JP4636615B2 - Multi-point heater chip - Google Patents

Description

The present invention relates to an apparatus used for heat caulking a resin member, and more particularly to a structure of a multi-point heater chip for simultaneously heating and pressing a plurality of locations.

Conventionally, for fixing between resin members or a resin member and a member made of a different material, one resin member is provided with a protrusion, and a hole is provided at a position corresponding to the protrusion of the other member. So-called heat caulking is widely performed in which heat and a pressing force are applied to the tip of the protrusion protruding after penetrating the wire and the two members are fixed so as to crush the vicinity of the softened tip.

In this operation, heat generated by electric resistance has been widely used to apply heat to the bonded portion. When it is applied to small-scale production, the tip of the soldering iron is processed appropriately, for example, to crimp the protrusions made of resin one by one. To increase efficiency, multiple protrusions can be applied at once. Ingenuity has been made. In recent years, a pulse heat power source has been used to obtain resistance heat generation for the purpose of improving the quality and efficiency of the caulking work.

Here, the pulse heat power supply is a power supply that provides a rapid temperature rise of the heater chip by instantaneously supplying a large current to the heater chip that is in direct contact with the resin during heat caulking, and performing more accurate temperature control. It is distinguished from a power source used in a so-called constant heat system that stably heats using a working portion having a relatively large heat capacity.

In addition, the constant caulking type heat caulking has been mainly applied to the above-described tool for remodeling the solder iron and the apparatus for caulking a plurality of protrusions at a time. That is, when caulking a plurality of protrusions at once, it is common to heat a block having a large heat capacity with a heater and to heat the plurality of protrusions provided in communication with the block by heat conduction. . In the case of such a constant heat method, the object to be bonded is only heated to the softening temperature or higher, and it is impossible to control the temperature so as to raise or lower the heating temperature during one heat caulking step.

Under such circumstances, an attempt has been made to realize a device for simultaneously caulking a plurality of protrusions in a thermal caulking device that heats a heater chip having a small heat capacity in a short time as in Patent Document 1, A technology is disclosed in which a heater chip and a pair of energization blocks for supplying current to the heater chip are regarded as a group, and a plurality of the groups are bundled together to connect power lines to a plurality of pairs of energization blocks to supply power. Yes.

However, in this method, in order to fix small parts, there is a structural limit in heat caulking the protrusions formed at a narrow pitch, and a plurality of the masses including the power supply block are required. Since wiring and a distribution device for supplying a large current corresponding to the power supply block are necessary, the entire device becomes expensive. In view of this situation, the applicant has provided a plurality of protrusions on a single heater chip in the heat caulking of the pulse heat method.

FIG. 5 shows a chip having a plurality of protrusions, which is drawn in a perspective view from the side where the tip of the protrusion can be seen. In FIG. 5, reference numeral 81 denotes a heater chip, which is made of a plate-like metal member bent in a substantially U-shape. Reference numerals 81a and 81b denote fixed ends positioned at both ends of the plate-like heater chip. By fixing these fixed ends to a pair of electrodes (not shown), a current flows through the entire heater chip 81.

Reference numerals 82, 83, 84, and 85 denote protrusions, and their working surfaces, which are the tips, come into contact with the protrusions of the object to be joined and are pressed while being heated. Here, the working surface of these protrusions is formed with a dome-shaped recess so as to easily press the protrusion of the object to be joined. Further, these protrusions are erected by cutting integrally with the plate-shaped heater chip main body, so that they are square columns that can be easily cut. However, these may be other polygonal columns or cylinders.

Japanese Patent Laid-Open No. 9-23496 (page 4, FIGS. 11 and 13)

However, when a heat caulking operation is performed using such a heater chip, the current from the pulse heat power source flows almost only in the plate-shaped body, and the protrusions 82, 83, 8
Nos. 4 and 85 are merely raised in temperature by heat conduction from the heated plate-like main body. Therefore, there is a time difference in temperature change between the plate-shaped main body and the tip of each protrusion, and the merits of the pulse heat method that realizes instantaneous temperature rise and temperature control cannot be fully utilized. In addition, due to the structure of the object to be bonded, when the amount of heat flowing out to the object to be bonded during heating is not uniform in each protrusion, it is not possible to perform suitable temperature management for the protrusions of all the objects to be bonded.

In order to solve such a problem, the present invention makes it possible to heat staking a plurality of protrusions of an object to be bonded simultaneously, and to perform a uniform and high-quality heat staking operation on the plurality of protrusions.

