Gas spring powered fastener driver with pressure mechanism

Abstract

A gas spring powered fastener driver includes: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver vane attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver vane defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; a cushion positioned under the piston in a vertical direction to absorb impact energy from the piston; and a valve positioned in the reservoir cylinder. In response to the piston compressing the cushion while absorbing impact energy from the piston, the valve adds pressurized air from the cylinder to the reservoir cylinder.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 332,480 filed on April 19, 2022, U.S. Provisional Patent Application No. 63 / 237,494 filed on August 26, 2021, and U.S. Provisional Patent Application No. 63 / 222,606 filed on July 16, 2021, all of which are incorporated herein by reference in their entirety. Technical Field

[0003] The utility model relates to a power fastener driver, and more particularly to a gas spring power fastener driver.

[0004] Utility Model Background

[0005] Various fastener drivers are known in the art for driving fasteners (e.g., nails, tacks, staples, etc.) into a workpiece. These fastener drivers utilize various means known in the art (e.g., compressed air generated by an air compressor, electrical energy, flywheel mechanisms, etc.), but these designs typically encounter power, size, and cost limitations. One factor that existing fastener drivers do not take into account is pressure loss during the life of the tool and / or pressure fluctuations based on external temperature. While an onboard air compressor can help mitigate pressure loss, a typical air compressor (e.g., a reciprocating, axial, screw, or centrifugal compressor) significantly increases the complexity, cost, and weight of the tool and is therefore an unsuitable option. Utility Model Content

[0006] In one aspect, the present invention provides a gas spring powered fastener driver comprising: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; a buffer positioned vertically below the piston to absorb impact energy from the piston; and a valve positioned in the reservoir cylinder. In response to the piston compressing the buffer while absorbing impact energy from the piston, the valve adds pressurized air from the cylinder to the reservoir cylinder.

[0007] In another aspect, the present invention provides a gas spring powered fastener driver comprising: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable therewith between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; a buffer positioned vertically below the piston to absorb impact energy from the piston; and a valve positioned within the reservoir cylinder. The valve opens when pressure within the reservoir cylinder reaches a predetermined level.

[0008] In another aspect, the present invention provides a gas spring powered fastener driver comprising: an air cylinder; a reservoir cylinder having pressurized air in communication with the air cylinder; a movable piston positioned within the air cylinder; a driver blade attached to the piston and movable therewith between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; and a valve positioned between the air cylinder and the reservoir cylinder. The valve is a two-way valve that allows air to flow from the air cylinder to the reservoir cylinder and vice versa.

[0009] In another aspect, the present invention provides a gas spring powered fastener driver comprising: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable therewith between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; and a glow plug positioned within the reservoir cylinder. The glow plug heats the air within the reservoir cylinder when a pressure of the air within the reservoir cylinder is below a predetermined level.

[0010] In another aspect, the present invention provides a gas spring powered fastener driver comprising: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable therewith between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; and a tank divider positioned within the reservoir cylinder. The tank divider moves in response to the pressure of the air within the reservoir cylinder reaching a predetermined level. When the tank divider moves, the volume of the cylinder increases or decreases.

[0011] In another aspect, the present invention provides a gas spring powered fastener driver comprising: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable therewith between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; and an auxiliary tank fluidly coupled to the reservoir cylinder and comprising a valve that opens in response to the pressure of the air within the reservoir cylinder reaching a predetermined pressure.

[0012] In another aspect, the present invention provides a gas spring powered fastener driver comprising: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable therewith between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; and a pressure regulator fluidly coupled to the reservoir cylinder and including an adjustable portion. When the adjustable portion is adjusted, the volume of the reservoir cylinder changes.

[0013] In another aspect, the present invention provides a gas spring powered fastener driver comprising: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable therewith between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; and a pressure regulating system. The pressure regulating system comprises a first check valve positioned on a wall of the cylinder, a second check valve positioned on a wall of the cylinder, and a third check valve disposed on a wall of the reservoir cylinder.

[0014] In another aspect, the present invention provides a gas spring powered fastener driver comprising: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable therewith between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; and a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position. The lifter rotates 16 to 18 times to move the piston from the bottom dead center position to the top dead center position.

[0015] In another aspect, the present invention provides a gas spring powered fastener driver comprising: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; and a sliding seal disposed between the piston and the cylinder. The sliding seal is configured to prevent pressurized air from passing through an annular space between the piston and the cylinder.

[0016] In another aspect, the present invention provides a gas spring powered fastener driver comprising: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable therewith between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; and a pressure relief valve disposed between the cylinder and the reservoir cylinder. The pressure relief valve is adjustable from a closed state to an open state in response to a pressure of air within the cylinder reaching a predetermined pressure, and wherein the pressure relief valve, when in the open state, transmits air from the cylinder to the reservoir cylinder.

[0017] In another aspect, the present invention provides a gas spring powered fastener driver comprising: a cylinder; a reservoir cylinder having pressurized air in communication with the cylinder; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable therewith between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter being configured to engage the driver blade when moving the driver blade from the bottom dead center position toward the top dead center position; and a pump driven by the lifter to discharge pressurized air into the reservoir cylinder. The pump comprises: a pump piston driven by the lifter to reciprocate within a pump chamber, and a valve selectively fluidly coupling the pump chamber to the reservoir cylinder to discharge pressurized air within the pump chamber into the reservoir cylinder.

[0018] Other features and aspects of the invention will become apparent by consideration of the following detailed description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a three-dimensional view of a gas spring powered fastener driver according to an embodiment of the present utility model.

[0020] Figure 2 It is along Figure 1 A partial cross-sectional view of the gas spring powered fastener driver taken along line 2-2 in FIG.

[0021] Figure 3 It is along Figure 1 The line 3-3 in the Figure 1 A cross-sectional view of a gas spring powered fastener driver showing the motor and transmission used to provide torque to the lifter.

[0022] Figure 4 An enlarged cross-sectional view of a portion of a fastener driver illustrating the passages within the fastener driver for replenishing pressure.

[0023] Figure 5 is similar to Figure 4 An enlarged cross-sectional view of a portion of a fastener driver is shown, illustrating a check valve positioned in the passage.

[0024] Figure 6A yes Figure 1 Schematic diagram of a gas spring powered fastener driver showing the driver blade in the driven or bottom dead center position.

[0025] Figure 6B yes Figure 1 Schematic diagram of a gas spring powered fastener driver showing the driver blade in the top dead center position prior to actuation.

[0026] Figure 7 is a schematic diagram of an exemplary pressure relief in a fastener driver.

[0027] Figure 8 is an enlarged cross-sectional view of a portion of a fastener driver illustrating the combined pressure increase and pressure relief mechanism in a first state.

[0028] Figure 9 Another enlarged cross-sectional view of a portion of the fastener driver illustrating the combined pressure increase and pressure relief mechanism in a second state.

[0029] Figure 10 is a cross-sectional view of the combined pressure increase and pressure relief mechanism in a second state.

[0030] Figure 11 is a cross-sectional view of the combined pressure increase and pressure relief mechanism in a first state.

[0031] Figure 12 is a schematic diagram of a portion of a fastener driver including an exemplary glow plug that may be positioned in an external reservoir cylinder and in an operational state to address low operating temperature issues.

[0032] Figure 13 yes Figure 12 Schematic diagram of a fastener driver including a portion of a glow plug that is in a non-operating state due to normal or high operating temperature.

[0033] Figure 14 yes Figure 12 Cross-sectional view of a glow plug.

[0034] Figure 15is a schematic diagram of a portion of a fastener driver including an exemplary can divider showing the driver blade in a top dead center position with the can divider in a neutral position.

