EP4210900A1

EP4210900A1 - System for automating a machine tool

Info

Publication number: EP4210900A1
Application number: EP21766112.3A
Authority: EP
Inventors: Klaus Hofmann
Original assignee: Zeroclamp GmbH
Current assignee: Zeroclamp GmbH
Priority date: 2020-09-07
Filing date: 2021-08-19
Publication date: 2023-07-19
Also published as: JP2023540460A; CN116113519A; US20240293904A1; WO2022048707A1; DE102020123316A1

Abstract

The invention relates to a system for automating a machine tool, comprising an external device (108) for feeding workpieces and/or tools to and/or discharging workpieces and/or tools from the machine tool (102), at least one actuator (110) for actuating a component of the machine tool (102) and/or at least one sensor (112) for detecting at least one signal of a display component (102a) or a state of the machine tool (102) or of the external device (108), and a control unit (106) which is configured to trigger at least one function of the machine tool (102) or the external device by actuating the at least one actuator (110) and/or to trigger at least one function of the external device (108) on the basis of a signal of the at least one sensor (112).

Description

System for automating a machine tool

The invention relates to a system for automating a machine tool.

A classic automation solution generally consists of a machine tool, a robot arranged outside the machine tool for feeding workpieces and/or tools to and/or removing workpieces and/or tools from the machine tool, a component store and a workpiece store. Grippers for the tools and clamping means for clamping workpieces are provided in a usually closed machining area of the machine tool, which can be opened for the supply and removal of workpieces or tools. Instead of an operator, the automation solution takes over the feeding of workpieces and/or tools to and/or the removal of workpieces and/or tools from the machine tool.

In such known systems for automating a machine tool, the machine tool and the other components are equipped with an electrical interface via which they communicate with one another or via which they communicate with a higher-level control unit, with the higher-level control unit being able to control the machine tool and the other components accordingly. The direct control of the clamping devices provided in the machine tool, which are generally operated with pressure oil or compressed air, is usually carried out by the machine tool itself to guide complex rotary feedthroughs for this clamping device through the rotary swivel table in order to route the pressure medium and, if necessary, electrical control lines for actuating directional control valves to the clamping device.

Typically, such communication interfaces from manufacturers of

Machine tools designed as proprietary interfaces to create your own to connect automation components. Third-party manufacturers of automation components are therefore usually denied access to the machine tool, either because the manufacturer does not disclose the electrical specifications of the interface or because complex mechanical adapters would be required to mechanically couple the components from the third-party manufacturer. In addition, in practice, many machine tools are not intended or suitable for integration into an automation solution and therefore do not have any suitable interfaces. The required hardware, in particular rotary feedthroughs for rotary swivel tables or automatic drives for opening and closing the machine doors, is not available either. A possible upgrade often fails due to the high costs involved.

The invention is therefore based on the object of creating a system for automating a machine tool, which integrates a machine tool that does not have suitable interfaces for connecting an automation solution, in particular an external device for feeding workpieces and/or tools to and/or the removal of workpieces and/or tools from the machine tool, and which can be implemented in a simple and cost-effective manner.

The aim is therefore to create automation that takes over all the activities of an operator for loading and unloading the machine without having to retrofit additional interfaces or automation hardware on the machine. Furthermore, the invention is based on the object of creating a computer program product as well as an actuator and a sensor for such a system.

The invention solves this problem with the features of patent claims 1 or 13, 14 and 15.

The invention is based on the finding that interfaces to an external device for feeding workpieces and/or tools to and/or removing workpieces and/or tools from the machine tool (hereinafter also referred to as "robot") machine tool to be automated can be dispensed with if appropriate Actuators and/or sensors are used which are connected to a control unit which is designed to trigger at least one function of the machine tool by activating the at least one actuator and/or at least one function of the external device depending on a signal from the at least one sensor trigger. This makes it possible for the system according to the invention, which represents an automation solution, to be able to take over certain tasks from an operator, for example pressing a start button on a control panel of the machine tool, opening and closing a door of the machine tool depending on a display on the control panel of the machine tool and the like . The external device can be designed as a stationary robot and can include one or more magazines for storing workpieces and/or tools. The external device is usually positioned (stationary) in front of the opening of the machining area of the machine tool, which can be closed by means of a door, and has at least one arm for feeding in and removing tools or tools.