As the present invention is the first aspect, with the resistance heating by passing a current through the intermediate portion from one end to the other, and heating the plurality of projections provided on the intermediate portion by the heating, the plurality of projections A multi-point heater chip that heats the work surface at the tip of the joint by simultaneously contacting the work piece to be joined,
The intermediate portion is constituted by a plate-like portion formed in a plate shape and the plurality of protrusions formed on one surface of the plate-like portion, and a recess corresponding to each of the protrusions from the other surface side of the plate-like portion. Forming a place,
This recess, and wherein the diverting plate thickness portion content of the plate-like portion and between empty, the current flowing through the intermediate portion to the plate portion and the protrusion in part of a region directly under at least the projections Multi-point heater chip to do. Is to provide.

Further, as a second aspect of the present invention, the recess is a slit-like recess formed in a direction crossing the current flowing from the one end to the other end and including a region immediately below the corresponding protrusion. Except for the region directly under the protrusion, the plate-like portion is a slit penetrating in the plate thickness direction, and the amount of current flowing through the plate-like portion and the amount of current flowing through the protrusion can be adjusted by the length of the slit. The multipoint heater chip described as the first aspect is provided.

Further, according to a third aspect of the present invention, the recesses reach the vicinity of the action surface of the corresponding protrusions, so that the gate-shaped protrusions straddle the slit-like recesses in the direction of the current. there is provided a multi-point heater chip according to Rukoto forming forms a second aspect, characterized.

According to a first aspect of the present invention, current flowing between portions in the heater chip, blocked by the space of the root portion of the projection erected on the plate-like portion, a portion of the current to bypass the space For this reason, since the protrusion flows, resistance heat generation of the protrusion itself occurs. That is, by controlling the output of the pulse heat power source, it becomes possible to control the resistance heat generation of the protrusion itself, which contributes to the improvement of the quality of heat caulking. Also, in order to perform heat caulking at a plurality of locations at the same time, it is only necessary to replace the heater chip with one for caulking, thereby reducing the cost of the apparatus.

According to the second aspect of the present invention, the space formed in the plate-like portion of the heater chip is formed into a slit shape in the direction crossing the current, and the length of the slit-like space is adjusted to obtain a plate shape. since part of the current is also Ru can intercept part extends adjustment range of the current flowing more said projections.

According to the third aspect of the present invention, since the cross-sectional area of the flow path of the current flowing through the protrusion formed on the plate-like portion of the heater chip can be reduced, the adjustment range of the amount of current flowing through the protrusion is widened. more temperature control during thermal caulking is allow precise.

Next, an embodiment of a multipoint heater chip according to the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a side view showing a main part of a thermocompression bonding apparatus according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a heater chip, which is made of a plate-like metal bent in a substantially U shape, and both ends thereof are fixed to a pair of power supply blocks 2a and 2b. The pair of power supply blocks 2a and 2b are fixed to the insulating block 3 in a state where they are insulated from each other, and the insulating block 3 is fixed to a rod 4, which is driven by a command from a control unit (not shown). It moves up and down by the drive means 5.

Further, one end of power supply cables 6 a and 6 b is connected to the pair of power supply blocks 2 a and 2 b, and the other end is connected to output terminals 7 a and 7 b of the pulse heat power source 7. Further, a thermocouple 8 is fixed to the upper surface of the middle part of the heater chip 1, and the lead 8 of the thermocouple 8 is fixed.
a is connected to the terminal 7 c of the pulse heat power source 7. On the other hand, a tube 11 passing through the rod 4 and the insulating block 3 and having a nozzle 11a at one end directed to the heater chip 1 is provided, and the other end of the tube 11 is connected to an air supply means (not shown).

A member to be joined is disposed below the heater chip 1. In this example, two resin members 9 and 10 are placed on a stage (not shown). One member 9 has a plurality of protrusions 9a, and the other member 10 has a plurality of holes 10a.
It is the state penetrated by a. For example, such an assembly form can be seen when a camera lens assembly is fixed to the inner surface side of a resin case of a camera-equipped mobile phone.
May be not only resin but also all or part of it may be metal, and the amount of heat flowing out when the heater chip 1 contacts the member to be joined may not be uniform at each protrusion.

When an output command is issued to the power source 7 here. Energization is performed to the pair of power feeding blocks 2a and 2b. Due to this energization, a large current flows from one end of the heater chip 1 to the other end, and the temperature of the heater chip 1 rapidly increases due to resistance heat generation. At this time, since the thermocouple 8 fixed to the heater chip 1 returns the temperature information to the pulse heat power source 7, the pulse heat power source 7 is connected to the heater chip 1.
The output current is feedback controlled based on the temperature. Further, the pulse heat power source 7 stores a preset temperature profile so that the temperature of the heater tool 1 is raised or lowered to an optimum temperature with time in a single joining process, and feedback based on this profile is performed. Take control. Further, in order to quickly lower the temperature, the ejection of air from the nozzle 11a to the heater chip 1 is used.

