JPH0213722B2 - - Google Patents

Abstract

Apparatus for checking the dimensional accuracy and/or measuring the dimensions of large objects (1), provided with checking points which serve as or carry suspended measuring scales (2-7) comprises at least one beam-projection unit 12, 20 movable along a guide 8, 9 to emit a narrow beam of light at an angle to the guide. The position of the projector unit is optically or magnetically readable automatically and is stored in the memory of a calculating unit into which measurement data of an undistorted object can also be entered. The projection units 12, 20 also comprise devices for determining beam angle. From measurements on one checking point the apparatus calculates the spatial location of that point and the correct apparatus setting for other points. When the apparatus is set on other points, the correctness of the position of the point is indicated optically or accoustically. <IMAGE>

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for checking or measuring the dimensional accuracy of large objects such as vehicle bodies.

Modern cars with tension shell structures are manufactured in large series with precise precision. The engine, power transmission, front gear and rear gear are fitted more or less directly to the vehicle body on reinforcements or on arms welded to the vehicle body. The functionality of the vehicle is highly dependent on the attachment points, for example the steering devices to the front and rear devices, always being in position and having the appearance intended by the manufacturer.

In a collision event, impact forces often propagate into the vehicle shell, resulting in residual deformation. Without thorough inspection and measurement, it is difficult to determine the location of any deformation, which can have a fatal impact on the vehicle's driving characteristics. Compensation for slight deformations in the bodywork is possible by means of adjustment facilities built into the front device. However, under no circumstances should the mounting position of the device suspension be "moved" by enlarging the bolt hole or the like.

Swedish Patent No. 7103780-8 discloses a device for checking whether a car maintains the correct dimensions for the relevant car model, for example after a collision. The wheel is lifted in a device such as a jig or alignment punch.

The points inside the car used to check the measurements of the car body consist of fixing holes and mounting holes for bolts and bolted connections under the car. In order to be able to form these measuring points, so-called measuring point devices are used, which are attached to all relevant check points in the vehicle body. Inside each measuring point device there is a ruler with a millimeter scale and a running rider that can be preset to a nominal height level. By reading where the light beam hits on a ruler, you can directly measure the height deviation of the vehicle body. By means of reflective color marking, the position of the light beam on the ruler can be easily checked within a range of several meters.

The light comes from a laser that emits a substantially parallel red beam along the longitudinal order. The beam strikes a polarizer, where it is split into two beams at right angles to each other. One beam continues along the aforementioned longitudinal direction, while the other is directed from a perpendicular alignment.
When the movable deflection device is moved along the length, the perpendicular beam is also shifted along the length,
Hits one ruler at a time. The distance between the rulers is then read directly on the rolled-up measuring tape line placed on top, oriented longitudinally.

In this way, all longitudinal and vertical dimensions of the vehicle body are measured. To measure the width dimension, the deflection device is moved to the longitudinal end. The deflection device now emits a beam along the side, where the measurement is carried out in the same way as in the longitudinal direction.

If the cars need to be aligned, the operator can turn the deflection device on each column in succession.
The girder is set to the position where the light beam should normally hit the ruler, according to the data of the related car model. If at any position the beam does not then fall on the relevant ruler, the cars are aligned until this happens.

According to the patent cited here, the measurement takes place by mechanically attaching an indicating device movable along the measuring path at the starting position for the movement.
A measuring tape line, which can be wound up, is attached to an indicating device and read on a deflection device. Among the disadvantages of this design is that the measuring tape must be attached to rollers, pulleys, etc. In addition, the measuring tape can also become abrasive over time. A further disadvantage is that the measuring tape line cannot be recorded electronically.

Improvements in this respect can be made by providing the measuring device according to the invention with the features set out in the claims. Not only can an electronic reader be introduced to provide more reliable readings over time without mechanical wear, but the measured values can also be transmitted electronically to a central reader or the like. It is also possible to calculate data for measurements separately for each deflection device and present these in a visual display, such as a follow-up window on the deflection device.

It is also possible to send the data digitally to a central processing unit such as a microcomputer or minicomputer with a keyboard. In this case, the data about the object being measured can also be presented on a visual display device and/or on a printing press, together with the deviations from the reference value for the object concerned. If the deflection device is additionally provided with a drive motor, the operator can perform the entire measuring device while standing or sitting at the keyboard.

