Patent Description:
The Model M6™ dicer is a versatile size-reduction machine manufactured by Urschel Laboratories, Inc. , and is particularly well suited for producing size- reduced products by dicing, strip cutting, or shredding a variety of food products, notable but nonlimiting examples of which include leafy vegetables and frozen-tempered, freshchilled, or hot cooked beef, pork, or poultry. The Model M6™ is well known as capable of high capacity output and precision cuts. In addition, the Model M6™ has a sanitary design to deter bacterial growth.

Commercial embodiments of the Model M6™ dicer comprise a size- reduction unit, for example, a size-reduction unit <NUM> schematically represented in <FIG>, <FIG>, and <FIG>. Product <NUM> is delivered to the size-reduction unit <NUM> with a conveyor unit comprising a feed belt <NUM> driven by a drive roll <NUM>, and undergoes size reduction in the size-reduction unit <NUM> before exiting the dicer as a size- reduced product through an outlet or discharge chute <NUM>. The size-reduction unit <NUM> represented in <FIG>, <FIG>, and <FIG> as comprising a feed roll <NUM>, a circular cutter <NUM><NUM> comprising a row of circular knives <NUM>, a feed drum <NUM>, a stripper plate <NUM>, and a cross-cutter <NUM> comprising multiple crosscut knives <NUM>. Each of the feed roll <NUM>, drive roll <NUM>, circular cutter <NUM>, feed drum <NUM>, and cross-cutter <NUM> individually rotates about its respective axis of rotation, which are generally parallel to each other. In operation, products <NUM> (<FIG>) of a predetermined thickness range are delivered to the size-reduction unit <NUM> on the feed belt <NUM>. Each product <NUM> is pinched between the feed roll <NUM> and the drive roll <NUM> at the end of the feed belt <NUM>. The feed roll <NUM> is preferably spring loaded and adjustable to allow products <NUM> of varying thicknesses to move through the unit <NUM> without being crushed. The feed belt <NUM> forces the product <NUM> into the circular cutter <NUM>, whose circular (disk-shaped) knives rotate through complementary grooves formed in the feed drum <NUM>. The circular knives <NUM> of the circular cutter <NUM> are oriented perpendicular to the rotational axis of the circular cutter <NUM>, such that the circular cutter <NUM> cuts the product <NUM> into multiple parallel strips that are then removed from its circular knives <NUM> by the stripper plate <NUM> before being delivered to the cross-cutter <NUM>. The stripper plate <NUM> has a shear edge <NUM> at which cross-cuts made by the knives <NUM> of the cross-cutter <NUM> occur to reduce the strips to produce, for example, cubes, or rectangular-shaped size-reduced "diced" product <NUM>.

As shown in <FIG>, the shear edge <NUM> of the stripper plate <NUM> provides the location at which cross-cuts are made by the knives <NUM> of the cross-cutter <NUM><NUM>, and a second shear edge <NUM> defined by the stripper plate <NUM> serves to extract the strips from the circular cutter <NUM> prior to being diced with the cross-cutter <NUM>. Slots <NUM> are defined in the stripper plate <NUM> facing the circular cutter <NUM> and partially receive the knives <NUM> of the circular cutter <NUM>. The slots <NUM> extend to the shear edge <NUM>, such that individual edges of the shear edge <NUM> between adjacent slots <NUM> protrude between adjacent knives <NUM> of the circular cutter <NUM><NUM> to remove strips from therebetween. The width of each slot <NUM> of the stripper plate <NUM> is sufficient to accommodate the axial thickness of one knife <NUM> of the circular cutter <NUM> received therein and provide a clearance therebetween. The slots <NUM> also define parallel walls that separate adjacent knives <NUM> of the circular cutter <NUM> from each other.

