Not applicable.
This invention was not made as part of a federally sponsored research or development project.
The present disclosure relates generally to adjustable thickness slicers and, more particularly, to food product slicers and the components associated with adjusting a gauge plate.
Typical reciprocating slicers have a rotatable, circular or disc-like slicing blade, an adjustable gauge plate for determining the thickness of the slice and a carriage for supporting the product as it is moved back and forth past the cutting edge of the knife during slicing. The gauge plate is situated along the edge of the knife toward the front of a slicing stroke and is laterally movable with respect to the knife for determining the thickness of the slices to be cut. A mechanism such as an adjustment handle for setting a spacing between the plane of the gauge plate surface and the plane of the knife edge for the purpose of slicing is also typically provided so that operators can select a thickness of slices to be produced. Movement of the gauge plate is generally a linear movement of the plane of the gauge plate relative to the plane of the knife edge. Thus, movement of the adjustment handle moves the gauge plate in a manner to make slice thickness adjustments.
Conventional gauge plate adjustment systems are plagued by backlash, or the ability to rotate the adjustment handle without producing any movement of the gauge plate, as well as coarse adjustability control when the gauge plate is nearest the plane of the knife, where it would ideally offer the finest adjustability control. Embodiments of the present invention address these weaknesses of conventional gauge plate adjustment systems.
A product slicer having an adjustable gauge plate precisely positioned by the unique cooperation of a cam plate and a cam follower.
Without limiting the scope of the present invention as claimed below and referring now to the drawings and figures:
These drawings are provided to assist in the understanding of the exemplary embodiments of the invention as described in more detail below and should not be construed as unduly limiting the invention. In particular, the relative spacing, positioning, sizing and dimensions of the various elements illustrated in the drawings are not drawn to scale and may have been exaggerated, reduced or otherwise modified for the purpose of improved clarity. Those of ordinary skill in the art will also appreciate that a range of alternative configurations have been omitted simply to improve the clarity and reduce the number of drawings.
The present invention enables a significant advance in the state of the art. The preferred embodiments of the invention accomplish this by new and novel arrangements of elements, materials, relationships, and methods that are configured in unique and novel ways and which demonstrate previously unavailable but preferred and desirable capabilities. The description set forth below in connection with the drawings is intended merely as a description of the presently preferred embodiments of the invention, and is not intended to represent the only form in which the present invention may be constructed or utilized. The description sets forth the designs, materials, functions, means, and methods of implementing the invention in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions, features, and material properties may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the invention. The present disclosure is described with reference to the accompanying drawings with preferred embodiments illustrated and described. The disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Like numbers refer to like elements throughout the disclosure and the drawings. In the figures, the thickness of certain lines, layers, components, elements or features may be exaggerated for clarity. Broken lines illustrate optional features or operations unless specified otherwise. All publications, patent applications, patents, and other references mentioned herein are incorporated herein by reference in their entireties.
In addition to the housing (200) the product slicer (100) has a circular knife (300) mounted to the housing (200) which rotates about a knife axis (310) located in the center of the knife (300). Additionally, the knife (300) has a knife cutting edge (320) that is located around the knife's (300) perimeter which defines a knife cutting plane. The knife (300) may be covered by a knife cover (330), as seen in
The product slicer (100) has a carriage assembly (400) is configured for reciprocating motion past the knife cutting edge (320) and is slidably attached by a carriage assembly arm (420) to the housing (200). The carriage assembly (400) may include a carriage assembly handle (410) which provides a hold point for the end user, as seen in
The variability of product slice thickness is obtained through the use of an adjustable gauge plate (500), which in some embodiments has a gauge plate mount (510) and a gauge plate mount nut (520). The gauge plate mount (510) joins the adjustable gauge plate (500) to a slider assembly (900), which may have a cooperating gauge plate receiver (940), as illustrated in
Now referring to
The gauge plate (500) may have a gauge plate bearing surface (530) onto which sliceable product rest while cradled in the carriage assembly (400). The bearing surface (530) need not be flat. Furthermore, the gauge plate (500) is configured so that the gauge plate bearing surface (530) is substantially parallel to the knife cutting plane. Additionally, the adjustable gauge plate (500) is adjustable in an adjustment direction, which in the figures is parallel to the knife axis (310), from a gauge plate initial position, with the gauge plate bearing surface (530) that is substantially in the knife cutting plane, to a gauge plate (500) slicing position where the gauge plate bearing surface (530) is offset from the knife cutting plane. The adjustment direction need not be parallel to the knife axis (310). The gauge plate (500) slicing position is not limited to one specific thickness but can be varied based upon the sliceable product and its intended use. For instance, a ham may be sliced in a thickness of less than half of a millimeter to created what is called shredded ham; the ham may be sliced at 1 to 3 millimeters to create sandwich slices; additionally, the ham may be sliced at 7 millimeters or more to created ham steaks.
