JP4974489B2 - Assembly accuracy measurement system - Google Patents

Description

  The present invention relates to an assembly accuracy measuring system for measuring assembly accuracy between two adjacent assembly parts constituting an intermediate finished product of a vehicle, and more particularly, an intermediate finished product to be assembled in a production line. The present invention relates to an assembling accuracy measuring system capable of measuring the assembling accuracy between adjacent parts efficiently and with high accuracy with respect to the total number.

  For example, in the quantitative measurement of the installation accuracy around the door of the vehicle body, 1 to 2 units are taken out from the production line every day and taken off line (offline). At present, the sensitivity is evaluated by measuring the gaps and steps between them. Here, examples of the construction of the vehicle body around the door include a fender and a front door, a front door and a rear door, a front door frame and a rear door frame, and a construction between the rear door and a side member.

  However, since the number of units produced on the production line can reach about 1,000 units, it is a big problem in quality control to represent such units with one or two vehicles and the accuracy of assembly of all vehicles. is there. Further, in the sensitivity evaluation of the worker described above, the inspection result varies depending on the skill of the worker, and it is difficult to obtain high reliability in the reliability of the evaluation result itself. In addition, since the number of inspections is extremely small, it is impossible to manage the tendency regarding the assembly accuracy, and it is impossible to grasp the degree (size) of the variation in assembly accuracy and the median value thereof. Therefore, based on the inspection results, it is impossible to grasp the assembly parts and parts assembly sites that should be managed intensively and to provide feedback. Therefore, even if the assembly accuracy of the assembled vehicle is measured, it is still a part in the production line. It did not contribute to the improvement of assembly accuracy.

Patent Document 1 discloses an invention relating to an assembling accuracy measuring method for measuring and managing with high accuracy without relying on an operator's sensitivity evaluation for assembling accuracy around a door of a vehicle. This is because a reference mark is attached to an arbitrary portion of the outer surface of the side panel and the side door in a posture in which the side door is assembled to the opening formed in the side panel, and the side panel and the side door including the reference mark are attached. After measuring the outer surface shape of the side panel with a 3D digitizer scanner, remove the side door from the side panel and measure the opening shape of the side panel with the 3D digitizer scanner. Then, using the reference mark as a reference, the assembly accuracy is measured by synthesizing the shape of the opening of the side panel and the shape of the peripheral edge of the side door with a computer.
JP 2002-2566 A

  According to the assembly accuracy measuring method disclosed in Patent Document 1, it is possible to measure the assembly accuracy around the door of the vehicle with extremely high accuracy. However, in this method, it is necessary to get off the vehicle in the middle of assembly from the production line, and further, to remove the assembled side door from the side panel, and to compare the scanner measurement results before and after removal, It takes a lot of time to measure the assembly accuracy. Furthermore, the number of intermediate vehicles extracted from the production line must be limited to a few, and the above-described adverse effects caused by representing a large number of vehicles with a small number of vehicle measurements cannot be eliminated.

  The present invention has been made in view of the above-described problems, and the assembly accuracy that enables efficient and high-precision in-line measurement of the component assembly accuracy of all the vehicles produced on the production line. The purpose is to provide a measurement system.

  In order to achieve the above object, an assembly accuracy measurement system according to the present invention is an assembly accuracy measurement system for measuring assembly accuracy between adjacent components in a plurality of assembly components constituting an intermediate finished product of a vehicle. A measuring unit that is positioned and fixed at a predetermined position on the production line and that measures a gap and / or a step in a measurement part between the adjacent parts; a conveying unit that conveys the intermediate finished product at a predetermined speed; And a command unit that outputs a measurement command to the unit. When the measurement command from the command unit is sent to the measurement unit, the measurement unit performs measurement based on the conveyance speed of the conveyance unit and the position of the measurement part. It is characterized in that a gap and / or a step of a part is measured.

  In the present invention, when an intermediate finished product of a vehicle is manufactured by sequentially assembling fenders, doors (front doors, rear doors), door frames, etc. in a production line, the assembly accuracy between adjacent assembly components is in-line. The present invention relates to a system for automatically measuring the total number. The time required for assembling the parts in each assembling site is about one minute, and the intermediate finished product is conveyed to the next assembling site by the belt conveyor simultaneously with the completion of the assembling. Therefore, the time for measuring the measurement part on the in-line needs to be performed in a very short time while the intermediate finished product is transported from any part assembly place to the next part assembly place, Since there are a plurality of measurement parts in one vehicle, it cannot be handled by visual inspection by an operator, and automatic measurement is an essential condition.

