JP3648890B2 - Printing apparatus and printing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a printing instrument and a printing method that can easily print the inner surface of a circular tube or the like by transfer printing.
[0002]
[Prior art]
For example, Japanese Patent Application Laid-Open No. Hei 6-275221 discloses that an electron beam lens system provided in a neck portion of a cathode ray tube is configured by printing a plurality of grids on the inner surface of a cylindrical substrate. As a conventional method for printing on the inner surface of a circular tube such as a cylindrical substrate in this case, a dispenser method is well known and described in the publication. In this dispenser method, a nozzle connected to an ink tank is inserted into the inner surface of the circular tube, and ink is ejected from the nozzle and applied to the inner surface of the circular tube. An ink jet method is also known in which ink is ejected from a pipe having a large number of holes instead of a nozzle.
[0003]
Further, the publication also discloses a method of printing a conductive pattern on the inner surface of the cylindrical substrate by a transfer method by rolling a rubber roller having a conductive paste as ink on the surface along the inner peripheral surface of the cylindrical substrate. Has been.
[0004]
[Problems to be solved by the invention]
The above-described dispenser method basically draws patterns one by one, and has a drawback that it takes a relatively long drawing time. The same applies to the ink jet method, but in the so-called direct drawing method in which ink is drawn directly on the inner surface of the tube for drawing, a fine pattern is printed on the inner surface of the tube with a small inner diameter, such as the above-mentioned cylindrical base for a cathode ray tube. In this case, it is necessary to use small nozzles and pipe ejection holes, and there is a problem that ink is easily clogged in the ejection holes.
[0005]
In the case of printing by the transfer method using the rubber roller disclosed in the above publication, the above problems do not occur. However, the transfer method by rolling of the rubber roller has a problem that only a relatively simple pattern can be printed.
[0006]
Accordingly, an object of the present invention is to enable printing on the inner surface of a circular tube or the like in a short time, and to easily and reliably print a fine and relatively complicated pattern on the inner surface of a circular tube or the like having a small inner diameter. It is to provide a printing apparatus and a printing method that can perform printing.
[0007]
[Means for Solving the Problems]
The printing device of the present invention that solves the above-described problem is configured to cover the holding member having a pressurized fluid blowing hole on the outer peripheral surface and the outer peripheral surface of the holding member so as to be separated from each other, and pressurize the pressurized fluid. A transfer pad that expands and contracts when the pressure is released and returns to its original state And with , At the position of the blowing hole, the transfer pad Film thickness Relating to printing equipment characterized by being relatively small .
[0008]
In one aspect of the present invention, the holding member has a rod shape, and the film thickness of the transfer pad changes in the longitudinal direction of the holding member.
[0010]
In one aspect of the present invention, the film thickness at the center of the transfer pad is smaller than the film thickness at both ends.
[0011]
In one embodiment of the present invention, the film thickness decreases from one end of the transfer pad to the other end.
[0012]
In one embodiment of the present invention, the thickness of the transfer pad changes continuously.
[0013]
In one embodiment of the present invention, the thickness of the transfer pad changes stepwise.
[0014]
In one aspect of the present invention, the blowing hole is provided around one place in the longitudinal direction of the holding member.
[0015]
In one aspect of the present invention, the blowing holes are provided around a plurality of locations in the longitudinal direction of the holding member.
[0016]
In one aspect of the present invention, the outer peripheral surface of the holding member is configured to have a shape corresponding to a change in the film thickness of the transfer pad.
[0017]
In one aspect of the present invention, the outer peripheral surface of the transfer pad is substantially in the same cylindrical surface.
[0018]
Further, in the printing method of the present invention, the holding member having a pressurized fluid blowing hole on the outer peripheral surface, and the outer peripheral surface of the holding member are coated so as to be separated from each other, At the position of the blowing hole Film thickness Relatively small A printing tool provided with a transfer pad is opposed to the printing surface, and the transfer pad is expanded by pressurization of the pressurized fluid to be brought into contact with the printing surface and previously attached to the outer peripheral surface of the transfer pad. Ink is transferred to the printing surface.
[0019]
In one aspect of the present invention, the printing surface is a curved surface.
[0020]
In one aspect of the present invention, the holding member has a rod shape, and the printing surface is an inner surface of a hole provided in the printing medium.
[0021]
In one aspect of the present invention, the transfer pad sequentially contacts the inner surface of the hole sequentially from the center to both ends.
[0022]
In one aspect of the present invention, the transfer pad sequentially contacts the inner surface of the hole sequentially from one end to the other end.
[0023]
One embodiment of the present invention is applied when a conductive pattern is formed on the inner peripheral surface of a cylindrical part or cylindrical portion.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described according to preferred embodiments.
[0025]
First, with reference to FIG.3 and FIG.4, the to-be-printed body (work | work) used as an example in the following embodiment is demonstrated.
