Abstract:
A bolt mechanism that is actuated by an electromagnetic arrangement is provided for use within a pneumatic projectile launcher or marker. The electro-magnetic arrangement provides for rapid movement and a high degree of control over the bolt. Generally, an arrangement of electro-magnetic coils is provided that exert a force on ferrous materials or permanent magnets thereby causing the bolt to reciprocate back and forth. Several embodiments are provided that disclose configurations having varied numbers of electromagnetic coils, ferrous materials and permanent magnets strategically placed within the breech and bolt of the marker, wherein energizing the coils produces movement of the bolt. Further, the electro-magnetic bolt system of the present invention is equally applicable to slide bolts as well as rotary bolts.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is related to and claims priority from earlier filed U.S. Provisional Patent Application No. 60/545,400, filed Feb. 17, 2004, the contents of which are incorporated herein by reference. 

   BACKGROUND OF THE INVENTION 
   The present invention relates generally to pneumatically operated projectile launchers. More specifically, the present invention relates to an electro-magnetically operated bolt configuration for use in firearms and other projectile launchers, such as pneumatically operated projectile launchers. 
   In general, in the prior art, it is well known to utilize a pneumatically operated projectile launcher to propel a projectile at a target. Further, such a device is typically referred to as either a paintball gun or a marker. Accordingly, for the purpose of this application, the term marker will be utilized throughout this application to define a paintball gun or a pneumatically operated projectile launcher. While the present invention is discussed in connection with paintball guns, it has application in any type of projectile launching device. 
   There are a wide variety of markers available in the prior art having different configurations and manners of operation. Regardless of the configuration or mode of operation utilized by any particular marker, the general purpose of the marker is to utilize pneumatic force to launch a fragile spherical projectile containing colored marker dye, known as a paintball, at a target. When the paintball impacts upon the target, the paintball bursts releasing the marker dye onto the target thereby providing visual feedback that the target was, in fact, hit by the paintball. In this regard, before the paintball can be launched by the marker, a paintball must be first loaded into the firing chamber or breech of the marker in preparation for the release of a burst of air that ultimately launches the paintball. 
     FIGS. 1-3  generally illustrate the paintball loading operation of a prior art marker  10 . The marker  10  can be seen to include a breech  14 , a barrel  16  extending from one side of the breech  14 , a reciprocating bolt  18  that is slidably received in the breech  14  in alignment with the barrel  16  and a feed port  20  to allow paintballs  12  to be loaded into the breech  14  of the marker  10 . In operation, paintballs  12  are loaded in to the barrel  16  of the marker  10  by means of the bolt  18 . The bolt  18  is arranged to move back and forth below the feed port  20  allowing paintballs  12  to pass, one at a time, through the feed port  20  and into the breech  14 . The bolt  18  then moves forward, pushing the paintball  12  into the barrel  16  opening. Generally, these prior art devices rely on either manual operation of the bolt, mechanical valves or electronic solenoid valves that alternately switch compressed gas back and forth between the two sides of a double-acting pneumatic cylinder to move the bolt  18  for loading the paintballs  12 . Such prior art pneumatic actuation of a bolt is well known in the art and need not be discussed in detail herein. 
   In order to illustrate the operation of the bolt  18 ,  FIGS. 1-3  show a cross-sectional view of the breech  14  of a prior art marker  10  that includes a reciprocating bolt mechanism  18 . In  FIG. 1  the bolt  18  is show at rest in a position that would result immediately after firing a paintball  12  or prior to loading the initial paintball  12 . Turning now to  FIG. 2 , the bolt  18  is shown after being moved in a rearward position. With the bolt  18  in this position, the feed port  20  is opened to allow a paintball  12  to drop into the breech  14 .  FIG. 3  then shows the bolt  18  after it has returned to the forward position having pushed the paintball  12  into the opening of the barrel  16 , where it can be propelled by a pneumatic charge down the barrel  16  and launched out of the marker  10 . 
   The difficulty is that markers that rely on mechanically or pneumatically driven reciprocating bolts suffer from mechanical limitations that inherently limit the maximum rate of fire that the marker can achieve. Specifically, the ultimate cycle speed of a pneumatically operated bolt is limited by the speed at which the solenoids in the air system can be sequentially opened and closed. 
