Fastener driving apparatus

Abstract

A fastener driving apparatus comprises at least one gas spring or spring, a drive mechanism, an anvil assembly, and an anvil. The drive mechanism selectively engages one of the at least one gas spring, spring or anvil assembly. A locking mechanism (such as a one-way clutch) is used to provide a middle stopping point during which the gas spring(s) is/are being energized. The motor of the apparatus may thereafter be turned off. When the user is ready to fire a nail, the motor is re-energized and the drive mechanism continues, releasing the gas spring(s) to drive the nail. The drive mechanism may include its own one-way clutch for overrunning and causing the drive mechanism to be released from the locking mechanism. To complete, the cycle the crank continues rotation and re-engages the anvil assembly and energizes the gas spring(s).

Claims

1. A fastener driving apparatus, the apparatus comprising a power source, a control circuit, a motor, at least one gas spring, said at least one gas spring comprising a chamber and a piston disposed within said chamber a drive mechanism, said drive mechanism capable of selectively engaging and disengaging said at least one gas spring, said at least one gas spring capable of moving to an energized position upon being engaged by said drive mechanism, said drive mechanism comprising a one-way clutch, an anvil assembly, said anvil assembly comprising an anvil, and at least one cable, said at least one cable operatively coupling said drive mechanism to said anvil assembly, wherein said drive mechanism selectively engages said gas spring to apply a force on said gas spring to move said piston of said at least one gas spring and thereafter disengages from and ceases applying a force on said at least one gas spring, wherein when said drive mechanism engages said at least one gas spring, potential energy is stored by said movement, and after said one-way clutch causes said drive mechanism thereafter to disengage said at least one gas spring, said at least one gas spring releases its potential energy and accelerates said anvil.

2. The fastener driving apparatus of claim 1, wherein said one-way clutch is one of a sprag clutch, an over running clutch, a roller clutch, a wrap spring, a spindle lock or a ratchet.

3. The fastener driving apparatus of claim 1, the apparatus comprising a second one-way clutch, wherein said second one-way clutch is capable of causing a stopping point during which potential energy is being stored in the at least one gas spring, and wherein the one way clutch retains the drive mechanism and energized at least one gas spring at the stopping point after power is removed from the motor.

4. The cable of claim 1, wherein said at least one cable is comprised of one of wire rope, Kevlar rope, carbon fiber rope, chain, plastic or the like.

5. The cable of claim 1, wherein the cable force is redirected by at least one pulley.

6. The fastener driving apparatus of claim 1, wherein the pressure in said piston of said at least one gas spring before the drive mechanism actuates said at least one gas spring is at least 40 psia.

7. The fastener driving apparatus of claim 1, wherein the pressure increase in said piston of said at least one gas spring during actuation of the at least one gas spring by the drive mechanism is less than 30% of the pressure in said piston is actuated by the drive mechanism.

8. The fastener driving apparatus of claim 1, the apparatus further comprising at least one sensor for determining at least one position of the drive mechanism, the at least one gas spring, the drive mechanism, the anvil, and the anvil assembly.

9. A fastener driving apparatus, the apparatus comprising a power source, a control circuit, a motor, at least one gas spring, said at least one gas spring comprising a chamber and a piston disposed within said chamber, an anvil assembly, said anvil assembly comprising an anvil and the piston, a drive mechanism capable of selectively engaging and disengaging said gas spring, said gas spring capable of moving to an energized position, upon being engaged by said drive mechanism, said drive mechanism comprising a crank and an overrunning clutch, and at least one cable, said at least one cable operatively coupling said crank to said anvil assembly, wherein said drive mechanism comprises an engagement region for engaging and causing said at least one gas spring to move said piston of said gas spring chamber and a non-engagement region for causing said drive mechanism to cease causing said at least one gas spring to so move, said drive mechanism is connected to said crank by said overrunning clutch, wherein potential energy is stored by said movement of said piston, and after said crank passes bottom dead center said overrunning clutch overruns, thereafter disengaging said at least one gas spring, said at least one gas spring thereby accelerating said anvil assembly.

10. The fastener driving apparatus of claim 9, the apparatus comprising a second one-way clutch, wherein said second one-way clutch is capable of causing a stopping point during which potential energy is being stored in the at least one gas spring, and wherein the one way clutch retains the drive mechanism and energized at least one gas spring at the stopping point after power is removed from the motor.

11. The cable of claim 9, wherein said at least one cable is comprised of one of wire rope, Kevlar rope, carbon fiber rope, chain, plastic or the like.

12. The fastener driving apparatus of claim 9, wherein the pressure in said piston of said at least one gas spring before the drive mechanism actuates said at least one gas spring is at least 40 psia.

13. The fastener driving apparatus of claim 9, wherein the pressure increase in said piston of said at least one gas spring during actuation of the at least one gas spring by the drive mechanism is less than 30% of the pressure in said piston is actuated by the drive mechanism.

14. The fastener driving apparatus of claim 9, the apparatus further comprising at least one sensor for determining at least one position of the crank, the at least one gas spring, the drive mechanism, the anvil, and the anvil assembly.

