DE102020103986A1 - Device for calibration - Google Patents

Abstract

The invention relates to a device for calibrating a dynamometer, in particular a test bench, preferably a plate test bench, comprising a frame with a fixing device for the dynamometer, a force generating device mounted movably relative to the frame for applying a force to the dynamometer, the force generating device having a force application device and a force applying device and a reference sensor arranged between the force application device and the force application device.

Description

The invention relates to a device, a system and a method for calibrating a force gauge, in particular a test stand, preferably a plate test stand, for example for motor vehicles.

In test stands, e.g. plate test stands, for motor vehicles such as motorcycles, cars, buses and / or trucks, forces are measured which act on the tire contact areas during acceleration and / or braking, i.e. during negative acceleration.

Force gauges are used to measure the forces. These are usually built into the test bench. A calibration takes place in the installed state. However, this is associated with a high expenditure of time and thus high costs.

It is therefore an object of the invention to create a device for calibrating a force gauge, a system and a method for calibration, which enables quick and inexpensive calibration.

This problem is solved by the subject matter and the method of the independent claims.

The calibration device according to the invention calibrates a force gauge, in particular a test stand, preferably a plate test stand. The test stand is designed, for example, as a motor vehicle test stand.

During the test, the force gauge is arranged in the test stand and measures the forces that occur.

Alternatively, the dynamometer can also be used, for example, on a scale.

To ensure that the dynamometer is working correctly, it must be calibrated at certain time intervals.

The dynamometer is preferably designed to be elongated.

The force meter can in particular be designed as a shear force sensor, preferably a double shear force sensor. The force gauge can have at least one sensor, preferably two, three, four, five or more sensors. The sensor can in particular be designed as a strain gauge.

The device for calibrating has a frame with a fixing device for the dynamometer. The frame can in particular have a rectangular shape. For example, the size can be compact. In particular, the length and / or width can be between 10 cm and 100 cm, preferably between 30 cm and 60 cm, e.g. 50 cm. The height can for example be between 1 cm and 25 cm, preferably between 5 cm and 15 cm.

The fixing device is in particular rigidly connected to the rest of the frame or forms a unit with it.

The dynamometer can in particular be fixed to the fixing device without tools. The dynamometer is preferably placed or plugged onto the fixing device. In particular, screwing is not necessary. The dynamometer and the fixing device are in particular in engagement with one another.

There is preferably a certain amount of play or the dynamometer is fixed in a floating manner. The handling, in particular the fixing and / or releasing, of the dynamometer from the fixing device is made easier as a result.

To a certain extent, the fixing device simulates the same situation as a test stand. It was surprising that in this way the force gauge can be calibrated outside the test bench under the same conditions as in the test bench. The installation situation of the force sensor in the calibration device corresponds to the installation situation in the test bench.

The device also has a force-generating device, mounted movably relative to the frame, for applying a force to the dynamometer. The force generating device comprises a force application device and a force application device. In particular, the force introduction device generates a force and / or introduces the force into the calibration device.

The force introduction device can in particular be actuated manually. In particular, the force can be generated manually, for example by means of a spindle, e.g. a ball screw. Alternatively or additionally, the force can be generated hydraulically and / or pneumatically. A manual force application device can also be supported hydraulically and / or pneumatically, for example.

Alternatively, a motorized, in particular an electromotive, force introduction device is conceivable. For example, a servomotor and / or a gear can be provided. For example, a spindle, in particular a ball screw, are driven. The calibration can in particular take place partially or fully automatically.

For calibration, forces between 0.1 kN and 20 kN, preferably between 5 kN and 15 kN, e.g. 10 kN, can be introduced. For example, different forces can be set or approached one after the other for calibration.

The force application device forwards the force introduced into the calibration device and / or applies this force to the dynamometer. The force application device is preferably directly connected to the dynamometer.

In particular, the dynamometer is held in the fixing device while the force application device presses on the dynamometer and exerts a force. The dynamometer deforms in the process. The corresponding force is measured as an actual value by the force meter's sensor.

A reference sensor is arranged between the force application device and the force application device. The reference sensor has, in particular, a strain gauge.

