DEVICE AND METHOD FOR CONTROLLED SUPPLY OF HIGH-PRESSURE FLUID

Abstract

A device for controlled supply of high-pressure fluid includes a pressure generator with an electric linear motor having a stator and a forcer to drive the high-pressure plunger in the high-pressure cylinder, and the electric linear motor(s) is (are) connected to a control unit. Associated methods for supplying high-pressure fluid to an apparatus are also disclosed.

Description

TECHNICAL FIELD

The present disclosure relates generally to the supply of high-pressure fluid with pressure generators, and more particularly to pressure generators that have a fluid intake in a high-pressure cylinder, and a high-pressure plunger that can be moved therein by a drive, and a high-pressure fluid supply to a high-pressure line, potentially with a pulsation damper therein, with a pressure sensor for a control unit for the drive, and potentially a pressure relief valve, and associated methods for supplying high-pressure fluid to an apparatus.

BACKGROUND

Devices with which high-pressure fluids of different types are obtained are of increasing importance in process engineering, in which these devices must satisfy the highest precision requirements at increasingly higher control speeds.

In particular with high fluid pressures, pressure fluctuations in the system components that may occur with pressure boosters, both for reasons arising due to the process as well as the materials, must be minimized, because these fluctuations result in changing mechanical loads to the different parts of the device, which can lead to wear and tear to the device.

With the hydraulic drive used to obtain high-pressure fluid in EP 2 610 490 B1 it is proposed that the quantities and/or pressures conveyed therewith be controlled with a pressure booster that has two plungers and a control module that has a pump powered by a adjustable servomotor.

To keep pressure drops low in high-pressure fluids when switching a pressure booster for water jet cutters that have two plungers, a bidirectional, i.e. reversible, servo drive for a hydraulic pump is proposed in EP 3 012 453 A2, which can supply power directly to the hydraulic pressure booster.

EP 3 012 075 B1 discloses a method for operating a water jet cutter with a high-pressure pump connected to a water reservoir that has numerous plungers, in which the plungers in the high-pressure pump are powered by a crankshaft, stopped by a drive with a servomotor, and then started up again. A bearing clearance at the crankshaft as well as the plunger joints and the mass forces during acceleration and deceleration when adjusting the drive can have disadvantages.

The devices from the prior art may have disadvantages with regard to their complexity, significant wear, difficulties regarding control thereof at low speeds, and an economic viability in need of improvement.

SUMMARY

An object of the present disclosure is to therefore create novel device for controlled supply of high-pressure fluid of the type described above, with which the disadvantages of the prior art are resolved.

This problem is solved with the present disclosure in that the pressure generator, or each of the cooperating pressure generators, has a dedicated electric linear motor that has a stator and a forcer functioning as the drive for the high-pressure plunger in the high-pressure cylinder, and each electric linear motor is connected to an electric control unit that comprises a power supply, a servo converter for electric linear motors, a programmable computer, and means for acquiring measurement values.

The advantages obtained with the present disclosure comprise a simple construction, economically viable operation, comprehensive control, and high control speeds of the device.

The cooperating pressure generators each have an electric linear motor with a stator and a forcer, in which the terms, “stator and forcer” do not refer to an embodiment for applying force, but instead describe the functions of parts of the motor that move in relation to one another in the device.

An electric linear motor axially aligned with a high-pressure cylinder and the plunger that moves therein has substantial functional advantages for a pressure generator.

The flow of force is in the same direction as the movement of the high-pressure plunger, without the normal conversion of rotational energy into translational energy, thus reducing the mass forces during acceleration and deceleration of the transmission components.

When a high-pressure fluid supply is connected to the high-pressure cylinder, powering the high-pressure plunger with an electric linear motor is a very economical solution for all of the different operating modes of the fluid and the conveyance thereof.

Electric linear motors have a simple construction for a direct translatory motion and direct precision control with an electric control unit.

An electric control unit that comprises an electric power supply, a servo converter for one or more electric linear motors, which can also be placed in cooperating pressure generators, a programmable computer, and means for acquiring measurement values, can coordinate the respective movements of the individual electric linear motors to the high-pressure plungers with a high level of precision.

In one embodiment of the present disclosure, in which a fluid supply is connected to the high-pressure cylinder, the forcer in the linear motor, and therefore the high-pressure plunger, can be moved at a higher speed to any position inside the high-pressure cylinder by the electric control unit, and positioned in this manner for a programmable or controlled high-pressure stroke.

