JPH02219700A - Automatic focusing of reading sensor for automatic drawing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic focusing method for a mark reading sensor in an automatic drafting machine.

[Conventional technology]

When drawing continuously in a certain range of a long piece of paper, when the drawing of a certain range of paper is completed, a connecting mark is drawn on the paper with the drawing head so that the drawing part of each range is continuous. When drawing in the next range, a mark reading sensor disposed on one drawing head reads the connecting marks, and drawing in the next range is performed using the position data of the connecting marks as a reference.

Further, a coordinate reference mark printed in advance on a sheet of paper is read by a mark reading sensor provided in a drawing head, and drawing is performed using this mark position as an X-Y reference.

As the mark reading sensor, a light reflection type photosensor is used and is attached to the substrate of the drawing head.

(Problems to be Solved by the Invention) As described above, when the mark reading sensor is attached to the substrate of the drawing head, it is necessary to change the focus of the mark reading sensor depending on the thickness of the paper.

Conventionally, the adjustment was done manually, but there was a drawback that the operation was not easy. If an automatic focus device is incorporated into the mark reading sensor, the above-mentioned defects can be solved, but the mechanism becomes larger and the weight of the drawing head increases, making it impossible to perform high-speed # control of the drawing head.

An object of the present invention is to enable the focus of a mark reading sensor to be automatically set on a sheet of paper without incorporating an automatic focus device into the mark reading sensor.

[Means to solve problems]

In order to achieve the above object, the present invention provides an actuator controlled by a processor on the substrate of a drawing head whose movement is controlled in XY force directions relative to the paper on the paper support surface, and an actuator controlled by a processor is provided on the output side of the actuator. a writing instrument holder is attached to the paper, the actuator is driven to control the writing instrument holder in a direction toward and away from the paper along an axis substantially perpendicular to the paper, and the writing instrument holder is held on the paper. In an automatic drawing machine, the mark reading sensor is attached to a member interlocking with the writing instrument holder. Before mounting and reading the mark on the paper by the mark reading sensor, drive the actuator to move the mark reading sensor up and/or down with respect to the paper, and at this time change the amount of light of the mark reading sensor and the writing instrument holder. The position signal of the writing instrument holder at the time of maximum light intensity of the reading sensor is detected from the position signal of the reading sensor, and based on this position signal, the writing instrument holder is set at a position corresponding to the position signal when reading the mark. It is something.

〔Example〕

The structure of the present invention will be described in detail below with reference to embodiments shown in the accompanying drawings.

2 is supported movably on the drawing board 4 in the direction of the X coordinate axis.
A Y cursor (not shown) is movably connected to the rail, and a drawing head 6 is connected to the Y cursor. A plurality of writing instruments 12 are removably held in a writing instrument stocker 10 provided in a main body 8 of the automatic drafting machine. A guide shaft 18.2 is provided on the base plate 14 of the head 6.
0 is erected, and an elevating member 16 is supported along the guide shafts 18 and 20 so as to be freely movable. A writing instrument holder 22 equipped with a moving arm 21 is provided on one side of the elevating member 16 . A moving coil 26 is fixed to a coil holder 24 attached to the elevating member 16,
The moving coil 26 faces a field component 28 fixed to the substrate 14. When the moving coil 26 is in a non-energized state, the lifting member 16 is configured to rise due to the elastic force of the return spring 3o until its upper end is stopped by an upper limit stopper 32 fixed to the base plate 14. There is. The field component 28 and the moving coil 26 constitute an actuator 32, and the coil holder 24 constitutes an output shaft of the actuator 32.

34 is a known position sensor, which includes a light source 36 and a light receiving element 3.
8 and a shielding plate 40, the shielding plate 40 is fixed to the elevating member 16, and the other components are fixed to the substrate 14.

A sensor holder is fixed to the other side of the elevating member 16, and a known mark reading sensor 42 is attached to this.

The mark reading sensor 42 uses a sensor module that combines a reflective photosensor and a lens.

On one side of the drawing board 4, there is a known roll paper feeding section 4.
4 is provided, and a roll paper winding section 46 is provided on the other side.

The Y rail 2 is controlled by a processor 48.

When the X motor (not shown) is driven, the Y cursor moves in parallel along the drawing board 4 in the direction of the X coordinate axis, and when the Y motor (not shown) is driven, the Y cursor moves along the Y rail 2. is configured to do so.

The moving coil 26 is connected to the up/down driver 5
The position sensor 34 and the mark reading sensor 42 are connected to the processor 48 via an amplifier 54,56 and an analog/digital converter 58.

The automatic drawing machine shown in this embodiment is configured so that writing instruments 12 can be exchanged automatically between the writing instrument holder 22 of one drawing head 6 and the writing instrument stocker 10 of the main body 8. . In carrying out the present invention, a paper-driven automatic drafting machine can be used in addition to the flatbed type automatic drafting machine as described above.

