WO2024068830A1

WO2024068830A1 - System for conditioning a cooling lubricant emulsion

Info

Publication number: WO2024068830A1
Application number: PCT/EP2023/076873
Authority: WO
Inventors: Manfred SCHNEEBERGER
Original assignee: Liquidtool Systems Ag
Priority date: 2022-09-28
Filing date: 2023-09-28
Publication date: 2024-04-04

Abstract

The invention relates to a system (100) for conditioning a cooling lubricant emulsion for machine tools (10) comprising: a measuring unit (300) comprising at least one sensor for determining at least one parameter of the cooling lubricant emulsion, a providing unit (200) for providing fresh cooling lubricant emulsion, which is configured to mix a defined amount of a concentrate with a defined amount of water, and to provide the mixture as fresh cooling lubricant emulsion, and a filling level sensor (500) configured to measure the filling level in a tank (60), characterized in that the providing unit (200) is spatially separated from the measuring unit (300) and does not directly exchange liquid with the measuring unit (300), the system (100) furthermore comprising a distributor unit (400) configured to be connected to the measuring unit (300), the providing unit (200) and a tank (60), and to regulate the exchange of cooling lubricant emulsion between them, the system (100) additionally comprising a control unit (600) configured to control the providing unit (200), the measuring unit (300), the distributor unit (400) and the filling level sensor (500) and to exchange data with them.

Description

System for conditioning a cooling lubricant emulsion

The invention relates to a system for use in a method for determining at least one parameter and/or for conditioning a cooling-lubricating emulsion for machine tools, as well as the corresponding method.

State of the art

When workpieces are machined, they are given a specific shape by mechanically separating excess material in the form of chips using a tool. The machining manufacturing processes include, for example, turning, milling, drilling and grinding. Due to friction, the mechanical work introduced is almost completely converted into heat.

Cooling lubricant emulsions, or KSS emulsions for short, are widely used in the metalworking industry for metal cutting. KSS emulsions are often made from KSS concentrates by stirring them into water. KSS concentrates usually consist of an oil component, buffer components, emulsifiers and various additives. KSS concentrates are homogeneous liquid products with an oily consistency.

The cooling lubricant emulsions (KSS) are used to cool and lubricate the workpiece and/or the tool being machined. To do this, the cooling lubricant emulsions are usually pumped from a tank and applied to the tool or workpiece. The cooling lubricant emulsion is then collected and returned.

When the cooling lubricant emulsion is used, it is collected and discharged together with the chips removed from the machining process. The cooling lubricant emulsion adheres to the discharged chips. Before the cooling lubricant emulsion can be used again, it must be freed of chips and other contaminants. In addition, the fine spraying of the cooling lubricant emulsion at the high pressures used in the machines causes water to evaporate. This causes an enrichment of the active components such as oils, additives and the like in the cooling lubricant emulsion.

To compensate for the discharged cooling lubricant emulsion and the water evaporation, cooling lubricant emulsion of low concentration must be regularly refilled, which is referred to as "refilling". The refill quantity and concentration can be calculated from the current actual and target concentration and the level difference in the tank.

GB 2547056 A discloses a system for determining the state of a liquid in a tank. The system comprises one or more sensors, each of which can be used to determine a property of the liquid. Depending on the measured properties, it is determined which amount of concentrate and/or which amount of water must be added in order to achieve a desired state of the liquid.

US 5,389,546 describes a continuous titration process for determining an alkali content of a liquid used for metalworking. The method involves continuously taking a sample of the liquid used for metal processing, mixing it with a continuously increasing stream of a standard solution and continuously determining the pH value. The alkali content can be calculated from the ratio of the two volume flows. The liquid flow during the measurement is continuously disposed of. Alternatively, a sample with a known pH value can be supplied to check an inserted sensor.

WO 2020/126257 discloses a method for determining at least one parameter and/or for conditioning a cooling lubricant emulsion for machine tools, wherein the cooling lubricant emulsion is provided in a tank, wherein cooling lubricant emulsion is removed from the tank and at least one parameter of the cooling lubricant emulsion is detected using at least one sensor. A device for carrying out the method is also disclosed. Disclosure of the invention

A system for conditioning a cooling lubricant emulsion for machine tools is proposed. The system comprises a measuring unit comprising at least one sensor for determining at least one parameter of the cooling lubricant emulsion, a supply unit for supplying fresh cooling lubricant emulsion, which is designed to mix a defined amount of a concentrate with a defined amount of water, and a fill level sensor which is designed to measure the fill level in a tank.

Unlike previously known devices, the supply unit is spatially separated from the measuring unit and is not in direct fluid exchange with it. Instead, the system comprises a distribution unit which is designed to be connected to the measuring unit, the supply unit and a tank in which the cooling lubricant emulsion intended for conditioning is located, and to regulate the exchange of cooling lubricant emulsion between them. In addition, the system according to the invention comprises a control unit which is designed to control the individual components of the system. The expression “in no direct fluid exchange” means that no fluid exchange takes place between the measuring unit and the supply unit that does not take place via the distribution unit. Preferably, the supply unit is designed to be connected to the distribution unit via a single line and to be in fluid exchange with it.

The control unit is preferably set up to carry out at least the following steps: a) controlling the supply unit so that it mixes a defined amount of a concentrate with a defined amount of water and provides the mixture as a fresh cooling lubricant emulsion; b) Activating the distribution unit so that this fresh coolant lubricant emulsion leads from the supply unit into the measuring unit or into the tank, or coolant lubricant emulsion from the tank into the measuring unit, and / or optionally at least part of the coolant lubricant emulsion from the measuring unit leads into the tank; c) receiving measurement data from the at least one sensor of the measuring unit and the level sensor; d) Calculating the amount of follow-up required to transfer the level in the tank from a measured actual level to a defined target level; e) Calculating the follow-up concentration of a fresh coolant lubricant emulsion, which is required for a calculated follow-up quantity in order to convert the measured actual concentration in the tank into a defined target concentration.

During operation of the system according to the invention, the components of the system are connected to one another, with the supply unit being connected to the distribution unit and in liquid exchange, the measuring unit being connected to the distribution unit and in liquid exchange, the distribution unit being in liquid exchange with a tank, and the Control unit has a data connection with the provision unit, the measuring unit and the distribution unit. While the components of the system according to the invention are connected to one another, the system according to the invention can also be referred to as a “device according to the invention”. As long as the components of the system according to the invention are not connected to one another, the system according to the invention can also be referred to as a “component kit” or “component kit”.

According to the invention, the spatial separation of two components means that the two components (e.g. the measuring unit and the provision unit) do not have a common housing, preferably each have a housing.

While the provision unit and the measurement unit are spatially separated from one another, the remaining components of the system can have a common housing with the provision unit, the measurement unit or with each other. For example, the measuring unit can be combined with the distribution unit in one housing. The control unit can also be combined with the provision unit, the measuring unit or the distribution unit in one housing. Alternatively, the measuring unit, provision unit and distribution unit, preferably the measuring unit, provision unit, distribution unit and control unit, are spatially separated from one another. The supply unit of the system according to the invention for providing fresh cooling lubricant emulsion is set up to mix a defined amount of a concentrate with a defined amount of water and to provide the mixture as a fresh cooling lubricant emulsion.

The fresh cooling-lubricating emulsion can be obtained in particular by pumping water and/or concentrate using a volumetric pump and/or by measuring a pumped quantity of water and/or concentrate and regulating a feed pump depending on the measured pumped quantity.

The supply unit therefore preferably comprises at least one volumetric pump to convey the water and/or the concentrate. Alternatively or additionally, the supply unit comprises at least one controllable pump and a flow meter assigned to the pump, with which a volume conveyed by the pump is determined, wherein the supply unit is set up to regulate the pump depending on the volume conveyed. Various combinations are conceivable. For example, water can be conveyed using a controlled pump and the concentrate can be conveyed via a volumetric pump. Suitable volumetric pumps are, for example, peristaltic pumps, gear pumps and piston pumps.

Furthermore, it is possible for a controllable valve to be used in conjunction with a flow meter, in particular to regulate the water inlet, with the valve being controlled depending on the measured flow. The water is preferably obtained from a line under pressure (eg tap water). In this case, the water does not need to be pumped. In this case, the water flow can also be measured without additional regulation. The concentrate is then adjusted to the water flow using a volumetric pump or an adjustable pump and a flow meter. This enables a simple design of the valve through which the water flows, since only the opening and closing of the valve is required. Suitable valves can be, for example, motor-operated valves, solenoid valves, pneumatic valves or hydraulic valves. Solenoid valves are preferred.

Furthermore, it is provided that the provision unit includes a water inlet through which fresh water can be conveyed into the provision unit as described above. The water inlet can, for example, be a connection for a pressurized water pipe through which tap water or treated water, e.g. de-mineralized water or de-ionized water, can enter the supply unit. Alternatively, the water can be transported from a water container into the supply unit. This can be done using a volumetric pump (water pump), with the water inlet connected to a water suction line that is submerged in the water tank. In this case, it can be provided that the system according to the invention comprises a level sensor for determining the water level in the water container.

The supply unit may include at least one check valve to allow water flow in one direction only. This may prevent damage to some sensitive components and may prevent contamination of the fresh water in the water pipe or water tank.

It is further provided that the supply unit comprises a concentrate inlet through which the concentrate of the cooling lubricant emulsion can be conveyed into the supply unit. It is provided that the concentrate is conveyed from a concentrate container into the supply unit.

This can be done using a volumetric pump (concentrate pump) with the concentrate inlet connected to a concentrate suction line which is immersed in the concentrate container. It can also be provided that the supply unit additionally includes a means for measuring the flow rate or the quantity of concentrate conveyed. In addition, the supply unit can have one or more check valves to only allow the concentrate flow in one direction. This allows the Damage to some sensitive components can be prevented, and dilution of the concentrate in the concentrate container by the fresh water present in the supply unit can be avoided. This is particularly preferred because the system requires a constant concentration of the concentrate in the concentrate container and dilution should therefore be avoided if possible.

Preferably, the supply unit comprises at least one check valve to allow water flow in only one direction and at least one check valve to allow concentrate flow in only one direction. If the supply unit is set up to be connected to a pressurized line, a check valve is preferably arranged between the water inlet and a flow meter. If the supply unit is set up to convey water and/or concentrate by means of a volumetric pump, a check valve is preferably arranged in the flow direction behind the volumetric pump and a flow meter, but in front of the point at which water and concentrate mix.

Preferably, to provide fresh cooling lubricant emulsion, the concentrate is conveyed from the concentrate container via a concentrate suction line with a riser pipe, wherein a filling level of the concentrate in the concentrate container is determined by introducing compressed air into the concentrate suction line, wherein an air pressure in the concentrate suction line is measured with a pressure sensor, a limit pressure for a pressure increase is determined and the filling level in the concentrate storage container is calculated using the limit pressure.

Other suitable level sensors that can be used to determine the fill level include floats or ultrasound-based sensors. Furthermore, sensors based on TDR technology (Time Domain Reflectometry) can be used.

The provision unit can further comprise a mixer. The supply unit preferably comprises a static mixer for mixing water and concentrate. The mixer achieves good mixing of the conveyed concentrate with the water, so that a homogeneous emulsion is provided. Optionally, it can be provided that the supply unit is additionally set up to add additives to the fresh cooling lubricant emulsion in order to change its properties as required. For this purpose, the additives can, for example, be conveyed from an additive container in a similar way to how the concentrate is conveyed from the concentrate container. In this case, the additive is preferably added to the fresh cooling lubricant emulsion in the mixer for mixing water and concentrate.

Furthermore, it is provided that the provision unit comprises an outlet through which the fresh cooling lubricant emulsion provided is conveyed out of the provision unit. The outlet can, for example, be used as a connection to a line, e.g. B. a pipe or a hose.

The outlet is designed to be connected to the distribution unit to enable fluid exchange with it.

The provision unit can also include further components. For example, it is provided that the supply unit can be controlled by the control unit in order to determine and/or change the amount of water and concentrate delivered. For this purpose, the provision unit can have at least one interface via which communication with the control unit is enabled. This is typically connected to the components of the provision unit via an electronic circuit to enable their control. Furthermore, firmware is typically installed to control the components.

Such an interface can be any interface that enables data transmission, for example an interface for a data cable via which the provision unit can be connected to the control unit, or a wireless interface that enables a wireless data connection (ie via electromagnetic waves) to the control unit. The provision unit preferably comprises a wireless interface. Suitable wireless interfaces can be, for example, interfaces for communication via a Bluetooth® connection, a wireless local area network (WLAN), a wireless personal area network (WPAN), optical radio link, mobile radio, infrared technology, radio technology or the like. The wireless interface is preferably, for example, a Bluetooth® interface, a WLAN interface or a Mobile phone interface. The measuring unit can also have additional interfaces in order to be able to establish a direct connection to other components of the system, for example to the fill level sensor for determining the fill level in the concentrate container.

The supply unit can also be supplied with power in any way. For example, the supply unit can comprise an AC connection, a DC connection, a battery compartment and/or a permanently installed rechargeable battery. An AC connection or a DC connection are preferred because they enable continuous and automated operation without the need for regular battery replacement or regular charging of the permanently installed battery. In the case of an AC connection, the supply unit can also comprise an AC/DC converter in order to be able to supply parts of the supply unit that are operated with DC.

