Abstract:
The present invention is directed to a pneumatic tool actuation device comprising a housing configured to be attached to a pneumatic tool, a piston slidably moveable within a drive chamber formed within the housing and an air inlet chamber formed within housing and configured to accept a pressurized gas and direct it to the drive chamber. The piston further comprises an O-ring disposed in an annular groove formed in the piston and forming a seal between the piston and the drive chamber. The housing is removably attached to an opening near a trigger valve pin. The air inlet chamber is operably connected to a hose through which a pressurized gas travels and enters the housing to move the piston. The movement of the piston directly actuates the trigger valve pin located in the pneumatic tool.

Description:
CROSS-REFERENCE TO RELATED APPLICATION DATA 
     This application is a continuation-in-part (CIP) of application Ser. No. 11/848,667 filed on Aug. 31, 2007, entitled Pneumatic Tool Actuation Device. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to pneumatic tools. Specifically, the present invention is directed to a pneumatic tool actuation device. 
     Pneumatic tools are becoming increasingly common in many industries, including the construction industry. Examples of pneumatic tools include pneumatic nailers, jackhammers, riveters, staplers, and the like. The operation of most pneumatically-operated tools is relatively simple: compressed air flows through a tube into the housing of the pneumatic tool and the pressure of the compressed air is used to force movement of a piston or other mechanism in the tool to do work. 
     A pneumatic tool typically is activated by depressing a trigger to drive the nails, rivets, staples, or similar fasteners from the tool. In automated applications, actuation devices are used to depress the trigger of the pneumatic tool. These actuation devices, though, can be large and involve complicated assembly. For example, known actuation devices use elaborate pulley systems; these devices, however, can be heavy and sometimes interfere with the use of the tool. In cases where the tool is relatively small, no comparably small automatic actuation devices are available. 
     Accordingly, there is a need for a simple, easy to use, lightweight pneumatic tool actuation device. Desirably, such an actuator is made of a lightweight material and is able to withstand fast, repetitive use. More desirably, such an actuator is readily made and usable, and has a high degree of integrity at minimal cost. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is directed to a pneumatic tool actuation device. The device comprises a housing configured to attach to a pneumatic tool, a piston slidably moveable within a drive chamber formed within the housing, and an O-ring disposed in a groove formed in the piston and forming a seal between the piston and the drive chamber. The housing has a gas inlet/outlet which is configured to be connected to a hose through which a gas travels and enters the drive chamber to slidably move the piston within the drive chamber. The movement of the piston directly actuates a trigger valve pin on the pneumatic tool. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The benefits and advantages of the present invention will become more readily apparent to those of ordinary skill in the relevant art after reviewing the following detailed description and accompanying drawings, wherein: 
         FIG. 1  is a left side view of the pneumatic tool actuation device in the preferred embodiment of the present invention shown attached to a pneumatic tool; 
         FIG. 2  is a right side view of the actuation device of the present invention attached to a pneumatic tool; 
         FIG. 3  is a bottom perspective view of the actuation device of the present invention attached to a pneumatic tool; 
         FIG. 4  is a top perspective view of the actuation device of the present invention; 
         FIGS. 4A and 4B  are perspective views of the actuation device of the present invention; 
         FIG. 5  is a top plan view of the actuation device of the present invention; 
         FIG. 6  is a right side plan view of the actuation device of the present invention; 
         FIGS. 6A and 6B  are right and left side views, respectively, of the actuation device of the present invention; 
         FIG. 7  is a side view of the piston element of the present invention; 
         FIG. 8  is a perspective view of first and second embodiments of the activation device in accordance with the present invention; 
         FIG. 9  is a side view of the second embodiment of the activation device illustrated in  FIG. 8 ; 
         FIG. 10  is a top view of the second embodiment of the activation device illustrated in  FIG. 8 ; 
         FIG. 11  is a side view of the second embodiment of the activation device illustrated in  FIG. 8  mounted to a small tool; 
         FIG. 12  is a perspective view of the piston element of the second embodiment of the actuation device actuating the trigger valve pin on a pneumatic tool; 
         FIGS. 13-15  are various views of the second embodiment of the actuation device showing interior portions in phantom lines. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment with the understanding that the present disclosure is to be considered an exemplification of the invention and is not intended to limit the invention to the specific embodiment illustrated. 
     It should be further understood that the title of this section of this specification, namely, “Detailed Description Of The Invention,” relates to a requirement of the United States Patent Office, and does not imply, nor should be inferred to limit the subject matter disclosed herein. 
     All patents referred to herein, are hereby incorporated herein by reference, whether or not specifically done so within the text of this disclosure. 
     In the present disclosure, the words “a” or “an” are to be taken to include both the singular and the plural. Conversely, any reference to plural items shall, where appropriate, include the singular. 
