JPH028449B2 - - Google Patents

Description

[Detailed Description of the Invention] Field of the Invention The present invention is applied to a process for manufacturing rolled ceramic electronic components such as capacitors obtained by firing rolled ceramic green sheets. The present invention relates to a method and apparatus for winding ceramic green sheets onto the circumferential surface of a core.

Description of Prior Art As wound type ceramic electronic components, for example, capacitors, coils, etc. have been proposed and put into practical use.

FIG. 1 is a perspective view showing a wound-type ceramic capacitor as an example of a wound-type ceramic electronic component in a completed state of winding. FIG. 2 is a sectional view taken along line - in FIG. 1.

In general, wound-type ceramic electronic components, including the wound-type ceramic capacitor shown here, have a ceramic green sheet 2 wound around the outer peripheral surface of a rod-shaped core 1, and sheet layers constituting each circumference are laminated. Take. At this time, depending on the conductive pattern formed on the ceramic green sheet 2,
Various electronic components can be obtained.

As shown in FIG. 2, when obtaining a capacitor, the conductive portions formed on the ceramic green sheet 2 will constitute the first and second internal electrodes 3, 4, respectively. A capacitance is formed between the first internal electrode 3 and the second internal electrode 4. Although not shown, external electrodes are formed on both end surfaces of the structure shown in FIG. 2, one of which is electrically connected to the first internal electrode 3, and the other external electrode is connected to the second internal electrode. 4 and is brought into electrical continuity. In order to obtain the first and second internal electrodes 3, 4 as shown in FIG. 2, two types of methods are typically considered.

Figures 3 and 4 show the first method of forming internal electrodes.
FIG. 2 is a plan view of a ceramic green sheet for explaining an example. In this example, two ceramic green sheets 2a and 2b are used. A first internal electrode 3 is formed on one surface of one ceramic green sheet 2a, and a second internal electrode 3 is formed on one surface of the other ceramic green sheet 2b.
Internal electrodes 4 are formed. The first internal electrode 3 formed on one ceramic green sheet 2a is
On one surface of the ceramic green sheet 2a, margins are left at the starting end 5, right edge 6, and end 7, respectively. The second internal electrode 4 formed on the other ceramic green sheet 2b is formed on one surface of the ceramic green sheet 2b, leaving margins at the starting end 8, left edge 9, and terminal end 10, respectively. And both ceramic green sheets 2a,
When the electrodes 2b are stacked and rolled up in the direction shown in the drawing, an internal electrode formation state as shown in FIG. 2 is obtained.

FIG. 5 is a plan view of a ceramic green sheet illustrating a second example of the internal electrode forming method. In this second example, only one ceramic green sheet 2 is used. On one surface of the ceramic green sheet 2, a plurality of first internal electrodes 3 and a plurality of second internal electrodes 4 are arranged alternately in the length direction of the ceramic green sheet 2 with an insulating gap 11 in between. Each first internal electrode 3
is formed such that its left side edge extends to the left side edge of the ceramic green sheet 2, and its right side edge leaves a predetermined margin 12 at the right side edge of the ceramic green sheet 2. Each of the second internal electrodes 4 has a left edge formed of a ceramic green sheet 2.
A predetermined margin 13 is left on the left side edge of the ceramic green sheet 2, and the right side edge thereof extends to the right side edge of the ceramic green sheet 2. 1 like this
Using a ceramic green sheet 2, it is rolled up to form a first internal electrode 3 as shown in FIG.
When forming a capacitor with the second internal electrode 4, the sixth
As shown in the figure, the first internal electrode 3 and the second internal electrode
In order to efficiently obtain a large capacity, it is preferable that the internal electrode 4 be opposed to the ceramic green sheet 2 over approximately one circumference. For this purpose, lengthwise dimensions L1 and L of each internal electrode 3 and 4 are required.
2,..., Ln are preferably made sequentially longer from the inner circumferential side to the outer circumferential side as shown in FIG.

FIG. 7 is a plan view showing a state in which a conductive portion is formed in a ceramic green sheet used for manufacturing a wound ceramic coil as another example of a wound ceramic electronic component. The left and right side edges of the ceramic green sheet 2 shown here are marked with
Extracting electrodes 14 and 15 are formed to achieve electrical connection with external electrodes (not shown). and,
When the ceramic green sheet 2 is rolled up, a conductive portion 16 serving as a spiral conductive path extends diagonally and is electrically connected to both lead electrodes 14 and 15. The ceramic green sheet 2 shown in FIG. 7 is also rolled up as shown in FIG. 1, thereby forming a coil.

