JPH04201138A - Manufacture of automobile - Google Patents

Abstract

PURPOSE:To simplify a production management system by printing production indication information, necessary to an assembly process, on a work by using ink removable in a pairing process and dissolving the information of removal after completion of assembly. CONSTITUTION:In a heading printing process 21 and an assembly printing process 22, production indication information is printed on each part and semiproduct. Ink dissolved in a solvent used at the pretreating stage of a painting process 24 is used as ink used for the printing. The production indication information is simply read by various devices, such as a reflection type photoelectric switch, a visual device, and a bar code reader, and a worker and a production management system is simplified. After completion of assembly, the printing is dissolved for removal at a degreasing process at the pretreatment stage of the painting process. This method manufactures a vehicle at a low cost with high workability.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention manages information on workpieces in the car body assembly process, including the process of manufacturing workpieces such as parts and panel materials that make up the car body. This invention relates to a method for manufacturing automobiles.

(Prior Art) Automobile body assembly involves manufacturing parts and panel materials, that is, works, for predetermined parts of an automobile body through a predetermined process (heading process) such as pressing, rolling, or forging. This is done by joining a large number of workpieces together using spot welding or the like during the vehicle body assembly process.

For example, in the flow main process as a car body assembly process,
The engine compartment and front floor Akhlov parts are either joined together, or these workpieces are manufactured by joining multiple workpieces that have been previously produced in a heading process.In fact, to manufacture the car body, heading By combining n types of workpieces manufactured in the process, m types of semi-finished products, such as engine compartments, etc., are manufactured, and these m types of workpieces are further combined to assemble two types of vehicle bodies. The vehicle body, ie, the white body, manufactured through the vehicle body assembly process is further sent to a painting process, and after being painted, is sent to a vehicle assembly process that includes a bottle making line and the like. Therefore, the number of various semi-finished products such as engine compartments that are currently being manufactured may number in the hundreds, and the number of possible combinations of these semi-finished products is enormous. . For this reason, it is necessary to correctly combine these workpieces, and combination instructions, that is, production instructions, and management and identification of parts are extremely important when manufacturing vehicle bodies.

An overview of the current production system is explained with reference to Fig. 8. Various panel materials are forged using processing machines such as presses. It is assumed that units of 1 to n types of parts are manufactured. Several of these parts are assembled using a spot welding machine or the like to produce panel-shaped semi-finished products of a-m types. Furthermore, these semi-finished products a-m
are assembled to produce A-Z type semi-finished products that are more advanced in assembly, that is, vehicles in this case. These Z type vehicles undergo chemical conversion treatment and painting in the next painting process,
Transported to a repair line, etc.

FIG. 9 schematically shows how three types of semi-finished products, indicated by symbols a to C, are assembled using the assembling apparatus 10 from four types of parts. For example, assuming that panel materials are assembled in the order of C, b, and a using four types of parts 1 to 4, the production control computer 11 sends information to each device via the control device 12. A control signal is sent to the In response to this control signal, the component input device 13 transports the components 1, 3, and 4 to the assembly device 10 in order to assemble the panel material C, and sequentially selects a predetermined component from the assembly device 10 according to the production instruction data. The panel materials are transported and assembled in a predetermined order. Before the parts 1 to 4 are carried into the assembly device 10, the discrimination device 14.15 discriminates whether or not the instructed part has been carried in. If the instructions are correct, the assembly work is carried out using a welding device or the like. This is done automatically, and if it does not follow the instructions, it issues information to the effect that it is an error and takes steps to return it to normal. After the types of these semi-finished products C-a are determined by the discriminating device 16, they are transferred to the next assembly device 1.
Sent to 7.

(Problems to be Solved by the Invention) As mentioned above, when manufacturing a vehicle by assembling a large number of parts and panel materials, it is difficult to distinguish the types of parts 1 to n and panel materials a to m. This is an important condition.