   There is therefore a need for a bolt mechanism that overcomes the inherent limitations found in the prior art, thereby allowing the bolt mechanism to cycle faster, ultimately resulting in a marker that has a higher firing rate. There is a further need for a bolt mechanism that can be more precisely controlled than prior art bolts. 
   BRIEF SUMMARY OF THE INVENTION 
   In this regard, the present invention provides for a novel bolt mechanism that overcomes many of the problems with the prior art bolts identified above. In particular, the present invention provides a bolt mechanism that is actuated by an electro-magnetic arrangement, which provides for rapid movement of the bolt as well as a high degree of control over the bolt. The use of electro-magnetic force instead of electronic solenoids and a pneumatic piston to actuate the bolt in a marker is a departure from the known prior art and provides numerous advantages that result in a marker having higher reliability and improved performance. 
   As will be discussed in detail below, the base concept of the present invention is to utilize an arrangement of electro-magnetic coils that exert a force on ferrous materials or permanent magnets thereby causing the bolt to reciprocate back and forth. In one embodiment, a piece of ferrous material or a permanent magnet is installed into the body of the bolt and at least one electro-magnetic coil is installed in the wall of the breach adjacent the bolt. Application of an electrical charge to the electro-magnetic coil serves to attract or repel the magnet in the bolt, causing the bolt to be moved. In other embodiments, at least one coil is provided in the body of the bolt and at least one magnet or piece of ferrous material is installed in the wall of the breech, adjacent the bolt. In further embodiments, multiple electro-magnetic coils are utilized to increase the overall force exerted on the permanent magnet or ferrous material, thereby enhancing the speed at which the bolt can be moved. In another embodiment, the magnet or ferrous material is positioned adjacent the bolt in a chamber of its own with electro-magnetic coils placed within the walls of the chamber. The magnet or ferrous material is connected to the bolt by a linkage so that movement of the magnet or ferrous material results in movement of the bolt. In yet a further embodiment, the present invention provides for a rotary action bolt that includes at least one permanent magnet or piece of ferrous material mounted therein with an array of electromagnetic coils disposed around the wall of the breech surrounding the bolt. As each of the electromagnetic coils is activated by applying an electrical charge, the coils attract or repel the magnet or ferrous material, causing the rotary bolt to rotate. 
   In addition to the electro-magnetic system as described above, various sensors may also be incorporated into the marker and electrically coupled to the control system within the marker thereby providing unprecedented control over the bolt that was not previously possible with known pneumatic systems. As a result, the electronic operating system of the marker can more precisely control the loading and launching of the projectile. 
   As can be seen in view of the above, a new and novel electro-magnet bolt control system is provided. Further, a new and novel method of actuating a bolt within a marker without the use of pneumatics or electronically operated solenoid valves is shown. The use of electro-magnetic force as provided in the present invention allows for precise control of the travel of the bolt within a marker unlike the poor control capable of with a pneumatically piston-controlled bolt. 
   It is therefore an object of the present invention to provide an electro-magnetically operated bolt transport system for use in a pneumatic projectile launcher or marker. It is a further object of the present invention to provide an electro-magnetically operated bolt, wherein electro-magnetic coils are utilized to attract and/or repel a piece of ferrous material or permanent magnet thereby causing movement of the bolt. It is yet a further object of the present invention to provide an electro-magnetically operated bolt, wherein multiple electro-magnetic coils are utilized in conjunction to move a piece of ferrous material or permanent magnet thereby causing movement of the bolt. It is an even further object of the present invention to provide an electro-magnetic bolt control system that is equally applicable to both a slide bolt and a rotary bolt. It is still a further object of the present invention to provide sensors that are integrated with an electro-magnetically operated bolt system to facilitate a high degree of control over the movement of the bolt. 
