EP0153575B1 - Method and device for checking and separating bricks - Google Patents

Description

The invention relates to a method and a device for testing and sorting bricks, which are individually fed on a first conveyor belt to a test device provided with stylus pins and connected to a measuring device, each brick being scanned for flatness by the test device. It is common, for example, to burn baked beaver tail bricks with an eye for flatness, i.e. check for deflection or twisting and, if necessary, cut out bricks that deviate too much. Given today's quality requirements of customers and the large production quantities, such sorting by hand is only possible with considerable personnel expenditure, and the sortability over a longer period of time is also physically demanding.

As the state of the art, from which the present invention is based, a device for checking the measurement and shape accuracy, in particular plate-shaped objects, is known (DE-OS 24 34 603). Two parallel conveyor belts are provided on which these objects are transported. The object to be tested is pressed by a support plate against a stationary measuring plate which has styli. In this way, the measurement is carried out, after which the object, for example a ceramic plate, is given a marking by a marking element, which indicates whether this object meets the requirements or is to be evaluated as waste.

The disadvantage of this known construction is the high structural complexity and the method step that only the objects to be checked are marked, but not automatically eliminated, so that ultimately this operation has to be carried out by an operator.

The state of the art also includes an aggregate for automatically sorting fired bricks (DE-OS 29 07 700). This known device has a hanging trolley carrying a test device with a gripping device for bricks, the bricks being able to be placed on different conveyor belts depending on their quality. This known construction is also complex due to the greater number of conveyor belts, the test device also being designed as a photocell and light source and accordingly being susceptible to failure in rough operation.

Furthermore, a method for sorting out less solid and broken ceramic moldings from a conveying stream running continuously on a conveyor belt to a stacking machine is known (DE-AS 1 109 076). Here, the moldings are individually subjected to a pressure-bending load during the conveyance on a preferably two-part conveyor track, the moldings which cannot withstand this load and are not broken further on the conveyor belt, but fall out of the conveying stream. This known method is therefore only used to check the strength of the ceramic moldings, but not to determine the flatness, i.e. this procedure cannot be used for high quality requirements.

In addition, a removal device for stone and molding presses is known from the prior art, mechanically actuated arms being used which grip the moldings laterally by means of pneumatic overpressure by means of pressing members that bulge toward the molding (DE-PS 1-012-241). In this case, the pressure members are designed as a membrane, with each membrane having special elastic supports which rest on the moldings. This known device is therefore not used for quality control of ceramic moldings.

In contrast, the present invention has for its object to provide a method and an apparatus of the type mentioned, in which a quality control of bricks is possible in a simple, cost-saving and effective manner.

According to the invention, this object is achieved in a method in that each tile is checked by the measuring device during the movement of a swiveling device carrying the test device from the first conveyor belt to a second conveyor belt and either thrown off as waste or deposited on the second conveyor belt, and wherein the feeler pins of the test device consisting of the holding part and the test part control the holding action of the holding part via the measuring device.

This results in the advantage that the heavy manual work when testing bricks with regard to their flatness is eliminated, the testing device taking on both the transport and the testing process and deciding whether a brick can be discarded or used as a quality product. The entire workflow takes place automatically, without the need for an operator to intervene.

The device for carrying out the method is based on a first conveyor belt and a test device provided with stylus pins and a test device connected to a measuring device. According to the invention, a swivel device and a second conveyor belt are arranged downstream of the first conveyor belt, the swivel device designed as a double rocker carrying the measuring and testing device with the feeler pins and the feeler pins of the testing device consisting of holding part and test part controlling the holding action of the holding part via the measuring device, whereby a waste device is located below the double rocker. This is a simply constructed device which ensures that the test procedure takes place during the swiveling movement between the two conveyor belts.

According to a further feature of the invention, each individual brick can be held mechanically, hydraulically or pneumatically by the holding part. In a constructive development, it is possible that, for example, the holding part is designed as a pneumatic suction head, with a suction plate and fixed points. Here, the suction plate can be arranged axially movable on a membrane, outside the suction plate three contact pins are provided as fixed points and the test part has at least two axially movable, offset to the fixed points probe pins.

Each stylus can be connected to a translation device, this translation device being designed, for example, as a three-armed, spring-loaded lever, one lever arm of which controls the optically acting measuring device. In order to be able to detect tolerance zones set for the respective type of brick, the lever arm interacting with the measuring device can be adjustable. The measuring device can be designed electronically, mechanically, electrotechnically, hydraulically or pneumatically.

