JP5441515B2 - Work transfer method and jig for surface treatment tank - Google Patents

Description

  The present invention relates to a work transfer method for transferring a workpiece such as a printed circuit board in a substantially horizontal state in a surface treatment tank such as a cleaning tank or a plating tank, and a transfer jig used for the transfer.

  In the manufacturing process of workpieces such as printed circuit boards used in electronic equipment, surface treatment tanks such as various washing tanks or plating tanks are used. Surface treatment is performed by the above.

  As a method of transporting the workpiece in the surface treatment tank, both ends in the width direction of the workpiece are sandwiched by a pair of transport rollers composed of upper and lower transport rollers, and the workpiece is transported in a horizontal state by rotation of the transport roller. The method is adopted. That is, the work is horizontally transported in the surface treatment tank, and during transport, cleaning liquid, chemical liquid or water is sprayed from the upper and lower nozzles, or the stored plating liquid is passed (Patent Documents 1 and 2, etc.) reference).

JP 2008-285323 A JP 2008-85119 A

  Since the recent printed circuit boards used in electronic devices are becoming extremely thin and flexible, the both ends in the width direction of the workpiece are simply sandwiched by the transport rollers and horizontally transported in the transport direction. Due to the momentum of the processing liquid being sprayed and the weight of the processing liquid, the workpiece is slackened, the processing liquid does not spread evenly over the entire surface of the workpiece, the quality of the surface treatment is reduced, and the pair of left and right transport rollers are clamped Due to variations in pressure or frictional force, the workpiece meanders, which may also reduce the quality.

  On the other hand, in the technologies disclosed in each of the above prior art documents, the shaft core of the transport roller is inclined with respect to the width direction perpendicular to the transport direction, so that the outer side in the width direction with respect to the workpiece being transported. A tensile force is applied to the workpiece, thereby preventing the workpiece from loosening.

  However, in any of the prior art techniques, it has been impossible to reliably prevent the workpiece from loosening and the workpiece from meandering. Further, in order to increase the contact surface between the conveying roller pair and the workpiece, it is conceivable to increase the arrangement density of the conveying roller pair, but the number of parts increases and the cost increases.

  The present invention has been made in view of the above problems, and enables a workpiece to be horizontally transported along a transport direction in a planar state without causing slack and meandering. It is an object. Another object of the present invention is to enable even a very thin and flexible workpiece to be transported horizontally without increasing the number of transport roller pairs.

In order to solve the above-described problems, the present invention provides a plurality of transport roller devices each having a transport roller pair composed of transport rollers opposed to each other at a predetermined interval in the work transport direction in the width direction of the work transport path. provided on both sides, the roller axis of each transport roller pair, as viewed from above, the inner side of the width direction is inclined to come to the conveying direction, Ri by the above two conveying rollers device, the rectangular shaped workpieces both end portions gripping the upper and lower width direction of the workpiece transfer method for the surface treatment tank for transporting a workpiece in horizontal state, among the both sides in the width direction of the workpiece conveying path, at least one, work transfer path and Rights A conveyance guide extending in a row is laid, and of the pair of conveyance roller devices, the roller clamping pressure of the conveyance roller device on the side where the conveyance guide is disposed is higher than the roller clamping pressure of the other conveyance roller device. Ku is set, by the difference in the roller nip Ji圧, with drawing the workpiece to the transport guide side, pressed against the conveying guide to guide the conveying direction,
The both ends of the workpiece in the width direction are sandwiched from above and below by the conveying jig over the entire length of the workpiece in the conveying direction, and each conveying jig is vertically moved by the conveying roller pair of the corresponding conveying roller device. The workpiece is conveyed while being pulled outward in the width direction through the both conveying jigs on both sides in the width direction by the rotation of each pair of conveying rollers.

Moreover, this invention provides the jig | tool for conveyance used for the said conveying method. The transport jig, both ends of the width direction of the work of rectangular shape arranged horizontal posture from above and below a conveying jig for clamping, and a upper jig member and the lower jig member The two jig members have a high friction coefficient holding surface that abuts on the upper and lower surfaces of the end portion in the width direction of the workpiece, respectively, and one jig member is disposed at an interval in the workpiece conveyance direction. A projection is formed, and the other jig member is formed with a fitting hole into which the projection is fitted. Each projection contacts the edge in the width direction of the workpiece and conveys the edge. positioning in the direction of the flat row.

