JPH01152304A - Method and apparatus for measuring object between transport sections - Google Patents

Abstract

PURPOSE: To measure a target on a carrying path accurately by forming a raised part and a slit part on the carrying path and measuring the dimension of the target that passes this part using an optical means. CONSTITUTION: A target 10 moves in a carrying path 3 of a vibration conveyor and reaches a measurement part. A CCD 14 and a light source 8 that are fixed to the carrying path 3 are provided at the measurement part and a slit 9 and a raised part 15 are formed at the carrying path 3. The raised part 15 lifts the target 10 that is carried to a measurement part and facilitates the measurement by the light source 8 and the CCD 14. Also, the slit 9 completely detects a target that slides at the measurement part, passes it, and cannot be lifted. A measurement part consisting of the CCD 14 and the light source 8 vibrates along with the carrying path 3 so that the above slit 9 can be retained to be small, thus detecting even a small target effectively. The target 10 with a dimension other than a reference value is eliminated from the carrying path 3 due to an air pressure pulser 13 as a result of the above measurement.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method according to the generic concept of claim 1 and an apparatus according to the generic concept of claim 6.

BACKGROUND OF THE INVENTION Various devices are known for conveying objects, in particular for feeding objects to machine tools, such as, in particular, so-called vibrating conveyors. For this purpose reference may be made, for example, to West German patent application P3331050.5-14. Generally BETRIEBS-TECHN for vibration conveyor technology
Beta S on pages 61-64 of IK 19B2 Vol1.10.

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"icht" is also referred to.

Such conveyors often not only supply objects to subsequent processing equipment, but also carry out practical tasks such as sorting, specific orientation of objects, rejection of incorrectly processed objects, etc. is also achieved. For this purpose, it is known, for example, to scan the object with a light projector/receiver and to remove objects that are not recognized as suitable from the conveyor by means of a balsa arranged in the light projector/receiver plane (West German Utility Model Registration No. 8534584). issue). However, in this known device it is necessary to incorporate a non-vibrating intermediate member in the transport path of the vibrating conveyor, since the object has to slide past the measuring point and not vibrate through the microconveyor. Because you shouldn't. Moreover, it is not possible to recognize whether or not the shape of the surface on which the object passing through the measurement location satisfies the conveyance path is satisfied by the known measurement method.

In view of this state of the art, the present invention provides a method and a device known in the art which enable an acceptable recognition of the object to be excluded with the simplest possible construction of the measuring point with respect to the conveying path. It is an object of the present invention to create a measuring method and a device for the measurement that can be carried out with as comprehensive a technical detectability as possible of the object (means for solving the problem). The problem is solved by the method and device described in claim 1 and claim 6.

In the method according to the invention, when vibrations are used, it is not necessary to provide non-vibrating parts of the transport path in the area of the measurement point. Also at the measurement location, vibrations are applied to send the object by the microconveyor, and the vibrations send the object forward by the microconveyor and do not cause lifting of the object from the conveyance path. Moreover, the lifting of objects necessary to practice the invention can be accomplished in other ways.

According to the invention, the present invention is implemented with objects that are lifted from the conveyor path in the area of the measuring point.According to the invention, without exception, this invention applies only to devices in which lifting of the object from the conveyor path is carried out in the area of the measuring point. It does not mean that it is assumed that Depending on the configuration of the device, in practice even parts of the object can be delivered to the measuring location without lifting them, which will be explained in more detail below, if a slit or a transparent section at the measuring location is provided in the transport path. There is. - the measurement technique is carried out over the height of the object in a raised position or in a configuration with a slit in the conveyor path, so that the underside of the object is also detected, e.g. the thickness of the object. . At the same time, breakage of objects can also be detected. A comparison with the stored measurement values establishes whether the object detected in the measurement technique is "good" or should be rejected.