Electronic reading can be done in a variety of ways. Reading of the movement of the deflection device along the girder can occur by means of magnetically recorded information on a steel tape placed along the girder. Information can also be recorded directly on the digits. Optical marking on orders of magnitude with alternating black and white fields and several scanning diodes for fine resolution can be used for this purpose. The deflection device can be equipped with a gear wheel, the rotation of which can be read electronically or electro-optically either directly or via a code disk. Moreover, it is possible to combine several types of these methods. A particularly accurate and reliable distance indication can be achieved by combining magnetic information placed along the beam with optical markings placed at a relatively large distance from each other, for example at a distance of 1 decimeter from each other. can get. These optical markings are used to update a counter that counts each magnetic marking passed by the deflection device.

electronic reading of the distance between the transmitting device can also be achieved in other ways than those described so far. According to one method, the distance can also be determined by ultrasonic distance measurement towards an acoustic plane. Either the reference point or the transmitter can be equipped with an acoustic surface and the other with a range finder. It is also possible to use existing laser beams for distance measurement; in this case, so-called interferometric distance measurement is most appropriate. You can also use winding tape or thread to measure distance.
Alternatively, it is possible to use wheels that run along the girder and are read. The key point of the invention is that distance measurements are converted into electrical signals and signal processed.

Each processing unit, whether in each separate deflection device or in a central unit, is provided with a memory that allows an operator to perform measurements on an object to be measured, such as an automobile. You can enter the reference data of the relevant car model. This memory is arranged in such a way that points in a coordinate system, such as Cartesian coordinates with x, y, z coordinates, can be determined as decisive for the measurement of the object to be measured.
The length and width measurements of related objects are also stored in memory.
For example, this can occur if the operator presses a key that has the correct settings. Measurements are presented in x, y, z coordinates and compared to input reference values. The deviation is presented on a visible “deviation indicator”, e.g. setpoint value,
Shown with actual and derivative values.

The reference values can be entered into the memory by means of magnetic cards, punch cards, optical code readers, etc. of the type used in programmable computers, for example. If a central processing unit is used, input may also be made via a keyboard, cassette tape, floppy desk, etc.

When a central device is used, this is suitably connected to the measurement path by means of data transmission lines or cords.
However, it is entirely possible to have an acoustic or optical transmission. The optical transmission preferably takes place with infrared light, so that the transmission is not interfered with by the light that prevails in the building in which the measurements are taken. The central device is equipped with a keyboard by which the operator can control the measurement operation. If the deflection device is equipped with a drive motor and electronic means for horizontal and vertical internal angle setting, the operator can control the entire measurement operation while standing at the keyboard. One advantage of using a central device is that it is less complex if the deflection device only needs to have a motion indicator and a transmitter for transmitting information, i.e. it does not need to have a computing device. It is from.

In the setup according to Swedish Patent No. 7103780-8, two measuring beams are used, one for measurements in the Y direction and the other for measurements in the X direction. The invention is very well applicable to this setting. However, measurement of the object to be measured can occur simply by using a straight measurement path. in this case,
One or more deflection devices may be used and more than one deflection angle for the measurement path may be used. If a resetting can occur between a normal deflection and a deflection at an angle of 45° to the beam along the measuring column, then both the x- and y-distances of the object to be measured will be
obtained with the same deflection device. If two deflection devices are used, the light can be deflected by both devices simultaneously toward the same measurement point. And since the light is modulated at a frequency that is in a different phase position from the two devices, there will be a frequency and phase difference, and if the point of incidence is visible to the eye, then if it is the beam from one deflection device. If it is hit by only one light source, it is interpreted as flashing, and if it is hit by light beams from two or more devices, it is interpreted as constant light. By this means a very precise alignment towards the measurement point from more than one direction can be achieved. If the deflection device is equipped with a drive motor that can be operated from the keyboard, the operator can easily set it up while standing or sitting at the keyboard. Of course, it is also possible to use this feature even in the case where the devices are moved along the measuring path by a single operator and each of the devices has its own computing device.

The deflection device can also be provided with an adjustable deflection angle, in which case a mirror integrated in the device can be rotated, the rotation of which can be controlled in a manner known per se, for example by a code desk, a differential transformer, etc. , resolver, etc., and can be indicated by a micrometer screw reading.