The measuring unit of the system according to the invention comprises at least one sensor for determining at least one parameter of a coolant-lubricant emulsion. Cooling lubricant emulsion can be passed past the at least one sensor in the measuring unit.

The at least one sensor is preferably selected from the group comprising pH sensors, conductivity sensors, photometers, light barriers and refractometers.

A refractometer and other sensors used in connection with the device are described, for example, in WO 2020/126257.

Furthermore, it is provided that the measuring unit has an inlet through which liquids such as cooling lubricant emulsion can enter the measuring unit, and has an outlet through which the liquids can exit the measuring unit again. At least the inlet is set up to be connected to the distribution unit of the system in order to enable fluid exchange between the distribution unit and the measuring unit. Preferably, the outlet is also set up for this purpose to be connected to the distribution unit. The measuring unit can also include other components. For example, it is provided that the measuring unit can be controlled by the control unit in order to carry out the measurement of at least one parameter of a cooling-lubricant emulsion and to transmit the measurement data to the control unit. For this purpose, the measuring unit can have at least one interface via which communication with the control unit is enabled. This is typically connected to the components of the measuring unit via an electronic circuit to enable their control. Furthermore, firmware is typically installed to control the components.

Suitable and preferred interfaces have already been described for the provision unit and are also suitable or preferred for the measuring unit. The measuring unit preferably includes a wireless interface for communication with the control unit.

Furthermore, the measuring unit can have further interfaces in order, for example, to be able to establish a direct connection to other components of the system, for example to the distribution unit.

The measuring unit can also be supplied with electricity in any way. Suitable and preferred types of power supply have already been described for the provision unit and are also suitable or preferred for the measuring unit.

The measuring unit is typically set up to receive cooling lubricant emulsion from the distribution unit, measure at least one parameter of the cooling lubricant emulsion using the at least one sensor, transmit the measurement data to the control unit and return the cooling lubricant emulsion to the distribution unit or directly into a tank to give away. The measuring unit is preferably set up to return the cooling-lubricant emulsion to the distribution unit after a measurement.

The distribution unit of the system according to the invention is designed to be connected to the measuring unit, the supply unit and a tank and to regulate the exchange of cooling lubricant emulsion between them. For this purpose, the distribution unit can be provided with several inlets and outlets for cooling lubricant emulsion, which can be designed, for example, as connections to lines such as pipes or hoses.

In particular, the distribution unit may comprise the following types of connections:

A) a connector adapted to be connected to the outlet of the supply unit;

B) at least one connection adapted to be connected to a tank for cooling lubricant emulsion;

C) a connector adapted to be connected to the inlet of the measuring unit;

D) optionally a port that is adapted to be connected to the outlet of the measuring unit;

E) optionally one or more additional connections, for example to enable partial disposal of cooling lubricant emulsion.

Some of these connections can function as unidirectional inlets or unidirectional outlets, and some can function as bidirectional inlets and outlets. The connection of the distribution unit that is designed to be connected to the inlet of the measuring unit preferably functions as a unidirectional outlet. The connections of the distribution unit that are designed to be connected to the outlets of the supply unit or the measuring unit preferably function as unidirectional inlets. The connections of the distribution unit that are designed to be connected to a tank can, depending on the design of the distribution unit, preferably function as unidirectional inlets or outlets or as bidirectional inlets and outlets.

Furthermore, it can be provided that the distribution unit comprises at least one volumetric pump that is designed to convey cooling lubricant emulsion from a tank into the distribution unit. Alternatively or additionally, the distribution unit can comprise at least one controllable pump and a flow meter assigned to the pump, with which a volume conveyed by the pump is determined. Alternatively, it can be provided that a volumetric pump or a controllable pump with a flow meter assigned to the pump are present as external components and are connected to the distribution unit. Furthermore, it can be provided that the distribution unit comprises further flow meters which, for example, measure the volume of cooling lubricant emulsion which enters the distribution unit from the supply unit and/or the measuring unit, and/or is conveyed from the distribution unit into the measuring unit or a tank, and/or is led out of the distribution unit to be disposed of.

Preferably, the distribution unit of the system according to the invention is designed to be connected to a tank via at least one intake line. The intake line preferably comprises a solids filter, for example a chip filter, which prevents solids from the tank from entering the intake line and the distribution unit.

The characteristics of suitable pumps and flow meters have already been described for the supply unit and are also applicable to the distribution unit.

It is preferably provided that the distribution unit comprises further valves with which the flow of fresh cooling-lubricant emulsion or of cooling-lubricant emulsion removed from a tank between the supply unit, the measuring unit and a tank is regulated.

The distribution unit can have at least one check valve to allow the flow of cooling lubricant emulsion in only one direction. For example, a check valve can be used to define the function of a connection of the distribution unit as a unidirectional inlet or outlet. In this case, check valves are preferably arranged directly behind the respective inlet or outlet in the distribution unit. Furthermore, this can prevent damage to some sensitive components and, for example, avoid contamination of the fresh cooling lubricant emulsion with the cooling lubricant emulsion removed from a tank.

The distribution unit can also include other components. For example, it is provided that the distribution unit can be controlled by the control unit in order to regulate the exchange of liquid between the supply unit, the measuring unit and a tank. For this purpose, the distribution unit can have at least one interface via which a Communication with the control unit is enabled. This is typically connected to the components of the distribution unit via an electronic circuit to enable their control. Furthermore, firmware is typically installed to control the components. Suitable interfaces have already been described for the provision unit and are also suitable for the distribution unit.

The distribution unit preferably comprises an interface for a data cable, which is set up to be connected to an interface of the measuring unit via a data cable. In this case, communication with the control unit takes place via the connection to the measuring unit, and via the interface of the measuring unit, which is set up to be connected to the control unit. Alternatively, the distribution unit can be connected directly to the control unit, for example via its own wireless interface or via a cable.

The distribution unit can also be supplied with electricity in any way. Suitable types of power supply have already been described for the provision unit and are also suitable for the distribution unit. The distribution unit is preferably supplied via a power connection that is set up to be connected to the power supply of the measuring unit. More preferably, the power connection is built into the interface of the distribution unit for a data cable, which is set up to be connected to an interface of the measuring unit, and this interface of the measuring unit and the data cable are set up to supply the distribution unit with power, preferably direct current.

The fill level sensor of the system according to the invention, which is set up to measure the fill level in a tank, can be designed, for example, as a float or as an ultrasound-based sensor. Furthermore, sensors based on TDR technology (Time Domain Reflectometry) can be used. Fill level sensors, in which the fill level is determined by introducing compressed air into a line leading to the tank, an air pressure in the line is measured with a pressure sensor, a limit pressure for a pressure increase is determined and the fill level in the tank is calculated using the limit pressure, can also be used be used. The fill level sensor is preferably an ultrasound-based sensor. It is preferably provided that the fill level sensor is installed in the distribution unit, and the distribution unit is set up to be attached to a tank in order to be able to measure the fill level in the tank.

Furthermore, the system can include a sensor for detecting the formation of foam. This is preferably also installed in the distribution unit.

The control unit of the system according to the invention can be any type of control unit that can be connected to the provision unit, the measuring unit and the distribution unit and can control these or the components installed therein. The control unit is preferably a computer. The control unit can also comprise several interconnected devices, for example one or more computers that can be connected to one another via a network (e.g. local network, wireless local network, mobile network).

It is envisaged that the control unit includes interfaces via which it can be connected to the interfaces of the provision unit, the measuring unit and the distribution unit and can communicate with them. For example, the control unit comprises at least one wireless interface, if at least one selected from the provision unit, the measuring unit and the distribution unit has a wireless interface, and at least one interface for a data cable, if at least one selected from the provision unit, the measuring unit and the distribution unit has a corresponding one Has interface.

The control unit can also be supplied with power in any way. Suitable and preferred types of power supply have already been described for the provision unit and are also suitable or preferred for the control unit.

Preferably, the provision unit, the measuring unit and the control unit each have a wireless interface, the measuring unit and the distribution unit each having an interface for a data cable, the provision unit and the measuring unit being set up to be connected to the control unit via the wireless interfaces, and wherein the distribution unit is set up with the measuring unit to be connected via the interfaces for a data cable, and wherein the control unit is set up, to communicate with the provisioning unit and the measuring unit via the wireless interfaces, and to communicate with the distribution unit via the wireless interface of the measuring unit and the data cable.

It is intended that the fluid exchange between the supply unit and the distribution unit, between the distribution unit and the measuring unit and between the distribution unit and a tank takes place via external lines such as pipes or hoses.

According to the invention, the term "line" refers to devices intended for the passive transport of flowable materials, e.g. liquids, gases, dispersions and free-flowing solids, in particular hose lines and pipelines. Unless explicitly stated in the respective context, "line" does not refer to power lines or data lines.

The term "internal line" refers to a line that serves to transport flowable materials within a component of the system (e.g., supply unit, distribution unit, measuring unit). The term "external line" refers to a line that serves to transport flowable materials outside a component of the system (e.g., between the components of the system).

External lines can, for example, be designed to be reversibly or irreversibly connected to the supply unit, the distribution unit and/or the measuring unit.

In this context, "reversible" means that repeated non-destructive (except for wear damage) separation and restoration of the connection is possible. "Irreversible" means that non-destructive separation and restoration of the connection is not possible.

Irreversible connections can have the advantage that the liquid-tightness of the connections is higher and the wear is lower than with reversible connections, but at the same time they have the disadvantage that separating the connections, e.g. to replace the individual components, is only possible with greater effort. Irreversible Connections can be made, for example, by welding lines to connections or inlets and outlets of the supply unit, the distribution unit and/or the measuring unit.

Reversible connections, on the other hand, have the advantage that the connections can be repeatedly separated and reestablished, so that, for example, individual components can be quickly replaced if necessary (e.g. for maintenance). Suitable means for producing reversible connections are, for example, quick-release connections, threaded connections, magnetic connections, adhesive connections, clamps, clamps, sleeves and clamps.

Quick-release fasteners are preferred here, as they can often withstand high pressures, but can be separated quickly if necessary. At the same time, quick-release fasteners are often designed in such a way that if the connection is separated, a valve in the fastener closes so that no liquid can escape from the line.

It is preferably provided that the system according to the invention comprises at least one line for fresh cooling lubricant emulsion, which enables a reversible connection between the supply unit and the distribution unit.

In these cases, it is preferred that the respective line has at least one free end, wherein the at least one free end has an identification feature that is uniquely assigned to the line, and wherein the at least one free end is set up to be reversibly connected to the supply unit, the distribution unit or both to be, preferably via a quick-release fastener, and wherein the distribution unit, the provision unit or both are set up to recognize the identification feature when a connection is established with the at least one free end.

The identification feature may be any identification feature that can be uniquely assigned and recognized by electronic means. For example, the identification feature may be a near-field or radio frequency identification transponder (NFC or RFID transponder), a printed code (barcode, QR code, serial number and similar), or a coded contact field. Accordingly, the provision unit and/or the distribution unit can have a means for reading the corresponding identification feature, such as an NFC or RFID reader for reading the NFC or RFID transponder, a scanner for reading the printed code, or a reader for the coded contact field. Preferably, the identification feature is an NFC or RFID transponder, preferably an RFID transponder, and the reader is an NFC or RFID reader, preferably an RFID reader, since these have the advantage that no prescribed alignment of the transponder and the reader is required to enable recognition of the identification feature, and the spatial proximity of the identification feature to the reader can be sufficient.

Here, one end of the line can be irreversibly connected to the provision unit and the other end can be the free end and can be set up to be reversibly connected to the distribution unit, the distribution unit being set up to recognize the identification feature. In this case, the identification feature is also uniquely assigned to the provision unit. The distribution unit is set up to determine the establishment of a connection (e.g. quick-release connection) between the free end of the line and the connection of the distribution unit provided for this purpose (e.g. by closing an electrical contact in the connection), to recognize the identification feature on the free end, and the to transmit recognized data to the control unit. The control unit is set up to assign the identification feature to the line and the provision unit (e.g. based on a stored database) and to establish a data connection to the identified provision unit and to the distribution unit.

Alternatively, one end of the line can be irreversibly connected to the distribution unit and the other end can be the free end and can be set up to be reversibly connected to the provision unit, the provision unit being set up to recognize the identification feature. In this case, the identification feature is also uniquely assigned to the distribution unit. The provision unit is set up to determine the establishment of a connection (e.g. quick-release connection) between the free end of the line and the connection of the provision unit provided for this purpose (e.g. by closing an electrical contact in the connection). To recognize identification feature at the free end and to transmit the recognized data to the control unit.

The control unit is configured to assign the identification feature to the line and the distribution unit (e.g. based on a stored database) and to establish a data connection to the identified distribution unit and to the provision unit.

Alternatively, both ends of the line can be free ends, with one free end being set up to be reversibly connected to the distribution unit and the other free end being set up to be reversibly connected to the provision unit, and wherein the provision unit and the distribution unit are set up, to recognize the identification features on the free ends.

The provision unit and the distribution unit are designed to detect the establishment of a connection (e.g. quick-release connection) between the free end of the line and the connection provided for this purpose on the provision unit or the distribution unit (e.g. by closing an electrical contact in the connection), to detect the identification feature on the free end and to transmit the detected data to the control unit. The control unit is designed to assign the identification feature detected by the provision unit and the identification feature detected by the distribution unit to a line (e.g. using a stored database), to compare the identified lines with one another and, if there is a match, to establish a data connection to the provision unit and to the distribution unit.