   These together with other objects of the invention, along with various features of novelty, which characterize the invention, are pointed out with particularity in the claims annexed hereto and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there is illustrated a preferred embodiment of the invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the drawings which illustrate the best mode presently contemplated for carrying out the present invention: 
       FIG. 1  is a cross-sectional view of a prior art pneumatic projectile launcher with the bolt in a closed position; 
       FIG. 2  is a cross-sectional view of a prior art pneumatic projectile launcher with the bolt in an open position and a projectile dropping into the breech; 
       FIG. 3  is a cross-sectional view of a prior art pneumatic projectile launcher with the bolt returning to a closed position, pushing the projectile into the chamber for launching; 
       FIG. 4  is a cross-sectional view of a first embodiment of the pneumatic projectile launcher of the present invention with the bolt in an open position; 
       FIG. 5  is a cross-sectional view of the pneumatic projectile launcher of  FIG. 4  with the bolt in a closed position; 
       FIG. 6  is a cross-sectional view of a second alternate embodiment of the pneumatic projectile launcher of the present invention with the bolt in an open position; 
       FIG. 7  is a cross-sectional view of a third alternate embodiment of the pneumatic projectile launcher of the present invention with the bolt in an open position; 
       FIG. 8  is a cross-sectional view of the pneumatic projectile launcher of  FIG. 7  with the bolt in a closed position; 
       FIG. 9  is a cross-sectional view of a fourth alternate embodiment of the pneumatic projectile launcher of the present invention with the bolt in a closed position; and 
       FIG. 10  is a cross-sectional view of a fifth alternate embodiment of the pneumatic projectile launcher of the present invention showing a rotary bolt. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Now referring to the drawings, as was stated above,  FIGS. 1-3  generally illustrate a pneumatic projectile launcher  10  of the prior art and the manner in which the bolt  18  is operated to load a projectile  12  in preparation for launch. As was stated above, the present invention is applicable to any projectile launcher and the disclosure of the present invention is intended to be applicable with regard to its use in any type of projectile launching device. However, for the purpose of this application, the common term marker will be used when referring to the general class of projectile launchers. 
   Turning to  FIGS. 4 and 5 , a first preferred embodiment of the electro-magnetic bolt system of the present invention is shown and generally illustrated at  100 . The bolt system  118  is shown installed in the breech  114  of a representational marker  100 . The marker  100  generally includes a receiver body  113 , a breech  114 , a barrel  16 , a feed port  20 , an electro-magnetically actuated bolt  118 , an actuator  22  and a control system  115  for controlling the operation of the marker  100 . The control system  115  can be a control unit circuit board and operating system software, which are known structures for controlling the overall operation of the marker. Further, an LED or LCD display may be provided in conjunction with the control system  115  to monitor the operation of the marker  100 . Optional control elements that interface with the control system  115  may include buttons or levers to modify settings within the marker  100  or an interface means so that the marker can be monitored by a remote device. Finally, the interface means may be through a wired connection or other wireless means that allow both monitoring and control of the marker  100  as well as allowing control programs to be downloaded into the marker  100  as desired. 
   The receiver body  113  is the central structural element of the marker  100  to which all of the other elements are connected. The breech  114  is a chamber located within the receiver body  113 . The breech  114  serves as a guide within which the bolt assembly  118  operates to direct a projectile  12  from the feed port  20  to the barrel  16  as will be further described below. The barrel  16  is a hollow tubular member that extends from one end of the receiver body  113  and is in communication with the breech  114 . The feed port  20  extends from the exterior of the receiver body  113  and into the breech  114 , providing a path along which projectiles  12  are fed into the breech  114 . Adjacent the exterior of the feed port  20  a means for containing a plurality of projectiles (not shown) is provided that serves to distribute the projectiles  12  into the feed port  20  opening. The bolt  118  of the present invention is positioned within the breech  114  and operates in a manner that controls and directs the flow of projectiles  12  from the feed port  20  into the barrel  16  for subsequent launching as will be more fully described in detail below. Finally, a handle  24  and an actuator  22 , such as a trigger, are provided and attached to the receiver body  113  providing a means by which a user can hold and activate the marker  100 . 