In order to distinguish these types, there is a method that uses a visual device to identify characteristic parts of parts and panel materials, but this method can only identify parts whose shapes are large relative to each other. This method is difficult when discriminating parts that are different but have similar shapes or are complex. For relatively small parts, there is also a method of measuring their length, size, etc. However, this method is not very effective for large parts or semi-finished products, such as car bodies, because not only the measuring device is large and expensive, but also the parts that can be measured are complicated.

Still other identification methods include checking the presence or absence of holes, etc. in parts to determine the type. In the case of parts, holes or the like are often formed to facilitate assembly, and it is also common practice to examine these holes for identification. but,
These holes are often small or located in complex locations inside the component, often complicating the identification device.

For any of these methods, is it necessary to improve positioning accuracy for assembling parts and panel materials?
Since the shape changes as assembly progresses, it has traditionally been necessary to devise a discrimination device for each stage of machinery and process. Therefore, the discrimination device has become complicated and expensive.

Conventionally, data and information about each component, etc., is written into the components and panel materials to be discriminated by the various discriminating devices described above. This writing method includes marking the parts, etc., punching information into the parts etc. using a bar code in advance, or writing the information with a laser or the like. However, all of these methods cause damage to parts, etc., so they may damage parts that are not visible from the outside when the product is manufactured, such as the panel material installed on the inside or the inner surface of the panel material. Information needs to be recorded. Therefore, there are problems in that not only the parts that can be used are limited, but also the shape of the reading device becomes complicated.

The above-mentioned problems can be avoided by recording information on parts and panel materials using magnetism, but this writing method cannot be applied when the parts are made of materials other than iron, such as aluminum alloy. Further, there is a problem that not only is it difficult to improve reliability, but also that the writing density of information is low, so that the range to be written becomes wide.

Stickers and I with barcode information written on parts, etc.
It has also been attempted to attach something like a D-card to a component or panel material, but with this method it is necessary to collect the sticker etc. afterwards. Furthermore, when collecting this sticker, a device for automatically removing it becomes complicated and difficult. Furthermore, since ID plates and the like are expensive, it is necessary to construct a system for collecting and reusing them.

An object of the present invention is to solve the above-mentioned problems in the conventional method of manufacturing an automobile body, and to provide a method of manufacturing an automobile that can improve production efficiency by allowing workpiece information to be written in any part of the workpiece. shall be.

(Means for Solving the Problems) To achieve the above object, the present invention includes a heading process for manufacturing workpieces such as parts, an assembly process for joining a plurality of the workpieces to each other, and a process for joining the workpieces after assembly. A method for manufacturing an automobile body, which includes a painting process, in which production instruction information necessary in the assembly process is printed on the workpiece using ink that is dissolved by the pre-painting treatment material in the painting process, and a process after the assembly is completed. The method of manufacturing an automobile includes a step of dissolving and removing the printed information in a pre-treatment stage of the painting step.

(Function) For workpieces such as parts and panel materials that make up automobile bodies,
Production instruction information for the workpiece is printed using ink that dissolves in the pretreatment stage of the painting process. When assembling workpieces, the type of workpiece is determined by the reading device and the worker, and production control is performed.
After assembly is completed, the production instruction information is dissolved and removed during the painting process.

Therefore, production instruction information can be recorded at any location on the workpiece using a simple device, and not only can the operator
The configuration of the information reading device is also simplified.

(Example) Hereinafter, a method for manufacturing an automobile according to the present invention will be described in detail with reference to the drawings.

As is well known, an automobile body has multiple assembly processes such as a floor main process, a main body process, and a metal line process.In the floor main process, the engine compartment and front and rear floor panels are assembled, and the floor main process is completed. It is formed. Then, body side panels, roof panels, etc. are assembled on this main floor in the next main body process. Furthermore, in the metal line process, door panels, roof panels, etc. will be assembled. In addition to these assembly steps, the engine compartment and roof panel itself are also manufactured by previously assembling multiple parts in other assembly steps.