In these configurations, it is possible for the control unit to clearly identify whether there is a connection between the supply unit and the distribution unit through which a fluid exchange can take place. It is also possible for the control unit to clearly identify which distribution unit is connected to which supply unit if several distribution units and/or supply units are available for selection, and to control these accordingly so that the method according to the invention can be carried out with them. In addition, the system according to the invention can comprise lines for cooling lubricant emulsion, which enable reversible connections between the measuring unit and the distribution unit and/or between the distribution unit and a tank. In these cases, the reversible connections can be set up in the same way as described above for the reversible connection between the supply unit and the distribution unit.

The system according to the invention can also be set up for the conditioning of coolant-lubricant emulsion in several tanks for several machine tools. For this purpose, it is provided that the system comprises at least one second measuring unit, at least one second distribution unit and at least one second level sensor, the second level sensor being set up to measure the level in a second tank, the provision unit also being spatially separated from the second measuring unit and is not in direct fluid exchange with it, and wherein the second distribution unit is set up to be connected to the second measuring unit, the supply unit and the second tank, and to regulate the exchange of cooling lubricant emulsion between them, and the system is set up, to condition the cooling lubricant emulsions in at least two tanks, and wherein the control unit is set up to determine through which distribution unit the fresh cooling lubricant emulsion is led out of the supply unit.

This has the advantage that in the method according to the invention with a supply unit, the cooling-lubricant emulsion can be conditioned in several tanks, which can be done in an automated process. For this purpose, it is provided that each tank is connected to a separate distribution unit, and each distribution unit is connected to a separate measuring unit, but several distribution units are connected to the same supply unit.

The description of the distribution unit, the measuring unit, the level sensor and their connections to the provision unit and the control unit as well as to each other applies accordingly to the second distribution unit, the second measuring unit, the second level sensor and their connections to the provision unit and the control unit as well as to each other. The system according to the invention can be set up to condition a cooling lubricant emulsion in a single tank for a machine tool. The supply unit is connected via a line to a single distribution unit, which is in fluid exchange with a single tank. This can be useful, for example, in companies in which there is only a single machine tool with a single tank, and expansion to additional machine tools is not planned, for example because there is no spatial capacity for additional machine tools.

Alternatively, the system according to the invention is set up to condition a coolant-lubricant emulsion in at least two tanks for machine tools, it being provided that the supply unit is connected to all distribution units at the same time via a branched line and is in fluid exchange with them. In this case, the control unit is set up to carry out the following steps: a1) Controlling the supply unit so that it mixes an amount of concentrate defined for a selected one of the at least two tanks with an amount of water defined for the selected one of the at least two tanks and the mixture as fresh providing cooling lubricant emulsion; b1 ) Controlling the distribution unit that is connected to a selected tank so that it leads fresh cooling lubricant emulsion from the supply unit into the measuring unit connected to this distribution unit or into the selected tank, or cooling lubricant emulsion from the selected tank into the one connected to this distribution unit connected measuring unit, and / or optionally leads at least part of the cooling-lubricant emulsion from this measuring unit into the selected tank; c1 ) Receiving measurement data from the sensors of all measuring units and from all level sensors; d1) Calculating the follow-up quantity required to transfer the fill level in a selected tank from a measured actual fill level to a defined target fill level; e1) Calculating the follow-up concentration of a fresh coolant lubricant emulsion, which is required for a calculated follow-up quantity in order to convert the measured actual concentration in a selected tank into a defined target concentration. f1 ) Selecting a tank in which the cooling lubricant emulsion is to be conditioned. The selection of the tank can be done automatically, for example the control unit can use received measurement data to check whether the fill level or concentration in all tanks is in a predetermined range, and select a tank if the fill level or concentration is not in the predetermined range lies.

The flow of fresh cooling lubricant emulsion only into the distribution unit connected to the selected tank can be generated, for example, by opening valves in the selected distribution unit and closing them in all other distribution units. Alternatively, the system can further comprise a distribution block with valves, which is installed in the branched line between the supply unit and the distribution units and, by opening and closing the valves, determines the branch of the line through which the cooling lubricant emulsion is conveyed.

In this case, the distribution block is controlled by the control unit, whereby the data connection between the distribution block and the control unit can be established via a direct (e.g. wireless) interface, or via the interface of the provision unit, whereby the distribution block is connected to the provision unit via a data cable is.

This can be useful, for example, in companies where there are several machine tools with several tanks and they are in close proximity to one another.

Alternatively, the system according to the invention is set up to condition a coolant-lubricant emulsion in at least two tanks for machine tools, it being provided that the supply unit can be connected to several distribution units via a reversible line, the line having at least one free end, the at least a free end has an identification feature that is clearly assigned to the line. The at least one free end is set up to be reversibly connected to the provision unit, the distribution unit or both, preferably via a quick-release fastener, and the distribution unit, the provision unit or both are set up to use the identification feature when a connection is established with the at least one free end recognize.

In this case, the control unit is set up to carry out the following steps: a2) Controlling the supply unit so that it mixes a defined amount of a concentrate with a defined amount of water and provides the mixture as a fresh cooling lubricant emulsion, the amount of concentrate and the amount of water being defined for the tank that is connected to an identified distribution unit connected is; b2) Controlling the identified distribution unit so that it leads fresh cooling lubricant emulsion from the supply unit into the measuring unit connected to the distribution unit or into the tank connected to the distribution unit, or leads cooling lubricant emulsion from this tank into this measuring unit, and / or optionally at least leads part of the cooling lubricant emulsion from this measuring unit into this tank; c2) receiving measurement data from the sensors of all measuring units and from all level sensors; d2) Calculating the follow-up quantity required to transfer the fill level in the tank connected to the identified distribution unit from a measured actual fill level to a defined target fill level; e2) Calculating the follow-up concentration of a fresh coolant lubricant emulsion, which is required for a calculated follow-up quantity in order to convert the measured actual concentration in the tank connected to the identified distribution unit into a defined target concentration. f2) Identify the distribution unit to which the provisioning unit is connected.

The selection of the tank in which the cooling lubricant emulsion is to be conditioned is done manually by a user. For example, the control unit can use received measurement data to check whether the fill level or concentration in all tanks is within a specified range and issue a warning to the user if this does not apply to a tank. The user may then be asked to connect the delivery unit to the distribution unit connected to that tank.

It is preferred that the reversible line between the supply unit and the distribution unit is a hose made of a flexible but corrosion-resistant material, as this makes it easier to connect and disconnect the supply unit from different distribution units. This can be useful, for example, in companies where there are several machine tools with several tanks, but these are not in spatial proximity to one another. The supply unit can be placed together with a concentrate container and, if necessary, a water container, for example on a mobile means of transport (e.g. a trolley), and can be moved between the various tanks using the means of transport in order to be connected to the corresponding distribution units.

Preferably, the supply unit is therefore designed to be reversibly connected to the distribution unit and, at least in the separated state, to be moved independently of the measuring unit, the distribution unit and the tank.

In particular, it is advantageous if the control unit communicates with the provision unit, the measuring units and the distribution units via wireless interfaces, since in this case the control often takes place over a large distance.

Alternatively, a group of distribution units, each connected to a measuring unit and a tank, can also have a common line that has a free end with an identification feature that is designed to be reversibly connected to the supply unit. In this case, the control unit can be designed to carry out steps a1) to f1) as described above when establishing a connection to this group of distribution units.

This can be useful, for example, in companies where there are several groups of machine tools with several tanks located in close proximity, with the individual groups and, if necessary, individual additional machine tools with tanks located in different rooms.

Particularly in embodiments of the system that are designed to be connected to multiple tanks, it is preferable to take measures to avoid mixing of different cooling lubricant emulsions. Therefore, a compressed air line is preferably provided, which is connected via a compressed air valve to the lines between the supply unit and the distribution units, or to the supply unit, so that cooling lubricant emulsion present in the lines can be blown out. The compressed air introduced via the compressed air line forces any cooling lubricant emulsion present through the respective distribution unit into the respective tank. This is particularly advantageous because it also blows out and cleans chip filters located in the connection between a distribution unit and a tank, which prevent chips and particles from entering the measuring circuit. As an alternative to cleaning with compressed air, or in addition to this, lines can also be cleaned using pigs.

In addition to blowing out the tanks for cleaning purposes, the compressed air line can also be used to ventilate the tanks for longer periods.

In this way, the formation of bad odours can be prevented, especially during long periods of storage, by preventing an anaerobic state of the emulsion due to the introduction of oxygen.

Furthermore, in embodiments with multiple tanks, it is provided that the system is set up to monitor the at least one parameter of the cooling lubricant emulsion and the fill level even in the tanks that are not in fluid exchange with the supply unit.

A further subject of the invention is a method for conditioning a cooling lubricant emulsion for machine tools, wherein a cooling lubricant emulsion is provided in a tank and wherein the cooling lubricant emulsion is removed from the tank, using at least one sensor to determine at least one parameter of the cooling Lubricant emulsion is detected, from which at least one parameter the concentration of the cooling lubricant emulsion in the tank (60) is determined, and the cooling lubricant emulsion is at least partially returned to the tank, and the level in the tank is measured using a level sensor, a the required follow-up concentration and follow-up amount is calculated and the fresh cooling lubricant emulsion with the calculated follow-up concentration is provided in the calculated follow-up quantity, further comprising the step: calibrating the at least one sensor, by flushing the at least one sensor and carrying out a measurement with fresh cooling lubricant emulsion, which has a defined ratio of concentrate to water, the fresh cooling lubricant emulsion being provided by a supply unit, the sensor being part of a measuring unit, the provision unit is spatially separated from the measuring unit and is not in direct fluid exchange with the measuring unit, and the provision unit, the measuring unit and the tank are connected to a distribution unit which regulates the exchange of cooling-lubricant emulsion between them, and whereby the Method is controlled by a control unit.

The method according to the invention is preferably carried out using the system according to the invention, as described above.

In the method, a cooling lubricant emulsion is preferably provided in a respective tank for at least two machine tools, each of the tanks being connected to a distribution unit which is connected to a measuring unit, the fresh cooling lubricant emulsion being provided in a common provision unit and wherein the exchange of the cooling-lubricant emulsion between the supply unit and the distribution units is controlled manually by changing the distribution unit connected to the supply unit or automatically by the control unit.

Except in cases where the exchange is controlled manually by changing the distribution unit connected to the delivery unit, the process is preferably fully automated.

In the present context, “fully automated” means that a user only defines the start and end of the process, as well as, if applicable, target values and tolerance ranges for the fill levels, the concentrations and/or at least one parameter of the cooling lubricant emulsion in the tank, and only has to intervene in the process if an error is detected.

The at least one parameter can be, for example, a refractive index, a pH value, an electrical conductivity, a light transmittance or a degree of reflection of the cooling lubricant. Furthermore, combinations of at least two of these parameters can be measured within the scope of the method. Further properties can be determined from the at least one parameter determined in a measurement in which one or more measuring reagents are used if necessary. Derived properties of the cooling lubricant emulsion can in particular be selected from a concentration of the cooling lubricant emulsion, a total amine / total acid value (TA/TS value), a buffer capacity, a metal content, an oil content and a nitrite content. For example, to determine the derived properties, the method may additionally comprise the following step:

Carrying out a measurement in which a sample is taken from the tank, the sample is continuously guided past the at least one sensor in a circuit in order to record at least one parameter of the sample, wherein at least one measuring reagent is added continuously or step by step and the at least one parameter is continuously measured until the at least one parameter reaches a predetermined threshold value, and then at least part of the sample is fed back into the tank. For this purpose, the distribution unit can, for example, comprise further connections through which a measuring reagent can be added.

A reliable measurement of the concentration of the cooling lubricant emulsion in the tank is necessary, particularly for calculating the follow-up concentration. The refractive index of the cooling lubricant emulsion is usually measured with a refractometer to determine the concentration of the cooling lubricant emulsion. A refractometer determines the refractive index at the interface between a transparent surface and the cooling lubricant emulsion. A major problem here is the formation of oily deposits (oil films) from the oil-containing cooling lubricant emulsions on the measuring window.

These deposits cause a gradual increase in the measured value and suggest that the concentration of the cooling lubricant emulsion in the tank is too high. This, in turn, leads to incorrect calculation of the concentration of the fresh cooling lubricant emulsion provided for the follow-up, which in particular is chosen to be too low.

This in turn results in the concentration of the coolant-lubricant emulsion in the tank being lower than intended, causing problems such as reduced cutting performance, increased tool wear, corrosion and susceptibility to microbiological attack. Since the faulty measurement of the refractometer occurs gradually, it is difficult to detect. A control measurement is usually carried out with a second refractometer. Alternatively, a calibration solution can be added to the measuring system to check the measuring accuracy of the refractometer. The calibration solutions used usually have to be removed from the system and disposed of. A simple, waste-free process with which the contamination level of the refractometer can be determined at any time would be desirable.

According to the invention, the method therefore provides for rinsing the at least one sensor with fresh cooling lubricant emulsion and then carrying out a measurement of the at least one parameter of this fresh cooling lubricant emulsion using this sensor. Since the fresh cooling lubricant emulsion has a defined ratio of a concentrate to water, its properties are known, so that the measured value obtained for the at least one parameter of the cooling lubricant emulsion can be compared with a predetermined target value.

