JP2010167461A - Bit of iron for lead free solder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve improvement of work efficiency at a lower cost by rapidly supplying work-heat quantity required for lead free solder. <P>SOLUTION: A bit (10) of an iron for the lead free solder is arranged at a tip of a soldering iron body (12) and is used by being mounted on a heater part (14) including a heating element (16). The bit of the iron for the lead free solder includes a cylindrical trunk part (22) into which the heater part is attachably/detachably inserted and a heat conductor (24) mounted on the tip of the trunk part. The heat conductor is tapered toward a tip like a pen nib and reduces its outer diameter, and the tip part becomes flat and is formed into a flat-blade knife shape. A notch (26) formed by surrounding the solder through approaching or contacting with it from two or more directions at the center in the flat width direction of the tip part of the heat conductor is formed. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a soldering iron tip, and more specifically, in a low-temperature soldering operation mainly using lead-free solder, the work heat amount necessary for lead-free solder is rapidly supplied to reduce the work efficiency. The present invention relates to a lead-free soldering iron tip that can be realized at a low cost.

  Soldering is a type of metal welding in which when a solder and a soldering object (hereinafter referred to as “solder etc.”) are heated to the solder melting temperature, a compound metal film is formed and bonded to the metal surface. The role of the soldering iron is to supply an amount of heat for warming the solder to the solder melting temperature.

  A conventional soldering tip is used by being attached to a heater part equipped with a heating element provided at the tip of the soldering iron body. The base (heat transfer body) that is the basic structure of the tip is a copper material. For example, it is formed in a pen tip shape.

FIG. 6 is a perspective view (FIG. 6A) of a general soldering iron currently on sale, and a side view and a sectional view of a soldering iron tip (FIG. 6B).
As shown in the figure, the soldering iron includes a soldering iron body (12) and a heater portion (14) including a columnar heating element (electric heater) provided at the tip thereof. . Here, on the outer peripheral side of the cylinder (17) forming the heater portion, a cylindrical cover pipe (18) indicated by a broken line is provided so as to cover and form a slight gap therewith.

The iron tip (30) is composed of a cylindrical stainless steel barrel (22) and a copper heat transfer body (24 ') attached to the tip of the barrel. Here, the heat transfer body (24 ′) is formed so that the tip thereof becomes tapered like a pen tip.
To attach the iron tip (30) to the heater part (14), the body (22) of the iron tip is inserted into the gap between the cylinder (17) and the cover pipe (18), and is provided at the base of the cover pipe. By rotating the cap nut (23), the iron tip is fixed to the soldering iron.

  The soldering operation is performed by first energizing the heating element of the heater section (14) to warm the heat transfer body (24 ') to an appropriate temperature, and by using this heat, the solder is heated to the solder melting temperature. Done.

  As described above, an electric heater is generally used as a heat source for supplying heat to the heat transfer body. Here, in order to warm the solder to the solder melting temperature, it is necessary to supply a predetermined amount of heat. However, if this heat supply takes a long time, a large amount of heat is wasted due to heat radiation from the tip or solder. As a result, there was a problem that work efficiency was lowered.

  By the way, in recent years, the shift from leaded solder to lead-free solder has been increasing due to regulations based on environmental issues. Lead-free solder is a solder that works at a lower temperature than lead-free solder, while lead-free solder, which is a conventional general solder, has a working temperature range of 450 to 500 degrees Celsius, while lead-free solder The working temperature range is around 350 degrees. This is because the melting point of general leaded solder itself is 180 to 230 degrees, but if you work at a high temperature (450 to 500 degrees or more), the solder melts quickly, so work at a high temperature to improve work efficiency. On the other hand, the working temperature range of lead-free solder is as low as around 350 ° C. Even if high-temperature work is performed with lead-free solder, high-temperature oxidation of the solder is remarkable and a strong oxide film is formed. Therefore, the phenomenon of soldering occurs and the work itself cannot be performed, and the degree of wear of the tip is extremely accelerated from around 380 degrees, and the production line is too expensive to enter into the mass production system. This is due to reasons such as

Therefore, in the work environment of lead-free solder, no matter how much heat is required, the output of the soldering iron cannot be raised and dealt with. Maintaining the working temperature has become a major issue.
In other words, since the working temperature of lead-free solder is low, if the soldering object is warmed by heat conduction from the heat transfer body, the temperature of the heat transfer body tends to decrease and the working temperature tends to be easily removed. However, there is a contradiction that if the output of the soldering iron is increased to deal with this, the working temperature rises too much and the working temperature of the lead-free solder is deviated, and the solution of this problem has become a major issue.