FIG. 8 is a diagram illustrating a conventional winding method. Conventionally, when winding the ceramic green sheet 2 onto the circumferential surface of the core 1, the upper and lower two flat plates 17, 18 are relatively moved in the direction shown by the arrow 19, and the two flat plates 17, 18 The core 1 and the rolled portion of the ceramic green sheet 2 in contact with the core 1 are rolled while applying an appropriate pressure. In addition, when using the two ceramic green sheets 2a and 2b shown in FIGS. The winding is performed. however,
According to this winding method, the rolled portion never becomes a perfect circle. This is because the ceramic green sheet 2 used in such rolled-up ceramic electronic components is required to be flexible in the bending direction, and the upper and lower flat plates 1
7 and 18, this flexibility results in an ellipse extending laterally. That is, it takes the form of an ellipse as shown by the broken line in FIG. This creates a gap between the layers of the ceramic green sheets 2 located on both sides of the core 1. Therefore, this gap will remain even after the subsequent firing process.

When electronic components are manufactured using a ceramic body with residual gaps as described above, structural defects such as delamination occur and moisture resistance properties deteriorate. Also, especially in the case of capacitors,
The presence of gaps leads to a decrease in capacitance, which also leads to variations in capacitance between products.

In addition, in the winding method as shown in Fig. 8, arrow 1
It is expected that it will be difficult to maintain orthogonality between the nine directions and the axial direction of the core 1. Therefore,
The ceramic green sheet 2 rolled up on the circumferential surface of the core 1 gradually shifts in the axial direction of the core 1, and the end surface of the rolled ceramic green sheet 2 often becomes a conical surface instead of a flat surface. . If this kind of entanglement occurs, it may cause variations in the obtained ceramic electronic components between products, or it may interfere with the formation of external electrodes, and especially in the case of capacitors, the internal electrodes may not be in an appropriate facing state. Encounter problems such as becoming confused.

OBJECTS OF THE INVENTION Therefore, an object of the present invention is to provide a winding method and apparatus that can roll up ceramic green sheets without gaps.

Another object of the present invention is to provide a winding method and apparatus capable of winding a ceramic green sheet with its both sides properly aligned.

Summary of the Invention The method of the present invention is characterized in that a belt is used to wind up the ceramic green sheet. This belt is passed between a pair of guide surfaces with a portion of the belt bent.
An annular portion is formed that projects from between the pair of guide surfaces. The pair of guide surfaces face each other and extend in parallel with a predetermined interval. One end of the ceramic green sheet is inserted into the inner space of the ring-shaped portion. A core is placed on one side of one end of the ceramic green sheet. The arrangement of the core is selected such that the axial direction of the core coincides with the width direction of the belt.
In this state, when the belt moves relative to the pair of guide surfaces, the ceramic green sheet can be rolled up on the circumferential surface of the core within the looped portion. That is, the outer circumferential surface of the annular portion is in contact with both of the pair of guide surfaces, and the inner circumferential surface of the annular portion is in contact with a part of the outer circumferential surface of the core and the other surface of one end of the ceramic green sheet. It is considered to be in contact. The distance between the pair of guide surfaces is set so that even if tension is applied to the belt, the core passes between the pair of guide surfaces and the looped portion does not unravel. Under these conditions, when relative movement of the belt occurs, the ceramic green sheet is moved within the ring by rotating the core around its axis within the ring as the belt moves. The other surface of the ceramic green sheet is brought into contact with the inner peripheral surface of the annular portion, and the ceramic green sheet is wound onto the outer peripheral surface of the core. Finally, the ceramic green sheet rolled onto the core is taken out from the loop-shaped portion, and a ceramic green sheet having a desired rolled shape is obtained.

The device of the invention advantageously implements the winding method as described above, in which the belt is driven in the direction of its length. The guide rods constituting the pair of guide surfaces described above are located on one side of the belt, extend in the width direction of the belt, and are spaced apart from each other. This pair of guide rods is configured so that the distance between them can be changed. The means for forming the above-mentioned loop-like portion is constituted by, for example, a rotatably provided arm and a protrusion member attached to the end of the arm, and the means for forming the loop-shaped portion protrudes from the other side of the belt. The pressing of the members causes an annular portion to be formed. In order to insert a ceramic green sheet into such an annular portion, a table for holding the ceramic green sheet with its end protruding, and a means for moving this table toward the annular portion are provided. is provided. Means for feeding the core to one side of the ceramic green sheet in the inner space of the loop-shaped portion is provided, and a winding device is achieved.

DESCRIPTION OF EMBODIMENTS The objects and features of the present invention will become clearer from the following description of embodiments with reference to the drawings.

The following examples relate, by way of example, to the manufacture of wound ceramic capacitors.

FIG. 9 is a plan view showing a more practical state of forming internal electrodes on a ceramic green sheet used in manufacturing a wound type ceramic capacitor.
FIG. 10 shows a state in which the ceramic green sheet of FIG. 9 is wound around the circumferential surface of the core. The ceramic green sheet 20 shown in FIG.
When cut along 1, the ceramic green sheet 2 has substantially the same internal electrode pattern as the ceramic green sheet 2 shown in FIG. That is, the conductive portion 2 formed on the ceramic green sheet 20
2, some become the first internal electrode 3 in FIG. 5, some become the second internal electrode 4, and in some cases, each side of the half portion cut along the cutting line 21 is First or second internal electrode 3
Or 4. If the electrode formation pattern shown in FIG. 9 is adopted, winding for a plurality of capacitors can be performed simultaneously by winding the ceramic green sheet 20 once. That is, as shown in FIG. 10, after the ceramic green sheet 20 is wound around the circumferential surface of the core 23, cutting along the cutting line 21 is performed.

