JP2006289295A - Viscous material coater and viscous material coating method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a viscous material coating method, which can secure a coating height with respect to a coating width when coating a viscous material on a material to be coated, and a viscous material coater. <P>SOLUTION: Multiple coating, which coats a viscous material 2b further on a viscous material 2a coated on a body 20 to be coated, is carried out. A coating amount of the viscous material 2b by the second or succeeding coating operation is preferably more than the coating amount of the viscous material 2a by the first coating operation in the multi times coating. A discharging diameter of a nozzle 3 for carrying out the second or succeeding coating operation is preferably smaller than the discharging diameter of the nozzle 3 for carrying out the first coating operation. A nozzle height for carrying out the second or succeeding coating operation is nearly equal to the coating height of the viscous material obtained by the last coating operation. Split discharging may be carried out wherein the nozzle 3 finishing coating is made to move by the determined distance in the direction far from the material 20 to be coated and the viscous material 2 is again discharged from the nozzle 3 at the position after moved. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a viscous material applying apparatus and a viscous material applying method for applying a certain amount of a viscous material on a substantially flat plate-like object. More specifically, for example, the present invention relates to a viscous material coating apparatus and a viscous material coating method used for coating an adhesive on a circuit board when an electronic component is mounted on the circuit board.

  For example, when mounting an electronic component or the like on a circuit board, the viscous material application device is used to apply a viscous material such as an adhesive, cream solder, or silver paste necessary for fixing the electronic component to a predetermined circuit board that is an object to be coated. It is used when applying to the application position. As an example, an adhesive application device 50 as shown in FIG. 6 is used to apply an adhesive on a circuit board. In the figure, an adhesive application device 50 includes an application head 51 for applying an adhesive to an object to be applied, a robot 52 for transporting the application head 51, and an object to be applied holding that carries the object to be loaded into the apparatus. The apparatus 53 and the control apparatus 54 that controls the overall operation are main components. Among these, the robot 52 conveys the coating head 51 in the X direction of the figure by driving the motor 56, and the coated object holding unit 53 conveys the coated object held by the driving of the motor 57 in the Y direction of the figure. To do. By the relative movement of the movement of the coating head 51 in the X direction perpendicular to each other and the movement of the coated body holding portion 53 in the Y direction, the coating head 51 can apply the adhesive to a predetermined position of the coated body. . The movement amount in the X direction of the coating head 51 and the movement amount in the Y direction of the coating object holding portion 53 are controlled by the control device 54.

  FIG. 7 shows the coating head 51 in an enlarged manner. In the figure, an application head 51 includes a nozzle 3 that discharges a viscous material, a discharge unit 61 that pushes out an adhesive from the nozzle 3 by using pressure by compressed air, and a viscous material storage unit 62 that includes a syringe that stores the viscous material. And three sets of the application mechanism unit 1 composed of a combination of an elevating unit 63 that elevates and lowers the nozzle 3. These three sets are merely examples, and other numbers may be used. Among these, in the discharge part 61, compressed air can be supplied into the viscous material storage part 62 via the pipe 67 in accordance with the operation of the valve 66. The elevating unit 63 includes a nozzle selection cylinder 64, a cam 65, and a lever 69 provided with a cam follower 68. The elevating unit 63 and the nozzle 3 can be moved up and down in the Z direction in the drawing.

  The coating mechanism unit 1 configured as described above operates as follows. In FIG. 7, when the valve 66 provided in the discharge unit 61 operates for a predetermined time, compressed air is supplied to the viscous material storage unit 62 via the pipe 67, and the adhesive stored in the viscous material storage unit 62 is Pressed down by pressure, a predetermined amount of adhesive 2 is discharged from the nozzle 3. The operation of the nozzle selection cylinder 64 brings the cam follower 68 of the lever 69 into contact with the cam 65. As the cam 65 rotates, one end of the lever 69 rotates to push down the viscous material storage portion 62 and lower it in the Z direction in the figure. Thereby, the adhesive 2 discharged from the tip of the nozzle 3 comes into contact with the opposing circuit board 20, and the adhesive 2 is applied onto the circuit board 20. After application, the viscous material storage section 62 rises to the original position by the rotation of the cam 65, and one application operation is completed.

  The application state of the adhesive 2 applied on the circuit board 20 can be recognized by the recognition device 60 attached to the application head 51. Based on the recognition information input from the recognition device 60, the control device 54 (see FIG. 6) determines whether or not the application state satisfies a predetermined specification. Usually, the adhesive 2 is trial-tested in advance, and after the application state is confirmed, the adhesive application operation to the continuous circuit board 20 is performed. It should be noted that the application height of the applied adhesive 2 can be measured by using the recognition device 60 as a three-dimensional sensor such as a laser.