The shear edge <NUM> of the stripper plate <NUM> is in close proximity to the knives <NUM> of the cross-cutter <NUM> to ensure complete dicing of the strips delivered from the circular cutter <NUM> to the cross-cutter <NUM>, producing the final cross-cuts that yield the diced product <NUM>. The knives <NUM> are generally rectilinear in shape and oriented approximately parallel to the rotational axis of the cross-cutter <NUM>, and therefore parallel to the shear edge <NUM> of the stripper plate <NUM><NUM> and transverse and perpendicular to the circular knives <NUM> of the circular cutter <NUM>. The parallel relationship of the cutting edges of the knives <NUM> and the shear edge <NUM> define what is referred to herein as a zero shear angle. The knives <NUM> are separate components attached to a rotor <NUM> of the cross-cutter <NUM>, and between adjacent knives <NUM> the rotor <NUM> defines a channel <NUM> that is parallel to the rotational axis of the cross-cutter <NUM>. The rotational speed of the cross-cutter <NUM> is preferably independently controllable relative to the circular cutter <NUM> and feed drum <NUM> so that the size of the diced product <NUM> can be selected and controlled.

<FIG> schematically represents the trajectory of a diced product <NUM> as it exits the size-reduction unit <NUM> and subsequently falls downward through the discharge chute <NUM> of the machine. As evident from <FIG>, as a knife <NUM> of the cross-cutter <NUM> engages a product <NUM>, the product <NUM> is impacted by the knife <NUM> as the entire cutting edge of the knife <NUM> simultaneously engages the product <NUM>, referred to herein as a chopping cut. Thereafter, as the cross-cutter <NUM> continues to rotate, the resulting diced product <NUM> is impacted by the channel <NUM> preceding the knife <NUM> that produced the diced product <NUM>. The channel <NUM> accelerates the product <NUM> to the velocity at the radial location on the rotor <NUM> that impacts the product <NUM>, and thereafter the cross-cutter <NUM> propels the product <NUM> along the trajectory depicted in <FIG>.

In addition to the size-reduction unit <NUM> depicted in <FIG>, commercial embodiments of the Model M6™ dicer can be equipped with size-reduction units that differ in their components and the size-reduced products they produce. For example, the feed roll <NUM> of <FIG> may be replaced with a top belt assembly that comprises a feed belt driven by a drive roll, or the unit may be configured for shredding by replacing the circular cutter <NUM> with a feed spindle and replacing the cross-cutter <NUM> with a shredder to produce shredded product. As such, the term "dicer" is not limited to machines with the size-reduction unit <NUM> of <FIG>.

While the Model M6™ is widely used and well suited for many food processing applications, there is an ongoing desire for greater productivity in machines of this type.

<CIT> discloses a rotary cutting apparatus in which the cutting of thin material is possible without the use of a curved blade. The fly and bed knives are positioned according to the formula <MAT> where C is bed knife camber, R is cutting radius, S is shear angle and L is rotor length. As a result of this geometry, uniform fly knife to bed knife clearance is maintained across the face of the rotor. <CIT> discloses a machine for cutting slabs of fresh or frozen tempered meat into diced sections and defined by a conveyor assembly comprised of a feed belt and an associated spring-biased feed roll, a strip cutting assembly comprised of a first knife roll of circular knives and an associated drum, and a crosscut assembly comprised of a second knife roll of elongate knives and an associated stripper plate provided with a corresponding shear edge, with edge portions of the circular knives being intermeshed within slots formed in the stripper plate and peripheral grooves formed in both the feed roll and feed drum. The feed drum is configured to retard the movement of fresh meat slabs being conveyed through the strip cutting assembly during which the circular knives are rotated at a peripheral speed that is at least twice the peripheral speed of the feed drum. <CIT> discloses zero-clearance cutting via a cutting area including a sacrifice material that is relatively softer than the cutter. One example is a cutting system which is capable of cutting a material such as, for example, tape or paper, into a fiber or powder. The cutting system includes a cutting blade, typically a rotary cutter, and a sacrificial plate or round bar contacting the cutting blade. The contacting portion has a zero clearance during the cutting operation. A metering mechanism is also provided which is capable of metering the material at a predetermined rate to the cutting blade. A mechanism is also provided for incrementally moving the sacrificial blade towards the cutting blade to ensure that the zero clearance is maintained between the cutting blade and the sacrificial plate, even when the sacrificial plate begins to wear down due to usage. Also, destruction of the material is further enhanced by advantageous strategic patterning of cutting edges on a rotary cutter, and further by secondary shredding features. Systems are provided for reducing to-be-destroyed paper and other relatively-thin planar materials to a dust or powder-size.