Workpieces in and out of the machine tool. Of course, a plurality of workpieces and/or tools can also be fed in at the same time in one feeding process, or a plurality of workpieces and/or tools can be removed at the same time in a removal process. For this purpose, the plurality of workpieces and/or tools can also be arranged and held in a magazine.

The control unit can be integrated into the external device or designed as a higher-level control unit that communicates with a machine control unit included in the external device. The machine control unit and the higher-level control unit can be designed for wireless communication in order to be able to do without complex cabling.

In a very simple embodiment, the control unit can be integrated into the external device. In particular, the machine control unit and the control unit (which takes over the automation functions) can be integrated, ie designed as a single control unit. In this case, rudimentary automation can also consist in triggering at least one specific function of the external device depending on the signal from one or more sensors that detect a parameter or a state of the machine tool. Through the already existing coupling of the control unit to the machine control unit would not necessarily require an actuator for actuating a component of the machine tool in such a case, for example an electrical switch or another actuating element of the machine tool.

In another variant, only one or more actuators can also be provided, without a separate sensor being provided for detecting at least one signal of a display component or a state of the machine tool or the external device.

In most cases, however, one or more actuators and one or more sensors will be provided in order in particular to achieve as complete an automation of the machine tool as possible.

According to one embodiment of the invention, the at least one actuator and the at least one sensor are wirelessly connected to the control unit. As a result, the provision of communication cables between the sensors or actuators and the control unit can be dispensed with. This plays a role in particular with sensors or actuators that are arranged on a moving part of the machine tool, for example on a rotary swivel table.

In one embodiment of the invention, the at least one actuator can be designed as an operating element actuating device and have at least one electrically, pneumatically or hydraulically driven actuating element. The actuating element can, for example, be in the form of a linearly movable actuating element which is suitable for actuating a pressure switch or a pushbutton on a control panel of the machine tool.

In another variant, the actuator can be designed as a door opener for a single or double door of the machine tool. For this purpose, the actuator can also have an actuating device for opening and closing the door, which can also be designed as a double door, for example in the form of drive rollers. According to the invention, the actuator can also be designed as a clamping device for use in the machine tool. The clamping device can be used for the direct clamping of a workpiece or for fixing a further clamping device, for example a vice, which can also be designed as an actuator according to the invention.

According to one embodiment of the invention, the at least one sensor can be designed as an optical sensor, for example as a photodiode or camera. Such a sensor can be arranged, for example, on a control panel of the machine tool and can record the status of a light-emitting diode or the output on a screen (in the form of any displays or characters). The sensor can be designed in such a way that only the immediate sensor signal with the relevant information content is transmitted to the control unit or that signal processing already takes place in the sensor and only the result of the signal processing, for example an ON/OFF statement for a light-emitting diode, is sent to the Control unit is transmitted.

In one embodiment of the invention, the at least one sensor and/or the at least one actuator can be designed to be connectable, for example glued or screwed, to the machine tool, in particular an operating panel or a housing of the machine tool. This results in simple assembly for such a sensor or actuator. In particular, a suitable adhesive that is covered with a removable film can already be provided on one or more suitable fastening surfaces of a sensor or actuator. For installation, the foil only has to be removed and the sensor placed with the fastening surfaces on the relevant surface of the machine tool and pressed.

A sensor according to the invention can be designed to monitor the clamping force or a correct clamping state of a clamping device, in particular a clamping device according to the invention. In the latter case, the sensor and the actuator can also be designed as an integrated module. At this point it should be pointed out that each embodiment of a sensor or actuator can of course also be designed as an independent module.

According to one embodiment of the system according to the invention, selected or all sensors and actuators can be embodied autonomously and each have their own, in particular rechargeable, energy supply. The energy supply can in particular be an electrical energy supply, for example a rechargeable battery. The battery can be charged inductively, i. H. contactless or wired by connecting to a charging device. Of course, it is also possible to change the battery and charge it externally or to use non-rechargeable batteries. Furthermore or additionally, an energy supply in the form of a pneumatic pressure reservoir can also be provided. In this case, the recharging can take place by supplying compressed air, for example by means of a movable arm of the external device. The self-sufficient configuration of a sensor or actuator makes it possible to ensure the respective functionality without having to produce a permanently available energy supply via the machine tool or the external device.