The reference sensor measures the force generated by the force application device as a setpoint value. The dynamometer is connected in series for this purpose. The actual value of the force meter can be calibrated to the target value of the reference sensor.

The dynamometer is removed from the test stand for calibration and inserted into the calibration device. The calibration device therefore does not first have to be installed on the test bench in a complex manner. This makes the calibration much faster and more cost-effective than previous calibration methods.

Further developments of the invention can also be found in the dependent claims, the description and the accompanying drawings.

According to one embodiment, the fixing device has at least one fixing pin, preferably at least two fixing pins.

Precisely two fixing pins are particularly preferably provided. An elongated dynamometer can in particular be held at both end regions.

With at least two fixing pins, twisting of the dynamometer is reliably prevented.

More than two fixing pins, e.g. three, four, five, six or more, can also be provided.

The fixing pins can in particular have a cylindrical shape. These preferably have a round cross section.

Alternatively, a different cross-section, e.g. an oval or rectangle, is conceivable. This is particularly advantageous when only a single fixing pin is provided. Rotation of the dynamometer can also be prevented by the shape of the fixing pin.

The dynamometer is fixed, for example, attached to the at least one fixing pin, preferably without tools.

This enables quick assembly and disassembly.

According to a further embodiment, the force application device has at least one, preferably exactly one, application pin.

The application pin is in particular rigidly connected to the force application device or forms part of it.

The application pin is preferably arranged centrally between two fixing pins. In this way, the dynamometer can be held at both ends while a force is applied to it in the middle.

According to a further embodiment, the force application device, the force application device and / or the reference sensor is mounted by means of a spherical socket-spherical nut connection.

In particular, this enables the reference sensor to be fastened quickly to the force application device and / or the force application device. Furthermore, the force is passed on in particular without loss.

According to a further embodiment, a further force-generating device and a further reference sensor are provided on a side of the force-generating device opposite with respect to the fixing device.

The further force generating device has in particular a further force introduction device and / or a further force application device. In particular, a common force application device, eg a common application pin can be provided. In particular, a force can be applied to the dynamometer from both sides. For example, tensile and compressive forces are conceivable.

The further reference sensor is arranged in particular between the further force application device and the force application device.

The invention also relates to the use of the device according to the invention for calibrating a force gauge, in particular a test stand, preferably a plate test stand.

The invention also relates to a system with a calibration device according to the invention and a force gauge. The dynamometer is in particular elongated and / or has at least one sensor, e.g. a strain gauge.

The dynamometer comprises at least one fixing recess for receiving the fixing device, in particular at least one fixing pin, and at least one application recess for receiving the force application device, in particular an application pin.

A plurality of fixing recesses, e.g. two, three, four, five, six or more, are preferably provided.

The fixing recess (s) and the loading recess preferably completely penetrate the dynamometer. The same recesses are also used for normal test bench operation in the test bench.

For example, a holding plate of a plate test stand can have two fixing pins. The retaining plate is screwed to the floor, for example.

A loading pin can be arranged on a top plate that is movable relative to the holding plate. The dynamometer can be attached to the at least one fixing recess and the loading recess to the at least one fixing pin and the loading pin of the panel test stand. There is preferably a certain amount of play or the dynamometer is fixed in a floating manner. The handling, in particular the fixing and / or loosening of the dynamometer on / from the fixing device, is made easier as a result.

In particular, it is fastened without tools. The dynamometer is preferably not permanently mounted on the plate test bench. The dynamometer can thus be easily removed and inserted into the calibration device, for example.

The invention finally relates to a method for calibrating a force gauge with a calibration device according to the invention or a system according to the invention.

The dynamometer is fixed to at least one fixing recess on the fixing device, in particular at least one fixing pin, and to at least one application recess on the force application device, in particular an application pin.

In particular, for this purpose, the dynamometer is placed on the fixing device at a fixing recess and on the force applying device at the application recess. The pins engage in the recesses.

This corresponds to the same installation situation as in a panel test bench.

A force is then applied to the dynamometer. The force applying device exerts a force on the dynamometer.

