WO2022123369A1

WO2022123369A1 - Gas operating system for bump-fired fastener-driving tool

Info

Publication number: WO2022123369A1
Application number: PCT/IB2021/060770
Authority: WO
Inventors: Joseph Adams
Original assignee: Joseph Adams
Priority date: 2020-12-09
Filing date: 2021-11-19
Publication date: 2022-06-16

Abstract

A gas-operated bump-fired fastener-driving tool having a main valving mechanism that is relatively light in weight and/or relatively small in mass so that it can be easily and quickly moved between its open and closed positions by way of a relatively small amount of power.

Description

GAS OPERATING SYSTEM FOR BUMP-FIRED FASTENER-DRIVING TOOL

PRIORITY

[0001] This application claims priority to and the benefit of U.S. Patent Application No. 63/199,136, which was filed on December 9, 2020, the entire contents of which is incorporated herein by reference.

FIELD

[0002] The present invention relates generally to fastener-driving tools, and more particularly to a gas-operated bump-fired fastener-driving tool.

BACKGROUND

[0003] Fastener-driving tools are of course well-known in the art. Two modes of operation of fastener-driving tools are bump-fired fastener-driving tools, whereupon each time that the nose of the tool encounters a workpiece, the tool fires a fastener into the workpiece, and sequentially-fired fastener-driving tools whereupon each time a workman pulls a firing trigger, the tool fires a fastener into the workpiece. A critically important characteristic of certain of these fastener-driving tools is the time required to recycle the tool such that the tool can again be ready to fire another fastener into another portion of the workpiece or into a different workpiece when a workman presses the nose of tool against the workpiece or pulls the trigger to fire the tool. As far as the inventor of this invention knows, no gas-operated bump-fired fastener-driving tool exists. An integral component of the firing system of certain existing bump- fired fastener-driving tools is the recycling valve system whereby a main valve is initially moved to its OPEN position from its original START or CLOSED position so as to permit air to be initially ingested into the combustion chamber of the tool as well as to exhaust or scavenge any combustion products which may be present within the combustion chamber as a result of the ignition of a previous air-fuel mixture, the valve is then moved back to its CLOSED position so as to effectively seal the combustion chamber, fuel is then injected into the combustion chamber, and then the air-fuel mixture is ignited so as to move a power piston, integrally connected to a fastener driving rod, through its power stroke so as to drive a fastener into the workpiece. [0004] One major drawback with certain conventional gas-fired fastenerdriving tools however, is the fact that the main valving mechanism is relatively massive, requires a large amount of electrical power to move it between the OPEN and CLOSED positions, and therefore, the rapidity at which the gas-fired fastener tool can effectively be recycled for new fastener-driving operations is significantly slow. Another drawback of certain conventional gas-fired fastener-driving tools is that different control mechanisms are utilized for controlling various different components of the tool, such as, for example, the valving system, the ignition system, and the fuel injection system.

[0005] A need therefore exists in the art for a new and improved gas- operated bump-fired fastener-driving tool. An additional need exists in the art for a new and improved gas-operated bump-fired fastener-driving tool wherein the main valving mechanism is relatively light in weight or comprises a relatively small amount of mass so that it can be easily and quickly moved between its OPEN and CLOSED positions by way of a relatively small amount of power. A further need exists in the art for a new and improved gas-operated bump-fired fastener-driving tool wherein, in addition to the main valving mechanism being relatively light in weight or comprising a relatively small amount of mass so that it can be easily and quickly moved between its OPEN and CLOSED positions by way of a relatively small amount of power, the various different components of the tool, such as, for example, the valving system, the ignition system, and the fuel injection system, can be controlled by a central control module which may be, for example, a programmable logic computer (PLC), a central processing unit (CPU), or the like.

OVERALL OBJECTIVES OF THE INVENTION

[0006] An overall objective of the present invention is to provide a new and improved gas-operated bump-fired fastener-driving tool. An additional overall objective of the present invention is to provide a new and improved gas-operated bump-fired fastener-driving tool wherein the main valving mechanism is relatively light in weight or comprises a relatively small amount of mass so that it can be easily and quickly moved between its OPEN and CLOSED positions by way of a relatively small amount of power. A further overall objective of the present invention is to provide a new and improved gas-operated bump-fired fastener-driving tool wherein, in addition to the main valving mechanism being relatively light in weight or comprising a relatively small amount of mass so that it can be easily and quickly moved between its OPEN and CLOSED positions by way of a relatively small amount of power, the various different components of the tool, such as, for example, the valving system, the ignition system, and the fuel injection system, can be controlled by a central control module which may be, for example, a programmable logic computer (PLC), a central processing unit (CPU), or the like.