In the configuration of the method, a series of measurements are carried out successively during the forward movement of the object in the measuring device, so that the length of the object is also detected by the measuring device, which retains the measurements over the height of the object. It is proposed that However, especially with vibrating conveyors, the object is passed through the measuring point in a manner exactly parallel to the measuring point or in a specified manner.
For length measurements, values are easily detected that do not correspond to the predetermined target value if the object is passed through the measuring point oriented obliquely and only the projection of its length is measured as length. . The invention therefore proposes that the measured dimensions of objects having different ranges are each related to a predetermined dimension and that the relative values thus obtained are compared with the stored relative values. be done. If the object has a total length of 6 mm, the first part is 3IllI11, the second part is 3 mm, and the thickness is 4 mm, the first length range is 50% of the total length, and the second length is 50% of the total length. Measurement technology detects that the ranges are similar. Objects whose measured part dimensions are not each 50% of the total length are excluded in this case. The formation of relative values is carried out in such a way that the measured part dimensions are related to the total measured dimensions.

However, predetermined and stored dimensions can also be correlated to form relative values. It is essential that the measured values are not directly compared. Thickness can also be used directly.

If preference is given to carrying out measurements at high frequencies, then frequencies of 1 to 20 MHz can be provided. A very dense matrix of measured values can thereby be obtained.

Depending on the result of the measured value comparison, objects are removed from the transport path. This can be done, for example, by the already mentioned pneumatic pulsers, free fall, plungers, etc. Exclusion can be performed by magnets, for example electromagnets.

The invention provides a device in which the conveying path is part of a vibrating conveyor path in the area of measuring points, the measuring points are realized by electro-optical elements and a comparison between the stored and measured values can be carried out. is proposed. In this case, the invention is of course not limited to the fact that the conveying path is part of a vibrating conveyor path in the area of the measurement location; other methods of lifting can also be carried out pneumatically. Advantageously, the measuring point itself is formed by a so-called CCD cell. CCD cells are known, for example, from ceramic technology. In particular, a plurality of such rows can also be arranged in the form of a so-called array. This type of optical sensor row has a size of approximately 3 mm (256 electro-optical elements (light spots)) to 27 mm (2,048 light spots).

Another advantageous embodiment is that a CCD cell of this type is arranged two-dimensionally, i.e. transversely to the transport path for the detection of the height of the transported object and the width of the transported object. will be placed.

Since the conveying path in the area of the measuring point on a vibratory conveyor is a regular part of the conveying path of such a vibratory conveyor, the relative atrandom movement of the objects on the vibratory conveyor is carried out according to the width of the conveying path, and 2 The two objects are positioned one above the other or partially overlap each other and pass through the measurement location.

The objects can be arranged closely one behind the other so that in electro-optical systems false signals can occur with respect to length. The invention proposes that it is possible to carry out the removal of objects conveyed in the direction of conveyance on the conveyor path in front of the measuring point. Various measures are suitable for this purpose. For example, braking of the object can be carried out pneumatically. Mechanical barriers are also possible. On the other hand, it is possible that the system is also an object itself located side by side or directly one after the other, since it has no tolerance dimensions and this is detected as an object that is excluded from the system. It is. Depending on the case of use, this leads to the desired delay so that it is advantageous to carry out the separation described.

Particularly within the scope of the invention, the conveying path has, in front of the measuring point, a ridge or the like which rises above the level of the conveying path and into the area of the measuring point. On the rising side of the protrusion, the object that has exceeded the top of the protrusion is accelerated by the descending side, and is stopped by the conveying section while passing through the measurement location.

In order to safely carry out continuous detection of the height of the passing object, it is advantageous if the conveying path is interrupted in the area of the measuring point. For this purpose, the invention proposes that the conveying path is designed transparently in the area of the measurement location. In particular, the measuring section can be provided with a slit or made transparent. If the slits or transparent points are located in the area of the measuring point at the lateral boundaries of the conveying path, but also within the conveying path, even objects that cannot be lifted up and slide past the measuring point can be completely detected.

