JPH0121598Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a printed wiring board commonly used in various electrical products, and when many parts such as various resistors or transistors are attached to the board, the parts inserted through each hole on the board are The present invention relates to a clinch cutter mechanism used to efficiently shear and clinch wire legs to a predetermined length on the back side of a substrate.

Automation of the work of assembling parts onto printed circuit boards has made remarkable progress in recent years, and attempts have been made to mechanically handle the work of inserting various parts, soldering work on the back side, etc.

However, when soldering the wire-shaped legs of each component inserted through each hole on the board to the printed wiring on the back of the board, the condition in which the legs are inserted is a big problem when soldering. Needless to say, it has an impact.

In other words, if the tip of each leg simply protrudes through the printed wiring on the back of the board, the amount of solder that adheres is limited to only the cross-sectional peripheral edge of the leg. Tangential strength is not strengthened very much. However, when the tip of the leg is bent even slightly along the printed wiring on the back of the board and clinched, the solder adheres not only to the raised edge of the leg, but also to the bending of the leg. Since additional solder can be applied along the longitudinal direction by the length of the clinched parts, the mounting strength of each part is greatly improved.

For this reason, the legs of each component have been manually clinched, but this work is not easy because there are a large number of components.

Therefore, in order to eliminate these inconveniences, we
A lead wire cutting and bending mechanism having the structure disclosed in No. 134799 has been developed.

However, when using the above-mentioned conventional cutting and folding mechanism, that is, the clinch cutter mechanism, the cutting blade portion of the fixed knife is subject to severe wear, making it uneconomical to replace the above-mentioned expensive fixed knife at regular intervals. It was hot. In addition, the stroke of the moving knife, which moves forward and backward along the fixed knife, is performed by supplying and exhausting high-pressure air into a hollow chamber partitioned by a piston, and this high-pressure air is actuated electrically. It is supplied by an air valve, but the method of applying electrical signals to the air valve is the actuation signal of the head for inserting the wire-like leg of the component into the printed wiring board, and the insertion of the clinch cutter part into the back side of the printed wiring board. It is necessary to slightly delay the activation signal of the elevator cylinder (not shown), which moves the elevator cylinder diagonally upward toward the wire-shaped leg that has been moved, by a certain period of time, and for this reason, the elevator cylinder itself or the clinch that retreats due to this needs to be delayed by a certain amount of time. A limit switch was provided to be brought into contact when the cutter began to retreat, and the signal from the limit switch was used to operate the air valve for starting the moving knife described above.The durability of the limit switch was poor, and work was interrupted each time to replace it. This was inefficient as they were forced to do so.

Another problem is that it is not possible to finely adjust the delay time as necessary to improve workability, which is related to the length of the legs of the component.

Therefore, in the present invention, in order to solve the above-mentioned problems of the conventional technology, the printed wiring board is
a head part that descends from above to insert the wire-like leg of the component; a clinch cutter part that approaches the lower side of the printed wiring board in synchronization with the descent of the head part; The device comprises a fixed fixed knife for shearing the wire-like foot attached to the part to a predetermined length on the back side of the substrate, and a moving knife that slides along the fixed knife. A delay relay with a built-in delay element equipped with a volume that can adjust the delay time as appropriate is interposed between the actuation signal generation section of the clinch cutter section and the drive solenoid input section of the moving knife, and the The tuxedo knife has a polygonal shape with at least a triangular plane or a circular shape, and is mounted at one end of the elongated hole for inserting the component legs at a position equidistant in the radial direction from the center and rotationally symmetrical to each other. A clinch cutter mechanism has been developed that is characterized by having a plurality of continuous through holes. FIG. 1 shows the structure of a clinch cutter section according to an embodiment of the present invention, which comprises a housing 1, a lid 4, and a piston rod 5 penetrating between the two.
The housing 1 has a hollow chamber 2 open on one side and a fixing base 10 on the opposite side.

Further, the lid body 4 covers one opening surface of the housing 1 via the sealing material 3, and maintains the hollow chamber 2 in an airtight state in relation to the piston rod 5 passing between the two. Furthermore, within the hollow chamber, a piston 7 having a sealing material 7 on its outer peripheral edge is integrally assembled approximately at the center of the piston rod 5 so that it can move within the hollow chamber as the piston rod 5 moves in the axial direction.

Further, the tip of the piston rod 5 protrudes forward from the housing 1 and faces the fixing base 10.