SUMMARY

[0007] The foregoing and other objectives are achieved in accordance with the teachings and principles of the present invention through the provision of a new and improved gas-operated bump-fired fastener-driving tool which in various embodiments include a combustion chamber, a power piston disposed within a piston cylinder and having a piston head, an upper surface portion of which is exposed to or disposed within the combustion chamber, and a fastener-driving piston rod fixedly connected to a lower surface portion of the piston head and adapted to drive a fastener into a workpiece when the power piston is moved through its power stroke. A solenoid- controlled dual shuttle-valve assembly is operatively connected to the combustion chamber and is moved between OPEN and CLOSED positions so as to permit air to be ingested into the combustion chamber as well as to permit exhaust gases to be scavenged out from the combustion chamber. A fuel injector is fluidically connected to the combustion chamber for injecting fuel into the combustion chamber, and an ignition coil is electronically connected to an ignition device disposed within the combustion chamber so as to ignite an air-fuel mixture within the combustion chamber. The solenoid-controlled dual shuttle-valve assembly, the fuel injector, and the ignition coil are all electronically connected to a central control module which may be, for example, a programmable logic computer (PLC), a central processing unit (CPU), or the like, whereby the functioning of the solenoid-controlled dual shuttle-valve assembly, the fuel injector, and the ignition coil are all controlled and precisely timed by way of the central control module. An exhaust valve is also operatively associated with the piston cylinder so as to permit air, disposed beneath the power piston within the piston cylinder, to escape as the power piston is driven through its power stroke.

BRIEF DESCRIPTION OF THE DRAWINGS [0008] Various other features and attendant advantages of the present invention will be more fully appreciated from the following detailed description when considered in connection with the accompanying drawings in which like reference characters designate like or corresponding parts throughout the several views, and wherein:

[0009] FIGURE 1 is a schematic view of a new and improved gas operating system for a fastener-driving tool of one example embodiment of the present disclosure wherein the various components of the system are disclosed at their START positions immediately before a fastener-driving operation of the tool is initiated, wherein it is seen that the solenoid-controlled dual shuttle-valve mechanism is disposed at its CLOSED position;

[0010] FIGURE 2 is a schematic view similar to that of FIGURE 1 , showing for the example embodiment of FIGURE 1 , the solenoid-controlled dual shuttle-valve assembly disposed at its OPEN position so as to permit air to be ingested into the combustion chamber while simultaneously, combustion products from a previous combustion cycle are exhausted out from the combustion chamber;

[0011] FIGURE 3 is a schematic view similar to that of FIGURES 1 and 2, showing for the example embodiment of FIGURE 1 , the solenoid-controlled dual shuttle-valve assembly disposed at its CLOSED position so as to seal the combustion chamber and then permit fuel to be injected into the combustion chamber;

[0012] FIGURE 4 is a schematic view similar to that of FIGURES 1-3, showing for the example embodiment of FIGURE 1 , however, the solenoid-controlled dual shuttle-valve assembly disposed at its CLOSED position, the air-fuel mixture has been ignited, the power piston is driven through its power stroke so as to drive a fastener into a workpiece, and the exhaust valve operatively associated with the piston cylinder has been OPENED so as to permit the exhaust of air, disposed within the piston cylinder beneath the piston head of the power piston, to be exhausted out from the piston cylinder; and

[0013] FIGURE 5 is a schematic view of a new and improved gas operating system for a fastener-driving tool of another example embodiment of the present disclosure wherein the various components of the system are disclosed at their START positions immediately before a fastener-driving operation of the tool is initiated, wherein it is seen that the solenoid-controlled dual shuttle-valve mechanism is disposed at its CLOSED position. DETAILED DESCRIPTION OF VARIOUS EXAMPLE EMBODIMENTS

[0014] Referring now to the drawings, and more particularly to FIGURE 1 thereof, the new and improved gas operating system for a bump-fired fastener-driving tool of one example embodiment of the present disclosure is disclosed and generally indicated by the reference character 100. More particularly, the system 100 comprises a piston cylinder 102 within which there is disposed a power piston. The power piston includes a piston head 104 to an undersurface portion of which a fastener-driving piston rod 106 is fixedly connected so as to drive a fastener into a workpiece when the power piston is moved through a power stroke within the piston cylinder 102. An exhaust valve 108 is operatively associated with the piston cylinder 102 so as to permit air, disposed beneath the piston head 104 within the piston cylinder, to escape or be exhausted as the power piston is moved downwardly through its power stroke as will be more fully discussed hereinafter.

