Patent Application
20090272556
The present invention relates to angle heads for power tools.
In one embodiment, the invention provides an angle head for use with a power tool that includes an angle housing defining first and second non-parallel axes, and a pinion shaft supported within the angle housing for rotation about the first axis. The pinion shaft has a first end that includes a plurality of pinion teeth, and a second end adapted to be engaged by a motor of a power tool. The angle head also includes a bevel gear supported in the angle housing for rotation about the second axis. The bevel gear includes an upper shaft, a toothed portion, and an output spindle. The upper shaft, toothed portion, and output spindle are integrally formed as a single, monolithic structure. The toothed portion is between the upper shaft and output spindle. The toothed portion includes a plurality of bevel teeth in meshing engagement with the pinion teeth such that rotation of the pinion shaft about the first axis causes rotation of the bevel gear about the second axis.
In another embodiment the invention provides a method of producing an angle head for use with a power tool. The method includes the steps of: (a) providing an angle housing that defines first and second non-parallel axes; (b) supporting a pinion shaft in the angle housing for rotation about the first axis, the pinion shaft having a first end that includes a plurality of pinion teeth, and a second end adapted to be engaged by a motor of a power tool; (c) forging a bevel gear blank having a toothed portion with first and second opposite sides and a plurality of forged bevel teeth, an upper extension extending from the first side, and a lower extension extending from the second side; (d) machining the upper extension to form an upper support shaft and the lower extension to form an output spindle to turn the bevel gear blank into a bevel gear; and (e) supporting the bevel gear within the angle housing for rotation about the second axis, with the forged bevel teeth in meshing engagement with the pinion teeth of the pinion shaft such that rotation of the pinion shaft about the first axis causes rotation of the bevel gear about the second axis.
Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
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. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings.
The pinion shaft 24 has a first end 32 and a second end 34. The first end 32 is adapted to be coupled to the motor of the power tool 10. The pinion shaft 24 is rotatable under the influence of the motor within the angle housing 22 about the first axis 28. A bearing 38 is provided for supporting the pinion shaft 24 within the angle housing 22 for rotation about the first axis 28. The second end 34 of the pinion shaft 24 has pinion teeth 36 for engaging the gear assembly 26.
The gear assembly 26 includes a bevel gear 40, a thrust bearing 42, an axial bearing 44 and a retaining nut 46. The bevel gear 40 includes an upper shaft 48, a toothed portion 50, and an output spindle 52. The upper shaft 48 is supported for rotation about the second axis 30 with a bushing 54. The toothed portion 50 is located in between the upper shaft 48 and the output spindle 52 and includes bevel teeth 56. The bevel teeth 56 are sized and shaped to meshingly engage with the pinion teeth 36 of the pinion shaft 24. The output spindle 52 can have a standard square drive 55.
The thrust bearing 42 is trapped between the retaining nut 46 and the toothed portion 50 of the bevel gear 40. In some embodiments (not shown), the thrust bearing 42 is integrally formed with the retaining nut 46. The thrust bearing 42 helps to support the bevel gear 40 for rotation about the second axis 30 and resists movement of the bevel gear 40 in a direction parallel to the second axis 30. In some embodiments, the thrust bearing 42 is a needle bearing. The gear assembly 26 can include a flat washer 57 between the retaining nut 46 and the thrust bearing 42.
The axial bearing 44 surrounds the output spindle 52 and is sandwiched between the retaining nut 46 and the output spindle 52. In some embodiments, the axial bearing 44 is press fit to the inside surface 58 of the retaining nut 46. The axial bearing 44 is separate from the thrust bearing 42 and resists movement of the bevel gear 40 in a direction perpendicular to the second axis 30. In some embodiments (not shown), the axial bearing 44 is integrally formed with the retaining nut 46.
The retaining nut 46 has an inner surface 58 and an outer surface 60. The outer surface 60 is threaded for engagement with an inner surface 62 of the angle housing 22 to secure the retaining nut 46 to the angle housing 22. The inner surface 58 surrounds the axial bearing 44 and the output spindle 52.
The gear assembly 26 can be assembled with the angle housing 22 by sequentially dropping the components of the gear assembly 26 through an opening 64 in the angle housing 22. First, the bushing 54 is dropped into a recess 66 in the angle housing 22 (see
The angle head 16 transmits rotation of the pinion shaft 24 about the fist axis 28 to rotation of the output spindle 52 about the second axis 30. To do this, the pinion teeth 36 of the pinion shaft 24 meshingly engage the bevel teeth 56 of the bevel gear 40. As the pinion shaft 24 rotates about the first axis 28, the pinion teeth 36 drive rotation of the output spindle 52. The thrust bearing 42 and the axial bearing 44 support the bevel gear 40 for rotation. The thrust bearing 42 resists movement of the bevel gear 40 in a direction parallel to the second axis 30, while the axial bearing 44 resists movement of the bevel gear 40 in a direction perpendicular to the second axis 30.
The power tool 10 can be useful in order to position the output spindle 52 of the tool 10 in an orientation that is convenient for the task that is being performed while permitting the operator to grasp and manipulate the power tool 10 with the hand grip 18 in an orientation that is convenient for the operator. A head height dimension 70 of the angle head 16 is illustrated in
Referring now to
In the second step, the blank 100 of
Thus, the invention provides, among other things, an angle head for use with a power tool. Various features and advantages of the invention are set forth in the following claims.
