JPH03297Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a mechanism for preventing warpage of a printed circuit board in an automatic soldering device.

[Conventional technology and problems]

As an automatic soldering device for printed circuit boards, the left and right edges of the printed circuit board are held between the main carriers installed on the left and right sides of each device with the support members provided on the main carriers, and the left and right edges of the printed circuit board are held between them. There are two types of devices: devices that perform various processing steps, and devices that attach a printed circuit board to a carrier and complete soldering by being transported by this carrier.

The latter device is also used for soldering printed circuit boards with relatively large areas by providing a mechanism to prevent warpage of the printed circuit board on the carrier itself. The work of engaging the prevention mechanism with the central part of the front and rear ends of the printed circuit board is complicated and is not desirable in terms of work efficiency.

The former method is relatively efficient as it directly holds the printed circuit board without using a carrier, but it does not have a mechanism to prevent the printed circuit board from warping.
Heating with a preheater, heating at the time of soldering,
In addition, if warpage occurs due to the weight of electrical components attached to the printed circuit board, not only will it be difficult to achieve good soldering, but the printed circuit board may fall off from the device. There were problems such as only small areas could be used.

In order to solve these problems, the applicant proposed a warpage prevention mechanism for printed circuit boards in an automatic soldering machine that does not use a carrier for holding and transporting printed circuit boards, as shown in Japanese Patent Application Laid-Open No. 58-100492. is proposed. However, this device is designed to prevent warping of the printed circuit board by hooking an engaging claw on the lower surface of the center of the front and rear ends of the printed circuit board and pulling it upward. Although this method is effective in preventing downward warping in the center of a large printed circuit board, it cannot deal with it.

[Purpose of invention]

The present invention was devised in view of these circumstances, and it solves the problems of the conventional technology by simple yet rational means, and rationally prevents the center part of the printed circuit board from warping downward. It is an object of the present invention to provide a warpage prevention mechanism that can effectively solder a wide-area printed circuit board and cut lead wire terminals.

[Structure of the idea]

The structure of the present invention that solves the problems of the conventional technology is as follows:
In automatic soldering equipment that does not use a carrier for holding and transporting printed circuit boards, accompanying the main transport body of printed circuit boards during the soldering process that requires prevention of warpage of the printed circuit board and/or within the lead wire terminal cutting process area. A support structure is provided which can be moved back and forth and returned to and returned to by another return carrier, and the support structure has a warp retaining member that can be attached to and separated from the top surface of the printed circuit board, and a warp holding member that is attached to the hole of the printed circuit board. The present invention is characterized in that a warpage prevention mechanism is provided with an engager that is inserted and engaged with the hole and is movable up and down.

[Example] (Figures 1 to 4 a, b, c) The details of the embodiments will be explained with reference to the drawings.

Fig. 1 is an explanatory diagram showing the arrangement of the present invention in an automatic soldering machine, Fig. 2 is a partially cutaway front view of the main part, and Fig. 3 is a partially cutaway front view of the main part showing the state of preventing warpage of the printed circuit board. 4a, b, and c are flowcharts showing the engagement relationship of the warpage prevention mechanism with respect to the printed circuit board, and FIG. 5 is a front view of the main parts of the warpage prevention mechanism that engages with the front and rear edges of the printed circuit board. Fig. 6 is a plan view of the main parts of the above, Fig. 7 is a partially cutaway front view showing the rotation mechanism of the engaging pawl, Fig. 8 is an explanatory view of the operation of the above, and Fig. 9 is the warpage prevention mechanism and the above. FIG. 3 is a side view showing the connection relationship with a printed circuit board.

First, regarding Figures 1 to 4 a, b, and c,
An example will be explained.

Fig. 1 shows a generally known automatic soldering device, in which 1 is a flux application tank, 2 is a preheater for dissipating organic matter in the flux, 3 is a preliminary soldering tank, 4 is a lead wire cutter, and 5 is a flux application tank. 6 is a preheater for dissipating organic matter in the flux, 7 is a main soldering tank, and 8 is a printed circuit board having a hole 8a in the center of the plate surface.The automatic soldering apparatus A is constituted by the above-mentioned mechanism. Also,
9a and 9b are warpage prevention mechanisms for the printed circuit board 8 according to the present invention; one of the warpage prevention mechanisms 9a is disposed within a lead wire terminal cutting process area where prevention of warpage of the printed circuit board 8 is required; The warpage prevention mechanism 9b is arranged within the main soldering process area where it is necessary to prevent the printed circuit board 8 from warping.

