System and method for delivering hydraulic liquid

Abstract

A system and method delivering hydraulic liquid at different predetermined and controllable pressures for a hydraulic tool or machine is disclosed. The system comprises an electric motor (100) comprising a rotor (110) and a stator (120); a pump (200), the pump being a plunger-type pump and comprising a cam (210), a cam shaft (220), a plunger (230), a plunger chamber (240), and a valve (250), the valve (250) opening or closing an inlet (260) for the hydraulic liquid to the plunger chamber (240), the plunger chamber (240) comprising an outlet (270) for the hydraulic liquid, the plunger (230) engaging the cam (210), and the cam shaft (220) being connected to the rotor (110); a pressure sensor (290) sensing pressure of the hydraulic liquid to be delivered; and a controller (300) configured to control the opening and closing of the valve (250) in relation to pressure sensed by the pressure sensor (300) and rotational position of the rotor (110) or cam (210), the controller (300) thereby controlling the volume and pressure of the hydraulic liquid to the outlet (270) and the load on the electric motor (100).

Description

Technical Field

[0001] The present disclosure relates to a pump delivering high pressure hydraulic liquid. More particularly, the present disclosure relates to a system and a method for delivering hydraulic liquid at different predetermined and controllable pressures for a hydraulic tool or machine; a system for controlling a pump to deliver hydraulic liquid for a hydraulic tool or machine at different controllable pressures and flows, and a method using such a system; and a system delivering hydraulic liquid for a hydraulic tool or machine at different controllable pressures and flows.Background

[0002] Pumps delivering a high pressure of hydraulic liquid are expensive, heavy, noisy, and cumbersome to use. High pressure may be a few hundred bars, for example 500 bars, 50 MPa, and upwards. The present high-pressure pumps are two-stage positive displacement pumps where a first pump increases the pressure, and a second pump further increases the pressure to a higher pressure. The second pump is made to high specifications and is expensive to produce and maintain. It is desirable to have a high-pressure pump, for delivering hydraulic liquid, that is inexpensive to manufacture, light, silent, and easy to use.

[0003] Existing high-pressure pumps delivers hydraulic liquid at only one fixed specific flow. Existing pumps can only be set manually to deliver the hydraulic liquid at different pressures. It is desirable to have a pump that can produce different predetermined pressures and flows, preferably over time, delivering demand controlled hydraulic power. It is desirable to have a pump that can produce different flows. It is desirable to have a pump that can be controlled in an easy and programmable way.

[0004] It is desirable to be able to give specific tools or machines a specific demand controlled delivery profile of hydraulic liquid. For example, a pump providing a first pressure at a first flow and subsequently a smooth transition to a second pressure at a second flow. This is not possible with existing high-pressure pumps.

[0005] A further technical problem is that any pump must fit and work together with already existing tools and machines. It is desirable that any solution is simple, not expensive to produce, is reliable, and safe to use. It is further a technical problem to avoid cumbersome arrangements that are time consuming or expensive to manufacture or assemble.Summary of the Invention

[0006] It is an object of the present invention to provide a system and a method for delivering hydraulic liquid at different predetermined and controllable pressures for a hydraulic tool or machine. This object can be achieved by the features as defined by the independent claims. Further enhancements are characterized by the dependent claims. The invention is defined by the claims.

[0007] According to one embodiment, a system delivering hydraulic liquid at different predetermined and controllable pressures for a hydraulic tool or machine is disclosed. The system comprises an electric motor 100 comprising a rotor 110 and a stator 120; a pump 200, the pump being a plunger-type pump and comprising a cam 210, a cam shaft 220, a plunger 230, a plunger chamber 240, and a valve 250, the valve 250 opening or closing an inlet 260 for the hydraulic liquid to the plunger chamber 240, the plunger chamber 240 comprising an outlet 270 for the hydraulic liquid, the plunger 230 engaging the cam 210, and the cam shaft 220 being connected to the rotor 110; a pressure sensor 290 sensing pressure of the hydraulic liquid to be delivered; and a controller 300 configured to control the opening and closing of the valve 250 in relation to pressure sensed by the pressure sensor 300 and rotational position of the rotor 110 or cam 210, the controller 300 thereby controlling the volume and pressure of the hydraulic liquid to the outlet 270 and the load on the electric motor 100.

[0008] According to one embodiment, the controller may be further configured to control the load on the electric motor to be substantially constant by adjusting when to open and close the valve 250 in relation to the rotational position of the rotor 110 or the cam 210 and the pressure sensed by the pressure sensor 290. The controller 300 may be further configured to control the opening or closing of the valve 250 in relation to rotational position of the rotor 110 or cam 210 to provide at least two predetermined pressures of 1500 bar and 2500 bar of the hydraulic liquid to the outlet 270.

[0009] According to one embodiment, a method for providing hydraulic liquid at different predetermined and controllable pressures, comprising providing a system according to any one of the embodiments disclosed herein. The method comprises rotating 610 the electric motor 100; sensing 620 pressure of the hydraulic liquid to be delivered; and controlling 630 the opening and closing of the valve 250 in relation to pressure sensed by the pressure sensor 290 and rotational position of the rotor 110 or cam 210, the controller 300 thereby controlling the volume and pressure of the hydraulic liquid to the outlet 270 and the load on the electric motor 100. The method may further comprise controlling 640 the load on the electric motor 100 to be substantially constant by adjusting when to open and close the valve 250 in relation to the rotational position of the rotor 110 or the cam 210 and the pressure sensed by the pressure sensor 290. The method may further comprise controlling 650 the opening or closing of the valve 250 in relation to rotational position of the rotor 110 or cam 210 to provide at least two predetermined pressures of 150 MPa, 1500 bar, and 250 MPa, 2500 bar, of the hydraulic liquid to the outlet 270.

[0010] According to at least one embodiment, a system and / or a method provides a high-pressure pump, for delivering hydraulic liquid, that is inexpensive to manufacture, light, silent, and easy to use. According to at least one embodiment the pump may produce different predetermined pressures, different flows, and may be controlled in an easy and programmable way. According to at least one embodiment the pump may give specific tools or machines a specific delivery profile of hydraulic liquid.

[0011] At least one embodiment may work together with already existing nipples, couplings, tools and / or machines. At least one embodiment avoids cumbersome arrangements that are expensive to manufacture or difficult or time consuming to assemble.

[0012] At least one of the embodiments provides one or more solutions to the problems and disadvantages with the background. Other technical advantages of the present disclosure will be readily apparent to one skilled in the art from the following description and claims. Various embodiments of the present application obtain only a subset of the advantages set forth. No one advantage is critical to the embodiments. Any claimed embodiment may be technically combined with any other claimed embodiment or embodiments.Brief Description of the Drawings

[0013] The accompanying drawings illustrate presently exemplary embodiments of the disclosure and serve to explain, by way of example, the principles of the disclosure. Fig 1 is a diagrammatic illustration of an exemplary embodiment of the disclosure; Fig 2 is a diagrammatic illustration of the exemplary embodiment of figure 1; and Fig 3 and 4 are diagrammatic illustrations of methods according to exemplary embodiments of the disclosure. Detailed Description

[0014] Figures 1 and 2 show a preferred embodiment of a system of a motor 100 and a pump 200 schematically connected to a tool 450 and a tank 400. Figure 1 is a cut through view along an axis of a cam shaft 220 and an axis of a plunger 230. Figure 2 is a cut through view along an axis of the plunger 230 and perpendicular to the view in figure 1. Fig 3 is a flow diagram of a diagrammatic illustration of a method according to an exemplary embodiment of the disclosure. Fig 4 is a flow diagram of a diagrammatic illustration of a method according to an exemplary embodiment of the disclosure.

