JPH044136B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention involves welding both ends of a long ribbon in the manufacturing process of endless ribbons such as ink ribbons used in printers, and then cutting off the remaining ends. Regarding equipment.

[Conventional technology]

Various printers are used as printing devices for word processors and computers, but among them, wire dot printers, which print by striking a thin wire onto paper at high speed via an ink ribbon, are the mainstream.

The ink ribbon used in wire dot printers is made of synthetic fiber cloth such as nylon impregnated with ink, and is generally an endless ribbon that can be used in continuous circulation without the inconvenience of replacing or rewinding. .

A widely used method for manufacturing such endless ribbons is to weld and join both ends of a long ribbon using an ultrasonic welder. There are two methods for welding and joining: one is by fusion welding (type A), and the other is by cutting off the remaining end after welding (type B).

The type A method is illustrated in Figure 4a and
As described in Japanese Patent No. 54-2235, both ends 1a and 1b of the ribbon 1 are overlapped in an X-shape so that the same surfaces (side A-A) face each other, and the central part is cut at an acute angle. An ultrasonic welding horn 3 is attached to a pedestal 2 having a top part.
While crimping and welding by applying ultrasonic vibration, the remaining end 1c is simultaneously cut by fusing. Next, when the ribbon is unfolded, the weld line 4 becomes a protrusion as shown in Fig. 4b, so it is shaped flat with an ultrasonic shaping horn as described in Japanese Patent Publication No. 55-5407 to form an endless ribbon. shall be.

On the other hand, in the method of type B, as shown in FIG.
The center part is welded to a pedestal 2 having a smooth top with a width of about 0.5 mm by applying ultrasonic vibration while pressing it with an ultrasonic welding horn 3. Next, the remaining end 1c is cut off near the weld line 4, and the weld line 4 formed as shown in FIG. 5b is shaped into an endless ribbon in the same manner as described above.

In either method, the welded wire 4 becomes resinous and loses its properties as a fiber, and impregnation with ink disappears, causing print chipping, and the ribbon's tensile strength and impact strength are reduced. Therefore, both of the above methods are carried out by optimizing the welding conditions, but with method type A, the tensile strength of the endless ribbon obtained is only about half that of type B, which is not satisfactory in terms of strength. isn't it. The reason for this is thought to be that, as can be seen from the cross-sectional shapes of the weld lines in FIGS. 4b and 5b, the tensile force becomes a shearing force in type B, whereas it becomes a peeling force in type A.

However, although type B method is superior in terms of strength, it is not widely used because it is difficult to cut off the remaining end 1c after welding. That is, it is necessary to cut and remove the remaining end 1c as close as possible to the weld line 4, but even if special scissors or other blades are used, this is currently done manually and with great care. This resulted in large variations in quality and extremely low production efficiency.

[Problem that the invention seeks to solve]

In view of the above-mentioned conventional circumstances, the present invention automatically cuts off the remaining ends after welding both ends of the ribbon according to the method of type B, which has excellent strength, and has high strength and excellent quality. The purpose is to manufacture endless ribbons with high efficiency.

[Means for solving problems]

The present invention is a device for cutting off the remaining end of an endless ribbon welded by overlapping both ends of the ribbon on the entire surface along the longitudinal direction and welding at a weld line crossing the longitudinal direction; one edge in the longitudinal direction gradually changes from the other side to one side Two flat band-shaped guide plates formed into a blade shape by sloped surfaces that become thinner, and the two guide plates are placed facing each other with one edge parallel to each other and spaced apart, and the sloped surfaces are reflected from each other. a support stand supported at one end with one side of both guide plates parallel to each other and planes including one side of each guide plate close to each other; and two cutting devices provided on both sides of the two guide plates so as to be movable together along one edge parallel to each other of the guide plates.
It is equipped with two clamping devices.