  In the conveying jig, preferably, the protrusion is formed in a columnar shape, and the fitting hole is formed in a circular shape.

Further, as a separate conveying jig, the both ends in the width direction of the work of rectangular shape arranged horizontal posture from above and below a conveying jig for clamping, the upper jig member and the lower jig And both jig members have clamping surfaces with a high coefficient of friction that are in contact with the upper and lower surfaces of the end portion in the width direction of the workpiece, respectively, and one jig member has a workpiece conveyance of the jig member. A stair-like step portion extending over the entire length in the direction is formed, and the other jig member is formed with a fitting groove into which the step portion is fitted, and the step portion is an edge in the width direction of the workpiece. providing transport jig, characterized in that contact with positioning the edge in the conveying direction and flat row to.

(1) According to the conveying method according to the present invention, the workpiece in the width direction is clamped from above and below by the inclined conveying rollers, and a difference is given to the roller clamping pressure of both conveying roller devices. Is pulled to the outside of the width direction while being pulled toward the conveying roller device side where the roller clamping pressure is high, and is pressed against the conveying guide to convey the workpiece, so that the workpiece is flattened without causing slack and meandering. In this state, it can be reliably transported along the transport direction and can be transported smoothly. As a result, the entire surface of the workpiece can be uniformly treated and the quality of the surface treatment of the workpiece can be improved.

(2) The both ends of the workpiece in the width direction are sandwiched from above and below by a conveying jig that extends over the entire length of the workpiece in the conveying direction and conveyed, so even if the workpiece is extremely thin, Even if a large number is not installed, loosening of the workpiece can be reliably prevented and the workpiece can be transported in a flat state.

(3) The conveying jig preferably includes an upper jig member and a lower jig member that are positioned with respect to each other by the protrusion and the fitting hole, and the edge of the workpiece is positioned by using the protrusion. If it is set as the structure which performs, it can position a workpiece | work reliably to a predetermined fixed position with a simple structure.

(4) Moreover, since the conveyance jig can be detachably attached to the workpiece, it can be used repeatedly, contributing to cost reduction.

It is a schematic sectional drawing of the surface treatment tank (cleaning tank) with which the conveyance method concerning this invention is implemented. It is the II-II cross-sectional enlarged view of FIG. It is the III-III cross-sectional enlarged view of FIG. It is an expanded sectional view of the arrow IV part of FIG. It is VV sectional drawing of FIG. It is a disassembled perspective view of the bearing of a conveyance roller apparatus. It is a disassembled perspective view of the conveyance jig. It is a front view of the jig for conveyance of FIG. It is a top view which shows the modification of a conveyance roller apparatus. It is a perspective view which shows each process in the workpiece conveyance method which concerns on this invention. It is a disassembled perspective view which shows the modification of the jig | tool for conveyance. It is a front view of the jig for conveyance of FIG. It is a top view which shows the modification of a conveyance roller apparatus. The cross-sectional enlarged view similar to FIG. 2 of the surface treatment tank in which another conveyance method according to the present invention is implemented, A schematic plan view of a conveying roller device used in an experimental example of the present invention, FIG. 15 is a graph showing experimental results based on the apparatus of FIG. Cross-sectional enlarged schematic view of a transport roller device used in another experimental example of the present invention, It is a graph showing the experimental result based on the apparatus of FIG.

  1 to 8 show a surface treatment tank and a workpiece conveyance jig for carrying out a workpiece conveyance method according to the present invention. First, an example of a surface treatment apparatus will be described based on these drawings.

  FIG. 1 is a schematic vertical cross-sectional view of the entire surface treatment tank. As the surface treatment tank, a washing tank 1 for continuously washing a thin workpiece such as a printed circuit board is provided. The arrow F is the workpiece conveyance direction. For convenience of explanation, the horizontal direction orthogonal to the workpiece conveyance direction is referred to as “width direction” or “left-right direction” and will be described below.

  A work inlet 2 and a work outlet 3 are provided at a rear end and a front end of the work transfer direction F of the cleaning tank 1, and a loading tank 4 and an unloading tank 5 are connected to each other. In the tank 5, conveyance rollers 6 and 7 are arranged for carrying in and out the workpiece W in a horizontal state.