[0015] The pump is configured to deliver hydraulic liquid at a predetermined high pressure to a hydraulic tool or machine 450. High pressure may be any pressure over 500 bar, 50 MPa, and upwards, but the pump is not limited hereto. The high pressure may be 30 MPa and upwards, or 25 MPa and upwards. A high pressure range for the system may be 30 to 300 MPa. A preferred high pressure is 1500 bar, 150 MPa. Another preferred high pressure is 2500 bar, 250 MPa. At least one embodiment may be able to selectively provide hydraulic liquid at 150 MPa and 250 MPa, and at any high pressure selected therebetween by a user of the pump. Preferably the pump should be able to selectively provide hydraulic liquid at any high pressure selected by a user of the pump. Flow as mentioned herein may be the volume of the hydraulic liquid that flows through a passage of any given section during a unit of time. At least one embodiment may be able to provide a predetermined delivery profile of hydraulic liquid. A delivery profile is a variation of flow and pressure over time, for example a high flow and low pressure in the beginning followed by a lower flow and high pressure. The delivery profile comprises at least a predetermined pressure and flow relationship, over time, of the hydraulic liquid to be deliver. At least one pump described herein can provide such a predetermined delivery profile to a tool or machine.

[0016] One embodiment discloses a system delivering hydraulic liquid at different predetermined and controllable pressures for a hydraulic tool or a hydraulic machine 450. This may include delivering hydraulic liquid at different predetermined and controllable volume and / or flows for a hydraulic tool or machine. The system comprises an electric motor 100, a pump 200, a pressure sensor 290, and a controller 300. The motor may be a frameless electric motor. The electric motor 100 comprises a rotor 110 and a stator 120. The pump 200 is a plunger-type pump and comprises a cam 210, a cam shaft 220, a plunger 230, a plunger chamber 240, and a valve 250. The valve 250 opens or closes an inlet 260 for the hydraulic liquid to the plunger chamber 240. The plunger chamber 240 comprises an outlet 270 for the hydraulic liquid. The plunger 230 engages the cam 210. The plunger 230 may engage directly or indirectly the cam 210. Preferably the plunger 230 is directly spring loaded against the cam 210. The cam shaft 220 is connected to the rotor 110. Preferably the cam shaft 220 is directly attached to the rotor 110. For example the cam shaft 220 may support the rotor 110. The rotor 110 and the stator 120 may be mounted directly onto the pump 200. For example, the rotor 110 may be directly attached to the cam shaft 220. This provides increased power density, improved efficiency, and reduced weight and size. The pressure sensor 290 senses pressure of the hydraulic liquid to be delivered. The pressure sensor 290 is preferably down streams in the outlet 270, preferably after a check valve 280.

[0017] The controller 300 is configured to control the opening and closing of the valve 250 in relation to pressure sensed by the pressure sensor 300 and rotational position of the rotor 110 or cam 210. The controller 300 thereby controls the volume and pressure of the hydraulic liquid to the outlet 270 and the load on the electric motor 100. The controller 300 may control the load on the electric motor, for example to ensure that the motor runs efficiently or is not overloaded. At the same time the controller 300 may control the volume and pressure, for example flow and pressure, of the hydraulic liquid to the outlet 270. In this way the system may provide pressurised hydraulic liquid to a tool or machine in a controlled way by controlling when to open and close of the valve 250. The controller may also control the rotation per minute, rpm, of the electric motor 100. A very power effective system capable of delivering high pressures, for example over 250 MPa, may be provided by the controller controlling the rpm and when to open and close of the valve 250.

[0018] According to one embodiment, the controller 300 may be further configured to control the load on the electric motor 100 to be substantially constant by adjusting when to open and close the valve 250 in relation to the rotational position of the rotor 110 or the cam 210 and the pressure sensed by the pressure sensor 290. In addition the controller 300 may be further configured to control the rpm of the electric motor 100 to control the load on the electric motor to be substantially constant. The controller 300 may control the load, the work, that the electric motor 100 has to produce for a predetermined pressure by controlling when to open and close the valve 250 in relation to the rotational position of the rotor 110 or the cam 210. In this way a certain pressure, flow, of hydraulic liquid may be delivered at a controlled load on the electric motor 100 driving the pump 200.

[0019] According to one embodiment, the controller 300 may be further configured to control the opening or closing of the valve 250 in relation to rotational position of the rotor 110 or cam 210 to provide at least two predetermined pressures of 1500 bar and 2500 bar of the hydraulic liquid to the outlet 270. The controller may control when the valve 250 opens or closes in relation to rotational position of the rotor 110 or cam 210, In this way more or less hydraulic liquid may be compressed by the plunger 230 in the plunger chamber 240 and exiting the outlet 270. The controller may be configured such that preset pressures of 150 MPa, 1500 bar, and 250 MPA, 2500 bar, may be selected by a user and the one and the same system delivers the selected pressure of hydraulic liquid to a tool or machine. According to one embodiment, the controller 300 may be further configured to control the opening or closing of the valve 250 in relation to rotational position of the rotor 110 or cam 210 to provide at plurality of predetermined pressures in the range of 25 MPa to 350 MPa of the hydraulic liquid to the outlet 270.

[0020] According to one embodiment, the cam shaft 220 may be connected directly to the rotor 110. The electric motor 100 may be a frameless electric motor. The cam shaft 220 may extend so that the rotor rotates around the cam shaft 220. By having the cam shaft 220 connected directly to the rotor 110, the system with the electric motor 100 and the pump 200 becomes very rigid and compact. The system may comprise one or more bearings for the cam shaft 220 only at a distal part of the cam shaft 220 away from the rotor 110. There need not to be a bearing between the cam shaft 220 and the electric motor 100. There may be only one bearing 222 between the cam shaft 220 and the pump housing, preferably at the distal end of the cam shaft 220 away from the rotor 110.

[0021] According to one embodiment, the system may further comprise a temperature sensor 150 for sensing temperature of the electric motor 100. The controller 300 may be further configured to detect the temperature of the electric motor 100 and configured to control the opening and closing of the valve 250 in relation to the temperature. The temperature sensor may be connected for electronic data transfer to the controller 300. This allows, for example, the controller 300 to ensure that the electric motor 100 does not overheat and runs efficiently.

[0022] According to one embodiment, the system may further comprise at least one sensor 130, 140, for example a hall sensor, for sensing rotational position of the rotor 110. The sensor may be connected for electronic data transfer to the controller 300, preferably only to one part of the sensor 130, 140, for example the hall sensor. The controller 300 may be further configured to detect the rotational position of the rotor 110, and thereby the position of the plunger 230, via the sensor 130. The cam shaft 220 may be directly connected to the rotor 110 and the rotor 110 may comprise one part of the sensor 130, 140, for example a permanent magnet. The housing of the electric motor 100 or the pump 200 may comprise the other part of the sensor 130, 140, for example a hall sensor. In this way the controller 300 may detect where the plunger 230 is in the plunger chamber 240 and may control opening and closing of the valve 250 accordingly. The system may comprise at least two sensors 130, 140, on the rotor 110, cam shaft 220, or cam 210. One sensor 130 may be for detecting the lowest position of the plunger 230 and one sensor may be for detecting the highest position of the plunger 230. This allows for accurate opening and closing of the valve 250 in relation to the plunger 230, which in turn provides good delivery of hydraulic liquid at different predetermined and controllable pressures for a hydraulic tool or machine.

[0023] According to one embodiment, the system may comprise a battery pack 160 for providing the controller 300 and the electric motor 100 with electric power. The controller 300 may be further configured for reducing electric power consumption of the electric motor 100 by controlling the opening and closing of the valve 250 in relation to rotational position of the rotor 110 or cam 210 and pressure sensed by the pressure sensor 300, and by controlling rotational speed, rpm, of the electric motor 100. This may allow the system to be run on the electricity provided by the battery pack 160 instead of an electric power cable to a wall socket. This allows the system to be portable, hand portable, and because the system is as described herein it is not heavy and can be carried by an operator.