In the above embodiment of the present disclosure, the device for controlled supply of high-pressure fluid can have two or more pressure generators connected to a single high-pressure line. Connecting the electric linear motor to an electric control unit allows for pressure generators to be combined in order to reduce pressure fluctuations in the high-pressure line and the need for a pulsation damper.

In another embodiment of the present disclosure, the pressure generators have two separate, opposing high-pressure cylinders with high-pressure plungers, with an electric linear motor connected to an electric control unit placed therebetween. The forcer, or the moving part of the linear motor, has fasteners or force-transferring connectors with which it can be connected to the high-pressure plunger.

The movement of the forcer in the electric linear motor advantageously results in filling one high-pressure cylinder with a fluid, and a pressurized supply of high-pressure fluid to a high-pressure line from the opposing high-pressure cylinder by the electric linear motor that is between the two cylinders.

This may also have advantages with regard to supplying high-pressure fluid with low pressure fluctuations when two or more apparatuses are connected to a high-pressure line for fluids and the electric linear motors can be activated in offset phases by an electric control unit.

To increase the forces of the high-pressure plungers in the high-pressure cylinders, the pressure generator(s) can be powered by two or more electric linear motors that are coupled to one another and controlled by an electric control unit, in which the forcers in the linear motors can be connected in parallel or in series to the high-pressure plunger to increase the translatory forces in the pressure system.

The present disclosure also relates to a method for supplying high-pressure fluid within variable parameters for the aforementioned apparatuses, e.g. water jet cutters.

Because of the general technological developments in process engineering, in particular with regard to the aforementioned apparatuses, another aim of the present disclosure is to eliminate the shortcomings in the prior methods for supplying high-pressure fluid to apparatuses within variable parameters through the use of pressure generators with high-pressure cylinders and high-pressure plungers that move therein.

This is achieved by the use of electric linear motor(s) to move the high-pressure plungers, in which the parameters of the method are regulated by an electric control unit. The control unit comprises a power source, a servo converter for the electric linear motor(s), a programmable computer that has inputs for measurement values for at least the fluid pressure and the plunger position in the high-pressure cylinder(s), and with which the servomotor is controlled.

The advantages obtained with the method according to the present disclosure essentially involve moving the high-pressure plunger directly with the electric linear motor(s), i.e. obtaining a direct translatory motion of the high-pressure plunger with the forcer or drive.

The flow of force to the high-pressure plunger is therefore obtained efficiently without converting rotational energy into linear energy, thus also resulting in a simple, durable, and compact construction of the transmission means, a high level of precision due to an improved detection of the current positions of the parts, an increased precision in controlling the movement at high speeds, and this also allows for an anchoring of impacts to the stator at high accelerations of the forcer in fractions of milliseconds.

In a preferred embodiment of the method obtained with the present disclosure, the high-pressure plunger sends a signal to the control unit when it reaches a predefined depth in the high-pressure cylinder, and the servo converter is then controlled such that the forcer in the linear motor moves the high-pressure plunger at a high speed, in particular to the starting position for a maximum pressure stroke.

With this version of the method, it is advantageously possible to reduce the time needed to fill a high-pressure cylinder in the pressure generator, and thus limit the drop in pressure in the high-pressure fluid through the use of a high-volume pulsation damper.

When two pressure generators are used, which are powered by linear motors that are synchronized using the above method, there is no need for a pulsation damper in the high-pressure line, because a quicker filling of the high-pressure cylinder followed by pressurization by the high-pressure plunger maintains the pressure in the high-pressure fluid, even when switching the conveyance direction of the pressure generator.

To supply a high-pressure fluid subject to minimal fluctuations with two or more cooperating devices, each of which has two separate and opposing high-pressure cylinders with high-pressure plungers and a linear motor therebetween that moves the high-pressure plungers, a control unit synchronizes the movements of the linear motors in the individual devices with a servo converter, and regulates an actual pressure determination in the high-pressure line and the inputs accordingly.

These embodiments are merely illustrative aspects of the innumerable aspects associated with the present disclosure and should not be deemed as limiting in any manner. These and other embodiment, aspects, features and advantages of the present disclosure will become apparent from the following detailed description when taken in conjunction with the referenced figures.

BRIEF DESCRIPTION OF FIGURES

The present disclosure shall be explained in greater detail below in reference to the schematic drawings and illustrations, which each show just one of numerous possible embodiments.