[0015] A combustion chamber 110 is defined within an upper portion of the tool housing 112, and it is seen that a first fan 114 is disposed within the combustion chamber 110 so as to facilitate mixing of air and fuel within the combustion chamber 110 when both air and fuel are respectively ingested and injected into the combustion chamber 110. The fan 114 is operatively connected to a motor 116, which is disposed atop the tool housing 112, and a second cooling fan 118 is also operatively connected to the motor 116 so as to provide cooling for the tool housing 112.

[0016] Continuing further, a solenoid-controlled dual shuttle-valve assembly 120 is operatively associated with the combustion chamber 110 and comprises an air intake valve 122 and an exhaust valve 124, wherein both valves 122,124 are mounted upon opposite ends of a valve stem or valve rod 126. The solenoid-controlled dual shuttle-valve assembly 120 is operatively connected to a solenoid 128 which moves the solenoid-controlled dual shuttle-valve assembly 120 between its OPEN and CLOSED positions, and the solenoid 128 is, in turn, electronically connected to a control module 130 which may be, for example, a programmable logic computer (PLC), a central processing unit (CPU), or the like. It is to be noted that as a result of the incorporation of the solenoid-controlled dual shuttlevalve assembly 120 within the system, the entire valve assembly 120 is relatively light in mass or weight, requires significantly less electrical power to operate or move the same between its OPEN and CLOSED positions, and therefore provides the fastener- driving tool with quick recycle times. In addition, it is also seen that the motor 116 is electronically connected to the control module 130.

[0017] Still further, the system 100 also comprises a fuel injector 132 for injecting fuel into the combustion chamber 110, wherein the fuel injector 132 is electronically connected to the control module 130, and an ignition coil 134 for sending a signal to an ignition device 136 which is disposed within the combustion chamber 110 so as to initiate ignition of an air-fuel mixture disposed within the combustion chamber 110, the ignition coil 134 likewise being electronically connected to the control module 130. Lastly, an electronic switch 138 is also electronically connected to the control module 130 such that when the switch 138 is moved from its OPEN position to its CLOSED position, a signal will be sent to the control module 130 which will, in turn, send a signal to the ignition coil 134 which will initiate ignition of the ignition device 136. The switch 138 comprises a conventional switch disposed upon bump- fired fastener-driving tools such that when the tool is placed into contact with a workpiece, the switch 138 will be moved to its CLOSED position so as to initiate the firing of the fastener-driving tool. In addition, a start switch 140 is also electronically connected to the control module so as to start or prime the fastener-driving tool after it has not been used for a while or is new, as will be more fully discussed hereinafter.

[0018] Having described all of the components of the new and improved system 100, the operation of the same will now be briefly described. It is to be noted that when the tool has not been used for a while, or is new, the electronic switch 138 will be disposed in its OPEN position. In addition, the start switch 140 will be depressed so as to send an electronic signal to the control module 130 so as to prime the tool for operation. As a result of the depression of the start switch 140, the control module 130 will send a signal to the motor 116 so as to, in turn, actuate the fans 114,118, and the solenoid 128 is actuated so as to move the solenoid-controlled dual shuttle-valve assembly 120 from its CLOSED position as illustrated within FIGURE 1 to its OPEN position as illustrated within FIGURE 2. Accordingly, fresh air will be ingested into the combustion chamber 110 through way of the OPEN intake valve 122, while exhaust products from a previous combustion cycle will be exhausted or scavenged out from the combustion chamber 110 through way of the OPEN exhaust valve 124.

[0019] Subsequently, as illustrated within FIGURE 3, the control module 130 will cause the solenoid-controlled dual shuttle-valve assembly 120 to be moved back to its CLOSED position whereby the combustion chamber 110 is now sealed with a fresh supply of air entrapped therewithin as a result of the intake and exhaust valves 122,124 being disposed at their CLOSED positions. Accordingly, the control module 130 will now actuate the fuel injector 132 to inject a predetermined amount of fuel into the combustion chamber 110. At this point in time, the tool is now ready to be fired.

