Atomising device for coating apparatus

ES 2 302 734 T3

DESCRIPTION

Atomizing device for coating apparatus.

Field of the invention

The present invention relates to a method and apparatus for coating, and particularly to a method and apparatus for coating food products.

Background and Related Art

The food industry coats food in a variety of different ways of applying coatings, such as batter pastes, to food products. Representative patents showing various ways of applying batter paste to food include US Patent No. 1,870,099 to Croan; US Patent No. 2,287,067 to Schmidt; US Patent No. 3,103,311 to Kempf; US Patent No. 3,288,052. to Hough; US Patent No. 3,459,586 to Kiwiet et al; US Patent No. 3,606,099 to Benson; US Patent No. 3,961,755 to Morine et al .; US Patent No. 4,018,367 to Morine et al .; US Patent No. 4,043,294 to Morine et al .; US Patent No. 4,058,083 to Miller; US Patent No. 4,407,217 to Jackson; US Patent No. 5,328,509 to Essex; US Patent No. 5,463,938 to Sarukawa et al .; US Patent No. 5,478,583 to Jarrett et al .; US Patent No. 5,575,848 to Chedville; and US Patent No. 5,865,890 to Makujina.

US-A-2,876,736 discloses a centrifugal spray apparatus including the properties of the preamble of claims 1 and 3.

One method of applying a coating to food includes dipping the pieces of food in a batter paste. Dipping methods are advantageous in that they provide a coating on the entirety of a piece of food. However, the dipping product is gradually contaminated by the food product residue transferred from the food to the batter as successive pieces of food are spread. Eventually, the batter must be discarded, resulting in a relatively large amount of unused batter being lost.

Another method of coating the food includes spraying a batter paste through a nozzle directed towards the food, which is conveyed on a conveyor belt below the nozzles. Nozzle methods typically provide a coating on only one side of the food product. On the other hand, the nozzles are frequently clogged with batter, especially if the batter includes a particulate product. Thus, the viscosity of the batter paste that can be applied using the nozzle method should be minimized in order to alleviate nozzle clogging. Furthermore, the size of any particulate product contained in the batter should also be minimized to prevent clogging of the nozzles.

Yet another method of applying the coating to food includes the application of rotary sprayers, or rotating discs. Coating a food using a rotary atomizer typically includes spraying the batter through a nozzle onto the surface of a rotating disk, from which the batter is sprayed onto the food product. Typically, the food product is conveyed on the conveyor belt, as in the nozzle method.

What is needed in the art is a device and apparatus for uniformly encapsulating or coating all surfaces of a food product with a relatively high viscosity fluid that can include a particulate product, while minimizing residue and pollution.

Summary

Advantages provided by the present system and device include a method of encapsulating or providing a substantially uniform coating on all sides of the food product. The device and method provide a substantially uniform coating of elements regardless of their position on a conveyor belt. The method also provides minimal contamination of the batter, thus allowing recycling and reuse of the batter previously distributed from the sprinkling process. The devices and methods of the present disclosure also allow fluids with a wide range of viscosities to be applied to food products. Furthermore, the design of the present rotary atomization devices allows a wide range of particle sizes to be added to the fluid and distributed from the device without clogging the fluid distribution nozzles.

The invention is defined in independent claims 1 and 3. Other features of the invention are described in the dependent claims.

In one embodiment, the present disclosure is directed to a rotary atomization device that includes two spaced opposed discs, each having a perimeter and an interior surface. A central cube is arranged in the middle of them and connects each disk. A bore extends coaxially with the first disc, the central hub, and the second disc. A rim extends substantially perpendicularly from the inner surface of each disc along the perimeter of each disc.

ES 2 302 734 T3

In another embodiment, the present disclosure is directed to a rotary atomization device that includes a disk having a perimeter and opposing outer surfaces. A truncated cone extends from each opposing outer surface. Each truncated cone has an external surface and a face parallel to the disk. A hole extends coaxially through the disk. A rim extends substantially perpendicularly from each opposing outer surface of the disc along the perimeter of the disc.

