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The present disclosure relates impact wrenches that utilize a motor to power an impact device that can forcefully rotate threaded fasteners, and more particularly, to angled impact wrenches that drive the fasteners about a drive axis that is non-parallel to an rotational axis of an drive shaft of the motor, with the drive axis typically being at a right-angle to the rotational axis of the drive shaft. While such devices are known and suitable for many purposes, there are still limitations to their use. Accordingly, there is a continuing desire to improve such devices, including by increasing their usefulness to a user by expanding the devices ability to accommodate a variety of uses.
In accordance with one feature of this disclosure, an angled impact wrench is capable of driving a fastener onto a workpiece that extends completely through a portion of the impact wrench. The impact wrench includes a housing; a motor mounted in the housing, the motor having an output shaft rotatable about a first axis; and an impact drive unit mounted in the housing for rotation about a second axis that is nonparallel to the first axis. The impact drive unit has an energy storing condition and an energy release condition, and is configured to repeatedly cycle between the energy storing condition and the energy release condition in response to a drive torque supplied by the motor via the output shaft. The impact drive unit having a through passage extending along the second axis to allow a workpiece to extend completely through the impact wrench.
In one feature, the angled impact wrench further includes a gear train mounted in the housing to transfer a drive torque from the output shaft of the motor to the impact drive unit. In a further feature, the gear train includes a first bevel gear mounted in the housing for rotation about the first axis and operably connected to the output shaft to be rotationally driven by the motor; and a second bevel gear mounted in the housing for rotation about the second axis. The second bevel gear surrounds a portion of the impact drive unit and is meshed with the first bevel gear to rotationally driven by the motor. In yet a further feature, the gear train further includes a planetary gear train including a sun gear driven by the output shaft of the motor and a planet gear carrier driving the first bevel gear. The sun gear and the planet gear carrier are mounted for rotation about the first axis.
According to one feature, the impact drive unit includes a rotatable hammer and a rotatable anvil mounted in the housing for rotation about the second axis. The rotatable hammer impacts the rotatable anvil with the impact drive unit in the energy release condition to create a drive torque at an output of the impact drive unit. In a further feature, the rotatable hammer has a through bore extending along the second axis, and the rotatable anvil has a through bore extending along the second axis. The through bores defining a portion of the through passage.
As one feature, the impact drive unit includes a spring mounted to store energy with the impact drive unit in the energy storing condition and to release energy with the impact drive unit in the energy release condition. In a further feature, the impact drive unit further includes mating ball ramps configured to generate an axial compression force with the impact drive unit in the energy storing condition.
In accordance with one feature of this disclosure, the impact drive unit includes an input shaft, a rotatable hammer, a compression spring, and a rotatable anvil. The input shaft is mounted in the housing for rotation about the second axis and operably connected to the output shaft to be rotationally driven about the second axis by the motor. The input shaft has a through bore centered on the second axis to allow a workpiece to extend completely through the impact wrench along the second axis, and a cam feature on an outer surface of the input shaft. The rotatable hammer is mounted in the housing for rotation about the second axis and has a through bore centered on the second axis and surrounding a portion of the input shaft, a cam feature on an inner surface of the through bore of the rotatable hammer and operably connected to the cam feature on the input shaft to translate the rotatable hammer along the second axis relative to the input shaft over a limited linear distance in response to rotation of the input shaft with the impact drive unit in the energy storing condition, and at least one impact surface. The compression spring is sandwiched between a surface on the input shaft and a surface on the rotatable hammer to store energy as the rotatable hammer translates over the limited linear distance with the impact drive unit in the energy storing condition and to transfer energy back to the rotatable hammer with the impact drive unit in the energy release condition. The rotatable anvil is mounted in the housing for rotation about the second axis and has a through bore centered on the second axis to allow a work piece to extend completely through the impact wrench along the second axis, and at least one impact surface engageable with the at least one impact surface of the rotatable hammer to receive an impact force from the rotatable hammer with the impact device in the energy release condition. The through bore of the rotatable anvil includes a drive feature to transfer a drive torque to a driven component received in the through bore of the rotatable anvil.
