JPH0124637B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a residual lead removal device in a drawing head of a drafting machine that supplies a consumable writing instrument lead, such as a graphite lead, to a paper surface in a lead holder. Such is the case.

(Prior Art) The present applicant previously disclosed in Japanese Patent Application No. 54-44551 that a predetermined pressure is applied and a lead is moved forward while being held in a lead holder configured to hold a long lead. A lead chuck mechanism is provided which releases the holding of the lead when wear of the lead is detected, and when the lead chuck mechanism is released, the lead holder is moved against the pressing force while leaving the lead in the head body. We have proposed a drawing head for a drafting machine that is equipped with a lead feeding mechanism for raising the lead to a predetermined pitch and changing the clamping position of the lead by the lead chuck.

(Problems to be Solved by the Invention) In the drawing head of a drawing machine that can hold a long lead as described above, the protective pipe provided above the main body of the head for holding the long lead is long. It is difficult to remove the remaining core easily.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a drawing head for a drafting machine in which the remaining core can be easily removed even if the core guide for holding the long core is a long holding pipe.

(Means for Solving the Problems) In order to achieve the above objects, the present invention provides a drawing head for a drawing machine having the following configuration.

Specifically, there is a lead holding mechanism on the top of the lead consisting of a protective pipe provided to hold the long lead, and a lead pressing mechanism that applies a predetermined pressure to the core of the lead chuck installed in the lead holder to provide core pressure. and a lead feed-out mechanism for changing the clamping position of the lead by the lead chuck of the lead holder when the lead wears out, and a lead up-down mechanism for raising and lowering the lead holder between the drawing stop position and the drawing position. A drafting machine comprising a chuck release mechanism equipped with means for freeing the chuck, and a core extracting mechanism comprising a core holder at the base of the core equipped with a pull-out means so as to be slidable in a protective pipe. This is a device for removing core residue in the printing head of the printer.

The core holder guided by the protective pipe is formed of a member having a flange that engages with the engaging part formed at the lower end of the protective pipe, and the holding pipe is constructed so that it can be freely pulled out from the head main body. Alternatively, the core extraction mechanism is constructed by attaching one end of a long extraction thread to a core holder.

(Function) The present invention frees the remaining lead held by the lead holder by lowering pressure on the lead chuck using the operating button of the chuck release mechanism, and in this free state, removes the lead holder together with the remaining lead using a protective pipe or a pull-out thread. It can be removed from the top of the head body.

(Example) The embodiments shown in the drawings will be described below.

The ones shown are a chuck mechanism A installed inside the lead holder, a lead pressure mechanism B that applies a predetermined core pressure to the lead holder, and a lead holder provided at the top of the lead to hold a long lead. Mechanism C, a holding mechanism D for the lower end of the lead, a lead up-down mechanism E for raising the lead for drawing, a lead feeding mechanism F for changing the clamping position of the lead by the lead chuck when the lead is worn out, a lead chuck release mechanism G, and It consists of a core breakage detection mechanism H.

First, we will explain the core pressing mechanism B which applies a predetermined pressure to the core holder to apply core pressure, and the core holding mechanism D provided on the upper part of the core to hold the long core.

In Fig. 1, 13 is the plotter head main body 1.
It is a core pressure spring receiver that stands upright with respect to a holder 14 fixed to the holder 14, the base of which is screwed through a connecting portion 13b, and a protective pipe 12 passing through the center. This protective pipe 12 is press-fitted into the cap 13a of the core pressure spring receiver 13, and the core pressure spring 15 wound around it is wrapped around the cap 13a.
It is interposed between the lower end of 3a and the upper end of a detection body holding cylinder 8 that moves up and down integrally with the core holder 4, which will be described later.

The upper part of the detector holding cylinder 8 is housed in the inner space of the connecting cylinder 13b, and is moved up and down using this as a guide.

As described above, since the core pressure spring 15 is supported by the holder 14 via the core pressure spring receiver 13, the detection body holding cylinder 8 is supported by the core pressure spring 1.
5, a predetermined pressure is applied to the lead holder 4, and core pressure is applied to the lead held by the chuck of the lead holder 4.

Since the protective pipe 12 is provided, the core is supported by this, and the longer the protective pipe is, the longer the core can be held.