[0026]
As shown in FIG. 3, the printed material (work) exemplified in the embodiment of the present invention is provided at the neck portion of the cathode ray tube 100 as disclosed in the above-mentioned Japanese Patent Laid-Open No. 6-275221. This is a high resistance tube 110 constituting the main lens system of the electron beam. In FIG. 3, the components other than the high resistance tube 110 in the cathode ray tube 100 are not shown.
[0027]
As shown in FIGS. 3 and 4, the high resistance tube 110 is made of, for example, alumina (Al ₂ O _Three ) Insulating materials with high pressure resistance, consisting of materials made conductive by mixing and sintering oxides such as Ti, W, Cu, etc., and ferrite, titania ceramics, etc. made conductive The main component. The high resistance tube 110 is formed in a cylindrical shape having a high roundness (for example, 20 μm or less), and, for example, RuO is formed at both ends and the center thereof. ₂ -Ring-shaped electrode films 111, 112, 113 made of glass paste (trade name # 9516, manufactured by DuPont, etc.) are formed by coating. In addition, a ring-shaped conductive ring 114 made of the same material is formed between the electrode films 111 to 113. Here, the electrode films 111 and 113 are electrically connected to the outside from both ends of the high resistance tube 110, respectively, and the third grid (G _Three ) And the fifth grid (G _Five ) Respectively. The electrode film 112 is electrically connected to the outside through a through-hole (not shown) formed in the wall portion of the high resistance tube 110, and the fourth grid (G of the main lens system of the electron beam). _Four ). The conductive ring 114 formed between the electrode films 111 to 113 has a potential fixed through the conductive inner wall of the high resistance tube 110, stabilizes the potential in the radial direction in the high resistance tube 110, and the electrode films 111 to 113. The following shows effects such as relaxation of the potential gradient between them, reduction of spherical aberration by fine adjustment of the potential between the electrode films 111 to 113, and stabilization of the potential between the electrode films 111 to 113.
[0028]
Thus, the main lens system G of the electron lens of the cathode ray tube _Three ~ G _Five Is composed of a conductive pattern coated and formed in the high resistance tube 110, thereby the main lens system G _Three ~ G _Five Improves concentricity. As a result, the axial deviation of the electron beam can be reduced, and a high-quality image can be realized. In addition, since the potential gradient between the electrodes constituting the main lens system is reduced, discharge between the electrodes can be prevented, and in addition, the spherical aberration of the main lens system can be reduced, so that the beam spot diameter can be reduced. The resolution can be improved by reducing the size.
[0029]
Next, an embodiment of the present invention for applying and forming conductive patterns such as the electrode films 111 to 113 and the conductive ring 114 on the inner surface of the high resistance tube 110 will be described.
[0030]
FIG. 1A is a longitudinal sectional view of the printing apparatus according to the first embodiment of the present invention, FIG. 1B is a transverse sectional view taken along line BB of FIG. Show. FIG. 2 shows an external perspective view of the printing apparatus.
[0031]
The printing device 1 includes a rod-shaped holding member 2 having a substantially cylindrical shape made of a hard material such as metal or plastic, for example, stainless steel, and natural rubber, NBR, fitted on the outer peripheral surface of the rod-shaped holding member 2 A transfer pad 3 made of rubber such as SBR, for example, silicone rubber, and a fastening band 4 made of metal, for example, for fastening both ends of the transfer pad 3 to the rod-like holding member 2 are provided. The basic configuration of this printing apparatus has already been proposed by the present applicant in Japanese Patent Application No. 8-146905 (filed on June 10, 1996).
[0032]
As shown in FIGS. 1A and 1B, the rod-shaped holding member 2 is provided with an air conduction path 21 along the central axis thereof, and communicates with the air conduction path 21 in the longitudinal direction of the rod-shaped holding member 2. Air blowing holes 22 are provided at four locations on the outer peripheral surface at approximately the center in the direction. The transfer pad 3 closes the air blowing hole 22 of the rod-shaped holding member 2 and is always in close contact with the outer peripheral surface 23 of the rod-shaped holding member 2 due to its rubber elasticity.
[0033]
As shown in FIG. 2, the rod-shaped holding member 2 has an end portion on the side where the air conduction path 21 is provided, and a rotary air joint 25 provided at the tip portion of the extension portion 24. Further, in the middle of the extension portion 24, a bearing portion 26 is provided for holding the printing device 1 rotatably by a drive device (not shown).
[0034]
As shown in FIG. 1A, the transfer pad 3 according to the present embodiment is configured such that the film thickness continuously decreases from the both end portions to the central portion. For example, when the inner diameter “a” of the high resistance tube 110 that is a printing medium is 12 mmφ and the outer diameter “b” of the transfer pad 3 is 11 mmφ, the inner diameter “c” at both ends of the transfer pad 3 is 7 mmφ (the film thickness t of the transfer pad 3 = 2 mm), and the inner diameter d at the central portion is 8.5 mmφ (the film thickness t of the transfer pad 3 is 1.25 mm). Incidentally, at this time, the inner diameter e of the air conduction path 21 is 1.5 mmφ, and the inner diameter f of the air blowing hole 22 is 0.5 mmφ.
