JP2509595Y2 - Table type measuring device - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an original plate for making a printed wiring board and a table type length measuring device used to measure the size and coordinate position of a figure such as a printed matter requiring high accuracy. .

[0002]

2. Description of the Related Art Conventionally, as such a table type length measuring device, for example, a fluorescent lamp is arranged below a transparent plate of a measuring table to illuminate an original plate with the fluorescent lamp, and above the table. Is provided with a moving means for moving the microscope in an XY plane parallel to the table, and the microscope is moved to visually check the measured point in the figure of the original plate, and the X coordinate of the measured point. Also, there is a device in which the required dimension is measured by reading the Y coordinate with a reading device associated with the moving means.

Further, in order to avoid a length measurement error due to the parallax of the microscope in the above-mentioned device, an image pickup means such as a television camera is provided in place of the microscope, and the image of the required position of the object to be measured is picked up by the image pickup means. Has also been put into practical use, which is configured so that the measured point is enlarged and displayed on a monitor TV, and the point to be measured is visually recognized through the monitor TV.

An example of a table type length measuring device using this monitor television is shown in FIGS. 6 and 7.

In the figure, the table type length measuring device has a translucent measurement table 31 on which an object to be measured W is placed, and a large number of fluorescent lamps 32a on which the object to be measured W placed on the measuring table 31 is arranged from below. Lighting device 32 that illuminates with the measurement table 3
1, a television camera 33 that is movable in the X-Y directions and that observes the object to be measured W from above,
An arithmetic unit 34 based on the XY movement amount of the television camera 33.
Is configured to measure the required portion of the object to be measured W.

In these figures, the lighting device 32
Is a fluorescent lamp 32a and a power supply device 3 for supplying power to the fluorescent lamp 32a.
2b, and the image obtained by the TV camera 33 is enlarged and displayed on the monitor TV 35.

Reference numeral 36 denotes a pedestal erected on the measurement table 31 so as to be movable in the Y direction, and the television camera 33 is mounted on a traveling base 37 movably mounted on the pedestal 36 for movement in the X direction. It is attached. A drive handle 38 is provided on the front surface of the device for moving the gantry 36 and the traveling platform 37 in the XY directions via drive transmission means (not shown).

[0008]

However, in the above-mentioned table type length measuring device, since the object to be measured on the measuring table is illuminated from below by a plurality of fluorescent lamps 32a, it has the following drawbacks. It was

That is, when the object W to be measured is made of a thermoplastic material such as a film original plate, the heat generation of a large number of fluorescent lamps causes the thermoplastic material to curl or expand and contract, thus lowering the measurement accuracy. In particular, when the object to be measured is a circuit pattern on a printed wiring board, it is necessary to capture an image at a high magnification, high illuminance is required, and heat generation becomes large.

Since the fluorescent lamps 32a are arranged at a predetermined interval, it is inevitable that the illuminance distribution becomes uneven on the measurement table 31 due to the arrangement of the fluorescent lamps. In order to prevent the unevenness of the illuminance distribution, a light diffusing plate or the like is usually used, but it is difficult to obtain a completely uniform illuminance distribution.

Since such unevenness of the illuminance distribution affects the density of the image lines stored in the film original plate, when processing a high magnification magnified image by the observation optical system, the edge identification function of the image lines is used. This will affect the accuracy and reduce the autofocus accuracy and the length measurement accuracy.

In order to solve the problems of heat generation of the light source and unevenness of illuminance distribution, an EL plate (electro luminescent lamp) may be used. However, this does not cause any inconvenience when the measurer visually observes the entire object to be measured, but the EL plate emits a small amount of light, so when processing a signal of a high-magnification image, light becomes insufficient. In addition, in the case of the table type length measuring device using the monitor TV 34 as described above, flicker occurs in the image on the monitor TV 33, or a black band-shaped pattern (hereinafter referred to as a band-shaped pattern) is generated. appear.