The lower part of the illustrated protection pipe 12 is inserted into the inner cavity 8a of the detection body holding cylinder 8, and the lower part has an engaging part 12.
a is formed, and has a long core press-fitting cylinder 47b as a core holder into which the end of the core a is press-fitted, and a movable body pressing member 47 that slides inside the protection pipe 12 has a collar portion 47a. Yes, this is protection pipe 1
2 is engaged with the engaging portion 12a when the cap 2 is pulled out from the cap 13a.

The core press-fitting tube 47b is inserted into a core chuck mechanism, which will be described later, so that the length of the remaining core can be made as short as possible.

That is, when the core press-fit tube 47b is inserted into the core chuck and the detection mechanism described later is activated, the core press-fit tube 4
The shorter the distance between the lower end of 7b and the attachment tube of the core tip holder (described later), the less core remains.

Next, the holding mechanism D at the lower end of the core will be explained.
The lead holder guide cylinder 3 guides the raising and lowering of the lead holder 4, and its lower end is fixed to the base 2.

The spring receiver 18 is screwed into the lower end concave hole 3a of the lead holder guide cylinder 3, and the lead tip holder attachment cylinder 16, which slides in the inner hole 18a of the spring receiver 18, is screwed into the lower end of the inner hole 18a of the spring receiver 18. The spring 20 in the inner hole 16b of the tip holder mounting cylinder 16 is also received by the nut 19.

Further, a rubber gasket 17 is held in the saucer of an inverted bottle-shaped nib holder 16a provided at the center of the nib holder mounting tube 16, and the inner diameter of the center hole of the rubber gasket is slightly smaller than the outer diameter of the lead a. The core is held by friction, and the upper end of the center hole of the rubber packing 17 is formed into a funnel shape to facilitate insertion of the core into the center hole from above.

Since there is a clearance between the upper end of the spring receiver 18 and the upper end of the lead tip holder mounting cylinder 16, when the lead is fed out, the rubber gasket 17 initially resists the force of the spring 20 by this clearance.
Due to the frictional holding force, the lead tip holder mounting cylinder 16 descends together with the lead a, and the nut 19 restricts the lowering stop position.

This stopping position forms a certain distance between the tip holder 16a of the tip holder mounting tube 16 and the surface of the paper, and from the position where the tip holder mounting tube stops, the lead a is further affected by the frictional holding force of the rubber packing 17. Resist the lead tip holder mounting tube 1 by the amount of time 〓.
6 protrudes from the lead tip holder 16a.

The length of the lead protruding from the lead tip holder 16a is long enough to prevent the lead from breaking.

Once the tip holder 1 of the tip holder mounting tube 16 is
The core protruding from 6a rises while maintaining its protruding length due to the frictional holding force of the rubber packing 17.
The lead tip holder mounting cylinder 16 also rises together with the lead within the range of the clearance.

The above-mentioned clearance is changed depending on the degree of screwing of the nut 19.

When there is no lead, the lead tip holder mounting cylinder 16 is automatically lifted by the spring 20.

Further, in the space 21 of the lead holder guide tube 3 between the spring receiver 18 and the lead holder 4, there is a core holder 2 supported from above and below by springs 22, 22a.
3 is internally movable up and down, and a core insertion tube 23a is provided at the center of the core receiver 23.

The entrance of the core insertion tube 23a is formed into a funnel-shaped hole to facilitate insertion of the core a.

The upper end of the spring 22 is in contact with the lower end of the lead holder 4, and the lower end of the spring 22a is in contact with the upper end of the spring receiver 18.

By having the core support 23 as described above, the lower end of the lead is supported and the lead can be prevented from being broken.As the lead holder 4 descends in the guide tube 3 as the lead wears out, the core support 23 is constantly attached to the core support 23. 23 descends while being located in the center of the space, thereby preventing buckling of the core between the lower end of the core chuck 5 and the rubber packing 17 of the core chuck mechanism, which will be described later.
The lower end of the core can be held completely.

Note that the lead holder guide tube 3 is fitted into the base 2 of the plotter head main body 1 from above,
Since it can be fixed to the base 2 with a set screw (not shown), it can be disassembled from the base 2 in conjunction with the mounting structure of the tip holder mounting tube 16 described above. Note that 16c is an air vent hole provided in the tip holder mounting tube 16.

Next, the lead up-down mechanism E for raising and lowering the lead for drawing will be explained.