As the cutting device, a cutting tool such as a cutter knife whose cutting edge is aligned parallel to the moving direction of the ribbon, or a laser beam can be used. However, when cutting with a knife, when tension is applied to the ribbon, the warp threads tend to come off leaving the weft threads behind, but when using a laser beam, the cut parts are welded and integrated, so the warp threads do not come off, allowing for high precision. This has the advantage of fast cutting speed.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus for cutting off the remaining end of an endless ribbon according to the present invention will be explained in detail with reference to the drawings.

As shown in FIG. 1, two clamp devices 5 that hold both end portions of the ribbon 1, which are stacked parallel to each other on the entire surface along the longitudinal direction, are fixed to a movable plate 7 that is integrally connected. , each clamp device 5 has a clamp head 6 made of cylindrical elastic rubber that is driven up and down. A movable plate 7 to which two clamp devices 5 are fixed can be linearly reciprocated along a guide rail 8 by a belt driven by a motor, a drive cylinder, or the like.

Between the two clamp devices 5, two flat band-shaped guide plates 9 are installed on the moving side of the clamp devices 5 with one end open and the other end fixed to the support stand 14. Each guide plate 9 has a tapered portion 11 in which one edge 10 in the longitudinal direction is a straight line halfway from the other end to the other end, and the one edge 10 is straight as shown in FIG. As shown in FIG. 3, it is formed into a blade-like shape by an inclined surface 12 that gradually becomes thinner from the other surface to one surface. These two guide plates 9 have straight portions of one edge 10 facing each other in parallel with an interval to form a guide groove 13, and an inclined surface 12.
are positioned vertically opposite to each other, and both guide plates 9
The two surfaces are parallel to each other, and the planes including the respective surfaces are brought close to each other, and the other end is fixed to the support base 14. One end of each of the two guide plates 9 is located between each clamp device 5 and the pedestal 2, and is opened at a distance so as to sandwich the pedestal 2. Further, the direction of the guide grooves 13 of the two guide plates 9 is directly above the direction of the weld line of the ribbon.

Preferably, a gap equal to the thickness of the ribbon 1 is provided between two planes including one side of each of the two guide plates 9, and a clamping surface of the ribbon 1 by the clamping device 5 is provided at a height between these two planes. Place it so that the top of the pedestal 2 is on top. Further, the distance between the opposing edges 10 is set to be the same as the width of the weld line.

A normal laser head 15 is installed above and below the guide groove 13 portion of the guide plate 9, and separates laser beams of equal energy from one laser oscillation device by combining a half mirror and a total reflection mirror. It is now ready for irradiation. As shown in FIG. 3, a laser beam (arrow) is emitted from a laser head 15a provided above one guide plate 9a onto a protruding slope 12 of a portion of the other guide plate 9b having a guide groove 13. is irradiated, and the laser beam from the laser head 15b below the other guide plate 9b is irradiated in the opposite direction.

Although a separately welded ribbon may be held in the clamp device 5 with the direction of the weld line aligned with the guide groove 13, as in this embodiment, both ends of the unwelded ribbon 1 are held in parallel and overlapped, It is also possible to sequentially perform welding of the ribbon and cutting off the remaining end using the same device.

That is, as shown in FIG. 1, a conventional ultrasonic welding horn 3 and a pedestal 2 are installed between the open ends of two guide plates 9. The ultrasonic welding horn 3 and the pedestal 2 have a width that intersects the ribbon 1 in the longitudinal direction.
Any material that can form a weld line of about 0.5 mm may be used, but in this example, the pedestal 2 has a top corresponding to the weld line. Ultrasonic welding horn 3 and cradle 2
are arranged vertically opposite to each other between the two clamp devices 5 so that the direction of the top of the pedestal 2, that is, the direction of the weld line coincides with the moving direction of the two clamp devices 5. The ultrasonic welding horn 3 is connected to an ultrasonic oscillator and a vibrator (not shown) and is movable up and down, and simultaneously generates ultrasonic vibrations and welds the ribbon 1 when pressed against the fixed pedestal 2. There is.