[0035]
For example, as shown in FIG. 7, such a transfer pad 3 can be manufactured by molding using an inner mold 124 corresponding to the inner surface shape of the transfer pad 3 and an outer mold 125 corresponding to the outer surface shape. In addition, although the recessed part 31 for accommodating the fastening band 4 is provided in the outer surface both ends of the transfer pad 3, when the fastening band 4 is fastened, the fastening band 4 does not sunk into the outer surface of the transfer pad 3 and protrude. In such a case, it is not necessary to provide the recess 31.
[0036]
On the other hand, as shown in FIG. 1A, the outer peripheral surface 23 of the rod-shaped holding member 2 is formed in a shape in which the central portion bulges corresponding to the change in the film thickness of the transfer pad 3 described above. As a result, the change in the film thickness of the transfer pad 3 is canceled out, and the outer surface of the transfer pad 3 can be configured as one cylindrical surface as shown in the figure. In this way, by forming the outer surface of the transfer pad 3 into one cylindrical surface, as shown in the figure, the outer surface of the transfer pad 3 on which a transfer pattern to be described later is placed is a high resistance tube which is a printing body (work). The inner surface of 110 can be arranged close to each other at equal intervals. As a result, it is possible to perform accurate transfer with no printing deviation or the like on the work inner surface.
[0037]
Next, a method of printing a conductive pattern on the inner surface of the high resistance tube 110 (hereinafter referred to as “work W”) using the printing instrument 1 will be described.
[0038]
First, a conductive paste (for example, RuO), which is a printing ink, is applied to the surface of the transfer pad 3 (hereinafter also referred to as “effective print area”) that is not fastened by the fastening band 4 of the printing device 1. ₂ -Glass paste: Trade name # 9516, manufactured by DuPont) is attached in a predetermined pattern. A method for attaching the ink will be described later.
[0039]
Next, as shown in FIG. 2 and FIG. 1A, the central axis of the rod-shaped holding member 2 is set so that the transfer pad 3 does not hit the inner surface of the workpiece W in the workpiece W on which the inner surface is printed. The printing instrument 1 is inserted to a position to be printed while being aligned with the tube axis.
[0040]
Next, FIG. c ), From the air conduction path 21 of the rod-shaped holding member 2, for example, 3 to 5 kgf / cm ² Compressed air 5 is sent at a pressure of As a result, the inner surface of the transfer pad 3 that is in close contact with the outer peripheral surface 23 of the rod-shaped holding member 2 is pressurized from the portion of the air blowing hole 22, and the transfer pad 3 starts to expand. At this time, in the present embodiment, the transfer pad 3 is configured so that the film thickness of the transfer pad 3 is continuously reduced from both ends toward the center part. It swells sequentially toward both thick ends. Then, the outer surface of the transfer pad 3 is pressed against the inner surface of the work W sequentially from the center to both ends, and the ink adhering to the outer surface of the transfer pad 3 is transferred to the inner surface of the work W. Further, in the present embodiment, since the air blowing hole 22 is provided only in the central portion of the rod-shaped holding member 2, the transfer pad 3 is more likely to bulge from the central portion.
[0041]
In this way, the transfer pad 3 sequentially swells from the central portion toward both ends and comes into close contact with the inner surface of the work W, whereby the air between the outer surface of the transfer pad 3 and the inner surface of the work W is efficiently discharged, Air bubbles are reliably prevented from remaining between them. As a result, there is no print pattern defect due to poor adhesion between the outer surface of the transfer pad 3 and the inner surface of the workpiece W, and clean and reliable printing can be performed.
[0042]
In order to reliably obtain the above-described effect, the amount of change in the film thickness of the transfer pad 3 (= maximum film thickness t) _max / Minimum film thickness t _min ) Is preferably 133.3% (corresponding to the inner diameter d at the above-mentioned central portion corresponding to 8 mmφ) or more. If the amount of change is smaller than this, bubbles may remain between the outer surface of the transfer pad 3 and the inner surface of the workpiece W. On the other hand, considering the mechanical strength of the transfer pad 3, it is preferable that the upper limit of the change amount of the film thickness is 200% (the inner diameter d at the central portion described above corresponds to 9 mmφ). Of course, this upper limit can be increased as much as the mechanical strength of the material constituting the transfer pad allows.
[0043]
FIG. 1D shows a state where the entire outer surface of the transfer pad 3 is in close contact with the inner surface of the workpiece W. At this time, either the printing device 1 or the workpiece W may be rotated.