     The present invention pertains to an actuation device or actuator configured to depress a trigger on a pneumatically driven tool as illustrated in the figures. The actuator can be used on a pneumatic nailer as shown; however, it is also contemplated that the actuator can be used on other pneumatic tools and such uses should be considered to be within the scope of this invention. The actuator is configured to depress a trigger on the pneumatic tool when the actuator is actuated, thereby actuating the pneumatic tool. 
     Turning now to the figures and in particular  FIGS. 1-6 , the actuator  10  includes a housing  12  having a piston  14  disposed therein. The actuator housing  12  is a one-piece unit composed of a main body  13  and integral actuator attachment arms  22 ,  23  as seen in  FIGS. 5 and 6 . In one embodiment, as shown in  FIG. 1 , the housing  12  is configured to be used with a pneumatic nailer, such as a nailer available from ITW Industrial Fastening of Elgin, Ill., an Illinois Tool Works company. Preferably, the housing  12  is formed of a strong, durable, lightweight material, such as aluminum. 
     As the nail count in a magazine in the tool  50  is depleted, a nail follower (nail pusher) N moves toward the front or disbursal section of the nailer  50 . Thus, in a preferred embodiment, the main body  13  of the housing  12  has a triangular-shaped clearance cutout  40  formed on an outer surface of the actuator housing  12  to accommodate a follower N on a pneumatic nailer  50 . 
     A drive chamber  42  is formed as a cylindrical bore extending partially through the main body  13  of the actuator housing  12 , as shown in  FIGS. 4-7 . A piston  14  is disposed and slidably movable within the cylindrical drive chamber  42 . The piston  14  is made from brass in the present embodiment, but other materials such as steel or plastics or composites thereof are also contemplated. The material of the piston  14  should be capable of withstanding continuous and repetitive strikes/stresses, as well as stresses due to friction. 
     Actuator attachment arms  22 ,  23  are integral with the main body  13  of the actuator housing  12 . The actuator arms  22 ,  23  are spaced apart, allowing for the attachment arms  22 ,  23  to straddle the trigger housing  54  of the tool  50 . 
     The piston  14  comprises a piston head  15 , a groove G, a support plate P, and a shaft S. An O-ring  16  is disposed in the groove G of the piston  14 . The O-ring  16  acts as a seal or gasket to prevent air from escaping up along the sides of the drive chamber  42 , between the piston  14  and the drive chamber  42 . It is contemplated that the material used for the O-ring is suitable for extremes in temperature and capable of withstanding repetitive movement and/or vibration, such as a rubber O-ring as is known in the art. 
     The piston head  15  is configured to extend outwardly from actuator housing  12  through an opening formed by drive chamber  42 . In its non-actuated state, the piston head  15  is configured to lie adjacent to or in close proximity of the trigger  52  when the actuator  10  is attached to the pneumatic tool  50 . 
     An air inlet chamber  34  is formed as a cylindrical bore extending partially through the main body  13  of the actuator housing  12 , contiguous with and generally normal to drive chamber  42 . The air inlet chamber  34  is configured to accept and direct a pressurized gas to the drive chamber  42 , as discussed below. 
     The actuator  10  is attached to the pneumatic tool  50  by pins  18 ,  19 . The pins  18 ,  19  attach the actuator housing  12  to the trigger housing  54  through pin holes  20 ,  21  in the actuator housing  12  and through the trigger housing holes  56 ,  57  on the tool  50 . It is anticipated that the pneumatic tool  50  has pre-formed holes in the trigger housing  54  to accept pins  18 . However, those skilled in the art will recognized that holes may need to be formed in other pneumatic tools to attach the actuator  10  or that other attachment methods may be required depending on the design of the particular pneumatic tool. 
     Looking to  FIGS. 2 through 4 , the actuator  10  is shown with a hose  26  that carries air from a compressor (not shown) to the actuator  10 . The hose  26  has two ends, a compressor end  28  that connects the hose  26  to the air compressor, and an actuator end  30 , which comprises a brass elbow connector connecting the hose  26  to the actuator  10  at opening  30   b  formed by the air inlet chamber  34  ( FIG. 6 ) on the main body  13  of the actuator housing  12 . 
     Air from a compressor is pressurized; therefore, when a control valve is opened, or when a signal from a control system activates, air flows from the compressor through the hose  26 , through air inlet chamber  34  and into the drive chamber  42  of the actuator  10 . The pressurized air in the drive chamber  42  pushes against the support plate P of the piston  14 , forcing the piston  14  to move slidably within the drive chamber  42  and toward the trigger  52  of the pneumatic tool  50 . The piston  14  then contacts the trigger  52  of the pneumatic tool  50  and depresses the trigger  52 , thereby actuating pneumatic tool  50 . 
     After the pneumatic tool  50  is actuated, the air is released from hose  26 , and the trigger  52 , which is spring-loaded in most pneumatic tools, returns to its original position, forcing the piston  14  to retract and slidably move within the drive chamber  42  toward the housing  12  in preparation for the next actuation. As will be appreciated by those skilled in the art, a shuttle valve may be used in conjunction with the compressor to control the flow of air to and from the actuator  10 . 
