FIELD OF THE INVENTION
The present invention relates to power tools, and more particularly to angle grinders.
BACKGROUND OF THE INVENTION
Angle grinders typically include a rotatable grinding disc and a guard partially surrounding the disc. In some instances, it might be desirable to adjust the position of the guard to expose different regions of the disc while grinding a workpiece.
SUMMARY OF THE INVENTION
The present invention provides, in one aspect, an angle grinder including a motor housing, a motor supported within the motor housing, a spindle oriented transverse to the motor and configured to receive torque therefrom, causing the spindle to rotate, a spindle housing from which the spindle extends, and a guard coupled to the spindle housing and including a shroud that at least partially surrounds the spindle and an attached grinding disc coupled to the spindle. An orientation of the guard is adjustable relative to the spindle housing by rotating the guard about a rotational axis of the spindle. The angle grinder also includes a locking mechanism operable between a locking state, in which the guard is rotationally immovable relative to the spindle housing, and a release state, in which the guard is rotatable about the rotational axis to adjust the orientation of the guard. The locking mechanism includes a lever having a first actuation portion proximate a first side of the spindle housing configured to be pressed by a user to adjust the locking mechanism from the locking state to the release state, and a second actuation portion proximate a second side of the spindle housing configured to be alternately pressed by the user to adjust the locking mechanism from the locking state to the release state.
The present invention provides, in another aspect, an angle grinder including a motor housing, a motor supported within the motor housing, a spindle oriented transverse to the motor and configured to receive torque therefrom, causing the spindle to rotate, a spindle housing from which the spindle extends, and a guard coupled to the spindle housing and including a shroud that at least partially surrounds the spindle and an attached grinding disc coupled to the spindle. An orientation of the guard is adjustable relative to the spindle housing by rotating the guard about a rotational axis of the spindle. The angle grinder also includes a locking mechanism operable between a locking state, in which the guard is rotationally immovable relative to the spindle housing, and a release state, in which the guard is rotatable about the rotational axis to adjust the orientation of the guard. The locking mechanism includes a detent having a first surface and an opposite, second surface and a first actuator proximate the first surface of the detent and a first side of the spindle housing. The first actuator is configured to be pressed by a user to adjust the locking mechanism from the locking state to the release state. The locking mechanism also includes a second actuator proximate the second surface of the detent and an opposite, second side of the spindle housing. The second actuator is configured to be alternately pressed by the user to adjust the locking mechanism from the locking state to the release state.
The present invention provides, in yet another aspect, an angle grinder including a motor housing, a motor supported within the motor housing, a spindle oriented transverse to the motor and configured to receive torque therefrom, causing the spindle to rotate, a spindle housing from which the spindle extends, and a guard coupled to the spindle housing and including a shroud that at least partially surrounds the spindle and an attached grinding disc coupled to the spindle. An orientation of the guard is adjustable relative to the spindle housing by rotating the guard about a rotational axis of the spindle. The angle grinder further includes a lever adjustable between a locking state and a release state. When in the locking state, the guard is immovable relative to the spindle housing. When in the release state, the guard is rotatable about the rotation axis to adjust the orientation of the guard. The lever is rotatable about a lever axis that is parallel to the spindle to adjust the lever between the locking state and the release state.
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
FIG. 1 is a perspective view of an angle grinder in accordance with an embodiment of the invention.
FIG. 2 is a cross-sectional view of the angle grinder of FIG. 1 through section 2-2 in FIG. 1.
FIG. 3 is an exploded perspective view of the angle grinder of FIG. 1, illustrating an adjustable guard and locking mechanism.
FIG. 4 is a cross-sectional view of the angle grinder of FIG. 1 through section 4-4 in FIG. 1, illustrating the adjustable guard and locking mechanism.
FIG. 5A is a plan view of the adjustable guard and locking mechanism of FIG. 4, where the locking mechanism is in a locking state.
FIG. 5B is a plan view of the adjustable guard and locking mechanism of FIG. 4, where the locking mechanism is in a release state.
FIG. 5C is a plan view of the adjustable guard and locking mechanism of FIG. 4, where the locking mechanism is in an alternate release state.
FIG. 6 is a plan view of an alternative embodiment of a locking mechanism for use with the angle grinder of FIG. 1.
FIG. 7 is a perspective view of an angle grinder including an adjustable guard and locking mechanism in accordance with another embodiment of the invention.
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
FIGS. 1-3 illustrate an angle grinder 10 including a motor housing 14, a spindle housing 18, and a guard 22 attached to the spindle housing 18 to partially cover a grinding disc 26. Alternatively, a buffing wheel, a cutting disk, or an abrasive brush may instead be used with the angle grinder 10. The angle grinder 10 includes an electric motor 30 supported within the motor housing 14 and a handle 34 extending reward from the motor housing 14 that a user can grasp while operating the angle grinder 10. The spindle housing 18 includes a cover portion 38 from which a spindle 42 extends and encloses a gear train 44 between the motor 30 and a spindle 42. With reference to FIG. 2, the gear train 44 includes a bevel pinion 46 that is integrally formed as a single piece with an output or rotor shaft 50 of the motor 30 and a bevel gear 54 coupled for co-rotation with the spindle 42 and meshed with the bevel pinion 46 to transfer torque from the motor 30 to the spindle 42, thereby rotating the spindle 42 and attached grinding disc 26.
