Patent ID: 12253441

DETAILED DESCRIPTION

An implementation of the inspection system according to the invention will now be described using an example.FIG.1shows an isometric view of the whole inspection system. This figure will be used repeatedly to describe the operation of the system.

The inspection system1is used to inspect a plurality of screws as inspection objects in the sense of the present application. The screws are delivered as loose material and fed into the inspection via a feed device2. In addition to the feed device2, the inspection system1comprises a conveying device3, an ejecting device (not shown in the figure) and two inspection units4,5.

In the shown embodiment, the feed device2is driven by gravity; i.e., the individual screws slide over a feed bevel6in the direction of the conveying device3due to their mass. This is shown in the side view ofFIG.5. The screws are already lined up in the feed device2, but are still in direct contact with one another so that they are not yet separated. The screws hang on the feed bevel6with their heads or the surface on the underside of the screw heads. The conveying device3always picks up exactly one screw from the feed device2and conveys it along a conveying path with a spacing to the preceding screw and to the following screw. The conveying path is described in detail below.

In the sense of the present application, the path along which the screws travel between the feed position7, at which the feed device2is disposed, and the ejecting device is referred to as the conveying path. The path along which the receptacles for the individual screws move in the conveying device3as a whole is referred to as the movement path.

The conveying device3comprises a rail element8and a plurality of carriages9guided on this rail element8. The movement path of the receptacles for the screws is substantially O-shaped, with two straight, oppositely disposed sections10,11and two curved sections12,13which each deflect the movement path of the carriages by 180°. The two inspection units4,5are disposed on the straight section10of the movement path and thus of the conveying path of the screws. The arrangement of the inspection units along the straight section of the conveying path has two advantages, which are explained in more detail in the following.

Each of the two inspection units4,5comprises a sensor14,15. The sensor14of the first inspection unit4is a CCD camera for visual inspection of the individual screws. The sensor15of the second inspection unit5, on the other hand, is an eddy current measuring head for detecting cracks in the individual screws. Since the two inspection units4,5are disposed along the straight section10of the conveying path, the spacing between the individual inspection specimens and the respective sensor14,15along the measuring section that lies on the straight section of the conveying path does not change. There is consequently no need to factor out artifacts that occur because the spacing between the inspection object and the sensor changes as a result of a curved measuring section.

The conveying device3is constructed in a modular manner from a plurality of segments which are connected to one another in a releasable and interchangeable manner. The shown conveying device3consists of two head-side segments16, which carry the curved sections of the rail element8. The curved sections of the rail element8each bring about a deflection of 180°. Provided between said two head-side segments16are two straight segments17, each of which carries two oppositely disposed straight rail sections. The straight segments17of the conveying device can be removed from or inserted into the inspection system1with a few simple steps. The overall length of the inspection system, in particular the length of the straight sections of the conveying path, can thus be adapted on site to the respective inspection task. Depending on the length of the straight section of the conveying path, more or fewer inspection units4,5can be held on the straight conveying path, making it possible to carry out a wide variety of inspection tasks.

Since the two segments17both comprise two oppositely disposed straight rail sections, when a straight segment17is added, inspection units can respectively be held on the opposite sides.

One of the curved segments16also carries a drive motor18for the carriages9of the conveying device1. The individual carriages9are driven via a toothed belt guided over two timing pulleys19,20. Each of the carriages9is hooked into the toothed belt.

Each of the carriages9is guided on the rail element8by means of a roller26. The rail element8extends through two of the four rollers26.

In the shown embodiment, as depicted inFIG.4, each of the carriages9carries four receptacles21for exactly one respective screw. Each of the receptacles21comprises an elongated hole23as a perforation in the sense of the present application in a support surface22. In the shown embodiment, all of the elongated holes23are provided in the same support surface22. Each of the elongated holes23comprises an opening toward the edge of the support surface22, so that the screws can be inserted with their cylindrical portions through this opening into the elongated hole23. The undersides of the screw heads then rest on the support surface22. During the inspection, i.e., when the screws are moved past the sensors14,15of the inspection units4,5, the support surface22is aligned substantially horizontally, as can be seen in particular in the illustration ofFIG.4. The horizontal position of the support surface22is referred to in the sense of the present application as the first position of the support surface22.

As stated above and illustrated in the figure, the screws are fed to the receptacles21driven by gravity on the feed bevel6of the feed device2. The undercarriage24of the carriage comprising the receptacles and in particular the support surface22is configured such that it can pivot about a pivot axis relative to the upper carriage25comprising the rollers26. The undercarriage24is pivoted in such a way that the support surface22moves from the first position into a second position. The second position of the support surface22can be seen in one of the carriages8inFIGS.3and5. In this second position, the support surface22extends inclined relative to the horizontal, whereby the slope of the support surface22in the second position is adapted to the slope of the feed bevel6of the feed device. The screws from the feed bevel6can thus slide off the screw heads onto the support surface22without there being a discontinuity on which the screws can get stuck.

The feed is less prone to error. The undercarriage24and thus the support surface22are pivoted at the feed position7with the aid of an actuating cam27, which is fixedly disposed at the feed position7. When a carriage9reaches the feed position7, the actuating cam27pushes the undercarriage24from the first position into the second position and, when it leaves the feed position, the undercarriage and thus the support surface22pivot driven by gravity from the second position back into the first position. In the first, horizontal position, the inspection objects are inspected at the inspection units4,5.