   In contrast to prior art markers, the present invention provides for the bolt  118  to be operated using electro-magnetic principles. In the simplest form, a first preferred embodiment of the electro-magnetic bolt  118  of the present invention is illustrated in  FIGS. 4 and 5 . In general, the principal upon which the present invention operates provides for the use of at least one magnetic coil  120  to attract or repel a permanent magnet  122  or other ferrous material. As can be seen in  FIG. 4 , a permanent magnet  122  is provided within the bolt  118  and an electro-magnetic coil  120  is positioned in the wall of the breech  114  surrounding the bolt  118 . It should be noted that magnet  122  can be completely embedded within the bolt  118 , embedded in the surface thereof or simply encircling it. When current is applied to the coil  120  in one direction, the coil  120  is energized creating a magnetic field that attracts the permanent magnet  122  within the bolt  118  causing the bolt  118  to move rearwardly as illustrated by the arrow  124 . Once the bolt  118  clears the feed port  20  opening, a projectile  12  is then allowed to drop into the breech  114 . As is best illustrated in  FIG. 5 , the control system  115  in the marker  100 , upon sensing the presence of a projectile  12  in the breech  114 , via sensors  126  within the marker  100 , reverses the polarity of the current applied to the coil  120  thereby reversing the magnetic field generated by the coil  120 . The reversed magnetic field generated by the coil  120  now serves to repel the magnet  120  within the bolt  118 , causing the bolt  118  to slide forward as is indicated by the arrow  128 , advancing the projectile  12  into the barrel  16  in preparation for launching the projectile  12 . 
   A second embodiment marker  200  that utilizes the principals of the present invention is shown in  FIG. 6 . The bolt assembly  218  in this embodiment functions in the same manner as the one described above. In this embodiment however, the positioning of the electro-magnetic coil  220  and permanent magnet  222  have been reversed. The permanent magnet  222  is installed in the sidewall of the breech  214  and the coil  220  is positioned in the bolt  218 . When electrical current is applied to the coil  220  in one direction, the coil  220  is energized causing a magnetic field that creates an attractive force between the permanent magnet  222  and the coil  220 . Since the permanent magnet  222  is in a fixed location and the bolt  218  can slide, the attractive force causes the bolt  218  to slide to an open position allowing a projectile  12  to drop from the feed port  20  into the breech  214 . As described above, when the polarity of the current applied to the coil  220  is reversed, the coil  220  repels the permanent magnet  222 , thereby causing the bolt  218  to be moved to a closed position. 
   It can be appreciated that in the configurations described above wherein a single coil is utilized, the coil must be used in conjunction with a permanent magnet so that the coil and magnet can interact to attract and/or repel one another. In other embodiments as will be described below, multiple coils may be utilized to attract and repel a permanent magnet. Further, should multiple coils be utilized, the magnet may be replaced with any ferrous material that is attracted by a magnetic field thereby allowing the coils to be operated in single direction to attract the ferrous material. For example,  FIGS. 7 and 8  show a marker  300  in accordance with a third embodiment of the electro-magnetic bolt system  318  of the present invention where a front coil  320   b  and rear coil  320   a  have been installed in the wall of the breech  314 . If a permanent magnet  322  is installed into the bolt  318 , the front coil  320   b  can be energized to repel the magnet  322  and the rear coil  320   a  can be energized to attract the magnet  322  causing the bolt  318  to slide rearwardly to an open position allowing a projectile  12  to drop through the feed port  20  and into the breech  314 . By reversing the polarity of the current on the front coil  320   b  and rear coil  320   a , the front coil  320   b  now attracts the magnet  322  and the rear coil  320   a  repels the magnet  322  causing the bolt  318  to move into a closed position where the projectile  12  is slid into the barrel  16  for launching. When constructed in this manner, the electro-magnetic force acting on the magnet  322  is doubled allowing faster and more reliable shuttling of the bolt  318  between the open and closed positions. 