[0035] Figure 16 yes Figure 15 Schematic diagram of a tank divider showing the driver blade in a bottom dead center position, wherein the tank divider is in a neutral position at a first operating temperature.

[0036] Figure 17 yes Figure 15 Schematic diagram of a tank divider showing the driver blade in a bottom dead center position, wherein the tank divider is in a neutral position at a second operating temperature.

[0037] Figure 18 yes Figure 15 Schematic diagram of a tank divider showing the actuator blades in the top dead center position with the tank divider in the compressed position.

[0038] Figure 19A is a schematic diagram of another exemplary tank divider for a fastener driver.

[0039] Figure 19B is a schematic diagram of another exemplary tank divider for a fastener driver.

[0040] Figure 20 is a schematic diagram of an exemplary bladder coupled to an external reservoir of a fastener driver, showing the bladder in a neutral position.

[0041] Figure 21 yes Figure 20 Schematic diagram of a bladder showing the bladder in an expanded position.

[0042] Figure 22 is a schematic diagram of an exemplary auxiliary tank coupled to an external storage chamber of a fastener driver, showing the valve of the auxiliary tank in a closed position.

[0043] Figure 23 yes Figure 22 Schematic diagram of the auxiliary tank, showing the auxiliary tank valve in the open position.

[0044] Figure 24 is a schematic diagram of an exemplary manual pressure regulator coupled to an external reservoir of a fastener driver.

[0045] Figure 25 is a schematic diagram of another example manual pressure regulator coupled to an external reservoir of a fastener driver, illustrating the manual pressure regulator in a first or pressurized position.

[0046] Figure 26 yes Figure 25 Schematic diagram of a manual pressure regulator showing the manual pressure regulator in the neutral position.

[0047] Figure 27 yes Figure 25 Schematic diagram of a manual pressure regulator showing the manual pressure regulator in the second or pressure reducing position.

[0048] Figure 28 is a schematic diagram of a portion of a fastener driver including an exemplary pump in the fastener driver, showing the pump in an extended or cocked position.

[0049] Figure 29 yes Figure 28 Schematic diagram of an exemplary pump showing the pump in a retracted or pumping position.

[0050] Figure 30 is a schematic diagram of a portion of a fastener driver including an exemplary driver blade that can be retracted different distances into the fastener driver.

[0051] Figure 31 is a schematic diagram of a portion of a fastener driver including an exemplary pressure control valve.

[0052] Figure 32 is a schematic diagram of a portion of a fastener driver including an exemplary sealing member.

[0053] Figure 33 yes Figure 32 Schematic diagram of the sealing component.

[0054] Figure 34 is a schematic diagram of a sealing component of a fastener driver.

[0055] Figure 35 is a perspective view of another exemplary cylinder.

[0056] Figure 36 yes Figure 35 A cross-sectional view of a cylinder showing the sealing member.

[0057] Figure 37 is a perspective view of another exemplary cylinder.

[0058] Figure 38 yes Figure 37 A cross-sectional view of a cylinder showing the sealing member.

[0059] Figure 39 is a perspective view of another exemplary cylinder.

[0060] Figure 40 yes Figure 39A cross-sectional view of a cylinder showing the sealing member.

[0061] Figure 41 is a perspective view of another exemplary cylinder.

[0062] Figure 42 yes Figure 41 A cross-sectional view of a cylinder showing the sealing member.

[0063] Figure 43 is a perspective view of a portion of another exemplary gas spring powered fastener driver.

[0064] Figure 44 yes Figure 43 A cross-sectional view of a portion of a fastener driver, showing the pressure increasing mechanism.

[0065] Figure 45A yes Figure 43 Schematic diagram of a portion of a fastener driver with the piston of the pressure-boosting mechanism at top dead center.

[0066] Figure 45B yes Figure 43 Schematic diagram of a fastener driver, where the piston is being pushed from top dead center to bottom dead center, causing air to be compressed into the annular space.

[0067] Figure 45C yes Figure 43 Schematic diagram of a fastener driver with the piston having compressed air in the annular space, thereby expelling the compressed air into the reservoir cylinder.

[0068] Figure 45D yes Figure 43 Schematic diagram of a fastener driver, where the piston is being moved from the bottom dead center position toward the top dead center position by a spring.

[0069] Before explaining any embodiments of the present invention in detail, it should be understood that the application of the present invention is not limited to the details of construction and arrangement of components set forth in the following description or illustrated in the following drawings. The present invention is capable of other embodiments and can be practiced or carried out in various ways. Furthermore, it should be understood that the phraseology and terminology used herein are for descriptive purposes only and should not be construed as limiting. DETAILED DESCRIPTION

[0070] refer to Figures 1 to 4 The gas spring powered fastener driver 10 is operable to drive fasteners (e.g., single-head nails, double-head or double-needle nails, tacks, staples, etc.) held within a magazine 14 into a workpiece. The fastener driver 10 includes an inner cylinder 18 and a movable piston 22 ( Figure 5). refer to Figure 5 , the fastener driver 10 further includes a driver blade 26 that is attached to and movable with the piston 22. The fastener driver 10 does not require an external source of air pressure, but rather includes an external reservoir cylinder 30 of pressurized fluid (e.g., gas) that communicates with the cylinder 18. In the illustrated embodiment, the cylinder 18 and the movable piston 22 are positioned within the reservoir cylinder 30.

[0071] refer to Figure 2 、 Figure 4 and Figure 5 , the cylinder 18 and the driver blade 26 define a drive axis 38. Figure 6A and Figure 6B As shown in FIG, during the drive cycle, the driver blade 26 and the piston 22 may be at the top dead center position ( Figure 6B ) and the driving position or bottom dead center position ( Figure 6A ) to move between. Figure 2 The fastener driver 10 is shown to further include a lifter assembly 42 powered by a motor 46 and operable to move the driver blade 26 from the drive position to the top dead center position. The driver 10 also includes a latch assembly 48 that selectively holds the driver blade 26 in the ready position.

[0072] In operation, the lifter assembly 42 drives the piston 22 and the driver blade 26 toward the top dead center position by energizing the motor 46. As the piston 22 and the driver blade 26 are driven toward the top dead center position, the gas above the piston 22 and the gas within the reservoir cylinder 30 are compressed. Before reaching the top dead center position, the motor 46 is deactivated and the piston 22 and the driver blade 26 are held in a ready position between the top dead center position and the bottom dead center position, or the drive position, until they are released by the user activating the trigger 49. When released, the compressed gas above the piston 22 and within the reservoir cylinder 30 drives the piston 22 and the driver blade 26 to the drive position, thereby driving the fastener into the workpiece. The illustrated fastener driver 10 thus operates on the principle of a gas spring, utilizing the lifter assembly 42 and the piston 22 to further compress the gas within the cylinder 18 and the reservoir cylinder 30.

[0073] refer to Figure 2 and Figures 6A to 6B The reservoir cylinder 30 is concentric with the cylinder 18. The cylinder 18 has an annular inner wall 50 that guides the piston 22 and the driver blade 26 along the drive axis 38 to compress the gas in the reservoir cylinder 30. The reservoir cylinder 30 has an annular outer wall 54 that circumferentially surrounds the inner wall 50. The cylinder 18 has a threaded section 58 ( Figure 2). The reservoir cylinder 30 has corresponding threads at the lower end 60 of the reservoir cylinder 30, so that the lower end 60 of the cylinder 18 is threadedly connected to the reservoir cylinder 30. In this way, the cylinder 18 is configured to be axially fixed to the reservoir cylinder 30.

