JP2583149B2 - Manufacturing method of thermoelectric module - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for manufacturing a thermoelectric module for performing thermal control using the Peltier effect, and in particular, to easily and reliably determine a fine thermoelectric module lead wire. The present invention relates to a method for manufacturing a thermoelectric module that can be formed at the position of an electrode.

2. Description of the Related Art As is well known, a thermoelectric module has a structure as shown in FIG. That is, in FIG. 1, 1a and 1b are insulating substrates provided with a plurality of electrodes 2a and 2b, respectively, and between the insulating substrates 1a and 1b, both ends thereof are the electrodes 2a and 2b.
2b, a P-type thermoelectric element 3 and an N-type thermoelectric element 4 are fixed adjacent to each other.

Therefore, on the thermoelectric module, all the P-type thermoelectric elements 3
And the N-type thermoelectric element 4 are alternately connected in series by the electrodes 2a and 2b, and lead wires 5a and 5b are drawn out from both ends connected in series.

In the above structure, by supplying a current from the lead wires 5a and 5b to the P-type thermoelectric element 3 and the N-type thermoelectric element 4 connected in series, the Peltier effect causes the current to flow from the insulating substrate 1a. 1b or 1b to 1a
Then, heat is transferred according to the characteristics of the thermoelectric element corresponding to the current value.

FIG. 2 is an enlarged view of the lead wire joint in the above structure. In FIG. 2, (A) is a view of the mounting portion of the lead wire viewed from the side, and (B) is a view of the above (A) viewed from a right angle direction. In the figure, 1a and 1b are insulating substrates provided with a plurality of electrodes 2a and 2b, respectively, and between the insulating substrate substrates 1a and 1b, both ends are soldered to the electrodes 2a and 2b, Neighboring P-type thermoelectric elements 3 and N
The mold thermoelectric element 4 is fixed.

Reference numeral 2c denotes an endmost electrode in which the P-type thermoelectric element 3 and the N-type thermoelectric element 4 are connected in series. Reference numeral 5 denotes a lead wire, which is connected and fixed to the electrode 2c by solder 6. .

In the above structure, the minute thermoelectric module is manufactured, for example, by the applicant of the present invention and applied to the both end electrodes 2c, which are input / output terminals, by connecting a predetermined lead wire 5 to the input / output terminal 2c. In such cases, soldering is performed manually by using a microscope or the like.

[Problems to be Solved by the Invention] According to the above manufacturing method, each P-type thermoelectric element and N-type thermoelectric element can be fixed at the correct position with respect to each electrode of the insulating substrate. There is an object in which the distance between two opposing ceramic substrates and the width of an electrode are as narrow as 1 mm or less.

In the soldering work of the lead wire in such a minute structure, it is a difficult work using a microscope and requires a high level of skill. It is difficult to set the lead wire and supply the solder, and there is a possibility that the following problem may occur.

a, The joint between the thermoelectric element and the electrode that has already been soldered is heated to a high temperature due to heat conduction and is re-melted, adversely affecting the joint.

b. Solder scatters during soldering of lead wires to form solder balls, which short-circuits adjacent electrodes.

c) Since it is difficult to keep the amount of supplied solder constant, shortage of soldering strength occurs due to insufficient soldering strength due to an insufficient amount of solder, and a bridge between adjacent electrodes occurs due to an excessive amount of soldering.

d) In the automatic soldering using a robot and a soldering iron, the tip of the soldering iron is oxidized and becomes dirty, so that stable continuous soldering becomes difficult.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems, and a method of manufacturing a thermoelectric module by means of soldering a lead wire capable of reliably and automatically soldering a stable lead wire. It is intended to provide.