The cause of these occurrences is the fluorescent lamp 32a.
This is because the blinking frequency of and the vertical scanning frequency of the monitor television 34 (hereinafter referred to as the field frequency) are not synchronized. That is, in a normal television, a power supply asynchronous system in which the field frequency and the power supply frequency are not synchronized is standard. However, since the fluorescent lamp blinks at this power supply frequency, the field frequency of the monitor TV 34 is changed. The difference from the blinking cycle of the screen due to appears on the screen as a deviation of synchronization.

Therefore, the screen of the monitor television 34 is very difficult to see, which not only causes great operator fatigue, but also causes erroneous measurement.

The present invention solves the above problems,
An object of the present invention is to provide a table-type length measuring device equipped with a lighting device that has a simple structure, does not cause deformation of an object to be measured due to heat generation, has no uneven illuminance distribution, and does not cause flickering or a band-shaped pattern on a TV monitor at all. To do.

[0016]

In order to achieve the above object, a table type length measuring apparatus according to the present invention is provided with a translucent plate on which an object to be measured is placed and an illumination disposed below the translucent plate. A measurement table equipped with a device, an observation means for observing the object to be measured from above, and the observation means are mounted,
A table provided with a moving means for relatively moving the object to be measured and the observing means in an XY plane parallel to the transparent plate, and measuring the object to be measured by the amount of movement of the observing means. In the mold length measuring device, a filament light source device installed outside the range of the light transmitting plate, a light guide for guiding the light of the light source below the light transmitting plate, and a light guide provided on the terminal side of the light guide. A light projecting unit that irradiates the light plate from below, and a light projecting unit that is disposed below the light transmitting plate and moves following the movement of the observation means in the Y direction, and also moves the light projecting unit in the X direction. A guide means for holding the loop member, and a loop group provided in the X direction and at least one loop of which is formed by mutually engaging a plurality of loops formed so as to surround the transparent plate above and below. , With the light projecting unit through the loop group The serial observation means mechanically coupled, both are characterized by being adapted to move synchronously.

[0017]

Since the filament light source is adopted, the flicker of the screen of the monitor TV caused by the blinking cycle of the conventional fluorescent lamp and the band-shaped pattern are eliminated, and the light source is provided outside the range of the light-transmitting plate and is transmitted by the light guide. Since the light is guided downward to the light plate, the object to be measured is not affected by the heat generated by the light source.

Further, the light projecting portion provided at the end of the light guide is guided in the X direction by the guide means which moves in the Y direction following the movement of the observing means, and engages a plurality of loops. Since it is configured to move in the same direction as the observation means by the loop group, the light projecting unit can move in perfect synchronization with the movement of the observation means, and the observation area by the observation means is always kept. Irradiation can be performed and the observation area can always be illuminated with a uniform illuminance distribution by a single light source.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a table type length measuring device according to the present invention will be described in detail below with reference to the drawings, but it goes without saying that the technical scope of the present invention is not limited thereto. is there.

FIG. 5 conceptually shows a main part of the table type length measuring device according to the present invention.

An observing means 2 is arranged above the transparent plate 1 made of glass or the like, and the observing means 2 is moved in the X direction by an observing means moving loop 3.

On the other hand, a light projecting portion 4 having a reflecting mirror 4a is arranged at a position below the light transmitting plate and facing the observing means 2. The light projecting section 4 is connected to a filament light source section 6 containing an incandescent bulb through a light guide composed of an optical fiber 5 and irradiates the observation area of the translucent plate 1 with light as indicated by an arrow A.

As shown in the figure, since the filament light source section 6 is provided outside the observable range of the observing means 2, that is, outside the observing range of the transparent plate 1, its heat is generated.
It does not affect the object to be measured placed on it, and a strong light source can be used with confidence.

The light projecting portion 4 is connected to a lower portion of a light projecting portion driving loop 7 which forms a loop so as to surround the light transmitting plate 1, and an upper portion of the light projecting portion driving loop 7 is It is connected to the lower side of the observation means drive loop 3 by an engaging metal fitting 8.

Therefore, when the observing means 2 moves in the direction of arrow B, the upper part of the light projecting section drive loop 7 which is engaged with the lower part of the observing head moving loop 3 by the engaging metal fitting 8 moves in the direction of arrow C. As a result, the light projecting unit 4 moves in the same direction as the arrow B and by the same distance, and the movement in the X direction can be completely synchronized with the movement of the observation means.

