阅读说明：本技术 驱动器刀片 (Driver blade ) 是由 欧阳晓川 D·A·彼尔德曼 于 2019-01-15 设计创作，主要内容包括：一种与动力紧固件驱动器一起使用的驱动器刀片,其包括限定纵向轴线的细长主体。主体包括顶表面和与顶表面相对的底表面。第一边缘在顶表面和底表面之间延伸。驱动器刀片还包括沿第一边缘形成并在横向于纵向轴线的方向上延伸的多个齿。驱动器刀片使用金属注射成型工艺制造。(A driver blade for use with a powered fastener driver includes an elongated body defining a longitudinal axis. The body includes a top surface and a bottom surface opposite the top surface. The first edge extends between the top surface and the bottom surface. The driver blade also includes a plurality of teeth formed along the first edge and extending in a direction transverse to the longitudinal axis. The driver blade is manufactured using a metal injection molding process.)

1. A driver blade for a powered fastener driver, said driver blade comprising:

an elongated body defining a longitudinal axis, the elongated body comprising:

a top surface and a bottom surface, the bottom surface being opposite the top surface,

a first edge extending between the top surface and the bottom surface; and

a plurality of teeth formed along the first edge and extending in a direction transverse to the longitudinal axis,

wherein the driver blade is manufactured using a metal injection molding process.

2. The driver blade of claim 1, wherein the elongated body is made of a first material, and wherein the metal injection molding process is a one-shot metal injection molding process.

3. The driver blade of claim 2, wherein the first material comprises an iron alloy composition.

4. The driver blade of claim 3, wherein the ferrous alloy composition comprises an alloy of carbon, chromium, iron, manganese, molybdenum, silicon, and/or vanadium.

5. The driver blade of claim 3, wherein the ferrous alloy composition consists essentially of, by weight, 0.45% to 0.55% carbon, 3% to 3.5% chromium, 92% to 94.9% iron, 0.2% to 0.9% manganese, 1.3% to 1.8% molybdenum, 0.2% to 1% silicon, and 0.2% to 0.3% vanadium.

6. The driver blade of claim 1 wherein the elongated body is made of a first material and the teeth are made of a second material, and wherein the metal injection molding process is a two shot metal injection molding process wherein the elongated body and the teeth are joined without the need for additional manufacturing steps.

7. The driver blade of claim 6, wherein the first material and the second material each comprise an iron alloy composition.

8. The driver blade of any of claims 1 to 7, wherein the elongated body comprises a first end having a threaded post for connection to a piston of the powered fastener driver.

9. The driver blade of claim 8, wherein the elongated body includes a second end opposite the first end, and wherein the second end is oriented perpendicular to the longitudinal axis.

10. The driver blade of any of claims 1-7 wherein the elongated body comprises a second edge extending between the top surface and the bottom surface, wherein the second edge is located on an opposite side of the longitudinal axis from the first edge, and wherein the driver blade further comprises a plurality of protrusions formed along the second edge and extending in a direction transverse to the longitudinal axis.

11. A method of making a driver blade for a powered fastener driver, the method comprising:

mixing a first material in powder form with a binder composition to produce a first raw material mixture;

injecting the first raw material mixture into a mold to form a green driver blade;

removing the adhesive composition from the green driver blade; and

heat treating the green driver blade to reduce porosity of the green driver blade to produce a finished driver blade usable with the powered fastener driver.

12. The method of claim 11, wherein the first material is a ferrous alloy composition.

13. The method of claim 12, wherein the ferroalloy composition comprises an alloy of carbon, chromium, iron, manganese, molybdenum, silicon, and/or vanadium.

14. The method of claim 13, wherein the ferroalloy composition consists essentially of, by weight, 0.45% to 0.55% carbon, 3% to 3.5% chromium, 92% to 94.9% iron, 0.2% to 0.9% manganese, 1.3% to 1.8% molybdenum, 0.2% to 1% silicon, and 0.2% to 0.3% vanadium.

15. The method of claim 11, further comprising:

mixing a second material in powder form with a second binder composition to produce a second raw material mixture; and

injecting the second raw material mixture into the mold to form the green driver blade.

16. The method of claim 15, wherein injecting the first raw material mixture comprises injecting the first raw material mixture into a first portion of the mold to form a first portion of the green driver blade, and wherein injecting the second raw material mixture comprises injecting the second raw material mixture into a second portion of the mold to form a separate second portion of the green driver blade.