The information that can be obtained, such as the movement along the measuring path, the rotation of the mirror, the basic data for the position, the angular position of the mirror,
This is sufficient for calculating the distance and width between measurement points of the object to be measured.

In particular, when separate deflection devices are provided with computing devices, they may additionally be provided with acoustic information, so that, for example, an acoustic signal is heard when a set point is reached within a predetermined tolerance level. It can be made so that The acoustic signal may also be pulsed or frequency modulated to provide a more graduated indication of deviation from the set point.

The invention will now be explained in more detail with reference to the accompanying drawings.

Shown in FIG. 1 is a first embodiment of an instrument that checks the measurements and gives the correct indication in case of correct measurements of the vehicle. The car is lifted by a lifting device (not shown). Rulers 2 to 7 are attached to appropriate measurement points under the car 1. These measuring points are placed in different positions on different car models. The measurement points and dimensions for each car model relative to the reference car are specified in a special measurement record.

Two transverse columns 8 and 9 are placed diagonally below the car being pulled up and at a working height suitable for the operator wishing to carry out measurement checks. The longitudinally oriented 8 is placed parallel to the longitudinal axis of the car. A light source 10 is fixedly placed at one end of the girder 8. It is important for the light source to be able to clearly read the impact on one of the rulers when the operator is standing on the girder.
This means that it must be able to emit a narrowly focused beam of light. A He-Ne type laser satisfies these requirements.

Shown above beam 8 are two deflection devices 12, 13 which deflect the light from the laser at right angles to the beam. The device 12 is movable along the girder 8 and the device 13 is permanently placed at the end of the girder 8 abutting the girder 9.

The device 12 projects both a deflected beam and a beam straight ahead. The device 13 deflects the light along digit 8 so that it passes along digit 9, and
Like the light beam from the device 12, it is polarized towards the same landing point on the measuring ruler 2.

Of course, it is also possible according to the invention to use only one deflection device 12 on column 8, and to carry out the measurements of the vehicle in the x and y directions separately in two different stages; In the case, during the measurement in the y direction,
Deflection device 12 is placed in the position shown relative to device 13.

According to the invention, the motion paths, namely digits 8 and 9, are provided with detectable markings along their entire length, which markings can be used for measurements. , and the movable deflection device is equipped with a detector for detecting markings. These markings and detectors may be of different types, such as are known per se. For example, the girder may be fitted along its length with a steel tape wire containing magnetically recorded information, in which case the deflection device is provided with a detection head for picking up the information. ing. The steel tape wire could possibly be removed and the girder itself could be provided with recorded information. Also, on a digit,
Optical markings with alternating white and black fields, e.g. 1 cm long, may be provided, and the deflection device may be equipped with a plurality of scanning diodes, e.g. The scanning device also includes
The gear may be provided with an electro-optical readout either directly or via a code disk. A combination of these indicating devices is also possible.

Suitable indications include magnetically recorded information along the beam and optical markings placed at relatively long intervals, e.g. every 10 cm, on well-dim light indicators such as photodiodes. It can be provided by something like a dimmed light emitting diode which is thus detected. By this means, the indicating device is modernized at sparse intervals and a special indication is obtained that the magnetic marking has been correctly indicated.

The markings are suitably detected in the form of pulses and these are fed to an up-down counter, ie a counter that counts upwards when the deflection device is moved in one direction and downwards when it is moved in the other direction. The indication of the direction in which the device is to be moved is provided in a manner known per se, for example by a special detector displaced with respect to the ordinary detector, for example by a phase shift of 1/4 of a wavelength with respect to said ordinary detector. This is done to measure the marking done.

Distance measurements can also be carried out between the transmitting device (prism device) and the reference point (laser device), for example by ultrasonic acoustic distance measurement or interferometric distance measurement towards the acoustic plane. According to this, the distance can be determined by the existing laser beam or
Alternatively, it can be read by a winding tape or thread, or by a wheel that runs along the light beam and is read.