Brief description of the drawings

It should be understood that the drawings are provided for purposes of illustration only and are not intended to define the limits of the invention. The foregoing and other objects and advantages of the embodiments described below will become apparent with reference to the following detailed description when considered in connection with the accompanying illustrative drawings, in which:

Fig. 1 is an isometric view of an embodiment of a rotary atomization device according to the present disclosure;

Fig. 2 is a sectional view of the device of Fig. 1;

Fig. 3 is a sectional view of the device of Fig. 1 showing the engagement with a bushing and a drive shaft;

Fig. 4 is a side view of the central hub of the device of Fig. 1;

Fig. 5 is a top view of the device of Fig. 1;

Fig. 6 is an isometric view of another embodiment of a rotary atomization device according to the present disclosure;

Fig. 7 is an isometric view of a disk of the device of Fig. 6;

Fig. 8 is a sectional view of the device of Fig. 7;

Fig. 9 is an isometric view of an encapsulating disc of the device of Fig. 6;

Fig. 10 is a sectional view of the potting disk of Fig. 9;

Fig. 11 is an isometric view of one embodiment of an apparatus for applying fluid to a surface, with the lid in a closed position;

Fig. 12 is an isometric view of the apparatus of Fig. 11 with the lid in an open position;

Fig. 13 is a sectional view of the apparatus of Fig. 11;

Fig. 14 is an isometric view of the drawer of the apparatus of Fig. 11;

Fig. 15 is a side view of the device of Fig. 1 showing relative engagement with a fluid distribution tube;

Fig. 16 is a front view of another embodiment of apparatus for applying fluid to a surface;

Fig. 17 is a rear view of the apparatus of Fig. 16;

Fig. 18 is an isometric view of the lid portion of the apparatus of Fig. 16;

Fig. 19 is a top isometric view of the lid portion of the apparatus of Fig. 16;

Fig. 20 is an isometric view of an accessory for use with the rotary atomization devices of the present disclosure;

Fig. 21 is a section of the accessory of Fig. 20;

Fig. 22 shows the accessory of Fig. 20 along line 22-22;

Fig. 23 shows the accessory of Fig. 20 along line 23-23;

Fig. 24 shows a sectional view of the accessory of Fig. 20 in cooperative engagement with an embodiment of a rotary atomizer according to the present disclosure; Y

ES 2 302 734 T3 Fig. 25 shows a sectional view of the accessory of Fig. 20 in cooperative engagement with additional rotary atomizers according to the present description.

Detailed description of the preferred embodiments

The present description is about a system and a method for applying a fluid product to an element using a fluid dispenser or a rotary atomization device, and an apparatus including the device, and a method of using the device and the apparatus. The rotary atomization device allows fluids of varying viscosities to be applied to a surface. Regardless of the viscosity of the fluid, the rotary atomizer is also useful for applying fluids that can include relatively large amounts of particulate product. The device has particular utility for applying food batter, especially relatively viscous batter, to at least a solids content of about 50 percent.

In a preferred embodiment, the device and method can be used to distribute a batter onto food products to coat the food products. The device and method allow an unexpectedly wide range of batter viscosities to be applied to food products, as well as batter pastes that include relatively large particles, without clogging the apparatus and minimizing contamination of the batter.

With reference to figs. 1-5 an embodiment of a rotary atomization device 10 according to the present disclosure is illustrated. Fig. 1 illustrates device 10 in perspective view including two opposing discs 12a, b spaced apart. As shown in Figs. 2 and 3, the opposed disks 12a, b spaced apart from one another are substantially symmetrical about a plane "Pi" and each includes an inner surface 14a, b, an outer surface 16a, b, and a perimeter 18a, b. In the present embodiment, the spacing S₁ between the discs 12a, b is preferably about 5 cm (about 2 inches), and each disc 12a, b preferably has a diameter D1 of about 17.5 cm (about 7 inches).

A centrally arranged hub 20 having an outer surface 22 connects the inner surfaces 14a, b of the discs 12a, b. An axial bore 24 extends through hub 20 in coaxial alignment with axis "a", which is substantially perpendicular to plane P₁. Preferably, bore 24 includes stages 24a and 24b, for engagement with bushing 26 and drive shaft 30, as shown in Fig. 3, the purpose of which will be explained in more detail below. Bushing 26 is preferably a quick-set keyless bushing or torque transmission bushing. A plurality of openings 32 may preferably be disposed radially over bore 24 of central hub 20 to allow engagement of central hub 20 with each disc 12a, b by fasteners 34, illustrated herein as screws.