[0024] According to one embodiment, the system may further comprise a control valve 420 in fluid communication with the outlet 270; a tank 400 for the hydraulic fluid; a first flow line 425 for delivering the hydraulic fluid from the control valve 420 to the tank 400; and a second flow line 430 for delivering the hydraulic fluid from the tank 400 to the pump 200. The system may also comprise a delivery flow line 410 for delivering the pressurized hydraulic fluid to a hydraulic tool or machine 450. The control valve 420, for example a solenoid valve 420, may be in fluid communication with the outlet 270. The control valve 420 may be connected for data transfer to the controller 300 and may be controlled to be opened or closed by the controller 300. The controller 300 may open or close the control valve 420 depending on the pressure sensed by the pressure sensor 290. The control valve 420 may be arranged in fluid communication between the check valve 280 and the connector 440, preferably between the pressure sensor 290 and the connector 440. The control valve 290 may open to the tank 400 via the hose 425. The tank 400 may comprise non-pressurised hydraulic liquid for the system. The tank 400 may supply hydraulic liquid to the pump 200 via the hose 430 to the valve 250 to the inlet 260 of the plunger chamber 240. A feeder pump may move the hydraulic liquid from the tank 400 to the pump via hose 430. The feeder pump may not pressurise the hydraulic liquid. The hydraulic liquid may be fed to the circular flow line 254. The hydraulic liquid may also be returned to the tank 400. The system may comprise the electric motor 100, the pump 200, the controller 300, the tank 400, the control valve 420, the two flow lines 425, 430. Such a system, as described in any embodiments herein, allows connection to a tool or machine with a hose 410 for supplying pressurised hydraulic liquid.

[0025] According to one embodiment, the plunger 230, the plunger chamber 240, and the cam 210 of the plunger-type pump are not submerged wetted piston elements. Instead, the tank 400 may provide the hydraulic liquid to the valve 250. A feed pump may be used to feed the hydraulic liquid from the tank 400 to the pump 200. The hydraulic liquid may only enter the plunger chamber when the valve 250 opens.

[0026] According to one embodiment, the controller 300 may be further configured to deliver a predetermined flow deliver profile of the hydraulic pressure to the outlet 270. The delivery profile may comprise at least a predetermined pressure and flow relationship of the delivered hydraulic liquid. The delivery profile may comprise at least a predetermined pressure and flow relationship of the delivered hydraulic liquid over time. The delivery profile may be a delivery profile as described herein.

[0027] According to one embodiment the system may further comprise a quick connect coupling 440 for connecting a hose 410 from the pump 100 to a tool or machine 450. The hose may be a hose suitable for high pressure hydraulic liquid and comprise a quick connect coupling at each end of the hose. The hose may be any one of the flow lines 410, 425, and 430 as described herein.

[0028] The system may further comprise a connector 440, for example a coupling 440 such as a quick connect coupling, in fluid connection with the outlet 270. The coupling 440 may be configured for at least a first predetermined pressure, the first predetermined pressure being lower than a second predetermined pressure. For example, the first predetermined pressure may be 150 MPa and the second predetermined pressure may be 250 MPa. The connector 440, the coupling 440, may comprise a front part 442 and a back part 444, the back part 444 may be attached to the pump 200 and the front part 442 may be connectable to another connector, for example a nipple attached to a hose 410. The back part 444 being configured for the second predetermined pressure, and the front part 442 being configured for the first predetermined pressure. This may allow tools for a lower pressure, for example 150 MPa, to be connected to the pump, even if the pump could produce a high pressure, for example 250 MPa, that is too high for such tools. Since the back part 444 may be configured for the higher pressure, this example enables safe back pressure up to 250 MPa. The connector 440 may be a coupling 440, such as a quick connect coupling.

[0029] According to one embodiment, a method for providing hydraulic liquid at different predetermined and controllable pressures is disclosed. The method comprises providing a system according to any one of the embodiments described herein. The method may use the system according to any one of the embodiments described herein. The method comprises rotating 610 the electric motor 100; sensing 620 pressure of the hydraulic liquid to be delivered; and controlling 630 the opening and closing of the valve 250 in relation to pressure sensed by the pressure sensor 290 and rotational position of the rotor 110 or cam 210. The controller 300 may thereby control the volume and pressure of the hydraulic liquid to the outlet 270 and the load on the electric motor 100. The electric motor 100 may be rotating and the valve 250 may be in an open position to allow the system to be idle and not provide any pressurised hydraulic liquid. The system may in this way be ready for providing pressurised hydraulic liquid. For example, if the tool or machine 450 is not used for the moment, then the electric motor 100 may be running and the valve 250 may be open since the pressure sensor 290 senses, and the controller 300 knows, that the predetermined pressure has been achieved and no further pressurised hydraulic liquid is needed. When the pressure sensor 290 senses that the pressure goes under the predetermined pressure, then the controller 300 may control the valve 250 to close in relation to the position of the plunger 230 in the plunger chamber 240 to start building up pressure again to the outlet 270.

[0030] According to one embodiment, the method may further comprise controlling 640 the load on the electric motor 100 to be substantially constant by adjusting when to open and close the valve 250 in relation to the rotational position of the rotor 110 or the cam 210 and the pressure sensed by the pressure sensor 290. This is also described elsewhere and may allow the system to run cost and energy efficient.

[0031] According to one embodiment, the method may further comprise controlling 650 the opening or closing of the valve 250 in relation to rotational position of the rotor 110 or cam 210 to provide at least two predetermined pressures of 150 MPa, 1500 bar, and 250 MPa, 2500 bar, of the hydraulic liquid to the outlet 270. The controller 300 may have the two predetermined pressures set and may allow for a plurality of predetermined pressures to be pre-set or to be set at any time by a user of the system. This allows one and the same pump to deliver hydraulic liquid at a variety of different pressures and may easily be changed while using the system.

[0032] According to one embodiment, the method may further comprise detecting 660 the temperature of the electric motor 100 and controlling the opening and closing of the valve 250 in relation to the temperature. According to one embodiment, the method may further comprise detecting 670 rotational position of the rotor 110, and thereby the position of the plunger 230. These embodiments are further described elsewhere herein.

[0033] According to an embodiment, a system for controlling a pump to deliver hydraulic liquid for a hydraulic tool or machine at different controllable pressures and flows is disclosed. The range may be 30 to 300 MPa. The system may provide pressurised hydraulic liquid at a predetermined pressure, preferably in the range of 30 to 300 MPa. The system comprises an electric motor 100, a pump 200, a pressure sensor 290, and a controller 300.

[0034] The electric motor 100 comprises a rotor 110 and a stator 120. The electric motor may be a frameless motor.

[0035] The pump 200 is a plunger-type pump and comprises a cam 210, a cam shaft 220, a plunger 230, a plunger chamber 240, and a valve 250. The valve 250 opens and closes an inlet 260 for the hydraulic liquid to the plunger chamber 240. The plunger chamber comprises an outlet 270 for the hydraulic liquid. The plunger 230 engages the cam 210, and the cam shaft 220 is connected to the rotor 110. For example the cam shaft 220 may support the rotor 110. In this way rotation of the electric motor 100 causes the plunger 230 to move up and down, with reference to figures 1 and 2, in the plunger chamber 240.

[0036] The pressure sensor 290 senses pressure of the hydraulic liquid to be delivered. The pressure sensor 290 may be arranged in the outlet 270. The pressure sensor 290 may be connected to the controller 300 for data transfer. The pressure sensor 290 senses the built up pressure on the other side of the check valve 280, that is the pressure of hydraulic liquid to be delivered to a tool or machine 450.

[0037] The controller 300 comprises a processor 310. The processor 310 is configured to control the opening and closing of the valve 250 in relation to pressure sensed by the pressure sensor 290 and rotational position of the rotor 110 or cam 210, and optionally as described herein. The processor 310 is configured to control the rotational speed, rpm, of the motor 100.