As already explained above, according to the invention the external device can be designed as a stationary device with at least one movable arm for feeding workpieces and/or tools to and/or removing workpieces and/or tools from the machine tool. The at least one arm can also be used to supply compressed air to actuators that are designed to pneumatically actuate a respective actuating element.

According to the invention, the control unit can comprise a computer program which, when running in the control unit of the machine tool, is designed to communicate with the external device and to control the at least one actuator, possibly taking into account the information supplied by the at least one sensor, in such a way that the sequence of processes of the machine tool is automated, in particular starting a machining sequence for a workpiece, opening or closing a door of the machine tool, removing a partially or completely finished workpiece or feeding a workpiece to be machined and removing or feeding tools into the machine tool. The computer program can of course also be stored in the control unit or stored on a data medium or in a cloud and loaded from the data medium or the cloud into a main memory of the control unit.

Further embodiments of the invention result from the dependent claims.

The invention is explained in more detail below with reference to an embodiment shown in the drawing. Show in the drawing

1 shows a substantially perspective view of an embodiment of a system for automating a machine tool in connection with the machine tool;

Fig. 2 is a plan view of the illustration in Fig. 1;

FIG. 3 shows a plan view of the embodiment according to FIG. 1, but without the machine tool to be automated;

4 shows a perspective view of a self-sufficient actuator according to the invention; and

5 shows a representation analogous to FIG. 4, but with the actuator lifted off the fastening shoes.

1 shows an overall system 100 consisting of a machine tool 102 and a system 104 for automating a machine tool in an essentially perspective view. Only a control unit 106, which is included in the automation system 104, and the respective communication links are shown schematically in the form of a block diagram. FIG. 2 shows a top view of the overall system 100 according to FIG. 1. For the sake of better clarity, FIG. 3 again shows the automation system 104 without the machine tool 102 in the same views.

As can be seen from these figures, the automation system 104 includes, in addition to the control unit 106, an external device 108 for feeding workpieces and/or tools to and/or removing workpieces and/or tools from the machine tool, which are also included in this description referred to as a "robot" for short. Furthermore, the automation system 104 comprises a plurality of actuators 110 in the form of a clamping device 110a designed as a vice, in the form of a clamping device 110b designed as a zero-point clamping system (Fig. 2), in the form of a door opener device 110c and in the form of a control element actuating device 110d. Finally, the automation system 104 includes at least one sensor 112. In the present case, a sensor 112 is integrated into the operating element actuation device 110d (FIG. 4). At least one sensor (not shown) is also integrated in each of the actuators 110a, 110b and 110c. The vice 110a and the zero-point clamping system 110b can be pressure sensors if these components are designed as pneumatically or hydraulically operated components. The door opener device 110c can also include a sensor which, for example, detects the position of the door or the drive (and thus the door). The communication connections between these actuators 110 and the control unit 106 are therefore shown as bidirectional connections in FIGS.

With these components, the automation system 104 makes it possible to automate the machine tool 102 to a predetermined extent and, in the process, to carry out actions in an automated manner that have to be carried out by an operator in the case of a non-automated machine tool. This involves, in particular, feeding workpieces and/or tools to and/or removing workpieces and/or tools from machine tool 102, opening or closing a door 114 of the machine tool, which closes off the machining area, starting a machining cycle and the like. The robot 108 has at least one assignable arm 108a with which the robot 108 can grip workpieces or tools (not shown) and feed them into the machining area of the machine tool 102 or remove them from it. The robot can also have magazines (not shown) for storing or keeping workpieces and tools.

In the exemplary embodiment illustrated in the figures, a zero-point clamping system 110b is provided in the machining area of the machine tool 102, which system can be fastened, for example, to a rotary/pivoting table of the machine tool. In the example shown, an actuator 110 in the form of a controllable vice 110a is held on the zero-point clamping system 110b. The zero-point clamping system 110b is also designed as a controllable actuator 110. Both actuators 110a and 110b can be controlled at least to the effect that the respective actuator can be transferred to a clamped position or a released position by means of a control command.