Preferably, the cooling lubricant emulsion used for calibration can be used to condition the cooling lubricant emulsion contained in the tank instead of discarding it. Accordingly, it is preferably provided that the cooling-lubricant emulsion used for calibration is fed into the tank after the measurement.

By comparing the measured value for the at least one parameter of the fresh cooling lubricant emulsion with the predetermined target value, the at least one sensor can be calibrated. For this purpose, for example, a correction factor can be determined with which measured values of the at least one sensor are corrected. If calibration is not possible or a deviation between the measured value and the target value is greater than a specified limit, a warning message can also be issued to indicate that the sensor needs to be serviced or replaced.

For example, the refractive index of a fresh cooling lubricant emulsion with a precisely defined ratio of water to concentrate is known, so that this emulsion can be used to calibrate a refractometer. In contrast to a coolant lubricant emulsion different from the coolant lubricant emulsion, The cooling lubricant emulsion can then be fed into the tank using the calibration fluid, so that no waste is generated. There is also no need to keep a separate calibration fluid and/or a separate cleaning fluid in stock.

The fresh cooling lubricant emulsion provided for calibration has a known concentrate to water ratio. However, this ratio depends on the currently measured concentration of the coolant lubricant emulsion. The suggested calibration is preferably carried out whenever the cooling lubricant emulsion has to be added to the tank.

Accordingly, a fresh cooling lubricant emulsion is always used for calibration, the concentration of which is known, but usually has a different value for each calibration process. The sensor can therefore be calibrated using different cooling lubricant emulsions as test fluid, whereby the properties of these different cooling lubricant emulsions are known in each case. This makes it possible in particular to distinguish between a reduced sensitivity of the sensor and a shift in the zero point of the sensor.

Typically, the fresh coolant-lubricant emulsion provided for calibration and for re-running the tank contains an oil content in the range of 0% to 10%, whereby a different concentration is usually set in the fresh coolant-lubricant emulsion for each re-run due to the dependence on the concentration measured in the tank. An oil content in the range of 0% to 10% is optimal for calibration, as at these concentrations no permanent oil film remains on the sensor.

In addition to the refractive index, other parameters are preferably determined to describe the proper condition of the cooling-lubricant emulsion. The pH value, buffer capacity and conductivity are particularly important. Measuring electrodes are preferably used to measure the pH value and conductivity. Like the refractometer described above, these measuring electrodes also tend to become oily. The measured values change gradually, which leads to unwanted and difficult to detect incorrect measurements. Here too, rinsing and/or calibrating is preferred Using a fresh cooling lubricant emulsion with a defined concentration.

The fresh cooling lubricant emulsion with the defined concentration or the defined ratio of concentrate to water is preferably obtained by pumping water and/or concentrate using a volumetric pump. Alternatively or additionally, the fresh cooling lubricant emulsion can be obtained by pumping concentrate and/or water with a controllable feed pump, whereby the pumped amount of water and/or concentrate is measured and the feed pump is controlled depending on the measured pumped quantity.

The production of fresh cooling lubricant emulsion with a defined concentration is preferably used not only for flushing and/or calibrating the at least one sensor, but always when fresh cooling lubricant emulsion is required for follow-up. Conversely, flushing and calibration of the at least one sensor is preferably carried out with fresh cooling lubricant emulsion with a defined concentration each time it is followed.

The defined concentration is preferably determined depending on the measured concentration of the cooling lubricant emulsion stored in the tank in such a way that when the fresh cooling lubricant emulsion is used with the amount required to fill the tank, a concentration of the cooling lubricant emulsion is established in the tank which is one Specification corresponds.

The concentration can be determined by the control unit, which first calculates the amount of replenishment required to fill the tank from the difference between a specified target fill level and the measured actual fill level in a tank, and from the difference between a specified target concentration and the measured actual concentration of the coolant lubricant emulsion and the required follow-up concentration is determined from the calculated required follow-up quantity.

Certain ingredients such as oils, surface-active additives, amines, fatty acids, corrosion inhibitors, performance additives, stabilizers and/or biocides are used when separating chips from the cooling system. Lubricant emulsion discharged disproportionately from the cooling lubricant emulsion. This causes the cooling lubricant emulsion to become depleted of these ingredients. This depletion of ingredients leads to quality losses such as a reduction in cutting performance or an increase in susceptibility to corrosion or microbial infestation.

The selective depletion of the cooling lubricant emulsion cannot be compensated by adding fresh cooling lubricant emulsion. Preferably, the depletion of a constituent can be determined from the at least one parameter of the cooling lubricant emulsion. If such depletion is detected, it is preferably provided to selectively replace the discharged components by adding additives.

In this case, conditioning of the cooling lubricant emulsion held in the tank can be carried out by removing the cooling lubricant emulsion from the tank, adding at least one additive to the cooling lubricant emulsion depending on the at least one parameter and returning the conditioned cooling lubricant emulsion to the tank. It is also possible to mix the cooling lubricant emulsion using a mixer before returning it to the tank.

For this purpose, the distribution unit can, for example, comprise additional connections through which an additive can be added. Alternatively, the supply unit can mix the additives into the fresh cooling lubricant emulsion in order to change its properties as required. For this purpose, the additives can, for example, be conveyed from one or more additive containers in a similar way to how the concentrate is conveyed from the concentrate container. In this case, the additive is preferably mixed into the fresh cooling lubricant emulsion in the mixer for mixing water and concentrate.

The additive is in particular selected from a component of the cooling lubricant emulsion such as a defoamer component such as polysiloxanes commonly used for defoaming, triisobutyl phosphate, wax defoamers or mineral oil-based defoamers, a hardening component such as a calcium and/or magnesium salt such as calcium acetate, magnesium acetate, calcium sulfonate, magnesium sisulfonate and their solutions, a corrosion-inhibiting component such as phosphoric or phosphonic acid esters and their salts, triazine derivatives and their salts, carboxylic acids, fatty acids, di- or multivalent carboxylic acids and their neutralization products, a non-ferrous metal inhibiting component such as triazole derivatives and their salts, an aluminum-inhibiting component such as silane derivatives such as tetraethyl orthosilicate or meta-silicate solutions, a biocide component such as butylbenzothiazolinone, sodium omadin solution, an oil component, an amine component, a buffer component or an emulsifier.

In the case of the additives mentioned, solutions in water, oil or other suitable solvents can also be used.

In addition, the supply unit can meter in undiluted concentrate of the cooling lubricant emulsion if it is determined that the concentration of the cooling lubricant emulsion in the tank is too low and the filling level in the tank is high.

For reliable operation, it is desirable to be able to detect early on if a concentrate container, and possibly a water container and/or an additive container, is running empty. It is therefore preferred that in the method a measurement of a filling level of the concentrate in the concentrate container and, if appropriate, of the water in the water container and/or of the additive in the additive container is carried out. If the filling level falls below a predetermined minimum level, a message can be issued, for example, requesting that the respective container be changed or refilled. Furthermore, it can be provided, for example, that when an empty container is detected, a switch-off occurs or a switch is made to another container, or the respective container is refilled.

The method according to the invention preferably comprises the following steps: aa) providing a fresh cooling-lubricating emulsion, which has a defined ratio of a concentrate to water, in the provision unit; bb) introducing the fresh cooling-lubricating emulsion from the provision unit into the measuring unit by means of the distribution unit; cc) Calibrating the at least one sensor of the measuring unit with the fresh cooling lubricant emulsion fed into the measuring unit by carrying out a measurement with the fresh cooling lubricant emulsion, which has a defined ratio of a concentrate to water, wherein optionally the fresh cooling lubricant emulsion is at least partially fed into the tank after the measurement; dd) Taking cooling lubricant emulsion from a tank and introducing the cooling lubricant emulsion into the measuring unit using the distribution unit; ee) Measuring the at least one parameter of the cooling lubricant emulsion with the at least one sensor of the measuring unit in order to determine the actual concentration of the cooling lubricant emulsion in the tank based on the at least one parameter, wherein optionally the cooling lubricant emulsion is at least partially fed back into the tank; ff) Measuring the fill level in the tank with the fill level sensor; gg) Calculating the follow-up quantity that is required to reach a predetermined fill level in the tank; hh) Calculating the follow-up concentration that is calculated for the

refill quantity is required to condition the concentration of the cooling lubricant emulsion in the tank to a specified target value; ii) providing a fresh cooling lubricant emulsion having the calculated required refill concentration in the calculated refill quantity using the supply unit; jj) introducing the fresh cooling lubricant emulsion into the tank using the distribution unit to condition the cooling lubricant emulsion in the tank.

If the cooling-lubricating emulsion is to be conditioned in several tanks, the method may additionally comprise the step; kk) changing the distribution unit, the measuring unit and the tank into which fresh cooling-lubricating emulsion is fed from the supply unit, and repeating steps aa) to jj).

Furthermore, steps dd) to jj) can be repeated for each tank so that the cooling lubricant emulsion is conditioned continuously or at regular intervals. Likewise, steps aa) to cc) can be repeated for each measuring unit so that the calibration of the sensors is carried out at regular intervals. Since the method according to the invention is controlled by the control unit and preferably runs automatically, it can be provided in particular that in the method a target concentration of the cooling lubricant emulsion in a tank, a tolerance range for the concentration around the target concentration, a target fill level in the tank and a tolerance range for the fill level around the target fill level are defined, and the method is carried out automatically by the control unit with these defined values.

The target concentration is the desired concentration of the cooling lubricant emulsion in a tank. This can be found, for example, in the operating instructions for a machine tool or in data sheets for the concentrates, in which the optimal concentrations can be specified.

The target fill level is the desired fill level in the tank for coolant and lubricant emulsion. This is usually a fill level at which the tank is considered full without there being any risk of the coolant and lubricant emulsion leaking out due to minor fluctuations in the fill level. This can be found in the tank's operating instructions, for example, or is marked on the tank.

The tolerance ranges are the concentration and fill level ranges in which the machine tool can be operated without concerns, or recommended ranges. These can arise, for example, from operating instructions for the machine tool or tank or from data sheets for the concentrates.

The target values and tolerance ranges can be determined by user input, for example by entering the values into designated fields of a user interface of the control unit via an input device (e.g. keyboard). Alternatively, the determination can be made automatically by the control unit reading the values from a database.

For automated operation, the control unit preferably carries out the following steps in the order given: i) Sending a request to the supply unit to start supplying fresh cooling lubricant emulsion with a Calibration defined ratio of concentrate to water, and sending a request to the distribution unit connected to the tank to start introducing the cooling-lubricant emulsion provided by the supply unit into the measuring unit connected to the distribution unit, wherein the cooling-lubricant emulsion from the measuring unit is optionally at least partially fed into the tank; ii) sending a request to the measuring unit to carry out a measurement of at least one parameter with the at least one sensor and to transmit the measurement data to the control unit in order to calibrate the at least one sensor; iii) sending a request to the supply unit to stop providing fresh cooling-lubricant emulsion and sending a request to the distribution unit to stop introducing the cooling-lubricant emulsion provided by the supply unit into the measuring unit; iv) sending a request to the distribution unit to start removing cooling-lubricant emulsion from the tank and introducing it into the measuring unit, wherein the cooling-lubricant emulsion from the measuring unit is at least partially returned to the tank; v) Sending a request to the measuring unit to carry out a measurement of at least one parameter with the at least one sensor and to transmit the measurement data to the control unit in order to determine the actual concentration of the cooling lubricant emulsion; vi) Sending a request to the distribution unit to stop removing the cooling lubricant emulsion from the tank and introducing it into the measuring unit; vii) Sending a request to the fill level sensor to measure the fill level in the tank and to transmit the measurement data to the control unit in order to determine the actual fill level in the tank; viii) Checking whether the determined actual fill level and the determined actual concentration are within the specified tolerance ranges; If yes: Repeat steps v) to viii); If no: Continue with step ix); (ix) calculating the required refill quantity from the difference between the specified target fill level and the determined actual fill level, and calculating the refill concentration required to achieve the target concentration at the calculated refill quantity based on the actual concentration; x) Sending a request to the supply unit to start supplying fresh cooling-lubricating emulsion with the calculated refill concentration and sending a request to the distribution unit to start introducing the cooling-lubricating emulsion provided by the supply unit into the tank in order to condition the cooling-lubricating emulsion in the tank; xi) When the target fill level is reached or the calculated refill quantity has been provided, sending a request to the supply unit to stop supplying fresh cooling-lubricating emulsion and sending a request to the distribution unit to stop introducing the cooling-lubricating emulsion provided by the supply unit into the tank.

Steps iv) to xi) are preferably repeated continuously or at intervals to check whether the actual concentration and the actual fill level are within the respective tolerance ranges and to correct them if necessary. Furthermore, steps i) to iii) are preferably repeated at intervals to check the calibration of the at least one sensor and to correct it if necessary. The steps are preferably repeated until a user input is made to end the process.