FIG. 1 shows a high-pressure pump with a pressure generator and an electric linear motor according to an embodiment of the present disclosure;

FIG. 1A shows a high-pressure curve obtained with the pump in FIG. 1;

FIG. 2 shows a high-pressure pump with a multi-phase pressure generator according to another embodiment of the present disclosure;

FIG. 2A shows the high-pressure curves obtained with the pump in FIG. 2;

FIG. 3 shows a high-pressure pump with two separate and opposing pressure generators with an electric linear motor according to another embodiment of the present disclosure;

FIG. 3A shows the high-pressure curves obtained with the pump in FIG. 3;

FIG. 4 shows a high-pressure pump with synchronized pressure generators according to another embodiment of the present disclosure;

FIG. 5 shows a high-pressure pump coupled to a linear motor according to another embodiment of the present disclosure;

FIG. 6 shows a high-pressure pump coupled longitudinally to a linear motor according to another embodiment of the present disclosure; and

FIG. 7 shows a high-pressure pump with a two-step pressure increase according to another embodiment of the present disclosure.

DETAILED DESCRIPTION

The following description of technology is merely exemplary in nature of the subject matter, manufacture and use of one or more inventions, and is not intended to limit the scope, application, or uses of any specific invention claimed in this application or in such other applications as may be filed claiming priority to this application, or patents issuing therefrom. The following definitions and non-limiting guidelines must be considered in reviewing the description of the technology set forth herein.

In the following detailed description numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it will be understood by those skilled in the art that the present disclosure may be practiced without these specific details. For example, the present disclosure is not limited in scope to the particular type of industry application depicted in the figures. In other instances, well-known methods, procedures, and components have not been described in detail so as not to obscure the present disclosure.

The headings and sub-headings used herein are intended only for general organization of topics within the present disclosure and are not intended to limit the disclosure of the technology or any aspect thereof. In particular, subject matter disclosed in the “Background” may include novel technology and may not constitute a recitation of prior art. Subject matter disclosed in the “Summary” is not an exhaustive or complete disclosure of the entire scope of the technology or any embodiments thereof. Classification or discussion of a material within a section of this specification as having a particular utility is made for convenience, and no inference should be drawn that the material must necessarily or solely function in accordance with its classification herein when it is used in any given composition.

The citation of references herein does not constitute an admission that those references are prior art or have any relevance to the patentability of the technology disclosed herein. All references cited in the “Detailed Description” section of this specification are hereby incorporated by reference in their entirety.

The following list of reference symbols is intended to simplify identification of the parts and components in the schematic drawings and illustrations:

• • D, D′, D″, D′″ pressure generator
  • L, L′, L″ electric linear motor
  • p₁, p₂ generator pressure
  • [p] pressure in high-pressure fluid
  • [t] time
  • 1 fluid intake
  • 2 check valve
  • 3 pressure regulator
  • 4 booster pump
  • 5 filter unit
  • 6 baseplate
  • 7 guide rail
  • 8 guide carriage
  • 9 stator
  • 10 forcer
  • 11 control line
  • 12 electric control unit
  • 13 suction valve
  • 14 pressure valve
  • 15 high-pressure cylinder
  • 16 connecting flange
  • 17 high-pressure plunger
  • 18 plunger fastener
  • 19 connecting plate
  • 20 pulsation damper
  • 21 pressure sensor
  • 22 high-pressure connection
  • 23 pressure release valve
  • 24 bleed-off connection

FIG. 1 shows a high-pressure pump that has a fluid intake 1, a pressure generator D, an electric linear motor L, and a high-pressure connection 22.

Although the high-pressure pumps shown in the drawings (FIG. 1 to FIG. 7) can also be advantageously used as high-pressure pumps for water jet cutters, the fluid supply is depicted schematically as a conventional water supply.

Therein, 2 indicates a check valve for the fluid, 3 indicates a pressure regulator (if necessary), 4 indicates a booster pump for quickly filling the high-pressure cylinder 15 in the pressure generator D, 5 indicates a filter for cleaning the fluid, and 13 indicates a return suction valve.

It is also expressly held that the high-pressure pumps can be used effectively with all types of fluids.

According to FIG. 1, a pressure generator D that has a high-pressure cylinder 15 and a high-pressure plunger 17 is attached to a baseplate 6 with a connecting flange 16. The high-pressure plunger 17 is moved in the axial direction by a forcer 10 in an electric linear motor L connected thereto by a plunger fastener 18, and a stator 9 is connected to the baseplate 6.

The terms, “forcer,” and “stator,” refer to the moving part and stationary part in the present description of an electric linear motor, regardless of the specific form of each part. It is also possible for the stator to be the moving part and the forcer to be the stationary part.