It is of course also possible for sensors to be provided in each actuator, including each of the actuators 110a and 110b, which detect certain events or states, for example whether the respective actuator moves from one position to another and/or whether the specified position is actually reached or maintained. However, the relevant sensor(s) can also be designed as separate modules.

The actuator 110 embodied as a door opener device 110c has a drive which is embodied to move the door, which can be embodied as a sliding door, and to convert it from an open to a closed position. Like all other actuators, the door opener device 110c can be designed as an independent module. This module can also be subsequently connected to the frame of the machine tool 102 or to the floor in a position in which the drive is coupled to the movable door 114. Of course, the door opener device 110c can also have one or more sensors that detect the respective position of the drive and/or the door 114 . The actuator 110 embodied as an operating element actuating device 110d is arranged on an operating panel 102a of the machine tool 102 and is designed to actuate one or more associated operating elements of the operating panel 102a.

As can be seen from FIG. 4, the actuator 110d can also be designed as an independent module. An electrical, programmatic or hydraulic drive for an actuating element 118 is provided in a housing 116 of the operating element actuating device 110d. In the exemplary embodiment shown, the actuating element 118 is designed as a linearly movable, cylinder-like element which protrudes downwards from the housing 116 . The housing 116 has four feet 120 on its underside, with which the operating element actuating device 110d can be placed on the operating panel 102a and connected to it. The connection can take place, for example, by gluing or screwing. In any case, the connection must be designed in such a way that the housing is secured against displacement and lifting relative to or from the surface of the control panel 102a, even if the actuating element 118 is used to actuate the relevant control element (not shown) of the Control panels 102a is exercised. For assembly, the operating element actuation device 110d must be aligned over the relevant operating element of the operating panel 102a in such a way that the operating element 118 is positioned exactly over the operating element to be actuated. In this position, the housing 116 is then connected to the control panel 102a.

In the variant of an actuator 110d shown in Fig. 4, it is attached to a substrate, for example the surface of an operating panel 102a of machine tool 102 by means of permanent magnets 124, which are attached to the underside of feet 120, for example in corresponding recesses in the underside of feet 120 are held (see Fig. 5). In order to enable simple removal or dismantling of the actuator 110d, fastening shoes 126 are provided, which can be firmly connected to the ground with their underside, for example by gluing or screwing. In an upper area, the fastening shoes 126 have recesses into which the lower areas of the feet 120 can be inserted. The recesses are like this designed that the feet are fixed against lateral displacement. The fastening shoes can consist of a ferromagnetic material in order to ensure the highest possible fastening force between the magnets 124 and the feet 120 firmly connected thereto. However, the bottom of the cup-shaped fastening shoes 126 can also be designed in another variant, in which the material of the fastening shoes 126 is not ferromagnetic and consists of plastic, for example, such that a sufficient fastening force results in this case as well.

FIG. 5 shows the actuator 110d in a position in which the feet 124 of the actuator are released from the mounting shoes 126 or lifted off them. The variant of an actuator 110d shown in Figures 4 and 5 thus enables the actuator to be easily attached to the substrate, for example by gluing the fastening shoes 126 to the ground, and the actuator to be dismantled by simply lifting the actuator 110d out of the fastening shoes 126, the stay connected to the ground. Nevertheless, the actuator 110d is sufficiently firmly connected to the substructure by means of the fastening shoes 126 and, in particular, is secured against lateral displacement. The lifting of the actuator 110d makes it possible, if necessary, to manually actuate the actuating element, which is usually actuated by the actuator 110d, in a simple manner. Of course, this also applies to other actuating elements that are covered by the actuator 110d in its installed position.

The embodiment shown in FIG. 4 has a WLAN module 122 which also includes an antenna (not shown in detail) which is arranged in the housing 116 . Such a wireless connection can, of course, also be provided for each differently designed actuator 110 or also for each sensor 112 .

As already mentioned above, a sensor is also arranged in the housing of the actuator 110d, which is designed to detect whether the control element in question has a specific status. For example, the operating element can be designed as an illuminated push button, with the lighting being active when the push button can/must be pressed, for example in order to trigger a machining cycle of the machine tool 102 . The sensor in this case is considered optical sensor trained. Of course, the sensor can also be designed to detect the status of another display element of the control panel 102a and, possibly depending on this, to trigger an action, for example pressing an assigned button or actuating an assigned switch.