   One skilled in the art should appreciate that the magnet  322  shown in  FIGS. 7 and 8  above could be replaced with a ferrous material  322 . In this configuration, the front coil  320   b  and rear coil  320   a  would be energized sequentially. To open the bolt  318 , the rear coil  320   a  is energized by the controller  115  causing the bolt  318  to slide rearwardly. To close the bolt  318 , the rear coil  320   a  is de-energized and the front coil  320   b  is energized causing the bolt  318  to slide forward. It should also be appreciated that while two coils  320   a ,  320   b  are shown herein, any possible combination of an array of a plurality of coils in combination with more than one magnet or ferrous material may be utilized to cause movement of the bolt  318 . In the broadest sense, the disclosure of the present invention is directed to moving the bolt  318  in a marker  300  utilizing electro-magnetic force. Therefore, while specific configurations are shown for the purpose of illustration the preferred embodiments of the invention, one skilled in the art can appreciated that there are literally dozens of other possible combinations wherein coils, magnets and ferrous materials are utilized to move or move a bolt mechanism in a marker, all of these combinations are intended to fall within the scope of the present disclosure. 
   By integrating sensors  126  into any of the markers illustrated herein, the controller  115  can monitor input from various points within the markers. For example, sensors  126  can be utilized to monitor the positioning of projectiles  12  within the markers or whether a projectile  12  is even present, or to monitor the position and speed at which the bolt is operating. This sensor feedback can be instantaneously processed by the controller  115  and used to quickly adjust the position of the bolt by simply energizing the coils and moving the bolt. This ability to precisely and quickly control the positioning of the bolt in response to sensor feedback was not previously available in the prior art. 
   Turning now to  FIG. 9 , a marker  400  in accordance with a fourth embodiment of the present invention is shown wherein an actuator chamber  402  is provided in the receiver body  413  adjacent the breech  414 . A linkage  404  extends from the bolt  418  into the actuator chamber  402  and terminates in either a permanent magnet  422  or a piece of ferrous material. Electro-magnetic coils  420  are provided preferably at both ends of the actuator chamber  402 , although one coil  420  may be utilized. In the same manner as described in detail above, the coils  420  are used to either attract or repel the magnet  422  or ferrous material thereby causing the linkage  404  and the bolt  418  to be moved as desired by the controller  115 . 
     FIG. 10  illustrates a marker  500  in accordance with a fifth embodiment where the principles of the present invention are employed in the context of a rotary bolt  518 . The slidable bolt that was described above has now been replaced with a bolt  518  that is configured to rotate around an axis  519  that is aligned with the longitudinal axis of the marker  500 . Again, electromagnetics are used to move a bolt for loading and launching of a projectile. The bolt  518  includes at least one seat  502  and preferably a plurality of seats  502  therein. As the bolt  518  rotates as illustrated by arrow  504 , a projectile  12  drops through the feed port  20  into one of the seats  502 . As the bolt  518  continues to rotate, the bolt  518  ultimately places the projectile  12  in alignment with the breach for launching of the projectile  12 . In this embodiment, at least one permanent magnet  522  is provided in the rotary bolt  518  and a plurality of coils  520  is provided in the walls of the receiver body  513  around the bolt  518 . The controller (not shown in this figure) sequentially energizes the coils  520  thereby attracting the magnet  522  and causing the bolt  518  to rotate as the magnet  522  is drawn to the next coil  520  in the energization sequence. Clearly, the position of the coils  520  and magnet  522  can be reversed and still be within the scope of the disclosure. Similarly, multiple magnets  522  may be utilized or ferrous material may be used in place of the permanent magnet  522  to operate the rotary bolt  518  in this embodiment in accordance with the principals disclosed above. 
   It can therefore be seen that the present invention provides an improved system for actuating a bolt within a marker using electro-magnetic forces in order to enhance the speed and reliability with which the bolt can be operated. Further by operating the bolt using electrically controlled coils in conjunction with sensors placed throughout the marker, a high degree of control over the operation of the bolt can be achieved. For these reasons, the instant invention is believed to represent a significant advancement in the art, which has substantial commercial merit. 
   While there is shown and described herein certain specific structure embodying the invention, it will be manifest to those skilled in the art that various modifications and rearrangements of the parts may be made without departing from the spirit and scope of the underlying inventive concept and that the same is not limited to the particular forms herein shown and described except insofar as indicated by the scope of the appended claims.