iiuid to each or said secondary valve means, valve operators connected to said main valve and secondary valves, piston stroke controlled limit switch means in the path of operation of each of said pistons selectively operating said valve operators for each of said valves, said switch means including a first switch for each piston connected with the main valve operator to alternate the main fluid source between said pistons, a second swch -for each piston connected to its seconda v valve means alternately connecting a ton th said auxiliary fluid source heiore the other piston has reached the end of its pressure stroke, so that the source of auxiliary pressure connected to one of said pressure stroke ends ceiore the other piston has completed its pressure stroke under influence or the main motivating pressure fluid, and means shifting auxiliary pressure to the return stroke end after the piston reaches the of its stroke.

8. In a pressure changing fluid motor apparatus, the combination comprising a pair or cylinders hav a pressure stroke and return stroke ends, a reciproca'tcle piston in each or said cylinders, a main motivating pressure fluid source, an auxiliary pressure fluid source, secondary valve means for each pressure stroke end controlling flow of pressure fluid to and therefrom, a main switch-over valve connected to said fluid sources controlling the flow or" main and auxiliary pres-- sure fluid to each or said secondary valve means, valve operators connected to said main valve and secondary valves, piston stroke controlled limit switch means in the path of operation of each of said pistons selectively operating said valve operators for each of said valves, said switch means including a first switch for each piston connected with the main valve operator to alternate the main fluid source between said pistons, a second switch for each piston connected to its respective secondary valve means alternately connecting a piston With. said auxiliary fluid source before the other piston has reached the end or its pressure stroke, so that the source of auxiliary pressure is connected to one of said inlet pressure stroke ends before the other piston has completed its pressure stroke under influence of the main motivating pressure fluid, time delay means connected with said secondary valve operators shifting the auxiliary pressure to the return stroke end of a cylinder after the piston therein. reaches the end of its pressure stroke.

FRANCIS J. KENT. REYIVIO'ND M. REICHL.

References Gited in the file of this patent UNITED STATES PATENTS

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