The ceramic green sheet 20 is formed into a sheet by kneading ceramic powder material with a thermoplastic resin such as polyvinyl butyral or vinyl acetate as a binder.

Hereinafter, a method and apparatus for rolling up the ceramic green sheet 20 shown in FIG. 9 as shown in FIG. 10 will be explained.

FIGS. 11 to 17 show an embodiment of the method of the present invention in the order of steps.

Referring to FIG. 11, belt 24 is prepared,
A pair of upper and lower guide rods 25 and 26 are placed in contact with one side of the belt 24 and spaced apart from each other. The guide bars 25, 26 both extend in the width direction of the belt and are therefore parallel to each other. Note that the guide rods 25 and 26 may be arranged at positions slightly apart from one side of the belt 24.

Referring to FIG. 12, an arm 28 is provided on the other side of the belt 24 so as to be rotatable about a shaft 27. As shown in FIG. A curved protruding member 29 is attached to the end of this arm 28 . When the arm 28 rotates and the protruding member 29 pushes the other side of the belt 24, the belt 24 is bent between the pair of guide bars 25, 26, and the belt 24 is bent between the pair of guide bars 25, 26.
6, a protruding ring-shaped portion 30 is formed. After the formation of the annular portion 30, the arm 28 is rotated in the opposite direction and the protruding member 29 is withdrawn from the annular portion 30.

Referring to FIG. 13, a ceramic green sheet 20 is held by a holding stand 31, and its end portion is inserted into a ring-shaped portion 30. It is preferable that the ceramic green sheet 20 is held on the holding table 31 with its end portions protruding.

Referring to FIG. 14, a core 23 is supplied onto the ceramic green sheet 20 as shown by the dotted line, and then carried along the top surface of the ceramic green sheet 20 to a position shown by the solid line. At least at the stage shown in FIG. 14, the pair of guide rods 25 and 26 are spaced apart enough to allow the movement of the core 23 as described above.
In FIG. 14, the core 23 is located within the inner space of the annular portion 30 and is located inside the ceramic green sheet 2.
0, and its axial direction coincides with the width direction of the belt 24.

Referring to FIG. 15, a pair of guide rods 25, 2
The interval between 6 is narrowed. Accordingly, the core 23
is a pair of guide rods 25, 2 from the ring-shaped portion 30.
It is said to be in a state where it does not pass through 6 intervals.

When tension is applied to the belt 24 in the state shown in FIG.
A part of the outer peripheral surface of the ceramic green sheet 20
The inner circumferential surface of the annular portion 30 is in reliable contact with the lower surface of one end of the annular portion 30. In this state, when the belt 24 is moved in the direction of the arrow 32, as shown in FIG. The core 23 will rotate about its axis within the annular portion 30, thereby drawing the ceramic green sheet 20 into the annular portion 30. Accordingly, the ceramic green sheet 20 is rolled onto the outer peripheral surface of the core 23 while the outwardly facing surface of the ceramic green sheet 20 is in contact with the inner peripheral surface of the ring-shaped portion 30. In such a winding process, it is preferable that the distance between the pair of guide rods 25 and 26 be as narrow as possible. This is because the force applied from the outside to the core 23 and the ceramic green sheet 20 during the winding process is distributed over a range closer to the entire circumference, thereby making it possible to obtain a tighter winding state. This is because it is possible.

In the explanation of FIG. 16, it was stated that the belt 24 is moved in the direction of the arrow 32, but this movement may be relative to the guide rods 25 and 26, and the belt 24 may be fixed while being fixed. A pair of guide rods 25 and 26 may be moved.

Referring to FIG. 16, preferably, in the final stage of rolling up the ceramic green sheet 20, the heater 33 is brought into contact with the outer peripheral surface of the annular portion 30. The heater 33 is heated to, for example, 140 to 150°C, and the ceramic green sheet 2
0, which binds at least the ends of the roll of the ceramic green sheet 20 and prevents the ceramic green sheet 20 from undesirably unraveling after the roll.

Referring to FIG. 17, a pair of guide rods 25, 26
The gap between the belts 24 is widened, and tension is applied to the belt 24 in this state. Accordingly, the annular portion 30 shown in dotted lines in FIG.
It passes between 5 and 26 and finally disappears. According to the movement of the ring-shaped portion 30, the ceramic green sheet 20 and the core 23 pass between the pair of guide rods 25 and 26, and are finally brought to the position shown by the solid line in FIG. , from here it falls downward. In this way, the ceramic green sheet 20 that has been completely rolled up is taken out.