Next, the warpage prevention mechanisms 9a and 9b will be explained with respect to the main conveyance bodies that move back and forth within the above-mentioned areas. 10 is a main conveyance body that circulates in the horizontal direction that is separately disposed on both sides of the automatic soldering apparatus A. A large number of support rods 11 of different shapes are attached to the chain block of the main conveyor 10 at appropriate intervals. Gripping portions 12 for gripping both side edges of the printed circuit board 8 are formed at the inner end of the lower side. Since the main carrier 10 equipped with this support rod 11 is already in general use, a detailed explanation thereof will be omitted.
The connecting shafts 13 of each chain block of the main transport body 10 are extended upward, and a connecting plate 14 is loosely fitted onto each extended connecting shaft 13 with a rotation preventing structure so as to be movable up and down. There is.

Next, the configuration of the warpage prevention mechanisms 9a and 9b will be explained. Reference numeral 15 denotes a horizontally held base plate, and this base plate 15 is engaged with a guide rod 16 that is pivoted parallel to the conveyance direction of the main conveyor 10 with respect to the automatic soldering apparatus A. It is configured to be able to reciprocate along this guide rod 16 with a constant stroke, that is, from the upper side to the lower side of the solder baths 3 and 7.

Furthermore, excitation magnets 17 and 18 are provided at the lower inner end and lower outer end of the base plate 15, respectively, and correspond to the upper side of the connecting plate 14. When one of the excitation magnets 17 is excited, The connecting plate 14 is lifted up and attracted to this, the base plate 15, more specifically, the entire warpage preventers 9a and 9b are moved together with the main conveyor 10, and the excitation magnet 17
When the excitation of the excitation magnet 18 is cut off and the excitation magnet 18 of the other is excitation, the return conveyor 19 of the anti-warpage mechanisms 9a and 9b, which is constantly circulating in the vertical direction.
is attracted to this excitation magnet 18, and the anti-warpage mechanisms 9a and 9b are configured to return to their original positions. The respective excitation magnets 17 and 18 can be switched instantaneously by an electric circuit.

A guide body 20 having a groove 20a is vertically disposed on one of the base plates 15, and an elevating body 21 having a protrusion (not shown) that fits into the groove 20a of the guide body 20 is vertically mounted on the guide body 20. is movably provided, and
A cylinder 25 is provided with lifting and lowering speed regulators 23 and 24 at the end of a connecting rod 22 protruding from the outside of this elevating body 21, and is attached to the device.
are connected to each other, and the elevating body 21 is moved up and down by a predetermined stalk along the guide body 20 by the elevating action of the cylinder 25.

A telescopic rod 26 that expands and contracts in the horizontal direction is provided on the inner surface of the elevating body 21, and at the tip thereof,
A cylinder 29 with raising and lowering speed regulators 27, 28 is mounted vertically. At one end of the lower end of the actuating rod 30 of this cylinder 29,
A "shaped warp holding member 31 is attached to the top surface of the printed circuit board 8, and
The lower end of the actuating rod 30 is pivotally supported by the upper end of a vertical rod of a downwardly shaped engager 32 along the central axis of the actuating rod 30.
The lower end of a connecting rod 34 of a solenoid 33 attached to the actuation rod 30 is connected to the tip of the horizontal rod. The warpage prevention mechanisms 9a and 9b are constructed with the above-mentioned comprehensive structure.

[Operation] (First Embodiment) The operation of the present invention will be explained with reference to FIGS. 4a, b, and c.

When the printed circuit board 8 enters from the direction of the arrow in FIG. 1, the tip of the printed circuit board blocks the optical axis of the phototube devices (not shown) disposed above and below, and the optical axis is set in advance electrically, that is, by a shift register circuit. When the printed circuit board 8 advances by the specified distance, the excitation magnet 17 is excited, and the connecting plate 14 of the main carrier 10 is lifted up and attracted to this excitation magnet 17.
A pair of left and right warpage prevention mechanisms 9a move together with the main transport body 10. Immediately, the cylinder 29 is actuated, the actuating rod 30 is lowered, and the engager 32 provided at the lower end of the actuating rod 30 is inserted into the hole 8a of the printed circuit board 8.
The lower end of the warpage pressing member 31 provided on one side of the lower end of the printed circuit board 8 comes into contact with the upper surface of the printed circuit board 8. (Figure 4a
→b) In response to the signal that this state is completed, the solenoid 33 provided on the actuating rod 30 is energized, the connecting rod 34 is pulled upward, and the engaging element 32 is rotated as shown in Fig. 4c. The printed circuit board 8 is held by the interlocking members 32, and the central portion of the printed circuit board 8 is restrained by the cooperation with the warpage suppressing member 32, thereby preventing the printed circuit board 8 from warping.