With reference to FIG. 3, the cover portion 38 includes a neck 58 and a retaining groove 62 defined by a plurality of radially outward-extending tabs 66 from the neck 58. The guard 22 includes a collar 70 coupled to the neck 58 and a plurality of radially inward-extending tabs 74 on the interior of the collar 70. The guard 22 also includes a shroud 82 that partially surrounds the grinding disk 26 (FIG. 2) to protect the user from debris generated during operation. The tabs 74 on the collar 70 may have different sizes and/or shapes that must first be aligned with corresponding gaps defined between the tabs 74 on the neck 58, such that the guard 22 is attachable to the neck 58, and removable therefrom, in only a single orientation.
With reference to FIGS. 1-3, the angle grinder 10 also includes a locking mechanism 86 to secure the guard 22 in a plurality of discrete orientations relative to the spindle housing 18. With reference to FIG. 4, the locking mechanism 86 includes a lever 90, a plurality of springs 94 biasing the lever 90 toward a locking state with the guard 22, and a plurality of recesses 98 defined in the guard 22 in an arcuate array between adjacent protrusions 100 on the guard 22 extending toward the cover portion 38. The lever 90 includes opposite, first and second actuation portions 102A, 102B that are alternately pressed by the to release the lever 90 from the locking position. As shown in FIG. 4, the actuation portions 102A, 102B are located on opposite sides of the spindle housing 18. The lever 90 also includes a detent 106 centrally located between the actuation portions 102A, 102B that is shaped to fit within any of the recesses 98 in the guard 22. When the detent 106 is inserted into one of the recesses 98 in the locking state of the locking mechanism 86, the guard 22 rotationally locked and is rotationally immovable about the axis A1 and cannot be rotated relative to the spindle housing 18. The lever 90 further includes an arcuate slot 110 and a L-shaped slot 114, which direct the motion of the lever 90 when actuated. The arcuate slot 110 is arcuately shaped and can receive a fastener 119 to secure the lever 90 to the spindle housing 18. The L-shaped slot 114 includes a vertical segment 116 and a horizontal segment 118 and can also receive a fastener 119 to secure the lever 90 to spindle housing 18. Each fastener is inserted into a respective hole 120 in the spindle housing 18 (only one of which is shown in FIG. 3), which define a set of parallel axes A2 and A3. The fasteners 119 are anchored in the motor housing 14 to thereby secure the lever 90 to the spindle housing 18 and the motor housing 14. A set of spring perches 92 is formed on the lever 90 and serve to retain one end of the springs 94 on the lever 90, whereas the opposite ends of the springs 94 are received in respective pockets in the cover portion 38.
In operation, the user can engage the first actuation portion 102A or the second actuation portion 102B to transition the locking mechanism 86 from the locking state to the release state. Normally, the lever 90 begins in the locking state, as shown in FIG. 5A, where the detent 106 is engaged with one of the recesses 98, depending upon the orientation of the guard 22. If the user presses the first actuation portion 102A, the lever 90 rotates about axis A2, as shown in the transition of the locking mechanism 86 from the locking state in FIG. 5A to one instance of the release state in FIG. 5B. In this scenario, the fastener 119 aligned with axis A2 remains stationary within the arcuate slot 110, whereas the fastener 119 aligned with axis A3 moves from one end of the vertical segment 116 to the other end of the vertical segment 116. In the release state, the guard 22 can be rotationally adjusted about axis A1 (FIG. 3) to the user's preference. After the guard 22 is adjusted to the desired orientation, the first actuation portion 102A is released and the springs 94 rebound from a compressed state to return the lever 90 to the locking state shown in FIG. 5A.
In another scenario, the user may instead press the second actuation portion 102B to transition the locking mechanism 86 from the locking state in FIG. 5A to the release state in FIG. 5C. When the second actuation portion 102B is pressed, the fastener 119 aligned with axis A2 slides within the arcuate slot 110 from one end to the other, causing the lever 90 to pivot about axis A3. Simultaneously, the lever 90 translates in a lateral direction as the fastener 119 aligned with axis A3 translates from one end of the horizontal segment 118 of the L-shaped slot 114 to the other, as shown in the transition from FIG. 5A to FIG. 5C. As such, when the second actuation portion 102B is depressed, the lever 90 experiences two degrees of freedom (i.e., pivoting and translation) when transitioning from the locking state to the release state, whereas when the first actuation portion 102A is depressed, the lever 90 experiences only a single degree of freedom (i.e., pivoting). Once the user finishes adjusting the guard 22, the user releases the second actuation portion 102B and the springs 94 rebound from a compressed state to return the lever 90 to the locking state. As such, depending on which actuation portion 102A, 102B is pressed, the springs 94 are individually compressible.