On the other hand, a fixed knife 11 is placed on the fixed base 10. That is, as shown in detail in FIG. 2B, the fixed knife 11 is a blade having a substantially triangular plane and a constant thickness.
The center of each side is curved inward, and a through hole 12 is provided near the corner of each tip, that is, at a position equidistant from the center in the radial direction and rotationally symmetrical to each other.
is provided.

Further, the through hole 12 has a diameter larger than that of the elongated hole 12b for inserting the component leg along the center direction line, and the elongated hole that is opened continuously at the end of the elongated hole 12b near the center of the fixed knife. The elongated hole 12b and the mounting screw hole 12a are designed to serve both as a component leg insertion hole and as a mounting screw hole, respectively.

Note that 13 indicates a positioning hole.

A moving knife 14 is slidably mounted on the upper surface of the above fixed knife 11, and a shearing portion 16 is provided at the tip of the moving knife 14 as shown in FIG.
It has an inclined surface 17 that continues to the shearing portion, and the base thereof has a mounting hole 15 to connect the piston rod 5.
The fixed knife 11 is integrally fixed to the tip of the fixed knife 11, and moves forward and backward from the center of the fixed knife 11 toward the through hole 12 on the upper surface of the fixed knife 11 as the rod 5 moves back and forth.

Reference numeral 19 denotes a holding member, which has a concave groove on its lower surface with sufficient clearance not to obstruct the movement of the moving knife 14, and has a tightening screw 20 inserted from above.
The above-mentioned fixed knife 11 is completely fixed to the upper surface of the fixing base 10 by the positioning pin 21.

In addition, 8 is an adjustment screw 9 attached to the rear end of the piston rod 5, and 22 is a fixing screw for the adjustment screw.
and 23 indicate an air hose.

In the above configuration, the fixed knife 11 shown in FIG. 2B is fixed on the fixed base 10 using the two positioning holes 13 corresponding to the two mounting screw holes 12a, and
The clinch cutter part, which has the remaining through hole 12 and is designed to serve as a component leg insertion hole, is connected to a head part that descends to insert the wire-like leg of the component into the printed wiring board from above. (not shown) is brought close to the lower side of the printed wiring board by a computer control system (not shown), and a moving knife attached to the tip of the clinch cutter part that moves back and forth is driven. When high-pressure air is fed from either one of the air hoses 22 and 23 into the rear chamber of the hollow chamber 2 partitioned by the piston 6, the piston 6 moves forward due to the pressure, and the piston rod 5 moves forward due to the pressure. When the moving knife 14 attached to the tip of the moving knife 14 moves forward toward the through hole 12 and the shearing blade 16 at the tip reaches the end of the through hole 12, the part inserted into the through hole 12 The moving knife 14 continues to move forward, and the inclined surface 17 following the shearing blade 16 bends the legs of the component cut in a certain direction and clinch them. . At the same time as the clinch is completed, the adjustment screw 8 provided at the rear end of the piston rod 5 hits the lid 4, stopping the moving knife 14 from moving forward.

Next, by reversing the air supply direction of the air hoses 22 and 23, the air in the rear chamber of the hollow chamber 2 is released, and at the same time, high-pressure air is supplied to the front chamber, causing the piston 6 to move rearward. As a result, the moving knife 14 can be returned to its original position.

In this case, the moving knife 14
The stroke range in the longitudinal direction can be easily adjusted by once loosening the fixing screw 9 and turning the adjusting screw 8.

Hollow chamber 2 partitioned by the piston 6 described above
In this case, high-pressure air is supplied to the pump by an air valve (not shown). That is, the air valve is operated by an electric signal so as to be able to supply high-pressure air at a constant pressure,
Regarding the application method of the electric signal, the operation signal of the head for inserting the wire-like leg of the component into the printed wiring board, both of which are operated by computer control, and the fixed knife 1 described above are used.
1 and a moving knife 14 are moved diagonally upward and backward toward the wire-like leg of the inserted component on the back side of the printed wiring board. It must be granted after a slight delay of .

Therefore, in the present invention, a delay relay with a built-in delay element is used, and this is used as a head for inserting the wire-like leg of the component into the above-mentioned printed wiring board, and an activation signal generating section of the clinch cutter section. By interposing it between the solenoid input section for driving the moving knife, a signal for starting the moving knife is applied with a certain time delay from the operating signals for the head and the clinch cutter section.

In other words, FIG. 4 shows the electrical connection state of the above-mentioned delay relay. In this embodiment, by applying a current of 24 V to the solenoid 26 for advancing the clinch cutter part from the output board 25, the air valve is connected. (not shown) is opened, thereby sending high-pressure air from either one of the air hoses 22 and 23 into the rear chamber of the hollow chamber 2 partitioned by the piston 6, thereby moving the clinch cutter section forward. start. At the same time, a portion of the drive current is converted into a pulse signal via the resistor 27 and the light emitting diode 28, and the weak current is input to the base of the NPN transistor 29.