  In the adhesive application device 50 according to the above-described configuration, the adhesive 2 stored in the viscous material storage unit 62 is pushed out by the action of compressed air. The amount may not be stable. A viscous material coating apparatus that solves this problem has been proposed (see, for example, Patent Document 1). 8 and 9 show the contents disclosed in Patent Document 1. FIG. Among these, FIG. 8 shows one main part of the coating mechanism 1 taken out of the coating head, and FIG. 9 shows the main part centering on the part in the circle I shown in FIG. This is an enlarged view.

  In FIG. 8, an application mechanism unit 1 is rotatably fitted in an adhesive application member 4 provided with a nozzle 3 for discharging an adhesive, and a hollow portion in the longitudinal direction (vertical direction in the figure) of the adhesive application member 4. Main components are a discharge shaft 5 to be discharged, an upper rotating device 6 that rotates the discharge shaft 5 about its axis, and an adhesive supply device 8 that supplies the adhesive 2 to the adhesive application member 4. It is said. Among these, the adhesive supply device 8 includes a syringe 9 that houses the adhesive 2 therein, an adhesive supply pipe 18 that guides the adhesive 2 in the syringe 9 to the adhesive application member 4, and an adhesive in the syringe 9. A compressed air supply unit 32 for supplying compressed air into the syringe 9 in order to push 2 out to the adhesive supply pipe 18. This compressed air is for feeding the adhesive 2 to the adhesive application member 4 against the viscosity of the adhesive 2, and the discharge of the adhesive 2 from the nozzle 3 is caused by the rotation of the discharge shaft 5 described later. Done.

  In order to rotate the discharge shaft 5 by driving the rotating device 6, the connecting shaft 12 for rotation passes through the hollow portion of the spline shaft 23 and is slidable in the axial direction and is rotatable about the axis. A moving member 24 is fixed to the outer peripheral surface of the spline shaft 23, and for example, an elevating part 63 shown in FIG. 7 is engaged with the moving member 24 to drive the spline shaft 23 in the vertical direction in the figure. The stroke of the vertical movement at this time is indicated by the width between a two-dot chain line 35 (upper) and a solid line 36 (lower) in the drawing. As a result of the vertical movement of the adhesive application member 4, the adhesive can be applied to the circuit board 20 when the nozzle 3 attached to the adhesive application member 4 is lowered.

  A spline housing 25 is provided on the outer peripheral surface of the lower end portion of the spline shaft 23. The spline housing 25 supports the spline shaft 23 so as to be slidable in the axial direction, and rotationally drives the spline shaft 23. Therefore, the spline housing 25 is supported by the frame member 29 of the adhesive application device via the bearing 26. A pulley 27 is attached to the spline housing 25 and is driven to rotate by a driving device (not shown). By this rotation, the spline shaft 23 is rotated around the axis, and the adhesive application member 4 coupled to the spline shaft 23 is rotated. For this reason, the nozzle 3 is rotated. The rotation of the nozzle 3 is for avoiding interference with a mounting component by a nozzle stopper described later.

  The adhesive application member 4 is provided with a rotation restricting structure 40, and the adhesive supply pipe 18 is joined to the rotation restricting structure 40. The adhesive application member 4 rotates the nozzle 3 about the axis, but the adhesive supply pipe 18 is regulated at a fixed position by the rotation restricting structure 40, so that the adhesive supply pipe 18 is not swung around.

  In the enlarged view of FIG. 9, the rotation restricting structure 40 is provided with a guide roller 43. The guide roller 43 fits into a guide groove 45 provided in the frame member 29, and even when the adhesive application member 4 rotates, it rotates. The rotation of the movement restricting structure 40 is prevented to prevent the adhesive supply pipe 18 from touching. On the other hand, when the adhesive application member 4 moves up and down, the guide roller 43 slides in the guide groove 45 and guides the vertical movement of the rotation restricting structure 40.

  The adhesive application member 4 is preferably provided with a nozzle stopper 19 adjacent to the nozzle 3 and extending substantially in parallel. The nozzle stopper 19 projects downward slightly longer than the nozzle 3, and when the tip 19 e of the nozzle stopper 19 abuts on the surface of the circuit board 20 (not shown), the circuit board 20 and the tip 3 e of the nozzle 3 A gap is formed between them. This gap is set to an optimum interval for applying the adhesive discharged from the tip 3e of the nozzle 3 to a predetermined position of the circuit board 20 as a lump of adhesive having a predetermined application diameter. Since the nozzle stopper 19 is in direct contact with the circuit board 20, when there is an adjacent component already mounted on the circuit board 20, the tip 19 e may interfere with the component and cause a problem such as crushing. . Alternatively, when there is an uneven portion such as a terminal on the circuit board 20, it becomes impossible to obtain an optimum interval for the application by contacting the uneven portion. Therefore, the nozzle stopper 19 can rotate around the nozzle 3 together with the nozzle 3 via the pulley 27 (see FIG. 8) as described above, and is configured to avoid interference with the adjacent parts.