  Measurement points between any adjacent parts constituting the intermediate finished product are gaps and steps between the parts. Both gaps and steps between parts have a significant impact on the appearance of the vehicle, and if these gaps or steps are too large, it is difficult or impossible to assemble other parts at the completion stage of the vehicle. It will cause problems such as becoming. Therefore, it is preferable to measure both gaps and steps between parts, and by checking that the measurement results of both parts are within allowable tolerances at each assembly completion stage of each part, the vehicle is completed or completed. It is possible to avoid the occurrence of defects in the immediately preceding stage and to manufacture a completed vehicle whose appearance is not hindered by a large assembly error.

  The system of the present invention comprises a conveying means (for example, a belt conveyor) that constitutes a production line and conveys an intermediate finished product at a constant speed, an appropriate measuring means that is positioned and fixed at a predetermined position beside the conveying means, and a measurement It is generally composed of command means for issuing a measurement command so as to measure the measurement site. As the measuring means, for example, an optical sensor that emits an appropriate light wave can be used, the gap between adjacent parts can be measured by receiving the reflected light, and the level difference can be measured by the time lag until the reflected light is received. Can do.

  Usually, a plurality of measurement parts are set in an intermediate finished product of a vehicle. Therefore, when the intermediate finished product has been transported to an arbitrary part assembly site by the transport means, the parts are assembled within the required time, and the transport means starts moving at a constant speed. The speed of the conveying means is constant, and when the measurement command is issued from the command means based on this speed and the position information of the measurement part of the intermediate finished product, the measurement part is measured by the measurement means. For example, a measurement command is output from the command unit when assembly of any part is completed and the transport unit starts to move, and based on information in the storage unit (information on the speed of the transport unit and the position of the measurement part) The measurement part can be measured when the measurement part reaches the measuring means positioned at a predetermined position. When there are multiple measurement parts in the longitudinal direction of the intermediate finished product, measurement at each measurement part is performed at any time according to the separation between the measurement parts (separation in the conveyance direction of the intermediate finished product) and the speed of the conveyance means. Can be done.

  According to the above-described system, since both the gaps and the steps of the plurality of measurement parts can be automatically measured in a short time, it is possible to realize the total measurement on the production line in-line. By realizing 100% measurement, it is possible to accurately grasp the assembly capability (such as assembly accuracy) for each component assembly site, so that it is possible to centrally manage component assembly sites where assembly accuracy is undesirable. Become. In addition, a large number of quantitative data can be accumulated by measuring the total number, and the median value of the variation in assembly accuracy can be obtained based on such data. It is possible to construct a production line that can achieve accuracy.

  Another embodiment of the assembly accuracy measurement system according to the present invention is an assembly accuracy measurement system that measures assembly accuracy between adjacent components in a plurality of assembly components constituting an intermediate finished product of a vehicle. A measuring unit that is positioned and fixed at an arbitrary position on the production line and that measures a gap and / or a step in the measurement part between the adjacent parts, a storage unit that stores the position of the measurement part, and the intermediate Conveying means for conveying the finished product at a predetermined speed and command means for outputting a measurement command to the measuring means. When the measurement command from the command means is sent to the measuring means, the measuring means The gap and / or step of the measurement part is measured based on the transport speed and the position of the measurement part in the storage means.

  The present invention is an assembly accuracy measurement system in which the installation position of the measurement means is arbitrarily (movable), and in association therewith, a storage means for storing the position of the measurement site is further provided in the assembly accuracy measurement system described above. It is about. Other configurations are the same as those of the assembly accuracy measurement system described above.

  The speed of the transport means is constant, and this speed and the position information of the measurement part of the intermediate finished product are stored in the storage means. When a measurement command is issued from the command means, the measurement is performed based on the information in the storage means. The part is measured by the measuring means. For example, a measurement command is output from the command unit when assembly of any part is completed and the transport unit starts to move, and based on information in the storage unit (information on the speed of the transport unit and the position of the measurement part) It can be set as the structure by which measurement of this measurement site | part is performed when a measurement site | part arrives at a measurement means. When there are a plurality of measurement parts in the longitudinal direction of the intermediate finished product, the separation between the measurement parts (separation in the conveyance direction of the intermediate finished product) is stored in advance in the storage means, and the separation and the speed of the conveyance means Accordingly, measurement at each measurement site can be performed at any time.

