JPS61235194A - Method of detecting breaking of lead 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 [Industrial Field of Application] The present invention is characterized in that one of a plurality of lead cartridges is selected and placed directly under a push pin of a head, and the push pin is used to push the lead in the lead cartridge. The present invention relates to a method for detecting lead breakage in a lead cartridge in an automatic drawing machine that draws lines by applying pressure to the lead cartridge.

[Conventional technology]

In this type of automatic drafting machine, the remaining length of the lead in the lead cartridge is memorized as the amount of upward movement of the push pin, and the push pin is lowered at high speed to near the already memorized travel distance to attach the lead in the lead cartridge. Those with a structure that allows pressure contact.

It is disclosed in Japanese Patent Publication No. 57-55080. The above device is configured such that when the push pin descends to a predetermined position and the amount of lead remaining in the lead cartridge decreases, a limit switch operates to detect lead breakage.

[Problem that the invention seeks to solve]

As mentioned above, when detecting lead breakage in a lead cartridge using a single adhesive switch, if a lead cartridge with a relatively small amount of lead remaining is selected and used, the lead will run out in a short time and the drawing The number of times the core breaks inside increases.

Therefore, the present invention provides two states of broken lead in the lead cartridge, and when detecting the amount of remaining lead, determines whether the lead is broken when the amount of remaining lead is relatively large, and during drawing, when the amount of remaining lead is relatively small. The defect is removed by detecting the core breakage in a state where the core is not clean.

[Means to solve problems]

The present invention uses a lead cartridge in an automatic drafting machine that selects one of a plurality of lead cartridges and places it directly under a push pin of a head, and presses the lead in the lead cartridge with the push pin to draw a drawing line. The state of lead breakage is set to two stages: a first state with a relatively small amount of lead remaining and a second state with a relatively large amount of lead remaining, and the amount of lead remaining in the lead cartridge is determined by the amount of movement of the push pin. If the amount of lead remaining in the lead cartridge is detected by the above-mentioned second state, the lead cartridge in the broken state is not used, and 1.
During drawing, the broken lead state is not detected even if the lead cartridge in use reaches the broken lead state in the second state, but the broken lead state is detected when the lead cartridge in use enters the first state. This is what I did.

〔Example〕

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

In FIG. 2, reference numeral 2 denotes a drawing head, which is configured to be controlled to move parallel to the table 6 in a predetermined direction by a controller 4 comprising a microcomputer. A DC motor 8 is fixed to the housing of the head 2, and a pinion 10 fixed to the output shaft of the DC motor 8 is connected to a drum 1 rotatably supported by the housing.
It meshes with the second gear 14. The gear 14 meshes with a gear on an input shaft of an encoder 16 fixed to the housing. A rope pulley 18 and 20 is rotatably supported by the housing, and a wire rope 22 wound around the drum 12 a plurality of times is hung on this pulley. 24
is a guide shaft fixed to the housing, into which the slider 26 is slidably inserted;
6 is fixed to the wire rope 22. The upper end of a push pin 28 is fixed to the slider 26. Reference numeral 30 denotes a frame fixed to the housing, a guide shaft 32 is fixed to this, and an elevating body 34 is slidably inserted into the guide shaft 32. The elevating body 34 has a fixed arm 3 for detachably holding the lead cartridge.
6.38, and a cartridge holding mechanism 43 consisting of swing arms 40 and 42 biased in the cartridge holding direction. The elevating body 34 is.

A known moving coil 44 is fixedly provided, and the moving coil 44 faces a yoke (iron core) fixedly provided to the frame 30. 45 is a pencil stocker, and this stocker is constituted by a rotating body 48. A rotating body 48 driven by a pulse motor 46 is disposed at one end of the table 6, and a fixed arm 50 is attached to the rotating body 48.
52 and the swinging arm 5 biased in the cartridge holding direction.
A plurality of well-known core cartridge holding mechanisms 56 consisting of 4 are provided at equal intervals in the circumferential direction.

Sensors 58 and 60 for determining the upper and lower limit positions of the push pin 28 are disposed in the housing of the head 2, and the sensors 58 and 60 detect a flag 61 fixed to the slider 26. It is configured. Said sensor 58.60. The encoder 16 is connected to the input end of the controller 4 as shown in FIG.
, DC motor8. The moving coil 44 and the XY motors 62 and 64 that drive the image line head 2 are controlled by the controller 4.
is connected to the output end of the RAM of the controller 4
A storage area map is provided for each lead cartridge holding mechanism 56, and the map includes a lead presence/absence flag,
A registration table for the remaining core amount of the lead cartridge is set. The address of each map corresponds to the angle signal of the rotating body 48.

Next, the operation of this embodiment will be explained with reference to the flowchart shown in FIG.

First, the lead cartridge 6 is attached to each holding mechanism 56 of the rotating body 48.
In this case, a flag representing unused is registered in the map of the unused lead cartridge 66.

The exchange operation of the lead cartridge/shiro 6 between the head 2 and the pencil stocker 45 is performed when the head 2 is moved from the pencil change point toward the stocker 45 by holding each other in the holding mechanism 43.
Move until 56 overlaps.

