Abstract:
A cartridge system for a cartridge type soldering iron has a sleeve stopper with hooks and a sleeve which goes over the stopper. The hooks of the sleeve stopper lock with a socket assembly of the soldering iron which connects to an electrical source. A tip cartridge of the soldering iron has a tip retaining mechanism to fix the sleeve stopper with respect to the tip cartridge. The sleeve is made from a non-heat conducting material to protect a user&#39;s fingers from heat.

Description:
FIELD OF THE INVENTION 
     The present invention relates generally to a cartridge type soldering iron, and in particular to a cartridge type soldering iron having a sleeve assembly and a socket assembly which couple with each other in a locking position. 
     BACKGROUND OF THE INVENTION 
     A cartridge type soldering iron of the type at issue here has a releasable and replaceable tip cartridge. For example, a cartridge type soldering iron is disclosed in U.S. Pat. No. 4,839,501 issued to Cowell. Cowell discloses a cartridge type soldering iron which has a hollow cylindrical handle, incorporating an internal coaxial socket assembly, a connection to a power supply, and a cartridge housing support, and a soldering tip, a heater assembly, a tubular housing and a coaxial socket assembly. Another is disclosed in U.S. Pat. No. 6,710,304 to Yokoo, entitled cartridge type soldering iron with a releasable and replaceable handle. 
     SUMMARY OF THE INVENTION 
     A cartridge type soldering iron according to the present invention provides a sleeve, a sleeve stopper, a tip cartridge and a socket assembly. The sleeve stopper has a stop and when it is inserted into the sleeve, the sleeve abuts the stop. The sleeve stopper is fixed with respect to the tip cartridge by a tip retaining mechanism provided on the tip cartridge. A socket assembly of the soldering iron defines apertures with which the hooks of the sleeve stopper respectively engage so that the sleeve stopper and the socket assembly are fixed with respect to each other. 
     The sleeve can be of any color and can have a circular, hexagonal or polygonal circumference, although its shape can vary as long as it is easy to grip and functions well as a sleeve. The sleeve is made of a non-slip material for an easy and accurate grip and generally non-heat conducting for protection of a user&#39;s fingers. 
     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 when considered in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A detailed description of exemplary embodiments according to the invention will be made with reference to the accompanying drawings. 
         FIG. 1  shows a hexagonal sleeve of a cartridge soldering iron according to the present invention; 
         FIG. 2 . shows a sleeve stopper according to the present invention; 
         FIG. 3  shows the sleeve stopper of  FIG. 2  in another view; 
         FIG. 4  shows the hexagonal sleeve of  FIG. 1  coupled with the sleeve stopper shown in  FIGS. 2 and 3 ; 
         FIG. 5  shows a tip cartridge employed in the present invention; 
         FIG. 6  shows the sleeve stopper and the sleeve engaged with the tip cartridge; 
         FIG. 7  shows a socket assembly of the soldering iron according to the present invention; 
         FIG. 8  shows the soldering iron with the sleeve and the sleeve stopper according to the present invention; 
         FIG. 9  shows a side view of a circular sleeve of the present invention; and 
         FIG. 10  shows a cross-sectional view of the soldering iron of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     This description is not to be taken in a limited sense, but is made for the purpose of illustrating the general principles of the present invention. The section titles and overall organization of the present detailed description are for the purpose of convenience only and are not intended to limit the present invention. 
       FIG. 1  illustrates by way of example a sleeve  1  for use with a cartridge type soldering iron according to the present invention. The sleeve  1  has a plurality of ridges  3 ,  5  extending longitudinally, which in this embodiment is hexagonal in circumference. A smooth circular sleeve can also be adopted as well as any other shape as long as the sleeve provides a good grip and is compatible with a below-described sleeve stopper.  FIG. 9  shows a cross-sectional view of a circular sleeve  16  of the present invention. The circular sleeve  16  of  FIG. 9  is shown from a distal end  15   a  of the circular sleeve  16 . It has a circular outer circumference  17  and another circular interior circumference  18 . A plurality of ridges  19  are provided on the interior circumference  18  which run in the longitudinal direction of the circular sleeve  16 . There are six ridges  19  provided in this particular embodiment of the circular sleeve  16  shown in  FIG. 9 . These ridges  19  function as a heat insulator to retard the heat conduction from the heater. 
     In the hexagonal sleeve  1  of  FIG. 1 , a distal end  15  ends abruptly while the other end slopes down to a narrower circumference at shoulders  9  and  13  and extends into two tips  7 ,  11 , respectively. In  FIG. 9 , the circular sleeve  16  has corresponding tips  7   a  and  11   a.    