17. The method of claim 16, wherein the first portion of the green driver blade is an elongated body of the driver blade, and wherein the second portion of the green driver blade is a plurality of teeth formed along an edge of the elongated body.

18. The method of any of claims 11 to 17, wherein removing the adhesive composition from the green driver blade comprises passing the green driver blade through a chemical wash or using a thermal evaporation process.

19. The method of any of claims 11 to 17, wherein heat treating the green driver blade comprises sintering the green driver blade.

20. The method of claim 19, wherein sintering the green driver blade comprises using a hot isostatic pressing process to increase a density of the green driver blade.

Technical Field

The present invention relates to powered fastener drivers, and more particularly to driver blades for use with powered fastener drivers.

Background

Various fastener drivers for driving fasteners (e.g., nails, tacks, staples, etc.) into workpieces are known in the art. These fastener drivers utilize various methods known in the art (e.g., compressed air produced by an air compressor, electrical power, a freewheel mechanism, etc.) to drive the driver blade from a top dead center position to a bottom dead center position.

Disclosure of Invention

In one aspect, the present invention provides a driver blade for a powered fastener driver. The driver blade includes an elongated body defining a longitudinal axis. The body includes a top surface and a bottom surface opposite the top surface. The first edge extends between the top surface and the bottom surface. The driver blade also includes a plurality of teeth formed along the first edge and extending in a direction transverse to the longitudinal axis. The driver blade is manufactured using a metal injection molding process.

In another aspect, the present invention provides a method of making a driver blade for a powered fastener driver. The method includes mixing a first material in powder form with a binder composition to produce a first raw material mixture. The method also includes injecting the first raw material mixture into a mold to form a green driver blade. The method further includes removing the adhesive composition from the green driver blade and heat treating the green driver blade to reduce the porosity of the green driver blade to produce a finished driver blade useful for a powered fastener driver.

Other features and aspects of the present invention will become apparent by consideration of the following detailed description and accompanying drawings.

Drawings

FIG. 1 is a perspective view of a powered fastener driver according to one embodiment of the invention.

Fig. 2 is a perspective view of a driver blade of the powered fastener driver of fig. 1.

Fig. 3A is a perspective view of a driver blade according to another embodiment of the invention.

Fig. 3B is a side view of the driver blade of fig. 3A.

Fig. 4 is a schematic diagram of a process for manufacturing the driver blade of fig. 2 or the driver blades of fig. 3A-3B.

Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting.

Detailed Description

Referring to FIG. 1, a gas spring powered fastener driver 10 is operable to drive fasteners (e.g., nails, tacks, staples, etc.) held within a magazine 14 into a workpiece. The fastener driver 10 includes an air cylinder 18. A movable piston (not shown) is located within the cylinder 18. Referring to fig. 2, the fastener driver 10 also includes a driver blade 26, the driver blade 26 being attached to the piston and movable therewith. The fastener driver 10 does not require an external source of air pressure, but rather includes pressurized air in the air cylinder 18.

Referring to fig. 1, the fastener driver 10 includes a housing 30, the housing 30 having a cylinder housing portion 34 and a motor housing portion 38 extending therefrom. The cylinder housing portion 34 is configured to support the cylinder 18, while the motor housing portion 38 is configured to support the motor 42 and the transmission 44 downstream of the motor 42. In addition, the illustrated housing 30 includes a handle portion 46 extending from the cylinder housing portion 34, and a battery attachment portion 50 coupled to an opposite end of the handle portion 46. The battery 54 may be electrically connected to the motor 42 for powering the motor 42. The handle portion 46 supports a trigger 56, which trigger 56 is depressed by a user to initiate a drive cycle of the fastener driver 10.

Referring to fig. 2, the driver blade 26 defines a longitudinal axis 58. During a drive cycle, the driver blade 26 and piston may move along the axis 58 within the cylinder 18 between a Top Dead Center (TDC) or ready position and a Bottom Dead Center (BDC) or drive position. The fastener driver 10 also includes a lifter assembly (not shown) that is powered by the motor 42 (fig. 1) and is operable to return the driver blade 26 from the drive position to the ready position.

With continued reference to fig. 2, the driver blade 26 includes an elongated body 66, the elongated body 66 having a first planar surface (i.e., a front surface 68) and an opposing second planar surface (i.e., a rear surface 70). A first edge 74 extends between the front and rear surfaces 68, 70 along one side of the body 66, and a second edge 78 extends between the front and rear surfaces 68, 70 along an opposite side of the body 66. The front surface 68 is parallel to the rear surface 70. Likewise, the edges 74, 78 are also parallel.