The present invention provides size-reduction units, size-reduction machines, and methods capable of producing size-reduced products from a variety of solid and semisolid materials. The invention is defined by the independent claims and optional features are defined by the dependent claims.

According to the invention a size-reduction unit includes a circular cutter adapted and arranged to cut a product into strips, a rotating cross- cutter adapted and arranged to receive the strips from the circular cutter, and a stripper plate. The cross-cutter comprises knives each having an arcuate surface that terminates at an adjoining cutting edge, the cutting edges being adapted and arranged to cut the strips into a size-reduced product, each of the cutting edges being at a constant radius from an axis of rotation of the cross-cutter and having a helical geometric shape, the arcuate surface of each of the knives defining an arcuate transition to a radial location of the arcuate surface at which the size-reduced product is stabilized and cradled when the cross-cutter is rotating, and the stripper plate defining a shear edge in proximity to the cutting edge of each knife of the cross-cutter as its cutting edge encounter the shear edge during rotation of the cross-cutter. The cross-cutter has a helical fluted shape comprising flutes between adjacent pairs of the knives, each of the arcuate surfaces defines a flute angle (θ) of greater than <NUM> degrees to less than <NUM> degrees at the cutting edge thereof, and each of the flutes has a radial depth that is at least <NUM>% of the constant radius of the cutting edges. The flutes have helical shapes and are not parallel to an axis of rotation of the cross-cutter, and each of the cutting edges has a nonparallel relationship with the shear edge of the stripper plate to define a non-zero shear angle (φ).

According to another aspect, a dicing machine is provided that includes a size-reduction unit of the type described above.

Other aspects include methods of using size-reduction units and size-reduction machines of the types described above. Such methods include feeding product to the circular cutter to produce the strips and then dicing the strips with the cross-cutter to produce size-reduced product.

A technical effect of the invention is the ability of the cross-cutter to more gradually accelerate size-reduced product over a relatively long period of time, resulting in much lower impact forces and less damage to the size-reduced product.

Other aspects and advantages of this invention will be better appreciated from the following detailed description.

<FIG> represent isolated views of a size-reduction unit <NUM> configured to be installed on a size-reduction machine, as a nonlimiting example, the Model M6™ represented in <FIG>, and <FIG> through <FIG> and <FIG> through <FIG> represent alternative configurations of components that can be utilized in the size-reduction unit <NUM>. The unit <NUM> is particularly adapted to slice a product and then cut the resulting sliced product (strips) in a direction transverse to the cut that produced the strips (a "cross-cut") to achieve size reduction and produce a size-reduced product, as a nonlimiting example, dicing to produce a diced product. However, those skilled in the art will appreciate that the size-reduction unit <NUM> and its benefits are not limited to such uses. Furthermore, though the invention will be described hereinafter in reference to a dicer machine of a type shown in <FIG>, it will be appreciated that the teachings of the invention are more generally applicable to other types of size-reduction machines. In view of similarities between the unit <NUM> and its components shown in <FIG> and <FIG> and the size-reduction unit <NUM> and its components shown in <FIG>, the following discussion will focus primarily on certain aspects of the unit <NUM> and its components, whereas other aspects not discussed in any detail may be, in terms of structure, function, materials, etc., essentially as was described for the size-reduction unit <NUM> and its components of <FIG>.