Description

DESCRIPTION OF THE DRAWINGS

(1) The advantages and features of the present disclosure will become better understood with reference to the following detailed description and claims taken in conjunction with the accompanying drawings, in which like reference numerals refer to like parts throughout the description of several views of the drawings, and in which

(2) FIG. 1 shows a perspective view of a fastener driving apparatus, in accordance with an exemplary embodiment of the present disclosure;

(3) FIG. 2 shows components of a fastener driving apparatus, in accordance with an exemplary embodiment of the present disclosure;

(4) FIG. 3 shows a pulley and cable arrangement of a fastener driving apparatus, in accordance with an exemplary embodiment of the present disclosure;

(5) FIG. 4 shows an anvil assembly of a fastener driving apparatus, in accordance with an exemplary embodiment of the present disclosure;

(6) FIG. 5 shows a one-way clutch of a fastener driving apparatus, in accordance with an exemplary embodiment of the present disclosure; and

(7) FIG. 6 shows a fastener driving apparatus in an energized position, in accordance with an exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

(8) The best mode for carrying out the present disclosure is presented in terms of its preferred embodiment, herein depicted in the accompanying figures. The preferred embodiments described herein detail for illustrative purposes are subject to many variations. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but are intended to cover the application or implementation without departing from the spirit or scope of the present disclosure. Furthermore, although the following relates substantially to one embodiment of the design, it will be understood by those familiar with the art that changes to materials, part descriptions and geometries can be made without departing from the spirit of the disclosure. It is further understood that references such as front, back or top dead center, bottom dead center do not refer to exact positions but approximate positions as understood in the context of the geometry in the attached figures.

(9) The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items.

(10) Referring also to the figures and FIG. 1 in particular, the present disclosure provides for a fastener driving apparatus 100. In an embodiment, and as shown in FIG. 2, for example, the apparatus 100 comprises a power source 10, a control circuit 20, a motor 30, at least one spring 40, a drive mechanism 50 with a crank 52, at least one one-way clutch 57, an anvil assembly 60 (as shown in FIG. 4 in an exemplary embodiment) including a piston 42, and an anvil 62. The apparatus 100 may further comprise at least one cable 55, as shown in FIGS. 2 and 3, or example. The at least one cable connects the crank 52 via pulleys 65 to the anvil assembly 60. In a preferred embodiment two cables are connected to the crank 52 on one end and then connected to either sides of the anvil assembly 60 on the other end. Pulleys 65 are used to direct the cables and allow for optimal placement of the crank 52 and drive mechanism 50.

(11) The apparatus 100 may further comprise at least one bumper 70. The at least one bumper may be disposed within a gas spring and/or outside of a gas spring. The gas spring(s) 40 include a piston 42, which piston 42 is at least partially disposed within a sealed chamber 44, and which piston 42 is selectively actuated by the drive mechanism 50. The gas spring(s) 40 further comprise(s) a nose portion 46 (which nose portion may be a part of or coupled to the piston) and which nose portion 46 extends out of the chamber and which is connected to the anvil 62 and/or anvil assembly 60 during the operational cycle of the apparatus 100.

(12) the drive mechanism 50 may comprise, in an embodiment (and shown in FIG. 5), at least one one-way clutch 57, and, in an embodiment, a series of one-way clutches, and a crank 52 connected to cables 55. It will be apparent that the drive mechanism 50 is configured to energize the gas spring 40 during the downward rotation of the crank 52 (as depicted in FIG. 2) and to release the gas spring 40 via a one-way clutch 57, to drive a fastener on the upward rotation of the crank 52. The drive mechanism 50 is operatively coupled to the anvil or anvil assembly 60 (which anvil assembly comprises the anvil 62 and the piston 42), or, in an particular embodiment, coupled to the piston 42 such that the drive mechanism 50 may alternate in actuating the piston 42 (during the crank downward rotation, for example, and as shown in FIGS. 2 and 3) and in refraining from applying a drive force on the piston. A second one-way clutch may be configured within the drive mechanism to allow the drive mechanism 50 to stop and retain the energized gas spring(s) prior to releasing the anvil assembly 60. In an embodiment, the one-way clutch may be a sprag clutch, an over running clutch, a roller clutch, a wrap spring, a spindle lock and a ratchet. It will be apparent that other devices for stopping and retaining the drive mechanism may be provided, such as a wrap spring or ratchet and pall arrangement. In a preferred embodiment, the drive mechanism 50 preferably acts directly upon the anvil assembly 60 through cables 55 to move the piston 42 to store potential energy (as described elsewhere herein.) Note that the cables 55 can be constructed of wire rope, Kevlar rope, carbon fiber rope, nylon, chain, and the like.

(13) The apparatus may further comprise a means for balancing the forces on the cables when two or more cables are used. By using two stops and a slider connected to the cables the forces can be balanced during the entire rotation of the crank 52.

(14) In an embodiment, the drive mechanism 50 engages and actuates the piston(s) 42 (and/or anvil assembly 60) to store potential energy within the gas spring(s) 40, which actuation of the piston(s) 42 may be referred to as an “energized position” of the piston(s) 42. An exemplary embodiment of such energized position is shown in FIG. 6.