Shown in FIG. 1 is an operator 15 at the deflection device 12. In one hand he holds a porcelain card 16, which is inserted into the slot 17 (see device 14, which is of the same design as device 12). On the magnetic card there is information about reference data for the car model to be measured. Device 1
There are three instruction windows at 2 and 14;
indicates the reference distance, window 19 indicates the measured distance, and window 20 indicates the deviation between the reference distance and the actually measured distance.

The measurement begins with the operator observing that the beam 21 deflected by the device 12 passes through the marking points on both rear rulers 2 and 3.
The path of motion, ie digit 8, is thus parallel to the longitudinal axis of the car. Using a key on device 12 (not shown), the operator marks this point as the starting point for movement of the device along the path. The distance along which the device moves in order for the deflected beam to strike the rulers 4 and 5 is now shown in the window 18. When the operator moves the device 12 and sees that the light beam impinges on at least one of the rulers 4 and 5,
Press down on another key (not shown) on device 12 to mark it. Windows 19 and 20 show the true distance and the distance between the reference distance and the true distance, respectively.

The device 12 may also be provided with an acoustic indication that will sound when the indication position is within a given tolerance level. This signal can be pulsed or frequency modulated to provide a stepwise indication of deviations from the indicated point. For example, the closer the device is to the pointing point, the higher the pitch of the signal. This feature is particularly suitable when the vehicles to be measured have to be arranged neck-to-neck with certain given dimensions. The operator then moves the device 12 until the sound is heard and finely adjusts the device until the sound is at its softest. If the beam of light does not then pass through the two rulers at the intended point of incidence, align the cars until it does.

After performing the measuring operation on rulers 4 and 5, he presses a key (not shown) to mark that the distances to rulers 6 and 7 are about to be measured, and to Measurements are made in the same manner as for rulers 4 and 5.

In the same way, measurement in the y direction is also performed using deflection device 1.
This is done by moving the 4 along the digit 9. Especially when lining up cars, x for the same measurement point
It is appropriate to mark the and y directions simultaneously.
To accomplish this, the device 12 emits a deflected beam of light toward a ruler and precisely ensures that the beam of light along the digit is along the digit in the same direction as the incident beam of light. The beam of light along the beam is deflected along beam 9 by a stationary deflection device 13 at the intersection of beams 8 and 9, after which the deflected beam from device 12 is deflected by a deflection device 14. It hits one of the rulers 2 and 3 that it is hitting against. In the figure, the light beam from device 14 is shown to impinge on ruler 2.

Both of the two beams emitted by the device 12 can be achieved by placing a semi-transparent mirror in the optical path from the light source 10, so that two fixed beams of roughly the same intensity are formed. will be obtained.
However, if instead the two starting beams were
If the light at the point of impact is modulated at a frequency that makes it appear to the observer as flashing, then
Substantial benefits will be obtained. A suitable frequency may be between 3 and 13Hz. The two modulated light beams from the device 12 must be out of phase with respect to each other such that the point of impact where both beams meet appears to be stationary light.
It would be appropriate that the modulation of the two beams could be in opposite phase. Modulation occurs when a mirror placed in the device 12 in the path of the light beam from the light source 10 is a floating crystal which becomes reflective when the voltage exceeds a certain characteristic value; This can be accomplished simply by making it transparent when added below a value. The floating crystal mirror is excited with a voltage that varies cyclically between these values depending on the modulation frequency. Yet another way of achieving modulation is to place a polarizing means 11 in front of the light source to polarize the light in two mutually perpendicular directions. This deflector may be a Potskel tank excited by an alternating current voltage, and is a rotating disk with a polarizer that alternately blocks and polarizes the light, and the polarizer is arranged in a ring guided into the light beam path. It may be something that has been done. The mirrors placed in the beam path for the incident beam from the light source 10 in the device 12 are polarizing mirrors with suitable dichroic coatings, such mirrors reflecting light polarized in one direction. , allowing light polarized at right angles to it to pass through. Suitably, repolarization of the light from light source 10 occurs at the flash frequency between 3 and 13 Hz.

FIG. 2 shows a second embodiment of the instrument according to the invention, in which only one digit 17 is placed on the side of the car to be checked. A light source 18 and possibly a modulator 19 are permanently located on one end of the bridge 17.