Similar to the size-reduction unit <NUM> of <FIG>, the size-reduction unit <NUM> represented in <FIG> is schematically represented as comprising a feed roll <NUM> (<FIG>), a circular cutter <NUM> comprising a row of circular knives <NUM>, a feed drum <NUM>, a stripper plate <NUM>, and a cross-cutter <NUM> comprising multiple crosscut knives <NUM>. Product <NUM> (<FIG>) is delivered to the unit <NUM> via a feed belt <NUM> driven by a drive roll <NUM>, both of which are components of a conveyor unit <NUM>. The feed roll <NUM>, circular cutter <NUM>, feed drum <NUM>, cross-cutter <NUM>, and drive roll <NUM> are individually mounted on spindles 52a-e and rotate about respective axes of rotation that are parallel to each other. The stripper plate <NUM> is mounted to a support bar <NUM> to maintain its orientation with the knives <NUM> of the circular cutter <NUM>.

In operation (<FIG>), the product <NUM> is delivered to the size-reduction unit <NUM> on the feed belt <NUM>. The feed roll <NUM> is preferably spring-loaded and/or adjustable to enable products <NUM> of varying thicknesses to move through the unit <NUM> such that each product <NUM> is pinched between the feed roll <NUM> and drive roll <NUM> at the end of the feed belt <NUM> without being crushed. Each product <NUM> is forced into the circular cutter <NUM>, whose circular (disk-shaped) knives <NUM> rotate through complementary grooves formed in the feed drum <NUM>. The circular knives <NUM> are oriented approximately perpendicular to the rotational axis of the circular cutter <NUM>, such that the circular cutter <NUM> cuts the product <NUM> into multiple parallel strips that are then removed from its circular knives <NUM> by a shear edge <NUM> of the stripper plate <NUM> before being delivered to the cross-cutter <NUM>. The stripper plate <NUM> has a second shear edge <NUM> at which cross-cuts made by the knives <NUM> of the cross-cutter <NUM> occur to reduce the strips to produce, for example, cubes or rectangular-shaped size-reduced "diced" product of predetermined size.

The shear edge <NUM> of the stripper plate <NUM> is in close proximity to the cross-cutter knives <NUM> to ensure complete dicing of strips delivered from the circular cutter <NUM> to the cross-cutter <NUM>. As evident from <FIG>, the knives <NUM> of the cross-cutter <NUM> are not separate components attached to the cross-cutter <NUM>, but instead are integrally formed features of the cross-cutter <NUM>, though such a configuration is not required. Additionally, the knives <NUM> are not rectilinear in shape, nor are they oriented parallel to the rotational axis of the cross-cutter <NUM>, or parallel to the shear edge <NUM>, or perpendicular to the circular knives <NUM> of the circular cutter <NUM>. Instead, the knives <NUM> have an arcuate shape that results in the cross-cutter <NUM> having a shape that will be referred to herein as "helical fluted. " The term "helical" refers to the geometric shape of each cutting edge <NUM> of the knives <NUM>, and the term "fluted" refers to deep flutes <NUM> defined in the cross-cutter <NUM> between adjacent knives <NUM>. The flutes <NUM> are not parallel to the rotational axis of the cross-cutter <NUM>, but instead have helical shapes similar to the cutting edges <NUM> of the knives <NUM>.

Due to the helical shape of the cutting edge <NUM> of each knife <NUM>, the cutting edges <NUM> of the cross-cutter <NUM> have a nonparallel relationship with the shear edge <NUM> of the stripper plate <NUM> to define what is referred to herein as a non-zero shear angle. However, the cutting edge <NUM> is at a constant radius from the axis of rotation of the cross-cutter <NUM>, so that the spacial relationship between the cutting edge <NUM> and the shear edge <NUM> of the stripper plate <NUM> is the same along the entire length of the cutting edge <NUM> as the edge <NUM> progressively interacts with the shear edge <NUM>. As such, the entire cutting edge <NUM> of each knife <NUM> does not simultaneously engage the product <NUM>, but instead the non-zero shear angle results in a shearing or slicing cut as opposed to the chopping cut associated with the cross-cutter <NUM> of <FIG>. As a result, the product <NUM> is sliced progressively across its width rather than all at once, what may be referred to as a scissor action. Progressive slicing requires significantly less force from the crosscutter <NUM> than a chopping cut, imparts less force onto the product <NUM>, and produces a more uniform cut.