Furthermore, the control unit can preferably additionally carry out the following steps, which can be carried out regardless of the order specified above: xii) checking whether the requests sent are carried out correctly and issuing a warning if at least one request is not carried out; xiii) checking whether the level in the concentrate container and, if applicable, the water container and/or an additive container is sufficient, and issuing a warning if the respective container has a low level and needs to be replaced, or switching the supply unit to another container; xiv) Check whether a foam sensor detects significant foam formation and, if necessary, issue a warning signal that foam should be skimmed off or control the supply unit or the distribution unit to dose a defoamer into the tank. xv) Store and document concentrations, temperatures, fill levels, foam generation, water consumption, concentrate consumption, refill rates, control history and/or other data.

In embodiments where the connection between the provisioning unit and the distribution unit is reversible, the control unit may perform, among other things, the following additional steps: xvi) checking whether the reversible connection is established and issuing an alert if the reversible connection is disconnected; xvii) When establishing a connection to a line that has a free end with an identification feature, sending a request to the provisioning unit, distribution unit or measuring unit connected to the line to read the identification feature and identify the line, and assigning several connected to a line units as part of the same system; xviii) For multiple tanks, check that all levels and concentrations are within the respective tolerance range and issue a warning if a value is outside the tolerance range.

In embodiments in which multiple distribution units are connected to a provisioning unit, the control unit may, among other things, perform the following additional steps: xix) Check whether the valves of the uncontrolled distribution units are closed and, if necessary, send a request to these distribution units to the corresponding valves close; xx) When changing the controlled distribution unit, activate a compressed air valve so that cooling lubricant emulsion from a previous process is blown out of the line.

Advantages of the invention

Usually, in systems for monitoring cooling lubricant emulsions, the sensors have to be removed for calibration or a calibration fluid other than the cooling lubricant emulsion has to be added to the system to check the measuring accuracy of the sensors. Such a calibration fluid usually has to be removed from the system and disposed of, as it can have a detrimental effect on the properties of the cooling lubricant emulsion. The calibration proposed for the method according to the invention using a fresh cooling lubricant emulsion, on the other hand, represents a simple, waste-free process with which the contamination level of the sensors can be determined at any time. Furthermore, a fresh cooling lubricant emulsion with defined properties is provided, which can be used for calibrating at least one sensor. Here, too, the use of reference emulsions or calibration liquids is advantageously avoided, so that no waste is generated.

The proposed system enables simple and safe handling of cooling lubricant emulsions, whereby the condition of a cooling lubricant emulsion held in a tank can be monitored and, if necessary, conditioning can be carried out by adding additives. In particular, calibration and conditioning can be automated. This can lead to high time and cost savings, and the consumption of the cooling lubricant emulsion can be significantly reduced.

The spatial separation of the supply unit and the measuring unit, and the use of a distribution unit to regulate the fluid exchange between them and with a tank, as well as a control unit to control the components, enable significantly greater flexibility in the design of the system and in the implementation of the method than is the case with known methods. In particular, the use of the system according to the invention enables an operation in which several machine tools with several tanks can be operated using a supply unit, even if the tanks are not in close proximity to one another. Furthermore, in the event of maintenance, the individual units of the system according to the invention can be exchanged for other units of the same type without the operation of a machine tool having to be interrupted for a long period of time for the maintenance.

In addition, the automated process allows a significantly higher follow-up frequency, which means that the concentration in the tank can be kept essentially constant.

Short description of the characters Exemplary embodiments of the invention are shown in the drawings and explained in more detail in the following description. Show it:

FIG. 1 is a schematic representation of an embodiment of a provision unit of the system according to the invention,

FIG. 2 shows a schematic representation of another embodiment of a provision unit of the system according to the invention,

FIG. 3 is a schematic representation of an embodiment of a

Measuring unit of the system according to the invention,

FIG. 4 a schematic representation of an embodiment of one

Distribution unit of the system according to the invention,

FIG. 5 is a schematic representation of another embodiment of a distribution unit of the system according to the invention,

FIG.6 is a schematic representation of an embodiment of the system according to the invention with a tank and a concentrate container, the components of the system being connected to one another by lines,

FIG. 7 is a schematic representation of another embodiment of the system according to the invention for operating a single machine tool,

FIG. 8 is a schematic representation of a further embodiment of the system according to the invention for operating multiple machine tools, and

FIG. 9 is a schematic representation of a further embodiment of the system according to the invention for operating multiple machine tools using reversible connections,

FIG. 10 is a schematic representation of a combination of distribution unit and measuring unit of the system according to the invention, FIG. 11 is a schematic representation of another embodiment of the system according to the invention with a tank and a concentrate container using a combination of distribution unit and measuring unit.

In the following description of the exemplary embodiments of the invention, the same or similar components are designated with the same reference numerals, with a repeated description of these being omitted in individual cases. The figures represent the subject matter of the invention only schematically.

FIG. 1 shows a schematic representation of an embodiment of a supply unit 200 for providing fresh cooling-lubricating emulsion, which is designed to mix a defined amount of a concentrate with a defined amount of water and to provide the mixture as a fresh cooling-lubricating emulsion.

The supply unit 200 comprises a housing 201, an AC connection 202 which is designed to supply the supply unit with power, an AC-DC converter 203 in order to be able to supply the DC-operated components of the supply unit with DC, and an interface 204 which is designed as a wireless interface for data transmission between the supply unit 200 and a control unit. The interface 204 is connected to the electrically operated components of the supply unit via an electronic circuit (not shown) in order to enable their control. The supply unit 200 further comprises a fresh water connection 205 as a water inlet which can be connected to a fresh water line 216, and a concentrate connection 206 as a concentrate inlet which can be connected to a concentrate container via a line 217.

Furthermore, the supply unit 200 includes an outlet 207 for fresh coolant lubricant emulsion, to which an external line 218 for fresh coolant lubricant emulsion can be connected. An internal line leads from the fresh water connection 205 and the concentrate connection 206 into a static mixer 208, in which fresh water passed through can be mixed with concentrate passed through in order to produce fresh water To form cooling lubricant emulsion. An internal line leads from the static mixer 208 to the outlet 207 for fresh cooling lubricant emulsion.

The internal line that starts from the fresh water connection 205 contains a check valve 209 that is connected downstream of the fresh water connection 205 and only allows the flow of fresh water in the direction of the outlet 207 in order to avoid contamination of the fresh water by coolant-lubricant emulsion as far as possible. This internal line also contains a flow meter that is designed as a turbine 210 in this embodiment. When fresh water flows through, the turbine generates a measurable electrical current that can be converted by a control unit into a flow rate of the water flowing through the turbine. Behind the turbine 210, this internal line contains an electronically controllable valve 211, e.g. a solenoid valve, with which the flow rate of the fresh water can be regulated. Such a design of the line is particularly useful when the fresh water comes from a pressurized fresh water line, since in this case no active pumping of the fresh water is required, but the flow rate can be regulated by throttling via the controllable valve 211.

The internal line, which starts from the concentrate connection 206, contains a volumetric feed pump, which in this embodiment is designed as a gear pump 212, and a flow meter connected downstream of the volumetric pump, which in this embodiment is designed as an oval gear flow meter 213. In order to avoid contamination and/or dilution of the concentrate in a concentrate container by fresh water, the flow meter is followed by a check valve 214, which only allows the flow in the direction of the mixer 208. Furthermore, the provision unit 200 includes a fill level sensor 215 for determining the fill level in a concentrate container. The fill level in the concentrate container can be determined by introducing compressed air into the concentrate line 217, an air pressure in the concentrate line 217 being measured with a pressure sensor 219, a limit pressure for a pressure increase being determined and the filling level in the concentrate container being calculated using the limit pressure. In this embodiment, the fill level sensor 215 includes, in addition to the pressure sensor 219, a volumetric air pump 220 for generating the compressed air for introduction into the concentrate line 217. Alternatively, the supply unit 200 may include a compressed air connection for this purpose. The method for determining the fill level in the concentrate container is described in more detail, for example, in WO 2020/126257.

To provide the fresh cooling lubricant emulsion with this embodiment of the provision unit 200, the concentrate connection 206 and the fill level sensor 215 are connected to a concentrate container via the concentrate line 217, and the fresh water connection 205 is connected to a pressurized fresh water line. The controllable valve 211 is opened in such a way that a defined amount of fresh water can flow through. The turbine 210 is used to measure the amount of fresh water actually pumped. If necessary, the amount of fresh water delivered can be readjusted using the adjustable valve 211 until the defined amount of water flows through. Depending on the flow speed of the water, which is measured with the turbine 210, the gear pump 212 is controlled to pump a defined amount of concentrate from the concentrate container.

The actual amount of concentrate delivered is measured by the flow meter 213, and in case of deviations the gear pump 212 is controlled accordingly in order to adjust the amount of concentrate delivered to the defined amount.

The fill level sensor 215 measures the fill level in the concentrate container, and when the fill level is low, a signal can be sent to a control unit via the wireless interface 204 so that it can issue a warning that the concentrate container should be replaced. When the concentrate container is empty, the valve 211 can be closed and the gear pump 212 can be controlled to stop the pumping of concentrate. At the same time, a signal can be sent to a control unit via the wireless interface 204 so that it issues an error message and, if necessary, terminates affected processes to avoid damage.

The outlet 207 for fresh cooling lubricant emulsion can be designed in such a way that if there is no connection to a line 218, the outlet 207 is blocked, so that no cooling lubricant emulsion can escape into the environment. In this case, the flow meters 210 and 213 do not detect any flow, even if the valve 211 is open and/or the gear pump 212 is running. In this case, a signal can be sent to a control unit so that it issues an error message.

FIG. 2 shows a schematic representation of a further embodiment of a provision unit 200. This differs from the embodiment according to FIG. 1 in that the supply unit 200 is set up to deliver fresh water from a fresh water container instead of being connected to a pressurized fresh water line. In this embodiment, the internal line that leads from the fresh water connection 205 to the static mixer 208 is designed in the same way as the internal line that leads from the concentrate connection 206 to the mixer, and thus includes a volumetric pump, for example in the form a gear pump 212, a flow meter, for example in the form of an oval gear flow meter 213, and a check valve 214 to avoid contamination of the water in the fresh water tank.

Furthermore, the provision unit 200 in this embodiment includes one or more additive connections 221, which can be connected to an additive container via an additive line 222. An internal line leads from the additive connection 221 to the static mixer 208, and is designed in the same way as the internal lines that lead from the concentrate connection and from the fresh water connection to the mixer 208. It thus includes a volumetric pump, for example in the form of a gear pump 212, a flow meter, for example in the form of an oval gear flow meter 213, and a check valve 214 in order to avoid contamination of the additive in the additive container.

In addition, the supply unit 200 in this embodiment comprises fill level sensors 215 for the concentrate container, the fresh water container and one or more additive containers, which can be designed in the same way as the fill level sensor 215 in FIG. 1 and which are set up to measure the fill levels in the concentrate container, the fresh water container and the additive container. Furthermore, the supply unit comprises a compressed air connection 223, which can be connected to a compressed air line 224. An internal line leads from the compressed air connection 223 to the static mixer 208 and comprises an adjustable valve 211 with which the flow of compressed air can be regulated. The internal line can additionally be connected to the level sensors 215 in order to provide the required compressed air. In this case, a pump 220, as shown in FIG. 1, is not required. As an alternative to the compressed air connection, the supply unit 200 can comprise a pump for generating compressed air, which is connected to the mixer 208 via an internal line. In this case, a check valve is provided instead of the adjustable valve 211 so that the pump for generating compressed air is not damaged by cooling lubricant emulsion.

To provide the fresh cooling lubricant emulsion with this embodiment of the provision unit 200, the concentrate connection 206 and a level sensor 215 are connected to a concentrate container via the concentrate line 217, the fresh water connection 205 and a level sensor 215 are connected to a fresh water container via the fresh water line 216, and the one or more additive connections 221 and a level sensor 215 are each connected to an additive container.

The gear pumps 212 are controlled to pump a defined amount of fresh water, concentrate or additives from the corresponding containers. The quantities actually conveyed are measured via the flow meter 213, and if there are deviations, the gear pumps 212 are activated accordingly in order to adjust the quantities conveyed to the defined quantity. The separate conveyance of additives is advantageous if individual additives from the cooling-lubricant emulsion in a machine tool are consumed disproportionately, which cannot be compensated for by conveying concentrate alone.

The delivery of fresh water and additives from corresponding containers can be particularly useful in embodiments of the system according to the invention in which the supply unit is regularly moved between different machine tools and fresh water connections are not available everywhere.

The compressed air connection 223 can be connected to a compressed air line 224. This serves in particular to remove the cooling lubricant emulsion from the internal line, the mixer 208 and the line 218 for coolant lubricant emulsion in the event that a coolant lubricant emulsion with a different concentration is to be provided, for example when changing the machine tool for which the coolant lubricant emulsion is provided.

FIG. 3 shows a schematic representation of an embodiment of a measuring unit 300 comprising sensors 311, 312 and 313 for determining at least one parameter of a cooling lubricant emulsion. The measuring unit 300 comprises a housing 301, an AC connection 302 which is designed to supply the measuring unit 300 with power, an AC-DC converter 303 in order to be able to supply the components of the measuring unit operated with DC current with DC current, and an interface 304 which is designed as a wireless interface for data transmission between the measuring unit 300 and a control unit. The measuring unit 300 also comprises an interface 305 which is designed for connection to a data cable via which communication with a distribution unit is enabled.