     In the embodiments of the present invention shown here, the sleeves  1  and  16  are made of polypropylene. The sleeves  1  and  16  may also be made of a variety of materials that are known to those skilled in the art. These materials include rubber, elastomer and polyolefin and other plastics. Further, an anti-static material and/or an anti-microbial material may be added. Additionally, instead of polypropylene, cork can be used in its place. 
       FIGS. 2 and 3  show the sleeve stopper  21  having a stop  27  at one end and a pair of hooks  24  at the other end. The hooks  24  have buttons  24   a  and hook tips  23 . A pair of steps  29  and  31  is provided on the body of the sleeve stopper  21  to help provide a snug fit with the sleeve  1 . The sleeve stopper  21  defines a pair of apertures  33 . A couple of O rings  25  are provided as well. The sleeve stopper  21  slidably couples with the sleeve  1  where hooks  24  are positioned between the tips  7 ,  11 , respectively, as shown in  FIG. 4 . When the sleeve  1  is inserted over the sleeve stopper  21 , the end  15  of the sleeve  1  abuts and is fixed against the stop  27  of the sleeve stopper  21 . 
     The sleeve stopper  21  may be made from an insulating material, for instance, if the heat conduction is such that the sleeve stopper area gets hot from the heat of the tip. The stop  27  of the sleeve stopper  21  may be made from a temperature-sensitive material so that as the soldering iron tip heats up, it indicates to the user of its readiness or burn risk depending on a degree of temperature sensitivity by changing color. 
       FIG. 5  shows a tip cartridge  35  employed in the present invention. The tip cartridge  35  has two ridges  37  and  39  defined in its body and bar codes  41 ,  42 ,  43 . The bar codes  41 ,  42 ,  43  identify the type of tip cartridge and its corresponding temperature requirement and are provided on a stainless portion  47  of the tip cartridge  35 . A couple of contact points  44  and  45  are provided on a non-electrically conductive material  46 . The ridge  39  on the tip cartridge  35  is used as a tip retaining mechanism. When the tip cartridge  35  is inserted into the sleeve stopper  21 , the ridge or the tip retaining mechanism  39  comes to rest at a certain point of the sleeve stopper  21  as can be seen in a cross-sectional view of  FIG. 6 . The tip cartridge  35  in this way is fixed with respect to the sleeve stopper  21 . The O rings  25  bind the arms  22  to the extent shown in  FIG. 3 , which leaves a predetermined amount of space between the arms  22 . The arms  22  are bound to such an extent so that the hooks  24  slidably hook with the socket assembly  70  at the corresponding apertures  40  and stay hooked through normal use of the solder iron. The O rings  25  also bind to retain and secure the tip cartridge  35  with enough force for the tip cartridge  35  to slidably fit within the sleeve stopper  21  but at the same time to stay secured and not come apart as it sometimes did in prior art systems. 
     Next, the sleeve stopper  21  is locked with the socket assembly  70  in a following manner. As described above, the sleeve stopper  21  according to the present invention is provided with a pair of hooks  24 . When the sleeve assembly composed of the sleeve stopper  21  and the sleeve  1  holds the tip cartridge  35 , and the whole combination is inserted into the socket assembly  70 , the hook ends  23  slidably lock with the apertures  40  of the socket assembly  70 . A cross sectional view of the assembled soldering iron is shown in  FIG. 10 . 
     The socket assembly  70  has a plug (not shown) at the end of an electrical cord  80  to connect to the power source.  FIG. 10  shows the socket assembly  70  in its cross-sectional view and shows a connector  90 . The contact points  44  and  45  of the tip cartridge  35  are connected with the connector  90  for supplying the power to the tip cartridge  35 . 
     In prior art systems, a socket assembly sometimes comes apart from the rest of the soldering iron. Such disconnection is caused by insufficient fastening or coupling between the socket assembly and the rest of the cartridge type soldering iron. This results because the tip cartridge by itself or together with the rest of the cartridge type soldering iron are simply inserted into the socket assembly and has insufficient mechanical hold onto the socket assembly. 
     Unlike those types of cartridge type soldering irons, the soldering iron according to the present invention provides a firm, sturdy mechanical coupling between the sleeve assembly on one hand and the socket assembly on the other, through the above-described provision of the locking mechanism. Therefore, the entire cartridge type soldering iron can stay together, and at the same time, the assembly of the tip cartridge with the sleeve stopper and the sleeve may easily replaced. 
     The cartridge soldering iron of the present invention is easy to use because the locking mechanism is located above the sleeve  1  and out of the way of the grip. Its parts such as the buttons  24   a , hook tips  23  are very small and almost flush with the rest of the longitudinal covered surface of the soldering iron. 
     The practical embodiments described herein are mere examples for illustrating the art of the invention, and the invention is not limited to the foregoing examples alone but should be interpreted in a wider sense including the changes and modifications falling within the scope and spirit of the invention as well as the descriptions in the claims.