JPH0121836Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is an automatic drafting method in which the consumable writing lead in the lead cartridge is pressed against the drawing surface by the pressure of a push shaft connected to the output shaft of a torque motor (pressurizing means). The purpose of this invention is to prevent relative movement control of the head with respect to the printing surface while the push shaft is unable to press the core. Conventionally, when selecting a lead in an automatic drawing machine that holds multiple consumable writing leads in a holder, the holder is moved a predetermined distance by a drive device and the desired writing lead is positioned directly below the push shaft. let Then, the push shaft is lowered and the upper end of the writing lead directly under the push shaft is pressed by the lower end of the push shaft to press the writing lead against the drawing surface to draw a drawing. However, if the center of the writing lead deviates even slightly from the center of the push shaft, when the lower end of the push shaft is lowered, it will not align with the upper end of the writing lead, and the lower end of the push shaft will be above the writing lead, causing The push shaft gets caught on the upper end of the cartridge or the upper surface of the holder, and the lower end of the push shaft cannot come into contact with the writing lead. If the drawing head moves relative to the drawing surface in this state and moves to the drawing operation, the drawing operation will be performed without the writing lead being pressed in the direction of the drawing surface by the push shaft.

The present invention is aimed at preventing the above-mentioned drawing errors, and is characterized by providing a detector for detecting a mismatch between the push shaft and the writing lead.

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

1 is a drawing board, 2 is a drawing head, and the drawing board 1 is
A controller (not shown) is controlled to move in a predetermined direction within a plane parallel to the top surface of the board and while maintaining a constant distance from the drawing surface.
is connected to. Note that the drawing board 1 may be replaced with a drum connected to a rotary drive device, and the drawing surface 1a side may be configured to be movable with respect to the head 2. Reference numeral 3 denotes a board fixed to the head casing, and a pulse motor 5 (or a servo motor) (drive device) is fixed to this. A board 7 for detecting the origin is fixed. A small hole 8 is transparently provided in the board 7, and a detection device 9 is fixedly installed in the movement path of the small hole 8. 10 is a holding tube fixed to the substrate 3, and a main shaft 11 is rotatably supported by this holding tube via a ball bearing. A cartridge holder 12 is detachably fixed to the main shaft 11, and holes 13 and 14 are formed in the upper and lower flanges of the cartridge holder along an axis perpendicular to the surface of the drawing board. The holes 13 and 14 constitute a cartridge holding guide. A large number of cartridge holding guide parts are provided on the upper and lower flanges of the holder 12 at predetermined intervals around the main shaft 11. A coil spring is disposed in a hole 13 transparently provided in the upper flange of the holder 12, and the coil spring causes the core cartridge 19 to
are resiliently held in place within the holes 13,14. A core 20 made of a lead core or other similar material is placed inside the core cartridge 19, and the core cartridge is held so that its lower end is exactly close to and facing the surface of the drawing board. 21 is a cartridge position detection device; 24 is a torque motor (pressurizing means) fixed to the casing 4; a pulley 25 fixed to the output shaft of the torque motor; and a pulley 25 fixed to the output shaft of the torque motor; An endless timing belt 27 is stretched between the pulley 26 and the attached pulley 26 with an appropriate tension. 28 is a guide shaft erected on the base plate 3, the upper end of which is connected to the casing 4.
It is fixed to a support piece 29 fixed to. A slide ball bearing 30 is attached to the guide shaft 28.
An elevating body 31 is fitted through the elevating body 31 so as to be movable up and down, and the upper end of a push shaft 32 is fixed to the elevating body 31. A mounting piece 33 is fixed to the elevating body 31,
The attachment piece 33 is fixed to the belt 27. 34 is a guide plate erected on the base plate 3, and limit switches 35 are installed on the upper and lower parts of the guide plate.
36 are arranged. Reference numeral 37 denotes a shaft that is slidably inserted into a slit 38 provided through the guide plate 34 via a ball bearing.
One end is fixed to the elevating body 31. 39
is a solenoid fixed to the casing 4, and a brake shoe 40 is fixed to the operating shaft of the solenoid, and the brake shoe 40 is connected to the pulley 25.
is facing. Reference numeral 50 denotes an object to be detected fixed to the timing belt 27, and a detector 51 is disposed in the head casing 4, located on the movement path of the object. The tip of the push shaft 32 is connected to a guide 4 fixed to the base plate 3 so as to be located on the arrangement circle of the core cartridge 19.
It is slidably inserted into the guide hole of No. 1. 46
is a gear fixed to the main shaft 11, and 45 is an intermediate gear.