  In the cleaning tank 1, a work transfer device 11 having a plurality of transfer roller pairs 10, a plurality of upper cleaning liquid nozzles 12, and a plurality of lower cleaning liquid nozzles 13 are arranged. The pair of transport rollers 10 is arranged with a predetermined interval in the transport direction F, and is composed of an upper transport roller 15 and a lower transport roller 16 that face each other in the vertical direction, and between the transport rollers 15 and 16. The workpiece conveyance path A through which the workpiece W passes in a horizontal posture is configured. The conveyance speed of the workpiece conveyance device 11 is, for example, 0.5 m to 2 m per minute. In FIG. 1, for convenience of description space, only a part of the plurality of transport roller pairs 10 and the plurality of cleaning liquid nozzles 12 and 13 are denoted by reference numerals, and the rest are omitted.

  Although not shown, each of the cleaning liquid nozzles 12 and 13 communicates with the cleaning liquid supply unit via a plurality of pipes, and sprays the cleaning liquid from the upper side and the lower side with respect to the work W transported horizontally in the transport path A. Both sides are designed to be cleaned. At the lower end portion of the cleaning tank 1, the sprayed cleaning liquid is accumulated up to the level L1.

  2 is an enlarged sectional view taken along the line II-II in FIG. 1, and FIG. 3 is a sectional view taken along the line III-III in FIG. 2. In FIG. For the transport rollers 15 and the like, only a part is given a reference numeral, and the rest is omitted. In FIG. 2, the transport roller device 11 is disposed on both sides in the width direction (left and right direction) orthogonal to the transport direction F, and each transport device 11 has the left and right ends of the workpiece W placed on the transport jig 18. The upper and lower conveying rollers 15 and 16 are sandwiched from above and below to be conveyed. The material of the transport rollers 15 and 16 is, for example, rubber, and can be elastomer or natural rubber. Since it is preferable to have chemical resistance, metal or Teflon resin (registered trademark) is also possible.

  The support structure and drive structure of the transport roller device 11 will be described. In the cleaning tank 1, a pair of inner support walls 41 are erected at intervals in the left-right direction, and the outer support walls are located at positions spaced from the inner support walls 41 outward in the left-right direction. 42 is erected. The roller shafts 21 and 22 of the transport rollers 15 and 16 are rotatably supported by the inner and outer support walls 41 and 42 via inner and outer bearings 43 and 44, respectively. The inner support wall 41 is provided with a gap adjusting mechanism (roller pressure adjusting mechanism) 45 for adjusting a gap (roller clamping pressure) between the upper and lower conveying rollers 15 and 16.

  Each upper transport roller shaft 21 and each corresponding lower transport roller shaft 22 are interlocked and connected via flat gears 23 and 24, respectively.

  Below each lower conveyance roller shaft 22, a power transmission shaft 34 is rotatably mounted across the left and right support walls 41, 42, and a plurality of power transmission shafts 34 are provided in the vicinity of both left and right ends of the power transmission shaft 34. The flat gear 24 of each lower conveyance roller shaft 22 is meshed with the flat gear 25.

  In FIG. 3, a drive shaft 31 extending in parallel with the transport direction F is disposed at one end portion in the left-right direction in the cleaning tank 1, for example, the left end portion in FIG. 3, and one end of the drive shaft 31 in the length direction. The unit is connected to a drive source such as a drive motor via a power transmission mechanism (not shown). In the middle of the drive shaft 31, bevel gears 32 are fixed at positions corresponding to the respective transport roller pairs 10 at equal intervals in the transport direction F, and each bevel gear 32 is connected to the left end of each power transmission shaft 34. It meshes with a bevel gear 33 fixed to the part.

  That is, the rotation of the drive shaft 31 rotated by a drive motor or the like is transmitted to the power transmission shaft 34 via the bevel gears 32 and 33, and the flat gear 24 shown in FIG. 25, and is transmitted to the lower transport roller shaft 22 and the upper transport roller shaft 21, respectively, to rotate the transport rollers 15 and 16 in opposite directions.

  In FIG. 3, the axis of the left and right upper transport roller shafts 21 has a predetermined angle θ1 with respect to the width direction (left and right direction) perpendicular to the transport direction F, so It is inclined. The axis of each lower conveyance roller shaft 22 shown in FIG. 2 is also inclined with respect to the width direction (left-right direction) at the same angle θ1 as that of the upper conveyance roller shaft 21.