[0038] The processor 310 is further configured to be programmable to set a delivery profile setting the duration of the valve 250 being closed and opened and the timing when to open or close of the valve 250 in relation to the rotation position of the rotor 110 or cam 210, the delivery profile comprising at least a predetermined pressure and flow relationship, over time, of the hydraulic liquid to be deliver. The processor 310 may be further configured to comprise a delivery profile, the delivery profile setting the duration of the valve 250 being closed and opened and the timing when to open or close of the valve 250 in relation to the rotation position of the rotor 110 or cam 210, the delivery profile comprising at least a predetermined pressure and flow relationship, over time, of the hydraulic liquid to be deliver. The controller 300 may thereby control the volume, flow, and pressure of the hydraulic liquid to the outlet 270 and the load on the electric motor 100, both over time. For example, the delivery profile may be to provide a high flow of pressurised hydraulic liquid in the beginning of an operation performed with a tool, and subsequently the delivery profile provides a lower flow of pressurised hydraulic liquid in the end of an operation performed with the tool. In the example the pressures may be the same or differ. The delivery profile may be configured for a specific, predetermined, tool and / or a specific, predetermined, operation and / or machine. The delivery profile may be predetermined and selectable provided by the controller 300 for a user to select. The delivery profile may be programmed by configuring the controller 300. The delivery profile may be triggered by the use of a tool or machine 450.

[0039] According to one embodiment, the processor 310 may be further configured to be programmable to set rotational speed, rpm, of the electric motor 100, and setting the delivery profile keeping the load of the electric motor 100 substantially constant by additionally adjusting the rotational speed, rpm, of the electric motor 100. The delivery profile may, for example, be set to control the load the electric motor 100 in a predetermined window so that the system does not use too much energy.

[0040] According to one embodiment, the processor 310 is further configured to be programmable to set the delivery profile dependent on a predetermined hydraulic tool or machine 450. For example, the processor 310 may be configured to set the delivery profile according to a predetermined tensioning duty cycle of the hydraulic tool or machine 450. The delivery profile may be set, triggered, by the use, or operation, of the hydraulic tool or machine 450. The controller 300 may store in the memory 330 a plurality of different delivery profiles that may be selected by an operator or by the hydraulic tool or machine 450 connected to the system.

[0041] According to one embodiment, the controller 300 may be configured to control a tensioning duty cycle of a hydraulic tool or machine. For example, the controller 300 may control a bolt or clamp tensioning duty cycle. The tensioning duty cycle may be predetermined for a predetermined hydraulic tool or machine, and the tension duty cycle may be preprogrammed in the controller 300, for example stored in the memory 330.

[0042] According to one embodiment, the controller 300 may be configured to communicate with one or more controllers 300 of similar systems. The plurality of controllers 300, each controlling a system, may be connected to each other for transferring data and commands. Preferably the connection is wireless, or routed to an operators mobile electronic device or mobile telephone that in turn makes the connections.

[0043] According to one embodiment, the controller 300 may be configured to control one or more pumps of similar systems. The controller 300 may be configured to synchronise a plurality of pumps. For example, operators working on large structures may need to tension bolts in a specific order and at the same time. For example, three operators with each a system as described herein may have two systems connected and controlled by the third device. In this way the third system can control all three systems, for example in such a way that a tensioning duty cycle is performed simultaneously by all three systems. For example, an operation may be initiated by an operator operating the third system. The controller 300 of one system may control other controllers of similar systems, the controller 300 may be given commands by a mobile handheld device of a user and such command may be received and executed by all connected systems.

[0044] According to one embodiment, the controller 300 may be configured to connect to a Global Positioning System, GPS, for receiving a location position of the system. This allows the controller 300 to verify what operations have been done where, and preferably store such data in a memory 330.

[0045] According to one embodiment, the controller 300 may be configured to connect wirelessly to the Internet. This may be one way of the controller 300 to connect to other systems, and may be one way to provide data collected by the controller to a server or other remote device. As disclosed herein, data stored in the memory 330 may be uploaded by the controller to a server or other remote device.

[0046] According to one embodiment, the controller 300 may be configured to collect, save, and upload data concerning one or more of the following: a tool identification, a load applied by a tool, a torque applied by a tool, pressure delivered by the system, physical location, a bolt identification, a user identification, a joint identification, a machine identification, date, time, degree angle of turn of a fastener, and an image. The controller 300 may comprise a memory 330 and the processor 310 may be configured to store and retrieve data to and from the memory 330. The controller 300 may collect the data in the memory 330 of the controller 300. The data may be transferred to a remote storage or server that the system may contact, for example over the internet, preferably wireless.

[0047] According to one embodiment, the controller 300 may be configured to connect wirelessly to a mobile handheld device for transferring data between the two. The controller 300 may be configured to be controlled by instructions from the mobile handheld device. The system may be controlled by commands from the mobile handheld device to provide hydraulic liquid at predetermined pressures. The data collected as mentioned herein may be uploaded to the mobile handheld device. The data may in turn be uploaded to a server or other remote device.

[0048] According to one embodiment, the controller 300 may be configured to control or monitor a hydraulic tool or machine hydraulically connected to the system. The controller 300 may for example control an operation performed by a hydraulic tool and also monitor the operation, for example detect and store captured data, for example a fastener identification, and connect to this data the physical location of the fastener and the load, pressure, or torque applied to the fastener. As described herein, such data may be stored and sent to a remote device.

[0049] According to one embodiment, the controller 300 may be configured to provide a visible, vibration, or audible indication that at least a part of the system is pressurised. To know if a part of the system is pressurised, for example if one of the fluid lines 410, 425, or 430, or the outlet 270, comprises pressurised hydraulic liquid may be indicated by the system. There may for example be a light signal indicating no pressure, for example safe low pressure, and another light signal indicating the presence of high pressure in the system.

[0050] According to one embodiment, the controller 300 may be configured to receive and store captured data from a tool 450. The tool may feed back data about the hydraulic operation performed by the tool 450 in the form of ultrasound and / or image, for example a photo. This data may be received by the controller 300 and stored in a memory 330 of the controller. The captured data may confirm that the operation has been correctly completed, for example by showing a photo of the final step of the operation, for example a tightened bolt, an ultrasound, or other measurement or operation.

[0051] According to one embodiment, the system may further comprise a control valve 420 in fluid communication with the outlet 270; a tank 400 for the hydraulic fluid; a first flow line 425 for delivering the hydraulic fluid from the control valve 420 to the tank 400; and a second flow line 430 for delivering the hydraulic fluid from the tank 400 to the pump 200. This embodiment is described in more detail herein before and after.

[0052] According to one embodiment, the system may further comprise a display 320 connected to the controller 300. The controller 300 may be configured for displaying on the display 320 the delivery profile with the predetermined pressure and flow relationship, over time, of the hydraulic liquid to be deliver. The controller 300 may also be configured for displaying on the display 320 the pressure delivered by the system. The visible indication may also be displayed on the display 320.

[0053] According to one embodiment, a method of using the system according to any one of the embodiments disclosed herein is disclosed. The method comprises the following steps taken in any order: connecting 710 at least two systems according to any one of the embodiments disclosed herein, the connection being a wireless data connection between the at least two systems for transferring control commands and data; delivering 720 pressurised hydraulic liquid to at least one hydraulic tool, or machine, for performing an operation; and collecting 730 data concerning the operation from all the connected systems. The connection 710 may be made in any way as described herein. For example, via the internet, or via mobile handheld devices that are on the same or different networks. For example, one and the same mobile handheld device may have direct data connection, for example blue tooth, with each controller 300 of the at least two systems. The controller 300 may be configured for making this connection 710. The delivery 720 of the pressurised hydraulic liquid may be made at a predetermined pressure set by one of the systems. The hydraulic tool or machine 450 may then perform an operation using the pressurised hydraulic liquid. The data collected in step 730 may be stored in a memory 330 of the controller 300. The data may be any data as described herein.