In one feature, the angled impact further includes a gear train operably connecting the output shaft of the motor to the input shaft of the impact drive unit. In a further feature, the gear train includes a first bevel gear mounted in the housing for rotation about the first axis and operably connected to the output shaft to be rotationally driven by the motor; and a second bevel gear mounted in the housing for rotation about the second axis. The second bevel gear surrounds a portion of the input shaft and is meshed with the first bevel gear to rotationally driven by the motor. In yet a further feature, the gear train further includes a planetary gear train including a sun gear driven by the output shaft of the motor and a planet gear carrier driving the first bevel gear. The sun gear and the planet gear carrier are mounted for rotation about the first axis.
According to one feature, the at least one impact surface of the rotatable hammer includes a first pair of circumferentially spaced surfaces, and the at least one impact surface of the rotatable hammer includes a second pair of circumferentially spaced surfaces.
As one feature, the cam feature on the input shaft is formed in a radially outwardly facing cylindrical surface of the input shaft; and the cam feature on the rotatable anvil is formed in a radially inwardly facing cylindrical surface of the anvil. In a further feature, the cam features are ball ramps connected by at least one ball bearing riding in the ball ramps.
In one feature, the through bore of the rotatable hammer includes a radially inwardly facing cylindrical surface that is sized for guided translation over a radially outwardly facing cylindrical surface on the input shaft.
According to one feature, the through bore in the input shaft includes a radially inwardly facing cylindrical bearing surface that receives a radially outwardly facing cylindrical journal surface on the rotatable anvil to form a rotatable bearing support for the input shaft.
In one feature, the angled impact wrench further includes a driven component in the form of a fastener drive socket engaged in the through bore of the rotatable anvil.
As one feature, the motor is an electric motor. In a further feature, the angled impact wrench of further includes a battery releasably connected to the housing and operably connected the electric motor to supply electric power to the electric motor.
It should be understood that the inventive concepts disclosed herein do not require each of the features discussed above, may include any combination of the features discussed, and may include features not specifically discussed above.
As best seen in
The impact drive unit 32 has an energy storing condition wherein energy is stored in a helical compression spring 39 of the impact drive unit 32 as elastic or spring potential energy, and an energy release condition wherein the potential energy stored in the spring 39 is converted to kinetic energy for driving a fastener 12. The impact drive unit 32 is configured to repeatedly cycle between the energy storing condition and the energy release condition in response to a drive torque supplied by the motor 26 via the output shaft 28 and the gear train 38.
The impact drive unit 32 includes an input shaft 40, a rotatable hammer 42, and a rotatable anvil 44, all of which are mounted in the housing for rotation about the drive axis 34. As best seen in
In the illustrated and preferred embodiment, the cam features 48 and 56 are shown in the form of ball ramps 48 and 56 that are operably connected by spherical ball bearings 64, shown in
The components 40, 42, 44 and 64 of the impact drive unit 33 can be made from any suitable material, and in the illustrated embodiment are made from a suitable hardened steel material.
Annular washers 76 and 78 are provided between the spring 39 and the annular surfaces 60 and 62 to reduce rotational friction generated between the spring 39 and the input shaft 40 and rotatable hammer 42. A radial journal bearing or bushing 80 is provided between the housing 20 and a cylindrical outer surface 82 on the rotatable anvil 44 and an annular busing 84 and washer 85 are provided between the housing 20 and an annular surface 86 on the rotatable anvil 44 to rotatably mount the anvil 44 in the housing 20. The rotatable anvil 44 further includes an outwardly facing cylindrical surface 88 that is received in an inwardly facing cylindrical surface 90 formed in the bore 46 to provide a rotational mount for one end of the input shaft 40.