  In order to support the transport roller shafts 21 and 22 in the inclined state as described above, the center line of the bearing hole formed in each of the bearings 43 and 44 is also at the predetermined angle θ1 with respect to the width direction (left and right direction). The inner bearings 43 are arranged at positions that are inclined and are shifted to the conveying direction F side with respect to the outer bearings 44.

  In addition, a stopper 46 that can contact the inner surface of the outer bearing 44 in the left-right direction is fixed in the middle of each of the transport roller shafts 21, 22, so that the transport roller shafts 21, 22 are in the roller axis direction. Prevents movement.

  FIG. 4 is an enlarged cross-sectional view taken along arrow IV in FIG. 1 and shows the structure of the gap adjusting mechanism 45. The inner bearing 43 is formed with a circular bearing hole 47 for the lower conveying roller shaft 22 and a vertically long bearing hole 48 for the upper conveying roller shaft 21, and the lower conveying roller shaft 22 has a diameter. The upper conveying roller shaft 21 is supported by the upper bearing hole 48 so as to be movable in the vertical direction.

  The gap adjusting mechanism 45 includes a case 51 fixed to the upper surface of the inner support wall 41 by a mounting bolt 55 and a pressing rod 52 that penetrates the lower wall of the case 51 and enters the upper bearing hole 48 so as to be movable in the vertical direction. And a coil spring 53 connected to the upper end surface of the holding rod 52, and an adjustment screw 54 connected to the upper end of the coil spring 53 and screwed into the female screw hole of the upper wall of the case 51. Yes.

  The lower end of the presser rod 52 is formed in an arcuate concave surface and can come into contact with the upper surface of the upper transport roller shaft 21. By changing the tightening amount of the adjusting screw 54, the position of the presser rod 52 in the vertical direction is adjusted, so that the gap (roller clamping pressure) between the upper and lower conveying rollers 15 and 16 can be adjusted. Yes.

  FIG. 5 is a VV end view of FIG. 4, and the left and right transport roller devices 11 are each provided with a roller gap adjusting mechanism 45, but the roller clamping pressure is set to a different value. In this embodiment, the clearance between the upper and lower transport rollers 15 and 16 of the left transport roller device 11 is adjusted to be smaller than the clearance between the upper and lower transport rollers 15 and 16 of the right transport roller device 11. Has been. That is, the left and right clearances are set so that the roller clamping pressure of the left conveyance roller device 11 is larger than the roller clamping pressure of the right conveyance roller device 11.

  As described above, when the roller holding pressure of the left conveyance roller device 11 is set high, a guide having a smooth surface with a small friction coefficient is provided on the right end surface of the left inner bearing 43 as a conveyance guide. Tape 60 is affixed. That is, the guide tape 60 is attached to the end surface of the inner bearing 43 on the side where the roller clamping pressure is set high. The guide tape 60 is disposed at a height including the conveyance path A.

  FIG. 6 is an exploded perspective view of the inner bearing 43. The inner support wall 41 is formed with bearing mounting holes 70 that are long in the vertical direction and open at the upper end. Is formed with a groove 71 that can be fitted to the inner peripheral surface of the bearing mounting hole 70. The inner bearing 43 is fitted into the bearing mounting hole 70 from above, and the upper end surface of the inner bearing 43 is pressed by the lower end surface of the case 51 of the gap adjusting mechanism 45 as shown in FIG.

  The structure of the transfer jig 18 for holding the workpiece W will be described with reference to FIGS. FIG. 7 is an exploded perspective view of the conveying jig 18. The conveying jig 18 includes an upper jig member 72 and a lower jig member 73 that are elongated in the workpiece conveying direction F. The lengths of the members 72 and 73 are set to be approximately equal to the length of the workpiece W in the conveyance direction. The materials of the jig members 72 and 73 are, for example, polyvinyl chloride (PVC), polypropylene (PP), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), polyvinylidene fluoride (PVDF), or polyether ether. A resin such as ketone (PEEK), which has chemical resistance and durability, is preferable.