On the other hand, a compensation current of 24V (B
voltage) is compensated, and this is input to the delay relay 24 from the emitter side of the transistor 29, turning on the primary side switch.

This causes the secondary side output, to which a constant current is always applied from the output, to conduct through the delay element, and generates a signal that activates the driving solenoid of the moving knife 14 with a slight delay of a certain period of time, and this signal causes the voltage to increase. approximately OV, and the moving knife 14 is moved forward by the potential difference.

In addition, in the figure, 31 and 33 are light emitting diodes, and 32
is transistor 29 and delay relay 24
A protective capacitor 34 represents a resistor for limiting overcurrent.

Further, the delay relay 24 is provided with a volume for adjusting the delay element, so that the delay time can be adjusted as appropriate.

As the moving knife 14 moves forward, the through hole 12
Shear the wire-like legs of the parts inserted inside,
Further, the moving knife 14 continues to move forward, bending the legs of the cut parts in a certain direction and clinching them. After the moving knife 14 has completely stopped operating, it is automatically returned to its original position under computer control, and at the same time, the clinch cutter portion and head are also returned to complete one process.

Since the present invention has the above-mentioned configuration, there is no need to use a limit switch etc. to delay the operation of the moving knife, so there is no need to stop work to replace worn out parts, and the work is significantly reduced. In particular, the delay relay with a built-in delay element has a volume that can adjust the delay time appropriately, so the delay time can be adjusted arbitrarily depending on the length of the component leg to be attached. It is possible to further improve work efficiency.

Furthermore, even if the fixed knife wears out over time, the fixed knife will remain at the same distance in the radial direction from the center of the polygonal or circular fixed knife and be rotationally symmetrical to each other. Since there are multiple through-holes in which the long holes for inserting the component legs and the holes for the mounting screws are connected, the long holes for inserting the component legs are formed in the form of long grooves by repeated shearing of the legs of the component. When the opening edge of the fixed knife 12b is worn out, simply change the mounting position (angle) of this fixed knife and use another elongated hole 12b for inserting the component leg to move the moving knife 14 forward and backward. It can be used immediately by simply aligning and reinstalling it, and if all the through holes on one side become unusable, the fixed knife can be reversed and the through hole openings on the opposite side can be re-opened. It is efficient because it can be installed and used after aligning the parts in sequence, and it is also possible to clinch the legs of the parts at the same time as cutting, which not only makes the installation of the parts even stronger, but also eliminates the need for expensive fixing devices. As a result of eliminating the need to prepare a large number of knives, various beneficial effects can be achieved, such as being able to significantly reduce the cost of the product.

In the above embodiment, the shape of the fixed knife was described as being approximately triangular in plane, but the shape is not necessarily limited to this, and it may be square or more polygonal, or circular. Moreover, it is also effective to provide a plurality of through holes radially at the tip of each polygon or at a position near the circumference of the circle, which serve both as holes for inserting the component legs and as holes for mounting screws.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of the clinch cutter portion according to the present invention. FIG. 2 is a perspective view of the blade for the clinch cutter. Figure 3 is an enlarged side view of the main part of the tip of the moving knife. FIG. 4 is a moving knife operation circuit diagram. 1...Housing, 4...Lid, 5...Piston rod, 7...Piston, 10...Fixing base, 1
DESCRIPTION OF SYMBOLS 1...Fixed knife, 14...Moving knife, 19...Press member, 22, 23...Air hose, 24...Delay relay, 26...Solenoid for advancing the clinch cutter section.

Claims (1)

[Scope of utility model registration request] A head part that descends to insert the wire-like legs of the component from above into the printed wiring board, and a clinch cutter part that approaches the lower side of the printed wiring board in synchronization with the descent of the head part. and,
A fixed fixed knife for shearing the wire-like leg attached to the clinch cutter part to a predetermined length on the back surface of the substrate, and a moving knife that slides along the fixed knife. A delay relay having a built-in delay element with a volume that can appropriately adjust the delay time between the actuation signal generating section of the head section and clinch cutter section and the solenoid input section for driving the moving knife. In addition to intervening,
The fixed knife has a polygonal shape of at least a triangular plane or a circular shape, and is installed at one end of the elongated hole for inserting the component leg at a position equidistant in the radial direction from the center and rotationally symmetrical to each other. A clinch cutter mechanism characterized by having a plurality of through holes in which holes for mounting screws are connected.