Patent Grant
8677799
The invention relates to an apparatus for actuating of processing machines such as forging presses, extrusion presses, forging hammers, steel working machines, milling machines or other metal forming machines.
Another object of the invention is to create a suitable application of such an apparatus.
The invention also relates to a method for metal forming machines.
Still another object is to suggest a control for such metal forming machines like forging presses or the like using an apparatus according to the invention.
Metal working machines like forging presses, forging hammers, extrusion presses, steel working machines, milling machines are well-known. DE 33 26 690 C2 describes an apparatus for actuating a hydraulic forging press with several variable flow generators of pressure. Those generators receive hydraulic fluid by a boost pump from a source via a check valve.
DE 1 502 282 describes a forging press with a hydraulic actuator and accumulators.
Also the forging press according to DE 2 223 709 works with accumulators via distribution valves.
Summarizing, some of the hydraulic machines works with High Water Based Fluids (HWBF) or even pure water. Those fluids are very aggressive and cannot be pumped by any type of pumps. The most common solution to handle those fluids is to use fixed delivery reciprocating pumps, e.g. triplex or quintuplex pumps, delivering into hydraulic accumulators which then restitute their energy to the system through proportional valves. The fact that this type of pump delivers a fixed flow prevents its use to drive directly the hydraulic cylinders of the machines which need different speeds according to the sequences of their cycles (approach phase, working phase, return phase).
The main disadvantages of those hydraulic machines with motors driven fixed delivery pumps, hydraulic accumulators, proportional valves and hydraulic cylinders are the following:
The principles of the fixed delivery reciprocating pumps are:
An electric motor shaft goes into a gearbox to reduce its rotational speed. The outlet shaft of the reduction box drives a cam shaft to transform the rotational movement into a linear movement transmitted to a certain number of cylinders (3 or 5 usually). The bodies of the cylinders hold an inlet check valve and an outlet check valve. During one complete turn of the cam shaft, the piston of the cylinder makes a backward movement admitting the pumped fluid into the cylinder from the inlet check valve and then a forward movement to deliver the fluid through the outlet check valve.
The main disadvantages of these reciprocating pumps are:
The object of the invention is to overcome these disadvantages.
One object of the invention is to offer an apparatus for actuating of processing machines, such as presses, forging presses, extrusion presses, forging hammers, steel working machines, milling machines or other metal forming machines, by means of fluid pressurizing media.
Another object of the invention is to suggest an application of an apparatus according to the invention.
Another object of the invention is to suggest a method for those metal forming machines.
Still another object of the invention is to offer a control of those metal forming machines.
Still another object of the invention is to offer a metal forming machine as described above.
The solution of the first object is described in any of claims 1 to 5, independently.
An apparatus for actuating of processing machines like metal forming machines as described above contain at least one variable delivery pump or more than one variable delivery pump, which pump via at least one distribution valve or several distribution valves the fluid, for example mineral oil, directly into the cylinder rooms of hydrostatic generators or hydrostatic actuators (rams).
The pressure of the fluid delivered by the variable pumps can be up to 500 bar, preferably up to 350 bar. The sealed pistons of the generators or actuators are each connected via separate piston rods to another piston which is movable in a separate or the same cylinder, also in a sealed manner. Separate cylinder rooms receive via different pipes or channels from a fluid or water boost supply separately a specific amount of fluid or liquid which is being compressed by the movable pistons working in opposite arranged cylinders. The circuit for this fluid or liquids like water is completely separated from a supply circuit which delivers a fluid, for example hydraulic oil, to the opposite arranged cylinder rooms of the rams. One of the pair of pistons or rams goes up, the other pair of pistons goes down and vice versa. Both generators or actuators or rams deliver fluid, especially water based fluids or pure water, into a pipe or channel system, which is connected to the metal forming machine, like a forging press or the like. The frequency or pulsation in the pressure line is very small and smooth, almost equal. There could be also more than two, for example four or even more generators or actuators or rams which work altogether and deliver liquids or fluid under high pressure to the pipe or channel to the system which leads to the metal forming machine.
