JPH043920B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a writing device used in an automatic drafting machine.

BACKGROUND ART As shown in Japanese Patent Application Laid-Open No. 56-109796, a writing device is known in which a lead chuck mechanism in a lead holder changes the lead clamp position to feed out the lead.

Problems to be Solved by the Invention With such a writing device, when the lead becomes short and becomes unusable, it is necessary to remove the short lead, that is, the remaining lead, and replace it with a new lead. In this case, manually release the lead chuck mechanism to free the remaining lead, remove the protective pipe from the core pressure spring receiver, and remove the core press-fit tube with the remaining lead attached together with the protective pipe to remove the remaining lead. I drained it, pushed in a new wick, and reattached the protective pipe.

For this reason, the operation of discharging the remaining core and replacing it with a new core becomes extremely troublesome.

Means and action for solving the problem A core stock with a core chuck that constitutes a core chuck mechanism is inserted into a pipe that moves up and down by a motor, and the rise of this pipe is regulated with a weak force at an intermediate position. In addition, a stopper is provided for regulating the maximum rising position of the core stock with a strong force, and means for detecting the lowest point of the core chuck, and detecting the remaining core state based on a detection signal from the means for detecting the lowest point. a means for discriminating whether re-gripping or core replacement is to be performed; and when the determining means determines that re-gripping is to be performed, a normal operation command with a weak torque is output to the motor M, and when it is determined that the core is to be replaced, to the motor M. By providing a means for outputting a core replacement operation command with a stronger force than the stopper 4 which regulates with a weak force at an intermediate position, the operations of feeding out by re-gripping the core and discharging the remaining core and replacing it with a new core are automatically performed. It has been made possible to do so.

Embodiment FIG. 2 is a schematic front view of a writing device for a drafting machine. A base 1 that is moved in any direction by a moving mechanism (not shown) includes a writing instrument 2, a lifting mechanism 3, and a stopper 4.
In addition, the writing instrument 2 has a pipe 6 slidably inserted into a cylindrical case 5, a sleeve 7 is integrally attached to the upper part of the pipe 6 protruding from the case 5, and a core is provided. In addition to inserting the stock 8, a cap 9 is detachably attached to the upper part of the core stock 8, and the case 5 is attached to the holder 1.
A stopper 4 is located above the cap 9, and driving and driven rollers 11 and 11' are pressed against the sleeve 7 to form an elevating mechanism 3.

The writing instrument 2 is designed as shown in FIG.

That is, a core guide 20 is attached to the tip of the case 5, and this core guide 20 has a large diameter hole 22, a small diameter hole 23, and a core insertion hole 24 formed continuously and concentrically. A holding cylinder 25 is tightly fitted and fixed in the diameter hole 22, and there is a connection between the inside of the holding cylinder 25 and the small diameter hole 22.
A lead holding bush 26 was inserted so as to be able to move up and down, and the lead holding bush 26 was formed with a slit 27 that opened at the top so that it could be slightly deformed in the radial direction, and the lead inlet 26a was expanded upward. It has a funnel shape to facilitate insertion of the core, and is biased by a coil spring 28 to an upper position where the upper small diameter portion 26b fits into the opening 25a of the holding cylinder 25.
Moreover, it is configured to be able to move against the coil spring 28 to a lower position where it comes into contact with the bottom of the small diameter hole 23.

A pipe 6 is slidably inserted into the upper part of the case 5.
A chuck ring 29 is fitted and fixed to the lower part of the
The inner circumferential surface 29a is expanded downward to form a tapered shape, and a steel ball 31 fitted into the lower outer circumferential surface of the core chuck 30 is in contact with the inner circumferential surface 29a. This constitutes a core chuck mechanism.

The core chuck 30 is formed with a slit 32 opening at the bottom so that it can expand and contract in the radial direction, and the upper part of the core chuck 30 is slidably inserted into the upper part of the pipe 6. A core insertion hole 33 bored in the bottom 8a of the core stock 8 opens concentrically to the core chuck 30, and the chuck ring 29 and the lower end surface of the core stock 8 are fitted and fixed to the lower part of the core stock 8. A coil spring 34 is provided between the chuck ring 29 and the core chuck 30.
Since the steel balls 31 are urged in the direction of separation from each other and press against the inner circumferential surface 29a of the chuck ring 29, the core chuck 30 is compressed and deformed in the radial direction to firmly hold the core.