Means for Solving the Problems In order to achieve the above object, in the first invention of the method for manufacturing a thermoelectric module according to the present invention, the thermoelectric module is adjacent to each other by a plurality of electrodes respectively fixed to two opposing insulating substrates. A plurality of matching P-type thermoelectric elements and N-type thermoelectric elements are alternately connected in series, and a lead wire is soldered to electrodes at both ends connected in series, and the above-mentioned two insulating substrates are opposed to each other. In a method of manufacturing a thermoelectric module in which a P-type thermoelectric element and an N-type thermoelectric element are sandwiched and fixed, the tip of a conductive wire having a predetermined diameter is immersed in cream solder, and cream solder is attached to a predetermined length, A laser beam is radiated and heated for a predetermined time to a position above a predetermined distance from the cream solder attachment position of the conductor, and the cream solder attachment portion of the conductor is soldered to predetermined positions of the electrodes at both ends to form a lead wire. You It is characterized by that. In the second invention of the method for manufacturing a thermoelectric module, a plurality of P-type thermoelectric elements and an N-type thermoelectric element adjacent to each other are alternately connected in series by a plurality of electrodes respectively fixed to two insulating substrates facing each other. Then, a lead wire is soldered to the electrodes at both ends connected in series, and the P-type thermoelectric element and the N-type thermoelectric element are sandwiched and fixed between the two facing insulating substrates. In the method, a tip of a conductor having a predetermined diameter is immersed in cream solder to adhere the cream solder to a predetermined length, and a laser beam is irradiated at a predetermined distance from a position where the cream solder is attached to the conductor for a predetermined time. Irradiation heating, the cream solder attachment portion of the conductor is brought into contact with a predetermined position of the electrode at both ends, and the laser beam is irradiated and heated at a predetermined position in the electrode surface where the cream solder attachment portion of the conductor is brought into contact. Half Association Shi and forming a lead wire. According to a third aspect of the invention, which is mainly based on the second aspect of the method for manufacturing a thermoelectric module, a predetermined position in the electrode surface is near the cream solder attachment portion.

[Operation] According to the above-described means, since the laser wire is irradiated to the conductor immersed in the cream solder at a position distant from the cream solder attachment portion and heated, the scatter of the cream solder easily generated by the direct irradiation is performed. No solder balls are generated and the amount of cream solder that is pre-welded to the tip of the conductor is constant and has an appropriate uniform shape.The conductor with the cream solder applied to a predetermined position on the electrode is always soldered correctly. Can be attached. In addition, heat soldering is performed with a laser beam, and the vicinity of the cream solder attachment portion is heated with a laser beam, so that the element junction does not have an adverse effect due to re-melting, and adjacent electrodes are short-circuited. Is no longer to be done. In addition, since the soldering is performed by using a laser beam, the influence of oxidation and contamination of the soldering iron is eliminated.

EXAMPLES Hereinafter, details of a method of manufacturing the thermoelectric module shown in FIGS. 1 and 2 according to the present invention in the related art will be described with reference to the drawings.

FIG. 3 is a flowchart showing a manufacturing process based on the manufacturing method of the present invention, and FIG. 4 shows a thermoelectric module that has been assembled in a process before forming a lead wire based on the present invention; FIG. 5, FIG. 6, FIG. 7, and FIG. 8 are schematic views for explaining intermediate steps of the manufacturing flow shown in FIG.

In FIG. 4, reference numerals 1a and 1b denote a plurality of electrodes 2a,
A ceramic substrate (hereinafter, referred to as a ceramic substrate) provided with an insulating substrate 2b, between which both ends are soldered to the electrodes 2a, 2b. The type thermoelectric element 3 and the N type thermoelectric element 4 are fixed. Therefore, on the thermoelectric module, all P
The thermoelectric elements 3 and the N-type thermoelectric elements 4 are alternately connected in series by the electrodes 2a and 2b.

Further, 2c represents the P-type thermoelectric element connected in series and N
Electrode at the extreme end with respect to the
Are connected by means according to the present invention.

In FIG. 5, reference numeral 10 denotes a solder bath, 11 denotes cream solder in the solder bath 10, 12a, 12b, and 12c each indicate the same conductive wire 12 before being processed into a lead wire.
a, 12b, and 12c. Reference numeral 13c is cream solder attached to the tip of the conductive wire 12c.

In FIG. 6, 12c is a conductor corresponding to 12c shown in FIG. 5, 13c is cream solder attached to the tip of the conductor 12c, 14 is a laser beam emitting optical unit, and 14a is the laser beam. 3 shows a laser beam emitted from a light emitting optical unit.

In FIG. 7, 12d is a lead wire which becomes a lead wire after the laser beam is irradiated, and 13d is once melted and securely welded to the lead wire 12d because the laser beam is irradiated, Molded naturally by the weight and surface tension of the molten solder,
This shows the solder attached to the tip of the conductive wire 12d after being re-solidified by cooling.