The driver blade 26 includes a plurality of lift teeth 82 formed along the first edge 74 of the body 66. The first edge 74 extends in the direction of the axis 58, and the lifting teeth 82 project from the first edge 74 in a direction transverse to the axis 58. During the return of the driver blade 26 from the drive position to the ready position, the lifting teeth 82 sequentially engage the lifter assembly.

The driver blade 26 also includes a first end 90 and a second end 94 opposite the first end 90. The front and rear surfaces 68, 70 and the first and second edges 74, 78 extend between the first and second ends 90, 94. In the embodiment of the driver blade 26 shown, the first end 90 includes a threaded post for connection with a piston. The second end 94 of the driver blade 26 is oriented perpendicular to the axis 58 for impacting fasteners fed from the magazine 14 and driving the fasteners into a workpiece.

Fig. 3A-3B illustrate a driver blade 26a according to another embodiment of the invention, wherein reference numerals for features similar to the driver blade 26 shown in fig. 2 are appended with the letter "a". The driver blade 26a includes a plurality of lift teeth 82a extending from the first edge 74 a. In addition, the driver blade 26a includes a plurality of projections 86 extending from the second edge 78 a. In particular, the protrusion 86 extends from the second edge 78a in a direction transverse to the longitudinal axis 58 a. In one embodiment, the plurality of protrusions 86 are configured to engage a latch (not shown) of the fastener driver 10 to prevent the driver blade 26a from moving toward the driving position.

Traditionally, forging and/or machining processes are used to manufacture the driver blade as shown in fig. 2-3B. However, in the illustrated embodiment, the driver blades 26, 26a are manufactured using an insert molding process, such as a one-time metal injection molding ("MIM") process. In such a one-time metal injection molding process, the driver blade 26, 26a is made of a first material 110 (e.g., a metal or metal alloy) having a first hardness. The first hardness of the first material 110 is selected to be at least a minimum and at least as hard as the components of the lifter assembly that contact the lifting teeth 82, 82a to reduce wear of the driver blades 26, 26a during use of the fastener driver 10. In one embodiment, the first material 110 includes an iron alloy composition. For example, the iron alloy composition may include an alloy of carbon, chromium, iron, manganese, molybdenum, silicon, and/or vanadium. In the illustrated embodiment of the driver blade 26, 26a, the iron alloy composition consists essentially of (by weight): 0.45% to 0.55% carbon, 3% to 3.5% chromium, 92% to 94.9% iron, 0.2% to 0.9% manganese, 1.3% to 1.8% molybdenum, between 0.2% to 1% silicon, and between 0.2% to 0.3% vanadium.

In another embodiment, the driver blade 26, 26a may be formed using more than one material, such that the driver blade 26, 26a is manufactured using a multi-shot metal injection molding process. For example, the body 66, 66a of the driver blade 26, 26a may be made of a first material 110 having a first hardness, and the lifting teeth 82, 82a (and optionally the protrusion 86) may be made of a second material 114 having a second, different hardness. In this example, the metal injection molding process is a two shot metal injection molding process. The first material 110 and the second material 114 are selected such that the second hardness is greater than the first hardness. Thus, the hardness of the lifting teeth 82, 82a is greater than the hardness of the main body 66, 66a to reduce wear of the lifting teeth 82, 82a during use of the fastener driver 10. Since the different materials 110, 114 of the main bodies 66, 66a and the lifting teeth 82, 82a, respectively, are joined or integrally formed during the two-shot metal injection molding process, a secondary manufacturing process for attaching the lifting teeth 82, 82a to the main bodies 66, 66a is unnecessary. In one embodiment, the second material 114 may also include a ferrous alloy composition.

In other embodiments of the driver blade 26, 26a, other portions may be made of different materials to provide different material properties (e.g., hardness) to the respective portions of the driver blade 26, 26 a. For example, the second end 94, 94a of the driver blade 26, 26a that strikes the fastener during a fastener driving operation may be made of a harder material than the remainder of the body 66, 66 a.

Referring to fig. 4, the metal injection molding process sequentially includes a raw material mixing process 116 of mixing the first material 110 with the adhesive composition 118, an injection molding process 122 using a mold 126, a debinding process 130 of removing the adhesive composition 118, and a heat treatment process 134.

