WO2020114919A1

WO2020114919A1 - Automated measuring device for a tool-clamping device

Info

Publication number: WO2020114919A1
Application number: PCT/EP2019/083202
Authority: WO
Inventors: Stefan Kempter; Christian Neubauer; Andreas Dolpp
Original assignee: Röhm Gmbh
Priority date: 2018-12-03
Filing date: 2019-12-01
Publication date: 2020-06-11
Also published as: DE102018130730A1

Abstract

The invention relates to a measuring device (1) for inserting into a tool receptacle (6) of a tool-clamping device (5), comprising a measuring body (2), and a control and capturing unit, which is in contact with a voltage source and with a sensor unit for capturing a measured value of a measurement variable. An adjustable element (10) is arranged in the measuring body (2), which adjustable element can be adjusted into an activation position, in which the energy draw from the voltage source for supplying the sensor unit and the control and capturing unit can be activated, and/or into a measuring position for capturing the measured value of a measurement variable by means of the control and capturing unit and by means of the sensor unit.

Description

AUTOMATED MEASURING DEVICE FOR ONE

TOOL CLAMP

The invention relates to a measuring device for insertion into a

Tool holder of a tool clamping device, with a

Measuring body, and with a voltage source and with a sensor unit for acquiring a measured value of a measured variable in contact with the control and acquisition unit.

Furthermore, the invention relates to a method for acquiring a measured value of a measured variable by means of a measuring device.

Such measuring devices and methods are known from the prior art, for example from DE 10 2010 01 8706 B4, in which one

Measuring device for measuring the clamping force of a

Tool clamping device is described. A time measuring unit is assigned to the measuring device, which switches the voltage source from a deactivated to an activated state. One of the

The receiving unit assigned to the measuring device is switched on at periodic intervals in order to determine whether a measurement should be carried out. This periodic switching on and off of the receiving unit but requires a lot of energy from the energy storage, the life of which is considerably reduced. This can also mean that a measurement cannot be carried out due to the insufficient charge level of the energy store and the production is thereby hindered. The object of the present invention is a more energy efficient

To provide measuring device and a more energy-efficient method by means of which an extended service life of the measuring device can be achieved.

The task relating to the measuring device is achieved in the case of a measuring device of the type mentioned at the outset in that a

An adjusting element is arranged, which is adjustable into an activation position, in which the removal of energy from the voltage source for supplying the sensor unit and the control and detection unit can be activated, and / or into a measurement position for recording the measured value of a

Measured variable through the control and registration unit and through the

Sensor unit.

Because the adjusting element can be adjusted into an activation position, energy-efficient activation can take place if necessary. A periodic, energy-intensive query is therefore unnecessary. The control and recording unit controls the measuring process and thus records the measured value of a measured variable. The sensor unit is preferably designed as a strain gauge and / or as a distance sensor and / or as

Piston rod sensor. In the context of the invention, the voltage source is formed as an accumulator or as a battery. In addition, the adjusting member is preferably formed as a piston with a piston rod or as a bolt. In the context of the invention, it is advantageous that the measuring body has a collar at one end - that is to say a hollow cylinder open on one side - in which the adjusting member is guided and that the adjusting member is positioned in the collar in such a way that it can be acted upon by a component of the tool clamping device. This creates a mechanical solution for adjusting the

Adjustment member enables that does not require additional energy supply by the voltage source. The component can be formed as one arranged in the tool holder of the tool clamping device

Clamping head, or as a spindle or as one on a spindle of the

Tool clamping device formed pressure piece or the like. The actuating element is preferably acted upon by the

Contact the component with the adjusting element.

To display the determined measured value, it is advantageous if a display unit that is in contact with the control and detection unit is arranged on the handle and / or on the measuring body. As an alternative or in addition, it is provided that the tool clamping device has a

Display device for displaying the measured value is assigned.

To transfer the measured value to the display unit or the

The display device provides that a transmitter is assigned to the sensor unit or the control and detection unit. The measurement value is preferably transmitted wirelessly via radio, in particular via Bluetooth. If the display unit is integrated directly in the measuring body, radio transmission is not necessary.

