FINE DETAIL SANDER

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application No. 63/729,655 filed on December 9, 2024, the entire content of which is incorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates to power tools and more particularly to powered sanders.

BACKGROUND OF THE INVENTION

Most battery powered sanders utilize an electric motor that provides a rotational output to drive a sanding accessory. The size of the electric motor limits how small the sander can be and therefore restricts where the sander can be used.

SUMMARY OF THE INVENTION

The present invention provides, in one aspect, a sander including a housing having a grip portion and a battery receptacle portion extending rearwardly therefrom and a chuck extending from the grip portion of the housing and movable relative to the housing in at least a first degree of freedom. The chuck is configured to receive a sanding accessory for performing a sanding operation on a workpiece in response to movement of the chuck. The sander also includes an electromagnet within the grip portion of the housing, an actuator having a first end coupled to the chuck and a second end with ferrous metal responsive to a magnetic field created by the electromagnet, and an electronic control unit configured to receive electrical current from a battery received in the battery receptacle portion of the housing and supply electrical current to the electromagnet to create the magnetic field. The electronic control unit is configured to fluctuate the magnetic field, imparting movement to the actuator and the chuck in at least the first degree of freedom.

The present invention provides, in another aspect, a sander comprising a housing including a grip portion and a battery receptacle portion extending rearwardly therefrom, a chuck extending from the grip portion of the housing and movable relative to the housing in at least a first degree of freedom, the chuck configured to receive a sanding accessory for performing a sanding operation on a workpiece in response to movement of the chuck, an electromagnet within the housing, an actuator having a first end coupled to the chuck and a second end with ferrous metal responsive to a magnetic field created by the electromagnet, a trigger including an onboard lockout member proximate the grip portion and configured to selectively activate the electromagnet; and an electronic control unit configured to receive electrical current from a battery received in the battery receptacle portion of the housing and supply electrical current to the electromagnet to create the magnetic field wherein the electronic control unit is configured to fluctuate the magnetic field, imparting movement to the actuator and the chuck in at least the first degree of freedom.

The present invention provides, in another aspect, a sander comprising a housing including a grip portion and a battery receptacle portion extending rearwardly therefrom, a chuck extending from the grip portion of the housing and movable relative to the housing in at least a first degree of freedom, the chuck configured to receive a sanding accessory for performing a sanding operation on a workpiece in response to movement of the chuck, a battery received in the battery receptacle portion, an electromagnet within the grip portion of the housing, a frusto-conical actuator having a first end coupled to the chuck and a second end with ferrous metal responsive to a magnetic field created by the electromagnet, and an electronic control unit configured to transmit electrical current from the battery to the electromagnet to create the magnetic field.

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

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of a sander in accordance with an embodiment of the invention.

Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure 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 disclosure 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

With reference to FIG. 1, a powered sanding tool 10 or sander is shown. The sander includes a housing 14 having a grip portion 18 and an adjacent, rearward battery receptacle portion 22 in which a battery 24 is received. In some embodiments, the battery receptacle portion 22 is at least partially defined by a cover 30 that is removably coupled to the remainder of the housing 14 to provide access to the battery receptacle portion 22 to remove the battery 24 therefrom. In other embodiments, the battery 24 may be permanently enclosed within the battery receptacle portion 22 and rechargeable via a charging terminal (not shown) accessible from the exterior of the housing 14. In both embodiments, the grip portion 18 and the battery receptacle portion 22 are coaxial with a central axis.

The sander also includes a chuck 34 extending forwardly from the grip portion 18 of the housing 14. The chuck 34 is movable relative to the housing 14 in at least a first degree of freedom. In the illustrated embodiment, the housing 14 includes a channel 38 in which a flange 42 on the chuck 34 is loosely received to permit the chuck 34 to move in at least a first degree of freedom, that is, translate along the central axis a limited amount (i.e., vibrate), oscillate about the central axis, rotate about the central axis, or any combination thereof.

The chuck 34 also includes a non-cylindrical (e.g., hexagonal) axial bore 43 on an opposite end 46 as the flange 42 in which a sanding accessory 50 for performing a sanding operation is received. In some embodiments, the chuck 34 includes a quick-release mechanism 54 to selectively retain the sanding tool 50 within the axial bore 43 during a sanding operation. The illustrated quick-release mechanism 54 includes opposed ball detents 60 received in radial bores 64, respectively, having inward ends exposed to the axial bore 43 such that at least a portion of each of the ball detents 60 can protrude into the axial bore 43. The quick-release mechanism 54 also includes a compression spring 68 captured inside each of the radial bore 64s for biasing the ball detents 60 in a radially inward direction. As shown in FIG. 1, the sanding accessory 50 includes a non-cylindrical (e.g., hexagonal) shank 72 that is received in the axial bore 43. The shank 72 includes a circumferential groove 76 in which the ball detents 60 are receivable to retain the shank 72 within the axial bore 43 during a sanding operation. To remove the sanding accessory 50, a removal force is applied to the shank 72 with a sufficiently high magnitude to overcome the bias of the springs 68 acting on the ball detents 60.