(15) In an embodiment, the initial pressure (before the drive mechanism 50 actuates the piston 42) within the gas spring 40 is at least 40 psia. The configuration and design of the gas spring 40 are such that the pressure increase during the piston movement is less than 30% of the initial pressure, and in an embodiment, less than 25% of the initial pressure, which allows the drive mechanism 50 to operate at a more constant torque, thus improving the motor efficiency. The gas spring(s) of the present disclosure comprise a rod and seal on said rod. Due to at least the rod seal configuration, the apparatus is able to achieve pressure within the gas spring or springs above 200 psi, which provides for more effective driving than the prior art nailers and fastener drivers. Furthermore, the rod seal configuration eliminates the need for a separate chamber that would otherwise enclose the gas spring(s) to achieve such low or small change in pressure during piston movement.

(16) In exemplary embodiment of an operational cycle, the drive mechanism 50 thereafter disengages the piston(s) 42 (and/or anvil assembly 60), allowing potential energy to act on the piston(s) 42 and cause the piston(s) 42 to move and act on the anvil 62 and/or anvil assembly 60 (as will be described in further detail below). The drive mechanism 50 may thereafter again act on the piston(s) 42 (and/or anvil assembly 60) to again store potential energy within the gas spring(s) 40 and may thereafter again temporarily cease to act on the piston(s) 42 (and/or anvil assembly 60) to allow potential energy to instead act on the piston(s) 42.

(17) The anvil 62 and/or anvil assembly 60 is operatively coupled to the gas spring(s) 40, such as to the piston(s) 42 or nose portion(s) such that when the piston(s) 42 is/are released under pressure from the drive mechanism 50, the force from the piston(s) 42 is imparted onto the anvil 62, causing the anvil 62 to move in a direction and to drive a fastener, for example. The anvil 62 may be operatively coupled to a guide, shaft, or other structure that limits and guides the range of motion of the anvil 62. To counteract cam loads or other drive mechanism loads on the anvil and/or anvil assembly, bearings (and preferably, roller bearings) may be provided in the guide, shaft, or other structure that limits the range of motion.

(18) A sensor 90 may be provided for determining at least one position of the crank, gas spring(s), drive mechanism, anvil and/or anvil assembly. The sensor may enable the proper timing for stopping the operational cycle of the apparatus. Further, this information can be used to detect a jam condition for proper recovery.

(19) At least one bumper 70 may optionally be disposed on the apparatus 100 for absorbing a portion of the force of impact of the anvil 62 and/or anvil assembly 60, to reduce wear and tear on the components of the apparatus 100. The at least one bumper 70 may be of an elastic material, for example, and may be disposed on the apparatus 100 at any position where it is capable of absorbing a portion of the force of impact by the piston(s) 42 or the anvil 62. The at least one bumper may be disposed within or outside of a gas spring(s).

(20) A second one-way clutch 58 (shown in FIG. 5, for example) is preferably incorporated into the drive mechanism in order to retain the gas spring(s) in an energized state, although it will be apparent that alternative means of retaining the gas spring or springs in an energized state are possible. This energized state can become the start and stop position for the operational cycle of the apparatus, enabling a much shorter time to fire from cycle start to the driving of a nail. The second one-way clutch 58, will allow the crank to be driven in one direction only. As the crank acts on the anvil assembly, it energizes the gas spring(s). When the motor is thereafter turned off, the second one-way clutch 58 prevents the crank 52 from back driving and keeps the gas spring(s) energized. When the user is ready to fire a nail, the motor is re-energized and the crank continues rotation, releasing the gas spring(s) to drive the nail. To complete, the cycle the crank continues rotation and re-engages the anvil assembly and energizes the gas spring(s). The motor is then turned off and the second one way clutch 58 retains the gas spring(s) in an energized state and ready for the next cycle.

(21) In an embodiment, a sensor 90 may be provided for determining at least one of the position of the crank and/or the anvil and/or anvil assembly upon the anvil to determine whether the anvil and/or anvil assembly is in a state or position to begin another operational cycle or another step of the operational cycle.

(22) In another embodiment of a fastener driving apparatus, safety is enhanced by requiring that a brushless motor be used in conjunction with an anti-reversing mechanism and an intermediate stopping point. This forces the power to connect to the motor to finish the stroke. So although the fastening device would be in a ready or near ready to release position, it would be nearly impossible for the device to release without actuating the motor.

(23) The present disclosure offers the following advantages: the gas springs, mechanical springs and elastomers are capable of generating a relatively high amount of force in a small amount of space such that the size of the apparatus may be smaller than other fastener drivers. Further, because of the relatively small increase from the initial pressure in the gas spring to the maximum pressure, the motor of the apparatus is not significantly overworked or over torqued, thus leading to a longer useful life of the apparatus.

(24) The foregoing descriptions of specific embodiments of the present disclosure have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiment was chosen and described in order to best explain the principles of the present disclosure and its practical application, to thereby enable others skilled in the art to best utilize the disclosure and various embodiments with various modifications as are suited to the particular use contemplated.