  Therefore, for example, as in “a heater for a soldering iron and a soldering iron” described in Patent Document 1, the temperature of the tip is detected by a temperature sensor such as a thermocouple, and heat is supplied from the electric heater at the same time when the working temperature is lowered. A temperature control type unit has been proposed as a lead-free solder countermeasure product. As a result, in precise soldering work, while maintaining a low working temperature, an attempt is made to ensure smooth work by instantaneously supplying heat from the electric heater during the work.

Further, the applicant of the present application is a “soldering iron tip” in Patent Document 2, and by attaching a heat storage part formed of a member having a high heat storage rate to the outer periphery of the body part of the iron tip, an expensive temperature sensor is used. Without using a temperature control unit, the temperature change of the soldering tip during soldering work is minimized, and in particular, maintenance of the low working temperature of lead-free solder is realized at low cost.
Japanese Patent Laid-Open No. 10-258358 JP 2006-315026 A

  However, temperature-controlled units using temperature sensors are expensive and often introduced to work sites, and even when a temperature-controlled tip is introduced, a certain amount of heat is required. In other operations, the speed of heat supply from the electric heater is slow, and there is a problem that workability is still poor when waiting for the heat supply from the electric heater.

  Also, with a soldering tip with a heat storage part attached to the outer periphery of the body part, the cover pipe of a general soldering iron currently sold inhibits the mounting of the tip with the heat storage part, so use it. There was a problem that I couldn't.

  The present invention was devised to solve the above-mentioned problems, and by shortening the work time of soldering work using lead-free solder by speeding up the heat supply to the solder etc., as a result, the tip and solder Reduces the amount of heat that is wasted due to heat dissipation from the heat, minimizes temperature changes at the tip of the soldering iron, maintains soldering work temperature at a low cost, and improves work efficiency. An object of the present invention is to provide a lead-free soldering tip that can be used for a conventional soldering iron.

  In order to achieve the above object, the present invention provides a lead-free soldering iron provided at the tip of a soldering iron body (12) and attached to a heater portion (14) having a heating element (16). A cylindrical body part (22) which is a tip (10) into which the heater part can be detachably inserted, and a heat transfer body (24) attached to the tip of the body part, The heat transfer body is directed to the tip like the nib, and its outer diameter is reduced, and the tip is flattened and formed into a flat sword shape, and solder is placed in the center of the flat end of the heat transfer body in the flat width direction. Provided is a lead-free soldering iron tip formed with a notch (26) which is enclosed in close proximity or in contact from two or more directions.

  Here, the planar shape of the notch (26) is approximately square, V-shaped or semicircular.

  Moreover, it is preferable that the wall thickness of the center part axial direction of the front-end | tip part of the said heat exchanger (24) is decreasing gradually toward the said notch (26).

  Furthermore, it is also preferable that the surface of the heat transfer body other than the inner peripheral surface side of the notch (26) at the tip of the heat transfer body (24) is chrome plated.

  It is also preferable that the heat transfer body (24) has a heat storage section (28) formed on the base side thereof.

  According to the present invention, by forming the heat transfer body facing the tip like the pen tip and reducing its outer diameter, the heat transfer body does not obstruct the field of view of the work place, The tip part is flattened and formed into a flat sword shape, and a plurality of directions are formed by forming a notch that encloses or touches solder from two or more directions at the center of the flat part in the flat width direction of the heat transfer body tip part. It is possible to shorten the working time by supplying heat to the solder so as to surround it and promoting its melting. As a result, it is possible to reduce the amount of heat that is wasted due to heat dissipation from the iron tip and solder, minimize the temperature change of the iron tip, maintain the soldering work temperature at a low cost, and improve the work efficiency. it can.