The main advantages of such an apparatus or machineries are:
In one aspect of the invention, the invention may comprise an apparatus with at least two separated e.g. hydrostatic generators or pressure actuators or rams with at least one distribution valve and a motor-driven pump that is variable with regard to its flow rate.
In another aspect of the invention, the invention may comprise an apparatus for actuating processing machines with multiple motor-driven pumps, which are all variable with regard to their flow rate with at least two separated e.g. hydrostatic pressure generators or e.g. hydrostatic actuators.
In another aspect of the invention, the invention may comprise an apparatus for actuating such processing machines with a motor driven pump that is variable with regard to its flow rate and at least two separated e.g. hydrostatic pressure generators or hydrostatic actuators, wherein the pipe or channel system of the pressure pipe or channel which leads to the metal forming machine is completely separated from the pipe or channel system which is connected to the motor driven pump or pumps.
In another aspect of the invention, the invention may comprise multiple motor driven pumps which are variable with regard to their flow rate deliver hydraulic liquid, hydraulic oil, emulsion or the like and pump it into the separated or in the collective pressurizing medium pipes or channels, whereas the pressurizing medium pipe or channel coming from the variable pumps can be connected to each of the pressure generators or actuators via interconnection of distribution valves, and whereby the pressure generators or actuators deliver a different pressurizing medium in a separate pressurizing media pipe or channel system for the purpose of actuating the allocated processing machine, whereas the pressurizing medium is different from the fluid, for example, hydraulic oil, delivered by the variable pumps for actuating the pressure generators or actuators (rams).
In another aspect of the invention, the invention may comprise an apparatus for actuating of processing machines with one or multiple motor driven pumps that are variable with regard to their flow rate, which actuates at least two alternately driven pressure generators or actuators. The fluid which is delivered by the variable motor driven pumps is different from the fluid which is compressed by the generators or actuators, for example pure water or high water based fluid.
The application of an apparatus according to any of the embodiments detailed herein, or arrangements or combinations thereof, provides special advantages in connection with metal forming machines like forging presses or the like.
The foregoing and other objects and advantages of the invention will appear in the detailed description which follows. In the description, reference is made to the accompanying drawings which illustrate a preferred embodiment of the invention as examples. Many modifications and variations will be apparent to those skilled in the art. Therefore, the invention should not be limited to the embodiment described, but should be defined by the claims.
One embodiment of the invention is described, by way of example, with reference to the accompanying drawings, in which:
a-2g show step by step the movements of the cylinders during a cycle of the apparatus to bring a complete understanding of the principle:
a Step 1—Beginning of the cycle; generator is delivering pressurized fluid to the system through outlet check valve; inlet check valve is closed; generator is precompressed; the pressures are enclosed in the cylinders; piston is ready to deliver fluid to the system; check valves are closed;
b Step 2—Generator has been filled with the fluid through inlet check valve still opened; check valve is closed; generator is delivering pressurized fluid to the system through outlet check valve; inlet check valve is closed;
c Step 3—Generator is ready for precompression; check valves are closed; generator is still delivering pressurized fluid to the system through outlet check valve; inlet check valve is closed;
d Step 4—Generator is precompressed; the pressures are enclosed in the cylinders; piston is ready to deliver fluid to the system; check valves are closed; generator is delivering pressurized fluid to the system through outlet check valve; inlet check valve is closed;
e Step 5—Generator is delivering pressurized fluid to the system through outlet check valve; inlet check valve is closed; generator has been filled with the fluid through inlet check valve still opened; check valve is closed;
f Step 6—Generator is still delivering pressurized fluid to the system through outlet check valve; inlet check valve is closed; generator is ready for precompression; check valves are closed;
g Step 7—End of the cycle—Generator is delivering pressurized fluid to the system through outlet check valve; inlet check valve is closed; generator is precompressed; the pressures are enclosed in the cylinders; piston is ready to deliver fluid to the system; check valves are closed; the position is identical to the position of
In
The pistons 1a, 1b or 2a, 2b are axially movable in the directions X or Y in a sealed manner in cylinders 1c, 1d or 2c, 2d. The cylinders 1c, 1d or 2c, 2d may also be connected with each other to build one cylinder part, each of which contains the cylinders 1c, 1d or 2c, 2d.