The sensors can of course also be designed in any other way. An optical sensor can also be designed as a camera, which detects a display or any other display of a control panel (e.g. error displays using LEDs or other lighting means) or a status of any other element of the machine tool. Using image evaluation methods (including an OCR method), the control unit 106 can determine the required sensor information from the sensor signal supplied to it (in this case the image signal from the camera), for example the request for a specific tool on a screen in plain text or as a symbol for an operator, and depending on this, control the robot 108 and/or the actuators 110 in a suitable manner. It is also conceivable that any information on the screen or the control panel 102a of the machine tool 102 is recognized by a sensor 112 embodied as a camera and is transmitted, in particular streamed, to one or more other participants in a network who are in the same network, such as the automated machine tool 102 or the overall system 100.

The sensors 112 can be designed in such a way that they only transmit the pure sensor signal to the control unit 106, in which case the control unit 106 evaluates the sensor signal, for example examining it for specific characteristic events. Alternatively, the sensors 112 can also be designed in such a way that they have a certain intelligence and, in particular, process the directly detected sensor signal to a high degree. In this case, the sensors can already transmit specific information, for example as digital information, to the control unit. For example, an optical sensor 112 can be designed to recognize the color of a display LED and to transmit the relevant information—for example “RED”, “GREEN”, “YELLOW”—to the control unit 106 . The robot 108 and the actuators 110 and sensors 112 can be in communication with the control unit 106 in any manner. While a wired connection is also possible for the connection to the robot 108, a wireless connection is preferably used for the connection between the sensors 112 and the actuators 110 and the control unit 106. This achieves significantly greater flexibility, and the costs associated with cabling can be saved. In the case of actuators that are positioned in the machining space of the machine tool 102, it would also be difficult to route the cabling in question to the outside. If the actuators are also arranged on moving elements, for example a rotary/pivoting table of the machine tool 102, then a complex and cost-intensive rotary feedthrough would also be required. Of course, a wired connection to the control unit 106 can also be used for the sensors 112 and actuators 110 if this is necessary or advantageous for whatever reason.

The control unit 106 can also be arranged in or on the robot 108 and also integrated with the control unit of the robot 81 . Of course, the control unit 106 can also be provided at any other location, for example in a control station for the automated machine tool or a control station for a plurality of automated machine tools.

The actuators 110 and sensors 112 can in particular also be embodied as autonomous modules, with such a module also being able to comprise a plurality of actuators 110 and/or sensors 112. For this purpose, the relevant module can have its own energy supply, for example a rechargeable battery. Instead of a rechargeable battery, a replaceable battery can of course also be provided.

Instead of or in addition to an electrical energy supply, a pressure energy supply, in particular a pneumatic energy supply, can also be provided. For example, a pneumatically operating actuator 110 can have a pressure reservoir, which can also be designed to be rechargeable. For this purpose, for example, the actuator can have a pressure connection to which, for example by means of the arm 108a of the robot 108, compressed air can be supplied, for example by means of a compressed air lance which is inserted into the compressed air connection. Such variants are particularly suitable for actuators 110, which are designed as pneumatic clamping devices, for example in the form of the vice 110a or the zero-point clamping system 110b.

Finally, it should be pointed out that the actuators 110, in particular the actuators designed as a control element actuating device 110d, can be arranged at any point on the machine tool to be automated or on a component connected thereto, at which a required action must be triggered. For example, a control element actuation device 110d can also be positioned on an existing door opener module if an actuation element, e.g. an electrical switch, is provided on it to trigger the desired door movement.

The same also applies to sensors 112. These can also be arranged at any point on the machine tool to be automated or on a component connected thereto, at which a parameter or piece of information that is required for automating the machine tool has to be recorded is.