[0020] Therefore, when the tool is disposed in contact with a workpiece, the bump-firing switch 138 will be closed, as illustrated within FIGURE 4, whereupon the control module 130 will transmit an electronic signal to the ignition coil 134 which will, in turn, send an electronic signal to the ignition device 136 disposed within the combustion chamber 110 so as to initiate ignition of the air-fuel mixture disposed within the combustion chamber 110. As a result of the ignition of the air-fuel mixture disposed within the combustion chamber 110, and as can be best appreciated from FIGURE 4, the power piston will be moved downwardly within the piston cylinder 102 so as to be driven through its power stroke whereby a fastener will be driven into a workpiece. The exhaust valve 108 operatively associated with the piston cylinder 102 will be moved to its OPEN position so as to permit air, disposed beneath the piston head 104, to escape or be exhausted out from the piston cylinder 102. At the completion of the power stroke, the piston is returned to its original or START position either by known vacuum techniques or assistance techniques, such as, for example, the use of compressed air charged into the piston cylinder 102 so as to force the piston upwardly to its original or START position. If another bump-firing operation is commenced within a predetermined period of time, then each time the bump-firing switch 138 is moved to its CLOSED position, the control module 130 will actuate the motor 116, the solenoid 128, the fuel injector 132, and the ignition coil 134 in a pre-determinedly timed sequence. If the tool is not used for a predetermined period of time, then the original priming mode of operation is again initiated by way of the start button 140, and then when the bump-firing switch 138 is activated, the tool will fire a fastener into a workpiece.

[0021] Obviously, many variations and modifications of the present invention are possible in light of the above teachings.

[0022] For example, the control module 130 can comprise various different software which can also render the tool a sequentially-fired tool, and will therefore control the timed actuation of the solenoid 128, the fuel injector 132, and the ignition coil 134, as well as the operation of the motor 116 which drives the first and second fans 114,118. in an appropriate manner. [0023] Another example alternative embodiment of the present disclosure is shown in FIGURE 5. This alternative embodiment of the present disclosure does not include the cooling fan 118 described above. Thus, this alternative example embodiment of the system 100 includes all of the other components described above. Specifically, this alternative example system 100 includes: (1) a piston cylinder 102; (2) a piston head 104; (3) a fastener-driving piston rod 106; (4) an exhaust valve 108; (5) a combustion chamber 110; (6) a tool housing 112; (7) a fan 114; (8) a motor 116; (9) a solenoid-controlled dual shuttle-valve assembly 120; (10) an air intake valve 122; (11) an exhaust valve 124; (12) a valve stem or valve rod 126; (13) a solenoid 128; (14) a control module 130; (15) a fuel injector 132; (16) an ignition coil 134; (17) an ignition device 136; (18) an electronic switch 138; and (19) a start switch 140. This alternative example embodiment will operate in an similar manner to the manner described above, except that, as a result of the depression of the start switch 140, the control module 130 will send a signal to the motor 116 so as to, in turn, actuate the fan 114 (but not fan 118 because fan 118 is not included in this alternative embodiment).

[0024] It should be understood that each of the above different embodiments is supported by a suitable housing.

[0025] Accordingly, it is therefore to be understood that within the scope of the appended claims, the present invention may be practiced otherwise than as specifically described herein.

Claims

1. A gas operating system for a fastener-driving tool, comprising: a piston cylinder; a power piston movably disposed within said piston cylinder; a combustion chamber; a solenoid-control dual shuttle-valve assembly operatively associated with said combustion chamber and comprising an intake valve for permitting fresh air to enter said combustion chamber, and an exhaust valve for permitting combustion products to be exhausted from said combustion chamber, wherein said solenoid-control dual shuttle-valve assembly is movable in opposite directions so as to permit said intake and exhaust valves to be moved between OPEN and CLOSED positions; a fuel injector for injecting fuel into said combustion chamber; an ignition device for igniting an air-fuel mixture within said combustion chamber; and a control module electronically connected to said solenoid-control dual shuttle-valve assembly, said fuel injector, and said ignition device for controlling said solenoid-control dual shuttle-valve assembly, said fuel injector, and said ignition device during an operation cycle wherein said power piston is driven through a power stroke so as to drive a fastener into a workpiece.

2. The system as set forth in Claim 1 , wherein: said control module comprises software so as to pre-determinedly control the activation of said solenoid-control dual shuttle-valve assembly, said fuel injector, and said ignition device at various different times.

3. The system as set forth in Claim 2, wherein: said control module comprises software so as to pre-determinedly control the activation of said solenoid-control dual shuttle-valve assembly, said fuel injector, and said ignition device in various different modes.

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4. The system as set forth in Claim 3, wherein: said control module comprises software so as to pre-determinedly control the activation of said solenoid-control dual shuttle-valve assembly, said fuel injector, and said ignition device in various different modes such that said tool comprises a bump-fired fastener-driving tool.

5. The system as set forth in Claim 4, wherein: said bump-fired fastener-driving tool comprises a bump-fired switch for sending an electronic signal to said control module so as to initiate the firing of said bump-fired fastener-driving tool.

6. The system as set forth in Claim 3, wherein: said control module comprises software so as to pre-determinedly control the activation of said solenoid-control dual shuttle-valve assembly, said fuel injector, and said ignition device in various different modes such that said tool comprises a sequentially-fired fastener-driving tool.