On the other hand, the observation means 2 comprises an X-direction drive base 13
It is mounted on (FIG. 1) and is moved in the Y direction together with the X-direction drive gantry. As will be described later, the light projecting section drive loop 7 is also held and moved by the X-direction drive gantry. Therefore, the movement in the Y direction can be perfectly synchronized.

Although only two loops are provided in FIG. 5, three or more loops may be provided depending on the configuration of the device and design, and these may be engaged with each other to obtain the same result. Obtainable.

FIG. 1 shows a rear view of the measuring table section in the embodiment of the table type length measuring device according to the present invention.

For convenience of explanation, the measurement table body 10 and the transparent plate 21 are shown in cross section.

An X-direction drive base 13 is placed on the measurement table main body 10 via guide rails 11 and wheels 12, and an observation means is held on the top of the X-direction drive base 13. The observation head 14 is mounted so as to be movable in the X direction.

At the lower part of the observation head 14, an engaging projection 14 is formed.
a is provided, and the guide groove 13 on the upper part of the X-direction drive base 13 is provided.
It is slidable and fitted in a without gap.

The observation head 14 is connected to an observation head drive loop 15 by an engagement fitting 14b. The observation head drive loop 15 includes pulleys 15a, 15b, and
15 c and 15 d, and a drive pulley 16 a attached to the rotation shaft of the drive motor 16 are formed by hanging a metal wire, and the observation head 14 is rotated by driving the drive motor 16 by a drive control device (not shown). Can be moved in the X direction.

Below the observation head drive loop 15, pulleys 17a, 17b, 17c, 17d, 17e,
17 f, 17 g, 17 h, 17 i, 17 j is provided with a light projecting section drive loop 17 formed by hooking a metal wire. It is coupled to the lower portion of the light source 15, and is engaged with the light projecting portion 19 at the lower portion thereof.

At the lower part of the X-direction drive base 13, the light projecting section 1 is provided.
2 as guide means for holding 9 slidably in the X direction
The guide rod 20 of the book is the guide rod holding metal fitting 20a (FIG. 2).
The transparent plate 21 such as a glass plate is supported between the guide bar 20 and the X-direction drive frame 13 by the support 21a in parallel with the upper surface of the measurement table body 10. ing.

Reference numeral 10a designates the X-direction drive base 13 as Y.
It is a pulley to which a Y-direction drive loop is applied for driving in the direction, and the Y-direction drive loop is rotationally driven by a drive motor (not shown).

FIG. 2 shows a view of the X-direction drive base 13 and the light projecting portion 19 as seen from the left side of FIG.

The light projecting portion drive loop 17 is turned forward by a pulley 17c, turned downward by a pulley 17b, and further driven by a pulley 17d so as to traverse below the light transmitting plate 21 (see FIG. 1). ) Direction, the pulleys 17h, 17i, 17j
A similar wire hook is also formed by the combination of.

On the front surface of the observation head 14, a mounting base 22 is provided.
A television camera 22 as an observing means is attached via a, and the position of the television camera 22 can be adjusted by moving the adjusting knob 22b in the vertical direction.

The image pickup lens 22 of the television camera 22
The focus of c is automatically adjusted by a known autofocus technique.

Inside the light projecting section 19, a reflecting mirror 19a is arranged at a predetermined angle so that the light incident from the optical fiber 23 is reflected toward the image pickup lens 22c of the television camera 22.

The light projecting portion 19 is attached to the pointing member 1 by the metal fitting 19b.
The two guide rods 20 which are fixed to 9c and which are horizontally held in the X direction by the guide rod holding metal fittings 20a which are hung and supported from the X-direction drive base 13 are the support members 19c.
Penetrates through. The light projecting portion 19 is engaged with the light projecting portion driving loop 17, and can freely move in the X direction following the loop.