That is, the clutch body 25 is fitted onto the outer periphery of the lead holder guide tube 3 and is slidable up and down, and the inner surface is formed into an upwardly inclined tapered surface in a mortar-shaped portion 25a above the clutch body. A taper ring 26 is installed inside and is fixed by a cover member 25b screwed onto the mortar-shaped portion 25a.

A plurality of balls 27 are interposed between the taper ring 26 and the outer periphery of the lead holder 4, and are pressed downward by a spring 28 via its seat plate 28a.

Note that the ball 27 is restricted from descending by the upper end surface of the lead holder guide cylinder 3. Reference numeral 29 is a core up/down solenoid supported by the plotter head body 1 via a bracket 30, and its suction disc 29a is drawn down by a coil.
The tip of the lever 31 fixed to the operating shaft 29b integrated with the clutch body 25 engages with the engagement groove 25c of the clutch body 25,
The clutch body 25 is raised and lowered.

Further, a lifting spring 3 is installed between the lower end of the lever 31 and the cap 32 attached to the base 2.
3 is interposed to urge the lever 31 upward.

Therefore, when the solenoid 29 is de-energized, the lever 31 is raised by the spring 33.
Raise the clutch body.

Above the solenoid 29 is a stopper 35 supported by the plotter head body 1 via a bracket 34, which limits the upper limit of movement of the suction disc 29a.

The core up-down mechanism is as described above, so when the solenoid 29 is turned on, the operating shaft 29b
The taper ring 26 is then lowered together with the clutch body 25 via the lever 31.
The ball 27 is restricted from descending at the position where it hits the upper end surface of the lead holder guide cylinder 3, and since the inner surface of the tapered ring 26 is formed into an upwardly sloping tapered surface, the ball 27 is prevented from coming into contact with the lead holder 27. The degree of the locking is relaxed, and the so-called locking clutch is released, whereby the core holder 4 becomes free and can be freely lowered by the core pressure spring 15.

Next, when the solenoid 29 is turned OFF, the lever 31 is raised by the lifting spring 33, and the clutch body 25 is raised via the lever 31.

Then, since the ball 27 is pressed downward by the spring 28, the clutch body 25
As the tapered ring 26 rises, it slides on the tapered surface of the tapered ring 26, thereby increasing the degree of contact with the lead holder 4, so that the lead holder 4 and the tapered ring 26 are fixed, and the lead holder 4 is raised. It happens.

Next, although the order is reversed, the chuck mechanism A and the lead feeding mechanism F will be explained.

That is, regarding the chuck mechanism A, the aforementioned lead holder 4 is fitted into the lead holder guide tube 3 erected on the base 2 of the plotter head main body 1 so as to be able to move up and down, and the lead a is attached at the center of the lead holder 4. A core chuck 5 for clamping is fitted in the axial direction.

A core insertion hole 5a is provided at the center of the main body of the core chuck 5, and the outer peripheral surface 5b of the lower end thereof is formed into a cylindrical portion with a large diameter, and several slits are formed in the axial direction from this lower end to the upper middle portion of the present invention. A tightening collet 9 is formed at the lower end.

The inner surface of the lead holder 4 corresponding to the collet 9 is formed into a tapered guide surface 7 that widens toward the end, and the collet 9 has a recess 9a in the center thereof into which the ball 6 is fitted.

A balance spring 11 is interposed between a large-diameter portion 5c at the top of the main body of the lead chuck 5 and an upper step portion 4b forming a tapered guide surface 7 on the inner surface of the lead holder 4, and holds the lead chuck 5.

This balance spring 11 has no force to push up or down the lead chuck 5, but merely supports the lead chuck 5 against the lead holder 4.

Next, to explain the core feeding mechanism F, a core feeding rotary solenoid 38 is attached to the plotter head main body 1 via a bracket 38a.
An upper end of a hook lever 37a is pivotally supported on an arm 37 directly connected to a rotating shaft 38b of the rotary solenoid 38.

The hook portion of the hook lever 37a engages from below with the large upper diameter flange 8b of the detection body holding cylinder 8.
Further, a sensor shielding plate 39 is fixed to this upper large-diameter flange 8b, and a sensor 40 consisting of a light emitting element and a light receiving element is fixed to the blotter head body 1 correspondingly.

Therefore, the core holder 4 is the core pressure spring 15.
When the pressure is lowered in the lead a and moves down inside the lead holder guide cylinder 3 as the lead a wears out, the rotary solenoid 38 is OFF, so the hook lever 37
a is in a free state and descends while being engaged with the large upper diameter flange 8b of the detection body holding cylinder 8 which descends together with the lead holder 4.