The pistons 1a, 1b and 2a, 2b and their cylinders 1c, 1d and 2c, 2d have the same size and same diameter in the shown embodiment. But it should be clear that the pressure active surfaces of the pistons 1a, 1b and 2a, 2b may be identical or different in size.
It is also clear for one skilled in the art that the pressure active surfaces of the pistons 1b, 2b may be greater or smaller than the pressure active surfaces of the pistons 1a, 2a to get higher or lower pressures, respectively, at the pressure side of the rams 1 and 2.
It should be also clear that because of simplicity, in the drawings are shown two hydraulic generators or actuators 1, 2 (rams), but there could be also one or more than two, for example four or six or even a greater number of generators or actuators 1, 2 (rams) than shown in the drawings.
The pressure generators 1, 2 may be arranged vertically with their longitudinal axes. In the drawings these axes in which the pistons 1a, 1b and 2a, 2b can move in the direction X or Y are parallel, but there are also solutions possible, in which the cylinders may be arranged in a different position, for example horizontally or inclined to each other should this be necessary.
It is also clear for one skilled in the art that the pressure generators 1, 2 must not be close together. One or more than one generator may be arranged from the other generators in a distance, for example in a different room without changing the function which will be described in more details now.
Above piston 1a and below piston 1b are cylinder rooms 1f and 2f and above piston 2a and below piston 2b are cylinder rooms 1e and 2e.
Cylinder rooms 1f and 2f are each connected to a pipe or channel 19 and 20 which are connected to a control manifold 25 with two admission or distribution valves (21, 22) and two exhaust valves 23, 24 each actuated by a solenoid which is controlled by the automation cubicle 48. These valves 21, 22, 23 and 24 may be connected to lading manifold 27. Pipe 52 leads to a pumping station with three pumps 34, 35 and 36 which are variable with regard to their flow rate. Each pump 34, 35, 36 is motor-driven by a suitable motor, for example an electrical motor 31, 32 and 33. Each pump 34, 35, 36 may be controllable in regard of their flow rate by the automation cubicle 48. The pumps 34, 35 and 36 may be controlled in view of their flow rate separately or all together at the same time. There could be also more than three or less than three pumps, for example four pumps, all variable to their flow rates, if necessary. Preferably all pumps 34, 35 and 36 are equally build and may produce the same flow rate during a specific time limit if they got the same control input.
The pumping station is equipped with a filtration and cooling loop 40 for the fluid which is pumped by the pump 42 and delivered through the pipe 46. This fluid can be preferably a hydraulic liquid like hydraulic oil or emulsion. The filtration and cooling loop 40 contains a motor 41, a pump 42, a filter element 44 with a bypass check valve 43, and a cooling station 45. The reservoir 51 of the pumping station may contain a suitable amount of fluid, e.g. hydraulic oil.
The pressure lines or pressure pipes 37, 38, 39 of the three pumps 34, 35, 36 are interconnected to the loading manifold 27. Whereas in
The loading manifold 27 has an electrically controlled valve 28, a check valve 29 and a pressure limiter 30.
Pipe 26 leads to the suitable container or reservoir 51 to store backflow fluid from the hydrostatic generators or actuators 1 and 2.
Reference 13 is a filtered water boost supply with a filter 14 with bypass check valve 15, motor 17, which drives the pump 16 and a hydraulic fluid source 18.