  The upper end of the discharge shaft 5 is connected to the rotation connection shaft 12 so as to be relatively movable in the axial direction, and transmits the rotation drive of the rotation connection shaft 12. A screw-like screw part 11 is formed at the lower end of the discharge shaft 5. Corresponding to the upper end part 11 a of the screw part 11, an adhesive supply passage 16 opens in the adhesive application member 4. The passage 16 communicates with an adhesive supply pipe 18 via a fixture 17, and is connected to a syringe 9 (see FIG. 8) provided in the adhesive supply device 8 so that the adhesive 2 stored in the syringe 9 is supplied. The When the discharge shaft 5 is driven to rotate about its axis, the adhesive 2 supplied to the upper end portion 11 a of the screw portion 11 is moved along the screw groove of the screw portion 11 in the direction of the other end portion 11 b of the screw portion 11. Sent to. The nozzle 3 is formed coaxially with the discharge shaft 5 in the adhesive application member 4, and the adhesive 2 sent to the other end 11 b of the screw part 11 is further sent into the nozzle 3, and the nozzle 3 The tip 3e is discharged. Thus, since the amount of the adhesive 2 discharged according to the rotation of the screw part 11 is determined, it is possible to apply a stable amount of adhesive regardless of the remaining amount of the adhesive in the syringe 9.

A method of directly attaching the adhesive supply pipe 18 to the adhesive application member 4 without providing the rotation restricting structure 40 is also disclosed (see, for example, Patent Document 2). FIG. 10 shows an outline thereof. The adhesive supply pipe 18 is inserted into the connecting portion 4a of the adhesive application member 4, and the rotation applying structure 40 is not provided in the adhesive application member 4. For this reason, although the adhesive application member 4 rotates and the adhesive supply pipe 18 is swung, the height of the syringe 9 and the connecting portion 4a, and the rotation center of the syringe 9 and the adhesive application member 4 are reduced. By appropriately selecting the distance D and the material of the adhesive supply pipe 18, the adhesive supply pipe 18 has a structure that can sufficiently withstand swinging if the rotation range is up to ± 90 degrees. Other configurations are the same as the viscous material application mechanism shown in FIGS.
JP 11-276963 A JP 2002-239435 A

  Incidentally, FIG. 11A schematically shows the state of the adhesive 2 applied on the circuit board 20 using the various viscous material discharge devices as described above. The left side shows the state of the adhesive 2 applied to the circuit board 20, and the right side shows the state where the chip component 10a is applied on the adhesive 2 applied in the subsequent component mounting process. In this way, when a part of the component 10 a comes into contact with the adhesive 2, the component 10 a is joined to the circuit board 20 via the adhesive 2.

  In contrast, in FIG. 11B, for example, a granular solder 15 is arranged between the component 10b and the circuit board 20 with respect to the component 10b having a terminal such as a BGA (Ball Grid Array) shown on the right side of the drawing. Shows the case. The adhesive 2 is used to fix the component 10b at a predetermined position so that the component 10b does not move and drop off until the granular solder 15 is melted and joined in the reflow process after the component is mounted. In this case, since the granular solder 15 is interposed in the middle, a gap is generated between the component 10 b and the circuit board 20. A typical size of the granular solder 15 is about 1.3 mm in diameter. For this reason, in order to maintain the component 10b in a predetermined position, the application height of the adhesive 2 must be increased to a size of about 1.3 mm or more of the granular solder 15 as shown on the left side of the drawing. Hereinafter, the outer peripheral diameter of the applied adhesive is referred to as application width w, and the height is referred to as application height h.

  However, even if the discharge amount of the adhesive 2 is increased in order to increase the coating height h, the adhesive 2 generally tends to spread in the width direction (direction parallel to the substrate), and the height direction (perpendicular to the substrate). Direction) is hardly seen. For this reason, if the discharge amount is increased so as to increase the coating height h, the coating width w increases as the discharge amount increases, and problems such as adverse effects on adjacent components tend to occur. Further, the adhesive 2 discharged in a large amount clings around the tip 3e of the nozzle 3, and when the nozzle 3 next moves up and moves, the excess adhesive 2 is dragged by the nozzle 3 and falls down. Similarly, there is a possibility that the adjacent parts may be adversely affected. Thus, in the past, it has been the actual situation that an effective measure for ensuring a sufficient coating height h when applying a viscous material has not been found.

  As described above, the present invention eliminates the problems in the prior art as described above, and when applying the viscous material on the material to be applied, the viscosity capable of sufficiently securing the application height with respect to the application width. An object is to provide a material application method and a viscous material application apparatus.

  The present invention solves the above-mentioned problems by providing a viscous material application method and a viscous material application device that apply a plurality of times to apply the viscous material on the viscous material applied on the material to be applied. More specifically, the following contents are included.