After being sliced from the original product <NUM>, a diced product <NUM> (<FIG>) is impacted and captured by the flute <NUM> preceding the knife <NUM> that produced the product <NUM>. The flute <NUM> accelerates the diced product <NUM> to the velocity at the location on the flute <NUM> that captures and cradles the product <NUM>, after which the product <NUM> is propelled from the size-reduction unit <NUM> with centrifugal force as the cross-cutter <NUM> continues to rotate. However, in comparing <FIG>, it can be seen that the depths of the flutes <NUM> are greater than the depths of the channels <NUM> of the cross-cutter <NUM> of <FIG>, depicted as being approximately <NUM>% of the radius of the cross-cutter <NUM>. The depths of the flutes <NUM> are preferably at least half of the radius of the cross-cutter <NUM>, and in the embodiments shown the depths of the flutes <NUM> are approximately <NUM>% of the radius of the cross-cutter <NUM>. The deep fluted design of the cross-cutter <NUM> provides a smooth arcuate transition on each flute <NUM>, which decreases the acceleration to which the diced product <NUM> is subjected after it is impacted and captured by the flute <NUM>. By comparing <FIG>, it can be also seen that the diced product <NUM> is stabilized and cradled in the flute <NUM> at a radial location of the cross-cutter <NUM> that is much closer to the axis of rotation of the cross-cutter <NUM>, at which point the velocity of the product <NUM> is the same as the local velocity of the cross-cutter <NUM>, so that the velocity of the product <NUM> is lower than if it were cradled at a radial location in the flute <NUM> farther from the axis of rotation.

The combined effect of the helical and fluted features of the cross-cutter <NUM> is to reduce the cutting and impact loads on the original and diced products <NUM> and <NUM>, resulting in less product damage as compared to the cross-cutter <NUM> of <FIG> when operating at the same rotational speed. Consequently, the size-reduction unit <NUM> can be operated at higher speeds to increase product throughput, the result of which can be more product processed per hour with the same or less damage to the product. Such benefits are particularly significant when dicing soft or delicate products, as nonlimiting examples, cooked chicken, baked goods such brownies and bread, and granola bars.

During investigations leading to the present invention, it was determined that the flute angle, defined herein as the angle between a radial of the cross-cutter <NUM> and a plane containing the surface of the flute <NUM> adjacent its adjoining cutting edge <NUM>, is pertinent to the operation of the cross-cutter <NUM>. As more readily observed in <FIG>, the cross-cutter <NUM> shown in <FIG> has a flute angle (θ) of about <NUM> degrees. Flute angles significantly greater than <NUM> degrees, for example, about <NUM> degrees or more, have been observed to detain the diced product <NUM> in the flute <NUM> instead of being expelled, such that diced products <NUM> tend to collect in the flutes <NUM>. This observation is believed to be attributable to the frictional force on the surface of the flute <NUM> being larger than the centrifugal force imparted by the rotation of the cross-cutter <NUM>. On the other hand, flute angles significantly less than <NUM> degrees, for example, about <NUM> degrees or less, tend to impart a greater acceleration on the diced product <NUM> during and after being sliced, increasing the risk of damage to the product <NUM>.

With reference to <FIG>, the shear angle (φ) of a cross-cutter knife <NUM> is defined herein as the angle between the cutting edge <NUM> of that knife <NUM> and a line that intersects the edge <NUM> and is parallel to the axis of rotation of the cross-cutter <NUM>. The cross-cutter <NUM> shown in <FIG> has a shear angle of about <NUM> degrees, though any shear angle other than zero degrees has the effect of decreasing cutting load. As previously noted, a clean and uniform cut is promoted by the entire cutting edge <NUM> being at a constant radius from the axis of rotation of the cross-cutter <NUM>, such that a constant shear edge gap exits with the shear edge <NUM> of the stripper plate <NUM>. As a consequence, the shear angle follows a helical curved path. As evident from <FIG>, if the shear angle were to be straight, the resulting cutting edges <NUM>' of the cross-cutter <NUM> would not maintain a constant shear edge gap and would produce a lower quality cut.

