JP2005511322A - Cordless soldering iron - Google Patents

Abstract

  The soldering iron comprises a graphite tip having two separate pieces (9, 10) that are electrically separated from each other. When the two pieces at the tip are applied to an electrically conductive material such as the material to be soldered, an electrical circuit between the tip pieces (9, 10) and the power source (8) is completed. Thus, the tip can reach operating temperature in a short time. When the tip is moved away from the bond, the electrical circuit is broken and the tip material is quickly cooled to a safe temperature. Advanced materials allow higher power output than other battery powered portable soldering irons.

Description

(Cross-reference to related applications)
This application is a continuation-in-part of US patent application Ser. No. 09 / 726,546 (filed Aug. 18, 2000) and US provisional application No. 60 / 149,416 (filed Aug. 18, 1999). ) Claim priority.

  The present invention relates to a cordless electrical device, and more particularly to a soldering iron and a soldering iron tip.

  For many industrial and hobbyists, it is necessary to manually create conductive connections between various electrical components. To create such a connection, a great variety of soldering irons have been developed for use in a variety of applications. Its applications include printed circuit board repair, use in the telecommunications industry, and use in heavy industry electrical and electromechanical equipment production and repair. Existing soldering irons vary depending on power source, application, performance, shape, size, temperature, tip type, heat source, price, and portability.

  Regardless of the size or ability of the soldering iron, existing soldering iron tips generally fall into two main types. One consists of a heating element surrounded by a nonconductive film material and then covered by a thermally conductive metal shell. This tip is heated by passing electricity through a heating element. The tip size varies greatly depending on the application. The power source can also be from a 2.4 volt battery to a conventional outlet at 220 volts AC. Regardless of the power source, the current to the heating element is usually controlled by a switch in the electrical circuit leading to the heating element. The switch is often a manual switch placed on the outer case of the soldering iron.

  Another soldering iron tip includes a solid tip of a thermally conductive material (usually metal). Such a solid tip is heated by burning butane. Such soldering irons are usually portable and butane is supplied from a cartridge in the instrument.

  There are many problems with current types of soldering irons. Soldering irons that must be plugged into conventional electrical outlets lack mobility and are limited in use. Regardless of the tip type, the time generally required to initially reach the soldering temperature is in the range of 10-60 seconds. If the soldering iron is not completely cooled between uses, the next use may not require that much start-up time, but it is still not ready for use. Similarly, because the time required for the desired cooling can be long, there is a risk of burning the user and their surroundings after the tool is removed from the processing surface and before the tool is cooled. Furthermore, since the metal tip can be soldered to the connection, the connection can be damaged when the tip is released and further repairs may be required.

  Existing cordless soldering irons solve the problem of mobility of soldering irons connected to conventional outlets, but at the expense of additional problems. Butane irons require the user to store and maintain highly flammable gases and do not solve the other drawbacks described above. Existing battery-powered cordless soldering irons can typically produce only 125 connections per full charge and can only correspond to power outputs in the range of about 15-25 watts.

  To ensure that the user can fully see that the joint has been soldered, existing electric soldering irons have a small lamp on the soldering iron to illuminate the tips and connections. Sometimes. In these devices, the light is controlled by the same switch that controls the current to the heating element. The disadvantage of this system is that light cannot be used without using the tip of a soldering iron. Therefore, if the user wants to illuminate the surroundings without soldering or heating, the user needs to carry another flashlight.

  As noted above, soldering irons are primarily used to create electrically conductive connections in various portable electrical and electronic equipment. Visual inspection of the soldered connection cannot always accurately determine whether the connection is correctly formed and is currently electrically conductive. Thus, a user who wants to test the connection or electrical continuity between any two separate points in the circuit must carry a separate continuity tester.

  Thus, there is a need for a soldering iron that can be heated and cooled in a short time to minimize the risk of burning the user and their surroundings. Ideally, the soldering iron is portable and can be used to make many connections with high power output without recharging. In addition, there is a need for a portable soldering iron that can be used as a flashlight and / or continuity tester to reduce the number of instruments that a user carries to the work site.