  That is, one aspect according to the present invention is a viscous material application method in which a viscous material is ejected from a nozzle and applied onto an object to be coated, and a desired application height of the applied viscous material is obtained. The present invention relates to a method for applying a viscous material, characterized in that the application is performed a plurality of times by applying the viscous material further on the viscous material applied on the body.

  In the above-mentioned multiple times application, for example, when applying to the same location in two times, use a nozzle having a nozzle diameter that is smaller than, for example, about half of the nozzle diameter when the application operation is performed only once. Is desirable.

  In the plurality of times of application, the non-contact height, which is the height from the surface of the material to be applied, of the nozzle that performs the second and subsequent application operations is substantially equal to the application height of the application viscous material obtained by the immediately preceding application operation. It is preferable to do. In order to execute this, the coating height of the coating viscous material obtained by the immediately preceding coating operation can be measured, and the non-contact height at the subsequent coating can be controlled to be substantially equal to the measurement result. .

  Another aspect of the present invention is a viscous material application method in which a viscous material is discharged from a nozzle and applied onto an object to be coated, and the application is finished in order to obtain a desired application height of the applied viscous material. The present invention relates to a method for applying a viscous material, wherein the nozzle is moved by a predetermined amount in a direction away from an object to be coated, and the viscous material is discharged again from the nozzle at a position after the movement. Alternatively, the viscous material can be discharged continuously or intermittently during the movement of the nozzle.

  According to still another aspect of the present invention, there is provided an application mechanism comprising a combination of a nozzle that discharges a viscous material, an elevating unit that raises and lowers the nozzle, a viscous material storage that stores the viscous material, and a discharge unit that discharges the viscous material from the nozzle. A coating head having a plurality of sections; a robot that transports the coating head; and a coated body holding section that carries and holds the coated body, and discharges the viscous material stored in the viscous material storage section. A viscous material application device that discharges from the nozzle using means and applies the viscous material onto the object to be applied held by the object holding unit, and is opposed to the object to be applied longer than the nozzle Further, nozzle stoppers are provided adjacent to each nozzle so as to contact each of the coated bodies when the viscous material is applied and form a gap with a desired non-contact height between the nozzle and the coated body. The nozzle stopper adjacent to the nozzle provided in at least one application mechanism portion protrudes longer than the corresponding nozzle by the desired non-contact height at the time of the first application in the multiple application, and at least one other The nozzle stopper adjacent to the nozzle provided in the coating mechanism section protrudes longer than the corresponding nozzle by the desired non-contact height at the second and subsequent coatings in multiple coatings. The present invention relates to a viscous material coating apparatus.

  A stopper assembly including a plurality of nozzle stoppers having different heights is provided adjacent to each of the nozzles, and any one nozzle stopper of the stopper assembly is selected in accordance with an appropriate non-contact height at the time of multiple application. A nozzle stopper selection mechanism may be provided.

  Still another aspect according to the present invention is a viscous material application device that similarly includes an application head, a robot, and an object holding unit, and the viscous material application device performs an application operation on the object to be applied. The present invention relates to a viscous material coating apparatus, characterized in that a control device is provided for controlling to perform a coating operation again after the performed nozzle moves in a direction away from the coated body.

  By implementing the viscous material application method and the viscous material application apparatus according to the present invention, it becomes possible to apply a viscous material with a sufficient application height with respect to the application width, for example, a circuit in a temporary state before reflowing. It is more reliable to avoid the displacement and dropout of the mounted components mounted on the board, and it is possible to obtain the effects of avoiding the generation of a defective board and stabilizing the quality of the circuit board. In particular, it is possible to reliably carry out the bonding of components that have a gap with the circuit board via granular solder or the like.

  An embodiment of a viscous material coating method according to the present invention will be described with reference to the drawings. In the following description, an example in which an adhesive is applied onto a circuit board using a nozzle is shown, but in general, the present invention can be widely applied when a viscous material is applied onto a non-applied body. In FIG. 1, (a) on the left schematically shows the application state of the adhesive 2 a applied on the circuit board 20 by the normal application operation by the nozzle 3. When the discharge amount v is about 0.0002 cc, a coating height h1 = 0.6 mm is typically obtained with respect to the coating width w1 = 0.9 mm. It will be understood that variations occur due to the viscosity of the adhesive 2, the wettability of the circuit board 20, and the like.