  A plurality of cylindrical protrusions 74 are formed on the upper surface of the lower jig member 73 at equal intervals in the length direction of the lower jig member 73 (work transfer direction). Each cylindrical protrusion 74 is formed in the same shape and the same size, and the lower jig member is arranged so that the centers thereof are aligned on a straight line parallel to the length direction of the lower jig member 73. 73 is arranged at the center in the width direction. Thereby, the right end edge and the left end edge of all the cylindrical protrusions 74 are respectively positioned on a straight line parallel to the length direction of the lower jig member 73. Between the left and right edges of each cylindrical protrusion 74 and the left and right edges of the lower jig member 73, a non-slip tape (friction tape) 75 having a large friction coefficient is attached. The width of the anti-slip tape 75 is the width of the workpiece W. If the width of the workpiece W is about 400 mm, the width of the anti-slip tape 75 (the clamping width) is sufficient to maintain a sufficient clamping state. ) Needs, for example, about 5 mm to 10 mm. The material of the anti-slip tape 75 is, for example, a resin such as soft polyvinyl chloride (PVC) silicon rubber or rubber, and is preferably excellent in chemical resistance and durability.

  The upper jig member 72 has a plurality of fitting holes 76 into which the cylindrical protrusions 74 of the lower jig member 73 are fitted at equal intervals in the length direction of the upper jig member 72 (work transfer direction). Is formed. Further, a non-slip tape 77 similar to the anti-slip tape 75 of the lower jig member 73 is attached to the left and right ends of the lower surface of the upper jig member 72.

  Although not shown, R surfaces are formed at the four corners of the upper and lower jig members 72 and 73.

  FIG. 9 shows a modified example of the transport roller device 11, which slightly simplifies the drive system, narrows the roller interval in the work transport direction F, and reduces the number of power transmission shafts. That is, as compared with the structure of FIG. 3, the power transmission shafts 34 connecting the left and right transport roller devices 11 are thinned out every other and the lower transport roller shaft 22 adjacent to the work transport direction F (see FIG. 3). 9 is hidden by the lower side of the upper roller shaft 21) by a pair of gears 68, 68 and an intermediate gear 69. The other structure is the same as the structure shown in FIGS.

[Overall flow of surface treatment work]
In FIG. 1, a rectangular workpiece W such as a printed circuit board is supplied in a horizontal state onto a conveying roller 6 of a loading tank 4 by an automatic loading mechanism or manually, and passes through an inlet 2 by the conveying roller 6. It is conveyed into the cleaning tank 1.

  In the cleaning tank 1, the workpiece W is transported in the transport direction F by the left and right transport roller devices 11, cleaned by the cleaning liquid sprayed from the upper and lower cleaning liquid nozzles 12, 13, passes through the outlet 3, and is unloaded from the unloading tank 5. To be discharged. In the unloading tank 5, the workpiece W is taken out by an automatic unloading mechanism or manually, and supplied to the next step, for example.

[One specific example of workpiece transfer method and its effect]
A specific work transfer method in the surface treatment operation as described above will be described with reference to FIG. FIG. 10 shows a transport process when the transport device 11 described in the modification is provided.

(1) As a pre-process of the loading operation, as shown in the upper right end of FIG. 10, the left and right ends of the rectangular workpiece W are sandwiched from above and below by the conveying jig 18. This clamping operation can be performed automatically by an automatic attachment mechanism attached to the automatic loading mechanism or manually. In this clamping operation, the left and right edges of the workpiece W are brought into contact with the cylindrical protrusions 74 of the lower jig member 73, as shown in FIG. Perform positioning. Then, the cylindrical protrusion 74 is fitted into the fitting hole 76 and the upper jig member 72 is overlapped with the lower jig member 73, whereby the left and right ends of the workpiece W are sandwiched between the upper and lower antiskid tapes 77 and 75. Hold the part.

(2) Returning to FIG. 10, the workpiece W sandwiched between the left and right ends by the conveying jig 18 is carried into the cleaning tank 1 from the loading tank 4, and the left and right conveying jigs 18 are moved to the upper and lower conveying rollers 15. , 16 and conveyed in the conveying direction F by the rotation of the conveying rollers 15 and 16. In this transport process, as shown in FIG. 3, the shaft cores of the left and right transport roller pairs 10 are inclined at a predetermined angle θ1 so that the inner side in the left-right direction is on the transport direction F side. It is conveyed in a state where it receives tension in the left and right direction via the left and right conveying jigs 18.