The electric linear motor L is connected to an electric control unit 12, which comprises at least one electric power supply, a servo converter for the electric linear motor L, a programmable computer, and a means for acquiring measurement values.

An electric control unit 12 controls the direction in which the forcer moves and a direct force applied to the high-pressure plunger 17 in a high-pressure cylinder 15 in a pressure generator D, for which there is also a return suction valve 13 in the fluid intake and another check valve 14 for conveying high-pressure fluid.

A pulsation damper 20 is used to keep fluctuations to a minimum at the connection 22 for high-pressure fluids.

A pressure sensor 21 sends fluid pressure measurements to the control unit 12, which can be used to regulate the movement of the linear motor.

A pressure relief valve 23 with a bleed-off connection 24 can be incorporated in the high-pressure fluid line 20.

FIG. 1A shows a graph of the pressure [p] in the high-pressure line 22 in the device shown in FIG. 1, plotted over time [t].

The high-pressure plunger 17 is pushed into the high-pressure cylinder 15 by a movement of the forcer 10 in the electric linear motor L controlled by the control unit 12, in which the fluid pressure [p] in the high-pressure line 20 increases to a predefined pressure p₁ in the regions indicated by a.

Following a phase b in which fluid is conveyed, the high-pressure plunger 17 is retracted by the forcer 10 in the electric linear motor L, in which this return movement can take place quickly, at a speed controlled by the electric control unit 12.

The pressure valve 14 closes, and the fluid pressure in the pump system decreases at g to the ambient pressure, as shown in FIG. 1A. High-pressure fluid is then resupplied to the system by a pulsation damper 20 in the high-pressure line, such that a pressure drop p₂ is delayed at d.

When the high-pressure plunger 17 reaches the starting position in the high-pressure cylinder 15, the forcer 10 begins another pressure phase with which the pressure drop p₂ at the din the graph is reversed and the predefined conveyance pressure p₁ is restored.

FIG. 2 shows a high-pressure pump with a multi-phase pressure generator D, i.e. that is operated in phases.

The individual pressure generators D, D′, D″ are identical to that shown in FIG. 1, and their dedicated electric linear motors L, L′, L″ are connected to a control unit 12 that regulates the movements of the high-pressure plungers 17, 17′, 17″ over time. This coordinates the conveyance of fluid to the high-pressure line 20 such that pressure fluctuation is minimized, as shown in FIG. 2A.

FIG. 3 shows a schematic illustration of a high-pressure pump that has two opposing pressure generators D and D′ on either side of an electric linear motor. This configuration of pressure generators D, D′ is known per se, but by placing an electric linear motor L with a control unit 12 between them, decisive advantages are obtained with regard to the system and the process that also solve economic problems in the prior art.

In detail, the forcer 10 in an electric linear motor L is connected by plunger fasteners 18, 18′ to the respective opposing high-pressure plungers 17, 17′ in the two high-pressure cylinders 15, 15′ in the pressure generators D, D′ to obtain a very advantageous, compact, light unit without play.

When high-pressure fluid is obtained through a connection 22, the electric control unit 12 directly controls the functioning of the electric linear motor L. A linear movement of the forcer 10 in one direction results in fluid being conveyed by a pressure generator D, while the high-pressure cylinder 17′ in the other pressure generator D′ is simultaneously filled.

FIG. 3A shows the pressure [p] over time [t] in the high-pressure pump in FIG. 3 when in operation.

A substantially constant conveyance pressure Pi with limited pressure drops is obtained in the high-pressure fluid by the two alternating high-pressure cylinders 15, 15′ through an alternating action of the two pressure generators D, D′.

FIG. 4 shows a schematic illustration of a high-pressure pump with synchronized pressure generators.

This type of fluid-conveying device, which displays the lowest pressure fluctuations at the high-pressure connection 22, contains four synchronized pressure generators D, D′, D″, D′″, D″″, which form two devices, each of which has two opposing pressure generators.

With the high-pressure pump shown in FIG. 4, the electric linear motors L, L′ are controlled synchronously by the electric control unit 12 such that at least one pressure generator D conveys high-pressure fluid at any given time under the conditions determined by the electric control unit 12.

The pressure forces acting on the high-pressure cylinder 17 by the pressure generator D through the electric linear motors coupled thereto shall be explained in greater detail below in reference to the schematic illustrations in the drawings.

FIG. 5 shows a high-pressure pump that has two opposing pressure generators D, D′, in which parallel electric linear motors L are placed between the hydraulic pressure generators D, D′, in order to increase the translatory forces.

