Abstract:
An automated soldering system with an intelligent power supply that can automatically configure the power output to interchangeable soldering cartridges, where the soldering cartridges include readable information to allow the power supply to properly power the cartridge to achieve a desired, entered operating temperature. The system includes a cartridge with an identifier that contains information particular to that cartridge, a reader able to read that information, and an indicator positioned on a connector into which the cartridge is inserted.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention: 
     The present invention relates to an automated soldering system with an intelligent power supply that can automatically configure the power output to interchangeable soldering cartridges, where the soldering cartridges include readable information to allow the power supply to properly power the cartridge to achieve a desired, entered operating temperature. In particular, the present invention encompasses the use of an identifier on the cartridges and a reader coupled to the power supply for immediate recognition of the type of soldering cartridge to be used. In addition, to inform the user that the station is operational, a LED indicator preferably located proximate to the interchangeable cartridge and activated by the automated soldering system displays various light signals for the user. 
     2. General Background and State of the Art: 
     Soldering stations have been in use for many years. The typical soldering station includes two components: a soldering iron composed of either a connector and a cartridge or a handpiece, a heater and a soldering tip, and a power supply for supplying current to the soldering iron. The cartridges have a soldering tip, which is used to solder, located at one end of the cartridge and a connector at the opposite end which can be inserted into a handle attached to a power cable extending from the power supply. The power cable may have many wires capable of carrying power and information between the power supply and the cartridge. 
     Various cartridges have different configurations for the tip. Because of the varying configurations, the tip temperature must be optimized for effective soldering. The thermal properties of the various tip configurations as well as the shape and the size of the tip will impact the optimal temperature to solder using that particular tip. Because the tips are integral within the cartridge, each cartridge becomes unique, its power requirements distinguishable only by the type of tip. Therefore. traditional soldering stations, which had only one power output level, did not optimize the functionality of the different cartridge tips available in the market. Further, cartridges with varying tip designs had to be manufactured around the parameters of a particular power supply. The second generation of soldering stations allowed the user to adjust the power output of the power supply using dials and knobs to better define the power required. These adjustable soldering stations could accommodate a far broader range of soldering tip configurations as compared to the traditional soldering stations. 
     Each soldering process has an optimum temperature which must be maintained within set, often specified, limits for proper soldering. The control dials on the second generation power supplies can be adjusted to provide the appropriate amount of power to obtain this optimal temperature. Before heating elements had sensors built into them, the user would have to measure the tip temperature using special thermometers, then adjust the control dials, then measure the temperature, then adjust the control dials, and so on. Using such an iterative procedure, the user would fine-tune the actual temperature until it equaled the optimal temperature. Later technology incorporated sensors within the tip itself to measure the temperature, thereby eliminating the need for the time-wasting iterative process. Accordingly, soldering stations were developed that could utilize information from sensors located in the cartridge to automatically fine-tune the power output to reach the optimal temperature. 
     The development of cartridge sensors changed the role of the power supply and the user. The sensors within the cartridge relayed information back to the power supply, and the power supply displayed the temperature on a display. However, even these new technologies encountered serious shortcomings. To begin with, the temperature sensor was not located near the tip surface used for soldering. Instead, the temperature sensor was located near the heating elements inside of the tip. As a result, the sensed temperature of the heating element within the cartridge did not reflect the true temperature of the tip. Second, because of the distance between the sensor and the tip, the temperature gradient between the sensor and the tip could often be steep. Therefore, although the automated procedures may have brought the tip temperature closer to being within range of the optimal tip temperature, the user still had to make manual adjustments and use iterative processes to narrow the range until the actual tip temperature equaled the optimal tip temperature. 
     Another solution to the temperature differentials was the use of a central processing unit (“CPU”) within the power supply to control the temperature of the heating element located inside of the tip. A user would measure the actual tip temperature using a thermometer and then calculate the difference between the actual tip temperature and the temperature setting on the soldering station. This difference was input into the CPU, and the CPU adjusted the power output according to an iterative process or preprogrammed algorithms. Although the user skill level required to measure and to calculate the difference was certainly lower than that required to adjust the dials, the process still expended valuable time. 
     A more significant issue involved the removal of a cartridge having a given tip configuration from the connector and the replacement with a cartridge having a different tip configuration. This occurs because, during the course of soldering in any given application, the user may need to change the cartridge several times to have the optimal tip configurations. Every time a cartridge is replaced, the user must go through the same iterative procedures discussed above to reach the optimal temperature. 