  Here, if the planar shape of the notch is substantially square, V-shaped or semicircular, heat can be efficiently supplied from the tip of the tip to the solder without hindering the soldering operation.

  In addition, the thickness of the heat transfer body tip portion in the flat width direction center portion axial direction is gradually reduced toward the notch, thereby facilitating the flow of molten solder to the heat transfer material tip side, It is possible to make the attachment work easier.

  Furthermore, chrome plating is applied to the heat transfer body other than the inner peripheral surface side of the notch, thereby reducing the heat dissipation from other than the inner peripheral surface side of the notch as much as possible and improving the thermal efficiency of the soldering work. The wettability of the plated portion can be lowered to prevent the solder from rising, and the chemical resistance of the tip can be increased.

  Moreover, if the heat storage part is formed on the base side of the heat transfer body, the temperature change at the tip of the iron tip can be suppressed by the rapid heat supply from the heat storage part even by the heat supply to the solder or the like. When the heat storage part is formed at the tip of the iron, it is necessary to use a soldering iron without a cover pipe.

The present invention speeds up the heat supply to the solder etc. in the soldering work using the lead-free solder which is performed at a low temperature (around 350 degrees) as compared with the leaded solder, and as a result, heat is dissipated from the iron tip and the solder. This is related to a lead-free soldering iron tip (hereinafter sometimes simply referred to as “the iron tip”) for reducing the amount of heat that is wasted.
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

First, the structure of a general soldering iron body in which the tip of the present invention is used will be described in detail with reference to FIG.
The soldering iron main body 12 includes a gripping hand portion 12a that becomes a user's handle during soldering work, a round bar heater portion 14 attached to the gripping hand so as to extend from one end of the gripping hand, and the like. The power cord 15 extends from the other end of the grip portion 12a. The grip portion 12a has a size and shape that can be easily held by wood or synthetic resin having a low thermal conductivity, for example, a round bar shape having an outer diameter of about 4 cm as shown in the figure, and a flange portion 12b is formed at one end thereof. A power cord 15 that has a shape and extends to the heater section 14 is passed through the power cord 15, and a power switch (not shown) that can be operated from the outside is provided in the path of the power cord.

  The heater part 14 shown in a perspective view in FIG. 1 accommodates a wiring 19, a thermostat 21, and a heating element 16 in a stainless steel cylinder 17 having an axial length of about 5 cm and an outer diameter of about 5 mm. Further, a cylindrical cover pipe 18 is provided on the outer peripheral side of the cylinder so as to cover and form a slight gap therewith. The heating element 16 is disposed at the tip of the heater section 14. The thermostat 21 is arranged at a position away from the heating element 16 by a predetermined distance (for example, 1 cm), and turns on / off the energization of the heating element so that the temperature of the heat transfer body described later becomes an appropriate working temperature. Further, a cap nut 23 for attaching a trowel tip of the present invention, which will be described later, in a detachable manner is secured in the vicinity of the attachment portion of the heater portion 14 to the grip portion 12a. The tip of the tip for lead-free solder, which will be described later, is inserted into the bag nut 23 by turning the cap nut 23 clockwise and tightening the cap nut 23 by loosening the cap nut 23 by rotating it counterclockwise. The portion is fixed to the heater unit 14. The iron tip is attached by inserting a part of the iron tip (body) into the gap between the cylinder 17 and the cover pipe 18 of the heater portion 14.

  Specific examples of the lead-free soldering iron tip of the present invention used by being attached to the soldering iron main body described above will be described below.

  2 (a) and 2 (b) are a plan view and a side view for showing the structure of the lead-free soldering iron tip of this embodiment, FIG. 2 (c) is an axial sectional view, and FIG. 2 (d). FIG. 4 is an enlarged view showing the state of plating at the tip of the iron tip.