As shown in Figs. 2-4 taken together, the outer surface 22 of the central hub 20 includes two surfaces 22a, b that intersect in the plane P₁. The external surfaces 22a, b are substantially symmetrical with respect to the plane P₁, and extend from the plane P₁ towards the perimeter 18a, b, respectively, to define an angle θ₁, which is preferably less than about 90 degrees, more preferably about 30 degrees to about 60 degrees. Thus, the outer surfaces 22a, b provide the central hub 22 with a substantially vee-shaped, or hourglass-shaped, outer surface 22. The angle θ₁, of the outer surface 22 with the hub 20 may be important to maximize the amount of fluid that can be dispensed from the device 10, as will be explained in more detail below. As shown in Fig. 5, in the present embodiment, the central hub 22 preferably has a diameter D₂ about 6.5 cm (about 2.5 inches).

Referring again to Figs. 2 and 3, the ridges 36a, b extend substantially perpendicularly from each inner surface 14a, b along the perimeter 18a, b. The flanges 36a, b may have a width W₁ ranging from about 0.6 cm to about 5 cm (about 1/4 inch to about 2 inches), preferably from about 1.2 cm to about 3.8 cm (about 1/2 inch to about 1½ inches). In the present embodiment, the width W1 is about 1.2 cm (about 1½ inches). For ease of machining, the intersection of the inner surface of each disc 12a, b with the ridges 36a, b preferably has a radius of about 0.6 cm (about ¼ inch). The radius is thought to enhance fluid movement toward the end of the rim, where it is atomized. However, a perpendicular intersection of the inner surface of each disc 12a, b with the ridges 36a, b is also possible.

In some embodiments, the inner surface 14a, b of each disc 12a, b may include a groove 38a, b into which a shoulder 39a, b of the central hub 20 may be received. Preferably, the recess 38a, b may have a diameter sufficient to allow friction fit of the central hub 20 therein.

Disks 12a, b, and central hub 22 may be unitary or in one piece, depending on the material of construction and the method of constructing the disks. Preferably, when used in the food industry, the device 10 is machined or molded from a food grade material including plastics such as Delrin.^®or ultra-high molecular weight polyethylene (UMHW-PE) and metals such as grade 304/316 stainless steel. Those skilled in the art will recognize that the dimensions of the device 10 may vary as necessary depending on the particular application in which it is used. All surfaces of device 10, in the present embodiment, are substantially smooth and flat. Those skilled in the art also recognize that it is possible

ES 2 302 734 T3 that any or all of the surfaces of the device 10 include patterns or grooves machined therein, as is known in the rotary atomization art, if this improves the performance of the devices.

Next, another embodiment of a rotary atomization device 100 according to the present description will be presented with reference to Figs. 6-10. Device 100 includes a plurality of sequentially arranged discs 102. In the preferred embodiment, encapsulating discs 104 can be positioned at opposite ends of the sequence of discs 102. The structure of the discs 102 allows them to be coupled together in a sequential arrangement, which increases the amount of fluid that can be applied to one surface or allows the application of fluid to a larger surface than is possible with the device 10.

A single disk 102 will now be described with reference to Figs. 7-8. As shown, disk 102 is substantially symmetrical in construction with respect to plane "P2". Each disc 102 includes opposing side surfaces 106a, b having a perimeter 108. A centrally disposed truncated cone 108a, b, can be positioned on each side surface 106a, b. The cone trunks 108a, b each have a top surface 110a, b, and an outer surface 112a, b. An axial bore 114 extends through cone trunks 108a, b in coaxial alignment with the axis; "to₂", Which is substantially perpendicular to the plane P₂. The ridges 116a, b extend substantially perpendicularly from each side surface 106a, b along the perimeter 108. Preferably, a plurality of openings 118 are formed in the upper surfaces 110a, b of each frusto cone 108a, b to receive pins 120, as explained in greater detail below.