[0054] According to one embodiment, the method may further comprise the step of connecting 740 a hydraulic tool or machine 450 to each of the at least two systems, and delivering 650 at the same time hydraulic liquid to each of the hydraulic tools or machines 450. For example, three systems may be connected and each of the systems may have a hydraulic tool 450 connected. Pressurised hydraulic liquid may be delivered to the three tools 450 at the same time by each of the systems so that the tools can perform their operation simultaneously.

[0055] According to one embodiment, a system delivering hydraulic liquid for a hydraulic tool or machine at different controllable pressures and flows is disclosed. The system comprises an electric motor 100, a pump 200, a controller 300, and a pressure sensor 290. The electric motor 100 may be a frameless electric motor. The electric motor 100 comprises a rotor 110 and a stator 120. The pump 200 is a plunger-type pump and comprises a cam 210, a cam shaft 220, a plunger 230, a plunger chamber 240, and a valve 250. The valve 250 opens or closes an inlet 260 for the hydraulic liquid to the plunger chamber 240. The plunger chamber 240 comprises an outlet 270. The plunger 230 engages the cam 210, preferably directly. The cam shaft 220 is connected to the rotor 110. The connection may be direct, for example the cam shaft 220 may support the rotor 110.

[0056] The controller 300 is configured to control the opening or closing of the valve 250 in relation to rotational position of the rotor 110 or cam 210 thereby controlling the volume and pressure of the hydraulic liquid to the outlet 270. Controlling the opening or closing of the valve 250 may control how much hydraulic liquid enters and how much hydraulic liquid is compressed by the plunger 230 in the plunger chamber 240 to then exit the outlet 270.

[0057] The pressure sensor 290 senses pressure of the hydraulic liquid exiting the outlet 270. Preferably the pressure sensor 290 is in connection with the outlet 270, after a check valve 280 in the outlet 270, and preferably before a connector 440, for example a coupling or nipple. The pressure sensor 290 may be connected to the controller 300 for transferring pressure data to the controller 300.

[0058] The controller 300 is further configured to open the valve 250 in relation to the rotational position of the cam 210 when the pressure sensor 290 senses a predetermined pressure of the hydraulic liquid thereby limiting the flow and pressure to the outlet 270. The plunger 230 may, with an open valve 250, pump hydraulic liquid back through the inlet 260 instead of through the outlet 270. When the pressure sensor 290 senses that the pressure drops below the predetermined pressure, then the controller 300 may close the valve 250 such that the plunger 230 compresses hydraulic liquid in the plunger chamber 240 and out via the outlet 270, when the plunger 230 moves upward with reference to figures 1 and 2. The control valve 420 may also be controlled to be opened to the connector 440, and optionally closed to the tank 400, by the controller 300 when the pressure sensor 290 senses the predetermined pressure of the hydraulic liquid.

[0059] The controller 300 may be further configured to maintain rotating the cam 210 with the electric motor 100 while opening the valve 250 when the pressure sensor 290 senses the predetermined pressure. With the electric motor 100 running, when the valve 250 is open the hydraulic liquid may be circulating within the pump 200 in fluid circulation lines 254. The plunger 230 may, with an open valve 250, pump hydraulic liquid back through the inlet 260 instead of through the outlet 270, and the hydraulic liquid may circulate within the pump 200.

[0060] The controller 300 may be further configured to maintain one of a plurality of predetermined pressures by closing the valve 250 late when the plunger 230 moves to compress the hydraulic liquid in the plunger chamber 240 such that only a part of the plunger chamber 240 contains the hydraulic liquid to be compressed by the plunger 230, while keeping the electric motor 100 running and rotating the cam 210. The other part of the plunger chamber 240 with the hydraulic liquid may be made to circulate within the pump 200, for example in the fluid circulation lines 254. The plurality of predetermined pressures may include at least 150 MPa and 250 MPa.

[0061] The controller 300 may be further configured to control when the valve 250 closes to allow the plunger 230 to pump some amount of the hydraulic liquid in the plunger chamber 240 back through the inlet 260 before closing the valve 250. The plunger 230 may compress the remaining hydraulic liquid in the plunger chamber 240 and out through the outlet 270, thereby controlling the flow and pressure of the hydraulic liquid to the outlet 270. This is further described herein.

[0062] The controller 300 may be further configured to control the rotational speed, rpm, of the electric motor 100, and thereby the rotational speed of the cam 210, to control the flow and pressure of the hydraulic liquid to the outlet 270. A lower rpm may result in a lower flow of pressurised hydraulic liquid through the outlet 270, while a higher rpm may result in a higher flow of pressurised hydraulic liquid through the outlet 270.

[0063] The controller 300 may be further configured to control the load of the pump 200 on the electric motor 100 to be substantially constant by controlling when the valve 250 closes and controlling the rotational speed, rpm, of the electric motor 100. For example, the load on the electric motor 100 may be held substantially constant by only controlling when the valve 250 closes and the rotational speed, rpm, of the electric motor 100. The load may be held constant with a lower rpm with the valve 250 closing late allowing less hydraulic liquid to be compressed in the plunger chamber 240 and therefore controlling the load on the electric motor 100. The load may be held constant with a higher rpm with the valve 250 closing earlier allowing more hydraulic liquid to be compressed in the plunger chamber 240 and therefore controlling the load on the electric motor 100.

[0064] The system may further comprise at least two connectors 440, for example quick connect couplings, for delivering hydraulic liquid at a first and a second predetermined pressure, respectively. The first predetermined pressure may be lower than the second predetermined pressure. The controller 300 may be further configured for setting the maximum allowable pressure to be delivered to the outlet 270 depending on to which one of the two connectors 440 a hydraulic tool or machine is connected. The connectors 440 may be quick connect couplings, for example couplings and / or nipples. The controller 300 may be connected with a sensor sensing which one of the two connectors 440 has been connected and then limit the supply of pressurised hydraulic liquid accordingly.

[0065] The system may further comprise at least two connectors 440, for example quick connect couplings 440, for delivering hydraulic liquid at a first and a second predetermined pressure, respectively. The first predetermined pressure may be lower than the second predetermined pressure. The system may further comprise blocking means 446 for ensuring the correct connector of the at least two connectors 440 is used for connecting a hydraulic tool or machine when the system is set to one of the first and second predetermined pressures. The correct connector is naturally the connector that is configured for the pressure delivered by the system. For example, if hydraulic liquid at the second predetermined pressure is delivered to the outlet 270, then the blocking means 446 will block the connector 440 for delivering the first hydraulic liquid at the first predetermined pressure. This provides safety for making the correct connections to the system.

[0066] The system may further comprise a connector 440 for at least a first predetermined pressure, the first predetermined pressure being lower than a second predetermined pressure. The connector 440 may comprise a front part 442 and a back part 444. The back part 444 may be attached to the pump 200 and the front part 442 may be connectable to another connector, the back part 444 being configured for the second predetermined pressure, and the front part 442 being configured for the first predetermined pressure. The connector 440 may be a quick connect coupling. This may allow tools for a lower pressure, for example 150 MPa, to be connected to the pump, even if the pump could produce a high pressure, for example 250 MPa, that is too high for such tools. Since the back part 444 may be configured for the higher pressure, this example enables safe back pressure up to 250 MPa.

[0067] According to one embodiment, any one of the systems disclosed herein may further comprise a check valve 280. The check valve 280 may be positioned in the outlet 270, between the plunger chamber 240 and the pressure sensor 290. The check valve prevents hydraulic liquid to flow back into the plunger chamber 240. The check valve may be spring loaded with a spring 282.

[0068] According to one embodiment, the system may further comprise a circular flow line 254 for the hydraulic liquid inside the pump 200, the valve 250 being in fluid connection with the circular flow line 254. The tank 400 may be in fluid connection with the circular flow line 254. The circular flow line 254 may be feeding the plunger chamber 240 with hydraulic liquid via the valve 250 and the inlet 260.