  This lead-free soldering iron tip 10 is composed of a barrel portion 22 inserted into the heater portion 14 described above, and a heat transfer body 24 attached to the tip of the barrel portion, and the heater portion 14 of the soldering iron main body 12. It is a cartridge structure that is used by being attached to (see FIGS. 1 and 2).

  The body portion 22 has a thin cylindrical shape with an inner diameter of about 6 mm and an axial length of about 4 cm, and a metal having a low thermal conductivity, such as stainless steel, is used as the material thereof. The body portion 22 is inserted into the gap between the cylinder 17 of the round bar-shaped heater portion 14 and the cover pipe 18, and the end of the body portion (rear end) is inserted into the cap nut 23 at the same time as the front end of the heater portion reaches the deepest portion. It is fixed to this by rotating the cap nut clockwise.

The heat transfer body 24 includes a solid columnar base portion 53 having a thickness of about 2.5 cm (the outer diameter is less than 7 mm) whose rear end is inserted into the distal end of the cylindrical body portion 22, and this The outer shape is composed of a pen tip-shaped tip 55 having a length of about 1.5 cm formed integrally with the tip of the base.
The base portion 53 has a stepped structure in which the portion to be inserted is slightly narrowed in order to define the amount of insertion when the rear end is inserted into the body portion 22.
The tip portion 55 faces the tip like the pen tip and has a reduced outer diameter, and the tip portion is flattened and shaped like a flat blade. The leading edge 55 has a leading edge width of approximately 3 to 5 mm. The tip 55 is formed with a substantially square notch 26 at the center in the flat width direction to surround the solder in proximity or contact from three directions. The width of the notch 26 differs depending on the diameter of the solder (thread solder) used, but is about 2 mm (when the diameter of the thread solder is slightly over 1 mm). Further, the thickness of the tip of the heat transfer body 24 on the base side of the notch 26 (in the axial direction of the central portion in the flat width direction) gradually decreases toward the notch within a range of several mm.
Further, the rear surface side of the front end portion of the heat transfer body 24 stabilizes the tip of a soldering iron that is inclined and pressed against a soldering target such as a base, and expands the contact area with the base 45. It is inclined at an angle of about °.

Oxygen-free copper is used as a material for the heat transfer body 24, and iron plating is applied to the entire surface with a film thickness of 200 μm to 1500 μm as a base plating. This iron plating is intended to improve the wettability with the solder, and by ensuring a predetermined uniform film thickness, the product has a long life and good heat release.
Further, in the heat transfer body 24 that has been subjected to iron plating, the portion where the inner peripheral surface of the notch 26 at the tip is formed is a contact surface with the solder, and the surface of the iron plating layer excluding the inner peripheral surface A hard chrome plating layer and a black chrome plating layer are formed on the hard chrome plating layer (the black portion in FIG. 2D is chrome plating). This hard chrome plating is intended to increase the wear resistance and the corrosion resistance of the flux contained in the solder. The black chrome plating layer has a low wettability (high solder repellent property) and higher black chrome plating because the corrosion resistance and chemical resistance of hard chrome plating are low in the region of 350 ° C which is the working temperature of lead-free solder. Corrosion resistance and chemical resistance prevent corrosion and reliably prevent solder from rising, further ensuring the accuracy of soldering work by assuring the uniformity of the solder supply amount, and at the same time significantly reducing the wear of the tip It is for making it happen. The total thickness of the hard chrome plating layer and the black chrome plating layer is about 5 μm to 20 μm, and these chrome plating layers also have a secondary effect of suppressing wasteful heat radiation from the surface of the heat transfer body 24. is doing.

  As shown in FIG. 3 showing the use state of the iron tip 10 of this embodiment, after supplying heat to the soldering object from the iron tip lightly pressed against the soldering object such as a base, This is done by extending the thread solder to the notch 26 at the tip end of the iron tip, and supplying heat to the thread solder from three directions (right and left rear directions) to melt it.