  Thereby, the workpiece W is conveyed while maintaining a horizontal plane state, and even if the cleaning liquid collides with force from above and below, the workpiece does not loosen, become wrinkled or come off. Further, by maintaining the horizontal flat state, the cleaning liquid can be distributed almost uniformly over the entire surface of the work, and high-quality cleaning performance can be obtained.

  In particular, the left and right ends of the work W are sandwiched by the transport jig 18 over substantially the entire length in the transport direction F of the work, and the transport jig 18 is sandwiched and transported by the upper and lower transport rollers 15 and 16. Therefore, even if there is a slight variation in the roller clamping pressure of each conveyance roller pair 10 in each conveyance roller device 11, the entire length of the workpiece W in the conveyance direction can be uniformly clamped. It is possible to prevent the occurrence of wrinkles, dropping off and meandering.

(3) In FIG. 5, in this embodiment, the roller clamping pressure of the left conveying roller device 11 is made larger than the roller clamping pressure of the right conveying roller device 11, and the right end surface of the left inner bearing 43 In addition, since the guide tape 60 having a small friction coefficient is attached, the workpiece W is attracted to the left side where the roller clamping pressure is strong during the workpiece conveyance, and the conveyance jig 18 on the left side of the workpiece W contacts the guide tape 60. The contact state is maintained. In other words, the workpiece W is accurately guided in the transport direction F by the guide tape 60, and is accurately transported in the transport path A without being skewed.

  In this embodiment, the guide tape 60 is attached to each inner bearing member 43. However, since the R surfaces are formed at the four corners of the conveying jig 18, the conveying jig 18 has one inner side. Even when abutting against the edge of the next inner bearing 43 when moving from the bearing 43 to the next inner bearing 43, it can be smoothly passed by the R surface and is not caught.

(4) In FIG. 10, the cleaned workpiece W is discharged from the outlet 3 to the unloading tank 5, and the conveying jig 18 is removed from the discharged workpiece W. This conveying jig 18 is repeatedly used for conveying the workpiece W.

[Other embodiments]
(1) FIGS. 11 and 12 show modified examples of the conveying jig 18. Similar to the structure shown in FIGS. 7 and 8, the upper jig member 72 is composed of an elongated upper jig member 72 and an elongated lower jig member 73, and a plurality of cylindrical protrusions 74 are formed on the lower jig member 73. A plurality of circular fitting holes 76 are formed in the jig member 72. In addition to these configurations, the upper surface of the lower jig member 73 has a straight line extending in the jig member length direction at the center of the left and right width. A linear step groove 80 is formed, and a linear fitting groove 81 into which the step portion 80 is fitted is formed on the lower surface of the upper jig member 72. Further, anti-slip tapes 75 and 77 having a high friction coefficient are attached to the left and right sides of the step 80 and the left and right sides of the fitting groove 81.

  The cylindrical protrusion 74 and the fitting hole 76 are formed on the upper surface of the stepped portion 80 and the bottom surface of the fitting groove 81, respectively.

  When the workpiece W is clamped by the transfer jig 18 of the modified example, as shown in FIG. 12, the left and right edges of the workpiece W are brought into contact with one end surface of the step portion 80 in the left-right direction. The relative positioning of the workpiece W and the conveying jig 18 is performed. Further, the positioning between the upper and lower jig members 72 and 73 is performed not only by the fitting structure of the cylindrical protrusion 74 and the fitting hole 76 but also by the fitting of the stepped portion 80 and the fitting groove 81. The jig members 72 and 93 are firmly coupled.

(2) In the example of FIG. 1 and the like, a cleaning tank having cleaning liquid nozzles 12 and 13 is used as a surface treatment tank. However, a plating tank in which a plating solution for electroless plating or electroplating is stored, etching Also, the present invention can be applied to workpiece conveyance in a chemical tank in which a chemical used for peeling or developing is stored.

(3) Although a printed circuit board is mainly used as the type of workpiece, the present invention is particularly suitable for conveying a surface treatment such as a flexible substrate or an ultrathin plate having a thickness of 0.06 mm or less.

(4) FIG. 13 is a modified example of the support structure of the transport roller pair 10. Compared with the structure of FIG. 3, the inner bearing 43 (FIG. 3) is omitted, and the transport roller shaft 21 is placed on the inner support wall 41. , 22 is directly supported.