  In another embodiment of the assembling accuracy measuring system according to the present invention, the measuring means comprises a laser sensor, and at least a plurality of the laser sensors are provided in the vertical direction, and the command means conveys an intermediate finished product. Measuring means controlled by a timer by turning on a limit switch at a predetermined part of the intermediate finished product or a predetermined part of the placing means for placing the intermediate finished product on the conveying means. Can measure a measurement part, and when there are a plurality of measurement parts on a vertical line, the plurality of measurement parts can be measured simultaneously by the plurality of laser sensors. To do.

  Here, as an embodiment in which a plurality of laser sensors are provided in the vertical direction, for example, a form in which a plurality of laser sensors are provided on a bar member extending in the vertical direction or installed so as to straddle the conveying means. There is a form in which a plurality of laser sensors are provided on the vertical member of the portal frame composed of the vertical member and the horizontal member. In the case of a gate-type frame, a structure in which a plurality of laser sensors are provided on both of the two vertical members constituting the frame, and even in the case of a bar member extending in the vertical direction, it is transported. By installing two bar members at positions facing each other through the means and providing a plurality of laser sensors on each of the bar members, the measurement parts existing on the left and right of the vehicle body which is an intermediate finished product can be obtained. It becomes possible to measure at the same time.

  Further, the command means for outputting a measurement command to the measuring means is a limit switch, and when the intermediate finished product is transported by the transport means, a placing means for placing the intermediate finished product on the transport means ( For example, a point of time at which a projection (for example, dog) provided at an appropriate position of the scale (ON) turns on the limit switch can be used as a measurement starting point. A measurement command from the limit switch is transmitted to a computer communicating with the limit switch, and a timer is controlled by inputting a time lag from when the limit switch is turned on until the measurement command is issued to the measuring means. The Rukoto. Since the length in the longitudinal direction differs for each vehicle type, the time lag is also a time according to the vehicle type.For example, the time required for transport from the point when the limit switch is turned on to the measurement site between the front door and the rear door is different for each vehicle type. Built in the computer. In the production line, intermediate finished products of multiple models will flow at random, but before being flowed to the production line, the car number etc. that will be flown on the line from now on based on production instructions etc. At the same time, by inputting to the computer at the tip of the line, the vehicle type flowing on the line can be specified to the computer that issues the measurement command. Therefore, the time lag corresponding to the vehicle type to be measured is automatically selected in the computer, and the measurement site is measured with the time lag corresponding to the vehicle type from the time when the limit switch is turned on.

  Note that there are a plurality of measurement sites in the longitudinal direction of the vehicle (for example, three locations between the fender and the front door, between the front door and the rear door, and between the rear door and the rear fender). Therefore, for each vehicle type, for example, the time lag from when the limit switch is turned on until the time between the fender and the front door reaches the measuring means, and then the time between the front door and the rear door reaches the measuring means. By measuring the time lag and then the time lag between the rear door and the rear fender until the measurement means is reached, it is possible to measure all the measurement parts in the longitudinal direction of the vehicle with a laser sensor. .

  In addition, at each measurement position in the longitudinal direction, there can be a plurality of measurement parts in the vertical direction. Therefore, the laser sensor positions that exist in the vertical direction described above are determined according to the position of the measurement part in the vertical direction of the vehicle. Thus, automatic measurement of all measurement parts in the longitudinal direction and the vertical direction of the vehicle can be realized. Since the vertical position of the laser sensor may differ depending on the vehicle type, for example, a plurality of laser sensors provided on the vertical member of the gate-type frame may be different depending on the vehicle type (or the scale of the vehicle). It can also be set as the structure which can be moved to a perpendicular direction. In addition, there are multiple types of laser sensors equipped with laser sensors at measurement levels according to vehicles that clearly differ in the vertical measurement site level depending on the size of the vehicle, such as a gate-type frame for general passenger car measurement and a gate-type frame for large trucks. A plurality of the portal frame can be positioned and fixed, and the portal frame (the laser sensor provided in the portal frame) can be selectively used according to the vehicle type or the scale of the vehicle.