Thereafter, the steps sequentially shown in FIGS. 11 to 17 are repeated.

FIG. 18 is a perspective view showing the arrangement of elements included in one embodiment of the device of the present invention. In FIG. 18, the ceramic green sheet 20, core 23, belt 24, guide rods 25, 26, shaft 27, arm 28, protruding member 29, ring-shaped portion 30, and holding stand shown in FIGS. 11 to 17 are shown. 31, and heater 33 are shown with the same reference numerals. Below, this figure 18 and figures 19 to 24 will be explained.
The details of each part will be explained with reference to each drawing in the figure.

FIG. 19 schematically shows the belt 24 and belt drive mechanism of the apparatus of FIG. 18. In the embodiment now being described, the belt 24 is ended. Each end of the belt 24 is wound around an upper reel 34 and a lower reel 35, which are rotatably supported. The upper reel 34 is rotationally driven by an upper motor 36 in a direction in which the belt 24 is wound. The lower reel 35 is rotationally driven by the lower motor 37 in the direction in which the belt 24 is wound.

FIG. 20 shows a cross-sectional structure of the upper reel 34 around which the belt 24 is wound. The upper reel 34 includes an outer sleeve 28 having a C-shaped cross section, and an inner rod 39 that fits into the inner peripheral surface of the outer sleeve 38. The inner rod 39 is formed with a radially projecting rib 40, which is located within the cutout of the outer sleeve 38. A compression spring 41 is disposed between the rib 40 and the outer sleeve 38, so that the outer sleeve 38 is constantly urged to rotate clockwise relative to the inner rod 39. A shaft (not shown) that rotatably supports the upper reel 34 is fixedly provided on the inner rod 39. The belt 24 has a compression spring 4
1 is inserted between the rib 40 and the outer sleeve 38 on the opposite side to the side where the sleeve 1 is disposed. As a result, the end of the belt 24 is fixed to the upper reel 34 by the action of the compression spring 41.

Although not particularly shown, a similar configuration is also adopted for the lower reel 35.

The upper reel 34 is preferably made of a metal material, and the stoppage of the lower motor 37 that drives the lower reel 35 is controlled using the conductivity of this material. That is, the switch contact 42 is provided so as to come into contact with the circumferential surface of the upper reel 34. The belt 24 is usually made of ceramic green sheet 20.
It is made of glass fiber coated with, for example, tetrafluoroethylene resin, taking into account the ease of peeling. That is, the belt 24 is insulating.
Therefore, when the belt 24 wound around the upper reel 34 runs out, the switch contact 42 contacts the metal upper reel 34 and becomes electrically conductive, and in response, the lower reel The lower motor 37 is controlled to stop so that the winding operation of the lower motor 35 is stopped.

In addition to the control mechanism as described above, control units 43 and 44 including limit switches, timers, etc.
They are provided to control rotation and stop of the motors 36 and 37, respectively.

FIG. 21 shows a mechanism for forming the loop portion 30 on the belt 24. As shown in FIG. The mechanism for forming the annular portion 30 includes an arm 28 rotatably supported by the aforementioned shaft 27 and a protruding member 2.
9, but such a protruding member 29
For rotation in the direction of arrow 45, a fluid cylinder 46 using air or oil as a driving source is used. The cylinder 46 is rotatably supported on a suitable fixed surface, and its plunger 47 is rotatably connected to a connecting rod 48 fixedly provided to the arm 28. Therefore, by actuating the cylinder 46, the protruding member 29 rotates in the direction of the arrow 45 about the shaft 27 via the plunger 47, the connecting rod 48, and the arm 28.

FIG. 22 shows a mechanism for changing the distance between the pair of guide rods 25, 26. Each guide rod 25,2
6 is preferably rotatably supported about axes 49,50. In order to change the distance between the pair of guide rods 25, 26, it is sufficient to fix one guide rod and make only the other guide rod movable. Therefore, in this embodiment, the upper guide rod 25 is provided so as to be movable. That is, the shaft 49 for the upper guide rod 25 is located at the fulcrum 51
The plunger 54 of the cylinder 53 is connected to the other end of the arm 52, which is rotatable around the center. Therefore, by actuating the cylinder 53, the arm 52 swings and the upper guide rod 25 can move between the position shown by the solid line and the position shown by the imaginary line. As a result, the distance between the pair of guide rods 25 and 26 is changed.

Figure 23 shows ceramic green sheet holding stand 3
1 and a core supply mechanism are schematically shown. The holding table 31 and related structures will be explained with reference to FIG. 23 and FIG. 18 described above.
As shown in FIG. 18, the holding stand 31 is
A stepped portion 55 is provided for positioning the ceramic green sheet 20. Therefore, by bringing one side of the ceramic green sheet 20 into contact with the stepped portion 55, the ceramic green sheet 20 is always properly positioned on the holding table 31. In this positioning state, one end of the ceramic green sheet 20 protrudes from the holding base 31.
The surface 56 of the holding base 31 that comes into contact with the ceramic green sheet 20 is covered with the ceramic green sheet 2.
A plurality of vacuum suction holes for vacuum suctioning 0 are formed. Note that this vacuum suction hole is not shown in the drawings because it is a fairly fine hole.