(5) In addition to the structure in which the guide tape 60 is attached to the inner surface of the inner bearing 43 in the left-right direction as the conveyance guide, a single guide plate that extends over substantially the entire length of the conveyance path can be disposed. Of course, this guide plate is a member having a low friction coefficient and a smooth surface, and a member having high durability and chemical resistance. It is also possible to use the inner bearing 43 itself as a conveyance guide without providing the guide tape 60 or the guide plate.

(6) As shown in FIGS. 7 and 8, each jig member 72 is replaced with a non-slip tape 75, 77 having a high friction coefficient on the holding surface of each jig member 72, 73 of the conveying jig 18. , 73 can be provided with fine irregularities, a large number of fine particles can be attached, or the surface roughness can be increased (roughened) to exhibit an anti-slip function.

(7) FIG. 14 shows a transport method that does not use a transport jig. FIG. 14 is an enlarged cross-sectional view similar to FIG. 2, and the same components as those in FIG. In the conveying method shown in FIG. 14, both end portions in the width direction of the workpiece W are directly sandwiched and conveyed by the upper and lower conveying rollers 15 and 16. Except not using a conveying jig, it is the same as the method of FIGS. 1-13, and there exists the same effect. This method is suitable for conveying a highly rigid workpiece W having a thickness of, for example, 500 μm or more.

(8) In the example of FIG. 1 and the like, the clamping pressure is set for all of the upper and lower conveying rollers 15 and 16, but the setting of the clamping pressure is applied only to some of the conveying rollers 15 and 16. You can also. For example, the conveyance roller pair 10 for which the clamping pressure is set can always be in contact with the conveyance jig or the workpiece at least two pairs.

[Experimental example]
In order to prove the effect of the present invention, the following experiments 1 and 2 were performed.
(Experiment 1)
15 shows a schematic plan view of the experimental apparatus of Experiment 1, and FIG. 16 shows the experimental results using the experimental apparatus of FIG. This experiment 1 is an experiment demonstrating that the workpiece W is attracted to one conveyance guide 60 side by making a difference in the clamping pressure between the left and right conveyance roller devices 11. Specifically, the relationship between the clamping pressure difference between the left and right conveying roller devices 11 and the amount of movement of the workpiece W in the width direction is obtained by experiments.

  15, the experimental apparatus basically includes a pair of left and right inclined conveying roller devices 11 having the same structure as in FIGS. 1 to 13, and the same components as those in FIGS. 1 to 13 are the same. The sign is attached. Further, only one pair of transport roller pairs 10 is displayed, and the rest are omitted.

In FIG. 15, the experimental conditions are as follows.
(1) The clamping pressure of the left conveying roller device 11 is fixed to 50 N, and the clamping pressure of the right conveying roller device 11 is lower than the clamping pressure of the left conveying roller device 11 and is between 25 N and 47 N. Change to 5 levels.

(2) At the loading position (LP) of the workpiece W, the distance B1 from the left conveyance guide (guide tape) 60 to the left end of the left conveyance jig 72 (73) is set to 6 mm.

(3) The conveyance distance A of the workpiece W is 3 m.

(4) The thickness of the workpiece W is 50 μm.

(5) After transporting the distance A from the loading position LP to the unloading position ULP, the amount (distance) B2 by which the workpiece W has moved to the left side is measured.

(6) The conveyance experiment is repeated 5 times, and the average value is plotted in the table of FIG.

(Experiment 2)
FIG. 17 shows a schematic cross-sectional view of the experimental apparatus of Experiment 2, and FIG. 18 shows the experimental results using the experimental apparatus of FIG. This experiment 2 is an experiment in which shower water is applied to both the front and back surfaces of the workpiece W and the amount of deflection δ at the center in the width direction of the workpiece W is measured during the workpiece conveyance.

In FIG. 17, the experimental conditions are as follows.
(1) The clamping pressure of the left conveyance roller device 11 is fixed to 50 N, and the clamping pressure of the right conveyance roller device 11 is lower than the clamping pressure of the left conveyance roller device 11 and is 5 to 25 N to 47 N. Change to stages.

(2) During work transfer, 12 megapascals of shower water is sprayed on the front and back surfaces of the work W.

(3) The conveyance distance A of the workpiece W is set to 3 m (see FIG. 15).

(4) The thickness of the workpiece W is 50 μm.

(5) After conveying the distance A from the loading position LP to the unloading position ULP in FIG. 15, the amount of deflection δ at the center in the width direction of the workpiece W is measured as shown in FIG.