  In a preferred embodiment of the assembling accuracy measuring system according to the present invention, the measuring means comprises a laser sensor, at least a plurality of the laser sensors are provided in the vertical direction, and the command means is a conveyance direction of the intermediate finished product. The limit switch is provided in the same number as the number of measurement parts in the longitudinal direction of the intermediate finished product, and the predetermined part of the intermediate finished product or the intermediate finished product is placed on the conveying means. The predetermined part of the mounting means that is turned on sequentially in accordance with the conveyance of the limit switch enables the timer-controlled measuring means to sequentially measure the measurement part corresponding to the limit switch that has been turned on. If there are multiple measurement parts, the multiple measurement parts can be measured simultaneously. To.

  The system of the present invention relates to an assembling accuracy measurement system having a configuration in which a limit switch is provided for each measurement region set in a longitudinal direction of a vehicle, that is, a conveyance direction by a conveyance means. This is because a limit switch is provided for each measurement site in the longitudinal direction of the vehicle when the assembly is not completed within a predetermined time at the parts assembly site or when the conveying means does not operate for a predetermined cycle time for some reason. Therefore, it is a great advantage to be able to flexibly cope with the temporary stoppage of the transport means. When there is only one limit switch, the measurement from the laser sensor is performed according to the time lag of the measurement part for each vehicle model built in the computer starting from the time when this limit switch is turned on. In an unforeseen situation in which the conveying means is stopped during the period, measurement at a predetermined measurement site cannot be performed. Since the limit switch is provided for each measurement part in the longitudinal direction of the vehicle, the measurement part corresponding to the limit switch is measured from the time when each limit switch is turned on. It is possible to realize highly accurate measurement of the measurement site according to the actual situation of the production line, such as an unexpected stop.

  When there are multiple measurement parts in the longitudinal direction of the vehicle, limit switches corresponding to each measurement part are provided in front of each measurement part, and the laser sensor is turned on before the first limit switch. A limit switch for turning off the laser sensor may be provided behind the last limit switch.

  Furthermore, in another embodiment of the assembly accuracy measurement system according to the present invention, each component assembly site of the production line includes the assembly accuracy of the components in the component assembly site, and the components preceding the component assembly site. Measurement results related to the assembly accuracy of parts at the assembly site are displayed, and if the measurement results are outside the allowable assembly tolerance, the information should be notified. It is characterized by.

  For example, each part assembly site is equipped with a monitor that displays the measurement site of the intermediate finished product. In the monitor, the parts have been assembled so far and the measurement between adjacent parts is completed. The result of the is displayed. As a matter of course, the assembly tolerances based on the design specifications are set for the gaps and steps between the parts, and among the measurement values of each measurement part displayed on the monitor, the measurement parts that are outside the set tolerance are Information reporting measures such as blinking in red, NG display, and alarming are being taken. When the worker recognizes such information in the middle of the production line, it can be reassembled in-line at that stage, or in some cases, such intermediate finished product can be taken out of the line and reassembled. it can. In this way, it is possible to correct the assembly of a vehicle with an unfavorable assembly quality at the earliest possible stage during assembly. As a result, the assembly of the separate parts is hindered, and therefore it is possible to completely avoid the troublesome work of correcting the assembly by assembling many parts.

  As can be understood from the above description, according to the assembly accuracy measurement system of the present invention, it is possible to realize highly accurate and quantitative measurement of measurement sites in all the vehicles assembled on the production line. By realizing this 100% measurement, it is possible to accumulate a large amount of quantitative data, and by feeding back the analysis results of the accumulated data to the subsequent assembly work, it is possible to build a production line that can achieve high assembly accuracy. Furthermore, it is possible to specify a part assembly site that should be centrally managed. Furthermore, according to the assembly accuracy measurement system of the present invention, automatic measurement of measurement parts of various vehicle types can be realized by a plurality of measurement means provided in the vertical direction and timer control that can be adjusted according to the vehicle type. . Furthermore, according to the assembly accuracy measuring system of the present invention, it is possible to identify a vehicle with an unfavorable assembly quality as early as possible and realize reassembly of the parts of the vehicle at an early stage. It is possible to eliminate troublesome work such as assembly and reassembly of parts.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing an embodiment of an assembly accuracy measuring system according to the present invention. FIG. 2 is a side view showing a measurement part, a limit switch, and a portal frame in an intermediate finished product of a vehicle. 3 is a view taken in the direction of arrows III-III in FIG. 2, and FIG. 4 is a view taken in the direction of arrows IV in FIG. 5A and 5B are schematic diagrams showing an embodiment of the monitor display, where FIG. 5A shows a case where the assembly determination is OK, and FIG. 5B shows a case where the assembly determination is NG. Yes. FIG. 6 is a schematic diagram showing an embodiment of a measurement management result in an arbitrary vehicle type.