[0074] Reference Figure 1 and Figure 3 , the actuator 10 includes a housing 64 having a cylinder support portion 68 in which the reservoir cylinder 30 is at least partially positioned, and a motor support portion 72 in which the motor 46 and the transmission 80 are at least partially positioned. In the illustrated embodiment, the cylinder support portion 68 is integrally formed as a single unit with the motor support portion 72 (e.g., using a casting or molding process, depending on the materials used). The transmission 80 raises the actuator blade 26 from the drive position to the ready position. Figure 3 The motor 46 is positioned within the transmission housing portion 72 to provide torque to the transmission 80 when activated. Figure 1 ) may be electrically connected to the motor 46 for supplying electrical power to the motor 46. In some embodiments, the drive may be powered by an alternative power source, such as an AC voltage input (i.e., from a wall outlet), or by an alternative DC voltage input (e.g., an AC / DC converter).

[0075] refer to Figure 3 , the transmission 80 includes an input 84 (i.e., the motor output shaft) and includes an output shaft 96 of a lifter 92 extending to the lifter assembly 42, which is operable to move the driver blade 26 from the drive position to the ready position, as explained in more detail below. In other words, the transmission 80 provides torque from the motor 46 to the lifter 92. The transmission 80 shown is coupled to a transmission housing 100. The transmission assembly 80 can take a variety of forms, which will not be described in detail here. For example, the transmission assembly 80 can be the same as or similar to that described in U.S. application serial number 16 / 706,365 (entitled "Gas Spring-Powered Fastener Driver"), the contents of which are incorporated by reference in their entirety. Reference Figure 2 The actuator 10 further includes a lifter housing portion 106 ( Figure 2 ). The lifter housing portion 106 generally encloses the lifter assembly 42, which lifts the driver blade 26 to the ready position.

[0076] refer to Figure 2 , the fastener driver 10 includes a buffer 112 positioned below the piston 22 to stop the piston 22 in the driving position ( Figure 6A) and absorbs the impact energy from the piston 22. The damper 112 is configured to evenly distribute the impact force of the piston 22 across the damper 112 when the piston 22 rapidly decelerates upon reaching the actuated position (i.e., bottom dead center position). The damper 112 is disposed within the cylinder 18 and is clamped in place by the lifter housing portion 106 that is screwed into the bottom end of the cylinder 18. As shown, the damper 112 is received within a cutout 114 formed in the lifter housing portion 106. The cutout 114 aligns the damper 112 coaxially with respect to the driver blade 26.

[0077] In one example, and with reference to Figure 4 and Figure 5 Fastener driver 10 includes a check valve 116 (or similar valve) positioned between buffer 112 and the external reservoir cylinder 30 within passage 118. Check valve 116 responds to pressure as piston 22 compresses buffer 112. More specifically, as piston 22 is driven from the ready position to the driven position, piston 22 strikes buffer 112, which seals inner cylinder 18 to create an air reservoir or annular intermediate chamber 120. When driver blade 26 approaches bottom dead center, intermediate chamber 120 forms between the bottom portion of cylinder 18 and buffer 112 (and, in some cases, between buffer 112 and piston 22). That is, when piston 22 strikes buffer 112, intermediate chamber 120 is completely sealed (i.e., not fluidly connected to the external atmosphere). As piston 22 compresses buffer 112, pressure in intermediate chamber 120 increases and opens check valve 116. This increased air pressure adds a small amount of pressurized air to the external reservoir cylinder 30 through the open check valve 116, which causes a greater pressure to be applied to the cylinder 18, which can compensate for potential or actual air pressure losses in the driver 10. In this way, the compression of the buffer that occurs at the end of each firing event of the driver 10 can be used to generate the increase in air pressure. This avoids the need to attach a separate compressor to the cylinder 30 in order to increase the pressure on the piston 22. In effect, the additional compression of the buffer 112 and the opening of the check valve 116 form an onboard air compressor for the fastener driver 10.

[0078] By repeatedly compressing the buffer 112 with the piston 22 to replenish the pressure in the reservoir cylinder 30, a small amount of air pressure (e.g., approximately 0.01 psi-0.015 psi) can be added each time the buffer 112 is compressed by the piston 22. Extrapolating over 1,000 nails fired by the driver 10, this added pressure is approximately equal to 10 psi-15 psi, which is 10%-15% of the total tank pressure. Although this added pressure is relatively small compared to the total tank pressure, the added pressure facilitated by the compression of the buffer 112 and the open check valve 116 is sufficient to maintain adequate tank pressure even after accounting for pressure losses (e.g., due to infiltration, small amounts of debris ingress, or minor mechanical wear).

[0079] In some cases, the operating temperature or the ambient temperature associated with the fastener driver 10, or both, may increase the pressure applied to the piston 22 to the point where pressure relief is desired. In these cases, and with reference to Figure 7 , the fastener driver 10 may include a pressure relief valve 124 that opens at a predetermined pressure to vent air when the pressure in the reservoir cylinder 30 is higher than required to properly seat the fastener, while also preventing the fastener driver 10 from absorbing more energy than necessary from the movement of the piston 22. For example, at high temperatures, the pressure on the piston 22 may increase to the point where air is vented via valve 124 to maintain the fastener driver 10 within a desired pressure tolerance. Additionally, at low operating temperatures of the fastener driver 10, the on-load compressor defined by the compression of the buffer 112 and the opening of the check valve 116 (i.e., utilizing the air reservoir formed by the buffer 112 when it seals the cylinder 18) helps repressurize the cylinder 18 to maintain the performance of the fastener driver 10.

[0080] It should be understood that some embodiments of the fastener driver 10 may include, in combination, a check valve 116 for increasing pressure within the reservoir cylinder 30 and a pressure relief valve 124 for releasing pressure from the reservoir cylinder 30 .

[0081] In another example, and referring to Figures 8 to 11, the fastener driver 10 may include a combination valve 128 positioned between the buffer 112 and the reservoir cylinder 30, such as in the passage 118, which combines the functions of a check valve and a pressure relief valve. The exemplary combination valve 128 is manufactured by Minivalve, Inc., located at 692 Oak Tree Boulevard, Suite 200, Cleveland, OH 44131. In this example, the valve 128 is responsive to the pressure when the piston 22 compresses the buffer 112, and is responsive to the pressure in the reservoir cylinder 30 such that the valve 128 can increase the pressure in the reservoir cylinder 30 when the pressure is below a desired amount. The valve 128 can also reduce or relieve the pressure when the pressure in the reservoir cylinder 30 is above the desired pressure of the piston 22. Figure 10 and Figure 11 As shown in FIG, valve 128 includes a pressure relief valve 132 and a membrane 136 having a hole or opening 140 to which or within which the pressure relief valve 132 is coupled. The pressure relief valve 132 includes a body defining a tapered passage 144 and having an annular shoulder 148 and an annular flange 152. The tapered passage 144 narrows from the side of the pressure relief valve 132 that communicates with the air reservoir 120 toward the reservoir cylinder 30. The shoulder 148 engages the membrane 136 on a first side within the reservoir cylinder 30 to hold the pressure relief valve 132 in place. The flange 152 engages the membrane 136 on a second side, opposite the first side, and is responsive to pressure within the reservoir cylinder 30 to release pressure within the reservoir cylinder 30 when the pressure exceeds a predetermined amount.

[0082] The membrane 136 also includes an orifice or opening 156 that facilitates pressure relief. The opening 156 is aligned with the flange 152, as shown in FIG. Figure 10 , so that when the pressure in the storage chamber cylinder 30 is above a predetermined threshold, the excess pressure causes the flange 152 to flip or turn over to release the excess pressure. After the pressure is released, the flange 152 can be designed to return to the state shown. The pressure relief valve 132 and the membrane 136 also help to increase the pressure in the storage chamber cylinder 30. In particular, and with reference to Figure 11 When the piston 22 impacts the bumper 112 and generates additional air pressure within the air reservoir 120, the additional high-pressure air is directed through the tapered passage 144 into the reservoir cylinder 30 to replenish the pressure in the reservoir cylinder 30. The tapered passage 144 helps provide airflow communication from the air reservoir 120 to the reservoir cylinder 30 when it is necessary to replenish the pressure in the reservoir cylinder 30, while also ensuring that pressure is released through the opening 156 when the pressure in the reservoir cylinder 30 is higher than desired (e.g., due to operating temperature, ambient temperature, or both).