The actual force measured by the dynamometer is compared with the target force of the reference sensor and calibrated accordingly.

According to one embodiment, a force is applied centrally to the dynamometer. In particular, the application recess is provided centrally between two fixing recesses.

According to a further embodiment, there is a data connection between the force gauge and a test stand, in particular a plate test stand, during calibration. In this way, data can always be compared during calibration.

The entire calibration can preferably be carried out automatically. In particular, the data transmission and / or control can take place in an automated manner. In this way, the force application device can also be controlled and e.g. approach certain measuring points.

In particular, wired or wireless data transmission can take place. For example, a display can be switched to a calibration mode. The braking forces of the left and right side of a test bench can be transferred.

The invention also relates to a test stand, in particular a plate test stand, with a force gauge and a calibration device according to the invention.

All the embodiments and components of the devices described here are designed in particular to be operated, for example by means of a control device, according to the method described here. Furthermore, all the embodiments of the devices described here and all the embodiments of the method described here can each be combined with one another, in particular also detached from the specific configuration in the context of which they are mentioned.

• 1 eine Schnittansicht einer Ausführungsform eines Plattenprüfstands,
• 2 eine Draufsicht einer Ausführungsform eines Kraftmessers,
• 3 eine Draufsicht einer Ausführungsform einer erfindungsgemäßen Kalibriervorrichtung, und
• 4 eine Draufsicht einer weiteren Ausführungsform einer erfindungsgemäßen Kalibriervorrichtung mit fixiertem Kraftmesser.

The invention is described below by way of example with reference to the drawings. Show it:

• 1 a sectional view of an embodiment of a plate test stand,
• 2 a top view of an embodiment of a dynamometer,
• 3 a plan view of an embodiment of a calibration device according to the invention, and
• 4th a plan view of a further embodiment of a calibration device according to the invention with a fixed force gauge.

First of all, it should be noted that the embodiments shown are purely exemplary in nature. In this way, individual features can be implemented not only in the combination shown, but also on their own or in other technically meaningful combinations. For example, the features of one embodiment can be combined as desired with features of another embodiment. In particular, more or fewer fixing pins, fixing recesses, application pins and / or application recesses can be provided.

If a figure contains a reference number which is not explained in the directly associated descriptive text, reference is made to the corresponding preceding or subsequent explanations in the description of the figures. The same reference numerals are used for the same or comparable components in the figures and these are not explained again.

1 shows one side of a panel test bench 10 with a top plate 12th and a holding plate 14th . The top plate 12th and the holding plate 14th can in particular be magnetically attached. For example, the top plate 12th can be opened, unfolded and / or removed without tools.

With the retaining plate 14th are two fixing pins 16 firmly connected, for example screwed and / or welded.

With the relative to the retaining plate 14th movable top plate 12th is an assignment pin 18th firmly connected, for example welded.

On the fixing pins 16 can an in 2 Force gauge shown 20th be attached. To this end, the dynamometer 20th two fixing recesses 22nd in which the fixing pins 16 can intervene.

Furthermore, the dynamometer 20th one centrally between the two fixing recesses 22nd arranged loading recess 24 on. With the top plate closed 12th the application pin takes effect 18th into the loading recess 24 a.

Does the top plate move during a test process? 12th relative to the holding plate 14th , so deformed, in particular bends, the dynamometer 20th .

Sensors 26th , for example strain gauges, which are arranged in particular in measuring chambers, determine the forces acting and transmit the measured values, in particular to an evaluation device.

Preferably there is in each case between a fixing recess 22nd and the loading recess 24 a sensor 26th intended.

Through the fixing recesses 22nd and the loading recess 24 can the dynamometer 20th for calibration without tools from the panel test bench 10 can be removed. The calibration therefore does not have to take place in the installed state, which is associated with considerable time and thus cost savings.

An in 3 Calibration device shown can be used.

The calibration device comprises a frame 28 with a fixation device 30th for the dynamometer 20th . The fixation device 30th has two fixing pins 16 on which one is firmly attached to the frame 28 are connected.

Relative to the frame 28 is a force generating device 32 to act on the dynamometer 20th mounted movably with a force.