Two deflection devices 20 and 21 are shown on the girder, each of which deflects the light beam emitted from the light source in different directions within one plane, so that the ruler 2 can be moved in two directions. It is arranged so that the light is incident from
The position of the point of incidence in the beam-directed coordinate system is undoubtedly determined from the location along the beam of the two deflection devices 20 and 21 and the angle and distance between the polarized beams from each deflection device. In the figure, the deflected beam is shown to be in the horizontal plane and impinge on a point on the ruler that lies in this plane, but instead of suspending the ruler from the measurement point on the vehicle. In addition, it is also possible to deflect the light beam in the vertical plane by means of a deflection device so that it impinges on different measuring points. Of course, this feature is also applicable to the embodiment according to FIG.

In the embodiment according to FIG. 2, the deflection device includes a detector and a central processing unit 22 indicating the marking on the brush.
Transmitting means are provided for transmitting detection information regarding the distance moved to. Although in the figures this transmission is shown to occur via a cable between the beam and the central unit, it could also occur wirelessly, for example with acoustic transmission or modulated infrared light.

Information about the relevant car model is stored in the central unit 22 prior to the measurement, for example by magnetic card, punched tape, cassette tape recorder, floppy desk, etc., as was the case in the prior art.
can be supplied to the internal memory. The two deflection devices 20 and 21 can both be moved manually by an operator, as indicated in the embodiment according to FIG. Make it fairly small,
It can be easily carried by the operator. For example, it may be the same size as a pocket calculator. In the reading window of the central device for the deflection device, which the operator is then working with, the reference distance, the true distance, and the difference between these values are shown as in the embodiment in FIG. The figures are shown under the same operating conditions. The polarizer 20 is
It should be observed that it may have a deflection of 90°, the movement along the digits of which indicates the distance between the rulers in the x direction (along the longitudinal axis of the car). The deflection device 21 has a deflection other than 90°, and the y-direction distance for each pair of rulers having the same x-coordinate, such as 2, 3 or 4, 5 or 6, 7, is It is given by the distance along the beam of the point of incidence to the device 21 divided by the right angle of the angle between the beam and the deflected beam. If this angle is 45 degrees, the distance moved will be the same as the distance in the y direction.

However, it is also possible to provide the deflection devices 20 and 21 with controllable motors, in which case the operator performs all measuring movements while standing or sitting at the central device as shown in the figure. You can also do it. With the central device it is possible to automatically direct the drive motor to the appropriate settings along the spar according to the input data for the relevant car model. When aligning the cars, the alignment process is continued until the deflected beam of light hits each ruler correctly. When a car is only being measured, the deflection device is automatically moved to a position along the girder that matches the relevant car model and, under key control by the operator, the deflected light beam actually impinges on the point of incidence. point, or the operator can move the deflection device from its starting position by pressing the appropriate key on the keyboard of the central unit 22.

As in the embodiment according to FIG. 1, what is important is the distance between the various positions along the beam. The operator uses a special key or a special code to
Mark that the position of the device constitutes the starting position for the measurement.

The deflection for each deflection device 20 and 21 need not be fixed; instead, the angular position for the deflection can also be changed continuously or stepwise by rotating mirrors contained within the device. It is also adjustable. In the deflection device it is suitable to carry out the deflection with the aid of two reflective surfaces which are set at an angle to each other, analogous to the reflective surfaces in a pentagonal prism. This eliminates the need to transfer the actual deflection device to the girder. Turning one of the mirrors can be read on the micrometer screw, but it is also possible to connect the mirror to a resolver, in which case
Rotation of the mirror can be controlled remotely from a central unit.

In the above, it is assumed that the deflection occurs in one plane, suitably in the horizontal plane, and that the deflected light beam is placed at a predetermined incidence on a ruler suspended above a particular measurement point. I thought I would hit a point. The fact that the deflection device or the central device is equipped with a calculation device means that there is no operational inconvenience in deflecting the light beam in the vertical direction so that it hits the measuring point directly. This is because it can be easily programmed so that the height above the horizontal plane can also be calculated based on each degree. The deflection device can also be provided with rotation means and a vertical angle transducer, for example of the pendulum accelerometer type, for height adjustment and for indicating the vertical angle of the deflected beam. When two mirrors set similar to the reflecting surfaces of a pentagonal prism are used for polarization, the height adjustment and height indicating means for these should be adjusted so that the bisector between the reflecting surfaces is on the optical axis of the incident light beam. It is appropriate to have a suitable inclination around the turning point of . The calculation device performs a geometrical calculation of the height angle of the bisector and also calculates the deviation of the deflection angle in the horizontal plane due to the height adjustment of the luminous flux. Another variant of the vertical adjustment of the luminous flux is, for example, the zero position - by means of a servo-controlled level or angle transducer, the bisector between the reflecting surfaces is kept horizontal, and then deflected into the horizontal plane by a mirror. The objective is to ensure that the emitted light beam is vertically deflected by a rotatable deflection means, such as a mirror, placed in the beam path.