[0044]
Thereafter, the supply of the compressed air 5 to the rod-shaped holding member 2 is stopped, and the transfer pad 3 is contracted to return to be in close contact with the outer peripheral surface 23 of the rod-shaped holding member 2. Thereafter, the printing device 1 is extracted from the workpiece W. As a result, the ink pattern adhered to the outer surface of the transfer pad 3 is transferred to the inner surface of the work W, and the conductive paste pattern as shown in FIG. It is applied and formed on the inner surface. Thereafter, for example, the conductive paste applied to the inner surface of the high resistance tube 110 is baked at 850 ° C. for 10 minutes to complete printing.
[0045]
Next, a method for attaching ink to the transfer pad 3 will be described.
[0046]
As shown in FIG. 5, a concave plate 60 made of metal, glass, resin or the like and having a concave portion 61 of a pattern corresponding to a printing pattern formed by etching or the like is used. The ink 7 is placed on the concave portion 61 of the concave plate 60, and then scraped off by, for example, a doctor to fill the concave portion 61 with the ink 7 and flatten the surface of the ink 7. Next, the printing device 1 is rolled on the concave plate 60 in the direction of the arrow A, for example, and the ink 7 in the concave portion 61 is adhered to the outer surface of the transfer pad 3. As a result, the desired pattern of ink 7 adheres to the outer surface of the transfer pad 3.
[0047]
In the case of this example, the printing pattern 1 is symmetrical with respect to the axis of the workpiece W to which the ink 7 of each recess 61 adheres over the entire circumference of the outer surface of the transfer pad 3. Then, since the ink pattern attached to the outer surface of the transfer pad 3 is transferred to the inner surface of the workpiece W almost as it is, the printing pattern can be asymmetrical with respect to the axis of the workpiece W. It is possible to variously change the pattern shape of the concave portion 61 according to the above. That is, in the present invention, it is possible to accurately print even a considerably complicated pattern as compared with the transfer method in which the rubber roller as described above is rolled on the inner surface of the circular tube. Further, instead of the concave plate 60 as described above, for example, a waterless flat plate using the difference in the resilience of the silicon layer and the non-silicon layer ink is used, and the method is substantially the same as the method using the concave plate 60 described above. Thus, the ink can be attached to the outer surface of the transfer pad 3 in a predetermined pattern.
[0048]
FIG. 6 shows an example of a printing apparatus equipped with the printing device 1 of the present embodiment.
[0049]
As shown in the figure, the printing apparatus includes a V block 50 that holds the workpiece W, a mechanism (not shown) that moves the V block 50 in the direction of XX ′ in the drawing, a printing instrument 1, and a rotary drive for the printing instrument 1. A mechanism (not shown), a mechanism (not shown) for sending compressed air to the printing device 1, a concave plate 60, a mechanism (not shown) for moving the concave plate 60 in the YY 'direction in the figure, and the concave plate 60 A mechanism (not shown) for moving in the middle Z-Z ′ direction and a doctor 62 for scraping the surface of the concave plate 60 are provided.
[0050]
For example, at the start, the concave plate 60 is located below the position shown in the figure and is separated from the printing device 1. Therefore, first, the tube-shaped workpiece W on which the inner surface is printed is fixed to the V-shaped groove 51 of the V block 50. Thereby, the tube axis of the workpiece W and the central axis of the printing instrument 1 are arranged coaxially. Next, ink is filled into the concave portion 61 of the concave plate 60 by an ink supply device such as a roller (not shown), and the excess ink is scraped off by the doctor 62. Thereafter, the concave plate 60 is raised (Z ′ direction in the drawing) so that the upper surface of the concave plate 60 and the transfer pad 3 of the printing device 1 are in contact with each other. Next, the printing apparatus 1 is rotated in synchronization with the movement of the concave plate 60 while moving the concave plate 60 in the Y ′ direction in the drawing. As a result, the ink pattern on the concave plate 60 is transferred to the outer surface of the transfer pad 3 of the printing device 1, and the ink adheres to the outer surface in a predetermined pattern. Thereafter, the concave plate 60 is lowered (Z direction in the figure) and separated from the printing instrument 1. Next, the V block 50 is moved in the X ′ direction in the drawing, and the printing tool 1 is relatively inserted into the circular hole of the workpiece W. Thereafter, compressed air 5 is supplied to the printing instrument 1 from a compressor or the like (not shown), and the transfer pad 3 is expanded. As a result, the outer surface of the transfer pad 3 is pressure-bonded to the inner surface of the work W, and the ink adhering to the outer surface of the transfer pad 3 is transferred to the inner surface of the work W. Thereafter, the supply of the compressed air 5 is stopped, for example, by switching a valve (not shown). As a result, the transfer pad 3 contracts and returns to its original state, and the outer surface of the transfer pad 3 is separated from the inner surface of the workpiece W. Next, the V block 50 is moved in the X direction in the drawing, and the printing device 1 is relatively extracted from the workpiece W. Thereby, the transfer process is completed. In this printing apparatus, for example, transfer printing can be performed with high efficiency by automating the removal of the work W after the transfer and the attachment of a new work W.