     Inefficient time expenditure is not the only unwanted consequence of the present state of the art. For example, if the tip temperature is not adjusted to the proper level, the soldering iron is operable to solder an application or type of solder even though the setting is unsuitable for the application or type of solder. If soldering is performed at an inappropriate temperature, the electronic component to be soldered may be damaged by the excessive heat or the solder connection could be weak if the tip was either not hot enough or too hot. Because several different cartridges and tips could-be utilized during a given soldering procedure, it is probable that a user may solder an application without waiting for the tip to reach the optimal temperature. Even if a CPU is being used to adjust the tip temperature, the difference between the actual temperature and the optimal temperature must be input, until the difference is de minimis. Clearly, performing competent soldering requires the operator to be skilled in the art of temperature adjustment as well as soldering technique. When a significant amount of time is spent adjusting the soldering temperature, the efficiency and cost performance of the soldering process is reduced. This increases the average cost of goods and decreases profit margins. 
     There is thus a need in the soldering industry to provide an easier and more automated means of adjusting the tip temperature for different tips, as well as a reliable mechanism to inform the operator when the adjustment has been accomplished. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is directed to a processor-controlled automated soldering system and a method for its operation that determines the characteristics of a particular soldering cartridge tip, adjusts the output power as appropriate and provides signals to the operator to assure adjustment has been accomplished. In particular, the present invention creates an automated system of cartridge recognition, using reader and identifier technology, to preset the power output level of the power supply station. The identifier, which is attached to the cartridge, contains encoded information about the various properties of the cartridge and its tip such as for example the offset value of the tip. A reader associated with the power supply station is able to read the information from the identifier and communicate it to a CPU within the power supply station. The power supply station can thus generate power using the proper offset according to the particular cartridge tip to be used. Also included in the present invention is an output device that displays a first light pattern when the cartridge is not ready to be heated and a different light pattern when the cartridge is ready to use. 
     Accordingly, an automated soldering system is set forth which includes cartridges capable of storing encoded information in an identifier, a reader having means to read the information in the identifier, a CPU adapted to process various data and match cartridge information with look-up tables, and a power cable having a connector including means of visually displaying signals received from the CPU. An intelligent and automated power supply is thus provided to transmit variable rates of power to power the cartridge. 
     To use and operate the automated soldering system, an operator first chooses the appropriate cartridge for a given soldering task, each such cartridge having encoded information positioned proximate the end opposite the tip. The operator then sets the desired soldering temperature which is displayed on the soldering station. The identifier end of the cartridge is inserted into a reader in the power stations which reads the information such as the cartridge offset value and transfers it to the CPU. According to the cartridge offset or various look up tables and stored data, the CPU determines the corresponding level of power to be generated to properly heat the respective tip and communicates this information to the power supply to program its output level. Even though the power supply has received instructions to supply power, it will not initiate power generation until a closed circuit is established, which indicates that the cartridge has been properly inserted into the connector of the power cable. 
     An LED indicator located on the connector blinks on and off if the power supply is on and a cartridge has not been inserted into the reader. Once a cartridge is inserted into the reader and its information is obtained, the LED indicator turns on to indicate that the power supply is calibrated. 
     If the cartridge is disconnected from the connector of the power cable, the resulting open circuit will cause the power supply to reset and the LED indicator located on the connector blinks on and off. To reinitiate power generation, the procedure detailed above must be followed with the same or a different cartridge. 
     The above described and many other features and attendant advantages of the present invention will become apparent from a consideration of the following detailed description in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A detailed description of the invention will be made with reference to the accompanying drawings wherein: 
     FIG. 1 shows a perspective view of the soldering system including a cartridge assembly, power supply, a reader and a power cable coupling the cartridge to the power supply; 
     FIG. 2 is a block diagram indicating the flow of information within the soldering system of FIG. 1; 
     FIG. 3 depicts the cartridge, handle assembly and connector of the power cable; 
     FIG. 4 is a side and partial cross-sectional view of the connector; 
     FIG. 5 is a frontal view of the reader on the power supply; 
     FIG. 6 is a side view of the reader of the power supply; 
     FIG. 7 is a cross-sectional view of the reader depicting the sensors and switch inside of the power supply; 
     FIG. 8 shows a cartridge just before it is inserted into a cross-sectional view of the reader; and 
     FIG. 9 shows a cartridge inserted into a cross-sectional view of the reader. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 depicts a perspective view of an automated soldering system  10  according to the present invention. The automated soldering system  10  includes a power supply  12  that supplies current and power to a soldering cartridge  20  through a power cable  14  terminating at a connector  16 . The power cable  14  couples the cartridge  20 , inserted into the connector  16  located at the proximal end of the power cable  14 , with the power supply  12 . Inside the power cable  14  are numerous individual wires, each coated with insulation, bundled together and wrapped with a plastic or rubber sheath. Attached to the distal end of the power cable  14  is an electrical connector  28  that has pins (not shown), each associated with a wire inside of the power cable  14 . The electrical connector  28  connects to a coupling jack  26  located on the power supply  12 . The end opposite the electrical connector  28  is adapted to receive a cartridge assembly  18 , which includes a handle  22  and the cartridge  20 . The power supply  12  contains a reader  24  equipped to read and decode information provided by an identifier (as described below) on the cartridge  20 . 