Diagrammatically shown in FIG. 3 is a block diagram embodiment of the electrical connections for the device according to the invention. A light source 30 is permanently placed at one end of the girder. An important characteristic of the light source is that it must be capable of emitting a narrowly collimated beam of light such that from the operator's point of view, the beam striking one of the rulers is clearly discernible. That's true. A He-Ne type laser satisfies this requirement. A device could possibly be placed in front of the light source to achieve modulation of the light. Here, this is shown as a rotating disk 31 driven by a drive motor 32, rings 3 with polaroids placed alternately with polaroids intersecting each other.
It is provided with the number 3.

Two deflection devices are provided on the beam. Both have mirrors arranged similar to the reflective surfaces of a pentagonal prism. Device 34 should achieve vertical deflection of the beam from laser 30 and mirror 3
The angle between 6 and 37 is then 45°. Device 3
5 should achieve an obtuse angle deflection of the beam from the laser 30, and if this angle is 45°, the mirror 38,
The angle θ between 39 and 39 is 67.5°. Placing the mirrors in the device analogous to the reflective surfaces of pentagonal prisms provides insensitivity to rotation of the device on the girder.

If the mirror 37 is a polarizing mirror, for example coated with a dichroic coating, that mirror will reflect light polarized in one direction and allow light polarized in the other direction to pass through, so it will not be radiated. is reflected during half of the rotation of the rotating disk 31, and is passed during the other half. As mentioned above, instead of devices 31-33 and polarized mirror 37, a floating crystal mirror may be used, in which case a pulsed alternating current voltage is applied to its electrodes.

The polarizing device 34 has an indicator 40, and the polarizing device 34 has an indicator 40.
5 has an indicator 41 adapted to read markings 42 provided on the digits.
The indicators 40 and 41 are each connected to a data processing device 43.
includes an up/down counter connected to the up/down counter, which continues to set the counter at special points in time.
A memory 44 is connected to device 43. Before the measurement, information about the object to be measured is read into the memory via data inputs. Data regarding the actual object is presented on visual display device 45 and acoustic indications 46 may be arranged as previously described. Use the keyboard 47 to select which function is active at the time.
The operator states what needs to be presented. Elements 43-48 can, of course, be arranged separately in each deflection device, common to both devices 34 and 35, instead of in a central device, as described in connection with FIG.

As described with reference to FIG. 2, devices 34 and 35
If the and is to be controlled from a central device, the data is fed to a control device 48, which in turn controls the respective drive motors 49 and 50 in the deflection devices 34 and 35 at the start of the measurement. The robot is driven to run along the bar to the intended location in accordance with the data supplied to the hit memory 44.
The control device 48 also takes care of setting the angle between the mirrors for the purpose of modifying the deflection angle by controlling the reset devices 51 and 52, respectively, in each individual device 34 and 35. Horizontal indicating means 53 and 5
4 are each placed relative to the bisector between the mirrors in the deflection device to sense deviations from the horizontal position. The apparatus includes a conventional adjustable scanning device (not shown) which automatically rotates the devices 34 and 35 so that the means 53 and 54, respectively, are always in a horizontal position and the possible height alignment of the deflected beam is limited. ), or else the vertical setting is achieved by rotating the means 53 and 54, respectively, to a particular inclination calculated in the data processing device.
The means are, for example, Swedish Patent No. 7806294
A pendulum accelerometer of the type indicated in number -0 may be used.

The data processing device 43 appropriately calculates the position to the check point within the object fixed coordinate system. This is a system that is determined for the digits at the beginning of the measurement through measurements towards a reference point. When a central processing unit is used, once a series of measurements has been completed, this includes special data for the object being measured, such as diagonal measurements, and/or measuring points within predefined tolerances. is on a particular curve, etc., and based on these criteria indicates in the reading window whether the measurement object should be accepted or not.