A tailstock plate 57 is arranged below such a holding stand 31. On both sides of the tailstock plate 57, tailstock rods 58 extending beyond the upper surface of the holding base 31 are provided. This core push rod 58 is for transporting the core 23, as shown in FIG. 14 described above. Holding stand 31 and tailstock plate 57
are provided so as to be movable independently in the directions of arrows 59 and 60 in FIG. 18, and each movement is driven by a cylinder (not shown).

Referring to FIG. 23, a fixed bracket 62 is provided extending from a fixed wall 61. As shown in FIG. A first slide mechanism 63 is provided on this fixed bracket 62, and a tailstock plate 57 is attached thereon. The first slide mechanism 63 includes a lower stand 64 and an upper stand 65, and between the lower stand 64 and the upper stand 65,
A plurality of rollers 66 are arranged. Therefore,
The lower stand 64 and the upper stand 65 are relatively movable in a linear direction, and accordingly, the tailstock plate 57 moves in the direction of arrows 59 and 60 (the first
(Fig. 8).

A second slide mechanism 67 having the same configuration as the first slide mechanism 63 is also arranged on the tailstock plate 57, and the holding base 31 is placed on it.

FIG. 24 schematically shows a mechanism for dispensing the cores 23 one by one. This figure 24 is shown in figure 18.
The feeding mechanism for the core 23 will be described with reference to the drawings and FIG. 23.

A plurality of leads 23 to be supplied are arranged in the vertical direction and stored in the lead storage container 68. The bottom of the lead storage container 68 forms an opening, and this opening is connected to the pusher plate 6 to prevent the lead 23 from falling out.
It is closed by 9. Pushya plate 6
9 is provided so as to be movable in directions of arrows 71 and 72 by actuation of a cylinder 70. A groove 73 is formed in the upper surface of the pusher plate 69 to receive the cores 23 one by one. In this way,
At the end of the movement of the pusher plate 69 in the direction of the arrow 72, one core 23 is received in the groove 73,
By moving in the direction of arrow 71, such core 23 is carried to a predetermined position. Next, the pusher plate 69
The upper surface prevents the lead 23 from falling from the lead storage container 68.

The core 23 received in the groove 73 and carried to a predetermined position is attracted by the vacuum chuck 74. The vacuum chuck 74 attracts the core 23 received in the groove 73 and lifts it from its position,
Next, the ceramic green sheet 20 is moved laterally and carried above the ceramic green sheet 20 on the holding table 31, and is then displaced downward.
Along the path of dropping the core 23 onto 0,
It is provided so that it can be moved along the reverse of the route just described. More specifically, as shown in FIG.
Book rods 75 extend and are slidably retained through blocks 76. For example, two rods 77 extend downward from the block 76, and these rods 77 are slidably held in suitable fixing parts 78. Therefore, by applying a driving force to rods 75 and 77, vacuum chuck 74 moves as described above. Rod 75 and 77
For the purpose of driving, e.g. a cylinder (not shown)
is used.

Next, the operations of the above-mentioned specific apparatus will be sequentially explained.

First, in the preparation stage, the lower motor 37 is turned on and the belt 24 is wound onto the lower reel 35 side. When the switch contact 42 comes into electrical contact with the upper reel 34, the lower motor 37 is stopped. During this time, the upper motor 36 is in an off state. Further, the holding base 31 and the tailstock plate 57 are at the end position of movement in the direction of the arrow 60. The protruding member 29 is also kept at a distance from the belt 24. Further, the vacuum chuck 74 has one core 23.
While holding the button, it is placed on standby at a position above the pusher plate 69.

After the preparation process as described above is completed, regular winding work of the ceramic green sheet 20 is started. First, the cylinder 46 is actuated to rotate the protrusion member 29, and the loop-shaped portion 30 is formed on the belt 24. After the annular portion 30 is formed, the protruding member 29 is again moved away by the actuation of the cylinder 46. Next, when the ceramic green sheet 20 is placed on the holding table 31, vacuum suction is started on the surface 56 of the holding table 31, and the ceramic green sheet 20 is firmly held on the holding table 31. At the same time, the holding base 31 moves to the arrow 5.
Move in 9 directions and press Ceramic Green Sheet 2
0 into the inner space of the loop-shaped portion 30. Next, the vacuum chuck 74 moves and drops the core 23 onto the ceramic green sheet 20. Core 23
The vacuum chuck 74 that has dropped the wick 74 immediately returns to its original position and waits while adsorbing the wick 23 to be supplied next. In response to vacuum chuck 74 dropping core 23 onto ceramic green sheet 20, tailing plate 57 moves in the direction of arrow 59. At this time, the pair of tailing rods 58 carry the core 23 into the annular portion 30 while contacting both ends of the core 23. Even when carried within the ring-shaped portion 30, the core 23
It is placed on the top surface of the ceramic green sheet 20.