In order to further reduce the energy consumption from the voltage source, it is particularly advantageous if a spring is attached to the adjusting element

Adjustment to the measuring position by means of the spring Adjusting element is assigned to the exerted restoring force. The adjustment element is adjusted to the measurement position in a preferred manner

Embodiment only through the restoring force of the spring. In an alternative embodiment, the adjustment can also be carried out only partially by the restoring force of the spring. In a preferred one

Embodiment is arranged around a part of the piston rod of the adjusting element formed as a piston, a spiral spring.

To deactivate the removal of energy from the voltage source, it is provided that the control and recording unit is assigned a timer or a delay unit. It can in the tax and

A measurement duration can be stored, after which the measuring device is automatically deactivated. This also increases the

Energy efficiency of the measuring device

As an alternative or in addition, it is provided that the adjusting element can be adjusted into a deactivation position in which the energy removal from the voltage source for supplying the sensor unit and the control recording unit can be deactivated. The adjustment of the adjustment element in the deactivation position can either be carried out via a timer or delay unit and / or is initiated by a signal to the control and detection unit when the adjustment element is adjusted.

Alternatively, the re-adjustment of the adjusting member in the

Activation position, i.e. the application of the actuator enable deactivation of the energy consumption.

The object relating to the method is achieved by a method for acquiring a measured value of a measured variable in a tool holder of a tool clamping device having a pressure piece a measuring device, the one measuring body and one with a

Has voltage source and a sensor unit in contact with the control and detection unit and with an adjusting element arranged in the measuring body comprising the following steps:

A) inserting the measuring device into the tool holder

Tool chuck;

B) adjusting the adjusting member in an activation position by the pressure piece and thus activation of the energy withdrawal from the

Power source for supplying the sensor, as well as the control and detection unit;

C) clamping the measuring device in the tool clamping device and adjusting the adjusting member connected thereto in a measuring position;

D) measurement of the measured value of a measured variable by means of the sensor unit;

E) transmission of the measured value to the control and recording unit;

F) loosening the measuring device;

G) Removing the measuring device from the tool holder.

This provides an activation of the measuring device that does not require any additional energy from the voltage source. A

energy-intensive periodic polling is no longer necessary. The

The service life of the voltage source can thereby be extended and the measuring device can be used longer. The adjustment of the adjusting member in the activation position is preferably carried out by contacting the pressure piece, whereby the adjusting member is acted upon. It may also be sufficient if only a part of the part of the adjusting member facing the pressure piece contacts the pressure piece. In an alternative embodiment, the loading may e.g. the adjustment of the

Actuator in the activation position also over others in the

Tool clamping device trained components such as the spindle or Clamping head or the like take place. The order of the process steps does not have to strictly follow the list; so steps A) and B) can take place together and also step E) can only be carried out after G).

The adjustment of the adjusting member into a measuring position is preferably carried out by a spring assigned to the adjusting member. Due to the restoring force of the spring acting on the adjusting element during the clamping process by the tool clamping device, the adjustment takes place in the

Measuring position.

To display the measured value, at least step D) is provided as follows:

- Display of the measured value via the control and recording unit on a display unit formed on the measuring body or handle and / or

- Transfer the measured value via a in the control and

Detection unit trained transmitter to one of the

Tool clamping device associated display device or directly higher-level machine control. As a result, the measured value can be displayed either on the measuring device itself and / or on the tool clamping device. Furthermore, the measured value can also be displayed on an external display device provided for this purpose via the transmitter.

Furthermore, it is preferred if step A) is carried out automatically by gripping the measuring device, by means of a tool changer from a tool magazine and inserting it into the tool holder

Tool clamping device and that step G) takes place automatically by removing the measuring device from the tool holder by means of the Tool changer and insertion or storage in the tool magazine. This speeds up the measuring process considerably and enables wear to be checked regularly in order to avoid failures of the tool clamping device. To avoid measurement errors and to determine the

Measured value of the measured variable, it is preferred if step D) is carried out several times and that at least step D) is followed by the step:

- Forming an average of the large number of measured values by the control and recording unit. In particular, it is provided that in the measuring position a pull-in force of a spindle assigned to the tool clamping device and / or a stroke of the pressure piece is determined as the measured variable.