  On the other hand, in the viscous material application method according to the present embodiment, as shown in (b) in the center of FIG. 1, the adhesive 2a applied on the circuit board 20 is temporarily applied as shown in (a). The adhesive is discharged from the nozzle 3 again, and the adhesive is applied twice, in which a new adhesive 2b is stacked. According to the experiments conducted by the inventors of the present application, even if the same amount of the adhesive 2c as the total discharge amount of the adhesive 2 when applied twice is applied at one time, it is on the right side of FIG. As shown in (c), it is not possible to earn a sufficient coating height h3 simply by increasing the coating width w3. For example, in the above-described example, when the total discharge amount v = 0.0007 cc is applied by one discharge (shown in c), the application width w3 = 1.4 mm and the application height h3 = 0.7 mm. On the other hand, when the discharge amount v is 0.0007 cc by the second application according to this embodiment (shown in b), the application height h2 is about 1.4 mm with respect to the application width w2 = 0.95 mm. be able to. In terms of the aspect ratio r (coating height / coating width), r2 in the case of applying twice (FIG. 1 (b)) versus r1 = 0.5 in the case of applying once (FIG. 1 (c)). = 1.47, and there is a significant difference between the two.

  In addition, according to an experiment conducted by the inventors, when the total discharge amount of the second application is the same amount, the first discharge amount v1 is reduced and the second discharge amount v2 is increased. However, it was found that the coating height h can be obtained more than when the first discharge amount v1 which is the opposite is large and the second discharge amount v2 is small. This is because the applied adhesive 2 tends to spread on a flat surface because the nozzle 3 is close to the planar circuit board 20 during the first application and the adhesive is applied. In the second application, the nozzle 3 approaches the first adhesive 2a that is sharply pointed to apply the adhesive, so that the first adhesive is not spread in the width direction. This is presumably because the second adhesive 2b tends to remain on 2a.

  Next, FIG. 2 shows a non-contact height (hereinafter referred to as “nozzle height”) which is a preferred height from the surface of the circuit board 20 of the nozzle 3 when the viscous material coating method according to the present embodiment is performed. .) H is shown. (A) shown on the left side of FIG. 2 shows the nozzle height H1 when the first adhesive application is performed. When applying the adhesive, as shown in the prior art, first, an appropriate amount of the adhesive 2 is discharged from the tip 3e of the nozzle 3, and then the nozzle 3 descends toward the circuit board 20, and from the tip 3e of the nozzle 3. Application is performed by bringing a part of the protruding side of the protruding adhesive 2 into contact with the circuit board 20. After the application, the nozzle 3 is raised and the discharged adhesive 2 is separated from the tip 3e, and only the adhesive 2a remains on the circuit board 20. The nozzle height H1 in a typical first adhesive application is about 0.2 mm.

  FIG. 2B shows the nozzle height H2 when the second adhesive application is performed. According to experiments conducted by the present inventors, it is found that the height H2 at this time is preferably substantially the same as the application height h1 of the adhesive 2a applied for the first time (H2≈h1). It was. In the above example, it is typically preferable that H2 = 0.7 mm. When H2 is lower than this (when H2 <h1), as shown in FIG. 2 (c), the first application adhesive 2a cannot be crushed to increase the overall application height h. When H2 is higher than this (h1 <H2), as shown in FIG. 2 (d), the bonding with the first coating adhesive 2a becomes insufficient and the adhesive 2b adheres to the nozzle 3 side. If it is taken home as it is, or the second coating adhesive 2b falls as shown in FIG. 2 (e), the entire coating height h cannot be earned.

  Furthermore, according to the experimental results conducted by the inventors of the present application, the discharge port diameter of the nozzle 3 for applying the viscous material is divided into a plurality of times, for example, twice, compared to the discharge port diameter of the nozzle 3 for applying the viscous material only at the first time. It has been found that by reducing the size, there is an effect of increasing the coating height h. More specifically, as a result of performing an experiment using a nozzle a having a discharge port diameter of 0.3 mm and a nozzle b having a discharge port diameter of 0.7 mm, when the nozzle a was applied in two portions, the above-described application width w2 = Although 0.95 mm and coating height h2 = 1.4 mm can be ensured, when the nozzle b having the discharge orifice diameter is applied in two batches, the coating width w2 = 1.3 mm and the coating height The length h2 was 0.9 mm, and it was difficult to achieve the target coating shape.

  As another aspect of the method of applying the viscous material according to the present embodiment, it is considered that the adhesive 2 to be applied for the first time and the second time is applied by changing the viscosity even if the adhesive 2 is the same quality. It is done. That is, the adhesive 2a to be applied for the first time, which tends to have a wide application width w, has a relatively high viscosity, and the adhesive 2b to be applied for the second time has a viscosity that is normally used. Is used. As a result, the spread of the application width w1 of the adhesive 2a applied for the first time can be suppressed, the application amount (discharge amount) v1 can be reduced, and the adhesive 2b applied for the second time can be formed thereon. Even if it is placed, the overall application height h2 can be earned with the strength of the waist due to the high viscosity of the adhesive 2a applied the first time. In addition, although it changes also with various conditions, the typical viscosity of the adhesive agent generally used is about 60 Pas.