When the sensor blocking plate 39 is inserted between the light emitting element and the light receiving element of the sensor 40 and detects that a certain amount of the core has been consumed, a signal is sent to the rotary solenoid 38 electrically connected to the sensor shielding plate 39. , this is turned ON, and the hook lever 37a is raised via the arm 37, and the detecting object holding cylinder 8, which is engaged with the hook lever 37a, is raised until it abuts against the holder 14.

Note that a sector gear is provided in place of the arm 37,
A rack that engages with this may be provided on the large upper diameter flange 8b.

Next, the chuck release mechanism G will be explained. 4
Reference numeral 8 denotes a chuck release operation lever, which is inserted from above the plotter head main body 1, further hangs down from the insertion hole 8c of the large upper diameter flange 8b of the detecting body holding cylinder 8, and the middle portion is inserted into the detecting body holding cylinder 8. Lower diameter large tsuba 8
Dog-shaped link 49 pivoted 50 in groove 8e of d
It is pivoted 51 at one end, and the dogleg-shaped link 4
The other end 52 of the core chuck 9 is further bent into an L shape and abuts against the upper end of the core chuck 5.

Note that 48a indicates an operation button provided on the above-mentioned part of the chuck release operation lever 48.

Further, instead of the link 49, a lever may be used which is pivotally supported in the middle.

Since the chuck release mechanism G is constructed as described above, when the operating rod 48 is pressed down using the operating button 48a, the core chuck 5 is pushed down via the link 49, and the collector 9 is moved against the spring 11. As the lead holder 4 moves in the direction of expansion of the tapered guide surface 7, the ball 6 descends while being fitted into the recess 9a, so that when the collet 9 is pressed, the lead chuck 5 becomes free.

Note that 8f is a center hole formed in the lower large-diameter collar 8d of the detecting body holding cylinder 8, into which the core is inserted and the tip 52 of the link 49 faces.

Next, the core detector H will be explained.

Reference numeral 53 denotes a sensor consisting of a light emitting element and a light receiving element, which is fixed on the large diameter upper part flange 8d of the detection body holding cylinder 8, and 53a indicates the light emitting element.

The sensor shielding plate 55 that blocks the light from the light projecting element 53a has an inverted V shape, and the sensor shielding plate 55 is inserted into the groove 54a of the movable plate 54 that slides in the inner hole 8a of the detection object holding cylinder 8. The top is pivot 55
It has been c.

Therefore, one arm 5 of the sensor blocking plate 55
The other arm 55b is heavier than the other arm 5a, and therefore the center hole 54b of the moving plate 54
The tip of the arm 55a is energized so that it is always in contact with the core press-fit tube 47b or the core inserted therein.

The arm 55b blocks light from the light emitting element 53a of the sensor 53.

The moving plate 54 is supported by a spring 56 at the bottom of the inner hole 8a of the detection body holding cylinder 8.

Note that 8g is a slit groove provided in the cylindrical body 8 so that the sensor shielding plate 55 can be moved up and down without any trouble.

Since the core detection mechanism H is configured as described above, if there is no core, there is nothing to support the arm 55a of the sensor shielding plate 55, so the sensor shielding plate 55 swings in the direction of the hour hand in the figure, and the arm 55b is used to rotate the arm 55a. The light from the optical element 53a is blocked.

Therefore, a signal is sent from the sensor 53 to an alarm device (not shown) to issue an alarm or to disable the drawing machine.

In addition, if there is a core but there is too much remaining core to use it, the core press-fitting tube 47b is inserted into the center hole 54b of the moving plate 54, and the moving body pressing member 47 with the flange 47a presses down on the moving plate 54. Moving plate 5
4 is lowered against the spring 56, and accordingly the sensor blocking plate 55 is also lowered, and one arm 55b blocks the light from the light emitting element 53a, and similarly sends a signal to the alarm device. whether to emit
Or the drawing machine can be disabled.

From the above, 1 consisting of the sensor blocking plate 55
With one detection device, it is possible to detect both cases where the core is missing and cases where the remaining core is too small to be used.