To check the charge level of the voltage source, it is particularly preferred if the current charge level of the voltage source is determined and if the charge level is sent to the display unit and / or the

Display device is transmitted.

To improve energy efficiency, it is envisaged that after

Transmission of the measured value to the display unit or the

Display device the step follows:

- Deactivation of energy consumption from the voltage source

Supply of the control and registration unit as well as the sensor unit. Alternatively, the deactivation of the energy consumption can also take place via a timer assigned to the control and recording unit, which leads to the automatic deactivation of the energy extraction and thus to the deactivation of the measuring device after a predetermined time. As an alternative or in addition, the following step is provided:

- Adjustment of the adjusting member in a deactivation position in which the energy withdrawal from the voltage source for supplying the control and detection unit and the sensor unit is deactivated. The

Deactivation position can be in one embodiment with the

Activation position match, so that the deactivation of the

Energy withdrawal and thus the measuring device takes place with the release process of the measuring device from the tool clamping device.

The invention is explained in more detail below using an exemplary embodiment shown in the drawings; show it:

1 is a perspective view of the first measuring device,

2 is a partially sectioned view of the first measuring device and the corresponding part of the tool clamping device,

Fig. 3 shows a detail of a longitudinal section of the first

Measuring device and the tool clamping device in the released state,

Fig. 4 shows a detail of a longitudinal section of the first

Measuring device and the tool clamping device in the activation position, Fig. 5 shows a section of a longitudinal section of the first

Measuring device in the tool holder in the measuring position, 6 is a partially sectioned view of the measuring device and the corresponding part of the tool clamping device; shown in the measurement position,

Fig. 7 is a diagram of the sequence of the method according to the invention with combined pull-in force and flub measurement and

Fig. 8 is a diagram of the inventive method with a

Flub measurement.

1 shows a perspective view of the measuring device 1 with a measuring body 2 which has a handle 3 at one end and a collar 4 at the other end for receiving in a tool holder 6 of a tool clamping device 5.

FIG. 2 shows a partial section of the measuring device 1 from FIG. 1 and a partially cut fragment of a spindle 7 of the tool clamping device 5, which has a pressure piece 8 at the end facing the measuring device 1. In the measuring body 2 is in the collar 4 as a piston 9 with a

Piston rod 11 formed adjusting member 10 out. The piston rod 11 is partially surrounded by a spring 12 formed as a spiral spring. Arranged in the handle 3 of the measuring device 1 is a voltage source, not shown, which is formed as an accumulator or as a battery. In addition, a control and not shown in the measuring body 2

Arranged detection unit which is in contact with the voltage source and with a force measuring system, for example as a

Strain gauge sensor (DMS) formed, not shown

Sensor unit. The control and detection unit has a display unit 13 formed on the handle 3. Alternatively or in addition, it can also on the tool clamping device 5 a not shown

Display device be formed so that a transmitter, not shown, can also transmit the measured value to the display device. The control and detection unit serves to control the measurement process of the measured variable by the sensor unit, in the present exemplary embodiment to determine the pull-in force or the clamping force. Optionally, the control and detection unit can also include an evaluation unit, with the aid of which the measured value or, in the case of a plurality of measurement processes, an average value can be formed from the individual measured values. 3 to 5 and the schematic representations of FIGS. 7 and 8, the method according to the invention, i.e. the activation, the measuring process and the deactivation of the measuring device can be followed. First, the measuring device 1 is automatically brought into the machining center from a tool magazine (not shown) by a tool changer (not shown). The measuring device 1 is deactivated, i. H. there is no energy withdrawal from the energy store.