Cylinder room 1e is connected via a pipe or channel 11 and an outlet check valve 3 to a pressure line or channel 47 which leads to the processing machine, for example a forging press, which has to be driven by the hydraulic generators or actuators 1 and 2. Reference 7 shows a precompression valve with a solenoid which allows to bypass the check valve 3 when operated in order to precompress the cylinder room 1e.
Cylinder room 2e is connected to a pipe or channel 12 via a check valve 4 also to pressure line 47. Reference 8 shows a precompression valve with a solenoid which allows to bypass the check valve 4 when operated in order to precompress the cylinder room 2e.
Both cylinder rooms 1e and 2e are connected via inlet check valves 5 and 6 to a pipe or channel 9 or 10, respectively, which is connected to the filtered water boost supply 13.
In the embodiment shown in the drawings the pipework or channel work system build by pressure line 47, pipes 11, 12, 9, 10 and the water boost supply 13 is separated from the pipe system or channel which is mainly build by pipes 19, 20, 26, 52.
The filtered water boost supply 13 delivers in the shown example pure water to cylinder rooms 1e and 2e alternately, whereas the pumps 34, 35 and 36 deliver a hydraulic fluid, like hydraulic oil or emulsion via admission and exhaust valves 21, 22, 23, 24 alternately to the cylinder rooms 1f and 2f of the hydrostatic pressure generators or actuators 1 and 2.
Therefore, both fluids which fill the cylinder rooms 1f and 2f and 1e and 2e can be completely different. Whereas in the cylinder rooms 1e and 2e can be pure water, the fluid which is pressed into the cylinder rooms 1f and 2f can be hydraulic oil or emulsion. The fluid, e.g. water, which fills the cylinder rooms 1e and 2e under pressure moves the pistons 1a, 1b or 2a, 2b in the direction X alternately, whereas the fluid, e.g. hydraulic liquid, which is delivered through pipes 19 and 20 into the cylinder rooms 1f and 2f drives the pistons 1a, 1b or 2a, 2b into the direction Y and actuates a processing machine, like a forging press by fluid under high pressure through pressure pipe or channel 47.
The fluid like water which is pumped by the filtered water boost supply 13 into pipes 9 and 10, respectively, could be under pressures from 1 to 15 bars, preferably 4 bar, whereas the pressures delivered by the pumps 34, 35, 36 through pipes 26, 52 could be up to 500 bar, preferably up to 350 bar.
The pressures of the fluids or liquids in pipe 47 could be up to 1400 bars, depending on the processing machine which has to be driven by the apparatus according the invention.
In
The piston or ram stroke of pistons 1a, 1b or 2a, 2b, respectively are each of one meter. The full cycle time of each ram stroke is around eight seconds, that is to say four seconds to pump, three seconds to return and 0.5 second to close the inlet check valve 5 or 6, 0.5 seconds to precompress the fluid.
The speed of the pistons 1a, 1b or 2a, 2b during their pumping and returning stroke is almost constant, with the exception for the short acceleration and deceleration periods at the beginning and at the end of the stroke, and has values respectively of about 250 mm/sec and 330 mm/sec. This is ten times less than the average speed of a triplex pump and more than fifteen times less than its maximum speed.
In the shown embodiment in
The control of the shown apparatus on return saves 0.5 seconds to allow for the natural closing of the inlet check valve 5 or 6 by its spring. There is no back flow under pressure through the inlet valve 5 or 6 and thus its overall efficiency gains when compared to the triplex pump.
The pistons 1a, 1b or 2a, 2b performs 7.5 cycles per minute in the shown embodiment. Each inlet and outlet check valve 5, 6 or 3, 4 then operates 7.5 times per minute compared with around 300 openings/closings per minute for a triplex pump check valves.