  As shown in FIG. 7, a plurality of syringes (viscous material storage portions 62) are usually attached to the application head 51. At least one of the syringes is filled with the adhesive 2 having a high viscosity, and when the application is performed twice, the first adhesive application is performed by the syringe. The application of the adhesive 2 having a different viscosity described above can be performed by performing the second application from another syringe filled with the adhesive 2 having a normal viscosity. Although it has a high viscosity, its properties as an adhesive are the same as those of ordinary ones, and it can be used in the same manner as other syringes 9 when applying a normal adhesive only once. .

  As still another aspect of the method of applying the viscous material according to the present embodiment, in order to obtain a higher application height h, a plurality of times such as the third, fourth,... Adhesive application can be performed. Such multiple application is advantageous in order to obtain a higher application height h, but the application height h is naturally limited depending on the application amount, viscosity, and the like of the adhesive 2. That is, when the coating height h is increased to some extent, the coating height h is reduced by conversely collapse or collapse of the adhesive 2 layer. According to experiments conducted by the inventors of the present application, it has been found that an effect of reliably increasing the coating height h can be obtained up to at least about three stages of coating.

  Next, an embodiment of a viscous material coating apparatus that can be used when the above-described viscous material coating method according to the present invention is performed will be described with reference to the drawings. As described in the section of the prior art with reference to FIG. 9, the adhesive material application member 4 that holds the nozzle 3 used for adhesive application is adjacent to the nozzle 3 substantially parallel to the axis of the nozzle 3. A nozzle stopper 19 is provided. The details are shown in FIG. In the figure, the nozzle stopper 19a provided adjacent to the nozzle 3a that performs the first application is such that the nozzle stopper 19a protrudes by an amount corresponding to the nozzle height (non-contact height) H1 with respect to the opposing circuit board 20. It is configured to When the adhesive is applied for the first time, the nozzle stopper 19a comes into contact with the surface of the circuit board 20, so that the tip of the nozzle 3 has the optimum nozzle height H1. When a further downward pressing force is applied after the nozzle stopper 19a comes into contact, the spring 21 (see FIG. 9) provided on the upper part of the adhesive material application member 4 absorbs the pressing force.

  On the other hand, as shown in each parenthesis in FIG. 3, the difference in the protruding amount of the nozzle 3b that performs the second adhesive application and the corresponding nozzle stopper 19b is an appropriate nozzle height for the second application. It is formed to be H2. As described above, the nozzle height H2 at this time is preferably equal to the first coating height h1. At least one of the plurality of coating mechanisms 1 provided in the coating head 51 has a relationship between the nozzle 3a and the nozzle stopper 19a shown in FIG. 3, and at least the other has a relationship between the nozzle 3b and the nozzle stopper 19b. It is formed to become. By using a combination of the two nozzles 3a (3b) and the nozzle stopper 19a (19b), the optimum nozzle heights H1 and H2 can be obtained in the first and second coating operations. When applying many times, the nozzle stopper 19 protruding from the nozzle 3 by the optimum non-contact height for the third and fourth times may be provided in the same manner.

  4A and 4B show another aspect of the viscous material applying apparatus according to the present embodiment. Both figures are side views of the nozzle 3 viewed from an angle different from 90 °. As described above, when the nozzle stoppers 19a, 19b, etc. having the optimum heights are provided on the adhesive material application member 4, the nozzles 3a, 3b, etc. are dedicated to the first application, the second application, and so on. Generality is lost. In the example shown in FIGS. 4A and 4B, a nozzle stopper selection mechanism that enables the nozzle stopper 19 to be selected and used in order to solve this problem is provided. That is, in both figures, the adhesive material application member 4 is provided with a stopper mounting portion 71, and a stopper assembly 70 provided with a plurality of lengths of nozzle stoppers 19a to 19c is rotatably mounted. The rotating shaft 72 of the stopper assembly 70 is provided with a protrusion 73 that allows the nozzle stoppers 19a to 19c to be selected by rotating the stopper assembly 70.

  A stopper switching shaft (not shown) extending from the viscous material applicator main body side is fitted into the projecting portion 73, and the rotating shaft 72 can be rotated. The nozzle stopper 19 having an optimal protrusion amount can be selected from the stopper assembly 70 that rotates the rotating shaft according to the number of times of application, and can be arranged at a predetermined position. A simple positioning mechanism 74 is provided in the stopper mounting portion 71 so that the selected nozzle stopper 19 is fixed at a fixed position. In FIG. 4 (b), the stopper assembly 70 includes three different nozzle stoppers 19a-19c, but this number is merely exemplary.

  The above description is based on the premise that the nozzle height H is controlled using the nozzle stopper 19, but the nozzle height H is controlled by using a linear scale, a sensor, or the like. There is also a method of controlling the absolute height 3 by the control device 54 (see FIG. 6). This is because the height of the nozzle 3 is calibrated when the machine is started up, and thereafter, the amount of movement in the vertical direction is grasped using a linear scale and a sensor, so that the height of the nozzle 3 is independent of the circuit board 20. Is to control.