In this way, an automobile body is manufactured by assembling a plurality of minimum unit parts to produce a semi-finished panel material, that is, an automobile body component H, and then assembling a plurality of vehicle body component parts with each other. In some cases, the semi-finished product itself can be manufactured with a small number of manufacturing steps, and in other cases, it can be manufactured through a large number of manufacturing steps. These parts and panel materials are collectively referred to as the workpiece.

FIG. 1 is a diagram showing the basic concept of the method of manufacturing an automobile according to the present invention. In the forging printing process 21, for example, the smallest unit parts constituting an automobile body are manufactured by pressing or the like. Then, for each component, component information is printed at a predetermined position. The parts that have passed through the forging printing process 21 are sent to the assembly printing process 22, where the type of the part is determined and assembled into semi-finished products such as panel materials. Information on the semi-finished products is printed on the semi-finished products. be done. Normally, this semi-finished product is further assembled with other parts in the final assembly step 23 to produce a semi-finished product with more advanced assembly. Note that in this assembly process as well, the type of semi-finished product is determined.

The number of assembly processes varies depending on the members that make up the vehicle body, and a predetermined semi-finished product may be formed through a large number of assembly processes. However, in Figure 1,
Only the initial assembly step 22 and the final assembly step 23 are shown. After the product, that is, the vehicle body, has been formed through the final assembly process 23, it is transported to a painting process 24.

In the heading printing process 21 and the assembly printing process 22,
As described above, parts information is printed for each part or semi-finished product. The ink used for printing is manufactured from a material that dissolves in the solvent used in the degreasing process of the painting process, which has a pretreatment process consisting of a degreasing process, a cleaning process, a chemical conversion process, and a cleaning process. used. The panel materials that make up the car body are coated with oil, and some use synchro (zinc ridge bramer), so printing is possible even in such cases, and it can be used in the pre-processing process. Select an ink that dissolves in the solvent.

Printing methods include a method of spraying ink and a method of using an inkjet printer, and furthermore, a stamp method having a spherical printing surface may be used. In this case, since the printing surface is spherical, printing can be performed even if the component or panel material is not flat. As for the types of information that can be recorded, various types of information such as Nokuichi code, characters such as kanji, and even specific symbols can be used. If characters are used, the type of work can be determined by the operator in addition to the reading device.

The information printed in this way is used in the assembly process 22.2.
3. It is necessary to read the information before carrying it into the painting process, and various types of devices such as a known reflective photoelectric switch, a visual device, and a barcode reader can be used as this discrimination device.

FIG. 2 is a schematic diagram showing the entire production system for controlling the manufacturing apparatus of the present invention, in which parts, that is, workpieces, are manufactured by the manufacturing apparatus 21a in the forging process 21 according to instructions from the production control computer 30, and the manufactured parts are For each part, predetermined part information is printed by the printing device 21b in response to instructions from the computer 30. During the shipping process 31 and the delivery process 32 of the parts carried out from the forging process 21, the part information already written is read by a reading device such as the above-mentioned visual device, and the information is transmitted to the production computer 30. Thereafter, in the assembly steps 22 and 23, the shipping step 33, and the delivery step 34, information about the parts and panels is similarly read by the reading device and transmitted to the computer 30.

Production computer 3 is installed for each process equipment.
0, a predetermined work signal is sent depending on the type of workpiece.

When the painting work is completed, the product is assembled with many parts and panels, so the density of necessary information is high, so in the data conversion process 35, the ID plate used conventionally Replace it with an information management method such as Therefore, until the final process 36, such as a repair process after painting, information is read and managed using an ID plate or the like.

FIG. 3 is a diagram showing an example of application of the present invention, and this diagram shows a state in which two panel members are joined together by spot welding to produce one semi-finished product. In this case, in the process of forming the panel material in advance, the above-mentioned ink is used in the area to be spot welded, and a mark 40 is placed at the dot position.
In the illustrated assembly process, the operation of a robot 43 having a spot gun is controlled by a control signal from a control device 42 while reading the striking point position marked by a visual device 41. Therefore, in this case, there is no need to teach the robot 43 the welding point position, and even if the welding point position or car model changes, spot welding can be reliably performed at the predetermined position simply by changing the marking position. It is possible to do this.