In order to adjust the gauge plate (500) with respect to knife cutting plane, the product slicer (100) has an adjustment handle (600) rotably mounted to the housing (200), as seen in
Now referring to
Now with reference to
Now referring to
Tables 1 and 2 below illustrate an embodiment of the relationship of the initial head-to-cam-center distance (862) and the slicing head-to-cam-center distance (872), for various rotations of the cam plate (700). The delta (Δ) column for each specific rotation value of the cam plate (700) is the initial head-to-cam-center distance (862) minus the slicing head-to-cam-center distance (872). The delta (Δ) values are always positive because the cam follower (800) moves from the initial cam head position (860), toward the cam plate center axis (760), to the slicing cam head position (870), unlike traditional systems that move in the opposite direction at the sacrifice of performance and fine-tuning control. In another embodiment in which adjustment handle (600) and the cam plate (700) are directly connected in a 1:1 relationship, Tables 1 and 2 below illustrate an embodiment of the relationship of the initial head-to-cam-center distance (862) and the slicing head-to-cam-center distance (872), for various rotations of the adjustment handle (600).
An advantage of this unique configuration is that a significant rotation of the cam plate (700), or adjustment handle (600), is required to produce a meaningful displacement of the adjustable gauge plate (500) from the gauge plate initial position to the gauge plate slicing position. In some embodiments the delta (Δ) value, which is the difference between the initial head-to-cam-center distance (862) and the slicing head-to-cam-center distance (872), directly correlates to the change in distance of the adjustable gauge plate (500) from the gauge plate initial position to the gauge plate slicing position. In one particular embodiment rotation of the adjustment handle (600) through any 45 degrees produces a change from the gauge plate initial position to the gauge plate slicing position of no more than 0.100 inch, and results in the slicing head-to-cam-center distance (872) being 2-8% less than the initial head-to-cam-center distance (862); and a further embodiment produces a change from the gauge plate initial position to the gauge plate slicing position of no more than 0.080 inch, and results in the slicing head-to-cam-center distance (872) being 3-6% less than the initial head-to-cam-center distance (862). In a further embodiment rotation of the adjustment handle (600) through any 90 degrees produces a change from the gauge plate initial position to the gauge plate slicing position of no more than 0.200 inch, and results in the slicing head-to-cam-center distance (872) being 4-16% less than the initial head-to-cam-center distance (862); and a further embodiment produces a change from the gauge plate initial position to the gauge plate slicing position of no more than 0.160 inch, and results in the slicing head-to-cam-center distance (872) being 6-12% less than the initial head-to-cam-center distance (862). In yet an even further embodiment wherein rotation of the adjustment handle (600) through any 180 degrees produces a change from the gauge plate initial position to the gauge plate slicing position of no more than 0.400 inch, and results in the slicing head-to-cam-center distance (872) being 8-32% less than the initial head-to-cam-center distance (862); and a further embodiment produces a change from the gauge plate initial position to the gauge plate slicing position of no more than 0.320 inch, and results in the slicing head-to-cam-center distance (872) being 12-24% less than the initial head-to-cam-center distance (862).
