DE3102779A1 - DEVICE FOR COATING, IN PARTICULAR FOR SPRAYING COLOR ON WORKPIECES - Google Patents

Description

Patent attorneys Dr. tar. nat. Thomas Berendt

Di.-Ing. Hans Leyli Luclle-Grahn-Str! 38 - D 800Q Munich 80

Our reference: A 14 Lh / fi

CHAMPION SPARK PLUG COMPANY
900 Upton Avenue
Toledo, Ohio, USA

Device for coating, in particular for spraying Paint on workpieces

- V- G. Champion Spark Plug Co.

- A 14 439 -

description

The invention relates to a device for coating, in particular for spraying paint onto workpieces that are guided horizontally past a spray gun that can be moved vertically back and forth.

In many cases it is desirable to use a paint spray system with which the paint is sprayed onto workpieces while they are being transported on a conveyor system. With one form of training are one or more spray guns mounted on a carriage that is vertical or in a direction transverse to the direction of movement of the Workpieces is moved back and forth. When the spray gun sweeps a section of the surface of the workpiece, it is switched on, to provide the workpiece with a coating.

Various types of controls have been used in the past for and trailing spray devices have been proposed. US Patents 3,593,308 and 3,646,521 relate to control circuits for and forward sprayers. The workpieces are guided past a vertical row of photocell detectors before they enter the spraying station. The detectors generate data on the vertical and horizontal dimensions of each workpiece. the Data of a workpiece are processed digitally and stored in a memory matrix for controlling the reciprocating Spray head when the workpiece passes through the spray station. U.S. Patent 3,989,003 relates to a modified controller for a reciprocating spray device placed close to a horizontal conveyor for the work pieces. When a Workpiece enters an input station, an operator gives data on the position, type and desired color for the workpiece into the system. This data is stored in a memory until the object reaches the spray station.

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At this point, the data entered by the operator will be included compared to preprogrammed information. If there is a match, the spray guns in each spray station are through the preprogrammed information causes you to move into the correct position »whereupon the spray guns are activated to to spray the workpiece while it is transported past the spray device.

According to the invention is a novel and improved device for Controlling a plurality of reciprocating sprayers, such as paint sprayers, are provided to sequentially apply workpieces coating that are transported on a conveyor. First, a code for workpiece identification and a code for the Color entered into the system, either automatically or manually, by an operator while the workpiece is still upstream from the first spray station. These data are entered in series into a memory, where the data entered first can also be read out first (first-in, first-out memory). The system comprises a computer provided with a main memory which stores a number of XY matrices representing the represent horizontal and vertical coating patterns of a number of different parts. While every part in the Injection station is transported, the identification data for this part are read out from the row in this memory. These data cause the XY matrix for the identified part to be transferred to a temporary memory in a spray station controller, that of the first reciprocating spray gun is assigned along the conveyor. The spray station controller can be a separate unit that moves close to the reciprocating Device can be arranged, or it can be part of the main controller.

The workpiece is then coated while it is at the first spray device over! The XY matrix for the special

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The workpiece is then used by the microprocessor to control the spraying station transferred for each subsequent reciprocating spray gun along the conveyor while the workpiece is in a subsequent spraying station is transported. With this arrangement, a workpiece is automatically coated with different layers while it is being transported through the successive spraying stations. Or it can have a different pattern to cover different ones Parts of the workpiece from the main memory into the spraying station control with the associated memory for each of the successive spraying devices be transmitted. Several different workpieces can be put through the different spray devices at the same time are coated, which are arranged in the various spraying stations along the conveyor. The individual spray devices do not need to be synchronized with each other, since each spray device is operated by a spray station controller, the temporarily stores an XY spray pattern matrix for the workpiece being coated by the spray device at the moment. If desired, the individual spray devices can be designed so that an automatic color change between successive Workpieces takes place and that the system from the previous one The paint is cleaned automatically before a new spraying with a new color begins.