• Fig. 1 eine schematische Seitenansicht der erfindungsgemässen Vorrichtung;
• Fig. 2 eine Draufsicht auf einen Saugkopf nach der Erfindung;
• Fig. 3 einen Schnitt nach der Linie 111-111 in Fig. 2;
• Fig. 4 eine schematische Seitenansicht eines Teils der Prüfvorrichtung.

The invention is described below with reference to an embodiment shown in the drawing. The drawing shows:

• 1 shows a schematic side view of the device according to the invention;
• Fig. 2 is a plan view of a suction head according to the invention;
• 3 shows a section along the line 111-111 in Fig. 2.
• Fig. 4 is a schematic side view of part of the test device.

In Fig. 1, a device for checking and sorting bricks is shown schematically. Here, two conveyor belts 1 and 2 are used, a conveyor device 4 being arranged between these two conveyor belts 1 and 2. Between the conveyor belts 1 and 2 there is a test device 3 which is arranged on a swivel device 6. In the present case, this swiveling device 6 is designed as a double swing arm with the two swinging arms 7 and 8 and the coupling part 9. Between the coupling part 9 and the swing arms 7 and 8 there are joints 31 and 32; the wings 7 and 8 are firmly connected to the ground via joints 33 and 34.

The test device 3 has contact pins 14 and feeler pins 16, which will be described in more detail later. As can be seen from FIG. 1, a brick 5, for example a beaver tail brick, is moved on the conveyor belt 1 in the direction of the arrow and is detected by the test device 3 when the swivel device 6 is in the left position . Now, as a result of the movement of the double rockers 7 and 8, the testing device 3 swivels to the right over the central point to the conveyor belt 2. During this movement, the tile in question is checked for flatness and twisting. If this brick does not meet the quality requirements of the test devices 3, this brick 5 'is thrown off in the central position of the swivel device 6 and passes through guide walls 30 to a removal device 4, for example a conveyor belt, which transports the waste brick away.

If the relevant brick 5 "corresponds to the quality requirements, it is placed in the right position of the swivel device 6 on the conveyor belt 2, separated from the testing device 3 and, for example, transported to the packaging.

The bricks 5 are thus transported on a belt 1 with the visible surface lying upwards. A test head 3 on the coupling part 9 grips the brick, lifts it and moves it in a circular direction. The flatness of the tile is measured during this movement. If this flatness lies within predefined tolerances, the brick 5 "is transported to the end point of the circular arc and placed on a conveyor belt 2. If the tolerances are too large, ie if the brick 5 'is twisted or bent, it will be approximately in the middle of the circular arc from of the test device 3 is released and falls onto the removal device 4.

The checking of the bricks 5 for flatness takes place in the following way: According to FIG. 2, the testing device consists of three fixed points 14, which are arranged, for example, in a triangle. Two movable styli 16, which are located, for example, in the middle of the beaver tail tile and at the corner of a rectangle, check the flatness. The slight axial movement of the stylus 16 is translated in any ratio and fed to a measuring device.

3 shows the construction of the test device 3. This test device 3 essentially consists of a holding part 10 and a test part 11. According to FIG. 3, the holding part 10 has a suction plate 12 and a suction head 13. The suction head 13 is fastened to a housing 35 of the holding part 10 via a membrane 15. The stylus pins 16 and the contact pins 14 are also arranged on the housing.

• Der am Prüfkopf 2 angebrachte Saugkopf 13, der in dem Moment abhebt, in dem der Ziegel 5 angesaugt wird, drückt diesen mit der Sichtfläche gegen die drei Festpunkte 14, d.h. die Anlagestifte. Diese Anlagestifte, d.h. die Festpunkte 14, sind nach Fig. 2 beispielsweise im Dreieck angeordnet. Zwei bewegliche Taststifte 16, welche beim Biberschwanzziegel z.B. in der Mitte sowie an der Ecke eines Rechtecks angeordnet sind, prüfen die Ebenflächigkeit. Dabei wird die geringe axiale Bewegung der Taststifte 16 in einem beliebigen Verhältnis übersetzt und auf eine Messvorrichtung übertragen.

The holding and testing of the brick 5 is carried out as follows:

• The suction head 13 attached to the test head 2, which lifts off the moment the brick 5 is sucked in, presses it with the visible surface against the three fixed points 14, ie the contact pins. These contact pins, ie the fixed points 14, are arranged according to FIG. 2, for example in a triangle. Two movable styli 16, which are arranged in the beaver tail tile, for example in the middle and at the corner of a rectangle, check the flatness. The slight axial movement of the stylus 16 is translated in any ratio and transferred to a measuring device.