The relative change in position of the cam plate (700) to the cam follower (800) from the initial cam head position (860) to the slicing cam head position (870) is a travel length (880), illustrated in
As seen in Table 3, in this embodiment the initial cam head position (860) is at 0 degrees and has an initial head-to-cam-center distance (862) of 1.748″. Once the cam plate (700) has rotated 2.5 degrees to a first slicing cam head position (870), a first slicing head-to-cam-center distance (872) is 1.744″, and therefore a first delta (Δ) value is a positive 0.004″, meaning that the rotation of the cam plate (700) results in the cam follower (800) moving closer to the cam plate center axis (760). Additionally, the relative motion of the center of the cam follower (800) and the cam plate (700) results in a first travel length (880) of 0.076″, which produces a first travel-delta ratio of 19.00 and a first travel-rotation ratio of 0.030. Similarly, once the cam plate (700) has rotated 5 degrees to a second slicing cam head position (870), a second slicing head-to-cam-center distance (872) is 1.739″, and therefore a second delta (Δ) value is a positive 0.009″. Additionally, the relative motion of the center of the cam follower (800) and the cam plate (700) results in a second travel length (880) of 0.152″, which produces a second travel-delta ratio of 16.89 and a second travel-rotation ratio of 0.030. Likewise, once the cam plate (700) has rotated 7.5 degrees to a third slicing cam head position (870), a third slicing head-to-cam-center distance (872) is 1.735″, and therefore a third delta (Δ) value is a positive 0.013″. Additionally, the relative motion of the center of the cam follower (800) and the cam plate (700) results in a third travel length (880) of 0.228″, which produces a third travel-delta ratio of 17.54 and a third travel-rotation ratio of 0.030. Finally, once the cam plate (700) has rotated 10 degrees to a fourth slicing cam head position (870), a fourth slicing head-to-cam-center distance (872) is 1.731″, and therefore a fourth delta (Δ) value is a positive 0.017″. Additionally, the relative motion of the center of the cam follower (800) and the cam plate (700) results in a fourth travel length (880) of 0.304″, which produces a fourth travel-delta ratio of 17.88 and a fourth travel-rotation ratio of 0.030.
As previously touched upon, in some embodiments preferential control is achieved when the delta (Δ) value is a positive, the travel-delta ratio is high, or when an travel-rotation ratio is high, or a combination thereof. To appreciate the meaning of a high travel-delta ratio or a high travel-rotation ratio one must take a cursory look at embodiments wherein the delta (Δ) value is negative, meaning that rotation of the cam plate (700) causes the cam follower (800) to move away from the cam plate center axis (760) as the cam follower (800) goes from the initial cam head position (860) to the slicing cam head position (870), as seen in
As seen in Table 4, in this negative delta (Δ) value embodiment the initial cam head position (860) is at 0 degrees and has an initial head-to-cam-center distance (862) of 0.334″. Once the cam plate (700) has rotated 2.5 degrees to a first slicing cam head position (870), a first slicing head-to-cam-center distance (872) is 0.339″, and therefore a first delta (Δ) value is a negative 0.005″, meaning that the rotation of the cam plate (700) results in the cam follower (800) moving away from the cam plate center axis (760). Additionally, the relative motion of the center of the cam follower (800) and the cam plate (700) results in a first travel length (880) of 0.0129″, which produces a first travel-delta ratio of −2.58 and a first travel-rotation ratio of 0.0052. Comparing these values with those of the positive delta (Δ) value embodiment of Table 3 illustrates that the same 2.5 degrees of cam plate (700) rotation yields (a) a first travel length (880) in Table 3 that is 5.89 times greater than the first travel length (880) in Table 4, (b) a first travel-delta ratio in Table 3 that is 7.36 times greater than the first travel-delta ratio in Table 4, and (c) a first travel-rotation ratio in Table 3 that is 5.77 times greater than the first travel-rotation ratio in Table 4. For the sake of brevity a similar discussion of the values at 5 degrees, 7.5 degrees, and 10 degrees of rotation in Table 4 is omitted.