Next, the current flow of the energized heater chip will be described with reference to FIG. FIG. 2 shows a heater chip according to the first embodiment of the present invention. In FIG. 2A is a drawing of the heater chip 101 as viewed from the direction of the object to be joined, and FIG. 2B is a cross-sectional view taken along the plane XX shown in FIG. 2A. is there. In FIG. 2, 101a is one end of the heater tool 101, and 101b is the other end, both of which are connected to a pair of power supply blocks and energized. In the case of the present invention, it does not matter whether the current is forward or reverse by energization, whether it is direct current or alternating current, and whether it is pulsed.

Here, it is assumed that a current flows from one end 101a to the other end 101b at this moment, and the flow is schematically indicated by an arrow A. The current flows through the middle part 10 of the heater chip 101.
1c. In this plate-like intermediate portion 101c, in FIG.
In (b), spaces (recesses) are formed at positions indicated by reference numerals 31 and 32. For this reason, the electric current which bypasses this flows in a processus | protrusion.

Next, the second aspect of the present invention will be described with reference to FIG. FIG. 3 shows the heater chip according to the second embodiment of the present invention as viewed from the direction of the object to be joined. Again, the flow of current is schematically indicated by arrows a. In this embodiment, the space is made into slits 41, 42, 43, 44 in a direction crossing the current, the slit 42 is shorter than the slits 41, 44, and the slit 43 is longer than the slits 41, 44.
Note that, in the region other than the standing portion of each protrusion (just below the protrusion), these slits penetrate the intermediate portion 102c in the plate thickness direction.

Therefore, by changing the length of the slits in the areas other than the standing part of each protrusion (directly under the protrusion), the partial cross-sectional area of the plate-like part is adjusted, and the amount of current flowing through the protrusion can be adjusted. Can do.

Next, a third aspect of the present invention will be described with reference to FIG. FIG. 4 shows a heater chip according to the third embodiment of the present invention, and this heater chip is denoted by reference numeral 103. Again, the current flow is indicated by arrows c. 4A is a drawing of the heater chip as seen from the direction of the object to be joined, and FIG. 4B is a cross-sectional view taken along the plane Y-Y shown in FIG. 4A. is there.

Here, in the areas other than the standing portions of the protrusions (directly below the protrusions), the slits are equivalent to the second aspect described above, but as shown in FIG. In this case, the slit extends deeply in the direction of the tip of the protrusion to form a space near the working surface, and the protrusion formed into a gate shape by this space is in a state of straddling the slit in the direction in which the current flows. Yes. Therefore, the cross-sectional area of the current flow path of these protrusions can be changed, and the temperature range to be controlled is expanded. Also, a temperature change that is sensitive to changes in current can be obtained.

Although the embodiment of the present invention has been described above, the protrusion formed on the heater chip is not limited to a quadrangular prism, and may be another polygonal column, a cylinder, or an elliptical column, and the shape of the entire protrusion is a polygonal pyramid or a cone. However, it may be a combination thereof. Moreover, although the front-end | tip of protrusion is drawn on the plane in the figure, what is necessary is just to process into a shape suitable for each heat crimping. Furthermore, the number of the plurality of protrusions is not limited to four, and two
It goes without saying that the same effect can be obtained even if any number of the number is applied.

The principal part side view which shows embodiment of this invention Detailed view of the heater chip showing the first aspect of the present invention Detailed view of heater chip showing the second aspect of the present invention Detailed view of heater chip showing the third aspect of the present invention Perspective view showing conventional technology

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, 81, 101, 102, 103 Heater chip 2a, 2b Feeding block 3 Insulating block 4 Rod 5 Driving means 6a, 6b Feeding cable 7 Pulse heat power supply 8 Thermocouple 9, 10 Joined 21-24, 51-54, 82-85 protrusion

Claims (2)

Resistive heat is obtained by passing an electric current from one end to the other end through the intermediate portion, and the plurality of protrusions provided on the intermediate portion are heated by this heat generation, and the working surfaces at the tips of the plurality of protrusions are joined. It is a multi-point heater chip that heats by touching an object at the same time,
The intermediate portion is constituted by a plate-like portion formed in a plate shape and the plurality of protrusions formed on one surface of the plate-like portion, and a recess corresponding to each of the protrusions from the other surface side of the plate-like portion. Forming a place,
By this recess, the plate thickness portion of the plate-like portion is made a space in at least a part of the region immediately below the protrusion, and the current flowing through the intermediate portion is divided into the protrusion and the plate-like portion. Heater chip. The recess is formed in a direction crossing the current flowing from the one end to the other end, and is a slit-like recess including a region immediately below the corresponding protrusion, except for the region directly below the corresponding protrusion, the plate shape 2. The multipoint according to claim 1, wherein a slit is formed through the portion in the plate thickness direction, and the amount of current flowing through the plate-like portion and the amount of current flowing through the protrusion can be adjusted by the length of the slit. Heater chip.

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