[0083] In another example, and with reference to Figures 12 to 14 , the fastener driver 10 includes a glow plug 200 positioned within the reservoir cylinder 30. Figure 12 and Figure 14 As shown in FIG, the glow plug 200 includes a sensor 202 that measures the pressure within the reservoir cylinder 30 and a heating rod 204 that selectively heats the air within the reservoir cylinder 30. The sensor 202 may be a piezoresistive strain gauge pressure sensor or another sensor that can measure pressure. The glow plug 200 heats the air within the reservoir cylinder 30 via the heating rod 204 based on the pressure measured by the sensor 202.

[0084] In use, when the pressure within the reservoir cylinder 30 drops below a predetermined level, the glow plug 200 may be used to heat the air within the reservoir cylinder 30. For example, the pressure within the reservoir cylinder 30 may drop due to a lower ambient temperature in the external environment. When the sensor 202 detects that the pressure has dropped below a predetermined level, the glow plug 200 may be activated to heat the air within the reservoir cylinder 30 and increase the pressure within the reservoir cylinder 30 ( Figure 12 ). refer to Figure 13 When the sensor 202 determines that the pressure in the reservoir cylinder 30 is above a predetermined level (e.g., due to an increase in temperature caused by firing the fastener driver 10 or due to an increase in the external ambient temperature), the glow plug 200 turns off (or is turned off). In other words, when the pressure in the reservoir cylinder 30 is low, the glow plug 200 is used only to heat the air in the reservoir cylinder 30. The reservoir cylinder 30 can have an initial fill pressure lower than that typically used because the glow plug 200 can be implemented to increase the pressure. For example, the reservoir cylinder 30 can be filled to approximately 80% of a typical initial fill pressure. The glow plug 200 regulates the pressure in the reservoir cylinder 30 so that the pressure remains within a desired range regardless of the firing rate of the fastener driver 10 or the external ambient temperature.

[0085] In another example, and with reference to Figures 15 to 18 , the fastener driver 10 includes a tank divider 300 disposed in the reservoir cylinder 30 between an outer surface 304 of the cylinder 18 and an inner surface 306 of the reservoir cylinder 30. The illustrated tank divider 300 includes a ring 308 spanning the space between the cylinder 18 and the reservoir cylinder 30, and an O-ring coupled to the ring 308 at the outer surface 304 of the chamber 30. In some embodiments, the ring 308 can be formed of metal. In other embodiments, the ring 308 can be formed of other materials (e.g., plastic, composite materials, etc.). The tank divider 300 is biased toward a top dead center position (i.e., a neutral position of the tank divider 300) by a spring 312.

[0086] As the temperature within the cylinder 18 and the reservoir cylinder 30 increases, the pressure within the cylinder 18 and the reservoir cylinder 30 also increases. For example, and with reference to Figures 15 to 17 , the temperature within the cylinder 18 and the storage chamber cylinder 30 may increase due to the firing of the piston 22. As the piston 22 moves downward, the tank divider 300 remains in the neutral position. Figure 18 It is shown that when the pressure within the air cylinder 18 and the reservoir cylinder 30 reaches a predetermined level due to the added heat, the tank divider 300 is biased toward bottom dead center against the mechanical bias of the spring 312. This movement of the tank divider 300 increases the volume of the reservoir cylinder 30 to regulate the pressure within the reservoir cylinder 30. In other words, as the temperature within the reservoir cylinder 30 increases, the pressure within the reservoir cylinder 30 remains substantially constant (e.g., 164 psi) due to the increase in the volume of the reservoir cylinder 30.

[0087] In some embodiments, the tank divider 300 may take the form of a gas spring coupled to the storage chamber cylinder 30. In one example, and with reference to Figure 19A and Figure 19B , the spring 312 may be located in a compartment 318 that protrudes outward from the reservoir cylinder 30. In some embodiments, the spring 312 may be a mechanical spring ( Figure 19A In other embodiments, the spring 312 may be a gas spring ( Figure 19B ). Compartment 318 is fluidly coupled to the reservoir cylinder 30 via opening 322. Spring 312 biases the tank divider 300 toward the reservoir cylinder 30. When the pressure within the reservoir cylinder 30 increases, the pressure biases the tank divider 300 away from the reservoir cylinder 30, thereby compressing spring 312. The movement of the tank divider 300 increases the volume of the reservoir cylinder 30, which regulates the pressure within the reservoir cylinder 30 to maintain a substantially constant pressure.

[0088] In another example, and with reference to Figure 20 and Figure 21 , the fastener driver 10 includes a bladder 400 fluidly coupled to the reservoir cylinder 30. The bladder 400 may be a rubber bladder, or the bladder 400 may include a metal spring acting on a pressurized bladder portion of the bladder 400. The bladder 400 is coupled to the reservoir cylinder 30 via a conduit 404. In some embodiments, the bladder 400 may be coupled to the reservoir cylinder 30 via other connections. The bladder 400 is moved from a neutral position ( Figure 20 ) changes to the expanded position ( Figure 21) to maintain a substantially constant pressure (e.g., 164 psi) in the reservoir cylinder 30. In the neutral position, the bladder 400 has a first volume, and in the expanded position, the bladder 400 has a second, larger volume. In use, as the temperature within the reservoir cylinder 30 increases, the pressure within the reservoir cylinder 30 also increases. Increased air enters the bladder 400 via the conduit 404, causing the bladder 400 to expand to the expanded position ( Figure 21 The expansion of the bladder 400 increases the volume of the reservoir cylinder 30 to cope with the increase in pressure. The bladder 400 allows air to move in and out of the reservoir cylinder 30 so that the pressure within the reservoir cylinder 30 remains substantially constant regardless of the temperature within the reservoir cylinder 30.

[0089] In another example, and with reference to Figure 22 and Figure 23 , the fastener driver 10 includes an auxiliary tank 500 that is fluidly coupled to the reservoir cylinder 30 via a pressure relief valve 504. The pressure relief valve 504 includes a valve housing 508, a plunger 512 disposed in the valve housing 508, and a spring 516 that biases the plunger 512 toward the auxiliary tank 500. In some embodiments, the pressure relief valve 504 is a one-way valve so that air can only pass from the auxiliary tank 500 to the reservoir cylinder 30. In other embodiments, the pressure relief valve 504 can be a two-way valve. The reservoir cylinder 30 and the auxiliary tank 500 are filled with pressurized air to respective predetermined pressures (e.g., 164 psi and 500 psi, respectively). The respective pressures in the reservoir cylinder 30 and the auxiliary tank 500 can vary. The auxiliary tank 500 is filled to a higher pressure than the reservoir cylinder 30 to accommodate potential pressure drops within the reservoir cylinder 30. When the pressure in the storage chamber cylinder 30 drops (for example, due to a leak or a drop in operating temperature caused by low ambient temperature), the pressure relief valve 504 opens to allow air from the auxiliary tank 500 to re-pressurize the storage chamber cylinder 30. More specifically, the spring 516 and the air in the storage chamber cylinder 30 bias the plunger 512 toward the closed position against the bias of the air in the auxiliary tank 500. When the pressure in the storage chamber cylinder 30 drops, the force acting on the plunger 512 also drops. This drop in force allows the air in the auxiliary tank 504 to bias the plunger 512 to the open position, thereby allowing air from the auxiliary tank 504 to enter the storage chamber cylinder 30, thereby re-pressurizing the storage chamber cylinder 30. The pressure relief valve 504 can re-pressurize the storage chamber cylinder 30 to a minimum pressure. In some embodiments, the minimum pressure can be approximately 140 psi. In other embodiments, the minimum pressure can be higher or lower than 140 psi.