The control unit 106 can be implemented in the usual way as a combination of hardware and software, the software being used in particular for evaluating the sensor signals or the information supplied by the sensors and for triggering the functions of the actuators as a function of predetermined parameters which are also derived from the sensor signals can be determined, can be formed. The software can be permanently stored in the control unit 106, also in whole or in part in the form of firmware, or can be made accessible to the control unit 106 for running in it by means of an external memory (including a cloud memory). Finally, it is also possible to run the software in a higher-level control unit and only feed it the signals and/or information supplied by the sensors and to feed the control signals supplied by the higher-level control unit to a local control unit, for example provided in robot 108, which connected to the sensors and actuators. Reference List

100 complete system of automation system and machine tool

102 machine tool

102a control panel

104 automation system

106 control unit

108 external device/robot

108a arm

110 actuator

110a vise

110b zero-point clamping system

110c door opening device

110d control actuator

112 sensors

114 door

116 housing

118 actuator

120 feet

122 WiFi module

124 magnets

126 fastening shoe

Claims

Patent claims System for automating a machine tool,

(a) with an external device (108) for feeding workpieces and/or tools to and/or removing workpieces and/or tools from the machine tool (102),

(b) with at least one actuator (110) for actuating a component of the machine tool (102) and/or at least one sensor (112) for detecting at least one signal of a display component (102a) or a state of the machine tool (102) or the external device (108), and

(c) with a control unit (106) which is designed to trigger at least one function of the machine tool (102) or the external device by controlling the at least one actuator (110) and/or at least one function of the external device (108) trigger depending on a signal from the at least one sensor (112). System according to Claim 1, characterized in that the at least one actuator (110) and/or the at least one sensor (112) is connected wirelessly to the control unit (106). System according to Claim 1 or 2, characterized in that the at least one actuator (110) is designed as an operating element actuating device (110d) and has at least one electrically, pneumatically or hydraulically driven actuating element (118). System according to one of the preceding claims, characterized in that the actuator (110) is designed as a door opener device (110c) for a single or double door (114) of the machine tool (102). System according to one of the preceding claims, characterized in that the actuator (110) is designed as a clamping device (110a, 110b) for use in the machine tool (102). System according to one of the preceding claims, characterized in that the at least one sensor (112) is designed as an optical sensor, for example as a photodiode or camera. System according to one of the preceding claims, characterized in that the at least one sensor (112) and/or the at least one actuator (110) can be connected, for example glued, to the machine tool (102), in particular an operating panel (102a) or a housing of the machine tool or screwed, is formed. System according to Claim 5 or Claims 6 or 7, insofar as these also refer back to Claim 5, characterized in that the at least one sensor is designed to monitor the clamping force or a correct clamping state of the clamping device (110a, 110b). System according to one of the preceding claims, characterized in that selected sensors (112) and actuators (110) or all of them are self-sufficient and have their own, in particular rechargeable, energy supply. System according to one of the preceding claims, characterized in that the external device (108) as a stationary device with at least one movable arm (108a) for the feeding of workpieces and / or tools to and / or removing workpieces and / or tools from the machine tool (102) is formed. System according to one of the preceding claims, characterized in that the control unit (106) comprises a computer program which, when running in the control unit (106), is designed to communicate with the external device (108) and the at least one actuator (110) , possibly under 18

Taking into account the information provided by the at least one sensor (112), to be controlled in such a way that the sequence of processes of the machine tool (102) is automated, in particular the starting of a machining sequence for a workpiece, the opening or closing of a door (114) of the machine tool (102), the removal of a partially or fully finished workpiece or the feeding of a workpiece to be machined and the removal or feeding of tools into the machine tool (102). System according to one of the preceding claims, characterized in that the control unit (106) is designed as an independent, higher-level control unit which is separate from the external device (108) and the machine tool (102) and is connected to the external device (108) and to the at least one actuator (110) and/or the at least one sensor (112) is connected, preferably by a wireless connection. Computer program product, recorded on a data carrier or downloadable from the Internet, for a system (100) according to any one of the preceding claims, which includes commands to trigger the at least one function of the machine tool (102) by controlling the at least one actuator (110) and / or to trigger at least one function of the external device (108) depending on a signal from the at least one sensor (112). Actuator for a system according to one of Claims 1 to 12, characterized in that the at least one actuator (110) is designed to be self-sufficient and for this purpose has its own, in particular rechargeable, energy supply and for wireless communication with the control unit (106) of the system (100) is trained. Sensor for a system according to any one of claims 1 to 12, characterized in that the sensor (112) is self-sufficient and for this purpose has its own, in particular rechargeable energy supply and for 19 wireless communication with the control unit (106) of the system (100) is formed.