  FIG. 1 is a schematic diagram showing an embodiment of an assembly accuracy measuring system of the present invention, and shows a part of a plurality of parts assembly sites constituting a production line 10. At each part assembly site, a conveyor 5 that conveys the intermediate finished product a of the vehicle, a portal frame 2 that is positioned and fixed so as to straddle the conveyor 5, and laser sensors 3a, 3b, and 3c installed on the portal frame 2 And limit switches 4b, 4c and 4d for instructing the computer 6 to start the timer control when measuring the measurement site of the intermediate finished product a with the laser sensor, and the laser on switch 4a for operating the laser sensor, A laser off switch 4e for stopping the operation of the laser sensor is provided, and the measurement system 1 is roughly constituted by these. In the illustrated embodiment, the limit switches 4b, 4c, and 4d are provided above the conveyor 5. However, when the conveyor is a slat conveyor that swivels underground from the ground with a certain extension. May have a configuration in which a limit switch is provided in the underground portion.

  Each component assembly site is provided with the measurement system 1 described above, and after the components are assembled at each component assembly site, gaps or steps between adjacent components are within the assembly tolerance. Whether or not it is contained can be confirmed on a monitor 23 attached to the horizontal member 22 of the gate-type frame 2 (the monitor display mode will be described later). If the measurement results for gaps and steps are outside the allowable tolerance for assembly, the worker can correct the assembly of the parts in-line or take down the intermediate finished product a from the conveyor 5 and take it offline. Correct the assembly of parts.

  The laser on switch 4a, limit switches 4b, 4c, 4d, laser off switch 4e, and laser sensors 3a, 3b, 3c are connected to the computer 6. As shown in the figure, the computer 6 is installed at each part assembly site, and the computers 6, 6,... Are connected to each other by RAN, and the computers 6 are installed at positions where the vehicles to be installed are mounted on the conveyor. A computer for inputting the vehicle number of the vehicle is also connected to each of the computers 6, 6,. The connection mode between the computers is arbitrary. For example, a mode in which a computer at each component assembly site is connected to one server computer can be applied. In accordance with the input vehicle number, the computer 6 in each part assembly site can sequentially specify the vehicle type flowing on the conveyor.

  In the computer, the required time from the time when each limit switch 4b, 4c, 4d is turned ON to each measurement type is input for each vehicle type, and the laser sensor is controlled by the timer based on the required time, Measure gaps and steps in the measurement area. The measurement results related to the gap and the level difference sensed by the laser sensor are transferred to the computer 6 and stored. In the embodiment shown in the drawing, for each part assembly site, first, the laser on switch 4a is turned on so that the laser sensors 3a, 3b, 3c attached to the gate-type frame 2 are in a sensing state, and are completed in the middle. The limit switches 4b, 4c and 4d for measuring each measurement part in the longitudinal direction of the product a are sequentially turned on to measure each measurement part based on the timer control, and finally the laser off switch 4e When turned off, the sensing of each of the laser sensors 3a, 3b, 3c is terminated.

  Here, although the time required from the time when each of the limit switches 4b, 4c, 4d is turned on for each vehicle type to the measurement site corresponding to each switch is different, the time required for each vehicle type is stored in the computer 6. Have been entered. In addition, information regarding the order of flowing vehicle types is transmitted and stored in the computer 6, and timer control data corresponding to each vehicle type to be measured can be selected to perform measurement according to the vehicle type. .