Next, the upper guide rod 25 moves downward to narrow the distance between the pair of guide rods 25 and 26. At the same time, the tailstock plate 57 is moved away in the direction of arrow 60.
At the same time, the upper motor 36 is turned on and the upper reel 34 is rotated. In response to this rotation, belt 24 moves upward along its length. Correspondingly, the ceramic green sheet 20 is rolled onto the core 23. When a predetermined period of time has elapsed since this winding was started, the holding table 31 moves to the direction indicated by the arrow 6
Retreat in direction 0. While the upper motor 36 is rotating, the lower motor 37 is off, and friction in the transmission mechanism from the lower motor 37 to the lower reel 35 provides an advantageous tension to the belt 24. After the upper motor 36 starts rotating and a certain period of time set by the timer has elapsed, the upper motor 36 is stopped through the control section 43. This time setting is determined depending on the length of the ceramic green sheet 20 to be rolled up. Further, at the final stage of rolling up the ceramic green sheet 20, the heater 33 is driven, for example, by a cylinder, and moves so as to come into contact with the outer peripheral surface of the annular portion 30. Accordingly, adhesion is achieved at least at the ends of the rolled ceramic green sheet 20.

When the winding is completed, the upper guide rod 25 moves upward, and the distance between the pair of guide rods 25 and 26 is widened. Then, the lower reel 35 rotates, and the belt 24 is wound onto the lower reel 35 side.
In response to this winding, the loop-shaped portion 30 passes between the pair of guide rods 25 and 26, causing the wound ceramic green sheet 20 to fall. This fallen ceramic green sheet 20 is stored in a storage box (FIG. 18).

Thereafter, the process starting from driving the protrusion member 29 described above is repeated, and one rolled ceramic green sheet 20 is produced each time one process cycle is completed.

The following modifications can be considered as the driving method for the belt 24. In the above embodiment, the upper reel 34 was rotated to wind up the belt 24, and after the winding of the ceramic green sheet 20 was completed, the lower reel 35 was rotated to rewind the belt 24 onto the lower reel 35. . In this case, as long as the belt 24 is long enough, the belt 4 may be unwound by the rotation of the lower reel 35 to the extent that the looped portion 30 is eliminated. Further, the upper reel 34 may be rotated in order to eliminate the loop-shaped portion 30. In this case, by only rotating the upper reel 34,
The winding cycle of a plurality of ceramic green sheets 20 is repeated, and the lower reel 35 is rotated for the first time when the belt 24 wound around the lower reel 35 is about to run out. All of the above-described driving methods for the belt 4 require driving the belt 24 in the reciprocating direction. however,
If the belt 24 is endless, the belt 24 may be driven in only one direction. endless belt 24
A schematic configuration when using the above is shown in imaginary lines in FIG. 19.

Referring to FIG. 19, when belt 24 is endless, upper reel 34 and lower reel 35 become mere rollers. Further, only the motor 36 that rotationally drives the upper roller 34 is required, and the motor 37 is not required. A tension roller 80 is added to provide the desired tension on the belt 24;
A belt 24 is hung here. Tension roller 80 is biased by spring 81 in a direction that applies tension to belt 24 . However, this tension roller 80 does not act on the belt 24 all the time, and the tension roller 80 does not act on the belt 24 at all times. Accordingly, the tension roller 80 is configured to be selectively brought into an operative state and a non-operative state.

FIGS. 25 and 26 each schematically show a mechanism for taking out the rolled ceramic green sheet 20 employed in another embodiment of the apparatus of the present invention. Other embodiments shown herein each include an orbicular portion 30 once formed.
However, consideration has been given to ensuring that the ceramic green sheet 20 is not lost due to removal. Therefore, in the subsequent process, the step of forming the ring-shaped portion 30 is omitted.

In FIG. 25, the core 23 has a length longer than the width of the ceramic green sheet 20, as shown in FIG.
The length is selected so that it protrudes from the end face of the belt 24 and also protrudes from both sides of the belt 24. Therefore, the take-out arms 83 provided on both sides of the belt 24 can directly contact the core 23. The take-out arm 83 is rotatably supported around a shaft 84 . To drive this rotation, the cylinder 85
The cylinder 85 is rotatably held at a suitable fixed part, and the plunger 86 of the cylinder 85 is
is connected to the take-out arm 83. In such a configuration, when the take-out arm 83 is rotated counterclockwise by the operation of the cylinder 85, the ceramic green sheet 20 is pushed out of the annular portion 30 via the core 23, and the annular portion 30 is pushed out through the core 23. remains and is maintained.