  Generally described, the present invention provides a soldering iron having a graphite tip having two separate pieces that are electrically isolated from each other. Each tip crack is electrically connected to both sides of the power supply. When the cracks at the tip are applied to an electrically conductive material such as a material to be soldered, an electrical circuit between the crack at the tip and the power source is completed. The crack at the tip is made of a material having high electrical resistance and low thermal conductivity. Thus, the tip can reach operating temperature in a short time. When the tip is moved away from the joint, the electrical circuit is interrupted and the tip material is cooled in a short time.

  A separate switch is not required because electricity can only flow when the two parts of the tip are electrically connected. Furthermore, the soldering iron can be used without waiting for its tip to be heated. The tip is also heated and cooled in a short time, reducing the risk of burning the user and / or its surroundings. Furthermore, the tip material eliminates the risk of the tip sticking to the joint. The advanced material also enables higher power output than other known battery powered portable soldering irons and allows for over 300 bonds per full charge.

  According to a further aspect of the invention, in one embodiment, the soldering iron also includes a light disposed on the case to illuminate the tips and connections. The light is controlled by a separate switch and allows the instrument to be used to illuminate the user's surroundings without actually heating the tip. According to this aspect of the invention, it is possible to avoid the need for the user to carry a separate light source when working or trying to work in a place where there is not enough light. .

  According to another aspect of the present invention, embodiments are provided in which the instrument also includes an electrical lead connected in series with a lamp, a power source, and a continuity test probe. According to this aspect of the invention, the soldering iron can be tested for circuit continuity by direct application of the leads and probe to the newly soldered connection or another part of the circuit to be tested. According to this aspect of the present invention, it is possible to avoid the need for the user to carry a separate continuity tester to perform this function.

  Many of the above aspects and attendant advantages of the present invention may be more readily understood as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings.

  FIG. 1 illustrates one embodiment of a cordless soldering iron formed in accordance with the present invention. The soldering iron 1 controls the electric light 4 and the electric light 4 arranged on the body 3 to illuminate the tip 2 attached to the body 3, the tip 2 and the surrounding processing surface (not shown). It includes a switch 5 disposed on the body 3, a continuity test lead 6 and a continuity test probe 7 disposed on the body 3, and power means 8 (see FIG. 5).

  More particularly, the body 3 includes an elongated, substantially tubular member of rigid heat resistant material (such as plastic or a material known to those skilled in the art). The body is a single structure assembled from parts and configured to maintain sub-components as follows. Those skilled in the art will recognize that the configuration of the body can vary greatly for use in different applications.

  With reference to FIGS. 2, 3 and 4, the tip 2 includes two electrodes 9 and 10. The electrodes 9 and 10 are electrically separated from each other by an insulator 11 disposed therebetween. In the embodiment illustrated in FIGS. 2, 3 and 4, the electrodes 9 and 10 are semi-cylindrical in cross section. In the longitudinal direction, each electrode taps into a conical shape at an angle A along the distal third and is further cut off at an angle B at the distal tip to apply to the joint to be soldered To form a flat, angled surface. One skilled in the art will recognize that the tip size and shape can also vary greatly for use in different soldering applications.

  The electrodes 9 and 10 are preferably formed of graphite or a material containing graphite. For example, a battery electrode comprising graphite (battery electrode obtained from Everedy (R) Super Heavy Duty Battery Model No. 1209 manufactured by Everevery Battery Company, Inc. (Cleveland, Ohio) provides acceptable results). did. Alternatively, the electrodes can be formed from other materials (eg, germanium or silicon) that are electrically semiconductive and have a low thermal conductivity. The electrical resistivity of the tip material is preferably greater than 1,500 micro-ohm cm and 3,000 micro-ohm cm. On the other hand, the thermal conductivity is preferably less than 10 BTU / hr-ft- ° F. and preferably in the range of 1-10 BTU / hr-ft- ° F. Upon application of electricity, the electrode material reaches a temperature of about 600 ° F. within a few seconds and remains solid at a temperature greater than about 1,000 ° F. Furthermore, the electrode material is sufficiently compressed and applied so that the electrode is manufactured to a tolerance of less than about 1 mm and is held firmly in place by the body 3 and applied to the connection to be soldered without mechanical interference. It preferably has a tensile strength. The tip should have a density in the range of 1.5 to 1.75 g / cc and a minimum bending strength of 1,500 psi.

  In one embodiment, the insulator 11 is formed from mica. Alternatively, the insulator 11 can be formed from a solid dielectric material that can withstand temperatures in excess of about 1,000 ° F. without changing state.