When the predetermined preliminary soldering process and the lead wire terminal cutting process are completed, the action of the solenoid 33 is released, the engagement element 32 is in the state shown in FIG.
0 rises and assumes the attitude shown in Figure 4a. At this point, the excitation magnet 17 is de-energized, and at the same time, the other excitation magnet 18 is excited, and the base plate 15 and the return carrier 19 are connected via this excitation magnet 18, and the sled that has played its role is The prevention mechanism 9a returns to its original position, and the excitation magnet 18 is de-energized.

On the other hand, after the soldering process and the cutting process of the lead wire terminals have been completed, the printed circuit board 8 has a warpage prevention mechanism 9b waiting on the lower side with the same effect as described above.
is in effect, and warpage is prevented until the main soldering process is completed.

[Example 2] (Figures 5 to 9) This example is based on the patent application filed by the applicant
This embodiment has the same structure as that shown in Publication No. 58-100492, in which the center portions of the front and rear edges of the printed circuit board 8 are restrained to prevent warping. This is to be used in conjunction with the examples. Therefore, since most of the mechanisms are the same as those of the first embodiment, the different configurations will be supplementarily explained.

Above the tip of the telescoping rod 26, a cylinder 37 equipped with rising and descending speed regulators 35, 36 is installed vertically, and below the tip of the telescoping rod 26, a cylinder 38 is attached to the cylinder 37. It is installed vertically on the same axis. In this embodiment, warp prevention bodies 9c and 9b restrain the front and rear edges of the printed circuit board.
A pair of anti-warpage mechanisms are configured.

As is clear from FIGS. 5 and 7, the cylindrical body 38 has a rod 4 provided with a fan-shaped engaging pawl 39 at the lower end.
The upper part of the rod 40 is rotatably attached, and the hole 41 provided in the upper part of the rod 40 has a
The end of the rod 42 of the cylinder 37 is rotatably fitted. A pin 43 is provided at the end of the rod 42, and this pin 43 connects to a helical groove 44 formed around the half circumference of the hole 41 of the rod 40.
Moreover, since the rod 42 of the cylinder 37 has a key groove structure to prevent rotation with respect to the cylindrical body 38, the vertical movement of the rod 42 causes the pin 43 and the spiral groove 44 to rotate. Due to the related structure, the rod 40 with the engaging pawl 39 is configured to reciprocate through 180 degrees.

[Function] (Second Embodiment) The front and rear warp prevention bodies 9c and 9d are constructed as described above. Next, the function of this embodiment will be explained with reference to FIG. 8. On the upper side of automatic soldering device A, they are in the relative positions as shown in the figure.

Then, the printed circuit board 8 enters from the direction of the arrow,
When the optical axes of the phototube devices 45 arranged above and below are blocked by the tip a of the printed circuit board 8, and the printed circuit board 8 advances by a distance _L1 set in advance by an electrical, that is, a shift register circuit, the prevention occurs. The excitation magnet 17 of the body 9c is excited, and the connecting plate 14 of the main transport body 10 is connected to the excitation magnet 1.
7, and the warpage prevention body 9c moves together with the main conveyance body 10. Immediately, the rod 42 of the cylinder 37 descends, and by the action of the pin 43 provided on the rod 42 and the spiral groove 44 of the rod 40, the rod 40 is rotated 180 degrees while moving the rod 40 through a constant stroke (L ₁ . . . ). 100 mm) to bring the engaging claws 39 into contact with the lower surface of the printed circuit board 8, thereby correcting warping caused by the heating of the preheater and the weight of the attached electrical components.