When the detection device is in operation as described above, the lead press-fitting cylinder 47b is inserted into the lead insertion hole 5a of the lead chuck 5, and the distance between the lower end of the lead press-fitting cylinder 47b and the tip holder mounting cylinder 16 is By having a short structure, the length of the remaining core is shortened.

Therefore, the longer the core press-fitting tube 47b is, the shorter the length of the remaining core can be.

Now, when inserting the lead into the printing head, first press-fit the lead end into the lead press-fitting tube 47b, and then
The lead is inserted from above, but the solenoid 29 is normally off when drawing is stopped, so the locking clutch 25 is locked and the lead holder 4 is raised based on the operation described above. ing. Therefore, the solenoid 29 is turned on to lower the lead holder 4 so that the lead can land on the drawing board surface when the lead is down.

This is because if the lead is inserted with the lead holder 4 in the raised state until it protrudes below the lead tip holder 16a, depending on the amount of protrusion, when the lead holder 4 is lowered afterwards, the lead will not be in the drawing position. This is because the lead holder 4 may still descend after hitting the surface, and in that case, the lead will break.

Then, the lead a is inserted into the lead chuck 5 through the protective pipe 12, the lead insertion hole 54b of the movable plate 54, and the center hole 8f in the lower diameter large collar 8d of the detection body holding cylinder 8. Then, due to the friction between the lead chuck 5 and the lead a, the lead chuck 5 descends a little and changes its relative position with the lead holder 4, so the ball 6 is pushed toward the larger diameter part of the lead holder taper guide surface 7.
Since the pressure on the tightening collet 9 by the ball 6 is released, the core chuck 5 becomes free. Therefore core a
The tip holder 16a of the tip holder mounting tube 16
It can be inserted until it protrudes from and touches the drawing board surface.

At this time, the lead tip holder mounting tube 16 descends somewhat. After inserting core a, solenoid 2
9 is turned OFF and the lead holder 4 is raised.

Then, the spring 20 causes the lead tip holder mounting cylinder 16 to rise, and the lead also moves to its rubber gasket 1.
It rises with a holding power of 7.

As the lead chuck 5 rises, the lead chuck 5 rises due to friction with the lead a and changes its relative position with the lead holder 4, so the lead chuck 5 operates in the opposite manner to the previous one and becomes locked.

Next, turn on the solenoid 38.

At this time, the lead holder 4 was once locked.
is the detection object holding cylinder 8 via the hook lever 37a.
Since the lead is further pulled up through the lead chuck 5, the locked state is released, and the lead chuck 5 is subsequently held in the lead tip holder 16a by friction.
The lead holder 4 rises with the lead free and the lead remaining, and the position where the lead chuck 5 clamps the lead is changed.

Next, turn on solenoid 29 again for drawing. Then, the locking clutch 25 is unlocked under the above-mentioned operation, so that the lead holder 4 becomes free and freely moves down by the core pressure spring 15.

At this time, since the tip holder mounting tube 16 is initially stopped by the spring 20, the rubber gasket 17
The lead a held by the lead chuck 5 is stopped.
The movement of the core a is also prevented by the friction of the core a.

Even though the movement of the lead chuck 5 is prevented in this way, the lead holder 4 presses the tightening collet 9 via the ball 6 with the small diameter portion of the tapered guide surface 7 of the descending lead holder 4. Core chuck 5 is locked.

When the lead holder 4 continues to descend, the lead tip holder mounting cylinder 16 moves down against the spring 20 due to the friction between the lead a and the rubber packing 17.

Then, the lead tip holder mounting cylinder 16 abuts against the nut 19 and its descent is stopped, and the lead a comes into contact with the drawing surface and stops.

In this case, the lead holder 4 continues to descend, so that the lead chuck completely clamps the lead.

In this way, writing pressure is applied to the lead by the core pressure spring to draw a picture, but in this drawing state, the lead remains locked by the lead chuck mechanism.

Next time, when raising the core to stop drawing,
Turn off solenoid 29.

The locking clutch is then locked under the operation described above, and the lead holder 4 is raised.

At this time, as the lead holder 4 rises, the lead holder mounting cylinder 16 also rises by its spring 20, so the lead chuck 5 also rises together with the lead a held by the rubber gasket 17 of the lead holder mounting cylinder 16. The relative position with respect to the holder 4 does not change, so the lead chuck mechanism remains in the locked state in the drawing state.

In this way, the lead tip holder mounting cylinder 16 abuts against the upper end of the inner space 18a of the spring receiver 18 and stops, thereby moving the lead away from the drawing surface.