FIG. 4 is a diagram showing still another application example of the present invention, in which marks 44a and 144b may be added with the above-mentioned ink to indicate the type of workpiece to the operator according to the vehicle type and destination. good. The marks 44a and 44b have different colors. For example, if an indicator light (not shown) is used to indicate the relationship between the color and the type of workpiece, the operator can visually check the marks 44a and 44b to determine the type of workpiece. It is also possible to judge.

In another application example shown in FIG. 5, a so-called eye mark 45 is attached to the workpiece in order to indicate to the worker the mutual set positions of the parts when assembling a plurality of parts. This allows the worker to easily determine the top, bottom, left, right, etc. of the workpiece, making assembly easier.

FIG. 6 is a diagram showing still another application example, and shows a state in which the panel members are positioned on a predetermined jig when assembling the panel members together. In this case, when the panel material is sent from a drop lifter (not shown) in the direction shown by arrow A and placed on the positioning jig, the mark 46 previously attached to the panel material is transferred to the jig with rough positioning accuracy. The reading device 47 detects the position of the panel material. Then, the panel material is positioned at a predetermined position by a device 48 that finely adjusts the panel material in the vertical and horizontal directions.

Conventionally, this type of positioning is performed using an NC locator to accurately position the panel material with respect to the jig, but it is now possible to position the panel material at a predetermined position using a simple device without using such a positioning device. can.

Furthermore, in another application example shown in FIG. 7, one panel material is assembled through assembly steps A to C each having three stages. In the assembly process A, assembly is performed at any of stages A1 to A3, similarly, in the assembly process B, assembly is performed at any of stages B1 to B3, and in the assembly process C, assembly is performed at any of stages C1 to C3. Therefore, there are theoretically 27 combinations of the assembly processes shown in the figure.
For example, if the illustrated panel material W is assembled in stages A1, B2, and C2, a predetermined mark 50 will be attached to the panel material W to indicate the history of each stage.

As a result of measuring the assembly accuracy of the completed panel material W, if it was not assembled to the specified accuracy, steps A-C
It is possible to discover at which stage the assembly device is defective. As a result, the present invention has the advantage that it is also possible to manage the history of completed vehicles and completed workpieces.

(Effects of the Invention) As described above, according to the present invention, information can be recorded on a workpiece using ink that can be removed during the painting process, so information can be recorded at an easily visible position on the workpiece. The device that reads the information has a simple structure. Further, since the information can be easily viewed by the workers themselves, the vehicle production management system becomes simple, and vehicles can be manufactured at low cost and with good workability.

[Brief explanation of the drawing]

Fig. 1 is a manufacturing process diagram showing the basic concept of the present invention, Fig. 2 is a process diagram showing the schematic structure of the production control system in the manufacturing method of the invention, and Fig. 3 is a welding assembly process according to an application example of the invention. FIG. 4 and FIG. 5 are front views showing still another application example of the present invention, FIG. 6 is a perspective view showing still another application example of the invention, and FIG. 7 is a front view showing still another application example of the present invention. FIG. 8 is a process diagram showing an assembly process according to an application example of the present invention, FIG. 8 is a process diagram showing a conventional vehicle body assembly process, and FIG. 9 is a process diagram showing a schematic structure of a conventional production management system. 21... Forging printing process, 22... Assembly printing process,
23... Assembly process, 24... Painting process. Patent applicant Nissan Motor Co., Ltd. agent Patent attorney 8 1) Mikio (and 1 other person) Figure 6 BC

Claims (1)

[Scope of Claims] A method for manufacturing an automobile body, comprising: a heading process for manufacturing workpieces such as parts, an assembly process for joining a plurality of the workpieces to each other, and a painting process for painting the workpieces after assembly, A process of printing production instruction information necessary in the assembly process on the workpiece using ink that is dissolved by the pre-painting treatment material in the painting process, and dissolving the printed information in the pre-treatment stage of the painting process after the assembly is completed. A method for manufacturing an automobile, comprising a step of removing.