The invention is therefore based on the object of creating an improved control for reciprocating spray devices, which are arranged next to a conveyor for the workpieces.

A number of different workpieces are to be coated may be transported as they are sequentially transported past a plurality of reciprocating spray devices.

Exemplary embodiments of the invention are explained below with reference to the drawing, in which

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1 shows a part of a vehicle body in side view, which is transported past a reciprocating spray device will.

Figure 2 shows an XY matrix for the spray pattern for the vehicle according to Fig. 1.

Fig. 3 shows schematically a block diagram of a controller for back and forward spraying devices according to the invention.

1 shows a spray station 10 for coating a workpiece, for example an automobile body, while it is being transported on a conveyor 12. The spraying station 10 is provided with a reciprocating spray gun 13 * which coats the workpiece 11 while it is being transported on the conveyor 12. The spray device 13 may be of known construction and may include a carriage 14 _s on which a plurality of paint spray guns 15 are mounted. _{Other types 9,} for example powder spraying devices, can also be mounted on the slide 14 instead of the spray guns 15. A suitable drive, not shown, is provided for the slide 14 in the vertical direction, as indicated by the arrow 16. Simultaneously with the up and down movement of the slide 14, the workpiece 11 is moved horizontally past the spray guns 15, as indicated by the arrow 17. After the previous workpiece has been coated and before the workpiece 1t reaches the spray head 13, an XY matrix corresponding to the areas of the workpiece 11 to be coated is entered into a spray station controller and memory 18. The controller and the memory 18, which are also fed with the current position data for the workpiece 11 and, if desired, also for the carriage 14, selectively switches the individual spray guns 15 on and off while the workpiece 11 is moved past the spray head 13 in order to achieve the Coating workpiece 11 evenly according to the XY matrix. The individual spray guns 15 are only switched on until they have an upper

Paint over the surface section of the workpiece 11 that is to be coated. In the case of an automobile body, for example, the individual spray guns 15 are switched off while they are opening Paint over the workpiece 15, e.g. a window opening 19. Switching the spray guns on and off when painting over openings in the workpiece is of course dependent on the response time that is required to switch the spray guns on and off. Some Have coating equipment such as powder coating equipment a relatively long response time compared to liquid paint spray guns.

Fig. 2 shows an example of an XY matrix 20 for controlling the spray head 13 for covering the workpiece II. The matrix 20 has the Shape of a grid that is divided into a given number of vertical and horizontal surfaces. The number of vertical and horizontal surfaces is determined by the storage capacity of the controller and the memory 18, as well as an assigned main memory, which is described below. The matrix 20 can have a resolution or an array of 128 vertical areas or columns and 256 horizontal ones Have faces or rows. However, the matrix can be adapted to any desired division or resolution. For example, if the matrix 20 is is to cover a pattern with 8 x 20 feet or 2.4 x 6.0 m, a vertical resolution of 19.5 mm and a horizontal resolution of 24 mm in the matrix 20 can be selected. The matrix 20 provides information about when the individual spray guns 15 are switched on and should be switched off while the workpiece 11 is being transported past the extrusion head 13. One data bit is for everyone Area of the matrix 20 is stored which corresponds to an area of the workpiece 11 to be coated. Furthermore, a data bit can be divided into sections the XY matrix 20, which immediately precede or lag the workpiece 11, in order to ensure a uniform coating of the workpiece 11 while it moves past the spray head 13 will.