Various modifications are possible within the scope of the invention; for example, the devices 12, 14, 20, 21 may not necessarily deflect the light beam projected along the girder; with its own light source,
It may also be possible to project at different angular positions with respect to the girder.

[Brief explanation of drawings]

FIG. 1 shows a first embodiment of the device according to the invention. FIG. 2 shows a second embodiment according to the invention. FIG. 3 shows an embodiment for measuring movement along a beam.

Claims (1)

[Scope of Claims] 1. A device for measuring the dimensions and/or checking the accuracy of dimensions of a large object 1, such as a car body or the like, said object being a bolt head,
comprising a checking point such as a suspended measuring rod or the like; comprising at least one measuring girder erected near said object; emitting a narrow beam of light at an angle to said girder; and at least one movable transmitting device 12, 14; 20, 21, which is movable along the measuring digit, is provided on the measuring digit; at least selected movements of the beam emitting unit on the measuring digit are provided. comprising a computing device 43, 44 having a memory for storing; comprising a device for entering into said memory 44 reference measurement data for said reference model of said object; the measurement operation being a reference measurement operation; In the dimensional accuracy checking device comprising a device 47 for inputting information regarding the measurement, the calculation device calculates the accuracy of the measurement from one or several measurement operations on at least one check point on the object. the position of the remaining check point of the reference model of the object with respect to the girder and the position of the beam emitting unit of the possible angular settings of the beam emitting unit with respect to the measuring girder for illuminating this remaining check point; said beam emitting unit for automatically reading the distance between said beam emitting unit and a reference point on said digit provided by said reference measurement input device 47; A reading device 40, 41 is provided in each of the
each time a beam emitting unit with a determined angle setting is placed at or near a location where the beam will illuminate one of the check points on the reference model of the object; A dimensional accuracy checking device characterized in that it is provided with indicating devices 45, 46 for giving easily perceptible signals such as target signals. 2. A device for storing the tolerance deviation for the position of the check point of the reference model is provided in the memory of the computing device, and the indicating device 45, 46 is configured to store the tolerance deviation with respect to the position of the check point of the reference model; 2. The dimensional accuracy check device according to claim 1, wherein the dimensional accuracy check device is adapted to give an instruction as soon as the light beam emitting unit is set within the range. 3 The luminous flux emitting unit or the device 1
2, 14; 20, 21 each emit one light beam in one common plane, the dimensions of the reference property of the object are stated in a two-dimensional coordinate system in this plane, and the calculation device 43 Claims 1 or 2, wherein data of the two-dimensional coordinate system for the object being measured is compared with data for a reference model to indicate deviations from associated set point values. Dimensional accuracy check device described in . 4 The luminous flux emitting unit 12, 14; 20, 2
1 is variable in two dimensions with respect to an order-of-magnitude motion path;
calculates and compares the data measured and stored in three dimensions and provides a visual indication and/or acoustic signal whether the measurement check point is within predetermined tolerance limits. A dimensional accuracy check device according to any one of claims 1 to 3, wherein the dimensional accuracy check device is adapted to control the indicating device to ensure that the dimensional accuracy is correct. 5 Each of said beam emitting units 12, 14 has its own computing device and visual display device (first
A dimensional accuracy check device according to any one of claims 1 to 4, wherein the dimensional accuracy check device is provided with: 6. Dimensions according to any one of claims 1 to 5, in which a plurality of said beam emitting units 20, 21 cooperate with one common calculation device 22 (FIG. 2). Accuracy check device. 7 After completing a series of measurements for several measuring points, a special calculation is performed on the basis of the calculated positions for the check points to calculate diagonal measurements or to draw curved lines with the plotted check points. The computing device is equipped with a device configured to perform calculations such as the shape of the object, and based on this special calculation, the computing device visually or acoustically indicates whether or not the object is acceptable. A dimensional accuracy check device according to any one of claims 1 to 6. 8. The dimensional accuracy check device according to any one of claims 1 to 7, wherein the beam emitting unit comprises a light source 10; 18 that emits a beam parallel to the digit, and a beam deflector. .