[0051]
According to the first embodiment of the present invention described above, transfer printing can be performed on the inner surface of the printing medium (work) W very quickly by a simple operation and by a single transfer operation. In addition, since the printing apparatus 1 can be configured to be very thin, it can be suitably used, for example, when a conductive pattern is printed on the inner surface of a fairly small diameter high resistance tube 110 that constitutes the main lens system of the cathode ray tube. Further, since the transfer printing is used, there is no problem that the ink ejection holes are clogged as in the case of a direct drawing method such as a dispenser or an ink jet method.
[0052]
When it is desired to increase the printing film thickness, it is possible to print a thick film by repeating the above-described transfer operation once.
[0053]
In the first embodiment, the transfer pad 3 is configured such that the thickness of the transfer pad 3 gradually decreases from both ends toward the center, and when the transfer pad 3 expands, the outer surface of the transfer pad 3 It is made to contact | adhere to the inner surface of the to-be-printed body (work | work) W sequentially from a center part toward both ends. Therefore, the air between the outer surface of the transfer pad 3 and the inner surface of the printing medium (work) W can be efficiently discharged, and air bubbles can be reliably prevented from remaining between them. As a result, it is possible to perform clean and reliable printing with no defective printing such as missing patterns. Further, the pressure of the compressed air for expanding the transfer pad 3 can be set relatively low. As a result, the stress applied to the transfer pad 3 can be reduced, and the life of the transfer pad 3 can be extended. Can do. Furthermore, the outer peripheral surface 23 of the rod-shaped holding member 2 that holds the transfer pad 3 is configured to cancel the change in the film thickness of the transfer pad 3 so that the outer surface of the transfer pad 3 is in a contracted state. Constitutes one cylindrical surface, for example, the transfer accuracy of the printed material (work) W such as the high resistance tube 110 to the cylindrical inner surface can be extremely increased.
[0054]
Incidentally, comparing the case where the high resistance tube 110 for a cathode ray tube is manufactured using the printing apparatus 1 according to the first embodiment of the present invention and the case where it is manufactured by the conventional dispenser system, the throughput is as follows. The case was 1 minute / cycle, and the conventional case was 7 minutes / cycle. The product yield was 98% in the present invention and 80% in the conventional case. Therefore, it can be seen that the present invention enables highly efficient and accurate printing.
[0055]
In the first embodiment described above, when the length of the work W is shorter than the effective printing area of the transfer pad 3, auxiliary rings having an inner diameter substantially the same as the inner diameter of the work W are provided at both ends of the work W. May be arranged. Thereby, when the transfer pad 3 expands, it is possible to reliably prevent the transfer pad 3 from rupturing due to the expansion of the transfer pad 3 in the region between the short work W and the fastening band 4. However, in the first embodiment, since the film thicknesses at both ends of the transfer pad 3 are relatively large, the portions in the vicinity of both ends are relatively difficult to expand. Therefore, effective printing of the transfer pad 3 is possible. When the difference between the area and the length of the workpiece W is not so large, there is an effect that the transfer pad 3 is hardly ruptured without using the auxiliary ring as described above.
[0056]
Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, portions corresponding to those in the first embodiment described above are denoted by the same reference numerals as those in the first embodiment described above.
[0057]
As shown in FIG. 8, in the second embodiment, the thickness of the transfer pad 3 is configured to continuously change from one end to the other end. Further, the outer peripheral surface 23 of the rod-shaped holding member 2 is configured as a conical surface corresponding to the change in the film thickness of the transfer pad 3. As a result, the change in the film thickness of the transfer pad 3 is offset, and the outer surface of the transfer pad 3 is configured to form one cylindrical surface when the transfer pad 3 contracts. Further, air blowing holes 22 are provided on the outer peripheral surface 23 of the rod-shaped holding member 2 at four locations around the end of the transfer pad 3 where the film thickness is thin. The other configuration is the same as that of the first embodiment described above, and therefore detailed description thereof is omitted.
[0058]
Next, the operation of the printing device 1 according to the second embodiment will be described.
[0059]
First, as shown in FIG. 8A, the printing device 1 in which a predetermined pattern of ink is attached to the outer surface of the transfer pad 3 is placed in the circular hole of the workpiece W. Thereafter, as shown in FIG. 8B, the compressed air 5 is sent from the air conduction path 21 of the rod-shaped holding member 2 and blown out from the air blowing holes 22, thereby expanding the transfer pad 3. At this time, in the second embodiment, the transfer pad 3 is relatively thin at the end on the side where the air blowing holes 22 are provided. The expansion starts from the end of the thin film. Then, as shown in FIG. 8C, the transfer pad 3 sequentially expands from the end portion on the thin film thickness side toward the end portion on the thick film side, and closely contacts the inner surface of the workpiece W. Accordingly, the air between the outer surface of the transfer pad 3 and the inner surface of the workpiece W is pushed out by the expanding transfer pad 3 and is surely discharged, and bubbles are formed between the outer surface of the transfer pad 3 and the inner surface of the workpiece W. It is reliably prevented from remaining. As a result, as shown in FIG. 8D, the outer surface of the transfer pad 3 is securely adhered to the inner surface of the work W over the entire surface, and the reliable transfer onto the inner surface of the work W is performed.