<FIG> represent results of dynamic modeling performed to compare the elastic impacts and rigid body dynamics of a cross-cutter of the type represented in <FIG> and a cross-cutter of the type represented in <FIG>. <FIG> indicates that the simulated cross-cutter of <FIG> would impact and accelerate a diced product over a span of about <NUM> milliseconds, corresponding to a very harsh impact and high acceleration. In comparison, <FIG> indicates that the cross-cutter of <FIG> more gradually accelerates a diced product over a much longer span of about <NUM> milliseconds, corresponding to a much lower impact on the product.

During additional investigations leading to the present invention, the performances of experimental cross-cutters within the scope of the present invention were compared with a prior art cross-cutter of the type shown in <FIG>. Cooked chicken breasts were fed into a Model M6™ dicer, which sliced the chicken with a circular cutter (for example, <NUM> in <FIG>, and <NUM> in <FIG> and <FIG>) before undergoing cross-cutting with the installed cross-cutter to produce a diced chicken product. The prior art cross-cutter had a conventional zero shear angle (as defined in reference to <FIG>), whereas an experimental cross-cutter had a helical fluted configuration (as defined above in reference to <FIG>) characterized by a <NUM>-degree (non-zero) shear angle. For comparison, a second experimental cross-cutter was also evaluated that had a fluted configuration (as defined above in reference to <FIG>), but whose cutting edges did not have a helical shape. Consequently, the experimental cross-cutters differed as a result of the experimental helical fluted cross-cutter having a non-zero shear angle resulting from the helical geometric shape of its knife cutting edges, and the experimental fluted cross-cutter having a zero shear angle resulting from its knife cutting edges being parallel to its rotational axis. The diced chicken product was assessed on the basis of the yield of product too large to pass through a <NUM> (<NUM>/<NUM> inch)
screen. When operating with the prior art, experimental helical fluted, and experimental fluted cross-cutters, the Model M6™ dicer produced a yield of, respectively, <NUM>%, <NUM>%, and <NUM>%. The significantly improved yield exhibited by the experimental fluted cross-cutter was attributed to the reduced impact loads resulting from its fluted configuration, and the greater improved yield exhibited by the experimental helical fluted cross-cutter was attributed to the combined effects of reducing cutting loads and impact loads resulting from, respectively, its combined helical and fluted configurations.

<FIG>, <FIG>, and <FIG> are isolated views of alternative embodiments of cross-cutters suitable for use in the size-reduction unit <NUM> of <FIG> and a size-reduction machine of the type represented in <FIG>. <FIG> depicts a herringbone design in which the cutting edge <NUM> of each knife <NUM> of the cross-cutter <NUM> has a segment located in one of two opposite longitudinal halves of the crosscutter <NUM>. The segments of each cutting edge <NUM> has opposite but equal helix angles (and shear angles), with each half of the cutting edge <NUM> retaining the helical and fluted design aspects of the cross-cutter <NUM> of <FIG>. A herringbone cross-cutter <NUM> such as shown in <FIG> causes diced products <NUM> to travel through the flutes <NUM> in opposite axial directions away from an apex <NUM> of each cutting edge <NUM>, which is shown but not required to be located at the longitudinal center of each knife <NUM>. A benefit of this design is that there is no net axial load on bearings supporting the cross-cutter <NUM>.

<FIG> depicts a cross-cutter <NUM> whose knives <NUM> are replaceable, but otherwise retains the helical and fluted design aspects of the cross-cutter <NUM> of <FIG>. The cross-cutter <NUM> of <FIG> comprises a rotor 42a, multiple knives 42b, a knife holder 42c for each knife 42b, and end caps 42d (<FIG>) for retaining the knife holders 42c in slots 42e formed in the rotor 42a. A benefit of the replaceable knives <NUM> is the ability to replace any or all of the knives 42b in the event that they become worn or damaged.