In the above configuration, when drawing one drawing, a roll of paper is laid out on the drawing board 4, and the drawing head 6 performs one drawing on this roll paper. When the drawing of a certain range of the roll paper 60 on the surface is completed, a connecting mark is drawn at a predetermined position on the roll paper 60.Next, the drive device of the roll paper winding section 46 is driven under the control of the processor, and a certain amount of paper is drawn on the roll paper 60. A new roll of paper is taken up by the roll winding section 46, and a new roll of paper is unwound onto the drawing board 4.

When the drawing head 6 starts drawing the next drawing, it first reads the connecting mark with the mark reading sensor 42 and draws the next drawing based on the position of the connecting mark 42. In this way, one drawing head In No. 6, a so-called connecting drawing that is continuous with the previous drawing can be performed on a long roll paper by using the position of the connecting mark as a drawing reference.

Next, automatic focusing of the mark reading sensor 42 will be explained with reference to the flowchart in FIG. When performing this operation, the writing instrument held by the writing instrument holder 22 of the drawing head 6 is returned to the writing instrument stocker 10, and the roll paper is spread out on the drawing board 4.The automatic focusing operation is started. Then, the processor 48 controls the current of the moving coil 26 to lower the elevating member 16, thereby lowering the holder 22 to the bottom dead center above the paper. Then, slowly raise it to top dead center (block 1). When the lifting member 16 is raised, the processor 48 monitors or stores the digital amount of the output photocurrent of the mark reading sensor 42 in correspondence with the digital value of the output of the position sensor 34 (block 2). The output photocurrent is at a maximum at the point of maximum sensitivity during the transition of sensor 42 from the down position to the up position, as shown in FIG.

Next, the processor 48 detects the maximum light amount of the mark reading sensor 42 and sets the position of the writing instrument holder 22 at 1.
Memory based on the output digital value of the position sensor 34 (
Block 3) 0 Next, the lifting member 16 is slowly lowered to the bottom dead center (block 4).
The processor 48 monitors the light amount of the mark reading sensor 42 (block 5). Next, the processor 48 monitors the light amount of the mark reading sensor 42.
The maximum light amount is detected when the writing instrument holder 22 is lowered, and the position of the writing instrument holder 22 corresponding to this maximum light amount is memorized (block 6).
)0 Next, the processor 48 determines whether the operation of detecting the maximum light amount has been performed a predetermined number of times (three times in this embodiment) (block 7), and if Yes, the process corresponds to each of the maximum values of the light amount. Calculate the average value of the position of the writing instrument holder 22 (block 8), use this average value as the focal length matching position where the mark reading sensor 42 has maximum sensitivity with respect to the paper 60 side, and read the joint marks by the mark reading sensor 42. During,
The height position of the writing instrument holder 22 with respect to the paper support surface is maintained at the above average value (block 9).

〔effect〕

As described above, the present invention can automatically focus the mark reading sensor on the paper surface by using the up-down drive mechanism of the writing instrument, and there is no need to provide the mark reading sensor with a drive mechanism for an automatic focusing device. There is this effect.

[Brief explanation of the drawing]

Figure 1 is a sectional view, Figure 2 is a plan view, Figure 3 is an explanatory diagram, Figure 4 is an explanatory diagram, Figure 5 is an explanatory diagram, Figure 6 is a block diagram, and Figure 7 is a flowchart. be. 2... Y rail, 4... Drawing board, 6... Drawing head, 8... Main body, 10... Writing instrument stocker 12.
...Writing instrument, 14...Substrate, 16...Elevating member, 1
8.20... Guide shaft, 21... Moving arm, 22
...Writing instrument holder. 24...Coil holder, 26...Moving coil. 28... Field component, 30... Return spring, 32...
・Actuator, 34...Position sensor, 36...
Light source, 38... Light receiving element, 40... Shielding plate, 42...
. . . Mark reading sensor, 44 . . . Roll paper feeding section, 46 . . . Roll paper winding section, 60 . . . Paper.

Claims (1)

[Claims] (1) An actuator controlled by a processor is provided on the substrate of the drawing head that is controlled to move in the XY directions relative to the paper on the paper support surface, a writing instrument holder is attached to the output side of the actuator, and the actuator to control the writing instrument holder in a direction toward and away from the paper along an axis substantially perpendicular to the paper, and draw a predetermined drawing on the paper using the writing instrument held by the writing instrument holder. Also, in an automatic drawing machine configured to read marks on the paper with a reflective mark reading sensor provided on the drawing head, the mark reading sensor is attached to a member interlocking with the writing instrument holder,
Before the mark reading sensor reads the mark on the paper, the actuator is driven to move the mark reading sensor up and/or down with respect to the paper, and at this time, the change in the amount of light of the mark reading sensor and the position of the writing instrument holder are determined. From the signal, the position signal of the writing instrument holder at the maximum light intensity of the reading sensor is detected, and based on this position signal,
An automatic focusing method for a mark reading sensor, characterized in that, when reading a mark, the writing instrument holder is set at a position corresponding to the position signal.