COIL ARRANGEMENTS FOR METAL DETECTION IN UNDER-SINK DISPOSAL UNITS

Abstract

An under-sink disposal unit includes a motor, a disposal chamber, and a passageway that extends from an opening in a top of the disposal unit to a grinding area of the disposal chamber. The disposal unit further includes a coil assembly comprising an arrangement of coils. The arrangement of coils is used to detect the passing of a metallic object in the passageway toward the grinding area of the disposal unit. The arrangement of coils comprises four pairs of coils, wherein each pair of coils comprises a transmit coil and a receive coil. The four pair of coils are arranged around an axis of the passageway and are offset relative thereto. Transmit coils located along a common axis are wound in the same direction such that the magnetic fields generated thereby augment the filed for detecting metallic objects passing toward the grinding area.

Claims

1. An under-sink disposal unit, comprising a motor, a disposal chamber, and a passageway that extends from an opening in a top of the disposal unit to a grinding area of the disposal chamber, and further comprising (a) a coil assembly comprising an arrangement of coils, (b) wherein the arrangement of coils is used to detect the passing of a metallic object in the passageway when passing from the opening in the top of the disposal unit to the grinding area, and (c) wherein the arrangement of coils comprises a plurality of coils including two or more transmit coils and two or more receive coils, wherein: the transmit coils are electrically coupled and the receive coils are not electrically coupled; and each transmit coil comprises a plurality of loops (i.e., windings) which are all in the same direction.

2. The under-sink disposal unit of claim 1, wherein the transmit coils are approximately the same shape and size.

3. The under-sink disposal unit of claim 1, wherein the transmit coils are identical.

4. The under-sink disposal unit of claim 1, wherein each coil is oriented with respect to an axis of the passageway such that objects passing through the passageway toward the disposal chamber pass by and proximate to, but do not pass through, the loop of the coil.

5. The under-sink disposal unit of claim 1, wherein each coil in the disposal unit is oriented such that, with respect to an axis of the passageway, an object passing through the passageway toward the disposal chamber does not pass through any loop of such coil.

6. An under-sink disposal unit, comprising a motor, a disposal chamber, and a passageway that extends from an opening in a top of the disposal unit to a grinding area of the disposal chamber, and further comprising (a) a coil assembly comprising an arrangement of coils, (b) wherein the arrangement of coils is used to detect the passing of a metallic object in the passageway when passing from the opening in the top of the disposal unit to the grinding area, and (c) wherein the arrangement of coils comprises two coils that are offset from an axis of the passageway insofar as the center points of the coils are not equidistant from the axis of the passageway.

7. The under-sink disposal unit of claim 6, wherein the two offset coils are transmit coils.

8. The under-sink disposal unit of claim 6, wherein the two offset coils are receive coils.

9. An under-sink disposal unit, comprising a motor, a disposal chamber, and a passageway that extends from an opening in a top of the disposal unit to a grinding area of the disposal chamber, and further comprising (a) a coil assembly comprising an arrangement of coils, (b) wherein the arrangement of coils is used to detect the passing of a metallic object in the passageway when passing from the opening in the top of the disposal unit to the grinding area, and (c) wherein the arrangement of coils comprises two pairs of coilseach pair comprising a receive coil and a transmit coilwherein the two pairs of coils are offset from an axis of the passageway insofar as the center points of the two pairs of coils are not equidistant from the axis of the passageway.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] One or more preferred embodiments of the present invention now will be described in detail with reference to the accompanying drawings, wherein the same elements are referred to with the same reference numerals, and wherein:

[0023] FIG. 1 is a perspective view of a disposal unit.

[0024] FIG. 1A is a shaded view of FIG. 1.

[0025] FIG. 2 is a perspective view of the disposal unit of FIG. 1 in which some components are omitted for clarity of illustration.

[0026] FIG. 2A is a shaded view of FIG. 2.

[0027] FIG. 3 is a perspective view of the disposal unit of FIG. 2 in which some additional components are omitted for clarity of illustration.

[0028] FIG. 3A is a shaded view of FIG. 3.

[0029] FIG. 4 is a schematic illustration of a coil arrangement of the disposal unit of FIG. 1.

[0030] FIG. 5 is a schematic illustration of an alternative coil arrangement of the disposal unit of FIG. 1.

[0031] FIG. 6 is a schematic illustration of another alternative coil arrangement of the disposal unit of FIG. 1.

DETAILED DESCRIPTION

[0032] FIG. 1 is a perspective view of a disposal unit 100, and FIG. 1A is a shaded view of the disposal unit 100. Similarly, FIG. 2 is a perspective view of the disposal unit 100 of FIG. 1 in which some components are omitted for clarity of illustration, and FIG. 2A is a shaded view thereof; FIG. 3 is a perspective view of the disposal unit 100 of FIG. 2 in which some additional components are omitted for clarity of illustration, and FIG. 3A is a shaded view thereof.

[0033] The disposal unit 100 is representative of major components of disposal units used in various preferred embodiments of the invention. As shown in FIGS. 1 and 2, components of the disposal unit 100 include a disposal body 102, a tailpipe 104, a disposal body flange 106, a mounting ring 108, a backup ring 110, and a mounting gasket 112. As shown in FIG. 3, components used in shredding of waste in a shredding area of a disposal chamber during operation of the disposal unit 100 include a body axle 114, grinding tooth 116, grinding tooth 118, and end frame 120. Preferred embodiments of aspects and features of the invention are now described in detail within the context of components of disposal units as represented by disposal unit 100.