  As described above, in the lead-free soldering iron tip of this embodiment, the solder (yarn solder) is extended to the notch formed in the iron tip and heat is supplied to the yarn solder from three directions, so that the solder can be melted quickly. As a result, the work time can be shortened, and as a result, the amount of heat that is wasted due to heat radiation from the tip or solder can be reduced to improve work efficiency.

4 (a) and 4 (b) are a plan view and a side view for illustrating the structure of the lead-free soldering iron tip of this embodiment, FIG. 4 (c) is an axial sectional view, and FIG. 4 (d). FIG. 4 is an enlarged view showing the state of plating at the tip of the iron tip.
Since the iron tip of this embodiment also has many parts common to the iron tip of the first embodiment except for the shape of the iron tip, only the parts different from the first embodiment will be described below.

The tip 55 of the heat transfer body 24 of the iron tip 10 is tapered toward the tip like a pen tip, and the tip is flattened, and the tip is flat and formed in a flat blade shape. . The leading edge 55 has a leading edge width of approximately 3 to 5 mm. The tip 55 is formed with a substantially V-shaped notch 26 that surrounds the solder in proximity to or in contact with the three directions in the center of the flat width direction. The notch 26 has a width of about 3 mm and a depth of about 1 mm (when the diameter of the thread solder is slightly over 1 mm). Furthermore, the thickness of the tip 55 of the heat transfer body 24 on the base side of the notch 26 (in the axial direction of the central portion in the flat width direction) gradually decreases toward the notch within a range of several mm, and the center of the tip portion The groove is inclined so that the axis is a valley. Chrome plating is not applied to the groove.
It is to be noted that the rear surface side of the front end portion of the heat transfer body 24 is formed so as to be inclined at an angle of about 45 °, as in the iron tip of the first embodiment.

  The use of the iron tip 10 of the present embodiment is such that after supplying heat to the soldering object from the iron tip lightly pressed against the soldering object such as the base, the thread solder is provided on the base side of the notch 26 at the tip of the iron tip. And soldering is performed by supplying heat to the thread solder from three directions (left and right lower directions) and melting it.

  In this way, in the lead-free soldering iron tip of this embodiment, the solder is rapidly melted by forming the notch of the iron tip into a V shape and supplying heat to the solder (thread solder) from three directions. In addition, by forming a groove shape that is inclined so that the central axis of the tip of the iron tip becomes a valley, the molten solder is gathered at one point at the tip center of the iron tip, and accurate soldering work is performed. It can be made easier.

5 (a) and 5 (b) are a plan view and a side view for showing the structure of the lead-free soldering iron tip of this embodiment, FIG. 5 (c) is an axial sectional view, and FIG. 5 (d). FIG. 4 is an enlarged view showing the state of plating at the tip of the iron tip.
Since the iron tip of this embodiment also has many parts common to the iron tip of the first embodiment except for the shape of the iron tip, only the parts different from the first embodiment will be described below.

The tip 55 of the heat transfer body 24 of the iron tip 10 of the present embodiment is tapered toward the tip like a pen tip, and the tip is flattened to form a flat blade. Has been. The leading edge 55 has a leading edge width of approximately 3 to 5 mm. The tip 55 is formed with a semicircular cutout 26 at the center of the flat width direction that surrounds the solder by approaching or contacting it from three directions. Further, the thickness of the tip 55 of the heat transfer body 24 on the base side of the notch 26 (the axial direction of the central portion in the flat width direction) gradually decreases toward the notch within a range of several mm, and the center of the tip It is a U-shaped groove inclined so that the axis becomes a valley. Chrome plating is not applied to the U-shaped groove and the notch inner peripheral surface.
It is to be noted that the rear surface side of the front end portion of the heat transfer body 24 is formed so as to be inclined at an angle of about 45 °, as in the iron tip of the first embodiment.