In a first series of positive delta (Δ) value embodiments preferred control is achieved when the first 10 degrees of rotation of the cam plate (700) from the initial cam head position (860) has a travel length (880) that is at least 0.075″, while in a further embodiment it is at least 0.150″, and in an even further embodiment it is at least 0.225″. In a further series of embodiment the first 10 degrees of rotation of the cam plate (700) from the initial cam head position (860) also produces a travel length (880) that is less than 0.600″, while in a further embodiment it is less than 0.500″, and in an even further embodiment it is less than 0.400″.
In a second series of positive delta (Δ) value embodiments preferred control is achieved when the first 10 degrees of rotation of the cam plate (700) from the initial cam head position (860) has an travel-delta ratio that is positive and at least 3.0 throughout the entire 10 degree range, while in a further embodiment it is at least 5.0, and in an even further embodiment it is at least 10.0. In a further series of embodiments the first 10 degrees of rotation of the cam plate (700) from the initial cam head position (860) has an travel-delta ratio that is positive and less than 40, while in a further embodiment it is less than 30, and in an even further embodiment it is less than 25.
In a third series of positive delta (Δ) value embodiments preferred control is achieved when the first 10 degrees of rotation of the cam plate (700) from the initial cam head position (860) has an travel-rotation ratio that is at least 0.010 throughout the entire 10 degree range, while in a further embodiment it is at least 0.015, and in an even further embodiment it is at least 0.020. In a further series of embodiments the first 10 degrees of rotation of the cam plate (700) from the initial cam head position (860) has an travel-rotation ratio that is less than 0.100, while in a further embodiment it is less than 0.075, and in an even further embodiment it is less than 0.050.
In additional embodiments the relationships of the travel-rotation ratio and the travel-delta ratio disclosed with respect to “throughout the entire 10 degree range”, are also true throughout at least 45 degrees, and throughout at least 90 degrees in further embodiments, and throughout at least 180 degrees in even further embodiments, and throughout at least 360 degrees in a final series of embodiments.
In a fourth series of positive delta (Δ) value embodiments preferred control is achieved when for the first 45 degrees of rotation of the cam plate (700) from the initial cam head position (860), each slicing head-to-cam-center distance (872) is at least 25% of the cam plate diameter (710), while it is at least 30% in another embodiment, and at least 35% in yet another embodiment. In a fifth series of positive delta (Δ) value embodiments preferred control is achieved when for the first 90 degrees of rotation of the cam plate (700) from the initial cam head position (860), each slicing head-to-cam-center distance (872) is at least 25% of the cam plate diameter (710), while it is at least 30% in another embodiment, and at least 35% in yet another embodiment. In a sixth series of positive delta (Δ) value embodiments preferred control is achieved when for the first 180 degrees of rotation of the cam plate (700) from the initial cam head position (860), each slicing head-to-cam-center distance (872) is at least 20% of the cam plate diameter (710), while it is at least 25% in another embodiment, and at least 30% in yet another embodiment.
Such embodiments having long travel lengths (880) compared to the rotation of the cam plate (700), and thus the difference from the initial head-to-cam-center distance (862) to the slicing head-to-cam-center distance (872), or delta (Δ) value, and the criticality of the associated ranges and ratios, produce unexpected performance improvements characterized by finer and more accurate control, with reduced backlash and improved repeatability, in part because for a particular angular rotation of the cam plate (700) the travel length (880) is significantly increased over conventional systems, which is apparent when comparing
One embodiment obtains such performance improving relationships through the use of a cam plate channel (740), as seen in
Additional performance improvements are achieved with embodiments incorporating unique cooperating geometries of the cam plate channel (740), or cam plate projection (780), and the cam follower (800) to further promote smooth operation and reduce backlash. Such cooperating geometries provide improved performance of both positive delta (Δ) value embodiments, such as that seen in
Conversely, conventional straight walled cam plate channels and a pin-type cam follower suffer from wear to the cam plate channel and cam follower resulting in unwanted movement, or more precisely lack of movement—also referred to as backlash, in the gauge plate (500) due to additional play, or slop, between the cam plate channel and pin-type cam follower. Such conventional systems have a gap between the straight walled cam plate channels and the pin-type cam follower from the outset, and the gap increases overtime with use thereby increasing the undesirable attributes that plague such systems. In the current embodiment, wear to the cam plate channel (740) and cam follower head (810) reduces or eliminates backlash thereby producing movement in the gauge plate (500) with any rotation of the adjustment handle (600). As the surfaces of the cam plate channel (740) and/or cam follower head (810) wear, the pitched configuration of the cam plate channel (740) walls and cam follower head (810) compensate.