The measuring device 1 is in the tool holder 6

Tool clamping device introduced. Here, the piston 9 of the measuring device 1 and a component 14 of the tool clamping device 5, namely the pressure piece 8, as shown in FIG. 4 contact. The pressure piece 8 acts on the piston 9 so that a force acting against the spring force of the spring 12 is exerted on the piston 9. The piston 9 is moved in the direction of the spring 12 into the activation position, the spring 12 being compressed. In the activation position, the energy withdrawal from the voltage source for supplying the sensor unit and the control and registration unit activated. The activation position is recognized by positive edge detection.

The measuring device is then clamped in the tool clamping device 5. The pressure piece 8 is adjusted against the direction of the piston 9. 5 shows, the piston 9 due to the restoring force

Spring 12 adjusted to the measuring position. The electronics of the control and

The registration unit is started up with the activation position beginning and the control and registration unit controls the execution of a predefined number of measurements of a measured variable in the latter

Embodiment the pull-in force of the tool clamping device 5. The pull-in force is determined by the elongation of the strain gauges

Sensor unit measured and recorded by the control and registration unit. The measured values determined in this way are transmitted via the control and

Detection unit wirelessly transmitted to the display unit 13 or the display device via a radio link. At the same time, the

The state of charge of the voltage source is determined and transmitted to the display unit 13 and / or the display device. The measuring device 1 is released. The piston 9 is moved back into the activation position. From the plurality of measurements, an average value can either be determined by the control and detection unit, which includes an evaluation unit formed as a microcontroller, or the average value is determined in an evaluation unit assigned to the tool clamping device 5. In the second case, the energy consumption is deactivated from the

Voltage source following data transmission i.e. by repositioning the piston 9 into the activation position, which is now a deactivation position. In the first case, the tax and

Detection unit assigned a timer, not shown, so that the Deactivation of the energy consumption takes place automatically after a time previously stored in the control and recording unit.

Alternatively or in addition, it is possible to determine not only the pull-in force by the measuring device 1, but also the stroke of the pressure piece 8 at the same time, in order to draw conclusions about the wear of the

To be able to pull tool clamping device 5. Here, as shown in FIG. 6, the length of the adjusting member 10 formed as a piston 9 is at least as long as the maximum executable stroke of the pressure piece 8. The display unit 13 or the display device is assigned a control panel 15 in which a stroke measurement or a Pull-in force measurement can be selected. The sensor unit also has a displacement measuring system such as a piston rod sensor or a

Distance sensor on. The measurement is carried out analogously to the procedure for determining the pull-in force described above. The control and detection unit and / or the evaluation unit can infer the stroke of the pressure element 8 from the distance between the adjusting member 10 and the pressure element 8. An extension of the stroke is the first sign of wear and tear, while an insufficient lubrication can be inferred from a reduction in the stroke. The measured values are recorded independently of one another and can also be displayed simultaneously. The combination of pull-in force and stroke is a good indicator of wear.

Another special feature is that the pull-in force measurement and / or the stroke measurement can be carried out with rotation. The measurements can be made at different speeds and / or

Spindle accelerations and / or spindle brakes take place, as shown in FIG. 8 clarifies. In addition, the method as shown in FIG. 7 can include control steps: after the sensor units have been acted on, ie after the adjustment member 10 has been moved into the measurement position, the control and detection unit checks whether the adjustment has taken place. If this is not the case, the measuring device 1 is deactivated, ie the energy consumption is deactivated. If, on the other hand, the adjustment has taken place, the measured values are determined after a short dwell time for booting electronics of the control and recording unit that control the measuring process. Furthermore, after the mean value has been transmitted to the display unit 13, a further step is queried as to whether the transmission was successful.

REFERENCE SIGN LIST

1 measuring device

2 measuring bodies

3 handle

4 fret

5 tool clamping device

6 tool holder

7 spindle

8 pressure piece

9 pistons

10 adjusting element

11 piston rod

12 spring

13 display unit

14 component

15 Control panel

Claims

PATENT CLAIMS

1. Measuring device (1) for insertion into a tool holder (6) of a tool clamping device (5), with a measuring body (2), and with a voltage source and with a sensor unit for detecting a measured value of a measured variable in contact with control and

Detection unit, characterized in that an adjusting member (10) is arranged in the measuring body (1), which is adjustable in one

Activation position in which the energy withdrawal from the

Voltage source for supplying the sensor unit and the control and detection unit can be activated and / or in a measuring position for detecting the measured value of a measured variable by the control and

Registration unit and by the sensor unit.