  Next, a viscous material application method according to a second embodiment of the present invention will be described. In the method according to the first embodiment, the nozzle 3 is lowered to a preferred non-contact height toward the circuit board 20, and after the first adhesive application is completed, the nozzle 3 is once pulled up, and the nozzle 3 is moved again to the preferred non-contact height. The adhesive is applied for the second time by descending to the contact height. On the other hand, in the present embodiment, the nozzle 3 basically approaches the circuit board 20 only once, and the adhesive is applied a plurality of times while moving the nozzle 3 in the direction away from the circuit board 20. It is assumed that the nozzle 3 performs divided discharge.

  That is, in FIG. 5A, the nozzle 3 is lowered to the non-contact height H1, and a predetermined amount of the adhesive 2a is applied by performing the first application. Next, in FIG. 5B, the nozzle 3 is pulled up from the state of FIG. 5A to the optimum non-contact height H <b> 2 for the second application as indicated by an arrow 13. At this time, the adhesive 2a may once be pulled up from the tip of the nozzle 3 to a height that does not divide, and then lowered to a height H2. As the nozzle 3 moves up, most of the applied adhesive 2a remains on the circuit board 20 side as shown in the figure, and the upper part of the adhesive 2a is constricted. Then, as shown in FIG.5 (c), the adhesive discharge of the 2nd time is performed from the nozzle 3, and the adhesive agent 2b of the 2nd time is apply | coated on the adhesive agent 2a of the 1st time. In the illustrated example of the adhesive application mechanism 1, a predetermined amount of adhesive is discharged by rotating the screw 11.

  According to experiments conducted by the inventors of the present application, this method can provide a coating height h comparable to the two-time coating in the first embodiment, and the same amount of coating can be performed only once in the prior art. An advantage in the coating height was recognized as compared with the case of doing. In the conventional technique, the coating width w tends to be widened by applying a large amount with a low non-contact height suitable for the first application, whereas in the present embodiment, the nozzle 3 is once pulled up. It is considered that the spread of the coating width w on the circuit board 20 is avoided.

  In the viscous material coating apparatus for carrying out the viscous material coating method according to the present embodiment, a control device that enables the height control of the nozzle 3 and the divided discharge control of the adhesive 2 is required. First, regarding the height control of the nozzle 3, it is an easy solution to control the absolute height of the nozzle 3 using a linear scale or a sensor.

  However, nozzle height control using a nozzle stopper 19 as shown in FIG. 3 is also possible. In this case, the nozzle stopper 19 has a protrusion amount adjusted to the first nozzle height H1, and the first adhesive application is performed with the nozzle stopper 19 in contact with the circuit board 20. Since the nozzle stopper 19 cannot be used for the second nozzle height control, a contrivance is required. Since the movement after the nozzle stopper 19 abuts against the circuit board 20 is absorbed by the spring 21 (see FIG. 9), the movement amount of the nozzle 3 and the movement amount of the spline shaft 23 are not necessarily matched. This is because it is not sufficient to detect the upward movement amount of the spline shaft 23 (see FIG. 9) that holds the adhesive material application member 4. As a countermeasure for this, a method of controlling a movement amount of the spline shaft 23 in a locked state by newly providing a lock mechanism (not shown) for temporarily preventing the relative movement between the adhesive material applying member 4 and the spline shaft 23 is considered. It is done.

  In addition, regarding the discharge of the adhesive 2, the current control device 54 does not consider the control that enables the divided discharge as described above, and therefore, it is necessary to cope with the change of the program. However, this is relatively easy because it is sufficient to deal with only software, and no hardware modification is required.

  The viscous material coating method and the viscous material coating apparatus according to the present invention are applied to an industrial field in which a predetermined amount of a viscous material is coated on a flat surface such as a substrate, more specifically, an adhesive on a circuit board when a component is mounted. It can be widely used in the component mounting industrial field where cream solder, silver paste or the like is applied.

It is explanatory drawing which shows the outline | summary of the viscous material application | coating method of embodiment concerning this invention. It is explanatory drawing which shows the other aspect of the viscous material application | coating method shown in FIG. It is a side surface partial enlarged view which shows the outline | summary of the viscous material coating device of embodiment concerning this invention. It is a side surface partial enlarged view which shows the other aspect of the viscous material coating device shown in FIG. It is explanatory drawing which shows the outline | summary of the viscous material application | coating method of other embodiment concerning this invention. It is a perspective view of an adhesive agent coating apparatus. It is a perspective view which shows the coating head used for the adhesive agent coating apparatus shown in FIG. It is a side surface fragmentary sectional view which shows the other viscous agent application | coating mechanism used by a prior art. It is the expanded side surface fragmentary sectional view which expanded the part I shown in FIG. It is the elements on larger scale which show the principal part of the adhesive material application | coating mechanism part of a cloth head. It is side surface fragmentary sectional view which shows the further another adhesive agent application mechanism used by a prior art. It is explanatory drawing which shows the adhesive agent use aspect at the time of mounting components on a circuit board.