The stopper 4 has side pieces 40, 40 and a horizontal piece 41.
and form a downward U-shape, and the lower surfaces 40a of both side pieces 40
faces the slope 7'a of the large-diameter upper portion 7a of the sleeve 7, that is, the locking portion of the pipe 6, and the cap 9 faces between the both side pieces 40, and the lower surface 40a of the side pieces 40 faces the slope 7' When the cap 9 and the horizontal pieces 41 come into contact with the cap 9, the cap 9 and the horizontal pieces 41 are slightly separated, and when the pipe 6 rises any further, the side pieces 40 expand.

The driving/driven rollers 11, 11' are pinion-shaped and mesh with the rack teeth 7b of the sleeve 7, and the driving roller 11 is driven by a small DC motor M, so that the core chuck 30 reaches its lowest point. When descending, switch 50 is turned on.

The motor M is controlled in forward rotation, reverse rotation, and driving torque by control signals from the controller 60, and the controller 60 controls the switch 50.
A control signal is output to the motor M in a predetermined sequence according to the ON and OFF signals.

Next, the operation will be explained.

When the power is turned on and a drawing command is input, a normal rotation signal is sent from the controller 60 to the motor M as a normal operation command, the motor M rotates in the normal direction, and the pipe 6 passes through the sleeve 7 as shown in FIGS. At the same time, lower the lead chuck 30 and place the lead A into the lead holder 20.
The drawing is made by making it protrude further and contacting the paper B.

At this time, a current of a magnitude is supplied to the motor M to generate a torque sufficient to obtain a pressing force, that is, a pen pressure, on the paper B of the core A of a predetermined size.

When plotting, the lead A decreases and the lead chuck 30 gradually descends, and when it reaches the lowest point as shown in Figure 3c, the switch 50 is turned on.

The ON signal of this switch 50 is the controller 6
0, a reverse rotation signal and a weak torque signal (that is, low current) are sent to the motor M for a certain period of time, the motor is reversed with a weak torque, and the chuck ring 29 is raised via the sleeve 7 and pipe 6. The core chuck 30 continues to rise for a certain period of time via the coil spring 34.

As a result, as shown in FIG. 3d, the slope 7'a of the sleeve 7 comes into contact with the lower surface 40a of both sides of the stopper 4, and since the torque of the motor M is small, the sleeve 7
The core chuck 30 stops at an intermediate position because the both pieces 40 cannot be expanded on the slope 7'a, and the core chuck 30 again holds a position higher than the previously held position, that is, the core is re-held in its grip. Let's do it.

Note that when the lead chuck 30 rises, the lead A is held by the lead holding bush 26 of the lead guide 20 and does not rise, but the lead chuck 30 rises along the lead A.

In other words, the holding force of the lead chuck 30 on the core A based on the force of the coil spring 34 in the direction of separating the chuck ring 29 and the lead chuck 30 is slightly smaller than the holding power of the lead holding bush 26.

When the core chuck 30 stops at the aforementioned intermediate position for a certain period of time, the controller 60 sends a forward rotation signal to the motor M, which causes the motor M to rotate forward, and the core chuck 30 descends in the same manner as described above, so that the core chuck 30 is The lead A is further lowered by the amount that the lead A is held at a position above the lead holding position.

If you repeat the above-mentioned re-grip operation multiple times,
As shown in FIG. 4a, even when the lowest point is reached, the lead cannot be reattached, and in this case, it is necessary to replace the remaining lead with a new one.

Therefore, the time it takes for the core chuck 30 to start descending from the intermediate position, the switch 50 to turn ON, to rise to the intermediate position, to descend again, and for the switch 50 to turn ON, that is, the time it takes for the switch 50 to turn ON twice. The controller 60 detects this, and when the time is smaller than the set time, it determines that it is time to replace the core, and outputs a core replacement operation command to the motor M. That is, when the lead chuck 30 descends without holding the lead A, it descends quickly, so the time until the switch 50 is turned on changes depending on the length of the lead A.