[Effect]

As shown in FIG. 1, with both ends of the ribbons 1 stacked in parallel and one free end of the guide plate 9 inserted between the stacked ribbons 1, the stacked portions of the ribbons 1 are held together by two clamping devices. Tension and hold at 5. Since the two clamp devices 5 are fixed on both sides of the pedestal 2 at different distances from the other end of the guide plate 9, the held portion of the ribbon 1 is at a predetermined angle (20°) with the top of the pedestal 2. 60°) and rest on the pedestal 2.

Next, the ultrasonic welding horn 3 descends, and as shown in FIG. 2, the overlapped ribbons 1 are pressed onto the pedestal 2 and at the same time, ultrasonic vibrations are applied to weld them. Since the guide plates 9a and 9b are inserted between the stacked ribbons 1, the ribbon 1 can be welded under tension by welding between the two guide plates 9a and 9b. Incidentally, either the ultrasonic welding horn 3 or the pedestal 2 may be provided with a top, or the top may be provided in the direction of the clamping device 5 so that the width of the surfaces in contact with both coincides with the width of the welding line. Welding can also be achieved by devising techniques such as shifting their positions.

When welding is completed and the ultrasonic welding horn 3 rises to its original position, the clamp device 5 automatically starts moving along the guide rail 8, and the ribbon 1 moves from one end of the guide plate 9 to the other end. Move at a constant speed. As the ribbon 1 moves, one edge 1 of the guide plate 9
0 gradually approaches the weld line 4 of the ribbon 1, and when the ribbon 1 reaches the guide groove 13, the weld line 4 of the ribbon 1
enters the guide groove 13, as shown in FIG.
The protruding edges 10 of the guide plates 9a and 9b touch both ends of the weld line 4 as they move further. Note that by forming the clamp head 6 of the clamp device 5 with elastic rubber, the moving ribbon 1 can be guided by the guide plate 9.
It is possible to alleviate the mechanical strain received from the

As shown in FIGS. 2 and 3, the guide plates 9a and 9b are vertically spaced apart by a distance approximately equal to the thickness of the ribbon 1, so that the portion that becomes the endless ribbon does not deform irregularly or become unreasonably strained. I never receive it.

As shown in FIG. 3, when the moving ribbon 1 approaches the laser head 15, the laser oscillator is activated, and the laser head 15a provided above one guide plate 9a opens the guide groove 13 of the other guide plate 9b. A laser beam (arrow) is irradiated onto the protruding slope 12 of the guide plate 9b, and conversely, the laser beam from the laser head 15b below the other guide plate 9b is irradiated onto the slope 12 of the guide plate 9a.
2. As a result, the remaining end 1c of the ribbon 1
is precisely cut at the welding line that is accurately positioned in the guide groove 13, and the laser beam that has cut the remaining end 1c is blocked by the inclined surface 12 of the guide plate 9. The irradiation angle of the laser beam is preferably as close to parallel as possible to the longitudinal direction of the ribbon 1, but since it is mechanically difficult, it is usually parallel to the longitudinal direction of the ribbon 1.
Around 30° is sufficient. However, if this angle exceeds 45°, there will be a large amount of unnecessary parts remaining near the weld line, and when the weld line is later flattened by ultrasonic welding, the width of the weld line will become larger than necessary, which is not preferable.
In addition, when cutting with a conventional knife, when tension is applied to the ribbon, the warp threads tend to come off, leaving the weft threads behind, but with laser cutting, the cut part melts and becomes a single piece, so the warp threads do not come off, making it highly accurate. It has the advantage of fast cutting speed.