[0090] In another example, and with reference to Figure 24, the fastener driver 10 includes a manual pressure regulator 600 located at the end of the reservoir cylinder 30. In other embodiments, the location of the manual pressure regulator 600 can be different. The manual pressure regulator 600 has an adjustable portion 604 that is coupled to the reservoir cylinder 30 (e.g., by a threaded connection). A user can engage the adjustable portion 604 to change the position of the regulator 600 relative to the reservoir cylinder 30. Changing the position of the adjustable portion 604 changes the volume of the reservoir cylinder 30 so that the pressure within the reservoir cylinder 30 can be set to or maintained at a desired level (e.g., 164 psi). For example, rotating or otherwise moving the adjustable portion 604 by a small amount slightly changes the volume of the reservoir cylinder 30 (and therefore changes the pressure therein), while rotating or moving the adjustable portion 604 by a relatively large amount changes the volume of the reservoir cylinder 30 (and therefore changes the pressure therein) by a correspondingly large amount. The regulator 600 can be used to maintain the pressure within the reservoir cylinder 30 substantially constant, or to restore pressure that has been lost. For example, the regulator 600 can be adjusted by rotating the adjustable portion 604 outward ( Figure 24 The adjustable portion 604 is rotated (upward) to increase the volume within the reservoir cylinder 30 to cope with higher temperatures which increase the pressure within the reservoir cylinder 30. The temperature affecting the pressure within the reservoir cylinder 30 may be high due to firing the fastener driver 10 or high ambient temperature.

[0091] The regulator 600 may take different forms. For example, and with reference to Figures 25 to 27 , the regulator 600 can be movable between a plurality of predetermined positions. For example, the adjustable portion 604 can be in a neutral position ( Figure 26 ), first or pressurized position ( Figure 25 ), and a second or reduced pressure position ( Figure 27 ) are movable between. In other embodiments, the adjustable portion 604 may be movable between more than three positions or fewer than three positions. Each of the first position and the second position changes the volume of the reservoir cylinder 30 relative to the neutral position. For example, the second position increases the volume of the reservoir cylinder 30 ( Figure 27 ), while the first position reduces the volume of the storage chamber cylinder 30 ( Figure 25 The neutral position maintains the volume of the storage chamber cylinder 30 ( Figure 26 The adjuster 600 may include one or more stops 608 that interact with corresponding protrusions 612 in the reservoir cylinder 30 (or vice versa) to hold the adjustable portion 604 in each position, such as Figure 24 In other embodiments, the adjustable portion 604 may be retained to the reservoir cylinder 30 in other ways.

[0092] In use, the user can move the adjustable portion 604 to change the pressure in the reservoir cylinder 30. When the adjustable portion 604 is in the neutral position, the reservoir cylinder 30 is filled with compressed air to a predetermined pressure. When the pressure in the reservoir cylinder 30 is low, the user can move the adjustable portion 604 to the first position ( Figure 25 ), which reduces the volume of the storage chamber cylinder 30 and increases the pressure in the storage chamber cylinder 30. When the pressure in the storage chamber cylinder 30 is high, the user can move the adjustable portion 604 to the second position ( Figure 27 ), which increases the volume of the storage chamber cylinder 30 and reduces the pressure within the storage chamber cylinder 30.

[0093] In some embodiments, the manual pressure regulator 600 may include an indicator 616, such as Figure 1 As shown. Indicator 616 can be positioned on an outer surface of fastener driver 10 so that indicator 616 is visible to the user. Indicator 616 can indicate to the user that moving adjustable portion 604 to the first position seats the fastener deeper in the workpiece, while moving adjustable portion 604 to the second position seats the fastener shallower in the workpiece. The seating of the fastener is affected by the air pressure within reservoir cylinder 30. Indicator 616 can additionally or alternatively indicate to the user that the pressure within reservoir cylinder 30 is within a predetermined range. In some embodiments, a separate indicator can indicate the pressure within reservoir cylinder 30. In other embodiments, indicator 616 can only indicate the seating of the fastener. In other embodiments, indicator 616 can only indicate the pressure within reservoir cylinder 30.

[0094] In another example, and with reference to Figure 28 and Figure 29 , the fastener driver 10 includes a pressure regulation system 700. The pressure regulation system 700 includes a first check valve 702 and a second check valve 704 in a wall 708 of the cylinder 18, below the bumper 112. When opened, the first check valve 702 and the second check valve 704 fluidly couple the cylinder 18 to the reservoir cylinder 30. The pressure regulation system 700 also includes a third check valve 712 disposed on a wall 716 of the reservoir cylinder 30. When opened, the third check valve 712 fluidly couples the reservoir cylinder 30 to the outside atmosphere.

[0095] During use, when the piston 22 strikes the buffer 122, the temperature within the cylinder 18 and the reservoir cylinder 30 increases. This increase in temperature causes the pressure within the cylinder 18 to increase. When the pressure within the cylinder 18 reaches a predetermined level, the first check valve 702 and the second check valve 704 open to allow pressurized air to enter the reservoir cylinder 30. The flow of pressurized air into the reservoir cylinder 30 increases the pressure within the reservoir cylinder 30. When the pressure within the reservoir cylinder 30 increases beyond a predetermined level, the third check valve 712 opens to the external environment to at least partially depressurize the reservoir cylinder 30. In this way, the pressure within the reservoir cylinder 30 is regulated so that the pressure does not exceed the predetermined level. Bleeding air from the reservoir cylinder 30 is advantageous in situations where the fastener driver 10 has a high firing speed, when the external ambient temperature is high, or when both factors are present.

[0096] In another example, and with reference to Figure 30 In one embodiment, the fastener driver 10 includes a driver blade 800 that can be retracted further than existing driver blades to change the pressure in the storage chamber cylinder 30, which affects the piston during subsequent strokes. The increased retraction may require increasing tool height (e.g., approximately 1 inch-2 inches). In this embodiment, the fastener driver 10 includes a lifter 804 that is smaller than the lifter in the lifter assembly 42. Smaller lifters 804 rotate more than larger lifters to allow incremental adjustment of the pressure in the storage chamber cylinder 30. In certain embodiments, lifter 804 has a diameter of approximately 0.15 inches. In certain embodiments, lifter 804 rotates 16 to 18 times to move piston 22 from the bottom dead center position to the top dead center position. By rotating lifter 804 an additional number of revolutions, the distance between top dead center and bottom dead center increases, which allows piston 22 to compress the pressurized air in the storage chamber cylinder 30 to a higher pressure when firing. In this example, the reservoir cylinder 30 may initially be filled to a lower pressure as the piston 22 compresses the air to a higher pressure. For example, in some embodiments, the initial fill pressure of the reservoir cylinder 30 may be 80% of the normal fill pressure.

[0097] Additionally, the driver blade 800 includes a plurality of notches 806 ( Figure 30804 ). These notches interact with the pawl 808 to hold the driver blade 800 in different positions depending on how far the driver blade 800 is lifted by the lifter 804. For example, the driver blade 800 can be held in a low-power position 812 (a first top dead center position), a mid-power position 816 (a second top dead center position), and a high-power position 820 (a third top dead center position). In the illustrated low-power position 812 of the driver blade 800, the lifter 804 rotates 16 times from the bottom dead center position. In the mid-power position 816, the lifter 804 rotates 17 times from the bottom dead center position. In the high-power position 820, the lifter 804 rotates 18 times from the bottom dead center position.