FIG. 6 shows a schematic illustration of a serial configuration of electric linear motors L, L′ between the hydraulic pressure generators D, D′.

A high-pressure pump is shown in FIG. 7 in which the pressure increase is doubled by two pumps powered by electric linear motors L, L′. The first pressure increase in the fluid from the pressure at the intake 1 to a high-pressure range is obtained with a first linear motor pump system. The pressure in the high-pressure fluid is then further increased by a second linear motor pump system. The control unit 12 controls and coordinates the two electric linear motors L, L′ for the two pumps.

Exemplary embodiments of the disclosure have been described above to explain the principles of the present disclosure and its practical application to thereby enable others skilled in the art to utilize the present disclosure. However, as various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the present disclosure, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings, including all materials expressly incorporated by reference herein, shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present disclosure should not be limited by the above-described exemplary embodiment but should be defined only in accordance with the following claims appended hereto and their equivalents.

Claims

1. A device for controlled supply of high-pressure fluid by means of at least one pressure generator that has a fluid supply and a fluid intake in a high-pressure cylinder, which has a high-pressure plunger that can be moved therein by a drive, with which a high-pressure fluid is supplied to a high-pressure line, which may contain a pulsation damper, which has a pressure sensor for controlling the drive, and possibly contains a pressure release valve that can be opened and closed, wherein the at least one pressure generator has comprises an electric linear motor with a stator and a forcer for operating the high-pressure plunger in the high-pressure cylinder, and the electric linear motor is connected with an control unit comprising an electrical power supply, a servo converter for the electric linear a programmable computer, and at least one sensor.

2. The device according to claim 1, wherein the pressure generator further comprises a high-pressure cylinder, and wherein the high-pressure plunger is configured for movement by the electric linear motor from any position in the high-pressure cylinder, which has a fluid intake connected thereto, such that it can be positioned for a programmed and controllable high-pressure stroke.

3. The device according to claim 2, further comprising at least a second pressure generator having a second electric linear motor, wherein the at least two pressure generators are each connected to the high-pressure line, and both electric linear motors are connected to the electrical control unit for coordinated operation.

4. The device according to claim 1, wherein the pressure generator further comprises two separate, opposing high-pressure cylinders with high-pressure plungers, and wherein the electric linear motor is connected between these high-pressure cylinders, and force-transferring connections or plunger fasteners are connected to the forcer in the electric linear motor at opposing ends thereof in order to move the force-transferring connections or plunger fasteners.

5. The device according to claim 4, wherein two apparatuses are connected to the high-pressure fluid line and the electric linear motors can be powered by the control unit in offset phases.

6. The device according to claim 1, further comprising at least a second pressure generator having a second electric linear motors and wherein both electric linear motors are regulated by the control unit.

7. A method for supplying high-pressure fluid within variable parameters to an apparatus through the use of pressure generators that have a high-pressure cylinder and a high-pressure plunger that moves therein, characterized in that the high-pressure cylinder is moved by an electric linear motor, wherein the method parameters are regulated by an control unit, which control unit comprises a power supply, a servo converter for the electric linear motor, and a programmable computer having measurement inputs for at least a fluid pressure and a position of the high-pressure plunger in the high-pressure cylinder and configured to control the servo converter.

8. The method according to claim 7, characterized in that the high-pressure plunger sends a signal to the control unit when high-pressure plunger reaches a specified position in the high-pressure cylinder, and the servo converter is regulated such that the forcer in the electric liner motor moves the high-pressure plunger at a high speed to a new position in the high-pressure cylinder, in particular a starting position for a maximum compression stroke.

9. The method according to claim 8, wherein two or more pressure generators feed into a high-pressure fluid line, under the condition that the control unit operates the electric linear motors in different phases with the servo converter, i.e. following a pressure phase or conveyance phase in a first pressure generator, while at least one other pressure generator conveys high-pressure fluid, the high-pressure cylinder is filled and pressure is built up in the fluid in the first pressure generator such that at the end of the pressure phase in the other pressure generators, the first pressure generator conveys fluid, and a pressure drop in the high-pressure fluid line is prevented.

10. The method according to claim 7, wherein two or more devices are formed that have separate, opposing high-pressure cylinders with high-pressure plungers, and there are linear motors therebetween, which move the high-pressure plungers under the condition that control unit the control unit synchronizes the linear motor movements in the individual devices with a servo converter and regulates them in accordance with an actual pressure reading in the high-pressure fluid and the pressure specifications.