The apparatus shown in
The variable pumps 34, 35, 36 have the advantage that the required flows can be given for each function of the processing machine directly to the cylinders 1c, 1d of the pressure generators 1 or 2. In consequence the pressure generators 1 or 2 will deliver the necessary flows to control the speed of the processing machine in each of its phases (approach, working phase, return).
In comparison triplex pumps on water systems, those fixed delivery triplex pumps fill high pressure accumulators. These accumulators give their flow to the hydraulic system through proportional throttling valves to control the speeds of the actuators thus:
The vertical mounting of the generators or rams 1, 2 allows the on top mounted seals to work in the best conditions: concentricity and dirt particles at the bottom (far from the seals).
The overall efficiency of an apparatus according to the invention is better than on mechanically driven pumps (less power consumption).
An apparatus shown in
An apparatus shown in
The pressure generators 1 and 2 produce a very steady and uniform flow with just minor pulsations in the fluid pressure in the pressure pipe or channel 47. There is almost no pumping effect.
a-2g show a typical cycle of pistons 1a, 1b, 2a, 2b of the hydrostatic generators or rams 1 and 2.
In
b shows the same rams or generators 1 and 2 after three seconds starting their movement in
c is an intermediate position after 3.5 seconds starting in
d shows a position after four seconds from the position in
e is the situation after seven seconds starting from position
f shows the generators or rams after 7.5 seconds from
g is the situation after eight seconds from position 2a. Piston 1b is completely down moved in direction Y and the cylinder room 2e is precompressed by the opening of the valve 8. Piston 2b is ready to press the fluid under high pressure via a check valve 4 into the pipe 47.
The cylinder rooms if and 2f during the cycles described in connection with
From the foregoing description it is clear that rams or generators 1 and 2 move at all times in opposite directions to each other. For example, if piston 1a, 1b is moving in direction Y, at the same time piston 2a, 2b is moving in direction X and vice versa.
High pressure channel 47 leads to a loading manifold 57 via a check valve 59 to a distribution or several ways or distribution valve 63, whereas reference 58 shows a loading valve. Valve 60 and reference 58 is a pressure relief valve.
Decompression and exhaust valve 61 is connected via pipe to a pressure line 67 to return cylinders 68, 69, which act in the shown embodiment with a piston and piston rods on a main beam 73 of a forging press with main cylinder 75, main ram 74 and forging table 71. Reference 70 is a forged ingot and 76 a prefill and exhaust valve with pressure pilot supply 77. The main cylinder 75 is connected to a pressure line 66, which leads via decompression and exhaust valve 62 and decompression and return line either to suitable container or via distribution valve 63 to pipe 47 so that depending on the position of distribution valve 63 hydraulic liquid under pressure in pipe 47 acts via pressure line 66 on the main ram 74 and presses the forging tool 72 against the forged ingot 70. Instead of a forging press, shown in
While a single embodiment of the invention has been shown and described, some changes can be made, especially in view of the number of variable pumps and/or hydrostatic generators or hydrostatic actuators (rams). Therefore various changes may be made in the embodiment shown within the spirit of the invention and the scope of the claims.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/EP2009/005424 | 7/27/2009 | WO | 00 | 12/17/2010 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2010/124708 | 11/4/2010 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2745366 | Japikse | May 1956 | A |
| 3046923 | Yolin | Jul 1962 | A |
| 5158723 | Walchhutter et al. | Oct 1992 | A |
| 5499525 | Kordak et al. | Mar 1996 | A |
| 6520075 | Shinoda et al. | Feb 2003 | B1 |
| 6941783 | Yamanaka et al. | Sep 2005 | B2 |
| Number | Date | Country |
|---|---|---|
| 1 502 282 | Mar 1969 | DE |
| 2 223 709 | Dec 1973 | DE |
| 33 26 690 | Feb 1985 | DE |
| 43 45 339 | Oct 1997 | DE |
| 0 654 330 | May 1995 | EP |
| 2002-130201 | May 2002 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20110094280 A1 | Apr 2011 | US |