[0098] In another example, and with reference to Figure 31 , the fastener driver 10 includes a valve 900 disposed in the reservoir cylinder 30. The illustrated valve 900 is positioned at the end 904 of the cylinder 18 such that a sleeve 908 extending from the body 912 of the valve 900 engages an outer surface 916 of the cylinder 18. The valve 900 includes a leg 920 that extends from the body 912 of the valve 900 through an end 924 of the reservoir cylinder 30 such that the leg 920 is exposed to the external environment. A spring 928 is positioned about the leg 920 to bias the body 912 toward the cylinder 18. In use, increased pressure within the cylinder 18 pushes the valve 900 toward the end 924 of the reservoir cylinder 30, thereby compressing the spring 928. The valve 900 is in this direction ( Figure 31 Movement of the sleeve 908 (in the center and upward) reduces the air pressure applied to the piston 22 from the reservoir cylinder 30 by reducing the flow rate of air toward the piston 22. As the pressure increases or decreases, the sleeve 908 moves in response to adjust the flow rate of air acting on the piston 22. After the pressure returns to normal, the spring 928 biases the sleeve 908 to a nominal position toward the piston 22. The preload on the spring 928 can be adjusted to vary the power output of the driver blades.

[0099] In another example, and with reference to Figure 32 and Figure 33 , the fastener driver 10 includes a sealing member 1010 disposed between the piston 22 and the cylinder 18. The sealing member 1010 seals the annular space between the piston 22 and the cylinder 18 so that compressed air cannot escape through the annular space. In other words, when the piston 22 moves between the top dead center position and the bottom dead center position, the sealing member 1010 prevents the compressed air from escaping between the piston 22 and the inner wall 1014 of the cylinder 18.

[0100] In this embodiment, a check valve 116 may be included, such as Figure 5As shown in FIG. , check valve 116 responds to pressure as piston 22 moves from top dead center to bottom dead center. More specifically, when piston 22 is driven from the ready position to the driven position, sealing member 1010 prevents compressed air from escaping from intermediate chamber 120. When pressure builds within intermediate chamber 120, check valve 116 opens, allowing compressed air from intermediate chamber 120 to flow into outer reservoir cylinder 30, thereby repressurizing outer reservoir cylinder 30. In other embodiments, fastener driver 10 may not include check valve 116.

[0101] Sealing member 1010 includes a ring 1018 and a wall 1022 integrally formed with ring 1018. Ring 1018 includes a first face 1026 and a second face 1030 parallel to first face 1026. Ring 1018 also includes a circular cutout 1034 located in the center of ring 1018. Wall 1022 extends outward from the edge of ring 1018 such that an inner face 1038 and an outer face 1042 of wall 1022 form obtuse angles relative to first face 1026 and second face 1030 of ring 1018. For example, outer faces 1038 and 1042 may form angles of 95 degrees, 100 degrees, or the like relative to first face 1026 and second face 1030 of ring 1018. In other embodiments, outer faces 1038 and 1042 may form angles of 90 degrees or less relative to first face 1026 and second face 1030 of ring 1018. Wall 1022 is continuous along the edge of ring 1018, so that wall 1022 also forms a circular ring. The edge of wall 1022 is chamfered so that the length or height of inner face 1038 is shorter than the length or height of outer face 1042. When positioned within fastener driver 10, ring 1018 extends inwardly into the space formed in piston 22, and wall 1022 is positioned along surface 1046 of piston 22. Inner face 1038 of wall 1022 contacts surface 1046 of piston 22, while outer face 1042 of wall 1022 contacts inner wall 1014 of cylinder 18. Sealing member 1010 can be formed from a rubber material, silicone material, or the like. Sealing member 1010 functions as a single-acting seal. In other words, sealing member 1010 maintains pressure in only one direction.

[0102] In another example, and with reference to Figure 34 , the sealing member 1010 may include a first arm 1110 and a second arm 1114 extending from the edge of the wall 1022. In other words, the first arm 1110 and the second arm 1114 replace the Figure 331038. The first arm 1110 includes a first face 1118 that is continuous with the interior face 1038. The second arm 1114 includes a second face 1122 that is continuous with the exterior face 1042. The first arm 1110 and the second arm 1114 are angled away from each other such that the first face 1110 is angled relative to the interior face 1038 and the second face 1114 is angled relative to the exterior face 1042. The second arm 1114 defines a length that is greater than the length of the first arm 1110. The second arm 1114 also defines a width that is greater than the width of the first arm 1110. In other embodiments, the length and / or width of the second arm 1114 can be less than or equal to the length and / or width of the first arm 1110. The cross-sectional shape of the arms can be rectangular, circular, elliptical, etc. When positioned within the fastener driver 10 , the first face 1118 of the first arm 1110 contacts the surface 1046 of the piston 22 , while the second face 1122 of the second arm 1114 contacts the inner wall 1014 of the cylinder 18 .

[0103] In another example, and with reference to Figure 35 and Figure 36 The fastener driver 10 includes a pressure release mechanism 1200 disposed between the air cylinder 18 and the reservoir cylinder 30. The air cylinder 18 includes an orifice 1204 extending between the air cylinder 18 and the reservoir cylinder 30, fluidically connecting the air cylinder 18 and the reservoir cylinder 30. The pressure release mechanism 1200 is positioned adjacent to the orifice 1204 to seal the orifice 1204. In other words, the pressure release mechanism 1200 seals the orifice 1204, fluidically separating the air cylinder 18 and the reservoir cylinder 30. In some embodiments, the pressure release mechanism 1200 is a slidable plug 1208, with an O-ring 1212 disposed on the exterior of the slidable plug 1208. A spring 1216 is disposed on one end of the slidable plug 1208, biasing the slidable plug 1208 toward the orifice 1204. When the pressure within the air cylinder 18 reaches a predetermined pressure, the slidable plug 1208 is pushed away from the air cylinder 18, thereby compressing the spring 1216. Movement of the slidable plug 1208 allows air to escape from the cylinder 18 and enter the reservoir cylinder 30 .

[0104] In other embodiments, Figure 37 and Figure 38As shown in , the pressure release mechanism 1200 is an O-ring 1300. The O-ring 1300 is located in an angled groove 1304 on the surface of the cylinder 18, near the orifice 1204. The O-ring 1300 seals the opening 1306 of the orifice 1204 so that fluid cannot leave the opening 1306 of the orifice 1204 without moving the O-ring 1300. The O-ring 1300 is formed of an elastic material so that the O-ring 1300 bends when stretched. When the pressure within the cylinder 18 reaches a predetermined level, the pressure within the cylinder 18 stretches the O-ring 1300 so that air can escape from the cylinder 18 and enter the reservoir cylinder 30. In other embodiments, such as Figure 39 and Figure 40 As shown in FIG, O-ring 1300 can be replaced with a band 1400. Similar to O-ring 1300, band 1400 seals opening 1306 of orifice 1204. Band 1400 is formed from an elastomeric material, making it flexible. In some embodiments, a band clamp 1404 can be positioned on a portion of band 1400 to maintain the position of band 1400 on the surface of cylinder 18. In other embodiments, band clamp 1404 may not be included.

[0105] In other embodiments, Figure 41 and Figure 42 As shown in FIG, the pressure release mechanism 1200 is a U-shaped seal 1500 positioned adjacent the opening 1306 of the orifice 1204, sealing the opening 1306. The U-shaped seal 1500 is formed of an elastic material such that the U-shaped seal 1500 flexes when biased. When the pressure within the cylinder 18 reaches a predetermined level, the pressure within the cylinder 18 causes the U-shaped seal 1500 to flex, causing a portion of the U-shaped seal 1500 to seal against a surface of the cylinder 18 rather than against the opening 1306 of the orifice 1204. In this position, air can escape from the cylinder 18 into the reservoir cylinder 30. When the pressure within the cylinder 18 falls below the predetermined level, the U-shaped seal 1500 reseals the opening 1306 of the orifice 1204.