Next, to explain the case of feeding out the lead, when the lead wears out regardless of whether the solenoid 29 is ON or OFF, the sensor blocking plate 39 and the sensor 40
A signal is sent to the core feed rotary solenoid 38 based on the detection means, which turns on, rotates the arm 37, and releases the hook lever 37.
At step a, the upper large diameter collar 8b of the detection body holding cylinder 8 is raised until it abuts against the holder 14.

In this case, the lead holder 4 is forced to rise positively together with the cylinder 8, and the ball 27 is pushed upward against the force of the spring 28 to release the locking clutch.

Therefore, the lead holder 4 continues to be used as the hook lever 3.
It is raised at 7a.

At this time, as the lead holder 4 rises, the lead tip holder mounting cylinder 16 also rises by the spring 20, so the relative relationship between the lead chuck 5 and the lead holder 4 remains unchanged, the lead chuck mechanism continues to maintain the locked state, and the lead chuck 5 rises together with the lead holder 4.

Next, when the lead tip holder mounting cylinder 16 hits the upper end of the inner cavity 18a of the spring receiver 18 and stops, the lead chuck 5 also stops, and only the lead holder 4 continues to rise, so the mutual relationship between the lead chuck 5 and the lead holder 4 changes. changes, and the core is unlocked by the core chuck mechanism.

And the core chuck 5 is the balance spring 11
Since it is supported by the lead holder 4, it will later rise together with the lead holder 4.

As a result, the clamping position of the core chuck with respect to the core a is changed.

After a certain period of time, the rotary solenoid 38
When turned OFF, the arm 37 stops rotating and becomes free.

Next, since the pressure of the core pressure spring 15 is applied to the lead chuck 5, the lead holder 4 descends, but the lead tip holder mounting cylinder 16 is moved by its spring 20.
Since the core chuck 5 is at the rising stop position, the core chuck 5 is stopped due to friction with the core, and therefore the core chuck 5
The relative position between the lead holder 4 and the lead holder 4 changes, and the chuck mechanism becomes locked.

Even when the chuck mechanism is locked in this way, the lead holder 4 still descends, so the lead tip holder mounting cylinder 16 also descends against the force of the spring 20 due to the friction between the lead a and the rubber packing 17.

When the tip holder mounting cylinder 16 stops at the downward stop position relative to the nut 19, the tip of the tip comes into contact with the drawing surface and stops, but at this point the chuck mechanism completely clamps the lead and maintains the drawing state. I can continue.

After repeating the above operations, when the lower end of the movable pressing member 47 having the flange portion 47a abuts against the movable plate 54, the movable plate 54 is pressed down against the spring 56, and the sensor shielding plate 55 is lowered.

In this case, one arm 55a of the sensor shielding plate 55 comes into contact with the core press-fit tube 47b and descends while contacting the core press-fit tube 47b without changing its posture, and the other arm 55b removes light from the light emitting element 53a. Shut off the light and send a signal to the control to issue an alarm or disable the drafting machine.

Therefore, a new core is replaced.

To replace a new lead, you must first remove the remaining lead, but in that case, first press the operation button 48.
Press down on the operating rod 48 with a to release the core chuck mechanism and free the remaining core, and then remove the protective pipe 1.
2 upward from the core pressure spring receiver 13. Then, the flange 47a of the moving body pressing member 47
is engaged with the engaging portion 12a, and the core press-fit tube 47b with the remaining core attached is removed together with the protective pipe 12. In that case, since the chuck mechanism is free, there is no need to worry about this and the tip holder mounting tube 1
The remaining core can be removed from the rubber packing 17 of No.6.

Then, the remaining core is removed from the core press-fitting tube 47b of the movable body pressing member 47 that has been pulled out, and a new core is pushed into the core press-fitting tube 47b and is again attached to the image head together with the protective pipe 12.

In order to remove the remaining core, in advance, one end of a long extraction string is tied to the flange 47a of the movable body pressing member 47 as shown in FIG. 4, and the other end is tied to the hole 47c of the flange 47a.
Alternatively, the thread may be stretched out from the protective pipe 12, and when replacing the core, the thread may be pulled and pulled out from within the protective pipe 12 while the protective pipe 12 is attached to the printing head.