In FIG. 26, a case is shown in which the ceramic green sheet 20 within the ring-shaped portion 30 is pushed out in the axial direction of the core 23 and taken out. A push rod 87 for this purpose is connected to a plunger 89 of a cylinder 88 . When the cylinder 88 is actuated, the pushing rod 87 abuts against the end face of the core 23 and removes the ceramic green sheet 20 from the annular portion 30. Although the core 23 is shown by a dotted line in FIG. 26, this means that the length of the core 23 does not necessarily need to be longer than the width of the ceramic green sheet 20.

FIG. 27 shows the posture of the belt 24 and the method of inserting the ceramic green sheet 20 employed in yet another embodiment of the present invention. Here, belt 2
4 is run horizontally, and a pair of guide rods 25,
26 are arranged side by side. The annular portion 30 is formed to protrude downward.
When inserting the ceramic green sheet 20 into such an annular portion 30, it is inserted from above, and in order to maintain the proper posture of the ceramic green sheet 20, the ceramic green sheet 20 is
For example, it is held by a vacuum suction device 90. The core 23 is a ceramic green sheet 2 like this.
It is dropped on one side of 0. The principle of rolling the ceramic green sheet 20 onto the core 23 is the same as in the embodiment described above.

In connection with the embodiment of FIG. 27, the running direction of the belt 24 may be neither horizontal nor vertical, but may be in an inclined direction in between.

The rolled ceramic green sheet obtained as described above is, if necessary, rolled up using a method such as pressurizing it in a liquid while having a core, and then fired to form an electronic component or an electronic component. It becomes the element for. In addition to the capacitor, the target electronic component may be a coil, a ceramic heater, or other wound-type ceramic electronic component.

The core used for winding the ceramic green sheet becomes unnecessary once the winding is completed. Therefore, it is usually extracted after being rolled up. Possible materials for the core include metal, plastic, and ceramic. Note that when ceramic is used as the material for the core, firing may be performed with the core remaining. In the case of this ceramic, it may be a fired ceramic or a raw ceramic before firing.

Further, the present invention provides two ceramic green sheets 2a and 2 as shown in FIGS. 3 and 4.
It can also be applied to cases where b is rolled in at the same time. In this case, two ceramic green sheets may be stacked in advance and loaded into the apparatus.

Effects of the Invention According to the present invention, the ceramic green sheet can be rolled up using a belt while applying a pressing force toward the center in a range close to the entire circumference, so that the rolled-up state is extremely tight and uniform. can be obtained. Therefore, after firing, structural defects such as delamination and deterioration of moisture resistance properties do not occur. Moreover, especially when applied to a capacitor, variations in capacitance are prevented.

Furthermore, according to the method of the present invention, the ceramic green sheet is first positioned with respect to the belt and then the core is supplied, so that as long as the ceramic green sheet is precisely positioned with respect to the belt, proper winding with aligned end surfaces can be achieved. It becomes possible to include In other words, it is easy to position the ceramic green sheet alone, and even if the core supplied later is misaligned with the width direction of the ceramic green sheet, the core can be easily positioned in the next process of applying tension to the belt. This is because they are forced into an aligned state.

Furthermore, according to the device of the present invention, it is possible to automatically supply ceramic green sheets and cores.
Increased productivity.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing a wound-type ceramic capacitor as an example of a wound-type ceramic electronic component in a completed state of winding. FIG. 2 is a sectional view taken along line - in FIG. 1. 3 and 4 are plan views showing the internal electrode formation state applied to the first example of the ceramic green sheet used for manufacturing the capacitor shown in FIG. 1. FIG. Figure 5 is the first
FIG. 6 is a plan view showing a state of forming internal electrodes applied to a second example of the ceramic green sheet used for manufacturing the capacitor shown in the figure. FIG. 6 is a sectional view taken along the line - of FIG. 1 in the example of FIG.
FIG. 7 is a plan view showing a state in which a conductive portion is formed in a ceramic green sheet used for manufacturing a wound ceramic coil as another example of a wound ceramic electronic component. FIG. 8 is a diagram illustrating a conventional winding method. FIG. 9 is a plan view showing a more practical state of forming internal electrodes on a ceramic green sheet used in manufacturing a wound type ceramic capacitor. FIG. 10 shows a state in which the ceramic green sheet of FIG. 9 is wound around the circumferential surface of the core. FIGS. 11 to 17 show an embodiment of the method of the present invention in the order of steps. 18th
The figure is a perspective view showing the arrangement of elements included in an embodiment of the device of the present invention. FIG. 19 schematically shows the belt 24 and belt drive mechanism of the apparatus of FIG. 18. FIG. 20 shows a cross-sectional structure of the upper reel 34 around which the belt 24 is wound. FIG. 21 shows a mechanism for forming the loop portion 30 on the belt 24. As shown in FIG. FIG. 22 shows a mechanism for changing the distance between the pair of guide rods 25, 26. FIG. 23 schematically shows the ceramic green sheet holding stand 31 and the core supply mechanism. FIG. 24 schematically shows a mechanism for dispensing the leads one by one. FIGS. 25 and 26 each schematically show a mechanism for taking out the rolled ceramic green sheet 20 employed in another embodiment of the apparatus of the present invention. FIG. 27 shows the posture of the belt 24 and the method of inserting the ceramic green sheet 20 employed in yet another embodiment of the present invention. In the figure, 20 is a ceramic green sheet, 23 is a core, 24 is a belt, 25, 26 are guide rods, 29 is a protruding member, 30 is a ring-shaped portion, 3
1 is a holding stand, 34 is an upper reel, 35 is a lower reel,
36, 37 are motors, 46, 53 are cylinders, 5
2 is an arm, 57 is a tailstock plate, 58 is a tailstock, and 74 is a vacuum chuck.