[0060]
Therefore, also in the second embodiment, as in the first embodiment described above, there is an effect that it is possible to perform clean and reliable printing with no printing defects such as pattern defects. Further, the pressure of the compressed air for expanding the transfer pad 3 can be set relatively low. As a result, the stress applied to the transfer pad 3 can be reduced, and the life of the transfer pad 3 can be extended. The effect that it can do is also acquired. Furthermore, the outer peripheral surface 23 of the rod-shaped holding member 2 that holds the transfer pad 3 is configured to cancel the change in the film thickness of the transfer pad 3 so that the outer surface of the transfer pad 3 is in a contracted state. Is configured to form one cylindrical surface, for example, the effect that the transfer accuracy to the cylindrical inner surface of the printing object (work) W such as a high resistance tube for a cathode ray tube can be extremely increased is also obtained. .
[0061]
In the second embodiment, the amount of change in the film thickness of the transfer pad 3 (= maximum film thickness t) _max / Minimum film thickness t _min ) Is preferably 133.3% or more and 200% or less, as in the first embodiment described above. If the amount of change in the thickness of the transfer pad 3 is less than 133.3%, bubbles may remain between the outer surface of the transfer pad 3 and the inner surface of the workpiece W. Further, if the amount of change in film thickness exceeds 200%, the mechanical strength of the transfer pad 3 is weakened, and the transfer pad 3 may be easily damaged.
[0062]
Further, in the second embodiment, the position where the air blowing hole 22 is provided is in the vicinity of the end portion on the side where the film thickness of the transfer pad 3 is thin as in the illustrated example. However, for example, when the expansion of the transfer pad 3 is performed at a relatively low pressure, the influence of the change in the film thickness appears so strongly that the air blowing hole 22 is transferred. It can also be provided in the vicinity of the center portion of the pad 3 or in the vicinity of the end portion on the opposite side on the thick side. Further, the air blowing holes 22 may be provided around a plurality of locations in the longitudinal direction (axial direction) of the rod-shaped holding member 2.
[0063]
FIG. 9 shows a third embodiment of the present invention. In the third embodiment, parts corresponding to those in the first embodiment described above are denoted by the same reference numerals as those in the first embodiment described above.
[0064]
In the third embodiment, in the same configuration as in the first embodiment described above, the air blowing holes 22 are provided at a plurality of locations (5 locations in the illustrated example) in the longitudinal direction (axial direction) of the rod-shaped holding member 2. ) Is provided around. Other configurations are the same as those in the first embodiment described above.
[0065]
Even in the configuration of the third embodiment, the transfer pad 3 sequentially expands from the thin central portion toward both thick end portions, and sequentially works from the central portion toward both end portions. Adheres to the inner surface of W. Therefore, as in the case of the first embodiment described above, the air between the outer surface of the transfer pad 3 and the inner surface of the workpiece W is pushed out to the expanding transfer pad 3 and reliably discharged, and the transfer pad 3 is discharged. Air bubbles are reliably prevented from remaining between the outer surface of the workpiece and the inner surface of the workpiece W. As a result, as in the first embodiment described above, it is possible to obtain an effect that it is possible to perform clean and reliable printing without print defects such as pattern chipping.
[0066]
Further, in the third embodiment, the expansion method of the transfer pad 3 is finely adjusted by sequentially decreasing or increasing the diameter of the air blowing hole 22 from the central portion of the transfer pad 3 toward both ends. Is possible.
[0067]
In FIG. 10, the structure of the rod-shaped holding member 2 by the 4th Embodiment of this invention is shown. The configuration other than the rod-shaped holding member 2 is the same as that of the first embodiment described above.
[0068]
In the fourth embodiment, a groove 27 continuous with the air blowing hole 22 is provided on the outer peripheral surface 23 of the rod-shaped holding member 2. As a result, as in the third embodiment shown in FIG. 9, the compressed air blown from the air blowing holes 22 is supplied almost evenly to the inner surface of the transfer pad 3. Therefore, substantially the same effect as that of the third embodiment described above can be obtained. Moreover, in the fourth embodiment, the processing of the rod-shaped holding member 2 is simpler than the third embodiment described above. Furthermore, in the fourth embodiment, compressed air blows more strongly at the center portion of the transfer pad 3 than in the case of the third embodiment described above, so that the transfer pad 3 sequentially expands from the center portion. Easy to control. Also in the fourth embodiment, the shape of the groove 27 is transferred by, for example, narrowing or widening the width sequentially from the center to both ends, or shallowing or deepening the depth. It is possible to finely adjust how the pad 3 expands.