     An alternate embodiment of a pneumatic tool actuation device that can be used for smaller pneumatic tools is illustrated in  FIGS. 8-15 . In  FIG. 8 , the embodiment  10  described above is shown side-by-side with the alternate embodiment  100 . 
     The actuator  100  can be used for smaller devices configured for driving staples, wires, and other like fasteners. The actuator  100  can be used to directly actuate a trigger valve pin. Actuator  100  is comprised of a housing  112  having a piston  114  disposed therein. The actuator housing  112  is a one-piece unit having a main body  113  and integral actuator attachment points  120 ,  122  as seen in  FIG. 9 . Preferably, the housing  112  is formed of a strong, durable, lightweight material, such as aluminum. 
     In this embodiment, the relatively smaller size (as seen in  FIG. 8 ) of the main body  113  precludes the need for a clearance cutout to accommodate a follower (nail pusher) on the pneumatic nailer  150 . The follower moves toward the front or disbursal section of the nailer  150  as the nail count in the magazine is depleted and easily bypasses the housing  112  of the pneumatic actuator  100 . 
     A drive chamber  142  is formed as a cylindrical bore extending partially through the main body  113  of the actuator housing  112 , as shown in  FIGS. 13-15 . A piston  114  is disposed and slidably movable within the cylindrical drive chamber  142 . The piston  114  is made from brass in the present embodiment, but other materials such as steel or plastics or composites thereof are also contemplated. The material of the piston  114  should be capable of withstanding continuous and repetitive strikes/stresses as well as stresses due to friction. 
     Actuator attachment points  120 ,  122  allow the main body  113  of the actuator housing  112  to be integrated to the pneumatic tool  150 . The actuator attachment points  120 ,  122  in this embodiment are positioned in and secured to the interior of the trigger housing  154  of the pneumatic tool  150 , as shown in  FIG. 11 . 
     The piston  114  comprises a piston head, a groove, a support plate, and a shaft similar to or the same as previously described. An O-ring  141  is disposed in the groove of the piston  114 . The O-ring  141  acts as a seal or gasket to prevent air from escaping up along the sides of the drive chamber  142 , between the piston  114  and the drive chamber  142 . It is contemplated that the material used for the O-ring  141  is suitable for extremes in temperature and capable of withstanding repetitive movement and/or vibration. 
     As shown in  FIG. 9 , the piston head  115  is configured to extend outwardly from the actuator housing  112  through an opening formed by drive chamber  142 . In its non-actuated state, the piston head  115  is configured to lie adjacent to or in close proximity of the trigger valve pin  152  when the actuator  110  is attached to the pneumatic tool  150 . 
     As shown in  FIGS. 13-15 , an air inlet chamber  134  is formed as a cylindrical bore extending partially through the main body  113  of the actuator housing  112 , contiguous with and generally normal to the drive chamber  142 , and is configured to accept and direct a pressurized gas to the drive chamber  142 . 
     The actuator  100  is attached to the pneumatic tool  150  by pins  118 ,  119 . The pins  118 ,  119  attach the actuator housing  112  to the trigger housing  154  through fastener receiving openings or pin holes  120 ,  122  in the actuator housing  112  and through the trigger housing holes  156 ,  157 . It is anticipated that the pneumatic tool  150  has pre-formed holes in the trigger housing  154  to accept pins  118 . However, those skilled in the art will recognized that holes may need to be formed in other pneumatic tools to attach the actuator  100  or that other attachment methods may be required depending on the design of the particular pneumatic tool. In this embodiment, the actual trigger of the tool need not be present. The trigger valve pin may be directly actuated by the piston. 
     When a control valve is opened, or when a signal from a control system activates, air flows from the compressor through a hose and through the air inlet chamber  134  and into the drive chamber  142  of the actuator  100 . The pressurized air in the drive chamber  142  pushes against the piston  114 , forcing the piston  114  to move slidably within the drive chamber  142  and toward the trigger valve pin  152  of the pneumatic tool  150 . The piston  114  then contacts the trigger valve pin  152  of the pneumatic tool  150  and depresses the trigger valve pin  152 , thereby actuating pneumatic tool  150 . 
     After the pneumatic tool  150  is actuated, the air is released, and the trigger valve pin  152 , which is spring-loaded in most pneumatic tools, returns to its original position, forcing the piston  114  to retract and slidably move within the drive chamber  142  toward the housing  112  in preparation for the next actuation. As will be appreciated by those skilled in the art, a shuttle valve may be used in conjunction with the compressor to control the flow of air to and from the actuator  100 . 
     From the foregoing it will be observed that numerous modifications and variations can be effectuated without departing from the true spirit and scope of the novel concepts of the present invention. It is to be understood that no limitation with respect to the specific embodiments illustrated is intended or should be inferred. The disclosure is intended to cover by the appended claims all such modifications as fall within the scope of the claims.