Then, the rear end b of the printed circuit board 8 passes through the optical axis of the phototube device 45, this optical axis is electrically connected, and the printed circuit board 8 is further moved by a distance L ₃ set in advance by the electrical, that is, the shift resist circuit. As it advances, one magnet 17 of the warp preventer 9d is energized, and the warp preventer 9d is connected to the main conveyor 10 in the same way as described above, and at the same time as it starts to move, the warp preventer 9d is moved by the action of the cylinder 25. is H ₂
stroke and then another cylinder 3
H ₁ while rotating the rod 40 by 180° by the action of step 7.
8, and touches the lower side of the rear end of the printed circuit board 8 to correct the warpage.

In this way, when the preliminary or main soldering work is completed with the leading and rear end central portions of the printed circuit board 8 supported by the engaging claws 39, the warp prevention body 9
The rods 40 c and 9d are simultaneously lowered by _H1 under the action of the cylinder 37 and simultaneously rotated 180 degrees under the action of the spiral groove 44, thereby causing the engaging pawl 39 to escape out of the silhouette range of the printed circuit board 8.

Next, at the rising end where the warp preventers 9c and 9d are simultaneously raised by a distance of H ₂ by the action of the other cylinder 25, the excitation magnet 17 is de-energized, and the warp preventers 9c and 9d are connected to the main transport body 10. Insulated. After this insulation, the excitation magnet 18 is switched and excited at the same time as the excitation magnet 17 is insulated, and the warp preventers 9c and 9d are simultaneously connected to the return carrier 19.
, and is returned to its original position, more specifically, to the upper side of the solder baths 3 and 7.

That is, when one of the warpage prevention bodies 9d reaches the home position, the excitation magnet 18 of this body is released, and the warpage prevention body 9d stops in the same position. That is, the state is shown in FIG. The other anti-warpage body 9c further continues to return, and at the same time as the excitation magnet 18 is de-energized and stops at the position _L2 in _FIG . , the following work posture is adopted.

By the same operation and the operation of the first embodiment described above, as shown in FIG. 9, warpage of the printed circuit board is corrected and prevented in a self-continuous manner. In this embodiment, _L2 is set to be approximately the same length as the printed circuit board 8.

〔effect〕

As described above, according to the configuration of the present invention, the following effects can be obtained.

(a) Utilizing the hole formed in the center of the printed circuit board, warpage in the center of the large printed circuit board, which could not be achieved with conventional technology, can be reasonably prevented, resulting in highly reliable leads. Cutting and soldering of wire terminals can be performed.

(b) An automatic soldering device that does not use a carrier, which could conventionally only be used for small-area printed circuit boards, can now be used to solder large printed circuit boards, thereby increasing the effectiveness of the device.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing the arrangement of the present invention in an automatic soldering machine, Fig. 2 is a partially cutaway front view of the main part, and Fig. 3 is a partially cutaway front view of the main part showing the state of preventing warpage of the printed circuit board. Figures 4a, b, and c are flowcharts showing the engagement relationship of the warpage prevention mechanism with the printed circuit board, and Figure 5 is a front view of the main parts of the warpage prevention mechanism that engages with the front and rear edges of the printed circuit board. Fig. 6 is a plan view of the main parts of the above, Fig. 7 is a partially cutaway front view showing the rotation mechanism of the engaging pawl, Fig. 8 is an explanatory view of the operation of the above, and Fig. 9 is the warpage prevention mechanism and the above. FIG. 3 is a side view showing the connection relationship with a printed circuit board. DESCRIPTION OF SYMBOLS 1... Automatic soldering device, 9a, 9b... Warpage prevention mechanism, 10... Main conveyance state, 19... Return conveyance state, 29... Cylinder, 30... Actuation rod,
31... Warp holding member, 32... Engagement element, 33
... Solenoid, 34... consecutive rods.

Claims (1)

[Scope of claim for utility model registration] (a) Automatic soldering equipment that does not use a carrier for holding and transporting printed circuit boards, (b) Soldering processes that require prevention of warpage of printed circuit boards, and/or lead wire terminals (c) A support structure is provided that moves back and forth along with the main transport body for the printed circuit board within the cutting process area, and is returned and returned to the main transport body by another return transport body; An automatic soldering device characterized by having a warp prevention mechanism that is movable up and down, including a warp holding member that can be brought into and out of contact with the upper surface, and an engaging element that is inserted into and engaged with a hole in a printed circuit board. Warpage prevention mechanism for printed circuit boards.