At the same time, the interface 305 is set up to function as a direct current source for a distribution unit connected via a data cable, with the power supply also being provided via the data cable. The interface 304 is connected to the electrically operated components of the measurement unit via an electronic circuit (not shown) to enable their control. Furthermore, the measuring unit 300 includes a connection 306 as an inlet for cooling lubricant emulsion, which can be connected to a line 308 for cooling lubricant emulsion, and a connection 307 as an outlet for cooling lubricant emulsion, which is connected to a line 309 for cooling lubricant emulsion can be.

The connections 306 and 307 are connected to each other via an internal line. The internal line is connected to the sensors 311, 312 and 313 for determining at least one parameter of a cooling lubricant emulsion, and is set up to conduct cooling lubricant emulsion past the sensors 311, 312 and 313 so that they determine at least one parameter of the cooling lubricant emulsion can determine. For example, the sensors can be a refractometer, a pH sensor and a conductivity sensor. In addition, the measuring unit can also contain other sensors, such as photometers and light barriers. Alternatively, the measuring unit can also comprise just a single sensor, for example just a refractometer, or two sensors.

In this embodiment, the at least one sensor 311, 312, 313 is followed by a check valve 310, which allows the flow of the coolant-lubricant emulsion only in the direction of the outlet connection 307. This prevents measurements from being falsified due to coolant-lubricant emulsion flowing back and reduces the risk of damage to the sensors 311, 312, 313.

When the measuring unit 300 is in operation, the inlet connection 306 is connected to a distribution unit via a line 308 and is supplied via this with cooling lubricant emulsion to be measured. The outlet connection 307 can also be connected to the same distribution unit via a line 309 in order to return the cooling lubricant emulsion to it. Alternatively, the line 309 can lead to a disposal vessel or directly to a tank from which the cooling lubricant emulsion to be measured originates.

Furthermore, during operation, the interface 305 is connected to the

distribution unit to supply it with power and a

To enable communication of the distribution unit with a control unit via the wireless interface 304. During operation the cooling

Lubricant emulsion is passed past the at least one sensor 311, 312, 313 and at least one parameter of the cooling lubricant emulsion is determined by the sensors 311, 312, 313. The measurement data are sent via the interface 304 to a control unit, where they are further processed.

FIG. 4 shows a schematic representation of an embodiment of a distribution unit 400, which is designed to be connected to a measuring unit, a supply unit and a tank and to regulate the exchange of cooling lubricant emulsion between them.

The distribution unit 400 comprises a housing 401 and an interface 402 which is designed to be connected to a measuring unit via a data cable and to communicate with a control unit via the data cable and an interface of the measuring unit. At the same time, the interface 402 is designed to to supply power to the distribution unit via the data cable and via the power connection of the measuring unit. The interface 402 is connected to the electrically operated components of the distribution unit via an electronic circuit (not shown) to enable their control.

Furthermore, the distribution unit 400 includes a connection 403 as an inlet for fresh cooling lubricant emulsion, which can be connected to a line 218 for fresh cooling lubricant emulsion. The line 218 for fresh coolant lubricant emulsion can be the line 218 as shown in FIG. 1 and 2 shown correspond. Furthermore, the distribution unit 400 shown here includes a bidirectional connection 404, which can be connected to a tank via a line 411 and can function both as an inlet for cooling lubricant emulsion from the tank and as an outlet for fresh cooling lubricant emulsion into the tank. In addition, the distribution unit 400 includes a connection 405 as a further outlet for cooling-lubricant emulsion, which can be connected to a measuring unit via a line 308. Line 308 may correspond to line 308 as shown in FIG. 3 shown correspond.

Furthermore, the distribution unit 400 includes, as an inlet for coolant-lubricant emulsion that has been subjected to a measurement, a connection 406, which can be connected to a measuring unit via a line 309, and as an outlet for this coolant-lubricant emulsion, a connection 407, which has a Line 412 can be connected to a tank. Line 309 may correspond to line 309 as shown in FIG. 3 shown correspond.

An internal line leads from the inlet port 403 for fresh cooling lubricant emulsion to the bidirectional port 404 with a branch to the outlet port 405. Between the inlet port 403 and the branch, the line includes a flow meter, which in this embodiment is called a turbine 414 is designed, as well as a valve 409, for example a solenoid valve, which is closed in the normal state and can be opened if necessary to enable the flow of fresh cooling lubricant emulsion. In the branch that leads to the outlet connection 405, the internal line contains a further valve 408, for example a solenoid valve, which is open in the normal state and can be closed if necessary. In addition, the internal line may include a further valve 410 between the branch and the bidirectional outlet 404, which is open in the normal state. From the inlet connection 406 for cooling lubricant emulsion that has been subjected to a measurement, another internal line leads to the outlet connection 407, through which the cooling lubricant emulsion that has been subjected to a measurement can be passed into a tank. This internal line is connected to a pressure sensor 413.

Furthermore, the distribution unit 400 includes the fill level sensor 500, which z. B. is designed as an ultrasonic sensor and can measure the level in a tank. Accordingly, the distribution unit 400 is set up to be attached to such a tank in order to be able to determine the fill level therein.

During operation, the inlet connection 403 for fresh cooling lubricant emulsion is connected to a supply unit via a line 218, the bidirectional connection 404 is connected to a tank for cooling lubricant emulsion via a line 411, and the outlet connection 405 is connected to the cooling lubricant emulsion via a line 308 Inlet port of a measuring unit connected, the inlet port 406 connected via a line 309 to an outlet port of the measuring unit, and the outlet port 407 connected via a line 412 to the tank for cooling lubricant emulsion. Furthermore, the distribution unit is attached to the tank in order to be able to measure the level in it. Since in this embodiment there is no feed pump for the cooling-lubricant emulsion from the tank, the line 411 is additionally connected to a feed pump that feeds the cooling-lubricant emulsion from the tank into the

Distribution unit 400 promotes. Alternatively, a feed pump can be installed in the

distribution unit 400, or be installed in a measuring unit connected to it, which then draws the cooling-lubricating emulsion through the distribution unit via the line 411 and the line 308.

In the normal state, the distribution unit 400 is set up to direct cooling lubricant emulsion from the tank into the measuring unit for the measurement, since the other states (calibration and conditioning) only occur when necessary. Therefore, the valve 409, which regulates the flow of fresh cooling lubricant emulsion, is closed in the normal state, and the valves 408 and 410, which regulate the flow from the tank into the distribution unit and from the distribution unit into the measuring unit, are open. This ensures that only the cooling lubricant emulsion comes out of the Tank is subjected to a measurement without the measurement being falsified by fresh coolant lubricant emulsion.

In the sensor calibration state, the valve 410, which regulates the flow from the tank into the distribution unit 400, is closed and the valve 409, which regulates the flow of fresh coolant-lubricant emulsion, is opened. If the valve 410 is not present, the flow from the tank into the distribution unit 400 is prevented by appropriately controlling a corresponding feed pump.

In the conditioning state, the valve 408, which regulates the flow from the distribution unit 400 into the measuring unit, is closed, and the valve 409, which regulates the flow of fresh cooling lubricant emulsion, is opened.

The cooling lubricant emulsion which is returned from the measuring unit to the distribution unit 400 is, in this embodiment, led into the tank through the outlet 407 and a line 412 connected thereto.

The pressure sensor 413 is designed to monitor the pressure in the internal line between the connections 406 and 407. In the event of a sharp increase in pressure (e.g. if the line 412 is clogged, or the connection 407 is blocked because no line is connected) or a drop in pressure (e.g. if a line is severed, or the line 309 is not connected to the connection 406 or is clogged), a signal can be sent to the control unit via the interface 402 so that it issues a corresponding warning.

The level sensor 500 continuously measures the level in the tank and sends the measurement data via the interface 402 and an interface of the measuring unit to a control unit, where the data is further processed.

FIG. 5 shows a schematic representation of a further embodiment of a distribution unit 400, which is set up to be connected to a measuring unit, a supply unit and a tank and to regulate the exchange of cooling-lubricant emulsion between them.

This embodiment differs from that in FIG. 4 illustrated embodiment in that instead of a bidirectional connection 404 a unidirectional inlet connection 416 is provided, which can be connected to a tank via a line 419, and a unidirectional outlet 417 for fresh cooling lubricant emulsion is provided, which can be connected to the tank via a further line 420. Furthermore, the distribution unit 400 in this embodiment includes a further outlet 418 for cooling lubricant emulsion that has been subjected to a measurement, which can be connected to a line 421 through which cooling lubricant emulsion is discarded or disposed of.

In this embodiment, an internal line leads from the fresh cooling lubricant emulsion inlet 403 to the fresh cooling lubricant emulsion outlet 417, with a branch leading to the outlet port 405. The internal line includes a check valve 424 to prevent the flow of the fresh cooling lubricant emulsion in the wrong direction and a flow meter in the form of a turbine 414 to determine the amount of fresh cooling lubricant emulsion flowing through, both of which are located between the fresh cooling lubricant emulsion inlet 403 and the branch. Furthermore, the internal line includes a three-way valve which regulates the flow direction of the fresh cooling lubricant emulsion towards the outlet port 417 or the outlet port 405. In the normal state, the three-way valve is open towards the outlet port 417 and closed towards the outlet port 405.

Between the inlet connection 416 for cooling lubricant emulsion from the tank and the outlet connection 405, the distribution unit 400 in this embodiment also includes an internal line, which can partially coincide with the branch of the internal line starting from the inlet 403. This internal line includes a volumetric pump 422, which is designed as a gear pump and is set up to convey cooling lubricant emulsion from the tank through the distribution unit into the measuring unit, as well as a flow meter 423 in the form of an oval gear flow meter (optional), which is set up to check the amount of cooling lubricant emulsion delivered.

The internal line between the inlet port 406 for cooling lubricant emulsion which has been subjected to measurement and the outlet 407 for this, which can be connected to the tank via a line 412, additionally comprises a branch that leads to the outlet 418, via which the cooling lubricant emulsion can be disposed of. This internal line comprises a check valve 424 between the connection 406 and the branch, which prevents the cooling lubricant emulsion already examined from flowing into the measuring unit. This check valve can replace the check valve shown in FIG. 3 in the measuring unit if one is required. This internal line also comprises a valve 425, e.g. a solenoid valve, which is normally open and is located between the branch and the outlet 407, and a valve 426, e.g. a solenoid valve, which is normally closed and is located between the branch and the outlet 418.

In this embodiment, the outlets 407 and 417 that direct coolant-lubricant emulsion into the tank may be the same outlet, eliminating the need for a connector and a line.

The operation of this embodiment is different from the operation of the one shown in FIG. 4 illustrated embodiment in that instead of the bidirectional connection 404, the unidirectional connections 416 and 417 are connected to the tank via lines 419 and 420, respectively, and the outlet connection 418 is connected to a line 421, via which the cooling lubricant emulsion can be disposed of .

In the normal state, the distributor unit 400 is set up to direct cooling lubricant emulsion from the tank into the measuring unit for measurement, since the other states (calibration, disposal) only occur when necessary. Therefore, the valve 426, which regulates disposal, is closed in the normal state, and the valve 425, which regulates the flow from the measuring unit into the tank, is open. Furthermore, the three-way valve 415 is closed in the normal state in the direction of the connection 405, which leads to the measuring unit, and open in the direction of the outlet 417, which leads to the tank. This ensures that only the cooling lubricant emulsion from the tank is subjected to a measurement, without the measurement being distorted by fresh cooling lubricant emulsion. At the same time, it is possible for the cooling lubricant emulsion from the tank to be subjected to a measurement in the measuring unit, while the cooling lubricant emulsion in the tank is conditioned by following up with fresh cooling lubricant emulsion. In the In the normal state, the cooling lubricant emulsion is continuously pumped by the volumetric pump 422 from the tank into the distribution unit 400 and from the distribution unit 400 into the measuring unit, with the flow being controlled by the flow meter 423. If no flow is detected, a signal can be sent to the control unit, for example, so that a warning is issued.

For conditioning, the distribution unit 400 remains in the normal state and the flow of the fresh cooling lubricant emulsion can be controlled solely by the supply unit.

In the state of sensor calibration, the three-way valve 415 is opened towards the outlet 405 and closed towards the outlet 417, and the feed pump 422 is stopped so that the calibration is not distorted by coolant lubricant emulsion from the tank.

A closure of the three-way valve 415 is provided in the event that the supply unit is separated from the distribution unit 400 or several distribution units 400 are connected to the supply unit.

FIG. 6 shows a schematic representation of an embodiment of the system 100 according to the invention (delimited by a dashed frame), comprising a supply unit 200, a measuring unit 300, a distribution unit 400, a level sensor 500 and a control unit 600, wherein these components of the system 100 are connected for operation.

The provision unit 200, the measuring unit 300 and the distribution unit 500 in FIG. 6 correspond to the embodiments shown in FIGS. 1, 3 and 4, whereby these are shown in a significantly simplified manner. The connections therefore correspond to the connections shown in FIGS. 1, 3 and 4, but are not provided with reference symbols for the sake of clarity.

The supply unit 200 is connected to an AC power source (not shown) via a power cable 80 and to a fresh water source (not shown) via a fresh water line 216. Furthermore, the supply unit is connected to a concentrate container 70 via a concentrate line 217. The supply unit 200 is connected to a concentrate container 70 via a line 218 for fresh cooling lubricant emulsion is connected to the distribution unit 400. Furthermore, a wireless data connection is established between the supply unit 200 and the control unit 600, via which the supply unit 200 and the components contained therein are controlled.