To install the guard 22, the user must align the tabs 74 on the collar 70 with the corresponding gaps defined between the tabs 66 on the neck 58. Next, the user moves the locking mechanism 86 into a release state to allow for the guard 22 to be rotated around the rotation axis A1 to position the shroud 82 in an optimal blocking direction. Once positioned, the user can engage the detent 106 of the lever 90 with the plurality of recesses 98 to prevent rotational movement of the guard 22. To remove the guard 22, the user must disengage the locking mechanism 86 and rotate the guard 22 until every tab 74 of the collar 70 matches up with the gaps created by the tabs 66 on the neck 58. Once the tabs 74 are aligned with the gaps, the user can pull the guard 22 outwards along the axis A1 and away from the spindle housing 18.
Another embodiment of a locking mechanism 1086 for use with the angle grinder 10 of FIG. 1 is shown in FIG. 6. The locking mechanism 1086 includes a central lock body or detent 1106, a first actuator 1102A, a second actuator 1102B, and a detent spring 1194, and a set of actuator springs 1196. The detent 1106 engages the recesses 98 in the guard 22. The first actuator 1102A engages a first surface 1122 of the detent 1106. The second actuator 1102B engages a second surface 1126 of the detent 1106. The detent 1106 includes a first guide slot 1110A and a set of posts 1112 to restrict movement of the detent 1106 along the detent axis A4. The first slot 1110A also receives a fastener (not shown) to and mount the detent 1106 onto the spindle housing 18 and to limit the axial movement of the detent 1106 along detent axis A4 to the length of the slot 1110A. Likewise, the first and second actuators 1102A, 1102B include a second guide slot 1110B to restrict the movement of each of the actuators 1102A, 1102B along an axis A5 and the length of the slots 1110B, and to mount the actuators 1102A, 1102B to the spindle housing 18. Additionally, the first guide slot 1110A is orientated transversely to second guide slots 1110B. The detent 1106, the first actuator 1102A, and the second actuator 1102B each include a spring perch 1192, which retains the corresponding springs 1194, 1196. The detent spring 1194 biases the detent 1106 into engagement with the guard 22 (the locking state), while the actuator springs bias the first and second actuator 1102A, 1102B away from the detent 1106.
Normally, the locking mechanism 1086 is in a locking state, where the detent 1106 is engaged with the recesses 98 in the guard 22 to prevent rotation. To transition to the release state, the user can push the first actuator 1102A and/or the second actuator 1102B along the second guide slots 1110B towards the first surface 1122 and/or the second surface 1126. The first and second surfaces 1122, 1126 are obliquely orientated with respect to detent axis A4 and correspond to an actuation surface 1104 on both actuators 1102A, 1102B. When the first or second actuator 1102A, 1102B are pressed, the actuation surfaces 1104 contact and slide along the first or second surfaces 1122 of the detent 1106 to retract the detent 1106 along detent axis A4. As a result, the locking mechanism 1086 is transitioned into the release state, where the user can rotate the guard 22 to a new desired orientation. When the new desired orientation is reached, the user releases the first and/or second actuators 1102A, 1102B, and the detent spring 1194 biases the detent 1106 back into engagement with the recesses 98 to prevent rotation of the guard 22. Simultaneously, the actuator springs 1196 move the first and second actuators 1102A, 1102B away from the detent 1106 along axis A5.
Another embodiment of a locking mechanism 2086 is shown in FIG. 7. The locking mechanism includes a lever 2090 that engages a notch 2134 in a guard 2022. The lever 2090 is pivotably mounted to the spindle housing 18 via a fastener (not shown). The fastener is inserted into a through hole 2130, which also defines a lever axis A6 that is parallel to the rotational axis A1. The lever 2090 includes a tab 2102, a detent 2106, and a spring (not shown). The tab 2102 is located on one end of the lever 2090 and allows a user to rotate the lever 2090 around the lever axis A6. The detent 2106 is located on an opposing end of the lever 2090, and selectively engages one of the notches 2134 in the guard 2022. The spring biases the detent 2106 towards the notches 2134.
In operation, the user engages the tab 2102 to rotate the lever 2090 along lever axis A6, so the detent 2106 moves away from the guard 2022. When the detent 2106 is not engaged with one of the notches 2134, the locking mechanism 2086 is in the release state, where the user is free to rotate the guard 2022 to a new desired orientation. When the new desired orientation is reached, the user can release the tab 2102 and the spring biases the detent 2106 back towards the guard 2022. The detent 2106 is inserted into one of the notches 2134 and the guard 2022 is in the locked state, where it can no longer be rotated or adjusted. In some embodiments, the spring may be removed, and the user would manually rotate the lever 2090 to the locked state.
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 as described.
Various features of the invention are set forth in the following claims.
Patent Application
20240326197