The gear train 38 includes a pair of mating bevel gears 92 and 94. The bevel gear 94 is mounted in the housing 20 for rotations about the drive axis 34 by a ball bearing 96. The bevel gear 94 includes a cylindrical through bore 98 (best seen in
As best seen in
In the illustrated embodiment, the impact wrench 10 includes an electronic motor controller 160 mounted in the housing 20 and operably coupled to the variable trigger switch 26 to control the rotational speed of the motor 28 in response to a user compressing the switch 26, typically with the user's index finger while the user's hand grasps the grip 22 formed on the housing 20. The wrench 10 of the illustrated embodiment also includes a rechargeable battery 162, shown in
The housing 20 of the illustrated embodiment is a multi-piece assembly that includes two main housing halves 170 and 172, a bell housing 174, and an end cap 176, all of which are fixed together with suitable threaded fasteners 178. The housing 20 can be of any suitable material, and in the illustrated embodiment, the halves are made from a suitable injection molded polymer and the bell housing 174 and end cap are made from a suitable metal material.
Preferred embodiments of the inventive concepts are described herein, including the best mode known to the inventor(s) for carrying out the inventive concepts. Variations of those preferred embodiments will become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventor(s) expect skilled artisans to employ such variations as appropriate, and the inventor(s) intend that the inventive concepts can be practiced otherwise than as specifically described herein. Accordingly, the inventive concepts disclosed herein include all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements and features in all possible variations thereof is encompassed by the inventive concepts unless otherwise indicated herein or otherwise clearly contradicted by context. Further in this regard, while highly preferred forms of the angled impact wrench 10 are shown in the figures, it should be understood that this disclosure anticipates variations in the specific details of each of the disclosed components and features of the angled impact wrench 10 and that no limitation to a specific form, configuration, or detail is intended unless expressly and specifically recited in an appended claim.
For example, while specific and preferred forms have been shown for the orientation of the grip 22 on the housing 20, in some applications it may be desirable for the grip 22 to have a different orientation or configuration. As another example, while a specific form and construction has been shown for the housing 20, other suitable forms and constructions can be used. As another example, while a specific configuration has been shown for the gear train 38, in some applications other configurations of gear trains may be used, or other types of operable connections can be used to transfer the drive torque from the motor 26 to the impact drive unit 32, including for example, a belt or chain drive.
As yet another example, while specific configurations have been shown for the components of the impact drive unit 32, other configurations and/or components may be desirable in some applications. For example, while a helical compression spring 39 made of a suitable spring steel is preferred, in some applications other types and/or configurations may be desirable, such as wave springs, and any suitable spring made of any suitable material may be used. As another example, while the annular washers 76 and 78 are preferred to reduce the rotational friction between the spring 39 and the rotatable hammer 42, other means for reducing the rotational friction, including, for example, ball bearings received in an annular groove, such as the groove 180 shown in
As further examples, while the variable speed trigger switch 24 is preferred, in some applications it may be desirable for a different type of switch to be used, including, for example, a non-variable speed trigger switch or an on/off toggle switch, and any suitable switch, many of which are known, can be use. As another example, while a brushless, radial flux, electric motor 26 is preferred, in some applications other types of electric motors may be desirable and any suitable electric motor, many of which are known, can be used. In another example, while it is preferred that the angled impact wrench 10 be powered by any suitable removable, rechargeable battery 162, many of which are known, in some applications it may be desirable for the wrench 10 to be powered by non-rechargeable and/or non-removable batteries, or to be powered by an electric cord that can be connected to a power outlet. As another example, while keys 102 and 114 are disclosed herein for the purpose of forming an anti-rotation connection between selected components, any suitable anti-rotation could be used, such as, for example, a toothed spline connection, such as the toothed spline 180 shown as an alternate configuration on the output shaft 28 of the motor 26 in
The use of the terms “a” and “an” and “the” and “at least one” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The use of the term “at least one” followed by a list of one or more items (for example, “at least one of A and B”) is to be construed to mean one item selected from the listed items (A or B) or any combination of two or more of the listed items (A and B), unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the inventive concepts disclosed herein and does not pose a limitation on the scope of any invention unless expressly claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the inventive concepts disclosed herein.
All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.
Number | Name | Date | Kind |
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20120118596 | Scott | May 2012 | A1 |
20140157961 | Chen | Jun 2014 | A1 |
Number | Date | Country | |
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20200406434 A1 | Dec 2020 | US |