The optical fiber 23 is held by a cable bear 24. The cable carrier 24 is formed by rotatably connecting a plurality of box-shaped metal fittings 24a with bolts 24b. The cable carrier 24 can be freely bent in a horizontal plane, but has rigidity in the vertical direction. Even if the part 19 moves, the optical fiber 23 can smoothly follow the light projecting part 19 without contacting the measurement table body 10 below.

FIG. 3 is a schematic diagram showing how the cable bear 24 follows.

In practice, it is difficult to keep the long distance to the filament light source 25 completely horizontal with only the cable bear 24. Therefore, it is connected to the swing arm 26 pivotally supported by the rotary shaft 26a on the way. , Cable carrier 24
The optical fiber 23 is held horizontally by both the and the swing arm 26.

In the figure, when the light projecting portion 19 is at the position P, the swing lever 26 swings to move the cable carrier 2
When the Q position is reached, the motion of the light projecting portion 19 can be smoothly followed by simply returning to the original position and bending the cable bear 24.

An incandescent bulb and a lens are built in the filament light source 25, and the light of the incandescent bulb is collected by the lens to be a parallel light beam and sent to the optical fiber 23. The incandescent bulb is hardly affected by the power supply frequency and has no flicker, so that the screen of the monitor TV does not have a flicker or a band-like pattern unlike the conventional fluorescent lamp.

Further, since the filament light source 25 is installed outside the observation range of the translucent plate 21, the heat generated by the incandescent bulb does not adversely affect the object W to be measured. Therefore, it is possible to use a filament bulb having a larger wattage, and it is possible to secure a sufficient amount of light in the observation region. Further, by attaching a filter to the light source, it is possible to enhance the heat absorption effect and to add coloring.

FIG. 4 shows a perspective view of the whole of this embodiment.

The measuring table body 10 has a built-in arithmetic unit for measuring the distance, and while operating the switch section 27 on the front side, the observation head 14 equipped with the television camera 22 is moved in the X direction. In addition, the TV camera 22 is moved to a predetermined position by driving the X-direction drive base 13 in the Y direction.

A light projecting portion 19 (not shown in FIG. 4), which always moves in synchronization with the movement of the television camera 22 as described above, is arranged under the light transmitting plate 21. The observation area of the object to be measured W, such as the original film of the printed wiring board placed on 21, is illuminated by the filament light source with no flicker or unevenness and with sufficient brightness.

The image picked up by the television camera 22 is enlarged and displayed on the screen of the monitor television 28 so that the operator can easily observe it.

A cross mark 28a is displayed on the screen of the monitor TV 28, for example, and the operator aligns the intersection 28b with the start point of the portion of the object W to be measured and gives an instruction to start the measurement. Then, the television camera 22 is finely driven, and the intersection point 28b is aligned with the end point of the portion where the length measurement is desired, and an instruction to end the length measurement is issued. X of observation head 14
The amount of movement in the direction and the amount of movement in the Y direction of the X-direction drive base 13 are detected by a position detector (not shown), and based on this, the arithmetic unit built in the measurement table body automatically detects the length. Calculate the length of the part up to μ unit,
The length measurement result is displayed on the screen of the monitor television 28.

In this embodiment, only the light projecting portion 19 is provided as the illuminating device below the light transmitting plate 21, but the light projecting portion 19 is provided so that the operator can easily operate it while looking at the whole plate W to be measured. A plurality of fluorescent lamps may be arranged in parallel below the portion 19 as in the conventional case.

In this case, it is not necessary to increase the number of the fluorescent lamps as compared with the conventional one, but the blinking frequency of the fluorescent lamps is changed by improving the power supply device of the fluorescent lamps and the monitor television 27.
It is desirable to synchronize with the field frequency of 1 to avoid band patterns.

The cable bear 24 for horizontally holding the optical fiber 23 is not limited to the structure in which the box-shaped metal fitting 24a is coupled with the bolt 24b as shown in FIG. Anything can be used as long as it can be bent freely and can hold the optical cable horizontally.

Further, in the present embodiment, the image pickup device comprising the television camera 22 and the monitor television 27 is adopted as the observing means. However, the lens 22c of the television camera 22 is provided with an eyepiece so that the operator can directly see it. May be.