[0069]
FIG. 11 shows a fifth embodiment of the present invention. In the fifth embodiment, parts corresponding to those of the first embodiment described above are denoted by the same reference numerals as those of the first embodiment described above.
[0070]
In the fifth embodiment, the thickness of the transfer pad 3 is changed intermittently rather than continuously. That is, as shown in the drawing, the thickness of the transfer pad 3 is not changed continuously between the central portion and both end portions, but is relatively abrupt at a predetermined portion between the central portion and both end portions. To change. The outer peripheral surface 23 of the rod-shaped holding member 2 is configured to have a shape that cancels out the change corresponding to the change in the film thickness of the transfer pad 3. Other configurations are the same as those in the first embodiment described above.
[0071]
Even when configured as in the fifth embodiment, the transfer pad 3 sequentially expands from the thin central portion toward both thick end portions, and from the central portion to both end portions. In close contact with the inner surface of the workpiece W. Therefore, as in the case of the first embodiment described above, the air between the outer surface of the transfer pad 3 and the inner surface of the workpiece W is pushed out to the expanding transfer pad 3 and reliably discharged, and the transfer pad 3 is discharged. Air bubbles are reliably prevented from remaining between the outer surface of the workpiece and the inner surface of the workpiece W. As a result, as in the first embodiment described above, it is possible to obtain an effect that it is possible to perform clean and reliable printing without printing defects such as pattern chipping.
[0072]
In the fifth embodiment, it is possible to adjust the expansion method of the transfer pad 3 by changing the position where the film thickness of the transfer pad 3 is changed. It is also possible to use a combination of a location where the thickness of the transfer pad 3 is changed intermittently and a location where the thickness is changed continuously.
[0073]
FIG. 12 shows the configuration of the transfer pad 3 according to the sixth embodiment of the present invention. In the sixth embodiment, in the same configuration as the fifth embodiment described above, the change position of the film thickness of the transfer pad 3 is provided at a plurality of locations, and the film thickness of the transfer pad 3 is changed stepwise. ing. Although not shown, the outer peripheral surface 23 of the rod-like holding member 2 that holds the transfer pad 3 is configured to cancel the change corresponding to the change in the film thickness of the transfer pad 3. Other configurations are the same as those in the first embodiment described above.
[0074]
In the sixth embodiment, compared with the fifth embodiment described above, the manner of expansion of the transfer pad 3 that is closer to that in the first embodiment can be obtained. Therefore, substantially the same effect as that of the first embodiment described above can be obtained. Moreover, in the sixth embodiment, the manner in which the transfer pad 3 expands can be finely adjusted by variously changing the position where the film thickness of the transfer pad 3 is changed. It is also possible to use a combination of a location where the thickness of the transfer pad 3 is changed intermittently and a location where the thickness is changed continuously.
[0075]
In the sixth embodiment, the film thickness of the transfer pad 3 is gradually reduced from one end to the other end of the transfer pad 3 so as to correspond to the second embodiment described above. You may make it become. In that case, substantially the same effect as that of the second embodiment described above can be obtained.
[0076]
While the present invention has been described according to the preferred embodiment, the present invention is not limited to the above-described embodiment. For example, in the above-described embodiment, compressed air is used to expand the transfer pad 3. However, as the pressurized fluid for expanding the transfer pad 3, a gas other than air or a liquid such as oil is used. You can also.
[0077]
Further, the printing body (work) for printing on the inner surface is not limited to the high resistance tube constituting the electron lens system of the cathode ray tube exemplified in the above-described embodiment. For example, a rotary transformer coil such as a VTR or a motor The present invention can be applied to inner surface printing of various cylindrical parts such as stator coils and rotor coils.
[0078]
The present invention is not limited to printing a conductive pattern, but can also be applied to printing an insulating pattern. Furthermore, in the present invention, a conductive pattern and an insulating pattern can be printed simultaneously.
[0079]
Further, the present invention is not limited to a cylindrical part, and can be applied to printing a circular hole or an inner surface of a hole of a printing medium. Furthermore, if the shape of the hole or hole of the printing medium is not a perfect circle, it can be printed easily and accurately by using the printing device of the present invention having a cross-sectional shape corresponding to the circle. Furthermore, the present invention is not limited to a hole or an inner surface of a hole, but can be applied to printing on a curved surface to be printed such as an inner surface of a groove.
[0080]
【The invention's effect】
In the present invention, the transfer pad provided on the outer peripheral surface of the holding member is expanded toward the printing surface, the expanded transfer pad is brought into contact with the printing surface, and the ink previously attached to the outer surface of the transfer pad is removed. When transferring to the printing surface, At the position of the pressurized fluid outlet Transfer pad thickness Relatively small The transfer pad Number The printing surface is continuously contacted sequentially from the place. Therefore, the air between the outer surface of the transfer pad and the printing surface can be efficiently discharged, and air bubbles are reliably prevented from remaining between them. As a result, it is possible to perform clean and reliable printing with no defective printing such as missing patterns. Further, the pressure for expanding the transfer pad can be set relatively low. As a result, the stress applied to the transfer pad can be reduced, and the life of the transfer pad can be extended.
