Patent Application
20210282597
The present disclosure relates generally to stand mixers, and in particular with self-scraping mixers.
A stand mixer is a device used in many home and commercial kitchens to mix ingredients for cooking, baking, etc. The mixer has a base, with a cradle configured to securely hold a mixing bowl. A vertical post is coupled to the base and supports an arm that is cantilevered over the bowl, with one or more motor-driven mixing elements extending from the arm down into the bowl, with the motor typically housed in the arm. The bowl can be motor-driven to rotate as the mixing element(s) rotate in place, or the mixing elements can be configured to operate in a planetary motion, in which the elements rotate about respective axes, while the axes rotate about a central axis, etc. The mixing elements are often interchangeable, with different kinds of elements used for different mixing tasks, and/or for light, medium, or heavy duty. Examples of different mixing elements include wire whip, whisk, flat beater, dough hook, etc.
According to an embodiment, a stand mixer is provided, which includes a mixing bowl and one or more beaters configured to rotate within the bowl and orbit about a common axis that is concentric with the bowl. The mixer further includes a scraper with an edge that is shaped to conform to an inside wall of the bowl, and which is also configured to orbit, with the beaters, about the common axis, while rotating at the same rate so that the edge of the scraper remains in contact with the inner wall of the bowl.
According to an embodiment, a stand mixer is provided, including a bowl cradle configured to hold a circular mixing bowl, and a drive mechanism. The drive mechanism includes a first socket and a second socket, and is configured to rotate the first socket and to orbit the first and second sockets relative to a bowl held by the bowl cradle. The drive mechanism is further configured to hold the second socket such that the second socket rotates synchronously.
According to an embodiment, a method for operating a stand mixer is provided. The method includes coupling a beater to a drive mechanism of the stand mixer, coupling a scraper to the drive mechanism, engaging a mixing bowl to a cradle of the stand mixer, and mixing the contents of the mixing bowl. This is accomplished by rotating the beater while orbiting the beater relative to a central axis of the mixing bowl. The method further includes scraping the side of the mixing bowl by orbiting the scraper relative to the central axis of the mixing bowl while synchronously rotating the scraper.
In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. Other embodiments may be used and/or other changes may be made without departing from the spirit or scope of the disclosure.
As used hereafter and in the claims, the term beater refers broadly to any type of mixing element component, including, for example, whisks, flat beaters, dough hooks, etc., except where the term is otherwise explicitly defined.
In
The bowl scraper 118 is also configured to orbit with the mixing element 110 about the second axis of rotation AR3. However, in contrast to the beaters 111 of the mixing element 110, the scraper does not also rotate about another axis, but is fixed, so as to continually present a same, or fixed aspect, relative to the central axis of rotation AR3. The shape of the scraper 118 is selected so as to remain in contact with an inner surface of the mixing bowl 108. Accordingly, as the mixing element 110 orbits within the bowl 108, mixing the contents, the scraper 118 also orbits within the bowl, cleaning the side of the bowl and moving material from the side of the bowl toward the center.
According to an embodiment, the blade 120 of the bowl scraper 118 is made of nylon, and is substantially rigid, which enables the scraper to move even heavy masses of batter or dough without significantly deforming. According to another embodiment, the blade 120 is made of an elastomeric material, such as, e.g., urethane, silicone, synthetic or natural rubber, etc., and is configured to be positioned so as to flex slightly against the wall of the mixing bowl 108 and provide a seal against the bowl to effectively clean the bowl as it passes. According to a further embodiment, the blade 120 includes a reinforced or stiffened body so as to resist deformation, with a scraping edge 122 that is of an elastomeric material configured to flex slightly against the wall of the mixing bowl 108.
The drive, transmission, and output gears 132, 134, 136 of the drive mechanism 130 are journaled or otherwise rotatably coupled to the drive plate 140. Arrows indicating directions of rotation are provided to show relative directions of rotation of the various elements, i.e., if the drive gear 132 rotates clockwise, as shown in
The mixing beaters 111 each include a coupler 142 configured to engage a corresponding beater socket 144 of a respective one of the output gears 136, so that the beaters rotate with the respective output gears. The handle 128 of the scraper 118 also includes a coupler 146 (see, also,
Because they are rotatably coupled to the drive plate 140, the transmission and output gears 134, 136 orbit with the drive plate about the central axis of rotation AR3, even as they each rotate about their own respective axes of rotation. Thus, as the beaters 111 counter rotate relative to each other, they also rotate, or orbit, about the center of the mixing bowl 108. For its part, the scraper 118 orbits with the beaters 111 about the center of the mixing bowl 108. However, the scraper 118 does not also rotate with respect to the drive plate 140. As noted above, the scraper socket 148 is fixed to the drive plate 140. Thus, the scraper 118 is held so as to continually present a same aspect to the central axis of rotation AR3. In other words, the scraper 118 rotates about its own axis once each time it orbits the central axis of rotation AR3, so that its rotational period is equal to its orbital period. The term synchronous rotation will be used hereafter to describe this motion. During operation, with the scraper 118 in synchronous rotation about the central axis of rotation AR3, the blade 120 remains in continuous contact with the inner surface of the bowl 108 as it rotates, moving material from the side of the bowl back into reach of the beaters.
The drive mechanism 130 is shown as one example, but embodiments are contemplated that include different types and configurations of drive mechanisms that are equivalent, and that perform the actions described above with reference to the drive mechanism 130. Furthermore, according to various embodiments, the mechanism shown is modified to meet specific design parameters. For example, relative sizes of the drive, transmission, output, and ring gears 132, 134, 136, 138 can be changed to obtain different relative rates of orbit and rotation, to provide appropriate orbit and rotation rates for mixers of different sizes and purposes, and having single or multiple beaters 111, single or multiple scrapers 118, etc. Design of the variations and alternatives to the drive mechanism 130 discussed above are within the abilities of a person having ordinary skill in the art, and so will not be described in detail.