[0106] In another example, and with reference to Figure 43 and Figure 44, the lifter assembly 42 includes a cam 1600 that engages with the small piston 1604. More specifically, when the piston 22 is in the bottom dead center position, the lifter assembly 42 pushes the cam 1600 to engage with the small piston 1604. When the piston moves from the bottom dead center position to the top dead center position, the lifter assembly 42 disengages the cam 1600 and the small piston 1604. In some embodiments, the cam 1600 can alternatively engage with a feature on the piston 22. The small piston 1604 is positioned in an orifice 1608 in the reservoir cylinder 30 and can slide within the orifice. The cam 1600 is configured to bias the small piston 1604 from the small piston top dead center position to the small piston bottom dead center position, as shown in FIG. Figure 45A In other words, the cam 1600 biases the small piston 1604 toward the storage chamber cylinder 30. When the cam 1600 biases the small piston 1604 from the small top dead center position to the small bottom dead center position, the small piston 1604 compresses the air in the orifice 1608, increasing the pressure in the orifice 1608, as shown in FIG. Figure 45B shown.

[0107] The orifice 1608 includes a check valve 1612 positioned near the bottom dead center position. Once the pressure within the orifice 1608 reaches a predetermined pressure, the check valve 1612 opens, allowing air to enter the reservoir cylinder 30, increasing the pressure within the reservoir cylinder 30. Figure 45C As shown. When the small piston 1604 is at the small bottom dead center position, the lifter assembly 42 releases the small piston 1604. Once the lifter assembly 42 releases the small piston 1604, the spring 1616 on the small piston 1604 biases the small piston 1604 back to the small top dead center position, as shown. Figure 45D As shown in FIG. When small piston 1604 moves to the small top dead center position, a vacuum is created within orifice 1608. A hole 1620 in orifice 1608 allows external air to enter orifice 1608. Thereafter, small piston 1604 is again pushed to the small bottom dead center position by lifter assembly 42, beginning an additional compression cycle. Reservoir cylinder 30 includes a relief valve 1624 that allows air to escape from reservoir cylinder 30 and into the external environment when a predetermined pressure is reached. In other embodiments, reservoir cylinder 30 may not include a relief valve.

[0108] Although the invention has been described in detail with reference to certain preferred embodiments, variations and modifications exist within the scope and spirit of one or more independent aspects of the invention described.

Claims

1. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; a buffer member positioned vertically below the piston to absorb impact energy from the piston; as well as a valve positioned in the reservoir cylinder; wherein the valve adds pressurized air from the cylinder to the reservoir cylinder in response to the piston compressing the buffer while absorbing impact energy from the piston.

2. The gas spring powered fastener driver of claim 1, wherein: The valve is positioned between the cylinder and the reservoir cylinder.

3. The gas spring powered fastener driver of claim 2, wherein: The valve is a two-way valve that allows air to flow from the cylinder to the reservoir cylinder and from the reservoir cylinder to the cylinder.

4. The gas spring powered fastener driver of claim 1, wherein: When the piston strikes the bumper, an air reservoir is created between the cylinder and the bumper, and wherein the air reservoir is fluidly sealed.

5. The gas spring powered fastener driver of claim 4, wherein: When the pressure in the air reservoir increases, the valve opens.

6. The gas spring powered fastener driver of claim 4, wherein: As the piston moves from the top dead center position toward the bottom dead center position, pressure is added to the air reservoir.

7. The gas spring powered fastener driver of claim 1, further comprising a second valve located in the reservoir cylinder, wherein: When the pressure in the storage chamber cylinder reaches a predetermined level, the second valve releases the air in the storage chamber cylinder.

8. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; a buffer member positioned vertically below the piston to absorb impact energy from the piston; as well as a valve positioned in the reservoir cylinder; When the pressure in the storage chamber cylinder reaches a predetermined level, the valve opens.

9. The gas spring powered fastener driver of claim 8, wherein: The valve is positioned at an end of the reservoir cylinder, wherein a sleeve extending from a body of the valve engages an outer surface of the reservoir cylinder.

10. The gas spring powered fastener driver of claim 9, wherein: The valve includes a leg extending from the body through an end of the reservoir cylinder such that the leg is exposed to the external environment.

11. The gas spring powered fastener driver of claim 10, wherein: The valve includes a spring positioned about the leg to bias the body toward the reservoir cylinder.

12. The gas spring powered fastener driver of claim 11, wherein: When the pressure within the reservoir cylinder reaches a predetermined level, the valve is biased toward the end of the reservoir cylinder, thereby compressing the spring.

13. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; as well as a valve positioned between the cylinder and the reservoir cylinder; The valve is a two-way valve that allows air to flow from the cylinder to the reservoir cylinder and from the reservoir cylinder to the cylinder.

14. The gas spring powered fastener driver of claim 13, wherein: The valve includes an annular flange and an opening, and wherein the flange blocks the opening when the pressure in the reservoir cylinder is below a predetermined pressure.

15. The gas spring powered fastener driver of claim 14, wherein: When the pressure in the reservoir cylinder reaches a predetermined pressure, the flange flips over, allowing air to escape from the opening.

16. The gas spring powered fastener driver of claim 13, wherein: The valve includes a tapered passage disposed in a body of the valve, wherein the tapered passage is configured to assist in providing air flow from the cylinder to the reservoir cylinder.

17. The gas spring powered fastener driver of claim 16, wherein: When the piston strikes the bumper, air is directed through the tapered passage into the reservoir cylinder.

18. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; as well as a glow plug positioned within the reservoir cylinder; When the pressure of the air in the cylinder of the storage chamber is lower than a predetermined level, the glow plug heats the air in the cylinder of the storage chamber.

19. The gas spring powered fastener driver of claim 18, wherein: The glow plug includes a sensor that measures pressure within the reservoir cylinder and a heating rod that selectively heats air within the reservoir cylinder.

20. The gas spring powered fastener driver of claim 19, wherein: The sensor is a piezoresistive strain gauge pressure sensor.

21. The gas spring powered fastener driver of claim 19, wherein: The glow plug is turned off when the sensor determines that the pressure in the reservoir cylinder is above the predetermined level, and wherein the glow plug is turned on when the sensor determines that the pressure in the reservoir cylinder is below the predetermined level.

22. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; as well as a tank divider positioned within the storage chamber cylinder; wherein the tank divider moves in response to the pressure of the air in the storage chamber cylinder reaching a predetermined level, and When the tank divider moves, the volume of the cylinder increases or decreases.

23. The gas spring powered fastener driver of claim 22, further comprising a spring biasing the can divider toward a position where the volume of the cylinder is reduced.

24. The gas spring powered fastener driver of claim 23, wherein: The tank divider is disposed in the storage chamber cylinder between an outer surface of the cylinder and an inner surface of the storage chamber cylinder.

25. The gas spring powered fastener driver of claim 24, wherein: The tank divider includes a circular ring, and wherein an O-ring is coupled to the circular ring at an outer surface of the cylinder.

26. The gas spring powered fastener driver of claim 23, further comprising a compartment coupled to an outer surface of the reservoir cylinder, the tank divider being located in the compartment, wherein The compartment is fluidly coupled to the reservoir cylinder to receive pressurized air from the reservoir cylinder.

27. The gas spring powered fastener driver of claim 26, wherein: The spring biases the tank divider toward the reservoir cylinder, and wherein, when pressure within the reservoir cylinder increases, the pressure biases the tank divider away from the reservoir cylinder, thereby compressing the spring.