It is important that the measuring device is fixed to the vibrating part of the transport device. The measuring device vibrates together with the transport device. No relative movement occurs between the measuring device and the conveyor. As a result, the slit or transparent arrangement of the conveying path at the measuring location is advantageously kept small, so that even very small objects can be detected in an enhanced manner by the described device.

After all, an element that acts on the object is also provided in the device, so that the element passes through the measurement location in order to remove the object, ie to remove it from the transport path or to align it in the desired manner. For removal a pneumatic pulser is used. Moreover, such devices are as described above.

(Example) FIG. 1 shows a vibrating helical conveyor 1, which has a measuring device 2, which allows objects to be measured without the need for special contact parts in the conveying path 3. can be detected technically.

In its basic structure, the vibratory helical conveyor according to FIG.

The vibrating linear conveyor according to FIG. 2 is comparable in principle to this.

The device according to the invention, detailed in FIG.
D-consists of a battery 14 (disposed in the example in an element designated by 14), which is illuminated by a light source 8 arranged opposite the conveying path 3 as it passes through the measuring point; In order to ensure that possible measurements of the object 10 are possible, an interruption is made within the measuring point in the form of a slit 9.

In the conveyor device in front of the measuring point, the conveyor lllll3
1, on which the objects 10 are conveyed by a vibratory movement, the objects being located close to each other in the device. As soon as the object 10 passes the apex 12 of the elevation 11, it undergoes an additional acceleration and passes individually through the measuring point or CCD cell 14.

For example, a pneumatic ballast 13 can be provided in the conveying device behind the measuring point for displacement.

In the embodiment according to FIG. 3, for example, the object 10', which has already passed the measuring point, is not aligned, ie there is a pin-shaped projection of small diameter in front, but the projection should be at the rear in the desired arrangement. , and the object should be moved on the transport path 3 with a turn of approximately 180'. In the exemplary embodiment, this object 10" is therefore removed from the conveyor path 3 by the balsa 13. The same applies if the object 10" is passed through the measuring point by the object 10'' which is now in front of the measuring point. It will be done.

As shown in particular in FIGS. 1 and 2, the measuring section 2 is fixed to the vibrating part of the vibrating helical conveyor 1. As shown in FIGS. Measurement section 2 carries out vibrations of the vibrating helical conveyor 1. This results in an optimally small slit 9, which correspondingly makes it possible to transport very small objects and to detect them metrologically with such a device.

The rear wall 16 of the vibrating helical conveyor is also not shown in FIG. 3 for better visibility, but this is shown in FIG. 4. Measuring point 1 is shown in Figure 4 only for clarity of illustration.
4 and pulsar 13 are shown at a large distance from each other. In practice, these elements are arranged in close proximity in order to be able to carry out any necessary exclusion immediately after the measurement-technical detection.

FIG. 4 shows an enlarged view of the object 10 passing through the measurement point 14. - Figure 10″ shown in dot-dashed line
The object 10, which is shown in a lifted state, follows a zigzag movement path 15 on the conveyor path 3.

A vibrating conveyor lifts the object lO to the position indicated at 10° and simultaneously sends it forward. FIG. 4 shows the movement of the object 10 only schematically. In reality, a large number of movement possibilities arise. The object swings and passes through the measurement location at an angle. Measuring detection takes place at the position where the relevant part of the object just passes through the measuring point 10. A measurement record (idealized diagram) corresponding to FIG. 5 is thus obtained if the detected values are plotted on a recording paper running at a constant speed.

FIG. 5a shows an object 10 to be measured, a first part of which has a length and a diameter D1, and a second part of which has a length L2 and a diameter D2. In the recording according to FIG. 5b, a measurement result is shown in which the object passes through the measurement location very slowly.

A corresponding number of measurements are carried out. Lengths 1 and L2 are therefore larger than the actual object to be measured. For this reason, relative values are formed for the lengths, either by predetermined constant values or with respect to the measured total length, and only the relative lengths of the detected parts are compared with each other as described above.