(6) The conveyance experiment is repeated 5 times, and the average value is plotted in the table of FIG.

(Conclusion based on the experimental results of Experiment 1 and 2)
(1) As shown in FIG. 16, the lower the roller clamping pressure on one side (right side), the greater the movement amount B2 of the workpiece W in the width direction per conveyance distance. On the other hand, as shown in FIG. It can be seen that the amount of deflection δ at the center of the workpiece W also increases.

(2) Considering the results of Experiments 1 and 2, the ratio of the roller clamping pressure (N) of the left and right conveying roller devices 11 is about left: right = 1: 0.9 to 1: 0.4. In this range, the workpiece W is moved quickly in the width direction, and the deflection amount δ at the center of the workpiece W can be kept small.

(3) The work is crushed in consideration of factors such as the roller clamping pressure of the left and right transport roller devices 11, the thickness of the work, the outer diameter of the work, the nature of the work, the shower pressure, and the presence or absence of a transport jig. In addition, the workpiece is set within a range in which the workpiece does not slide off the conveying rollers 15 and 16.

1 Cleaning tank (an example of a surface treatment tank)
DESCRIPTION OF SYMBOLS 10 Conveyance roller pair 11 Conveyance roller apparatus 15 Upper conveyance roller 16 Lower conveyance roller 18 Jig for conveyance 45 Gap adjustment mechanism 60 Guide tape (conveyance guide)
72 Upper jig member 73 Lower jig member 74 Cylindrical protrusion 75, 77 Non-slip tape 76 Fitting hole 80 Step part 81 Fitting groove W Workpiece

Claims (4)

A plurality of conveying roller pairs, each of which includes a pair of conveying rollers that are vertically opposed to each other with a predetermined interval in the workpiece conveying direction, are provided on both sides in the width direction of the workpiece conveying path. the axial, viewed from above, the inner side of the width direction is inclined to come to the conveying direction, Ri by the above two conveying rollers device grips the both ends in the width direction of the rectangular shaped workpieces from above and below in the work transfer method for the surface treatment tank for transporting a workpiece in horizontal state,
Wherein among both sides in the width direction of the workpiece conveying path, at least one, conveying guides extending workpiece transfer path and the flat row is laid,
Of the pair of transport roller devices, the roller clamping pressure of the transport roller device on the side where the transport guide is disposed is set higher than the roller clamping pressure of the other transport roller device,
Due to the difference in the roller clamping pressure, the workpiece is drawn toward the conveyance guide side, pressed against the conveyance guide, guided in the conveyance direction,
The both ends of the workpiece in the width direction are sandwiched from above and below by a conveying jig over the entire length of the workpiece in the conveying direction,
Each of the conveying jigs is sandwiched from above and below by a pair of conveying rollers of the corresponding conveying roller device,
A method of conveying a workpiece in a surface treatment tank, wherein the workpiece is conveyed while being pulled outward in the width direction through the two conveying jigs on both sides in the width direction by the rotation of each pair of conveying rollers . Both end portions in the width direction of the workpiece arranged rectangular shape horizontal posture from above and below a conveying jig for clamping,
An upper jig member and a lower jig member;
Both jig members have clamping surfaces with a high coefficient of friction that contact the upper and lower surfaces of the end portion in the width direction of the workpiece,
One jig member is formed with a protrusion arranged at an interval in the workpiece conveying direction, and the other jig member is formed with a fitting hole into which the protrusion is fitted.
Each protrusion, conveying jig, characterized by positioning the flat row and conveying direction said edge in contact with the width direction of the edge of the workpiece. In the conveying jig according to claim 2 ,
The protrusion is formed in a cylindrical shape, and the fitting hole is formed in a circular shape. Both end portions in the width direction of the workpiece arranged rectangular shape horizontal posture from above and below a conveying jig for clamping,
An upper jig member and a lower jig member;
Both jig members have clamping surfaces with a high coefficient of friction that contact the upper and lower surfaces of the end portion in the width direction of the workpiece,
One jig member is formed with a stair-like step portion extending over the entire length of the jig member in the workpiece conveying direction, and the other jig member has a fitting groove into which the step portion is fitted. Formed,
The stepped portion is conveyed jig, characterized by positioning the contact with the end edge in the width direction of the edge of the workpiece in the conveying direction and flat row.

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