During the raw material mixing process 116, a binder composition 118 is added to the first material 110 to facilitate processing by the injection molding process 122. As a result, the first material 110 in powder form is uniformly mixed with the binder composition 118 to provide a first raw material mixture 138 having a determined consistency. In the case of a two shot metal injection molding process, the second material 114, also in powder form, is also uniformly mixed with the binder composition 118 to provide a second raw material mixture 142 having substantially the same consistency as the first mixture 138. In the illustrated embodiment of the driver blades 26, 26a, the adhesive composition 118 comprises a thermoplastic adhesive. Alternatively, the adhesive composition 118 may include other suitable adhesive compositions (e.g., wax). The amount of binder composition 118 in each of the first raw material mixture 138 and the second raw material mixture 142 is selected to match the shrinkage of the bodies 66, 66a and the lifting teeth 82, 82a, respectively, during a sintering process 166 described below.

The injection molding process 122 includes processing the first raw material mixture 138 and the second raw material mixture 142 by an injection molding machine 150. In particular, the process 122 includes injecting a first raw material mixture 138 into the mold 126. In the case of a two shot metal injection molding process, a first raw material mixture 138 is injected into a first portion of the mold 126 and a second raw material mixture 142 is injected into a second portion of the mold 126. Upon completion of the injection molding process 122, a temporary or green (referred to in the metal injection molding industry as a "green") driver blade 154 is manufactured to include the first material 110 (and the second material 114 if a two shot metal injection molding process) and the binder composition 118. Due to the presence of the binder composition 118, the "green" driver blade 154 is larger than the finished driver blade 26, 26 a.

After the injection molding process 122, the "green" driver blade 154 is removed from the mold 126 and then subjected to the debinding process 130. The debinding process 130 removes the adhesive composition 118. During the debinding process 130, the "green" driver blade 154 is transformed into a "brown" driver blade 158 (as known in the metal injection molding industry) that includes only the first material 110 (and the second material 114 if a two shot metal injection molding process). In the illustrated embodiment, the debinding process 130 includes a chemical wash 162. Alternatively, the debinding process 130 may include a thermal evaporation process to remove the binder composition 118 from the "green" driver blade 154. The "brown stock" driver blade 158 is brittle and porous without the adhesive composition 118.

To reduce the porosity of the "brown stock" driver blade 158, the heat treatment process 134 is performed to diffuse the atoms of the "brown stock" driver blade 158 to form the finished tool head 26, 26 a. The heat treatment process 134 exposes the "brown stock" driver blade 158 to elevated temperatures to promote atomic diffusion, allowing the atoms to interact and fuse together. In the illustrated embodiment, the heat treatment process 134 includes a sintering process 166. Alternatively, the debinding process 130 and the heat treatment process 134 may be combined into a single process such that at lower temperatures, thermal evaporation will occur in the debinding process 130 that removes the adhesive composition 118. Also, at higher temperatures, atomic diffusion will reduce the porosity in the "brown stock" driver blade 158 to produce the final finished driver blade 26, 26 a.

In some embodiments, the sintering process 166 includes a Hot Isostatic Pressing (HIP) process that utilizes high pressure and temperature for a predetermined amount of time to give the component (e.g., the driver blade 26, 26a) a higher density. In one example, the "brown stock" driver blade 158 is located in a high temperature furnace that is enclosed in a pressure vessel. Any voids within the "brown stock" driver blade 158 collapse and fuse together at high pressure and temperature to eliminate any defects within the "brown stock" driver blade 26, 26 a. In this way, the driver blades 26, 26a subjected to the hot isostatic pressing process may have an increase in density, a decrease in porosity throughout the driver blades 26, 26a, and/or a decrease in microcracks.

The metal injection molding process allows for the manufacture of driver blades 26, 26a having relatively complex shapes without the need for post-forming processes (i.e., machining), thus reducing costs compared to other manufacturing processes, such as forging and machining. Further, with a multi-step metal injection molding process, different portions of the driver blade 26, 26a may be made of different materials to provide different material properties (e.g., hardness) for the respective portions of the driver blade 26, 26 a. Thus, the performance and wear characteristics of the driver blades 26, 26a may be improved without the attendant cost of using multiple different manufacturing and assembly processes to separately form and then connect the different portions of the driver blades 26, 26 a.

Various features of the invention are set forth in the following claims.