In some cases, another intermediate loop may be interposed between the observation head drive loop 15 and the light projecting unit drive loop 17, and the pulleys that form these loops must be arranged. It can be changed as appropriate. Furthermore, it is possible to provide a tension pulley in the middle of each drive loop as necessary to prevent the loop from idling.

Further, in this embodiment, the observation head 14 is
Although it was driven in the X direction by the observation head drive loop 15, the observation head drive loop 15 may be a dedicated loop for moving the light projecting unit 19 by separately providing X direction drive means.

[0059]

[Effect of the Invention] The table type length measuring device according to the present invention is
Since it is configured as described above, the filament light source
The flicker of the screen of the monitor TV caused by the blinking cycle of the conventional fluorescent lamp and the band-shaped pattern are eliminated, and since the light source is provided outside the range of the light-transmitting plate and guided by the light guide below the light-transmitting plate, The measured object is no longer affected by the heat generated by the light source. This makes it possible to use a stronger light source and secure a sufficient amount of light.

Further, the light projecting portion provided at the end of the light guide is guided in the X direction by the guide means which moves in the Y direction following the movement of the observing means, and the observing means is provided by the interposition of a plurality of loops. Since it is formed so as to be linked in the same direction as, the light projecting section can move in perfect synchronization with the movement of the observing means, and the observation area of the observing means is always bright enough. Can be irradiated.

Moreover, since the light emitted from the light projecting portion is the light from a single light source, there is no unevenness in the illuminance distribution and the operator is tired and there is no risk of erroneous measurement.

Further, since the synchronous movement of the light projecting portion can be easily realized by connecting a plurality of loops and interlocking with the observation means, no separate drive means or control device for the synchronous movement is required. Therefore, it is possible to provide a table type length measuring device that is extremely inexpensive and has excellent operability.

[Brief description of drawings]

FIG. 1 is a rear view of a measuring table section of a table-type length measuring device according to an embodiment of the present invention.

FIG. 2 is a side view of the measurement table section in FIG.

FIG. 3 is a schematic diagram showing a state in which a cable bear follows a light projecting unit and moves.

FIG. 4 is a perspective view showing an entire table-type length measuring device according to an embodiment of the present invention.

FIG. 5 is a view conceptually showing a main part of a table-type length measuring device according to the present invention.

FIG. 6 is a schematic diagram showing a configuration of a conventional table-type length measuring device.

FIG. 7 is an overall perspective view of a conventional table-type length measuring device.

[Explanation of symbols]

 10 Measurement Table Main Body 13 X-Direction Drive Stand 14 Observation Head 15 Observation Head Drive Loop 16 X-Direction Drive Motor 17 Projector Drive Loop 18 Engagement Metal Fitting 19 Projector 19a Reflector 20 Guide Rod 21 Translucent Plate 22 Television Camera 23 Optical fiber 25 Filament light source 26 Swing lever 28 TV monitor

Claims (1)

(57) [Scope of utility model registration request] 1. A measurement table comprising a translucent plate on which an object to be measured is placed and an illuminating device arranged below the translucent plate, and an observation means for observing the object to be measured from above.
The observing unit is mounted, and the displacing unit includes a moving unit that relatively moves the object to be measured and the observing unit in an XY plane parallel to the translucent plate, and the object to be measured depends on a moving amount of the observing unit. A table-type length measuring device for length measurement, comprising: a filament light source device installed outside an observation range of the translucent plate; a light guide for guiding light from the light source below the translucent plate; A light projecting unit which is provided on the terminal end side of the guide and irradiates the light transmitting plate with light from below; and a light projecting unit which is arranged below the light transmitting plate and moves following the movement of the observation means in the Y direction. A guide means for holding the light projecting portion so as to be movable in the X direction, and a plurality of loops provided in the X direction, at least one of which is formed so as to surround the upper and lower sides of the translucent plate, are engaged with each other. And a loop group Through the loop group mechanically coupled to the observation unit and the light projecting unit, the table type length measuring device, characterized in that both are to move synchronously.