Next, the operation of this embodiment will be explained. first,
In a state where the elevating body 31 is held in the raised position,
Lift up the head casing 4. Next, the core cartridge 19 is inserted into each cartridge holding guide portion of the cartridge holder 12, and the cartridge holder 12 is fixed to the main shaft 11 with its origin coincident. Next, the head 2 is returned to its original position and the tip of each core cartridge 19 is set to be close to the drawing surface on the drawing board 1. Next, in response to a command from the controller, the pulse motor 5 (drive device) is excited, and at the same time, the brake on the cartridge holder 12 is released. When the pulse motor 5 rotates, the main shaft 11 and the cartridge holder 12 rotate, and the cartridge holder 1
When the origin point 2 is detected, the pulse motor 5 is stopped, the cartridge holder 12 is stopped at the origin point, and a brake is applied to the holder 12. Next, the controller energizes the solenoid 39, and the brake shoe 40 separates from the pulley 25. Next, from the controller, torque motor 2
4 (pressurizing means) is energized, and the torque motor 2
4 starts forward rotation. At this time, the controller detects the current value of the torque motor 24 (pressurizing means). When the torque motor 24 starts rotating in the forward rotation direction, the push shaft 32 starts descending from the highest position shown in FIGS. 1 and 2. push shaft 3
2 is on its way down, and the lead cartridge 1 is directly below it.
When the push shaft 32 is unable to be inserted into the lead cartridge 19 due to contact with the upper end surface of the head of the lead cartridge 9, the push shaft 32 is prevented from further lowering. In this state, the detected object 50 is connected to the detector 51
has not been reached. When the push shaft 32 is prevented from descending, the current level of the torque motor 24 (pressurizing means) increases. The controller detects this current level increase and reverses the torque motor 24 (pressurizing means). The push shaft 32 rises due to the reverse rotation of the torque motor 24 (pressurizing means), and when the shaft 37 reaches the limit switch 35 and operates it, the solenoid 39 is turned off and the brake is applied to the pulley 25, and at the same time the torque motor 24 Power is turned off. Next, the pulse motor 55 is driven to rotate the cartridge holder 12 by a predetermined amount, and when the next core cartridge 19 is located directly under the push shaft 32, the pulse motor 5 is stopped and the cartridge holder 12 is fixed. do. Next, the solenoid 39 is energized to release the brake of the pulley 25, and the torque motor 24 is energized to rotate it forward. Torque motor 24
As the push shaft 32 is rotated forward, the push shaft 32 is lowered and inserted into the core cartridge 19 directly below it, and
When the detected object 50 passes the set position, the detected object 50 passes the detector 51, and the detector 51 is turned on. Furthermore,
When the push shaft 32 descends, the tip of the push shaft 32 comes into contact with the upper end of the lead 20 in the lead cartridge 19, presses it downward, and the lead 20 comes into contact with the drawing surface 1a. When the lead 20 comes into contact with the drawing surface 1a due to the pressing force of the push shaft 32, the current level of the torque motor 24 increases. The controller confirms that the push shaft 32 normally moves downward by detecting that the detector 51 is turned on and the current level of the torque motor 24 increases. After this confirmation, the controller reverses the torque motor 24 again, and
2 is set to the highest position, and a message indicating that preparation for drawing is completed is displayed.

Note that when the torque motor 24 is rotated forward, the torque motor 24 is rotated before the detector 51 is turned on.
When the current level of torque motor 2 increases,
4 is automatically reversed by a command from the controller, the push shaft 32 is raised, and the next lead cartridge is selected. When this core cartridge selection operation is performed continuously, there is an error in the positional relationship between the push shaft and the core cartridge, so the machine must be adjusted before drawing work. When the automatic switch is turned on after preparation for drawing is completed, the head 2 moves in a predetermined direction in a plane parallel to the drawing board 1 in response to a command from a controller (not shown). On the other hand, according to the command from the controller, solenoid 3
9 is turned on (energized), the brake shoe 40 is separated from the pulley 25, and the torque motor 24
is driven in the forward rotation direction. This allows pulley 25
rotates, and along with this, the elevating body 31 and the push shaft 32
descends. The push shaft 32 is inserted into one selected lead cartridge 19 immediately below it, contacts the upper end of the lead 20 in the lead cartridge 19, and presses the lead 20. The lead 20 is lowered by the pressing force from the push shaft 32, and stops when its lower end abuts the drawing surface 1a. This completes the pen-down operation. As the lead 20 descends, the frictional force therebetween causes the lead cartridge 19 to descend against the spring force holding it in place, and its lower end lightly contacts the work surface. The core 20 in contact with the drawing surface is pressurized by the torque of the torque motor 24 with a predetermined pressure suitable for drawing. This pressing force can be applied to the torque motor 24 as appropriate.
It can be changed by controlling the amount of electricity. Leaving lead 20 from the drawing surface (pen up)
is performed by reversing the torque motor 24 according to a command from the controller. When the torque motor 24 reverses, the push shaft 32 rises and the pressure applied to the lead 20 is released, and the lead cartridge 19
increases slightly due to the elasticity of the spring. As the lead cartridge 19 rises, the lead 20 slightly rises due to the frictional force therebetween, and the lead 20 is slightly separated from the drawing surface. When the lead cartridge 19 returns to a predetermined position slightly raised by the elasticity of the spring, the detection device 21 is activated. Based on the detection signal from the detection device 21, the controller issues a stop (OFF) command to the torque motor 24, turning the torque motor 24 OFF and stopping its reverse rotation. At the same time as torque motor 24 OFF,
Solenoid 39 is turned OFF, and as a result,
The brake shoe 40 is pressed against the pulley 25 by the elasticity of the spring, and the pulley 25 is fixed. This completes the pen up operation. A predetermined pattern is drawn on the drawing screen by the movement control of the head 2 and the pen up and down operations.