     FIG. 2, a block diagram of the preferred embodiment, depicts the particular components within the power supply  12  of the automated soldering station  10 . The power supply  12  includes a central processing unit or CPU  30 , a temperature display  32 , temperature set point dials  34 , and a power generator  36  in addition to the reader such as a bar code reader  24 . 
     As illustrated in FIG. 3, the cartridge assembly  18  includes the handle  22  which removably slides onto the cartridge  20 . The cartridge  20  has three main visible components: a tip  42 , a cylindrically shaped housing  44  and a contact area  46  which includes electrical contacts  48  and  50  separated from the housing  44  and from each other by cylindrical insulators  52 . As depicted in FIG. 3, this cartridge  20  also includes an identifier, which is depicted as being a bar code  38 . Within the cartridge  20 , wires connected at one end to respective terminals on the inside of the electrical contacts  48 ,  50  extend through the housing  44  to a heating wire within a heating element or a sensor insider of the tip  42 . 
     The bar code  38  provides a readable code or information about the particular cartridge  20 . In the preferred embodiment, the bar code  38  provides at least an offset value or a product identification number for the particular cartridge  20 . The reader  24  is able to read the information from the identifier  38  and transmits it to the CPU  30 . The CPU  30  has various lookup tables that store many cartridge identification numbers and corresponding power generation levels. 
     To inform the CPU  30  that the user wants to use the soldering station  10 , the identifier end of the cartridge assembly  18  is inserted in the reader  24 . In response to the information provided by the reader  24 , the CPU  30  compares the cartridge information with data stored in the look-up tables. If the CPU  30  does not recognize the cartridge  20 , a LED indicator  40  will display a corresponding signal to inform the user to reinsert a known cartridge  20 . If the CPU  30  recognizes the cartridge  20 , the CPU  30  directs the power supply  12  to begin a power generation sequence and the LED indicator  40  will display a signal indicating recognition of the cartridge  20 . The power supply  12  provides a variable current and/or manipulates the number of current pulses in a given period to appropriately energize the cartridge. An indicator on the power supply  12  will display a signal corresponding to the recognition by the CPU  30  that the cartridge has been appropriately energized to the point where the tip has reached its optimal temperature. 
     To ensure safety and conserve energy, the power generator  36  will not transmit current to the cartridge  20  until the circuit including the power supply  12 , the connector  16  and the cartridge  20  is closed. The complete insertion of the cartridge  20  into the connector  16  will close the circuit and trigger a flow of current from the power generator  36  to the cartridge  20  through the power cable  14 . A heating element within the tip  42  of the cartridge  20  generates heat. A temperature sensor inside the tip  42  of the cartridge  20  will transmit temperature data to the CPU  30  through the power cable  14 . The temperature display  32  on the power supply  12  will show the desired tip temperature. The user can adjust the desired tip temperature using the set point dials  34  to provide a signal to the CPU  30  if the user desires a specific temperature and the offset information obtained by the reader  24  from the cartridge  20  provides the offset information to adjust the CPU  30  to adjust the output to the cartridge  20 . 
     Once the cartridge  20  has been inserted into the reader  24 , the LED indicator  40  will be continuously lit to provide a visual cue to the operator. The light signal informs the user that the power supply  12  is programmed for the soldering cartridge  20  and the power supply  12  is in use. If the user removes the cartridge  20  from the connector  16 , the CPU  30  will recognize that the circuit has been broken and reset the power generator  36 . The LED indicator  40  will blink on and off and current will not flow through the connector  16  until the user reinitiates the sequence described above, i.e. inserting an identifiable cartridge  20  into the reader  24  and then inserting the same cartridge  20  into the connector  16 . The same steps must be followed if the user wants to reuse a removed cartridge  20  or replace it with a new cartridge  20  during the course of soldering in any application. 
     The tip  42  of the cartridge  20  can come in many shapes and sizes to accommodate the various demands of soldering technique. Inside the tip  42  is a heating mechanism that is known in the art. Heating mechanisms also contain various temperature sensors in addition to many heating elements. When the cartridge  20  receives power from the connector  16 , the cartridge  20  will become hot from the heat generated within the tip  42 . The housing  44  of the cartridge  20  protects the wires (not shown) connecting the electrical contacts  48  and  50  in the contact area  46  of the cartridge  20  to heating mechanisms inside the tip  42 . 