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Figure 3 shows a detailed block diagram for a control system according to the invention for actuating a plurality of movable up and down Spray devices 13a, 13b, 13c to 13i. The sprayers 13a to 13i are arranged in individual spraying stations 10a to 10i at intervals along the conveyor 12 to to coat a series of transported workpieces one after the other. Each spray device 13a to 13i can be provided with a vertical Encoder 26a to 26i be equipped, which generates a signal that the current vertical position of the corresponding spray devices 13a to 13i indicates. Each signal from the vertical encoder is applied to the associated spray station controller 18a to 18i. The controls and memories 18a to 181 for the spray stations 10a to 10i are each either connected to a main control 27 or form one Part of this controller, which is conveniently a microprocessor, such as the TMS9900 CPU model, manufactured and sold from Texas Instrument Company. The functions of the main control 27 and the individual controls 18a to 18i can but can also be carried out by a digital computer for general purposes, which is used in full or in part for this purpose. The main control 27 contains memory capacity for storing XY matrices, such as the matrix shown in FIG. 2 for the spray pattern for each of a plurality of different workpieces produced by the Spray devices 13a to 13i are to be coated. The XY matrices are stored in read-write memory and can be entered and / or via a keypad (not shown) that are part of a program station and display device 28 is. A station 29 for a manual scheme is also connected to the main controller 27. Data on Art the workpieces identifying each of the successive workpieces on the conveyor 12 are entered through the station 29 along with data, if necessary, indicating the color, with which each of the successive workpieces is to be sprayed. The color data can be entered for each workpiece or only when the color is changed. The data about the type of workpiece

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can be done in station 29 either manually with the aid of a keypad (not shown) or by other means, such as a card reader that reads the data from a punched card for each workpiece. The station 29 can, on the other hand, be replaced by an automatic identification system which Photoelectric elements can be included for observing each workpiece on the conveyor 12, as well as circuits that point to the unique address the physical geometry of each workpiece and generate digital data that identify that workpiece. Automatic workpiece identification systems of this type are known. The data on type and, if applicable, color for each workpiece are, regardless of whether they are entered manually via the station 29 or via an automatic station, in a memory (first-in, first-out memory) stored in the main controller 27. This type of memory allows the data stored in the same sequence in which the corresponding workpieces are transported to the spraying stations.

The main controller 27 also has an input from a sensor 30, which is positioned adjacent to the conveyor Ϊ2. The sensor 30 may be an optical sensor such as a photodetector that generates an output when each of the workpieces is up to one is transported at a predetermined point at which a light beam is below »- is broken. Or the sensor 30 can be a mechanical switch that is operated by each of the workpieces or by a bracket that supports the Workpieces supported on the conveyor 12, is triggered when the respective workpiece is moved past a predetermined point. The main controller 27 also has an input from an encoder 31, which is connected to the conveyor 12. The encoder 31 generates a signal every time the conveyor 12 increases by a predetermined small amount Step forward. By counting output pulses from the encoder 31 after a workpiece passes the predetermined position of the sensor 30 the exact position of the workpiece is precisely tracked while the workpiece is successively moved past the injection stations 10a to 10i will.

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When a workpiece passes the sensor 30, the main controller follows 27 continues to show the position of this workpiece while it is successively moved past the injection stations 10a to 10i. When the workpiece reaches the first spraying station 10a, the type and color data for this workpiece from the memory in the main control'27 read out. The main controller 27 then searches the XY matrix for the Workpiece, based on the data identifying the type of workpiece and transmits the XY matrix and the color data to the spray station control and memory 18a for the spraying station 10a. The spray station control 18a, which also consists of a separate microprocessor can consist of an integrated design, or which can be part of a computer with the main control, stores the transmitted Data in temporary storage. Before a workpiece in a spraying station occurs and preferably immediately after the last workpiece has left this station, the main control compares also the color data for this workpiece with the color data of the previous one Workpiece that was coated in this spraying station. If there is a color change, the main control 27 becomes the spray station control causes a predetermined time sequence of signals to be applied to outputs 32a in order to activate solenoids for the color selection, for solvents and for cleaning air to operate the spray guns which are mounted on the spray head and the connection lines to purge all color and to add new color. The cleaning cycle and the color change take place according to a predetermined one Program stored in the main controller 27, such as in U.S. Patent 3,674,205. The cleaning takes place between two workpieces. If desired, changes to the cleaning times can be entered manually via the program station 28.