The thicknesses (diameters) 01 and D2 almost correspond to the actual values in this example. By passing the individual sections through the measuring points at different heights, a height displacement in the measurement record as well as a displacement with respect to the length L2 of the ascending curve is obtained. Fifth
In the measurement record according to diagram c, the object passes through the measurement location relatively quickly. Correspondingly, a smaller length is obtained on the measurement record than actually exists. The described relative movements again provide assistance here. The features of the invention disclosed in the specification, drawings and claims are important for the invention, both individually and in any combination for implementing the invention.

[Brief explanation of the drawing]

Fig. 1 is a principle diagram of a vibrating spiral conveyor equipped with a measuring device according to the present invention, and Fig. 2 is a principle diagram of a vibrating spiral conveyor.
FIG. 3 shows an enlarged front view of the transport path of a vibrating linear conveyor equipped with a measuring device according to the invention, a single view of an object (5a) and a schematic representation of a possible measurement record (5b, 5C). Symbol 3 in the figure... Conveyance path 7... CCD-battery 10... Target object

Claims (1)

[Claims] 1. A method for detecting the position, shape, etc. of an object (10) moved by a conveyance path, in which the object is excluded from the conveyance path (3) within the range of the measurement point. In a product, the object on the conveyor path is conveyed along the longitudinal direction at the measuring point, and the object is lifted from the conveyor path in parallel with the forward movement of the object on the conveyor path in the range of the measuring point. A method as described above, characterized in that a metrological detection of the dimensions of the object is carried out in the lifted position, and the measured values detected in the lifted position are compared with setpoint values. 2. The method according to claim 1, wherein lifting of the object is performed by vibration of the conveying path. 3. Each part of the object is measured, and the measured dimensions of the object having different extents are related to predetermined dimensions and the relative values so obtained are compared. The method described in 2. 4. The method according to any one of claims 1 to 3, wherein the measurements are carried out at a frequency of approximately 1 to 20 MHz. 5. The method as claimed in claim 1, wherein an action on the object can be carried out depending on the measured value comparison. 6. In a device for detecting the length, shape, etc. of an object on a conveyance path for carrying out the method according to claim 1, the conveyance path (3) is a vibration conveyance path within the range of the measurement point. Device, characterized in that the measuring point is realized by an electro-optical element (7) and that a comparison between the stored measured value and the measured value can be carried out. 7. A so-called CCD battery (7) whose measurement point can be illuminated by a light source (8) arranged opposite the transport path (3)
7. The device of claim 6, formed by: 8. Device according to claim 6 or 7, characterized in that a plurality of CCd-cells (7) are provided. 9. Device according to any one of claims 6 to 8, characterized in that one or more CCD-cells (7) are arranged in two dimensions. 10. Device according to claim 6, characterized in that it is possible to remove objects (10) conveyed onto the conveyor path (9) in the conveyor direction of the measuring point. 11. Any one of claims 6 to 10, wherein the conveyance path (3) has, in front of the measurement point, a raised part (11) or the like that rises above the level of the conveyance path (3) to the range of the measurement point. The device described in (1) above. 12. Device according to claim 6, characterized in that the conveying path (3) is constructed in a light-transmissive manner in the area of the measuring point. 13. Device according to one of claims 6 to 12, characterized in that the conveying path (3) is provided with a slit in the area of the measuring point. 14. Device according to claim 6, characterized in that the conveying path (3) is transparent in the area of the measuring point. 15. Device according to one of claims 6 to 14, characterized in that an influence can be exerted on the object (10) depending on the measurement result. 16. The device according to any one of claims 6 to 15, wherein the device is pneumatically acted upon the object (10). 17. Device according to any one of claims 6 to 16, which is operable on the object (10) by means of a magnet. 18. Device according to any one of claims 6 to 17, characterized in that the measuring device (2) is fixed to the vibrating part of the device (1).