A single potting disk 104 will now be illustrated with reference to Figs. 9-10. As shown, disk 104 includes a perimeter 108 and two opposite sides 120a, b. Side 120a is substantially similar in construction to side surface 106a of disk 102, while side 120b is substantially flat. Thus, side 120a includes a centrally disposed truncated cone 108a having a top surface 110a and an outer surface 112a. An axial bore 114 extends through stem 108a in coaxial alignment with axis "a₃"Which is substantially perpendicular to the plane P₃. The bore 114 includes a step 122 for receiving a torque transmission bushing. Preferably a plurality of openings 118 are formed in upper surface 110a of frusto cone 108a to receive pins 120.

As in the previous embodiment, the dimensions of the disks 102 and potting disks 104 may vary depending on the particular application in which they are used. In the present embodiment, each disc 102 and 104 has an outer diameter Di of approximately 17.5 cm (approximately 7 inches). Diameter D₂ of the central hub is preferably about 6.5 cm (about 2.5 inches), and the spacing S₁ between each sequential disk 102 and between disk 102 and potting disk 04 is preferably about 5 cm (about 2 inches).

As in the previous embodiment, the discs 102 and 104 may have a unitary or a one-piece construction, depending on the material of construction and the method of constructing the discs. Preferably, when used in the food industry, device 100 is machined or molded from a food grade material that includes plastics such as Delrin.^® or ultra-high molecular weight polyethylene (UMHW-PE) and metals such as 304/316 grade stainless steels. Those skilled in the art will recognize that the dimensions of device 100 may vary as needed depending on the particular application in which they are used.

All surfaces of device 100, in the present embodiment, are substantially smooth and flat. Those skilled in the art will also recognize that any or all of the surfaces of the device 10 may include patterns or grooves machined therein, as is known in the rotary atomization art, if this improves the performance of the devices.

Figures 11-14 illustrate another aspect of the present disclosure, which corresponds to an apparatus 150 for coating items with a flowable material, preferably for coating food items with a batter paste. An exemplary apparatus 150 is shown in perspective view in Figs. 11 and 12. As shown, apparatus 150 includes a frame 152 that supports a compartment 154 having an inlet end 156 and an outlet end 158. Compartment 154 includes a base 160 connected to a lid 162. Base 160 preferably has downward sloping sides 160a, b that intersect at the lower end 162 of base 160 above a fluid reservoir 64. Cap 162 can be hinged to base 160 in preferred embodiments. A control panel 166 may be conveniently provided on the lid 162 to allow an operator to operate various controls. Apparatus 150 may be supplied with power by any suitable means.

A plurality of the previously described rotary atomization devices are disposed within the cap 162 and base 160. Although illustrated here with various rotary atomization devices, those skilled in the art will recognize that only one may be necessary, depending on the particular application. Similarly, any number of devices 10 can be included in an apparatus, if needed or desired. As best shown in Fig. 13, two devices 10a, b are arranged in the lid 162. Each device 10a, b is supported by drive shafts 168a, b which extend through cover 162 to connect motor 170a, b with drive shafts 168a, b.

Base 160 includes a support member 172 to support several of the foregoing rotary atomization devices. As best shown in Figs. 13 and 14 when taken together, member 172

ES 2 302 734 T3 of the support has a drawer-shaped construction which allows it to be removably removed from base 160 using, for example, a handle 174. Two devices 10a and two devices 10b are arranged on opposite sides of the drawer 172. Each of the four devices 10a, b rest on the drive shafts 176a, b extending along the wall of the drawer 172 to connect to the motors 178a, b, which rotatably drive the shafts 176a, b. A fluid distribution tube 180 (not shown in each drawing) may be provided within each device 10a, b proximate the outer surface of the central hub. Distribution tube 180 may have a diameter ranging from about 0.3 cm to about 2.5 cm (about 1/8 inch to about 1 inch), preferably about 0.6 cm to about 1.9 cm. (approximately * 4 inches to approximately% inches). In the present embodiment, the diameter of distribution tube 180 is approximately 1.2 cm (approximately * / 2 inch). An exemplary arrangement of a fluid distribution tube 180 between the discs 12a, b is illustrated in FIG. 15.