  The heat transfer body 24 has a heat storage section 28 formed on the base side thereof. The heat storage section 28 is obtained by thickening the base 53 of the heat transfer body 24 so that its diameter is about 1 cm, and increases the volume of the heat transfer body. Note that the rear end of the base portion 53 of the heat transfer body 24 is not thick because the heat storage section 28 is not formed because the heat transfer body is inserted into the body portion 22.

The use of the iron tip 10 of the present embodiment is to heat supply the soldering object from the iron tip lightly pressed against the soldering object such as a base, and then extend the thread solder to the notch 26 at the tip of the iron tip, Soldering may be performed by supplying heat to the thread solder from three directions ((left and right rear direction)) and melting it, or the thread solder is extended to the base of the notch, and three directions (left and right bottom) Soldering may be performed by supplying heat to the thread solder from the side direction and melting it.
In addition, since the heat storage section 28 is formed in the iron tip heat transfer body 24, even when heat is supplied to the solder or the like, the temperature change at the tip of the iron tip is suppressed, and the soldering operation temperature is easily maintained. ing.

  As described above, in the lead-free soldering iron tip of this embodiment, the shape of the notch of the iron tip (semi-circular shape) is devised, so that the solder can be rapidly melted and accurately as in the first and second embodiments. Thus, the soldering operation can be ensured, and the temperature change at the tip of the iron tip can be suppressed by the heat storage section.

  In the above description, the solder used is the thread solder. However, the soldering tip of the present embodiment can be used when, for example, soldering is performed by melting ball solder placed on a base or the like.

  As described above, according to the present invention, by efficiently supplying heat to the solder in the soldering work, the solder is quickly melted to shorten the work time, and as a result, heat is dissipated from the iron tip and solder. Thus, the amount of heat that is wasted can be reduced and work efficiency can be improved.

It is the perspective view which showed the soldering iron main body. It is the top view for showing the structure of the iron tip for lead free solder of Example 1, a side view, and XX sectional view. It is the figure which showed the use state of a tip. FIG. 6 is a plan view, a side view, and a cross-sectional view taken along the line XX for illustrating the structure of a lead-free soldering iron tip of Example 2. FIG. 6 is a plan view, a side view, and a cross-sectional view taken along the line XX for illustrating the structure of a lead-free soldering iron tip of Example 3. FIG. 2 is a partial sectional perspective view of a general soldering iron and a side view and a sectional view of a soldering iron tip.

10 (for lead-free solder) Iron tip 12 Soldering iron body 12a Grasping part 12b Flange part 14 Heater part 15 Power cord 16 Heating element 17 Cylinder 18 Cover pipe 19 Wiring 21 Thermostat 22 Body part 23 Cap nuts 24, 24 ' Heater 26 Notch 28 Heat storage part 53 Base part 55 Tip part

Claims (7)

A lead-free soldering iron tip (10) used at the tip of the soldering iron body (12) and attached to a heater part (14) provided with a heating element (16),
A cylindrical body part (22) in which the heater part can be detachably inserted, and a heat transfer body (24) attached to the tip of the body part,
The heat transfer body is directed to the tip like the nib, and the outer diameter thereof is reduced, and the tip portion is flattened to have a flat blade shape, and the heat transfer member tip portion is soldered in the center in the flat width direction. A lead-free soldering iron tip, characterized in that a notch (26) is formed which surrounds and comes close to or from two directions.   The iron tip for lead-free solder according to claim 1, wherein the planar shape of the notch (26) is substantially square.   The iron tip for lead-free solder according to claim 1, wherein a planar shape of the notch (26) is V-shaped.   The iron tip for lead-free solder according to claim 1, wherein the planar shape of the notch (26) is semicircular.   The lead-free according to any one of claims 1 to 4, wherein a thickness in the axial direction of the central portion of the tip of the heat transfer body (24) is gradually reduced toward the notch (26). Soldering iron tip.   The surface of the heat transfer body other than the inner peripheral surface side of the notch (26) at the tip of the heat transfer body (24) is chrome-plated. Lead-free soldering iron tip.   The lead-free soldering iron tip according to any one of claims 1 to 6, wherein a heat storage section (28) is formed on a base side of the heat transfer body (24).