<FIG> depicts a cross-cutter <NUM> that is also equipped with replaceable knives <NUM>, and which is useful for understanding the context of the claimed invention. Though the cross-cutter <NUM> retains the fluted design aspect of the crosscutter <NUM> of <FIG>, it does not retain its helical aspect. Similar to the embodiment of <FIG>, the cross-cutter of <FIG> comprises a rotor 42a, multiple knives 42b secured to the rotor 42a at a knife holder 42c, and end caps 42d (only one of which is shown).

<FIG> are various views of an alternative embodiment of a conveyor unit <NUM> useful for understanding the context of the claimed invention and suitable for use with the size-reduction units of <FIG>, cross-cutters of <FIG> and <FIG> through <FIG>, and a size-reduction machine of the type represented in <FIG>. In the embodiment shown, the belt <NUM> upstream of the entrance to the size-reduction unit <NUM> defines an infeed belt section 46a, and the belt <NUM> extends into the discharge chute <NUM> to further provide an outfeed belt section 46b at the outlet of the size-reduction unit <NUM>. The entire belt <NUM> may be driven by a single drive roller <NUM>, instead of two separate drive rollers that would be required to operate separate infeed and discharge conveyors. The conveyor unit <NUM> includes a reversing roll <NUM> so that the infeed and outfeed belt sections 46a and 46b of the belt <NUM> are staggered at different heights. A benefit of this design is that diced product <NUM> thrown from the cross-cutter <NUM> travels in the same direction as the direction of travel of the outfeed belt section 46a. The result is a lower velocity differential between the product <NUM> and the surface (belt section 46b) first encountered by the product <NUM> after leaving the size-reduction unit <NUM>, thus minimizing impact forces as compared to landing against the static discharge chute <NUM>. Another benefit is that small fines resulting from the dicing process cannot fall between the entrance and outlet of the size-reduction unit <NUM> because there is no gap between the infeed and outfeed sections 46a and 46b. Yet another benefit is that sticky diced product <NUM> is less likely to stick to the belt <NUM> as compared to being thrown against the static discharge chute <NUM>.

Claim 1:
A size-reduction unit (<NUM>) comprising:
a circular cutter (<NUM>) adapted and arranged to cut a product (<NUM>) into strips;
a rotating cross-cutter (<NUM>) adapted and arranged to receive the strips from the circular cutter (<NUM>), the cross-cutter (<NUM>) comprising knives (<NUM>) each having an arcuate surface that terminates at an adjoining cutting edge (<NUM>), the cutting edges (<NUM>) being adapted and arranged to cut the strips into a size-reduced product (<NUM>), each of the cutting edges (<NUM>) being at a constant radius from an axis of rotation of the cross-cutter (<NUM>) and having a helical geometric shape, the arcuate surface of each of the knives (<NUM>) defining an arcuate transition to a radial location of the arcuate surface at which the size-reduced product (<NUM>) is stabilized and cradled when the cross-cutter (<NUM>) is rotating;
a stripper plate (<NUM>) defining a shear edge (<NUM>) in proximity to the cutting edge (<NUM>) of each of the knives (<NUM>) of the cross-cutter (<NUM>) as the cutting edges (<NUM>) encounter the shear edge (<NUM>) during rotation of the cross-cutter (<NUM>);
wherein the cross-cutter (<NUM>) has a helical fluted shape comprising flutes (<NUM>) between adjacent pairs of the knives (<NUM>), each of the arcuate surfaces defines a flute angle (θ) of greater than <NUM> degrees to less than <NUM> degrees at the cutting edge (<NUM>) thereof, and each of the flutes (<NUM>) has a radial depth that is at least <NUM>% of the constant radius of the cutting edges (<NUM>);
wherein the flutes (<NUM>) have helical shapes and are not parallel to an axis of rotation of the cross-cutter (<NUM>); and
wherein each of the cutting edges (<NUM>) has a nonparallel relationship with the shear edge (<NUM>) of the stripper plate (<NUM>) to define a non-zero shear angle (φ).