[0069] According to one embodiment, the system may further comprise a feed pump, for example a cog wheel pump, for supplying hydraulic liquid to the plunger chamber 240. The supply of hydraulic liquid may come from the tank 400. The feed pump may feed the hydraulic liquid via the circular flow line 254 to the plunger chamber 240.

[0070] According to one embodiment, the system may further comprise a control valve 420, for example a solenoid valve 420, that may be in fluid communication with the outlet 270. The control valve 420 may be connected for data transfer to the controller 300 and may be controlled to be opened or closed by the controller 300. The controller 300 may open or close the control valve 420 depending on the pressure sensed by the pressure sensor 290. The control valve 420 may be arranged in fluid communication between the check valve 280 and the connector 440, preferably between the pressure sensor 290 and the connector 440. For example, the controller 300 may open the control valve 420 when the controller 300 notices that the predetermined pressure, sensed by the pressure sensor 290, is reached. In this example the tool 450 is provided with the predetermined pressure of hydraulic liquid when the control valve 420 opens. The control valve 420 may optionally open or close a first fluid line 425 to the tank 400. A second fluid line 430 may go from the tank 400 to the pump 200. In this way hydraulic fluid, preferably not pressurised, may be collected in the tank 400 and fed, for example by the feed pump, to the pump 200. The control valve 420 may, as explained herein, direct hydraulic liquid to the connector 440 when the predetermined pressure is reached, and, for example when the hydraulic tool is not used or after it has been used, guide the hydraulic liquid back to the tank 400.

[0071] According to one embodiment, the electric motor 100 may be a frameless electric motor. The rotor 110 of the frameless electric motor 100 may be supported by the cam shaft 220, preferably by one end of the cam shaft 220.

[0072] According to one embodiment, the system may further comprise an outer protective frame or structure of composite fibre or other material. Such an enclosure protects the system and at the same time provides a system that may be carried by hand by a human operator. The protective frame may also be configured to provide a stable stand for the system.

[0073] According to one embodiment, the controller 300 may control when the valve 250 opens or closes depending on the number of rotations per minute, rpm, of the electric motor 100. For each rotation the valve 250 may open once and close once. For example, for a low number of rpm of the electric motor 100 the valve 250 may close late allowing less hydraulic liquid to be compressed in the plunger chamber 240. For example, for a high number of rpm of the electric motor 100 the valve 250 may close when the plunger 230 is at its lowest position for allowing hydraulic liquid to, preferably completely, fill the plunger chamber 240 to be compressed.

[0074] According to one embodiment, the system may further comprise a tank for the pressurised hydraulic liquid, the tank being in fluid communication with the outlet 270, and the tank comprising a quick connect coupling for connecting a hose to a tool or machine 450. The tank may provide a buffer of pressurised hydraulic liquid to the tool or machine 450. However, preferably such a tank is not necessary because the system as described herein provides sufficient pressure and flow of the hydraulic liquid to feed the tool directly.

[0075] Any one of the embodiments disclosed herein may be combined with any part of any other embodiment disclosed herein and / or with the following description of the drawings. The drawings, especially figures 1 and 2, illustrate exemplary embodiments of the disclosure and serve to explain, by way of example, the principles of the disclosure.

[0076] With reference to figures 1 and 2, a system is illustrated and hereby described, and may, in whole or in part, be combined with any one of the embodiments disclosed herein. The electric motor 100 may be a frameless motor where the rotor 110 rotates around the stator 120. The electric motor 100 may be connected directly to the pump 200, for example wall to wall, without any means therebetween. The electric motor 100 may have a motor housing. The pump 200 may have a pump housing. The motor housing may be directly, or indirectly, connected to the pump housing. As illustrated in figure 1, the motor housing may be attached, for example bolted, directly to the pump housing.

[0077] The cam shaft 220 may be connected directly to the rotor 110, preferably supported by one end of the cam shaft 220. Bearings for the rotor 110 in the electric motor 100 may not be necessary since the rotor 110 and the cam shaft 220 may be connected. As illustrated in figure 1, the cam shaft 220 may be directly connected to the rotor 110. This provides a compact and sturdy system of the electric motor 100 and the pump 200. Bearings may be provided for the cam shaft 220, for example on each side of the cam 210.

[0078] The rotation of the rotor 110 and therefore also the camshaft 220 may be detected by sensors 130, 140. The sensors may for example be a hall detector sensing a magnet. While only one pair of sensors 130, 140 has been illustrated, there may be more sensors such that a very accurate position, for example angular position, can be determined. Since the rotation of the rotor 100 may be detected, the rotational position of the cam 210 may also be determined. The angle of the cam 210 may hereby be determined. The sensors 130, 140 may therefore be able to indicate if the plunger 230 is on its way down or up, and exactly where the plunger 230 is in the plunger chamber 240. The sensors 130, 140 are coupled for data transfer to the controller 300 and the controller 300, with its processor 310, therefore knows where the plunger 230 is. The controller 300 is also connected to the electric motor 100 and may control the rotational speed of the electric motor 100 and can therefore control how the plunger 230 moves, for example how fast, for example how may strokes the plunger 230 makes during a predetermined time unit. The controller 300 may in this way, together with the control of opening and closing the valve 250, control the pressure and flow of hydraulic liquid to the outlet 270.

[0079] With further reference to figures 1 and 2, the pump 200 is a plunger-type pump 200. The pump 200 may have a single plunger 230 movable inside a plunger chamber 240. The pump 200 may have two plungers 230, preferably they would be moving in opposite directions of each other to balance the rotational force for rotating the plungers 230. One and the same electric motor 100 may drive the two plungers 230. The two plungers 230 may be engaging the one and the same cam 210. Each plunger 230 may be movable within its own plunger chamber 240. The pump 200 may have more than two plungers 230. As illustrated in figures 1 and 2, the pump 200 comprises the cam 210, the cam shaft 220, the plunger 230, the plunger chamber 240, and the valve 250. The pump 200 may also comprise the control valve 420, the tank 400, and the fluid lines 425, 430. The plunger 230 may be forced against the cam 210 by a spring 232. In this way the plunger 230 may slide up and down in figures 1 and 2 as the cam 210 rotates by constantly engaging the surface of the cam 210. The valve 250 is configured for opening or closing the inlet 260 for the hydraulic liquid to the plunger chamber 240. The opening and closing of the valve 250 may be controlled by the controller 300. The plunger chamber 240 comprises an outlet 270 for the hydraulic liquid. The outlet 270 may have a check valve 280 allowing hydraulic liquid pushed by the plunger 230 into the outlet 270 to pass through and out of the pump to, for example a tool 450. The check valve 280 may have a check valve spring 282 ensuring that the hydraulic liquid can only flow in one direction, out of the pump, not into the pump. Hydraulic liquid may thus only flow to the right through the check valve 280 in figure 1.

[0080] A pressure sensor 290 sensing pressure of the hydraulic liquid to be delivered is illustrated in figure 1. The pressure sensor 290 may be arranged in the outlet 270 and after the check valve 280 in the flow direction. One or more pressure sensors 290 may be arranged in the pump 200 and / or at a tool 450. The pressure sensor 290 may be connected to the controller 300 such that the controller 300 may read the pressure sensor 290. In this way the controller 300 knows what pressure the pump is delivering. A pressure signal from the pressure sensor 290 may be fed to the controller 300, and the controller 300 may subsequently adapt the rotational speed of the rotor 110 and the position of the valve 250 to regulate the flow and pressure provided by the pump 200, for example matching the pressure to a predetermined pressure.