28. The gas spring powered fastener driver of claim 22, wherein: The tank divider is a metal bladder fluidly coupled to the reservoir cylinder.

29. The gas spring powered fastener driver of claim 28, wherein: The tank divider changes from a neutral position to an expanded position, wherein in the neutral position the tank divider has a first volume, and wherein in the expanded position the tank divider has a second volume that is greater than the first volume.

30. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; as well as an auxiliary tank fluidly coupled to the reservoir cylinder and including a valve; The valve opens in response to the pressure of the air in the cylinder of the storage chamber reaching a predetermined pressure.

31. The gas spring powered fastener driver of claim 30, wherein: The auxiliary tank is filled with pressurized air to a pressure higher than the pressure of the air within the reservoir cylinder.

32. The gas spring powered fastener driver of claim 31, wherein: In response to a decrease in the pressure of the air within the reservoir cylinder, the valve opens to allow air from the auxiliary tank to enter the reservoir cylinder.

33. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; as well as a pressure regulator fluidly coupled to the reservoir cylinder and including an adjustable portion; When the adjustable portion is adjusted, the volume of the storage chamber cylinder changes.

34. The gas spring powered fastener driver of claim 33, wherein: Rotating the adjustable portion changes the volume of the reservoir cylinder.

35. The gas spring powered fastener driver of claim 33, wherein: The adjustable portion is capable of moving between a neutral position, a first position, and a second position, and wherein, in the first position and the second position, the volume of the storage chamber cylinder changes from a neutral state, and wherein, in the neutral position, the volume of the storage chamber cylinder remains in the neutral state.

36. The gas spring powered fastener driver of claim 35, wherein: The pressure regulator comprises a stop means interacting with a corresponding protrusion in the reservoir cylinder or comprises a protrusion interacting with a corresponding detent means in the reservoir cylinder to retain the adjustable portion in each position.

37. The gas spring powered fastener driver of claim 33, wherein: The pressure regulator includes an indicator positioned on an exterior surface of the fastener driver.

38. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; as well as A pressure regulating system comprising a first check valve positioned in the wall of the cylinder, a second check valve positioned in the wall of the cylinder, and A third check valve is provided in the wall of the storage chamber cylinder.

39. The gas spring powered fastener driver of claim 38, wherein: When the pressure of the air within the cylinder reaches a predetermined level, the first and second check valves open to allow pressurized air to enter the reservoir cylinder.

40. The gas spring powered fastener driver of claim 39, wherein: When the pressure within the reservoir cylinder reaches a predetermined level, the third check valve opens to the external environment to at least partially depressurize the reservoir cylinder.

41. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; as well as a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; The lifter rotates 16 to 18 times to move the piston from the bottom dead center position to the top dead center position.

42. The gas spring powered fastener driver of claim 41, wherein: The driver blade includes a notch that interacts with a pawl to retain the driver blade in various positions between the bottom dead center position and the top dead center position.

43. The gas spring powered fastener driver of claim 42, wherein: The pawl holds the drive in a low power position, a medium power position, and a high power position, and wherein in the low power position, the lifter rotates 16 times from the bottom dead center position, in the medium power position, the lifter rotates 17 times from the bottom dead center position, and in the high power position, the lifter rotates 18 times from the bottom dead center position.

44. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; as well as a sliding seal disposed between the piston and the cylinder; The sliding seal is configured to prevent pressurized air from passing through the annular space between the piston and the cylinder only in a single direction of movement of the piston between the top dead center position and the bottom dead center position.

45. The gas spring powered fastener driver of claim 44, wherein: The sliding seal includes a ring and a wall integrally formed with the ring, wherein the ring extends inwardly into a groove formed in the piston, and wherein the wall is positioned along an outer peripheral surface of the piston.

46. ​​The gas spring powered fastener driver of claim 44, wherein: The sliding seal includes a first arm and a second arm extending from the wall, and wherein the first arm and the second arm are angled away from each other.

47. The gas spring powered fastener driver of claim 44, further comprising a valve positioned between the cylinder and the reservoir cylinder.

48. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; as well as a pressure relief valve, the pressure relief valve being disposed between the cylinder and the storage chamber cylinder; wherein the pressure relief valve is adjustable from a closed state to an open state in response to the pressure of the air within the cylinder reaching a predetermined pressure, and wherein the pressure relief valve transfers air from the cylinder to the reservoir cylinder when in the open state.

49. The gas spring powered fastener driver of claim 48, wherein: The cylinder includes a port fluidly coupling the cylinder to the reservoir cylinder, and wherein the pressure relief valve seals the port when in the closed state.

50. The gas spring powered fastener driver of claim 49, wherein: The pressure relief valve is a slidable plug that is spring biased into the orifice.

51. The gas spring powered fastener driver of claim 49, wherein: The pressure relief valve is an O-ring disposed over the opening of the orifice, and wherein the O-ring is configured to deform from the closed state to the open state in response to the pressure of the air within the cylinder reaching the predetermined pressure.

52. The gas spring powered fastener driver of claim 49, wherein: The pressure relief valve is a band disposed over the opening of the orifice, and wherein the band is configured to deform from the closed state to the open state in response to the pressure of the air within the cylinder reaching the predetermined pressure.

53. The gas spring powered fastener driver of claim 49, wherein: The pressure relief valve is a seal having an arm disposed over the opening of the orifice, and wherein the seal is configured to deform from the closed state to the open state in response to the pressure of the air within the cylinder reaching the predetermined pressure.

54. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; as well as A pump driven by the lifter to discharge pressurized air into the storage chamber cylinder, the pump comprising a pump piston driven by the lifter to reciprocate within the pump chamber, and A valve selectively fluidly couples the pump chamber to the reservoir cylinder to exhaust pressurized air within the pump chamber into the reservoir cylinder.

55. The gas spring powered fastener driver of claim 54, wherein: The lifter engages the pump piston when the piston is in the bottom dead center position.

56. The gas spring powered fastener driver of claim 54, wherein: The pump piston is movable between a bottom dead center position and a top dead center position, and wherein the lifter moves the pump piston from the bottom dead center position to the top dead center position.

57. The gas spring powered fastener driver of claim 56, wherein: The pump piston is urged by a spring from the bottom dead center position to the top dead center position.

58. The gas spring powered fastener driver of claim 54, further comprising a relief valve configured to exhaust air from the reservoir cylinder to the external environment when the pressure of the air within the reservoir cylinder reaches a predetermined pressure.

59. A gas spring powered fastener driver, characterized in that: include: cylinder; a reservoir cylinder having pressurized air in communication therewith; a movable piston positioned within the cylinder; a driver blade attached to the piston and movable with the piston between a top dead center position and a bottom dead center position, the driver blade defining a drive axis; a lifter operable to move the driver blade from the bottom dead center position toward the top dead center position, the lifter configured to engage the driver blade while moving the driver blade from the bottom dead center position toward the top dead center position; a valve positioned in the reservoir cylinder; wherein the valve adds pressurized air from the cylinder to the reservoir cylinder in response to the piston moving toward the bottom dead center position.

60. The gas spring powered fastener driver of claim 59, further comprising a buffer positioned vertically below the piston to absorb impact energy from the piston, and wherein The valve adds the pressurized air to the reservoir cylinder in response to the piston compressing the bumper while absorbing impact energy from the piston.

61. The gas spring powered fastener driver of claim 59, further comprising a sliding seal disposed between the piston and the cylinder, and wherein: The valve adds the pressurized air to the reservoir cylinder in response to the sliding seal creating a pressure differential in the cylinder as the piston moves toward the bottom dead center position.

Images