The distribution unit 400 is attached to a tank 60 above the surface of the cooling lubricant emulsion and contains the level sensor 500, which is used to measure the level in the tank. The distribution unit is also connected to a tank 60 via a suction line 411, the end of the suction line 411 that is connected to the tank being immersed in the cooling lubricant emulsion and surrounded by a filter basket 40. The end of the suction line 411 is also equipped with a liquid pump 50, with which the cooling lubricant emulsion is conveyed into the distribution unit 400 after being filtered by the filter basket 40. The distribution unit 400 is also connected to the tank 60 via a return line 412, through which the cooling lubricant emulsion that has been subjected to a measurement is fed into the tank. The end of the return line 412 is also surrounded by a filter basket 40 to prevent particles from accidentally entering the distribution unit 400 or the measuring unit 300.

The distribution unit 400 is also connected to the measuring unit 300 via a line 308, via which the cooling-lubricant emulsion is passed into the measuring unit, and via a further line 309 connected to the measuring unit 300, via which the cooling-lubricant emulsion is fed into the distribution unit after the measurement 400 and the tank 60 is guided. In addition, the distribution unit 400 is connected to the measuring unit 300 via a data cable 90, which simultaneously functions as a power cable, which ensures a power supply to the distribution unit 400 via the power connection of the measuring unit 300 and data exchange between the distribution unit 400 and the control unit 600 via the wireless Interface of the measuring unit is made possible.

The measuring unit 300 is connected to a power source (not shown) via a power cable 80. The power from the power source is used to supply both the measuring unit 300 and the distribution unit 400 (via the data cable 90). Furthermore, a wireless data connection is established between the measuring unit 300 and the control unit 600, via which the measuring unit 300 and the components contained therein, as well as the Distribution unit 400 (via data cable 90) and the components contained therein are controlled and measurement data are transmitted.

The control unit 600 is, for example, a computer that can communicate with the provision unit 200, the measuring unit 300 and the distribution unit 400 (via the interface of the measuring unit 300 and the data cable 90) via a wireless interface and can control them or receive information from them. Alternatively, the distribution unit 400 can have its own power connection and communicate with the control unit 600 via its own (e.g. wireless) interface.

FIG. 7 shows a schematic representation of an embodiment of the system 100 according to the invention (delimited by a dashed frame), comprising a supply unit 200, a measuring unit 300, a distribution unit 400, a level sensor 500 and a control unit 600, whereby these components of the system 100 are connected for operation. In the present case, only the housings of the supply unit 200, the measuring unit 300 and the distribution unit 400 are shown. The connections essentially correspond to those shown in FIG. 6, whereby these are not provided with reference symbols for clarity. The connections are partly located in other places.

The provision unit 200 and the distribution unit 300 are mounted on a machine tool 10. The distribution unit 400 is as in the embodiment according to FIG. 6 attached to a tank 60, and includes the level sensor 500 to measure the level in the tank 60. The tank 60 is connected to the machine tool 10 to supply it with cooling lubricant emulsion.

The provision unit 200 and the measuring unit 300 can be supplied with power from the machine tool or can be connected to separate power sources via power cables.

In this embodiment, the system according to the invention is set up to condition the cooling-lubricant emulsion for a single machine tool 10. FIG. 8 shows a schematic representation of a further embodiment of the system 100 according to the invention (delimited by a dashed frame). This embodiment differs from that in FIG. 7 illustrated embodiment in that the system 100 additionally comprises further measuring units 300', further distribution units 400' and further fill level sensors 500', all of which are supplied with fresh coolant-lubricant emulsion by the same supply unit 200. The system is also additionally set up to condition the cooling-lubricant emulsions in further tanks 60' for further machine tools 10'.

Furthermore, the provision unit 200 is not mounted on a machine tool and is connected to a separate power source.

The control unit controls the supply unit 200, as well as all measuring units 300, 300', all distribution units 400, 400' and all level sensors 500, 500'.

FIG. 9 shows a schematic representation of another embodiment of the system 100 according to the invention. This embodiment differs from the embodiment shown in FIG. 8 in that the system 100 comprises a line 700, which is a form of the line 218 for fresh coolant-lubricant emulsion. The line 700 is designed as a flexible hose and comprises a free end 701, which comprises an identification feature 702 in the form of an RF ID transponder that is uniquely assigned to the line 700 and the supply unit 200.

The free end 701 and the connection 403 or 403' for fresh coolant-lubricant emulsion of the distribution unit 400 or 400' can be connected to one another via a quick-release fastener. The connections 403 and 403' are also designed to recognize the identification feature 702 by connecting it to an RFID reader. The distribution unit 400 or 400' can read the identification feature 702 when a connection is established with the free end 701 and transmit the data to the control unit 600.

The control unit 600 determines which of the distribution units 400 or 400 'has recognized the identification feature 702 and has been connected to the provision unit 200 to which the identification feature 702 belongs, and controls it Provision unit 200, the corresponding distribution unit 400 or 400', the corresponding fill level sensor 500 or 500' and the corresponding measuring unit 300 or 300' as a coherent system for conditioning the lubricant emulsion in the tank 60 or 60' for the machine tool 10 or 10'.

The other distribution unit, the other measuring unit and the other level sensor continuously carry out measurements of the at least one parameter of the cooling lubricant emulsion and the level in the other tank of the machine tool, and send a signal to the control unit 600 when conditioning of the cooling lubricant emulsion in this Tank or calibration of at least one sensor of this measuring unit is required. The control unit 600 then issues a corresponding warning.

Furthermore, in this embodiment, the supply unit 200 is mounted on a concentrate container 70 which is placed on a mobile trolley 71, whereby the supply unit becomes movable.

FIG. 10 shows a schematic representation of an embodiment of a combination of distribution unit 400 and measuring unit 300 of the system 100 according to the invention. This embodiment differs from the embodiment shown in FIG. 4 in that the distribution unit 400 and the measuring unit 300 have a common housing 301/401, and thus the components of the measuring unit 300 (delimited by a dashed frame), as shown in FIG. 3, and the components of the distribution unit 400, as shown in FIG. 4, are contained in this housing.

In this embodiment according to FIG. 10 are the interface 305, which is in the measuring unit 300 according to FIG. 3 is included, and the interface 402, which is in the distribution unit 400 according to FIG. 4 is included, is unnecessary, since the power supply of both units can take place via the common AC connection 302 and the AC-DC converter 303, and the data transmission between both units and a control unit, as well as the control of the electrically operated components of both units via the common interface 304 can be done without using an additional data or power cable between the two units. The connections 306, 307, 405, 406 are also for the Liquid exchange between the measuring unit 300 and the distribution unit 400 is unnecessary since the liquid exchange takes place via internal lines.

The use of a combination of distribution unit 400 and measuring unit 300 in a housing 301/401 enables easier handling for the end user of the system according to the invention. A corresponding combination can also be made from any other embodiments of the measuring unit 300 and the distribution unit 400 in a housing.

FIG. 11 shows an embodiment of the system 100 according to the invention, as shown in FIG. 6, but using the parameters shown in FIG. 10 shown combination of distribution unit 400 and measuring unit 300, instead of the separate units. The lines 308 and 309 as well as the data cable 90 are not required due to the use of this combination, which enables easier handling for the end user of the system according to the invention. The combination of measuring unit 300 and distribution unit (400) in a common housing (301, 401) can be used in any embodiment of the system according to the invention instead of the separate units.

The invention is illustrated in more detail by the following examples and claims.

Examples

In the following examples, a cooling lubricant emulsion KSS1 is used, which is obtained by diluting a concentrate available under the name Blasocut 4000 Strong from Blaser Swisslube. Blasocut 4000 Strong is a water-miscible cooling lubricant based on mineral oil.

example 1

As the system 100 according to the invention, a structure as shown in FIG. 7 is used, wherein the supply unit 200 is one as shown in FIG. 1, the measuring unit 300 is one as shown in FIG. 3 and the distribution unit 400 is one as shown in FIG. 4. The power connections are all connected to a power source, the supply unit 200 is also connected to a Concentrate container and connected to a pressurized fresh water line.

In this example, the tank 60 has a capacity of 1000 kg (= 100%)

A combination of a laptop and a WLAN router is used as the control unit 600, whereby drivers for the provision unit 200, the measuring unit 300 and the distribution unit 400 (including the level sensor 500) are installed on the laptop, and the wireless interfaces are WLAN interfaces. All WLAN interfaces are connected to the WLAN router. A digital user interface is also installed on the laptop, which prompts the user to enter a target concentration for the tank, a target fill level for the tank, a tolerance range for the target concentration and a tolerance range for the target fill level, and provides the option of selecting the corresponding values from a database. An emergency stop button (PIN protected) and a start button are also shown.

The following settings are selected, assuming the concentration of 100% for the pure concentrate (data in wt.%; tolerances in absolute values), and the process is started. SK60 is the target concentration in tank 60, TK60 is the tolerance range around SK60, SF60 is the target level in tank 60, TF60 is the tolerance range around SF60, IK60 is the measured or calculated actual concentration in tank 60, IF60 is the measured actual fill level in tank 60; AF60 is the difference SF60-IF60; EK60 is the concentration of the fresh cooling lubricant emulsion that is required to achieve the target concentration SK60 when re-applying with the amount AF60.

The control unit 600 is programmed to control the system 100 such that a cascade of the following steps is carried out, wherein the reference numerals correspond to those in FIGS. 1, 3, 4, 7 and 8. Other cascades of steps are also conceivable. In particular, the flow rates can be varied in order to control the speed and accuracy of the tracking. Initial calibration of sensors 311 (refractometer), 312 (pH sensor), 313 (conductivity sensor):

1 ) Close valve 410 to the tank; Open valve 408 to measuring unit 300; Open valve 409;

2) Open valve 211 until fresh water flows at a rate of 9 kg/min (controlled by turbine 210; if no flow is detected, stop the process and issue an error message); Start pump 212 so that concentrate flows at a rate of 1 kg/min (checked by flow meter 213; if no flow is detected, stop process and issue error message); Continue pumping water and concentrate for 15 seconds (rinsing the sensors with fresh cooling lubricant emulsion with a concentration of SK60 = 10%); storing the measured values transmitted from the sensors 311, 312 and 313 to the control unit for 5 seconds; assigning a concentration of SK60 = 10% to the received measured values using the control unit 600;

3) repeat the steps listed under 2) at least for the following flow rate ratios of water to concentrate: 9.2 kg/min water and 0.8 kg/min concentrate, with assignment of the measured parameters to a concentration of SK60-TK60 = 8% ; 8.8 kg/min water and 1.2 kg/min concentrate with assignment of the measured parameters to a concentration of SK60+TK60 = 12%;

4) calculate a calibration curve, which can be used to assign measured parameters of the cooling lubricant emulsion to a concentration.

Initial filling of tank 60:

5) Calculating the concentration of the cooling lubricant emulsion (IK60) in the tank 60 based on the amount of concentrate and water that has already flowed through (here IK60 = 10%, since the mean value is 8%, 10% and 12%); Measuring the fill level with the fill level sensor 500 and transmitting the value to the control unit 600 (in this case IF60 = 1%, since a total of 1 minute was conveyed at 10 kg/min); Calculate the difference AF60 from SF60 and IF60 (AF60 = SF60-IF60 = 89%); Calculating the required concentration EK60 of the fresh cooling lubricant emulsion that is required to reach the target concentration when reaching SF60 with the calculated level difference (EK60 = (SF60 x SK60 - IF60 x IK60)/ AF60 = 10%) 6) Open valve 410 to tank 60; Close valve 408 to measuring unit 300; Open valve 211 until fresh water flows at a rate of 90 kg/min (controlled by turbine 210); Start pump 212 so that concentrate flows at a rate of 10 kg/min (controlled by flow meter 213); Convey until the fill level sensor 500 reports that the target fill level of SF60 = 90% has been reached (in this case after approx. 8.9 minutes);

7) Close valve 409; close valve 211; stop pump 212.

Measurement of at least one parameter and conditioning:

8) Open valve 408 to the measuring unit 300; start pump 50 (feeding of cooling lubricant emulsion from tank 60 into the measuring unit 300); continuously measure the at least one parameter with the sensors 311, 312 and 313 and transmit the measured values to the control unit; continuously measure the fill level in tank 60 with the fill level sensor 500 and transmit the measured value to the control unit 600; If IF60 falls below SF60-TF60 = 85%, or IK60 falls below SK60-TK60 = 8% or rises above SK60+TK60 = 12%, continue with step 9);

9) calculate the difference AF60 = SF60-IF60; Calculate the required concentration EK60 = (SF60 x SK60 - IF60 x IK60)/ AF60, which is required to achieve the target concentration SK60 when following up with the required amount of AF60 of fresh coolant lubricant emulsion.

10) Stop pump 50; close valve 408 to measuring unit 300; open valve 409; open valve 211 so that fresh water flows in a quantity of (100%- EK60) x 100 kg/min (control by turbine 210); start pump 212 so that concentrate flows in a quantity of EK60 x 100 kg/min (control by flow meter 213); pump the fresh cooling lubricant emulsion until the level sensor 500 reports that the target level of SF60 = 90% has been reached (time is approx. (AF60/100 kg) min);

11) Close valve 409; Close valve 211; stop pump 212; continue with step 8). Recalibration:

12) If SK60 is not reached when repeating step 8) after carrying out step 11): stop pump 50; Close valve 410 to the tank; Open valve 409; Repeat step 2) of the initial calibration; adjust the calibration curve based on the new measured values for SK60; continue with step 8).