Claims (1)

[Claims] 1. In a method of winding a ceramic green sheet onto the circumferential surface of a core, which is one process for manufacturing rolled-up ceramic electronic components, a part of the belt is bent and then pass between a pair of guide surfaces facing each other and extending parallel to each other at a predetermined interval to form a ring-shaped portion protruding from between the pair of guide surfaces, and in an inner space of the ring-shaped portion. Inserting one end of the ceramic green sheet, arranging the core on one side of the ceramic green sheet within the inner space of the annular portion so that its axial direction coincides with the width direction of the belt; a distance between the pair of guide surfaces is set so that the core passes through between the pair of guide surfaces and the ring-like portion does not unravel even if tension is applied to the belt; The ceramic green sheet is moved in the longitudinal direction relative to the pair of guide surfaces, and as the belt moves, the core is rotated around its axis within the annular portion. While drawing the ceramic green sheet into the ring-shaped part and bringing the other side of the ceramic green sheet into contact with the inner peripheral surface of the ring-shaped part, the ceramic green sheet is rolled onto the outer peripheral surface of the core, and the ceramic green sheet is rolled onto the core. A method for rolling up a rolled-up type ceramic electronic component, comprising the steps of taking out a ceramic green sheet from the ring-shaped portion. 2. The winding method according to claim 1, wherein the step of forming the ring-shaped portion is always carried out before starting other steps. 3. The step of taking out the wound ceramic green sheet includes the step of widening the distance between the pair of guide surfaces and applying tension to the belt to eliminate the loop-shaped portion.
The wrapping method described in section. 4. The winding method according to claim 1, wherein after the step of forming the ring-shaped portion is performed once, other steps are repeated multiple times. 5. The winding method according to claim 4, wherein the step of taking out the rolled ceramic green sheet is performed while the ring-shaped portion is maintained. 6. A device for winding a ceramic green sheet onto the circumferential surface of a core, which is used in one process for manufacturing rolled-up ceramic electronic components, comprising: a belt; means for driving the belt in the longitudinal direction; and the belt. 1 located on one side of the belt, extending in the width direction of the belt, and spaced apart from each other.
a pair of guide rods; means for changing the distance between the pair of guide rods; and bending a portion of the belt located at a position corresponding to the distance between the pair of guide rods. through,
means for forming an annular portion protruding from between a pair of guide rods so that the one surface of the belt is a circumferential surface facing outward; and a ceramic green sheet with its end portion protruding. a stand for holding the ceramic green sheet; means for moving the stand in order to insert the end of the ceramic green sheet from the other side of the belt into the loop-shaped portion; A winding device for winding-type ceramic electronic components, comprising means for feeding a core to one side of a ceramic green sheet. 7. The winding device according to claim 6, wherein the belt has an end. 8. The winding device according to claim 6, wherein the belt is endless. 9. The winding device according to claim 7, wherein each end of the belt is wound around a reel, and the means for driving the belt includes a motor that rotates the reel. 10. The winding device according to any one of claims 6 to 9, wherein each of the guide rods is held rotatably about its axis. 11. The winding according to any one of claims 6 to 10, wherein the means for changing the distance between the pair of guide rods includes a fluid cylinder for displacing at least one guide rod. Device. 12. The means for forming the ring-shaped portion includes:
comprising a rotatably provided arm and a protrusion member attached to an end of the arm, and the ring-shaped portion is formed by the protrusion member pushing the other side of the belt; A winding device according to any one of claims 6 to 11. 13. The winding device according to any one of claims 6 to 12, wherein the stand includes a stepped portion for positioning the ceramic green sheet. 14. The winding device according to any one of claims 6 to 13, wherein the stand is provided with a plurality of vacuum suction holes on the surface that contacts the ceramic green sheet. 15. The winding device according to any one of claims 6 to 14, wherein the means for moving the table includes a fluid cylinder. 16 The means for supplying the core comprises means for dropping the core onto the ceramic green sheet, and means for transporting the dropped core along the ceramic green sheet to the inner space of the annular portion. A winding device according to any one of claims 6 to 15.