The staining program that consists of the XY matrix and the color data for a Workpiece is passed to the first spraying station control 18a if the workpiece to be coated corresponds to this data heard "still has a distance from the spray device t3a. The exit of the encoder 31, which is applied to the difr main control 27, is

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furthermore either directly or indirectly via the main control 27 each of the spray station controllers 18a to 18i are placed. The spray station control 18a is provided with a counter which counts pulses from the encoder 31 from when program data from the main controller 27 to the spraying station controller t8a. These data identify the exact location of the Workpiece while it runs through the spraying station 10a. However, a sensor or a limit switch can also be provided to indicate when the workpiece is in a predetermined position in the spraying station 10a. When this sensor or limit switch has been triggered, pulses from encoder 31 are counted, to track the position of the workpiece as it is passed through the spraying station 10a.

In one embodiment, the pulses are based on the position of the workpiece used by encoder 31 in spray station controller 18a to sequentially register each vertical column in the XY matrix to push when the corresponding area of the workpiece passes the spray guns 15a. In other words, if any Column of data corresponds to the dimension of 24 mm of the horizontal division of the workpiece, then the next column becomes the XY matrix shifted into the register every time the workpiece advances by this distance of 24mm. When the workpiece on the spray head 13a is passed through the output from the vertical encoder 26a which is given to the spray station controller T8a is identified, the vertical position of each of the spray guns 15a on the spray head 13a. The data bits in the places of the vertical Columns of data currently stored in the register correspond to the vertical positions of the individual spray guns t5a on the spray head 13a and they control the outputs 32a of the spray station controller t8a to selectively turn each of the spray guns 15a on and off. If the spray guns 15a are still in moving up and down in the vertical direction, the data columns in the XY matrix for the workpiece one after the other in the register synchronously

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entered with the transported workpiece. When the workpiece moved past the spray guns 15a, the entire matrix has been entered into the register, and at this point in time the memory in the spray station controller 18a is free. While the workpiece is then transported to the next injection station 10b is either the same XY matrix or a different XY matrix for another part of the workpiece is given from the main controller 27 to the spray station controller 18b, so that the spray guns are used 15b controls a.m spray head 13b. This is repeated in each of the following spraying stations 10c to 10i. It is noted that the Matrices, which are given to each successive injection control 18a to 18i, can differ for a workpiece if they are different Workpiece areas, such as the left side, roof, right side, etc. are coated or coated in the various spraying stations. be injected.

In another preferred embodiment of the spray control 18a to 18i the shift register is omitted. The XY matrix for a workpiece is stored in a memory for as long as it is Workpiece is in the spraying station. When the workpiece is transported past the spray guns, markings show for each spray gun on the spray head to the memory addresses that indicate the current position of the spray guns relative to the workpiece correspond. In this embodiment, the injection control can be made integral with the main control and the markings can store locations that correspond to the current positions of the Spray devices correspond to the XY matrix, address them directly in the main read and write memory in the main control.

Each of the spray heads 13a to 13i is controlled independently of the other spray heads. The distance between the spray heads 13a to 13i is not critical, so that each individual spray head 13a to 13i need not be synchronized with the others. There each of the spray heads 13a to 13i is controlled independently of the others, different types of workpieces can also be produced are coated or sprayed at the same time by the spray heads. Furthermore, the workpieces can be spaced arbitrarily on the conveyor since the main controller 27 determines the position of each workpiece on the - 11 -

Conveyor 12 with respect to the individual spray stations 10a to 10i tracked. Alternatively, a limit switch can also be provided at each spray station 10a to 10i. When a workpiece is in the Injection stations 10a to 10i enters, the limit switch gives a signal to the main controller 27 to set the XY matrix for this Select workpiece to control this spraying station.