[0081] The controller 300 is configured to control the opening and closing of the valve 250 in relation to pressure sensed by the pressure sensor 290 and rotational position of the rotor 110 or cam 210. The controller 300 may thereby control the volume, flow, and pressure of the hydraulic liquid to the outlet 270 and the load on the electric motor 100. The controller may be further configured to open the valve 250 in relation to the rotational position of the cam 210 when the pressure sensor 290 senses a predetermined pressure of the hydraulic liquid thereby limiting the flow and pressure to the outlet 270. The controller 300 comprises the processor 310, and the processor 310 may be configured to control the opening and closing of the valve 250 in relation to pressure sensed by the pressure sensor 290 and rotational position of the rotor 110 or cam 210. The processor 310 may be configured to control the rotational speed, rpm, of the motor 100. The processor 310 may be further configured to be programmable to set a delivery profile setting the duration of the valve 250 being closed and opened, and the timing when to open or close of the valve 250 in relation to the rotation position of the rotor 110 or cam 210. The delivery profile comprises at least a predetermined pressure and flow relationship, over time, of the hydraulic liquid to be deliver.

[0082] As illustrated in figures 1 and 2, the controller 300, with its processor 310, may regulate the opening and closing of the valve 250 and regulate the movement of the plunger 230. In general, the valve 250 opens and hydraulic liquid moves from the inlet 260 into the plunger chamber 240. In a full, maximised, stroke the valve 250 closes when the plunger 230 starts to move upwards. In this way all the hydraulic liquid in the plunger chamber 240 is moved out via the outlet 270. This puts a load on the electric motor. The valve 250 may close shortly after the plunger 230 starts to move upwards. In this way some of the hydraulic liquid in the plunger chamber 240 is moved out via the outlet 270, but some is moved back into the inlet 260 because the valve 250 closed late. This puts a lesser load on the electric motor. In this way the flow, pressure and load of the system may be controlled. The valve 250 may be held open and the plunger 230 may be moving. In this way the electric motor 100 and the pump 200 is running, but no pressurised hydraulic liquid is supplied. This allows the system to be idle and spring quickly into action providing pressurised hydraulic liquid without any long build up of the pressure such as in a two-stage positive displacement pump.

[0083] As illustrated best in figure 1, a connector 440 may be used for connecting a hose 410 for the hydraulic liquid from the outlet 270 to a tool or machine 450. The pressurised hydraulic liquid may go directly via the hose 410 to the tool or machine 450. The hose 410 may comprise a return hose. The pressurised hydraulic liquid may be returned, flow back, via the same hose 410 or the return hose. A control valve 420, for example a solenoid valve 420, may be in fluid communication with the outlet 270. The control valve 420 may be connected for data transfer to the controller 300 and may be controlled to be opened or closed by the controller 300. The controller 300 may open or close the control valve 420 depending on the pressure sensed by the pressure sensor 290. The control valve 420 may be arranged in fluid communication between the check valve 280 and the connector 440, preferably between the pressure sensor 290 and the connector 440. For example, the controller 300 may open the control valve 420 when the controller 300 notices that the predetermined pressure, sensed by the pressure sensor 290, is reached. In this example the tool 450 is provided with the predetermined pressure of hydraulic liquid when the control valve 420 opens.

[0084] The control valve 420 may open to a tank 400 via a hose 425. The tank 400 may be pressurised, but preferably not be pressurised. The tank 400 may supply hydraulic liquid to the pump 200 via a hose 430 to the vale 250, and if the valve 250 is open, to the inlet 260 of the plunger chamber 240. A feeder pump, for example a cog wheel pump, may move the hydraulic liquid from the tank 400 to the pump 200 via hose 430. The feeder pump may not pressurise the hydraulic liquid. The hydraulic liquid may be fed to the circular flow line 254. The hydraulic liquid may also be returned to the tank 400.

[0085] As illustrated by figures 1 and 2, the plunger 230, the plunger chamber 240, and the cam 210 of the plunger-type pump are not submerged wetted piston elements. Instead, the tank 400 may provide the hydraulic liquid to the valve 250. There is no need to submerge any part of the pump 200 in hydraulic liquid. Instead hydraulic liquid is only fed to the plunger chamber 240 and the plunger 230 compresses the hydraulic liquid without any leakage or need for submerged parts in the pump.

[0086] Embodiment of the system disclosed herein may be a static system. That is, the pressure of the hydraulic liquid provided out of the outlet 270, and the control valve 420, and to the connector 440 is at the constant predetermined pressure. There is no need to first wait for the pressure to build up or have a pressurised tank between the pump 200 and a tool 450. Instead, embodiments of the present system may build up the pressure very quickly, almost instant, and keep that pressure, i.e. a static pressure system. As disclosed herein, the controller 300 keeps the predetermined pressure at a static predetermined level. The tool or machine 450 uses the predetermined pressurised hydraulic liquid when the control valve 420 is opened by the controller 300. The predetermined pressurised hydraulic liquid is not discharged, leaked, or consumed by the tool or machine 450, instead it is static, because of the flow of the hydraulic liquid within the system as described herein. The system is circular and keeps the hydraulic liquid pressurised and ready for use by the tool or machine 450. Other system for pumping liquid that is consumed cannot be used and are not relevant, because they do not allow for a static system and are unsuitable for providing hydraulic liquid to a machine tool or machine.

[0087] There is no need to set, adjust, any valve manually as must be done in prior high pressure pumps. The system as described with the controller 300 controls the setting so that the desired pressure is reached and held. This is done automatically by the described system without the need for manual adjustment. The change from one predetermined pressure to another predetermined pressure is very smooth with no sudden pressure changes or pulsation that wears hoses and connectors down, because the controller 300 can control how much hydraulic liquid the plunger 230 is compressing in the plunger chamber 240 as described herein. In addition, since the controller 300 handles the adjustment to get to the predetermined pressure no human errors are made

[0088] The connector 440 may be a quick connect coupling, and the pump 200 may comprise a female or male part of a connector. Two connectors may be used, one for a first predetermined pressure, for example 150 MPa, and another for a second predetermined pressure, for example 250 MPa. There may be means for assisting a user to connect to the right connector, for example the controller 300 may provide blocking means 446 to ensure that a user connects to the correct connector 440.

[0089] The quick connect coupling 440 may be for at least a first predetermined pressure, the first predetermined pressure being lower than a second predetermined pressure. The quick connect coupling 440 may comprising a front part 442 and a back part 444, the back part 444 being attached to the pump 200 and the front part 442 being connectable to another connector, for example a nipple or a coupling. The back part may be configured for the second predetermined pressure, and the front part being configured for the first predetermined pressure. In this way only one connector 440 may be used and / or the system is safe to use.

[0090] The system may comprise a safety valve that can release pressure, either when internal pressure is too high. The safety valve provides safe working of the combination of electric motor 100 and pump 200. The safety valve may be part of the connector 440.

[0091] The controller 300 may control one or more pumps. The controller 300 may connect, via cable or wireless, to another controller 300. In this way two systems with each a pump, may be controlled by one and the same controller 300. For example, if a plurality of systems are each connected to a tool, the controller 300 of one of the systems may then control the other systems such that the pump of each system may for example start at the same time so that each tool operates simultaneously. The controller 300 may be connected for data transfer to the sensors 130, 140, 150, 290 and to the valves 250, 420.

[0092] The controller 300 may also collect data, as described herein, such that one may later retrieve the data to verify what operations have been performed. For example, if ten fasteners are to be fastened with a specific load, pressure, or torque, then the controller may collect and store identification data of each fastener and also collect and store the load, pressure, or torque used by the tool. In this way the systems may be used to collect data of the operations performed.

[0093] The controller may comprise a display 320. The display 320 may be interactive and for example show the pressure delivered and / or the delivery profile provided. The display 320 may also provide a visible indication that at least a part of the system is pressurised. The display 320 may have an interface to give commands to the controller 300, for example a user may set a pressure, for example 250 MPa, that the system should deliver. A user may the display 320 with the interface to, for example, set or program a delivery profile, as disclosed herein, that the system should deliver.