     The type and location of the identifier such as the bar code  38  on the cartridge  20  will depend on parameters particular to the technology used. In the preferred embodiment, the identifier is the bar code  38 . The bar code  38  is preferably located near the distal end of the housing  44  to minimize the harmful effects from the heat generated inside the tip  42 . In alternative embodiments, the constraints of the particular technology used for the identifier may require a different placement. Moreover, the identifier could utilize other technologies such as optical scanning, magnetism, RFID, memory devices, or other contact and contact-less means to transfer information to an appropriate reader associated with the power supply  12 . 
     It should be noted that a user could insert either the cartridge  20  by itself or the cartridge assembly  18  into the reader  24  in the preferred embodiment. However, as a practical matter and for safety reasons, it is preferable if the user does not physically touch the cartridge  20 . This prevents contamination of the cartridge  20  with oils and moisture from human contact. It is preferred if the user grips the handle  22  to manipulate the cartridge  20 . 
     The LED indicator  40  is not restricted to its limitations in the preferred embodiment. In the preferred embodiment, the LED indicator  40  includes a light emitting diode (“LED”) (as described below) located within the connector  16 . In alternative embodiments, the LED indicator  40  can include various colored diodes, where each color and each color pattern has an associated meaning. For example, a green light could mean that the cartridge  20  is ready to use, whereas a red light could mean that the CPU  30  has not recognized the identifier  38  and/or that the power supply  12  has not begun transmission of power to the connector  16 . It is also contemplated that various blinking and other on/off patterns could be used to display information. Also, it is not absolutely necessary to use diodes in the LED indicator  40 . Other light producing mechanisms such as fiber optics can be used to display light patterns. The location of the LED indicator  40  does not necessarily need to be within the connector  16 , as long as the LED indicator  40  is located someplace on the soldering system  10  where it is visible to the operator, the exact location is variable. 
     FIG. 4 depicts a cross-sectional view and a side view of the connector  16  of the power cable  14 . The connector  16  has a cylindrical sleeve  62  which slopes inward to seal against the insulator of the power cable  14 . A cord bush  60  may be inserted between the cylindrical sleeve  62  and the insulator of power cable  14  to ensure that the power cable  14  is not easily removable from the connector  16 . A first wire  76  from within the power cable  14  is connected to a LED  64 . Additional wires  78  and  80  connect to the pair of wiping contacts  68  that supply current to electrical contacts  48  and  50  on the cartridge  20 . The LED  64  is positioned within an indicator window  66 . The LED  64  and the LED indicator window  66  form the LED indicator  40 . The LED  64  turns on and off according to the signals sent from the CPU  30 . The cylindrical sleeve  62  extends past the LED  64  to an end  70  defining a cylindrical opening  72  adapted to accept the contact area  46  of the cartridge assembly  20 . The cylindrical sleeve  62  is preferably made of a hard, non-flexible material designed to insulate the outside grip area. 
     FIGS. 5,  6 , and  7  depict a front view, side view and cross-sectional view of the reader  24  respectively. The reader  24  includes an opening  90  into which a cartridge assembly  18  is at inserted. The internal components of the reader  24 , which are best illustrated in FIG. 7, include a plurality of sensors  92  and a tip sensor switch  94  mounted in an assembly  96 . In the exemplary embodiment, the sensors  92  are simple bar code detectors, one sensor for each potential line of bar code. In alternative embodiments, only one sensor may be necessary or the sensors may use different technology, such as optical scanners, magnetics, RFID, memory devices, or other contact and contact-less means to receive information from the identifier. The tip sensor switch  94  detects whether the cartridge assembly  18  has been fully inserted into the reader  24  and triggers the actuation of sensors  92 . 
     As shown in FIGS. 8 and 9, the contact area  46  of cartridge  20  of the cartridge assembly  18  is inserted into the reader  24  opening  90  until the end of the cartridge  20  triggers the tip sensor switch  94 . Once the tip sensor switch  94  is activated as depicted in FIG. 9, the sensors  92  begin transmitting information to the CPU  30 . If the cartridge assembly  18  is removed, the tip sensor switch  94  is deactivated, which further deactivates the sensors  92 . 
     In the preferred embodiment, the reader  24  is located in the power supply  12 . However, in alternative embodiments, the reader  24  can be located anywhere within the soldering system  10  as long as there is a means of communication for the data received by the reader  24  and transmitted to the CPU of the power supply  12 . 
     Having thus described different embodiments of the invention, other variations and embodiments that do not depart from the spirit of the invention will become readily apparent to those skilled in the art. The scope of the present invention is thus not limited to any one particular embodiment, but is instead set forth in the appended claims and the legal equivalents thereof.