2. Measuring device (1) according to claim 1, characterized in that the measuring body (2) has at one end a collar (4) in which the

Adjusting member (10) is guided and that the adjusting member (10) is positioned in the collar (4) in such a way that it is supported by a component (14)

Tool clamping device (5) can be acted upon.

3. Measuring device (1) according to claim 1 or 2, characterized in that on the handle (3) and / or on the measuring body (2) a display unit (13) in contact with the control and detection unit is arranged to display the determined measured value .

4. Measuring device (1) according to claim 3, characterized in that the sensor unit or the control and detection unit is assigned a transmitter for transmitting the measured value to an external display device or a machine control.

5. Measuring device (1) according to one of claims 1 to 4, characterized in that the adjusting member (10) is assigned a resilient element (12) for adjustment in the measuring position by means of the spring (12) on the adjusting member (10) exerted restoring force.

6. Measuring device (1) according to one of claims 1 to 5, characterized

characterized in that the control and recording unit is assigned a timer for deactivating the removal of energy from the

Voltage source.

7. Measuring device (1) according to one of claims 1 to 6, characterized

characterized in that the adjusting member (10) is adjustable in a

Deactivation position in which the energy withdrawal from the

Voltage source for supplying the sensor unit and the control and detection unit can be deactivated.

8. Method for acquiring a measured value of a measured variable in a tool holder (6) having a pressure piece (8)

Tool clamping device (5) by means of a measuring device (1), which has a measuring body (2) and a control and detection unit in contact with a voltage source and a sensor unit and with an adjusting member (10) arranged in the measuring body (2), comprising the following steps :

A) inserting the measuring device (1) into the tool holder (6) of a tool clamping device (5);

B) adjusting the adjusting member (10) into an activation position by the pressure piece (8) and thus activating the energy extraction the voltage source for supplying the sensor unit as well as the control and detection unit;

C) clamping the measuring device (1) in the tool clamping device (5) and adjusting the adjusting member (10) in a measuring position connected therewith;

E) transmission of the measured value to the control and recording unit;

F) loosening the measuring device (1);

G) Removing the measuring device (1) from the tool holder (6).

9. The method according to claim 8, characterized by the at least step D) following step:

- Transfer the measured value, the control and detection unit to a display unit (13) and / or formed on the measuring body (2) or handle (3)

- Transfer the measured value via a in the control and

Detection unit trained transmitter to one of the

Tool clamping device (5) associated display device or directly higher-level machine control.

10. The method according to claim 8 or 9, characterized in that step

A) takes place automatically by gripping the measuring device (1) by means of a tool changer from a tool magazine and inserting it into the tool holder (6) of the tool clamping device (5) and step G) is carried out automatically by removing the measuring device (1) from the tool holder (6) by means of the tool changer and

Inserting or depositing in the tool magazine.

11. The method according to any one of claims 8 to 10, characterized in that step D) is carried out several times and that at least step D) is followed by the step:

- Forming an average of the large number of measured values by the control and recording unit.

12. The method according to any one of claims 8 to 11, characterized in that in the measuring position a pull-in force of a spindle (7) assigned to the tool clamping device (5) and / or a stroke of the pressure piece (8) is determined as the measured variable.

13. The method according to any one of claims 9 to 12, characterized by the

Steps:

- Determination of a current charge level of the voltage source, and

- Transmission of the charge level to the display unit (13) and / or the display device.

14. The method according to any one of claims 9 to 13, characterized in that after transmission of the measured value to the display unit (13) or the display device, the step follows:

- Deactivation of the energy withdrawal from the voltage source for supplying the control and detection unit and the sensor unit 15. Method according to one of claims 9 to 13, characterized by the following step:

- Adjusting the adjusting member (10) to a deactivation position in which the energy withdrawal from the voltage source for supplying the control and detection unit and the sensor unit is deactivated.