Fluid distribution tube 180 can dispense fluid drawn from fluid reservoir 164 containing a source of fluid to be dispensed through a variety of suitably connected fluid distribution lines. As illustrated in Figs. 11-13, two motor-driven pumps 182, 184 rest on frame 152. Pump 182 draws fluid from reservoir 164 through line 186 and distributes fluid through lines 188 extending across the face of drawer 172 to fluidly connect devices 10a, b, as best shown. in Fig. 14. Similarly, pump 184 draws fluid from reservoir 164 through line 190 (see Fig. 13) and distributes fluid through lines 192a, b which are fluidly connected to the devices 10a, b inside cover 162. The foregoing distribution lines may have a diameter ranging from about 1.2 cm to about 5 cm (about * / 2 inch to about 2 inches), more preferably from about 1.9 cm to about 3.8 cm (about% inch to about 1½ inches). In the present embodiment, the diameter of the distribution lines is about 1.2 cm (about 1½ inches).

A conveyor assembly indicated generally by 194 includes a motor 196 for rotationally driving a plurality of rollers 198 disposed at various locations within base 160 and upon which is positioned a conveyor member 199, which is illustrated herein as a belt. Band 199 is operatively arranged for transverse movement within base 160 from inlet end 156 to outlet end 158. Such transport assemblies are well known in the art and will not be described in detail here. Preferably, rollers 198 are arranged such that conveyor member 199 substantially conforms to sides 160a, b of base 160.

Preferably, when used in the food industry, the components of the appliances 150 with which the food comes into contact can be constructed of a food grade product including plastics such as Delrin® or ultra-high molecular weight polyethylene (UMHW- PE) and metals such as 304/316 grade stainless steels. Those skilled in the art will recognize that the dimensions of the apparatuses 150 can vary as needed depending on the particular application in which they are used.

In operation, power is supplied to the system, and items to be coated, preferably food items, are placed on the conveyor belt. The rotary atomizing devices 10a, b can be set to rotate at a speed of from about 1500 RPM to about 2000 RPM, with about 1723 RPM being optimal. Generally, at slower speeds of rotation, large droplets rather than a fine mist of batter paste are distributed from the discs. On the other hand, the direction in which the batter is distributed is narrower, resulting in a denser, more uneven coating build-up on the food product. Also generally, at high rotational speeds, the residence time of the batter in the device is short to allow it to acquire sufficient momentum to be atomized and thus distributed as a fine mist.

The batter paste can then be removed from the reservoir and distributed to each rotating atomizer device that is rotating on both the lid and the base, while the conveyor belt begins to move. Typical line speeds in the food industry range from about 50 RPM to about 100 RPM. The present methods provide extended lines with speed capabilities ranging from about 5 RPM to about 200 RPM or more, in some cases. The increasing line speeds that are possible with the present method are due in part to the increased capacity of the present rotary spray devices and systems, as well as the increasing residence time of the batter in the rotary spray devices. Those skilled in the art will recognize that modifications may be necessary to operate at such a line speed. For example, it may be necessary to use various conveyor belts, or change the rotation speed of the atomizers, change the number and position of the rotating atomizers, change the spacing between the rotating atomizers and the conveyor belt. Such modifications will be apparent to those of ordinary skill in the art and can be accomplished using routine experimentation.

The batter from both the top and bottom food delivery tubes is sprayed onto the center hub of each rotary atomizer. When the batter is brought into contact with the outer surface of the central hub, the batter is deflected in such a way as to affect the edges of the discs. The ridges increase the residence time of the batter on the disc, allowing the batter to gain the necessary momentum to be atomized when the batter is to be battered

ES 2 302 734 T3 leaves the disk. Thus, the inclusion of the flange in the disk design allows a more viscous batter to be dispensed. The increasing momentum provides the energy necessary for the batter to atomize into a fine mist, resulting in a uniform coating on the articles to be coated. The ridges prevent batter from being distributed too rapidly from the disk which would result in, for example, large batter droplets, batter drips, and generally a non-uniform coating. Typically, fluids that have a viscosity of up to approximately 12-14 seconds within a Stein # 3 cup (available from Stein / DSI, which is a subsidiary of FMC Food TECH, located in Sandusky Ohio), and / or a content of Solids of about 50 percent can be distributed using the present devices and methods.