FIGS.6and7illustrate the modularity of the inspection system1according to the invention. The inspection system1shown in bothFIGS.6and7is the same system in two configurations. The system in the configuration ofFIG.7has been expanded by an additional inspection unit28compared to the configuration shown inFIG.6. In the configuration ofFIG.6, the inspection system comprises the two head-side segments16of the conveying device and exactly two straight segments17. The two inspection units4,5already shown inFIG.1are held on the two straight segments17. The reconfigured system ofFIG.7, on the other hand, comprises three straight segments17of the conveying device, so that the further inspection unit28is held on the third segment. Due to the modularity of the conveying device3, the inspection system can be adapted to a wide variety of different inspection requirements.

FIG.8shows a plan view onto the inspection system ofFIGS.1-3in a block diagram. In addition to the mechanical components, the block diagram schematically shows the elements for controlling the inspection system1.

The feed of the separated inspection objects, here screws, takes place as described above at a feed position7. The inspection system1comprises two inspection units4,5, which are disposed at a first inspection station50and a second inspection station51on the conveying path of the conveying device3. The respective inspection positions52,53are defined by the stations50,51and the configuration of the inspection units4,5. The actual inspection, i.e., the sensing of the inspection objects, is carried out at these inspection positions. Viewed in the conveying direction54, the inspection positions are behind the feed position7.

As stated above, the inspection system1comprises two ejecting device55,56, which are respectively disposed at an ejection position57,58.

The two inspection units4,5both comprise an inspection controller59and a data interface60in the form of a plug connector. This data interface60is referred to in the sense of the present application as a second data interface. When the inspection units4,5are held at the respective inspection station50,51, the plug connectors, are plugged into complementary plug connectors61on the remaining part of the inspection system. In the sense of the present application, these complementary plug connectors61constitute the first data interfaces.

The first data interfaces61are connected to other elements of the inspection system via a bus line62. A system controller63, the ejecting devices55,56and the drive18of the conveying device3are connected to the bus62as well.

In the shown embodiment, the system controller61takes on only the error management and the administration of the system1. The system controller61in particular takes on the control of the drive motor18, i.e., the specification of the conveying speed.

In the shown embodiment, the system parameters, such as the speed of the inspection objects along the inspection path and the occupancy of the receptacles of the conveying device3, are stored in advance in the inspection controller59of each inspection unit4,5. When an inspection unit4,5is inserted for the first time at the respective inspection station50,51, the inspection controller59detects at which inspection station50,51and thus at which inspection position52,53it is disposed.

For this purpose, the shown embodiment uses an identifier of the respective inspection station50,51, which is encoded in the form of the pin configuration of the sockets of the plug connectors61of the first data interfaces.

From the inspection position52,53, the respective inspection controller59calculates how long it takes for an inspection object inspected by it to be conveyed from the inspection position52,53to the ejection position57or58. The respective inspection controller59thus has all the information that enables it not only to carry out the actual inspection, but also to implement the result of the inspection by ejecting the respective inspection object at the correct ejection position57,58.

In the shown embodiment, items that have successfully passed the inspection with the two inspection units4,5are ejected by the ejecting device56which is second in the conveying direction54. Conversely, items that have failed the quality inspection are ejected from the first ejecting device55.

Assuming the first inspection unit5detects an item that has failed the inspection, the inspection controller59issues an ejection command directly to the first ejecting device55via the plug connectors60,61of the first and second data interfaces and the bus60. The ejection command is generated at a point in time at which the inspection object has reached this first ejecting device55.

For the purpose of the original disclosure, it should be noted that all of the features as they become apparent to a person skilled in the art from the present description, the drawings and the claims, even if they have been specifically described only in connection with specific other features, can be combined both individually and in any combination with other features or groups of features disclosed here, insofar as this has not been expressly excluded or technical circumstances make such combinations impossible or pointless. A comprehensive, explicit presentation of all conceivable combinations of features is omitted here solely for the sake of brevity and legibility of the description.

Although the invention has been presented and described in detail in the drawings and the foregoing description, this representation and description is merely an example and is not intended to limit the scope of protection as defined by the claims. The invention is not limited to the disclosed embodiments.

Modifications of the disclosed embodiments will be obvious to those skilled in the art from the drawings, the description and the appended claims. In the claims, the word “comprise” does not exclude other elements or steps, and the indefinite article “a” does not exclude a plurality. The mere fact that certain features are claimed in different claims does not preclude their combination. Reference signs in the claims are not intended to limit the scope of protection.

REFERENCE SIGNS

1Inspection system2Feed device3Conveying device4,5,28Inspection unit6Feed bevel7Feed position8Rail element9Carriage10,11Straight section12,13Curved section14,15Sensor16Head-side segments of the conveying device17Straight segments of the conveying device18Drive motor19,20Timing pulley21Receptacle22Support surface23Elongated hole24Undercarriage25Upper carriage26Roller27Actuating cam50,51Inspection station52,53Inspection position54Conveying direction55,56Ejecting device57,58Ejection position59Inspection controller60Plug connector of the second data interface61Plug connector of the first data interface62Bus63System controller