With continued reference to FIG. 1, the sander 10 includes an electromagnet 80 within the grip portion 18 of the housing 14 and an electronic control unit 84 operable to selectively energize the electromagnet 80. The electromagnetic 80 can be made from Ferrite, Neodymium, or Alnico, for example. The electronic control unit 84 is electrically connected to the electromagnet 80 and the battery 24 with electrical wires, which supply electrical current from the battery 24 to the electromagnet 80 to create a magnetic field. The electronic control unit 84 is also operable to control the strength and direction of the magnetic field by controlling the magnitude and the direction of the electrical current supplied to the electromagnet 80.

The sander 10 also includes a trigger 88 on the grip portion 18 of the housing 14 that is operable to selectively electrically connect the battery 24 to the electromagnet 80 (via the electronic control unit 84 as described above) to activate the electromagnet 80. In one embodiment, the trigger 88 may be configured as a pivotable paddle optionally including an onboard lockout member 90. In another embodiment, the trigger 88 may be configured as a slidable thumb switch or slidable shuttle that moves along the length of the grip portion of the housing from a first, “off” position to a second, “on” position.

The sander 10 further includes an actuator 92 having a first end 96 that is coupled to the chuck 34 and a second end 100 with ferrous metal. The magnetic properties of the ferrous metal make the second end 100 of the actuator 92 responsive to the magnetic field created by the electromagnet 80, where fluctuations in the magnetic field can be caused by the electronic control unit 84 to impart movement to the actuator 92 and therefore the attached chuck 34. As described above, the electronic control unit 84 can alter or fluctuate the magnetic field, which is able to impart different effects on the actuator 92. In the illustrated embodiment, the second end 100 of the actuator 92 is responsive to the fluctuating magnetic field to impart movement to the chuck 34 in at least the first degree of freedom, such as vibration (i.e., reciprocating translation) along the central axis. To accomplish this, the electronic control unit 84 can alternate the direction of the electrical current supplied to the electromagnet 80, which alternates the polarities of the magnetic field and thus alternately attracts and repels the second end 100 of the actuator 92. The electronic control unit 84 can also adjust a frequency of vibration transmitted to the chuck 34 by alternating the polarities of the magnetic field at different rates (i.e., frequencies). Such an adjustment in the vibration frequency of the chuck 34 may be accomplished by a variable speed switch 89 that is actuated by the trigger 88, for example, to increase the vibration frequency in direct proportion to further movement of the trigger 88 from the “off” position to the “on” position.

The actuator 92 can be made from a wide range of materials including but not limited to plastics, metals, paper, carbon fiber, acrylic coated cloth, aramid fibers such as aromatic polyamide and copolyamide. In one embodiment, the actuator 92 is frusto-conical (i.e., having a cone shape), with the first end 96 having a larger diameter and the second end 100 having a smaller diameter. In some embodiments, the sander 10 includes a support structure 104 positioned between the first and second ends 96, 100 of the actuator 92. The support structure 104 aligns the actuator 92 with the grip portion 18 of the housing 14 so they both are coaxial. The actuator 92 can be elastic to return the actuator 92 to its original position and/or shape when the magnetic field dissipates. The support structure 104 can be manufactured as part of the actuator 92 so the support structure 104 and the actuator 92 are a single piece or a separate element that is coupled to the actuator 92 during assembly. In some embodiments, the support structure 104 dictates the maximum amount of movement in the first degree of freedom, therefore functioning as a mechanical stop past which the actuator 92 cannot move.

In operation of the sander 10 with the attached sanding accessory 50, the user energizes the electromagnet 80 by moving the trigger 88 to the “on” position, thus causing the chuck 34 and sanding accessory 50 to begin moving in the at least first degree of freedom at a predetermined frequency. In one embodiment, the movement can be a user-determined frequency based on the extent of the trigger’s 88 movement, where the trigger 88 is a variable speed trigger.

Although the disclosure 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 disclosure as described.

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