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Claims (10)

Champion Spark Plug Co. - A 14 439 - Claims Apparatus for coating different workpieces which are moved in a predetermined direction on a conveyor, with a coating device, devices for moving the coating device to and fro in a direction essentially perpendicular to the predetermined direction, characterized by a first memory for storing data for a coating pattern for each of the different workpieces to be coated, a second memory for temporarily storing the data of the coating pattern on a workpiece which is immediately coated by the coating device, means for generating position data corresponding to the instantaneous position of a workpiece, control means responsive to address this positional data and the data for the coating pattern in the temporary memory to selectively turn the coating device on and off to produce a workpiece in accordance with its data for s to coat a coating pattern, a third memory through which data for identifying each workpiece can be sequentially stored, and by means which are responsive to this data sequence in the third memory in order to read out the data of the coating pattern of a workpiece from the first memory and to store the read-out data in the second memory while this workpiece is being transported to the coating device. 2. Apparatus according to claim 1, characterized by a plurality of coaters spaced along the conveyor, an equal plurality of second Store and control devices with a separate second 130051/0497 Storage and separate control devices for each loading device are assigned, further in that the means for generating position data have means to Generate positional data of each of the coating devices, and wherein the devices that respond to the data sequence respond in the third memory, means comprising the data of the coating pattern of a workpiece from the first To read storage device and sequentially store the read data in each of the second memories, which each of the successive coating devices are assigned along the conveyor when this workpiece is to each of the successive ones Coating devices is transported, so that this workpiece is successively coated while it is at each of the coating devices is transported past one after the other. 3. Apparatus according to claim 1, characterized by a plurality of coating devices, which at intervals arranged along the conveyor, an equal plurality of second storage and control devices, with one separate second memory and a separate control device, which are assigned to each coating device, wherein the Device for generating position data comprises devices for generating position data for each workpiece which is coated by a coating device, as well as for each coating device, furthermore the devices, which respond to this data sequence in the third storage device, comprise devices for storing the data for the coating pattern read out each workpiece from the first storage device when this workpiece is sent to a coating device is transported and to store the read-out data of the coating pattern in the second memory of each coating device is assigned so that each workpiece is successively coated while it is on the successive Coating devices is moved past. 130051/0497 4. Device according to one of claims T ₉ 2 or 3, characterized in that the third memory is a memory in which the data are read out in the same order in which they are entered (first-in, first-out memory) . 5. Device according to one of claims 1, 2 or 3, characterized by means for modifying the data for the coating pattern stored in the first memory are. 6. Apparatus according to claim 1, 2 or 3, characterized by devices for generating position data corresponding to the current position of the coating device, further in that the control means, which is responsive to the position data, both to position data of the workpiece and the coating device responds. 7. Device for coating various workpieces that move in a predetermined direction on a conveyor, with a coating device and means to the latter in a direction substantially perpendicular to the predetermined direction to move back and forth, g e k e η η ζ e i c h ne t through a first storage device to Storage of data for a coating pattern for each of the various workpieces to be coated, devices for Generation of position data according to the current position of a workpiece on the conveyor, second storage devices, in order to store data in sequence which identify each workpiece in turn, further control devices which are based on the Address position data of the workpiece, with the identification data in the second memory and the coating pattern data the coating device can be selectively switched on and off in the first memory in order to coat a workpiece while it is transported past the coating device in accordance with the stored data for the loading 1/0497 H. Layering pattern of this workpiece. 8. Apparatus according to claim 7, characterized in that da3 the control device comprises a third memory, devices which act on the identification data in the second memory respond to read out the coating pattern data for the next workpiece to be coated, and read them out To store data in the third memory, furthermore devices which are based on position data of this next workpiece respond and to the coating pattern data in the third memory to switch the coating device on and off, to coat this next workpiece while it is being transported past the coating device. 9. Apparatus according to claim 8, characterized by a plurality of coating devices which are reciprocable at the same time, further in that the Devices which act on the position data of the next workpiece and on the coating pattern data in the third Address memory, selectively turn each of the coating devices on and off to coat the next workpiece while it is being transported past this coating device. 10. The device according to claim 9, characterized by means for generating position data accordingly the positions of the coating device, and that the device based on the position data of the next workpiece responds, responds to both the position data of the workpiece and the coating device. 130051/0497