The invention is not limited to the exemplary embodiments described here and the aspects highlighted therein. Rather, within the range specified by the claims, a large number of modifications are possible, which are within the scope of professional action.

Reference symbol list

10, 10' machine tool

40 filter basket

50 Pump

60, 60' tank

70 concentrate containers

80 power cables

90 data cables (with power supply)

100 Inventive system

200 delivery unit

201 , 301 , 401 Housing

202, 302 AC power connector

203, 303 AC-DC converter

204, 304 Wireless interface

205-207, 221, 223, 306, 307, 403-407, 403', 416-418 fluid connection

208 static mixer

209, 214, 310, 424 check valve

210, 414 turbines

211 , 408, 409, 410, 425, 426 Valve

212, 422 volumetric gear pump

213, 423 Oval gear flow meter

215 Level sensor for concentrate, fresh water or additive tank;

216-218, 222, 308, 309, 411, 412, 419-421 fluid line

219, 413 pressure sensor

220 compressed air pump

224 compressed air line

300, 300' measuring unit

305, 402 Interface for data cable

311-313 Sensor

400, 400' distribution unit

415 Three-way valve

500 level sensor

600 control unit

700 Cable with free end

701 Free ending

702 identification feature

Claims

Claims System (100) for conditioning a cooling lubricant emulsion for machine tools (10, 10') comprising: a measuring unit (300) comprising at least one sensor (311, 312, 313) for determining at least one parameter of the cooling lubricant emulsion, a supply unit ( 200) for providing fresh cooling lubricant emulsion, which is set up to mix a defined amount of a concentrate with a defined amount of water, and to provide the mixture as a fresh cooling lubricant emulsion, and a fill level sensor (500), which is set up to measure the fill level to measure in a tank (60, 60'), characterized in that the provision unit (200) is spatially separated from the measuring unit (300) and is not in direct fluid exchange with the measuring unit (300), wherein the system (100) further a distribution unit (400) which is set up to be connected to the measuring unit (300), the supply unit (200) and a tank (60, 60 '), and to regulate the exchange of coolant lubricant emulsion between them, wherein the System (100) also includes a control unit (600) which is set up to control the provision unit (200), the measuring unit (300), the distribution unit (400) and the fill level sensor (500) and to exchange data with them. System (100) according to claim 1, wherein the provision unit (200) has a housing (201) and the measuring unit (300) and the distribution unit (400) have a common housing (301, 401). System (100) according to claim 1 or 2, wherein the control unit (600) is set up to carry out at least the following steps: a) controlling the supply unit (200) so that it mixes a defined amount of a concentrate with a defined amount of water and the mixture as providing fresh cooling lubricant emulsion; b) Controlling the distribution unit (400) so that it can provide fresh cooling

Lubricant emulsion from the supply unit (200) into the measuring unit (300) or into the tank (60, 60'), or coolant-lubricant emulsion from the tank (60, 60') into the measuring unit (300), and/or optionally at least part of the coolant-

Lubricant emulsion leads from the measuring unit (300) into the tank (60, 60'); c) receiving measurement data from the at least one sensor (311, 312, 313) of the measuring unit (300) and the fill level sensor (500); d) Calculating the follow-up quantity that is required to transfer the fill level in the tank (60, 60') from a measured actual fill level to a defined target fill level; e) Calculating the follow-up concentration of a fresh coolant lubricant emulsion, which is required for a calculated follow-up quantity in order to convert the measured actual concentration in the tank (60, 60 ') into a defined target concentration; f) calibrating the at least one sensor (311, 312, 313) of the measuring unit (300).

4. System (100) according to one of claims 1 to 3, wherein the fill level sensor (500) is installed in the distribution unit (400), and the distribution unit is adapted to be attached to a tank (60, 60 ') in order to To be able to measure the level in the tank (60, 60 ').

5. System (100) according to one of claims 1 to 4, further comprising a line (700) for fresh cooling lubricant emulsion which enables a reversible connection between the supply unit (200) and the distribution unit (400), the line (700 ) has at least one free end (701), wherein the at least one free end (701) has an identification feature (702), preferably an RFID transponder, which is uniquely assigned to the line (700), and wherein the at least one free end (701) is set up to be reversibly connected to the provision unit (200), the distribution unit (400) or both, preferably via a quick-release fastener, and wherein the distribution unit (400), the provision unit (200) or both are set up to have the identification feature (702) during manufacture a connection with the at least one free end (701).

6. System (100) according to one of claims 1 to 5, wherein the system comprises at least one further measuring unit (300'), at least one further distribution unit (400') and at least one further level sensor (500'), wherein the further level sensor (500') is designed to measure the level in a tank (60, 60'), wherein the supply unit (200) is spatially separated from the further measuring unit (300') and is not in direct fluid exchange with the further measuring unit (300'), and the further distribution unit (400') is designed to be connected to the further measuring unit (300'), the supply unit (200) and a tank (60, 60') and to regulate the exchange of cooling lubricant emulsion between them, and the system (100) is designed to condition the cooling lubricant emulsions in at least two tanks (60, 60'), and wherein the control unit (600) is arranged to determine through which distribution unit (400, 400’) the fresh cooling-lubricating emulsion from the supply unit (200) is fed.

7. System (100) according to one of claims 1 to 6, wherein the provision unit (200) has a wireless interface (204), and the control unit (600) is configured to communicate with the provision unit (200) via the wireless interface (204), and preferably wherein the measuring unit (300) has a wireless interface (304), and the control unit (600) is configured to communicate with the measuring unit (300) via the wireless interface (304).

8. System (100) according to one of claims 1 to 7, wherein the distribution unit (400) is configured to be connected to the measuring unit (300) via a data cable interface (402), and the control unit (600) is configured to communicate with the distribution unit (400) via the measuring unit (300) and the data cable interface (402).

9. System (100) according to one of claims 1 to 8, characterized in that the at least one parameter is selected from the refractive index, the pH value, the light transmittance, the reflectance, the oil content and the conductivity of the cooling

Lubricant emulsion. System (100) according to one of claims 1 to 9, wherein the supply unit (200) is configured to be reversibly connected to the distribution unit (400) and, at least in the separated state, to be moved independently of the measuring unit (300), the distribution unit (400) and the tank (60, 60'). System (100) according to one of claims 1 to 10, wherein the supply unit (200) is connected to the distribution unit (400) via a line (218) and is in fluid exchange, the measuring unit (300) is connected to the distribution unit (400) via at least one line (308, 309) and is in fluid exchange, the distribution unit (400) is in fluid exchange with a tank (60, 60') via at least one line (411, 412, 419, 420), and the control unit (600) has a data connection with the supply unit (200), the measuring unit (300) and the distribution unit (400). Method for conditioning a cooling lubricant emulsion for machine tools (10), wherein a cooling lubricant emulsion is provided in a tank (60) and wherein the cooling lubricant emulsion is removed from the tank (60), at least one parameter of the cooling lubricant emulsion is detected using at least one sensor (311, 312, 313), the concentration of the cooling lubricant emulsion in the tank (60) is determined from the at least one parameter, and the cooling lubricant emulsion is at least partially returned to the tank (60), and the filling level in the tank (60) is measured using a fill level sensor (500), a required follow-up concentration and follow-up quantity is calculated and the fresh cooling lubricant emulsion is provided with the calculated follow-up concentration in the calculated follow-up quantity, further comprising the step:

Calibrating the at least one sensor (311, 312, 313) by rinsing the at least one sensor (311, 312, 313) and carrying out a measurement with fresh cooling lubricant emulsion which has a defined ratio of concentrate to water, characterized in that the fresh cooling lubricant emulsion is provided by a supply unit (200), the sensor (311, 312, 313) is part of a measuring unit (300), the supply unit (200) is spatially separated from the measuring unit (300) and there is no direct fluid exchange with the measuring unit (300), and the supply unit (200), the measuring unit (300) and the tank (60) are connected to a distribution unit (400) which regulates the exchange of coolant and lubricant emulsion between them, and wherein the method is controlled by a control unit (600). A method according to claim 12, wherein the method is carried out with the system (100) according to any one of claims 1 to 11. Method according to claim 12 or 13, wherein a cooling lubricant emulsion is provided in a respective tank (60, 60') for at least two machine tools (10, 10') and each of the tanks (60, 60') is each equipped with a distribution unit (400, 400'), each of which is connected to a measuring unit (300, 300'), the fresh cooling lubricant emulsion being provided in a common supply unit (200) and the exchange of the cooling lubricant emulsion being carried out between the supply unit ( 200) and the distribution units (400, 400') are controlled manually by changing the distribution unit (400, 400') connected to the provision unit (200) or automatically by the control unit (600). Method according to one of claims 12 to 14, comprising the following steps: aa) providing a fresh cooling lubricant emulsion, which has a defined ratio of concentrate to water, in the supply unit (200); bb) introducing the fresh cooling lubricant emulsion from the supply unit (200) into the measuring unit (300) with the distribution unit (400); cc) calibrating the at least one sensor (311, 312, 313) with the fresh cooling-lubricant emulsion fed into the measuring unit (300). Carrying out a measurement with the fresh cooling lubricant emulsion, which has a defined ratio of concentrate to water, optionally the fresh cooling lubricant emulsion being at least partially fed into the tank (60) after the measurement; dd) removal of cooling lubricant emulsion from a tank (60) and introduction of the cooling lubricant emulsion into the measuring unit (300); ee) measuring the at least one parameter of the cooling lubricant emulsion with the at least one sensor (311, 312, 313) in order to determine the actual concentration of the cooling lubricant emulsion in the tank (60) based on the at least one parameter, optionally the Cooling lubricant emulsion is at least partially returned to the tank (60); ff) measuring the level in the tank (60) with the level sensor (500); gg) Calculating the amount of replenishment required to reach a predetermined level in the tank (60); hh) calculating the follow-up concentration that is required at the calculated follow-up amount in order to condition the concentration of the coolant-lubricant emulsion in the tank (60) to a specified target value; ii) providing a fresh cooling lubricant emulsion, which has the calculated required replenishment concentration, in the calculated replenishment amount, in the provision unit (200); jj) introducing the fresh cooling lubricant emulsion into the tank (60), with the distribution unit (400) to condition the cooling lubricant emulsion in the tank (60). Method according to one of claims 12 to 15, wherein a target concentration of the cooling lubricant emulsion in a tank (60), a tolerance range for the concentration around the target concentration, a target fill level in the tank (60) and a tolerance range for the fill level can be set around the target fill level, with the control unit (600) carrying out at least the following steps: i) sending a request to the supply unit (200) to provide fresh cooling lubricant emulsion with a concentrate ratio defined for calibration to start on the water, and sending a request to the distribution unit (400) to initiate the delivery from the provision unit (200). provided cooling lubricant emulsion to the measuring unit (300), wherein the cooling lubricant emulsion from the measuring unit is optionally at least partially directed into the tank (60); ii) sending a request to the measuring unit (300) to carry out a measurement of at least one parameter with the at least one sensor (311, 312, 313) and to transmit the measurement data to the control unit (600) in order to use the at least one sensor (311, 312, 313) to calibrate; iii) sending a request to the supply unit (200) to end the provision of fresh cooling lubricant emulsion and sending a request to the distribution unit (400) to introduce the cooling lubricant emulsion provided by the supply unit (200) into the measuring unit (300 ) to end; iv) sending a request to the distribution unit (400) to begin removing cooling lubricant emulsion from the tank (60) and introducing it into the measuring unit (300), wherein the cooling lubricant emulsion from the measuring unit (300) at least is partially returned to the tank (60); v) sending a request to the measuring unit (300) to carry out a measurement of at least one parameter with the at least one sensor (311, 312, 313) and to transmit the measurement data to the control unit (600) in order to determine the actual concentration of the cooling Determine lubricant emulsion; vi) sending a request to the distribution unit (400) to stop removing the cooling-lubricant emulsion from the tank (60) and introducing it into the measuring unit (300); vii) sending a request to the level sensor (500) to measure the level in the tank (60) and transmit the measurement data to the control unit (600) in order to determine the actual level in the tank (60); viii) Check whether the determined actual fill level and the determined actual concentration are within the specified tolerance ranges; If yes: repeat steps v) to viii); if no: proceed to step ix); ix) Calculating the required replenishment quantity from the difference between the specified target level and the determined actual fill level, and calculating the replenishment concentration that is required in order to achieve this calculated follow-up quantity based on the actual concentration to reach the target concentration; x) sending a request to the provision unit (200) to start providing fresh cooling lubricant emulsion with the calculated follow-up concentration, and sending a

Requesting the distribution unit (400) to start introducing the cooling lubricant emulsion provided by the supply unit (200) into the tank (60) in order to condition the cooling lubricant emulsion in the tank (60); xi) When the target fill level is reached or the calculated

Replenishment quantity has been provided, sending a request to the provision unit (200) to stop the provision of fresh cooling lubricant emulsion, and sending a request to the distribution unit (400) to stop the introduction of the cooling lubricant emulsion provided by the provision unit (200) into the tank (60).