[0094] With reference to figure 3 a method is disclosed. The method provides hydraulic liquid at different predetermined and controllable pressures with a system as described herein. The method comprises running 610 the pump 200 with the electric motor 100 and sensing 620 the pressure of the hydraulic liquid to be delivered. By controlling 630 the opening and closing of the valve 250 in relation to pressure sensed by the pressure sensor 300 and rotational position of the rotor 110 or cam 210, the controller 300 controls the volume and pressure of the hydraulic liquid to the outlet 270 and also the load on the electric motor 100. The load on the electric motor 100 may be controlled 640 to be substantially constant by adjusting when to open and close the valve 250 in relation to the rotational position of the rotor 110 or the cam 210 and the pressure sensed by the pressure sensor 290.

[0095] With reference to figure 4 a method is disclosed. The method uses any embodiment of the system as described here and allows to connect several systems. In this way a controlled operation of several high-pressure pumps may supply several tools simultaneously with high pressure hydraulic liquid. The method comprises the following steps taken in any order: connecting 710 at least two systems according to any one of the embodiments disclosed herein, the connection being a wireless data connection between the at least two systems for transferring control commands and data; delivering 720 pressurised hydraulic liquid to at least one hydraulic tool, or machine, preferably to all connected tools or machines, for performing an operation; and collecting 730 data concerning the operation from all the connected systems. The method may be only steps 710 and 720. The method may further comprise connecting 740 a hydraulic tool or machine 450 to each of the at least two systems, and delivering 650 at the same time hydraulic liquid to each of the hydraulic tools or machines 450.

[0096] A technical effect of at least one of the above disclosed embodiments is that the system and / or method provides a high-pressure pump, for delivering hydraulic liquid, that is inexpensive to manufacture, light, silent, and easy to use. At least one embodiment of the pump may produce different predetermined pressures, different flows, and may be controlled in an easy and programmable way. At least one embodiment of the pump may give specific tools or machines a specific delivery profile of hydraulic liquid.

[0097] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using the systems and performing the methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.List of elements

[0098] 100 electric motor 110 rotor 120 stator 130 sensor, position 140 sensor, position 150, sensor, temperature 160 battery 200 pump 210 cam 220 cam shaft 230 plunger 240 plunger chamber 250 valve 252 valve spring 254 circular flow line 260 inlet 270 outlet 280 check valve 282 check valve spring 290 sensor, pressure 300 controller 310 processor 320 display 330 memory 400 tank 410 hose from pump to tool 420 control valve 425 hose from pump to tank 430 hose from tank to pump 440 connector 442 front part of connector 444 back part of connector 446 blocking means preventing access to connector 450 tool or machine 610 to 670 method steps 710 to 750 method steps

Claims

1. A system delivering hydraulic liquid at different predetermined and controllable pressures for a hydraulic tool or machine, the system comprising: an electric motor (100) comprising a rotor (110) and a stator (120); a pump (200), the pump being a plunger-type pump and comprising a cam (210), a cam shaft (220), a plunger (230), a plunger chamber (240), and a valve (250), the valve (250) opening or closing an inlet (260) for the hydraulic liquid to the plunger chamber (240), the plunger chamber (240) comprising an outlet (270) for the hydraulic liquid, the plunger (230) engaging the cam (210), and the cam shaft (220) being connected to the rotor (110); a pressure sensor (290) sensing pressure of the hydraulic liquid to be delivered; and a controller (300) configured to control the opening and closing of the valve (250) in relation to pressure sensed by the pressure sensor (300) and rotational position of the rotor (110) or cam (210), the controller (300) thereby controlling the volume and pressure of the hydraulic liquid to the outlet (270) and the load on the electric motor (100).

2. The system according to claim 1, wherein the controller is further configured to control the load on the electric motor to be substantially constant by adjusting when to open and close the valve (250) in relation to the rotational position of the rotor (110) or the cam (210) and the pressure sensed by the pressure sensor (290).

3. The system according to claim 1 or 2, wherein the controller (300) is further configured to control the opening or closing of the valve (250) in relation to rotational position of the rotor (110) or cam (210) to provide at least two predetermined pressures of 1500 bar and 2500 bar of the hydraulic liquid to the outlet (270).

4. The system according to any one of the preceding claims, wherein the electric motor (100) is a frameless electric motor with the cam shaft (220) connected directly to the rotor (110), the system comprising one or more bearings for the cam shaft (220) only at a distal part of the cam shaft (220) away from the rotor (110).

5. The system according to any one of the preceding claims, further comprising a temperature sensor (150) for sensing temperature of the electric motor (100), the controller (300) being further configured to detect the temperature of the electric motor (100) and configured to control the opening and closing of the valve (250) in relation to the temperature.

6. The system according to any one of the preceding claims, further comprising at least one sensor (130, 140) for sensing rotational position of the rotor (110), the controller (300) being further configured to detect the rotational position of the rotor (110), and thereby the position of the plunger (230), via the sensor (130).

7. The system according to claim 6, comprising at least two sensors (130, 140), on the rotor (110), cam shaft (220), or cam (210); one sensor for detecting the lowest position of the plunger (230) and one sensor for detecting the highest position of the plunger (230).

8. The system according to any one of the preceding claims, further comprising a battery pack (160) for providing the controller (300) and the electric motor (100) with electric power; and the controller (300) is further configured for reducing electric power consumption of the electric motor (100) by controlling the opening and closing of the valve (250) in relation to rotational position of the rotor (110) or cam (210) and pressure sensed by the pressure sensor (300), and by controlling rotational speed, rpm, of the electric motor (100).

9. The system according to any one of the preceding claims, further comprising a control valve (420) in fluid communication with the outlet (270); a tank (400) for the hydraulic fluid; a first flow line (425) for delivering the hydraulic fluid from the control valve (420) to the tank (400); and a second flow line (430) for delivering the hydraulic fluid from the tank (400) to the pump (200).

10. The system according to any one of the preceding claims, the controller (300) being further configured to deliver a predetermined flow deliver profile of the hydraulic pressure to the outlet (270), the delivery profile comprising at least a predetermined pressure and flow relationship of the delivered hydraulic liquid.

11. The system according to any one of the preceding claims, further comprising a connector (440) in fluid connection with the outlet (270), the connector (440) being configured for at least a first predetermined pressure, the first predetermined pressure being lower than a second predetermined pressure, the connector (440) comprising a front part (442) and a back part (444), the back part (444) being attached to the pump (200) and the front part (442) being connectable to another connector, the back part (444) being configured for the second predetermined pressure, and the front part (442) being configured for the first predetermined pressure.

12. A method for providing hydraulic liquid at different predetermined and controllable pressures, comprising providing a system according to any one of the preceding claims; the method comprising rotating (610) the electric motor (100); sensing (620) pressure of the hydraulic liquid to be delivered; and controlling (630) the opening and closing of the valve (250) in relation to pressure sensed by the pressure sensor (290) and rotational position of the rotor (110) or cam (210), the controller (300) thereby controlling the volume and pressure of the hydraulic liquid to the outlet (270) and the load on the electric motor (100).

13. The method according to claim 10, further comprising controlling (640) the load on the electric motor (100) to be substantially constant by adjusting when to open and close the valve (250) in relation to the rotational position of the rotor (110) or the cam (210) and the pressure sensed by the pressure sensor (290).

14. The method according to claim 10, further comprising controlling (650) the opening or closing of the valve (250) in relation to rotational position of the rotor (110) or cam (210) to provide at least two predetermined pressures of 150 MPa, 1500 bar, and 250 MPa, 2500 bar, of the hydraulic liquid to the outlet (270).

15. The method according to claim 10, further comprising detecting (660) the temperature of the electric motor (100) and controlling the opening and closing of the valve (250) in relation to the temperature; and / or detecting (670) rotational position of the rotor (110), and thereby the position of the plunger (230).

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