Explanation of symbols

1. 1. coating mechanism, 2. adhesive, Nozzle, 4. 7. Adhesive application member, 8. Adhesive supply device Syringe, 10. Parts, 11. 15. Screw part, Granular solder,
19. Nozzle stopper, 20. Circuit board, 50. Adhesive application device, 51. Coating head, 54. Control device, 60. Recognition device, 70. Stopper assembly, 71. Stopper mounting part.

Claims (13)

In the viscous material application method in which the viscous material is discharged from the nozzle and applied onto the substrate,
In order to obtain the desired application height of the applied viscous material, the viscous material is applied on the viscous material applied on the object to be coated, and the viscous material is further applied.   The method for applying a viscous material according to claim 1, wherein the amount of application at the second and subsequent application is larger than the amount of application of the viscous material at the first application.   2. The viscous material application according to claim 1, wherein a discharge port diameter of a nozzle that performs a plurality of times of application is about ½ of a discharge port diameter of a nozzle that is used when a normal one-time application is performed. Method.   The method for applying a viscous material according to claim 3, wherein a discharge port diameter of the nozzle that performs the application a plurality of times is about 0.3 mm.   The method for applying a viscous material according to claim 1, wherein the viscosity of the viscous material applied at the first application is higher than the viscosity of the viscous material applied at the second and subsequent applications.   The non-contact height that is the height from the surface of the coated body of the nozzle that performs the second and subsequent coating operations is approximately equal to the coating height of the coating viscous material obtained by the immediately preceding coating operation, The method for applying a viscous material according to claim 1.   The coating height of the coating viscous material obtained by the immediately preceding coating operation is measured, and the non-contact height at the subsequent coating is controlled to be substantially equal to the measurement result. The method for applying a viscous material according to 1. In the viscous material application method in which the viscous material is discharged from the nozzle and applied onto the substrate,
In order to obtain the desired application height of the applied viscous material, the nozzle after applying the viscous material is moved by a predetermined amount in the direction away from the object to be applied, and the viscous material is discharged from the nozzle again at the position after the movement. A method for applying a viscous material.   9. The method for applying a viscous material according to claim 8, wherein the amount of the viscous material applied after the movement is larger than the amount of the viscous material applied first. In the viscous material application method in which the viscous material is discharged from the nozzle and applied onto the substrate,
In order to obtain the desired application height of the applied viscous material, the nozzle after applying the viscous material is moved away from the object to be applied, and the viscous material is discharged continuously or intermittently during the movement. A method for applying a viscous material. An application head provided with a plurality of application mechanisms comprising a combination of a nozzle that discharges the viscous material, an elevating unit that raises and lowers the nozzle, a viscous material storage that stores the viscous material, and a discharge unit that discharges the viscous material from the nozzle;
A robot that conveys the coating head;
An application body holding unit that carries and holds the application body;
In the viscous material applicator for discharging the viscous material stored in the viscous material storage unit from the nozzle using the discharge means, and applying the viscous material onto the target object held by the target object holding part. ,
Each nozzle stopper protrudes longer than the nozzle in a direction facing the object to be coated, and abuts against the object when the viscous material is applied to form a gap with a desired non-contact height between the nozzle and the object to be coated. Further provided adjacent to the nozzle,
In order to apply the viscous material further on the viscous material applied on the object to be applied, the nozzle stopper adjacent to the nozzle provided in at least one of the application mechanisms is not desired at the first application. The nozzle stopper that protrudes longer than the corresponding nozzle by the contact height and is adjacent to the nozzle provided in at least one other coating mechanism corresponds to the desired non-contact height at the second and subsequent coatings. A viscous material applicator characterized by projecting longer than a nozzle.   A stopper assembly is provided adjacent to each of the nozzles, and the stopper assembly includes a plurality of nozzle stoppers having different heights corresponding to appropriate non-contact heights at the time of multiple application, The viscous material coating apparatus according to claim 11, further comprising a nozzle stopper selection mechanism for selecting a desired nozzle stopper correspondingly. An application head provided with at least one application mechanism comprising a combination of a nozzle that discharges the viscous material, an elevating unit that raises and lowers the nozzle, a viscous material storage that stores the viscous material, and an ejection unit that discharges the viscous material from the nozzle; ,
A robot that conveys the coating head;
An application body holding unit that carries and holds the application body;
In the viscous material applicator for discharging the viscous material stored in the viscous material storage portion from the nozzle using the discharge means, and applying the viscous material on the target object held by the target object holder. ,
A viscous material coating apparatus, comprising: a control device that controls to perform the coating operation again after the nozzle that performed the coating operation on the coated body moves in a direction away from the coated body.

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