Incidentally, during drawing, as the core 20 wears out, the elevating body 31 and the push shaft 32 descend. When the core 20 in the core cartridge 19 is almost gone, the shaft 37
comes into contact with the movable switch piece of the limit switch 36 and presses it. When the limit switch 36 operates, the controller issues a reverse rotation command to the torque motor 24 based on the signal from the limit switch 36. Due to the reverse rotation of the torque motor 24, the push shaft 32 rises, and when its lower end is slightly separated from the upper end of the core cartridge 19, the shaft 3
7 contacts the limit switch 36, the limit switch 36 operates, the controller issues a stop command to the torque motor 24, the torque motor 24 is turned off, and at the same time the solenoid 39 is turned off.
When the brake switch 40 is turned OFF, the pulley 2
5 and the pulley 25 is fixed. Next, a drive command is issued to the pulse motor 5, and the worm 6
rotates, and the main shaft 11 and cartridge holder 1
2 rotates. When the next core cartridge 19 is located directly under the push shaft 32, the pulse motor 5
stops. This operation completes the replacement of the core cartridge 19. After the core cartridge is automatically replaced, the push shaft 32 descends, and if the push shaft 32 is caught on the head end surface of the cartridge 19 and is not inserted into the core cartridge 19, the next core cartridge 19 is inserted as described above. selected.

As is clear from the above description, the controller includes a detection means for detecting a change in pressure received by the push shaft 32 based on a drive signal of the torque motor 24, and a detector 5.
and determining means for detecting whether the generation timing of the object detection signal is before or after the generation timing of the received pressure change detection signal. Also, as is clear from the above explanation,
The set position of the push shaft 32 is a position where the lower end of the push shaft 32 is slightly inside the lead cartridge 19. However, the above setting position is not limited to this, and various design changes can be made depending on the structural situation within the scope of the purpose of the present invention.

Since the present invention is configured as described above, the drawing operation is not started in a state where the push shaft is caught above the lead and does not press the lead, and there is an effect that drawing errors can be prevented.

[Brief explanation of drawings]

The figure shows one preferred embodiment of the present invention.
The figure is a front sectional view, and FIG. 2 is a side sectional view. DESCRIPTION OF SYMBOLS 1... Drawing board, 2... Drawing head, 1a... Drawing surface, 3... Board, 5... Pulse motor (drive device), 9... Detection device, 11... Main shaft, 12...
Cartridge holder, 19... Core cartridge, 20... Core, 21... Cartridge position detection device, 24... Torque motor (pressurizing means), 32
... Push shaft, 50 ... Object to be detected, 51 ... Detector.

Claims (1)

[Scope of utility model registration request] A drawing surface 1a, a head 2 which is movable in a predetermined direction while maintaining a constant distance relative to the drawing surface 1a, a motor disposed on the head 2, and a motor connected to the output shaft of the motor. It consists of a push shaft 32 and a holder 12 connected to a drive device that holds a lead cartridge 19 in which a consumable writing lead 20 is placed so that its center axis can be positioned on the pressure line of the push shaft 32. In the device, a detected object 50 is provided to interlock with the push shaft 32, and a set position where the push shaft 32 can come into contact with the consumable writing lead 20 in the holder 12 from the highest standby position. a detector 51 that detects the detected object 50 and outputs an object detection signal when the detected object 50 is lowered to a lower position; a detecting means that detects a change in pressure received by the push shaft 32 based on a drive signal of the motor; and the detector 51 An automatic drawing machine comprising: a controller comprising means for receiving an object detection signal; and determining means for detecting whether the timing of generation of the object detection signal is before or after the timing of generation of the received pressure change detection signal.