Alternatively, the end of the long drawn-out thread may be directly adhered to the core without using the movable body pressing member 47, or it may be adhered using an appropriate attachment member, and the drawn-out thread may be used to take it out from inside the protective pipe 12. good.

In this case, when the core runs out, the arm 55a of the sensor shielding plate 55 comes into contact with the flexible thread and swings freely, allowing the control device to work.

The lead is replaced as described above, but if the drafting machine is operated without replacing the lead, the lead breakage detection mechanism operates based on the operation described above and issues an alarm.

FIG. 5 shows an automatic drawing machine equipped with the above-described drawing head.
A y-axis rail 43 is slidably provided on the y-axis rail 42 via x-cursors 44, 44, and a print head 45 is slidably mounted on the y-axis rail 43.

And the x cursors 44, 44 and the drawing head 4
5 is equipped with a pulse motor or an arbitrary servo motor which is rotated by a pulse signal from a pulse transmitter (not shown), thereby moving the x cursors 44, 44 and the drawing head 45 to arbitrary positions.

If a plurality of lead holders are provided in-line in the drawing head 45, drawing can be carried out for an even longer period of time.

In addition to the drawing head shown in the drawings, the drawing head of the drafting instrument can also be used in a drawing head equipped with a turret type lead holder.

(Effects of the Invention) In any case, the present invention has a feature in that the remaining core can be easily taken out because a member is provided at the base end of the core for pulling up the remaining core toward the upper side of the head main body. be.

[Brief explanation of drawings]

Fig. 1 is a cutaway front view of the device of the present invention, Fig. 2 is a cutaway side view of the same as above, Fig. 3 is an enlarged sectional view of the main parts of the device of the present invention, and Fig. 4 is a diagram showing how the cored thread is used. FIG. 5 is a perspective view of the Cartesian coordinate drawing device. A lead chuck mechanism A installed in the lead holder,
3... Core holder guide tube, 4... Core holder,
5... Core chuck, 6... Ball, 7... Taper guide diagram, 9... Tightening collet, 11... Balance spring, core pressure mechanism B that applies a predetermined pressure to the core holder to provide core pressure, 13 ... Core pressure spring receiver, 14 ... Holder, 15 ... Core pressure spring, holding mechanism C on the upper part of the core provided to hold the long lead, 8 ... Cylindrical body for holding the detection object, 1
2... Protective pipe, 47b... Holding mechanism D for the lower end of the core press-fit cylinder as a lead holder, 16... Lead holder mounting cylinder, 17... Rubber gasket, 18... Spring receiver, 19... Nut, 20... ... Spring, 21 ... Space, 22, 22a ... Spring, 23 ... Core holder, Lead up-down mechanism E for raising and lowering the lead for drawing, 25 ... Clutch body, 26 ... Taper ring, 27 ... Ball ,
28...Spring, 29...Solenoid, 29
a... Operating shaft, 31... Lever, lead feeding mechanism F for changing the clamping position of the lead by the chuck when the lead wears out, 37... Arm, 37a...
...Hook lever, 38...Solenoid, 39,40...
...Sensor, chuck release mechanism G, 48...Operation rod, 49...Link, core breakage detection mechanism H, 47...
... Moving body pressing member, 54... Moving plate, 53, 55
……sensor.

Claims (1)

[Claims] 1. Core pressure is maintained by applying a predetermined pressure to the core holding mechanism on the upper part of the core consisting of a protective pipe provided to hold the long core and the core of a core chuck installed in the core holder. It is equipped with a lead pressure mechanism, a lead feeding mechanism for changing the clamping position of the lead by the lead chuck of the lead holder when the lead is exhausted, and a lead up-down mechanism for raising and lowering the lead holder between the drawing stop position and the drawing position. In this type, a chuck release mechanism is provided with a means for freeing the lead chuck, and a lead holder at the base of the lead is provided with a pull-out means so as to be slidable inside the protective pipe, and a lead extraction mechanism is provided. A residual core removal device in a drawing head of a drawing machine comprising: 2. The core holder guided by the protective pipe is formed of a member having a flange that engages with the engaging part formed at the lower end of the protective pipe, and the protective pipe has a core extractor configured to be freely drawn out from the head body. A residual core removing device in a drawing head of a drafting machine according to claim 1, having a mechanism. 3. A residual core removing device in a drawing head of a drafting machine according to claim 1, which has a core removing mechanism in which one end of a long drawn thread is attached to a core holder.