Thus, using the present method, food items can be coated substantially evenly on all sides with a relatively viscous fluid or batter at a relatively high rate that is compatible with most food production lines. food. The rotary atomization device design allows relatively viscous fluids, or batter pastes, to be atomized. The rotary atomization device design also allows relatively large amounts of fluid or batter to be coated without dripping onto the food.

Figs. 16-19 illustrate another exemplary embodiment of a coating apparatus. As seen in the figures, apparatus 250 differs from apparatus 150 in size and shape, but otherwise includes substantially the same components, except for the inclusion of rotary atomization devices 100 instead of devices 10. As far as possible, reference numbers indicating the same or similar components as in the previous embodiment have been changed by substituting the number "1" for the number "2". So 152 becomes 252, and so on.

The use of rotary atomization devices 100 in apparatus 250 provides increased fluid distribution capacity, allowing relatively large quantities of articles to be coated or alternatively, coating at a higher rate. As shown in Figs. 16 -20 when taken together, lid 262 of apparatus 250 includes a plurality of devices 100 mounted for rotation on drive shafts 268 that are rotatably driven by motor 270. Devices 100 can be spaced apart from each other inside cap 262 (best seen in Fig. 18), and staggering with respect to each other within cap 262 so as not to interfere with fluid distribution by adjacent devices 100 (best seen in Fig. 19). Similarly, base 260 of apparatus 250 also includes a plurality of sequentially arranged rotary atomizing devices 100 which are mounted for rotation about drive shaft 276 driven by motor 278.

As in the previous apparatus, the components of the apparatus 250 that come into contact with food can be constructed of a food grade material that includes plastics such as Delrin.^® or ultra-high molecular weight polyethylene (UMHW-PE), and metals such as grade 304/316 stainless steels. Those skilled in the art will recognize that the dimensions of apparatus 250 may vary as necessary depending on the particular application in which it is used.

Figs. 20-25 illustrate another aspect of the present disclosure that focuses on an accessory 300 for use in cooperation with any of the devices 10,100 and as well as with the devices 150, 250. As shown in Fig. 20, the accessory 300 it may include a substantially annular portion 302. As shown in the isometric view of Fig. 21, the ring-shaped portion 302 includes two sections 306, 308 connected by the fasteners 310 that are inserted into the openings 308. The section 308 includes an opening 312 in which the fluid distribution tube 180 can be attached. As shown in Figs. 22-23, each of the sections 306, 308 has a substantially flat internal surface 314a, from which inclined surfaces 316a, b and 318a, b extend outwardly. Section 306 preferably has a substantially curved outer surface 320, while section 308 has a substantially flat outer surface 322.

Figs. 24-25 illustrate an exemplary arrangement using an annular portion 302 in cooperation with disk 102 and potting disk 104. As shown, disks 102, 104 can be mounted on a rotary hollow drive shaft 324, which can be coupled, for example, to a fluid dispenser to receive the fluid or batter paste on the hollow drive shaft 324. The disks 102, 104 are connected by pins inserted into the openings on each opposite side of the disks 102, 104. Before the pins are inserted, the annular portion 302 must be mounted on the frusto-conical portion. Of course, although not illustrated here, the accessory 300 can also be arranged between the disks 12a, b of the device 10.

During operation of an apparatus, fluid is distributed directly from the hollow drive shaft 324 to the annular portion 302, which acts as a channel to collect and distribute the fluid to the inner surfaces of the rotating discs of the devices 10, 100. Thus, any fluid that is dispensed from the hollow drive shaft 324 and that is not immediately thrown onto the cone or internal surfaces of the discs is collected. This prevents fluid that does not yet have the required momentum from being atomized from dripping onto the articles to be coated. Thus, the fitting 302 effectively increases the residence time within the devices 10, 100 of the fluid dispensed from the fluid distribution tubes 180.

Although certain specific structure embodying the invention is shown and described herein, it will be apparent to those skilled in the art that various modifications and changes can be made to the parts without departing from the scope of the appended claims.