This is then done by returning to the pencil change point. This operation causes the holding mechanism 43 on the head 2 side to
When the lead cartridge 66 on the stocker 45 side is held in the holding mechanism 43 on the head 2 side, the head 2 side holds the lead cartridge 66, and the holding mechanism 56 on the stocker 45 side holds the lead cartridge 66 in the empty state. When empty, the lead cartridge 66 is held by the holding mechanism 56 on the stocker 45 side.

Now, when the holding mechanism 43 on the head 2 side receives the lead cartridge 66 from the holding mechanism 56 on the pencil stocker 45 side opposite thereto, and holds it with the fixed arm 36, 38 and the swinging arm 40° 42, The controller 4 determines the map of the lead cartridge 66 that the head 2 has picked up based on the angle signal of the rotating body 48 (step l), and determines whether or not this lead cartridge is the first cartridge installed in the head 2. Please judge step 2), if this is the first cartridge you are using, please use the DC motor 8.
is driven, the push pin 28 slows down from the predetermined highest position, and is inserted into the lead cartridge 66. When the tip of the push pin 28 comes into pressure contact with the upper end of the lead core in the lead cartridge, an overcurrent flows into the DC motor 8, and this overcurrent signal and the output of the encoder 16, which converts the downward movement of the push pin 28 into a pulse signal, are combined. The controller 4 measures and stores the amount of lead remaining in the lead cartridge (step 3). If the amount of lead remaining is greater than the specified amount (step 4), the controller 4 turns off the speed mode and releases the push pin 28. is raised by a predetermined amount, and the moving coil 44 is energized to raise the elevating body 34 by a predetermined amount to bring it into a so-called pencil-up state (step 5).Next, the push pins 28 and Elevating body 34
A drawing operation is performed by controlling the movement of the head 2 with respect to the table 6 while performing a pencil up-down operation by controlling the head 2 to move up and down with respect to the table 6. During this drawing operation, the sensor 60 is monitored (step 6). When the amount of lead remaining in the lead cartridge becomes extremely small, the flag 61 is detected by the sensor 60 (step 7).

When the sensor 60 outputs a lead breakage detection signal, drawing is interrupted, and the absence of a lead is registered in the map corresponding to the lead cartridge, so that the lead cartridge is not used thereafter (step 8). On the other hand, if the lead cartridge installed in the printing head 2 is not the first lead cartridge installed, the DC motor 8 is driven at high speed, and the push pin 28 is registered in the map in speed mode from the highest position. Step 9) to move to the desired position at high speed.
It is pressed into contact with the lead in the lead cartridge 66. When changing the pencil, the push pin 28 slowly rises to the R-up position, measures the amount of lead remaining in the lead cartridge 66, and stores this in the map. is set in two stages. When detecting the amount of lead remaining, that is, when using a lead cartridge that has been installed for the first time, and when changing pencils, it is determined whether there is more than a specified amount of lead, and if the amount of remaining lead is more than the specified amount. If there is no lead cartridge, the cartridge is configured to register no lead in the map and to not use that lead cartridge thereafter.

The prescribed amount of remaining core is set to be considerably larger than the amount of remaining core detected by the sensor 60.

Incidentally, during drawing, the sensor 60 detects lead breakage as described above. In this embodiment, the rotary body 48 that holds a large number of lead cartridges is arranged on the table side, but it is of course possible to provide the rotary body 48 or a moving body on the head side and have them hold a plurality of lead cartridges. It may also be used as a configuration.

〔effect〕

As mentioned above, the present invention can reduce the lead breakage state of the lead cartridge in two ways.
Since the steps are provided, a lead cartridge with a relatively large amount of lead remaining is selected, a drawing operation is performed with that lead cartridge, and during drawing, lead breakage is not detected until the amount of lead remaining becomes considerably small. This has the effect of greatly reducing the number of core breakages during drawing.

[Brief explanation of drawings]

1 is a flowchart, FIG. 2 is a side view, FIG. 3 is a front view of the head, FIG. 4 is a block diagram, and FIG. 5 is an explanatory diagram. 2... Print head, 4... Controller. 6...Table, 8...DC motor, 1
0...Pinion, 12...Drum,
14...Gear, 16...Encoder,
18゜20...Lobe pulley, 22...Wire rope, 24...Guide shaft, 26...
...Slider, 28...Push bottle, 3
0...Frame body. 32...Guide shaft, 34...Elevating body, 36
．． 38...Fixed arm, 40.42...Swinging arm, 44...Moving coil. 46...Pulse motor, 48...Rotating body. 50.52... Fixed arm, 54... Swinging arm, 43, 56... Holding mechanism, 58°6
0...Sensor, 62.64...Motor. 66... Lead cartridge patent applicant Aya Nishijima, patent attorney representing Muto Kogyo Co., Ltd....! :,,-
-,+

Claims (1)

[Claims] 1. Automatic drawing in which one of a plurality of lead cartridges is selected and placed directly under a push pin of the head, and the push pin presses the lead in the lead cartridge to draw a drawing line. In the machine, the state of broken lead in the lead cartridge is set to two stages: a first state in which the amount of remaining lead is relatively small and a second state in which the amount of remaining lead is relatively large. If the amount of lead remaining in the lead cartridge is detected by the amount of movement of the push pin and is in the broken state of the second state, the lead cartridge in the broken state is not used, and during drawing, Even if the lead cartridge in use reaches the broken lead state in the second state, the broken lead state is not detected, but the broken lead state is detected when the lead cartridge in use enters the first state. Features: Lead breakage detection method for automatic drafting machines.