  FIG. 2 is a side view of one embodiment of the measurement site and limit switches 4b, 4c, 4d, and the portal frame 2 in the intermediate finished product a of the vehicle. In the illustrated embodiment, there are three measurement positions in the longitudinal direction of the intermediate finished product a (X, Y, Z in the figure), and each measurement position is set at each measurement position (X1, X2, and X2). Y1, Y2, Y3, Z1, Z2). Since the left and right sides of the intermediate finished product a are measured, a total of 14 measurement sites are set. The position and number of measurement parts can be variously selected depending on the vehicle type, scale, management accuracy, policy, and the like. In the case of providing a limit switch for each measurement position in the longitudinal direction, it is necessary to provide the same number of limit switches as the measurement position in the longitudinal direction. An embodiment in which only one limit switch is used and the required time to each measurement position is controlled by a timer may be used.

  The intermediate finished product a is placed on a plurality of scales b, b,... Installed on the conveyor 5, and the laser on switch 4a and limit switches 4b, 4c, 4d are attached to the scale b at the tip in the transport direction. The protrusion b1 for turning on is attached in a manner protruding sideways. Since the time required from the time when each limit switch is turned on is controlled by the timer with high accuracy, the placement mode of the intermediate finished product a on the scales b, b,... Needs to be positioned with high accuracy.

  3 is a plan view of FIG. 2 viewed from above, and FIG. 4 is a view of the intermediate finished product a viewed from the front. The intermediate finished product a flows in the X direction in FIG. 3, and the projection b1 pushes the laser-on switch 4a in the Y direction, so that each of the laser sensors 3a, 3b, 3c (see FIG. 2) can be sensed. The intermediate finished product a further flows, and the projection b1 pushes out the first limit switch 4b, so that the X position (first measurement position in the longitudinal direction) of the intermediate finished product a from that point is the laser sensor 3a, 3b, 3c. The time until crossing is controlled by a timer, the vicinity of the measurement part before and after crossing is sensed, and the measurement result of the gap and step of the required measurement part is sent to the computer 6. Thereafter, every time the projection b1 sequentially pushes the limit switches 4c and 4d, the measurement of the gap and the step between the measurement positions Y and Z is performed based on the timer control. In this way, since the limit switch is set for each of a plurality of measurement positions provided in the longitudinal direction of the intermediate finished product a, each time an emergency stop of the conveyor, which can occur frequently in the production line, is performed. There is no problem in measuring the measurement site at the measurement position.

  FIG. 5 shows an embodiment of a monitor screen attached to the gate-type frame 2 at an arbitrary parts assembly site. In FIG. 5a, the measurement results regarding all the gaps and steps of each of the seven measurement parts on the left and right side surfaces of the intermediate finished product a are within the assembly tolerance, and therefore the overall determination result is displayed as OK. Shows the monitor screen. In the production line, intermediate finished products that are sent to the painting process, for example, are completed by passing intermediate finished products through a plurality of parts assembly sites. Of course, since the degree of completion is different, the number and position of measurement parts are different for each part assembly site, and thus the number of measurement parts is different. FIG. 5b shows that one step (X) of the measurement part on the right side of the right and left sides is out of the assembly tolerance, the step result portion blinks, and the comprehensive judgment result is displayed as NG. Shows the monitor screen. In addition, there is a method of making the worker recognize it reliably by taking measures such as issuing an alarm.

  Each component assembly site is provided with a monitor 23 shown in FIG. 5. The monitor 23 is connected to the computer 6, and whether or not the measurement results regarding the gap and the step are within an allowable tolerance in the computer. The determination result is displayed on the monitor 23. When the assembly of the parts at an arbitrary part assembly site is completed and the intermediate finished product a has completely passed through the gate-type frame 2, the determination results of the assembly accuracy of all measurement parts at the component assembly site are obtained. If it can be displayed on the monitor and the overall judgment is NG, the parts are reassembled at the parts assembly site if possible, and the intermediate finished product is already in the next parts assembly site due to the operation of the conveyor. In the case of being conveyed, the parts can be reassembled at the previous part assembly place at the next part assembly place.

  In this way, the assembly accuracy can be confirmed immediately after the parts are assembled, and the intermediate finished product that is not accurate can be corrected at that point, so the intermediate finished product has approached the finished vehicle. Assembly correction at the stage (a stage where it is difficult to assemble and reassemble parts) can be completely avoided. In addition, since the assembly accuracy of all vehicles produced on the production line can be checked, it is possible to completely avoid the problem that intermediate finished products with assembly failures are sent to subsequent processes such as painting lines. Can do.