  The tip 2 is attached to the body 3 in any conventional manner (preferably removable). Those skilled in the art will recognize that the means for attaching and removing the tip to the body can vary greatly for use in different soldering applications. Also, by making the tip removable, it is possible to use different tips for different applications using the same instrument. When fixed, the electrodes 9 and 10 are separately electrically connected to the positive and negative terminals of the power means 8 in a conventional manner. Various power means 8 are used (e.g. rechargeable or non-rechargeable batteries, or low voltage provided via a transformer from line voltage). The power means shown in FIG. 1 is a pair of nickel cadmium batteries housed within the body 3 to provide a nominal voltage of 2.4 volts and 700-750 milliamp hours. The electrodes 9 and 10 can be electrically separated from the power means 8 by a switch or other means for interrupting current in the electrical circuit, if desired.

  When both electrodes 9 and 10 are applied to an electrically conductive or semiconductive material (such as solder), they pass through the electrode 9 from the positive terminal of the power means 8 and through the electrically conductive or semiconductive material that is tipped. Through the electrode 10 and back to the negative terminal of the power means 8 to complete the electrical circuit. The current heats electrodes 9 and 10 to a temperature above about 600 ° F. within seconds, allowing the instrument to be used thereafter in a manner similar to a conventional soldering iron. When configured in this way, the device provides an alternating current equivalent to about 25-50 watts to the joint to be soldered. A further property of the preferred material for the electrode is that it cannot be soldered to the joint during use. If the user of the device wishes to stop applying heat, the device is separated from the electrically conductive or semiconductive material and blocks the current. When electricity is interrupted, the electrode cools to a temperature that is safe for contact with human skin or clothing within seconds.

  The device optionally includes a conventional electric light 4 (eg, an incandescent bulb or a light emitting diode). As shown in FIG. 1, the light 4 is arranged on the body 3 so that the emitted light illuminates the tip 2 and the surrounding processing area during use. As shown in FIG. 5, the light 4 is electrically connected to the power means 8 and controlled by the switch 5 in the conventional manner. When the switch 5 is closed, the circuit is completed from one terminal of the power means 8 through the switch 5, through the electric light 4 and back to the other terminal of the power means 8 without applying electricity to the tip 2. Illuminate the electric light 4. Since the electric light 4 can be switched on without heating the tip 2, the light can be used to illuminate the user's surroundings without the risk of accidentally burning the user or nearby flammable material.

  As shown in FIG. 1, the apparatus is optionally provided with a continuity test assembly having a continuity test lead 6 and a continuity test probe 7. Conductor 6 further includes a wire 12 (eg, a 26 gauge wire). The wire 12 extends from the body 3 at one end, and an alligator clip 13 is attached at the distal end of the wire 12. The continuity test probe 7 is a probe similar to that used in a conventional electrical test facility, and is, for example, a needle-shaped probe having a short rigid electrical conductivity. Those skilled in the art will readily appreciate that the continuity test leads and continuity test probes can be constructed from any electrically conductive material without departing from the spirit and concept of the present invention. As shown in FIG. 5, the continuity test lead 6 is electrically connected to the power means 8 through a path extending through the electric light 4. The probe 7 is connected to the opposite terminal of the power means 8. Referring to FIG. 5, the tip is connected to power means 8 in series. A path 20 is provided parallel to the tip. The light 4 and the switch 5 are installed in series along the path 20. The lead 6 is connected to the path 20 at a contact 22 located between the light 4 and the switch 5. The assembly is used to test the circuit by fastening the alligator clip 13 to one side of the circuit to be tested and bringing the probe 7 into contact with the other side of the circuit. If the circuit under test is electrically continuous, current is passed from the power means 8 through the electrical light 4, through the continuity test lead 6, through the circuit under test, through the continuity test probe 7, and power. Returning to means 8, the circuit is thus completed and the electric light 4 is illuminated. The illumination of the light 4 demonstrates the continuity of the circuit under test in a short time. This embodiment is particularly useful for cordless soldering irons because the user can test the soldered joint without having to obtain or carry a separate instrument.

  As shown in FIG. 1, end caps 14 and 15 can be used to protect tip 2 and continuity test lead 6 from damage. The end cap is removably secured to the body 2 by conventional means (eg, friction fit, clamp, threaded surface, etc.).