The force generating device 32 has a force application device 34 and a force applying device 36 with an application pin 18th on.

Between the force application device 34 and the force applying device 36 is a reference sensor 38 arranged. This includes, for example, a strain gauge.

If, for example manually, a force is applied to the force application device 34 initiated, determines the reference sensor 38 this target force. Via the application pin 18th is the dynamometer 20th connected in series. Thus, the dynamometer also becomes 20th applied with the same force. The actual value given by the sensors 26th of the dynamometer 20th is determined can now be based on the target value of the reference sensor 38 be calibrated. As indicated by the double arrow, in particular both tensile and compressive forces can be generated.

The calibration device mimics the installation situation of the plate test bench 10 to. Consequently, the dynamometer 20th removed and calibrated in the calibration device. Compared to a calibration in the installed state, the calibration is much less time-consuming.

In the embodiment shown in 4th is shown, force generating devices can be on both sides 32 , 32 ' with force introduction devices 34 , 34 ' and force applying devices 36 , 36 ' be provided. Any force generating device 32 , 32 ' can use a separate reference sensor 38 , 38 ' be assigned.

A common application pin is preferred 18th intended. In particular, there is a common fixing device 30th with fixing pins 16 and / or a common framework 28 intended. Alternatively, different frames can be used 28 be provided.

There is preferably a certain amount of play or the dynamometer 20th is fixed floating. The handling, in particular the fixing and / or loosening of the dynamometer 20th from the fixing device 30th , makes it easier.

The dynamometer 20th can be used during calibration, for example by means of a cable connection or wirelessly, with the test bench 20th be connected. In this way, permanent data synchronization and / or data exchange can take place.

List of reference symbols

10

Plate test bench

12th

Top plate

14th

Retaining plate

16

Fixing pin

18th

Application pin

20th

Dynamometer

22nd

Fixing recess

24

Loading recess

26th

sensor

28

frame

30th

Fixing device

32, 32 '

Force generating device

34, 34 '

Force application device

36, 36 '

Force applying device

38, 38 '

Reference sensor

Claims (10)

Device for calibrating a dynamometer (20), in particular a test bench, preferably a plate test bench (10), comprising a frame (28) with a fixing device (30) for the dynamometer (20), a force generating device (32) mounted movably relative to the frame (28) ) for applying a force to the force gauge (20), the force generating device (32) having a force application device (34) and a force application device (36), as well as a reference sensor (38) arranged between the force application device (34) and the force application device (36) . Device according to Claim 1 , characterized in that the fixing device (30) has at least one fixing pin (16), preferably at least two fixing pins (16). Device according to Claim 1 or 2 , characterized in that the force application device (36) has at least one, preferably exactly one, application pin (18). Device according to one of the preceding claims, characterized in that the force introduction device (34), the force application device (36) and / or the reference sensor (38) is mounted by means of a spherical socket-spherical nut connection. Device according to one of the preceding claims, characterized in that a further force-generating device (32 ') and a further reference sensor (38') are provided on a side of the force-generating device (32) opposite the fixing device (30). Use of the device according to one of the preceding claims for calibrating a force gauge (20), in particular a test stand, preferably a plate test stand (10). System with a device for calibration according to one of the Claims 1 until 5 and a dynamometer (20), wherein the dynamometer (20) has at least one fixing recess (22) for receiving the Fixing device (30), in particular at least one fixing pin (16), and at least one application recess (24) for receiving the force application device (36), in particular an application pin (18). Method for calibrating a force gauge (20) with a device according to one of the Claims 1 until 5 and / or a system Claim 7 , in which the dynamometer (20) on at least one fixing recess (22) on the fixing device (30), in particular at least one fixing pin (16), and on at least one application recess (24) on the force application device (36), in particular one application pin (18 ), is fixed, and the force gauge (20) is subjected to a force. Procedure according to Claim 8 , characterized in that a force is applied centrally to the force gauge (20). Procedure according to Claim 8 or 9 , characterized in that during calibration there is a data connection between the force gauge (20) and a test stand, in particular a plate test stand (10).

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