  FIG. 6 is a schematic diagram showing an embodiment of a measurement management result in an arbitrary vehicle type, and shows a result related to a gap and a step in two places out of seven measurement parts, for example. Such a result is displayed on the computer screen based on the measurement data stored in the computer. Assembling allowable tolerances (standards) are set for the gap and the step, and for example, measurement results are output in time series for each vehicle type as shown in the figure. In the illustrated embodiment, the positive and negative assembly tolerances are set to 1.5 mm (standard value is 3 mm), and the intermediate finished products of all the car numbers within the gap / step are within the assembly tolerance in the measurement part Y1. In the measurement part Y3, it is shown that the four units do not satisfy the assembly tolerance for the step. In addition to the time series graph of the measurement results, the maximum / minimum value and average value of the measurement values, the process capability index (Cp value), the 3σ value, and the like are displayed on the screen.

  Based on these data, it is possible to identify a part assembly site with poor assembly accuracy, and to improve the assembly accuracy of the entire production line by executing centralized management of the part assembly site. it can. In addition, based on the data, it is possible to analyze the median value of measurement values and the tendency of variation, and feed back the analysis results to subsequent production, thereby building a production line with high component assembly accuracy. It becomes possible.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and there are design changes and the like without departing from the gist of the present invention. They are also included in the present invention.

The schematic diagram which showed one Embodiment of the assembly | attachment precision measurement system of this invention. The side view which showed the measurement site | part, limit switch, and portal frame in the intermediate finished product of a vehicle. The III-III arrow line view of FIG. The IV arrow line view of FIG. 4A and 4B are schematic diagrams illustrating an embodiment of a monitor display, in which FIG. 5A illustrates a case where the assembly determination is OK, and FIG. 5B illustrates a case where the assembly determination is NG. The schematic diagram which showed one Embodiment of the measurement management result in arbitrary vehicle types.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Measurement system, 2 ... Gate frame, 21 ... Vertical member, 22 ... Horizontal member, 23 ... Monitor 3a, 3b, 3c ... Laser sensor, 4a ... Laser on switch, 4b, 4c, 4d ... Limit switch, 4e ... Laser off switch, 5 ... conveyor, 6 ... computer, 10 ... production line, a ... intermediate finished product, a1, a2 ... parts, b ... scale, b1 ... projection

Claims (3)

An assembly accuracy measurement system for measuring assembly accuracy between adjacent components in a plurality of assembly components constituting an intermediate finished product of a vehicle,
A plurality of laser sensors that are positioned and fixed at predetermined positions on the production line and that measure gaps and / or steps at measurement sites between the adjacent parts; a conveying means that conveys the intermediate finished product at a predetermined speed; and Command means for outputting a measurement command to the laser sensor, and
A plurality of the laser sensors are provided in the vertical direction, and the command means includes a limit switch provided in the conveyance direction of the intermediate finished product, and the limit switch is the same as the number of measurement parts in the longitudinal direction of the intermediate finished product. Provided,
When the predetermined part of the intermediate finished product or the predetermined part of the mounting means for placing the intermediate finished product on the transporting means sequentially turns on the limit switch according to the transport, the measurement command from the limit switch is sent to the laser sensor. The laser sensor sent and controlled by the timer sequentially measures the gap and / or step of the measurement part corresponding to the limit switch that is turned on, based on the conveyance speed of the conveyance means and the position of the measurement part. An assembly accuracy measurement system characterized in that, when there are a plurality of measurement parts on the vertical line, the plurality of measurement parts can be measured simultaneously . The assembly accuracy measurement system further includes storage means for storing the position of the measurement part, and the laser sensor performs measurement based on the transport speed of the transport means and the position of the measurement part in the storage means. The assembly accuracy measuring system according to claim 1 , wherein a gap and / or a step of the part is measured. At each part assembly site on the production line, the measurement results regarding the assembly accuracy of the parts at the component assembly site and the assembly accuracy of the parts at the part assembly site prior to the parts assembly site are displayed. 3. The assembly accuracy measuring system according to claim 1, wherein when the measurement result deviates from the assembly tolerance, the information can be notified. 4. .

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