The suction head 13 installed in the testing device 3 functions in such a way that a suction lath 12 is mounted on a membrane 15 so as to be axially movable. If the suction plate 12 is now placed on the brick 5 and air is sucked out through the suction head 13, the brick 5 is first pressed against the suction head 13 and then raised by the resulting negative pressure on the membrane 15 and against the fixed points 14, i.e. the contact pins. After this process, the styli 16 take effect and measure the flatness of the brick.

A single stylus is shown in FIG. This is stored in the housing 15 of the test device 3. Above the stylus 16 there is a three-armed lever 18 with the arms 20, 21 and 22, which is rotatably mounted in a pivot point 26. The arm 20 is spring-loaded, the arm 21 is connected to the upper part of the stylus 16, the arm 22 works with a light source 25.

If the measuring device 17, which is designed as a three-armed lever, is in the region of the light beam 25 if the brick to be measured is of good quality, ie If the lever arm 22 projects into this area of the light beam 25, the relevant, high-quality brick is transported over the circular arc to the removal device 2 and is deposited there as a brick 5 ″.

However, if, as shown in Fig. 4, a poor quality brick 5 "is present, the stylus 16 lowers down to its flange 40, as a result of which the three-armed lever 18 moves under the action of the spring 19 in the clockwise direction and thus out of the range The light beam 25 now controls a device (not shown in detail), as a result of which the holding part 10 of the test device 3 no longer has a suction pressure and the waste brick 5 'in question thus passes through the guide walls 30 onto the waste device 4 and is transported away.

In order to be able to set the tolerance range T, a further lever 23 can be attached to the lever arm 22 of the three-armed lever 18 via a pivot point 24. The two levers 22 and 23 thus give a tolerance zone T in the upper region; Within this tolerance zone, the flatness of the tile to be tested meets the quality requirements. In this case, it is possible to pivot lever 23 closer or farther about pivot point 24 in the event of changed quality requirements and thus to increase or decrease the tolerance zone T.

It is also possible that, in reverse of the construction, the test device 3 throws off a waste brick 5 'when the light beam 25 is interrupted.

The measuring device 17 can be designed mechanically, electrically, electronically, hydraulically or pneumatically and is in any case able to give the holding part 10 the control command to transport it to the conveyor belt 2 with a good quality brick 5 ″ or with waste brick 5 'Throw this on the discharge device 4.

The device according to the invention makes it possible to test bricks of all kinds for their quality in a simple manner without heavy manual work.

Claims (9)

1. A method of checking and sorting out tiles which are fed on a first conveyor belt (1) individually to a checking device (3) which is provided with feeler pins (16) and which is connected to a measuring device (17), in which respect each tile (5, 5', 5") is examined by the checking device (3) for surface flatness, characterised in that each tile (5, 5', 5") is checked by the measuring device (17) by way of the feeler pins (16) during the movement of a swivelling mechanism (6), carrying the checking device (3), from the first conveyor belt (1) to a second conveyor belt (2) and is either discarded as waste (5') or is deposited on the second conveyor belt (2) and in that the feeler pins (16) of the checking device (3) which consists of holding parts (1) and checking parts (11) control by way of the measuring device (17) the holding action of the holding part (10).

2. A device for carrying out the method according to claim 1, with a first conveyor belt (2) and checking device (3) which is provided with feeler pins (16) and which is connected to a measuring device (17), characterised in that a swivelling mechanism (6) and a second conveyor belt (2) are arranged subsequent to the first conveyor belt (1), in that the swivelling mechanism (6) designed as a double rocker arm carries the measuring and checking device (3, 17) with the feeler pins (16), in that the feeler pins of the checking mechanism (3) consisting of holding parts (10) and checking parts (11) control by way of the measuring device (17) the holding action of the holding part (1) and in that a waste conveying device (4) is arranged underneath the double rocker arm.

3. A device according to claim 2, characterised in that the checking device (3) with the holding part (10) is arranged on the coupling part (9) of the double rocker arm.

4. A device according to claim 3, characterised in that each individual tile (5, 5', 5") is held mechanically, hydraulically or pneumatically by the holding part (10).

5. A device according to claim 4, characterised in that the holding part (10) is designed as a pneumatic suction head (13) with suction plate (12) and fixed points (14).

6. A device according to claim 5, characterised in that the suction plate (12) is arranged so as to be axially movable on a diaphragm (15), in which respect three abutment pins are provided as fixed points (14) outside least two axially movable feeler pins (16) which are arranged offset with regard to the fixed points (14).

7. A device according to claim 6, characterised in that each feeler pin (16) is connected to a transmission mechanism.

8. A device according to claim 7, characterised in that the transmission mechanism is a three-armed spring-impinged lever (18), the one lever arm (22) of which controls the optically acting measuring device.

9. A device according to claim 8, characterised in that the lever arm (22) co-operating with the measuring device is adjustable.

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