In FIG. 8, (A) is a view from the side, and (B) is a view from above the electrode 2c except for the upper ceramic substrate. In the drawing, reference numerals 1a and 1b denote ceramic substrates provided with a plurality of electrodes 2a and 2b, respectively. Between the ceramic substrates 1a and 1b, both ends are soldered to the electrodes 2a and 2b, respectively. In total, the P-type thermoelectric element 3 and the N-type thermoelectric element 4 are fixed. Therefore, on the thermoelectric module, all the P-type thermoelectric elements 3 and the N-type thermoelectric elements 4 are alternately connected in series by the electrodes 2a and 2b, and 2c is one of the two ends connected in series. The electrodes 2c are plated with solder before soldering and fixing the P-type thermoelectric element 3 and the N-type thermoelectric element 4 adjacent to the electrodes 2a and 2b.

Reference numeral 15 denotes a laser beam emitting optical unit, and reference numeral 15a denotes a laser beam emitted from the laser beam emitting optical unit.

Reference numeral 12d denotes a conductor corresponding to the conductor 12d shown in FIG. 7, reference numeral 13d denotes solder attached to the tip of the conductor 12d, and reference numeral 16 denotes a holding mechanism for the conductor 12d.

In the flow chart of the manufacturing process shown in FIG. 3, when this processing step is started, first, as shown in FIG. 5, cream solder is put in a solder tank. The thermoelectric module before the lead wire is attached by −341377 is assembled as shown in FIG. 4 and mounted on a predetermined jig.

Next, in step 0, as shown in FIG. 5, the conductor 12 (12a) is vertically inserted into the cream solder 11 to a predetermined depth by an automated processing machine (12b), and then pulled up, and the conductor 12c is pulled up. The cream solder adheres to the tip of a predetermined length and thickness (13c).

The length and amount of the cream solder to be attached to the tip of the conductor is determined in advance by the material and dimensions of the electrodes of the thermoelectric element module, the material and diameter of the conductor, and the composition of the solder. The depth of immersion in the cream solder is determined and appropriately set in the control device of the processing machine.

Next, in step 1, as shown in FIG. 6, the conductor 12c is held vertically by the processing machine, and the laser beam emitting optical unit 14 automatically moves the conductor 12c to a predetermined position from the position 13c where the solder of the conductor 12c is attached. The upper portion is irradiated with the laser beam 14c for a predetermined time.

The irradiation position and time of the laser beam are determined in advance in accordance with the output of the laser beam emitting optical unit, the material and thickness of the conductive wire, the composition of the attached cream solder, the attached length and thickness, and the laser beam emitting optical unit 14. Set in the drive mechanism controller.

For example, good results can be obtained by irradiating a laser beam having a power of 10 watts to a portion 4 mm above the conductor tip for 4 seconds.

As shown in FIG. 7, the tip of the lead wire (12) after step 1 is attached to the tip of the lead wire 12d, the length and amount of the cream solder adhered, the adhesive force between the lead wire and the molten solder, the molten solder Solder 13d into shape determined by weight and surface tension
Is attached. After the completion of Step 1, in Step 2, the solder 13d is automatically immersed in an appropriate flux and applied in an appropriate amount.

Next, in step 3, as shown in FIG.
12d is held and fixed by the holding mechanism 16 of the automated processing machine at a predetermined position on the electrode 2c of the thermoelectric module assembled before mounting the lead wire as shown in FIG.

That is, the conductive wire 12d is brought into contact with the solder adhering portion at the center and horizontal of the electrode 2c.

In the above-described state, the laser beam 15a is applied from the laser beam emitting optical unit 15 to the solder attachment portion of the lead wire 12d in the plane of the electrode 2c.
A predetermined position deviated from 13d is irradiated and heated for a predetermined time. Therefore, the temperature of the electrode 2c and the conductor 12d rises, and the solder 13d
Is melted, and the irradiation of the laser beam is completed.
The connection with c is completed.

(Step 4) Next, in step 5, the conducting wire 12c is cut into a predetermined length to complete the entire assembling process.

In the above description, it has been described that the laser beam is applied to a predetermined position off the solder attachment portion of the lead wire in the electrode surface, but the material and shape and dimensions of the electrode, the material and thickness of the lead wire, the composition of the solder, and the laser beam Depending on the diameter of the irradiating part, appropriate positions such as a position off the tip solder attachment portion on the conductor, a position on the electrode surface that deviates from the tip solder attachment portion, or irradiation including the solder attachment portion, etc. The irradiation position and the irradiation time are set in the drive mechanism control device of the laser beam emitting optical unit 15.