[0081]
In addition, the outer peripheral surface of the holding member that holds the transfer pad is configured to cancel the change corresponding to the change in the thickness of the transfer pad, and when the transfer pad is contracted, the outer surface of the transfer pad is For example, configured to form one cylindrical surface if For example, the transfer accuracy to the cylindrical inner surface of the printing medium can be made extremely high.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a printing apparatus according to a first embodiment of the present invention.
FIG. 2 is an external perspective view of the printing apparatus according to the first embodiment of the present invention.
FIG. 3 is a schematic cross-sectional view showing a high resistance tube for a cathode ray tube as a work printed by the printing instrument of the present invention.
4 is an enlarged cross-sectional view of the high resistance tube shown in FIG.
FIG. 5 is a schematic view showing a method of supplying ink to the printing apparatus according to the first embodiment of the present invention.
FIG. 6 is a schematic diagram illustrating a printing method by a printing apparatus including the printing apparatus according to the first embodiment of the present invention.
FIG. 7 is a schematic cross-sectional view showing the method for manufacturing the transfer pad of the printing device according to the first embodiment of the present invention.
FIG. 8 is a cross-sectional view of a printing apparatus according to a second embodiment of the present invention.
FIG. 9 is a cross-sectional view of a printing apparatus according to a third embodiment of the present invention.
FIG. 10 is a partially broken perspective view of a rod-shaped holding member of a printing apparatus according to a fourth embodiment of the present invention.
FIG. 11 is a sectional view of a printing apparatus according to a fifth embodiment of the present invention.
FIG. 12 is a sectional view of a transfer pad of a printing apparatus according to a sixth embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Printing instrument, 2 ... Bar-shaped holding member, 3 ... Transfer pad, 4 ... Fastening band,
5 ... Compressed air, 7 ... Ink, 21 ... Air conduction path, 22 ... Air blowing hole,
23 ... Outer peripheral surface, 24 ... Extension part, 25 ... Rotary air joint,
26 ... bearing part, 50 ... V block, 51 ... V-shaped groove, 60 ... concave plate,
61 ... concave portion, 62 ... doctor, 100 ... cathode ray tube, 110 ... high resistance tube,
111-113 ... Electrode film, 114 ... Conductive ring, W ... Workpiece

Claims (16)

A holding member having a blowout hole for pressurized fluid on the outer peripheral surface;
Said spaced can cover the outer peripheral surface of the holding members, said expanded by pressure of pressurized fluid, and a transfer pad to return to the original state by contracting when releasing the pressure, the blowing holes A printing instrument characterized in that the film thickness of the transfer pad is relatively small at the position .   The printing apparatus according to claim 1, wherein the holding member has a rod shape, and a film thickness of the transfer pad changes in a longitudinal direction of the holding member.   The printing instrument according to claim 1, wherein the thickness of the central portion of the transfer pad is smaller than the thickness of both end portions.   The printing apparatus according to claim 1, wherein the film thickness decreases from one end of the transfer pad to the other end.   The printing apparatus according to claim 1, wherein the thickness of the transfer pad is continuously changed.   The printing apparatus according to claim 1, wherein the thickness of the transfer pad changes stepwise. The printing apparatus according to claim 1 , wherein the blowout hole is provided around one place in a longitudinal direction of the holding member. The printing apparatus according to claim 1 , wherein the blowout holes are provided around a plurality of locations in the longitudinal direction of the holding member.   The printing apparatus according to claim 1, wherein the outer peripheral surface of the holding member is configured in a shape corresponding to a change in the film thickness of the transfer pad. The printing apparatus according to claim 9 , wherein an outer peripheral surface of the transfer pad is substantially in the same cylindrical surface. A printing device comprising: a holding member having a blowout hole for pressurized fluid on an outer peripheral surface; and a transfer pad that covers the outer peripheral surface of the holding member so as to be separable and has a relatively small film thickness at the position of the blowout hole Facing the printing surface, the transfer pad is expanded by pressurization of the pressurized fluid and brought into contact with the printing surface, and the ink previously attached to the outer peripheral surface of the transfer pad is transferred to the printing surface. How to print. The printing method according to claim 11 , wherein the printing surface is a curved surface. The printing method according to claim 12 , wherein the holding member is rod-shaped, and the printing surface is an inner surface of a hole provided in the printing medium. The printing method according to claim 13 , wherein the transfer pad sequentially contacts the inner surface of the hole sequentially from the center to both ends. The printing method according to claim 13 , wherein the transfer pad sequentially contacts the inner surface of the hole sequentially from one end portion to the other end portion thereof. The printing method according to claim 11 , which is applied when a conductive pattern is formed on an inner peripheral surface of a cylindrical part or a cylindrical portion.

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