  While preferred embodiments of the invention have been illustrated and described, it will be appreciated that various changes can be made without departing from the spirit and concept of the invention.

  The embodiments of the invention in which an exclusive property or right is claimed are defined in the claims.

1 is an elevational view of one embodiment of a soldering iron formed in accordance with the present invention. 1 is a front view of one embodiment of a soldering tip formed in accordance with the present invention. FIG. FIG. 3 is a side view of the soldering tip shown in FIG. 2. FIG. 3 is an end view of the soldering tip shown in FIG. 2. FIG. 2 is a circuit diagram of use of the embodiment of FIG.

Claims (18)

A tip assembly for a soldering iron powered by power means, the assembly comprising two electrodes, each electrode having an electrical resistivity greater than 1,500 micro-ohm cm, each electrode being A tip assembly electrically isolated from the other by an insulator disposed between the electrodes, each of the electrodes configured to be separately electrically connected to the positive and negative terminals of the power means . 2. The electrode of claim 1, wherein each of the electrodes has a thermal conductivity of 10 BTU / hr-ft- ° F. or less, a flexural strength of about 1,500 psi or more, and a density of about 1.5 to 1.75 g / cc. Tip assembly. The tip assembly of claim 2, wherein each of the electrodes has a thermal conductivity of 1 to 10 BTU / hr-ft- ° F. The tip assembly of claim 1, wherein each of the electrodes has an electrical resistivity greater than 3,000 micro-ohm cm. 5. The electrode of claim 4, wherein each of the electrodes has a thermal conductivity of 10 BTU / hr-ft- ° F. or less, a flexural strength of about 1,500 psi or more, and a density of about 1.5 to 1.75 g / cc. Tip assembly. 6. The tip assembly of claim 5, wherein each of the electrodes has a thermal conductivity of 1-10 BTU / hr-ft- ° F. Improvements in soldering irons powered by power means
A soldering tip comprising two electrodes, each electrode having an electrical resistivity of 1,500 micro-ohm cm or more, each electrode being electrically connected from the other by an insulator disposed between the electrodes And each of the electrodes has a soldering tip configured to be separately electrically connected to the positive and negative terminals of the power means. 8. The electrodes of claim 7, wherein each of the electrodes has a thermal conductivity of 10 BTU / hr-ft- ° F or less, a flexural strength of about 1,500 psi or more, and a density of about 1.5 to 1.75 g / cc. Tip assembly. 9. The tip assembly of claim 8, wherein each of the electrodes has a thermal conductivity of 1-10 BTU / hr-ft- ° F. The tip assembly of claim 7, wherein each of the electrodes has an electrical resistivity greater than 3,000 micro-ohm cm. 11. The electrodes of claim 10, wherein each of the electrodes has a thermal conductivity of 10 BTU / hr-ft- ° F or less, a flexural strength of about 1,500 psi or more, and a density of about 1.5 to 1.75 g / cc. Tip assembly. The tip assembly of claim 11, wherein each of the electrodes has a thermal conductivity of 1-10 BTU / hr-ft- ° F. A soldering device comprising a tip attached to a body and power means, the tip being held firmly in place on the body and comprising two electrodes, each electrode being 1,500 micro-ohm cm Each electrode is electrically separated from the other by an insulator disposed between the electrodes, each of the electrodes being electrically connected to the positive and negative terminals of the power means separately. And a body comprising an elongate, substantially tubular member comprised of any rigid refractory material. 14. The electrodes of claim 13, wherein each of the electrodes has a thermal conductivity of 10 BTU / hr-ft- ° F or less, a flexural strength of about 1,500 psi or more, and a density of about 1.5 to 1.75 g / cc. Tip assembly. The tip assembly of claim 14, wherein each of the electrodes has a thermal conductivity of 1-10 BTU / hr-ft- ° F. The tip assembly of claim 13, wherein each of the electrodes has an electrical resistivity greater than 3,000 micro-ohm cm. 17. The electrodes of claim 16, wherein each of the electrodes has a thermal conductivity of 10 BTU / hr-ft- ° F or less, a bending strength of about 1,500 psi or more, and a density of about 1.5 to 1.75 g / cc. Tip assembly. The tip assembly of claim 17, wherein each of the electrodes has a thermal conductivity of 1-10 BTU / hr-ft- ° F.

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