The core exchange operation command is as follows.

As shown in FIG. 4a, when the controller 60 determines that it is time to replace the core when the switch 50 is turned on, it moves the base 1 to a predetermined remaining core discharge position, and after a certain period of time, the controller 60 reverses the direction with strong torque. A signal (i.e., a strong current) is sent to the motor M, which reverses with a torque greater than that during normal operation and raises the core chuck 30 as before.

As a result, when the slope 7'a of the sleeve 7 comes into contact with the lower surface 40a of the both side pieces 40 of the stopper 4 at the aforementioned intermediate position as shown in FIG. 4b, the torque of the motor M is large, so that the slope 7' A on both sides 4
Expand 0 and rise further from the intermediate position, Figure 4 c
As shown in the figure, the cap 9 is connected to the horizontal piece 41 of the stopper 4.
When the pipe 6 comes into contact with the sleeve 7 and rises further from this state, the core stock 8 does not rise, and the pipe 6 rises together with the sleeve 7, causing the chuck ring 2 to rise as shown in FIG. 4d.
9 rises against the coil spring 24, and the force with which the ball 31 tightens the core chuck 30 decreases and expands, thereby weakening the core holding force.

This state is maintained for a certain period of time, during which time the new lead A' passes through the lead insertion hole 33 and the lead chuck 30 and descends toward the lead guide 20, as shown in Figure 4e, above the remaining lead A. A new core A′ comes into contact with the .

As a result, the new core A' pushes out the remaining core A and discharges it to a predetermined remaining core discharge position.

Effects of the Invention The motor M is driven and controlled with a weak torque by the normal operation command from the controller 60, and the pipe 6
At the same time, by repeatedly moving the lead chuck 30 up and down between the intermediate position and the lowest point by the guide 4, the lead A can be re-held in the lead chuck 30 and sequentially fed out.

The motor M is driven and controlled with strong torque by the core exchange operation command from the controller 60, the core stock 8 is stopped, the pipe 6 is moved above the intermediate position, and the core chuck 30 and the chuck ring 2 are removed.
9 can be moved relative to the lead stock 8 to weaken the lead holding force, thereby allowing the new lead in the lead stock 8 to fall through the lead chuck 30 to the lead guide 20, discharging the remaining lead and replacing it with a new lead. Can be exchanged.

Therefore, the operation of discharging the remaining core and replacing it with a new core can be performed automatically, eliminating the need for troublesome manual operations.

[Brief explanation of drawings]

The drawings show embodiments of the present invention, FIG. 1 is a sectional view of a writing instrument, FIG. 2 is a schematic diagram of a writing device, and FIG. 3 a
- d are diagrams explaining the normal operation, and Figures 4a to 4e are diagrams explaining the remaining core discharging operation. 1 is the base, 4 is the stopper, 5 is the case, 6 is the pipe, 8 is the core stock, 29 is the chuck ring,
30 is a core chuck, 60 is a controller, and M is a motor.

Claims (1)

[Claims] 1. A cylindrical case 5 is fixed to the base 1, and a core guide 20 is provided at the tip of the case 5.
A pipe 6 is inserted into the case 5 so as to be movable up and down.
A core stock 8 is inserted into this pipe 6, and a core chuck 30 and a chuck ring 29 that constitute a core chuck mechanism are formed between the core stock 8 and the pipe 6.
The base 1 is provided with an elevating mechanism 3 equipped with a motor M that moves the pipe 6 up and down, and the core stock 8 is forced to the maximum raised position. A stopper 4 is provided to restrict the rise of the pipe 6 by a weak force at an intermediate position, and means for detecting the lowest point of the core chuck 30 is provided, and a means for determining whether the remaining core state is re-gripping or core replacement based on the detection signal; and when the determining means determines that re-gripping is the core, outputting a normal operation command with a weak torque to the motor M;
A writing device characterized in that, when it is determined that a lead needs to be replaced, a means is provided for outputting a lead change operation command to the motor M with a force stronger than that of a stopper 4 which restricts it with a weak force at an intermediate position.