[0034] As will be appreciated, the disposal includes a passageway that extends from an opening in a top of the disposal unit to a grinding area of the disposal chamber. The body axle 114 extends along an axis z of this passageway. The disposal unit 100 further includes a coil assembly comprising an arrangement of coils. The arrangement of coils is used to detect the passing of a metallic object toward the grinding area of the disposal unit.

[0035] As seen in FIGS. 1-4, the arrangement of coils comprises a plurality of coils including two or more transmit coils and two or more receive coils. Specifically, the arrangement of coils in FIGS. 1-4 comprises four pair of coils. Each pair comprises a transmit coil and a receive coil, and two pairs are opposed on the x axis and two pairs are opposed along the y axis. These coils are shown in phantom in FIGS. 1-2A, and are shown relative to the orthogonal axes x,y,z in FIG. 4.

[0036] With particular regard to FIG. 4, the arrangement of the coil pairs relative to the axis z is seen to be equidistance, insofar as each coil pair is located from the axis z the same distance within the x-y plane. Furthermore, each coil pair is oriented with respect to the z axis such that objects passing through the passageway toward the disposal chamber in the disposal unit pass by and proximate to, but do not pass through, any loop of any of the coils in the arrangement.

[0037] Furthermore, as perhaps best seen here, each transmit coil and receive coil comprises a plurality of loops or windings. Preferably, each coil comprises between 2 and 50 loops or windings. Additionally, the transmit coils are approximately the same shape and size, and preferably the transmit coils are identical. The receive coils also are approximately the same shape and size, and preferably the receive coils are identical.

[0038] As further seen in FIG. 4, the transmit coils along the x axis are electrically coupled and the corresponding receive coils are not electrically coupled; and the transmit coils along the y axis are electrically coupled and the corresponding receive coils are not electrically coupled.

[0039] Additionally, the transmit coils are located on opposite sides of the z axis, and each transmit coil along an axis (i.e., the x axis or the y axis) preferably is formed by windings that extend in the same direction, whereby the magnetic fields created by the transmit coils along the axis are augmented. In this respect, the transmit coils are electrically coupled so as to be in phase. The electrical coupling of the transmit coils preferably is accomplished by using a single, electrically conductive wire to form all of the transmit coils that are located along a common axis.

[0040] With further respect to the coil pairs of the coil arrangement, each receive coil is located with a corresponding transmit coil, with the corresponding transmit coil bounding at least an upper portion and a lower portion of the receive coil and, as illustrated, bounding the entirety of the receive coil.

[0041] FIG. 5 illustrates an alternative coil arrangement. This coil arrangement is similar to that of FIG. 4, with the exception that the opposed coil pairs along they axis are offset relative to the origin or z axis, with one coil pair on the y axis being further from the origin or z axis than the other coil pair on the y axis. In other words, the coil pairs are offset insofar as the center points of the transmit coils along the y axis are not equidistant from the z axis, and the center points of the receive coils along the y axis are not equidistant from the z axis. This shift along the y axis is believed to shift the field characteristics along the y axis.

[0042] Likewise, while not show, another alternative coil arrangement is similar to that of FIG. 4, with the exception that the opposed coil pairs along the x axis are offset relative to the origin or z axis, with one coil pair on the x axis being further from the origin or z axis than the other coil pair on the x axis. In other words, the coil pairs are offset insofar as the center points of the transmit coils along the x axis are not equidistant from the z axis, and the center points of the receive coils along the x axis are not equidistant from the z axis. This shift along the x axis is believed to shift the field characteristics along the x axis.

[0043] FIG. 6 illustrates still yet another alternative coil arrangement. This coil arrangement is similar to the arrangement of coils seen in FIG. 4, with the exceptions that the opposed coil pairs along the y axis are offset relative to the origin or z axis, with one coil pair on the y axis being further from the origin or z axis than the other coil pair on the y axis; and that the opposed coil pairs along the x axis are offset relative to the origin or z axis, with one coil pair on the x axis being further from the origin or z axis than the other coil pair on the x axis. In other words, the coil pairs along the y axis are offset insofar as the center points of the transmit coils along the y axis are not equidistant from the z axis, and the center points of the receive coils along the y axis are not equidistant from the z axis; and the coil pairs along the x axis are offset insofar as the center points of the transmit coils along the x axis are not equidistant from the z axis, and the center points of the receive coils along the x axis are not equidistant from the z axis. This shift along the x axis is believed to shift the field characteristics along the x axis. This shift along the y axis is believed to shift the field characteristics along the y axis.

[0044] The aforementioned offsetting is believed to move areas of field cancelation away from z axis, i.e., the axis of the passageway through the disposal unit, resulting in an increase in the sensitivity of the detection of a metallic object passing toward the grinding area of the disposal unit. Indeed, it is currently believed that the coil arrangement of FIG. 4 may have a dead spot or otherwise significant drop in sensitivity in detection at the origin, i.e., intersection, of the illustrated axes. Shifting of this possible dead spot is believed to increase the performance and detection of metallic objects, which are believed to more likely fall along the center of the passageway, i.e., the z axis, than along a side of the passageway.

[0045] Based on the foregoing description, it will be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those specifically described herein, as well as many variations, modifications, and equivalent arrangements, will be apparent from or reasonably suggested by the present invention and the foregoing descriptions thereof, without departing from the substance or scope of the present invention. For instance, while preferred embodiments have been described within the context of residential use, it is believed that the present invention has applicability to use with commercial disposal units as well.

[0046] Accordingly, while the present invention has been described herein in detail in relation to one or more preferred embodiments, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for the purpose of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended to be construed to limit the present invention or otherwise exclude any such other embodiments, adaptations, variations, modifications or equivalent arrangements, the present invention being limited only by the claims appended hereto and the equivalents thereof.