For example, under predetermined conditions, good soldering can be performed with a laser output of 20 watts and an irradiation time of 3 seconds.

When the above steps are completed, the process returns to step 0 to process the next thermoelectric module.

[Effects of the Invention] As described above, according to the present invention, the conductor immersed in the cream solder bath is heated by irradiating a laser beam to a position distant from the cream solder attachment portion. The amount of cream solder that is pre-welded to the tip of the solder is constant and has an appropriate uniform shape, and the conductor with the cream solder is applied to a predetermined position on the electrode and soldered, resulting in good soldering. Can now be run. In addition, since the soldering is performed by heating with a laser beam, and the vicinity of the cream solder attachment portion is heated by the laser beam, the adverse effect due to re-melting to the element bonding portion is not caused. No short circuit. In addition, since the soldering is performed by using a laser beam, the influence of oxidation and contamination of the soldering iron is eliminated.

Therefore, it has become possible to perform tasks that required more than one minute per piece by automation in 10 seconds by automation. In addition, the quality is stable, the yield is improved, and the productivity is greatly improved. The excellent effect of being able to measure was obtained.

[Brief description of the drawings]

FIG. 1 is a diagram of a thermoelectric module. FIG. 2 is an enlarged view of a lead wire connecting portion of FIG. FIG. 3 is a process flow diagram relating to a manufacturing operation based on the present invention. FIG. 4 is a thermoelectric module diagram in which the pre-process of the process flow shown in FIG. 3 based on the present invention is completed. FIG. 5 is an explanatory view of a conductor immersed in a solder bath. FIG. 6 is an explanatory view of irradiation of a laser beam on a conductive wire. FIG. 7 is an explanatory diagram of a laser beam irradiation-completed conducting wire. FIG. 8 is an explanatory view of soldering a lead wire with a laser beam. 1a, 1b ... insulating substrate, 2a, 2b, 2c ... electrode, 3 ... P-type thermoelectric element, 4 ... N-type thermoelectric element, 5a, 5b ... lead wire, 6 ... solder, 10 ... solder Vessel, 11 ... cream solder, 12 ... lead wire, 13 ... solder, 14 ... laser beam emitting optical unit, 15 ... laser beam emitting optical unit.

Claims (3)

(57) [Claims] 1. A plurality of P-type thermoelectric elements and a plurality of N-type thermoelectric elements adjacent to each other are alternately connected in series by a plurality of electrodes respectively fixed to two insulating substrates opposed to each other, and both ends connected in series In a method of manufacturing a thermoelectric module, a lead wire is soldered to the electrodes of the portion, and the P-type thermoelectric element and the N-type thermoelectric element are sandwiched and fixed between the two facing insulating substrates. The tip of the conductive wire having the solder is immersed in cream solder to adhere the cream solder to a predetermined length, and a laser beam is radiated and heated for a predetermined time to a position above a predetermined distance from a position where the cream solder is attached to the conductive wire, thereby heating the conductive wire. A method of manufacturing a thermoelectric module, wherein a solder paste is soldered to predetermined positions of electrodes at both ends to form a lead wire. 2. A plurality of P-type thermoelectric elements and a plurality of N-type thermoelectric elements adjacent to each other are alternately connected in series by a plurality of electrodes fixed to two opposing insulating substrates, respectively. In a method of manufacturing a thermoelectric module, a lead wire is soldered to the electrodes of the portion, and the P-type thermoelectric element and the N-type thermoelectric element are sandwiched and fixed between the two facing insulating substrates. The tip of the conductive wire having the solder is immersed in cream solder to adhere the cream solder to a predetermined length, and a laser beam is radiated and heated for a predetermined time to a position above a predetermined distance from a position where the cream solder is attached to the conductive wire, thereby heating the conductive wire. The cream solder attachment portions are brought into contact with predetermined positions of the electrodes at both ends, and a predetermined position in the electrode surface where the cream solder attachment portions of the conductors are brought into contact is irradiated with a laser beam and heated to be soldered to form lead wires. To do Method for manufacturing a thermoelectric module, wherein. 3. The method for manufacturing a thermoelectric module according to claim 2, wherein the predetermined position in the electrode surface is near the cream solder attachment portion.