Thereafter, the clamping device 5 moves in the opposite direction toward the pedestal 2 while holding the endlessly formed ribbon 1 and its remaining end 1c, and stops at the original position. Since the removed portion of the remaining end 1c cannot be said to be completely smooth, it is usually reshaped by ultrasonic welding. This shaping can be done by automatically replacing the pedestal 2 with a shaping pedestal with a wider top on the spot and lowering the ultrasonic welding horn 3 to apply ultrasonic vibrations. The ribbon may be removed from the clamp device 5 and shaped using a separately provided ultrasonic shaping horn and cradle.

An example of the endless ribbon manufacturing conditions with a ribbon width of 12 mm is shown below: Ultrasonic welding conditions: Frequency: 28 KHz Horn amplitude: 25 μm Welding load: 25 Kg Oscillation time: 0.05 seconds Weld line width: 0.4 mm Laser cutting conditions: Type: CO ₂ laser (wavelength) 10.6μm) Output: 5W Cutting speed: 6m/min Shaping conditions: Frequency: 28KHz Horn amplitude: 25μm Welding load: 25Kg Oscillation time: 0.1 seconds Final weld line width: 0.6mm When comparing the tensile strength of endless ribbons manufactured under the above conditions, the ribbon itself Tensile strength of 19
In the case of ~20Kg, the conventional method of type A in Figure 4a had a weld line width of 1 mm and an average weight of 6.5Kg, whereas the product produced under the above conditions using the apparatus of the present invention had a weld line width of 0.6 mm and an average weight of 13Kg. A tensile strength of .

〔Effect of the invention〕

According to the present invention, the ribbon portion is held substantially on a flat surface between one side of the two guide plates, one edge is inserted up to the weld line, and the remaining end portion is held close to the weld line due to the inclined surface. Since it can be branched, the remaining end can be cut as short as possible using the guide plate as a base, and the width of the final weld line after shaping can be minimized.

In addition, a laser head is used as a cutting device,
When cutting with a laser beam, the cut parts are welded and integrated, so the warp threads do not fall out, the finish after shaping is clean, the cutting accuracy is high, and the cutting speed is fast.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the main parts of a specific example of the device of the present invention, FIG. 2 is a sectional view showing the ribbon when welded, and FIG. 3 is a sectional view showing the ribbon when the remaining end is removed. . 4a and 5a are perspective views of a conventional ribbon welding device, and FIGS. 4b and 5b are perspective views of a conventional ribbon welding device.
are sectional views of respective weld lines. 1... Ribbon, 1c... Extra end, 2... cradle, 3
...Ultrasonic welding horn, 4...Welding wire, 5...Clamp device, 7...Movable plate, 9, 9a, 9b...
Guide plate, 10...one edge, 11...tapered part,
12... Inclined surface, 13... Guide groove, 15... Laser head.

Claims (1)

[Scope of Claims] 1. A device for cutting off the remaining end of an endless ribbon which has both ends of the ribbon overlapped on the entire surface along the longitudinal direction and welded at a weld line crossing the longitudinal direction; Two flat band-shaped guide plates formed into blade shapes by sloped surfaces that gradually become thinner from one side to the other, and two guide plates facing each other with one edge parallel to each other and spaced apart, A support stand supported at one end with its sloped surfaces located on opposite sides, one side of both guide plates parallel to each other, and planes including one side of each guide plate brought close to each other, and a support stand that is supported at one end, and a support stand that faces each of the sloped surfaces of the two guide plates. Two cutting devices are installed on both sides of the two guide plates and are movable together along one parallel edge of the guide plates.
An endless ribbon end cutting device comprising: a clamping device; 2. The endless ribbon residual end cutting device according to claim 1, wherein the cutting device is a laser cutting device. 3. Cutting off the remaining end of the endless ribbon according to claim 1 or 2, characterized in that there is a gap equal to the thickness of the ribbon between the planes including one side of each of the two guide plates. Device. 4. The endless ribbon surplus according to any one of claims 1 to 3, characterized in that the distance between the parallel opposing edges of the two guide plates is equal to the width of the weld line of the ribbon. End cutting device.