In the embodiment shown, the output gears 136 are configured to counter-rotate. According to another embodiment, a drive mechanism is provided that is configured to rotate multiple beaters in a same direction—the beaters being sized and positioned such that they do not intermesh.
According to an embodiment, a stand mixer is provided that includes a cradle configured to rotate the bowl 108 during operation. The mixing element 110 includes one or more beaters 111 that are configured to rotate about respective axes of rotation, and a bowl scraper 118 is provided that is configured to conform to the shape of the bowl. However, neither the scraper 118 nor the mixing element 110 are configured to orbit about a common axis. Instead, the equivalent function is provided by rotation of the bowl 108 about its own central axis, which causes the positions of the mixing element 110 and the scraper 118 to orbit relative to the bowl, with the scraper cleaning the side of the bowl as the bowl rotates thereunder, substantially as previously described. Accordingly, claims that recite orbit of a scraper and/or one or more beaters relative to a bowl read also on embodiments in which the bowl rotates instead of, or in addition to the scraper(s) and beater(s).
The inventor has recognized a problem associated with typical stand mixers such as are known in the art: even with stand mixers in which beaters are configured to conform closely to the shape of the mixing bowl, there will usually be at least a small clearance between the blades or tines of a beater and the walls of the bowl, so that some of the material in the bowl will inevitably be deposited on the walls, and out of reach of the beaters. In mixers designed for use by consumers, this may not be a significant problem, as a small mixer can be easily stopped periodically to permit the user to scrape the side of the bowl. However, this is a bigger problem in large commercial and industrial mixers, inasmuch as it can take some time to start and completely stop such mixers, and time spent starting and stopping the mixer and scraping the side of the bowl increases production time and costs, and can also change the characteristics of the mixture. On the other hand, if the side is not scraped, some portion of the contents may not be fully mixed, which can change the ratio of ingredients in a mix, reduce the volume of the final mixture, increase waste of ingredients, and increase the per-unit cost of the final product. If a user is tempted to reduce down time by scraping the side without stopping the mixer, this can increase the likelihood of injury to the user and/or damage to the mixer. In contrast, in accordance with various embodiments, a user can operate a stand mixer with efficiency and economy without risking damage to the mixer or injury to the user.
In the embodiment shown, the bowl 108 has an approximately square profile, which is not well swept by the beaters 111, particularly the portion of the bowl where the side meet the bottom. Therefore, according to an embodiment, the scraper 201 is also shaped to scrape into the corner and across a portion of the bottom of the bowl 108, in order to prevent material from sticking to the bottom, outside the sweep of the beaters. According to another embodiment, the scraper is configured to scrape the side of the bowl, only.
In operation, a user rolls the bowl 108 into position between the legs 194, with the engagement brackets 204 engaging respective connectors 206, as shown in
Upon completion of the mixing process, the motor is disengaged, and the user operates the power lift mechanism to lower the bowl 108 until the casters 202 again contact the floor. The bowl 108 can then be moved to another location or its contents accessed from its current position, as necessary.
Because of the operation of the bowl scraper 201, it is not necessary to pause operation of the mixer 190 to scrape down the side of the bowl 108. This can save considerable time and increase productivity, particularly in the operation of large mixers. The throughput of the mixer can be significantly greater than with conventional mixers, and in some case may permit the use of a smaller, lower capacity—and lower cost—mixer, or, in operations that employ multiple mixers, may reduce the number of mixers required, to meet a particular production requirement.
In the specification and claims, the term orbit is used to refer to rotation of an element about an axis that lies outside of that element. The term handle is used to refer to a portion of a scraper that extends between a coupler at one end and a scraper blade at the other end. The handle is not necessarily configured to be comfortably held in the hand of a user.
In many of the drawings, elements are designated with a reference number followed by a letter, e.g., 182a, or 182b. In such cases, the letter designation is used where it may be useful in the corresponding description to differentiate between or to refer to specific ones of a number of otherwise similar or identical elements. Where the description omits the letter from a reference, and refers to such elements by number only, this can be understood as a general reference to any or all of the elements identified by that reference number, unless other distinguishing language is used.
Ordinal numbers, e.g., first, second, third, etc., are used in the claims according to conventional claim practice, i.e., for the purpose of clearly distinguishing between claimed elements or features thereof, etc., without imposing further limitations on those elements. Ordinal numbers may be assigned arbitrarily, or assigned simply in the order in which elements are introduced. The use of such numbers does not suggest any other relationship, such as order of operation, relative position of such elements, etc. Furthermore, an ordinal number used to refer to an element in a claim should not be assumed to correlate to a number used in the specification to refer to an element of a disclosed embodiment on which that claim reads, nor to numbers used in unrelated claims to designate similar elements or features.
The abstract of the present disclosure is provided as a brief outline of some of the principles of the invention according to one embodiment, and is not intended as a complete or definitive description of any embodiment thereof, nor should it be relied upon to define terms used in the specification or claims. The abstract does not limit the scope of the claims.
Elements of the various embodiments described above can be omitted or combined to provide further embodiments. Aspects of the embodiments can be modified to employ concepts of known art to provide yet further embodiments.
These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification, but should be construed to include all possible embodiments along with the full scope of equivalents to which such claims are entitled. Accordingly, the claims are not limited by the disclosure.
This application claims the benefit of Provisional Patent Application Ser. No. 62/792,331, filed Jan. 14, 2019, which application is incorporated herein by reference in its entirety.