In a further embodiment the cam plate channel (740) has a first channel sidewall (742), with at least a portion oriented at a first sidewall angle (743) greater than five degrees, and a second channel sidewall (744), with at least a portion oriented at a second sidewall angle (745) greater than five degrees. In still a further embodiment at least a portion of the cam follower head (810) has a cam follower pitch (818) that is within 2.5 degrees of the first sidewall angle (743) and the second sidewall angle (745). The combination of a cam plate channel (740) having pitched sidewalls (742, 744) and the mating cam follower head (810) having with a cam follower pitch (818) that is within 2.5 degrees of the first sidewall angle (743) and the second sidewall angle (745) allows for the compensation of cam plate channel (740) and cam follower head (810) wear and further reduces backlash. A still further embodiment incorporates a cam plate channel (740) with at least a portion oriented at a first sidewall angle (743) of 5-45 degrees, and at least a portion oriented at a second sidewall angle (745) of 5-45 degrees. Likewise, in this embodiment, the cam follower (800) has a cam follower head (810) with at least a portion of the cam follower head (810) having an angled head surface oriented at a cam follower pitch (818) of 5-45 degrees to further compensate for wear of the cam plate channel (740) and cam follower (800). Another embodiment has a cam plate channel (740) with a first channel sidewall (742) having at least a portion oriented at a first sidewall angle (743) of 10-45 degrees, and a second channel sidewall (744) having at least a portion oriented at a second sidewall angle (745) of 10-45 degrees, as well as a cam follower (800) having a cam follower head (810) with at least a portion of the cam follower head (810) having an angled head surface oriented at a cam follower pitch (818) of 10-45 degrees. Still further, another embodiment has a cam plate channel (740) with a first channel sidewall (742) having at least a portion oriented at a first sidewall angle (743) of 15-45 degrees, and a second channel sidewall (744) having at least a portion oriented at a second sidewall angle (745) of 15-45 degrees, as well as a cam follower head (810) with at least a portion of the cam follower head (810) having an angled head surface oriented at a cam follower pitch (818) of 15-45 degrees; while another embodiment has a cam plate channel (740) with a first channel sidewall (742) having at least a portion oriented at a first sidewall angle (743) of 20-30 degrees, and a second channel sidewall (744) having at least a portion oriented at a second sidewall angle (745) of 20-30 degrees, as well as a cam follower head (810) with at least a portion of the cam follower head (810) having an angled head surface oriented at a cam follower pitch (818) of 20-30 degrees.
Now with reference to
In one embodiment the channel exterior width (748) is no more than 15% of the cam plate diameter (710), and the channel depth (752) of
All of the previously described performance improvements achieved via the unique cooperating geometries of the cam plate channel (740) are also applicable to the cam plate projection (780) and the cam follower (800), as seen in
In one embodiment the cam follower first channel sidewall (842) has at least a portion with a cam follower first sidewall angle (843) greater than zero, and the cam follower second channel sidewall (844) has at least a portion with a cam follower second sidewall angle (845) greater than zero. Further, the cam plate projection (780) may have a portion with an angled projection surface oriented at a cam plate projection pitch (788) that is greater than zero. The combination of a cam follower (800) having pitched sidewalls (842, 844) and the mating cam plate projection (780) having with a corresponding cam plate projection pitch (788) allows for the compensation for wear and reduction of backlash. In the current embodiment, wear to the cam plate projection (780) and/or the cam follower (800) does not result in unwanted movement in the gauge plate (500). As the surfaces of the cam plate projection (780) and/or cam follower (800) wear, the pitched configuration of the sidewalls (842, 844) and the corresponding cam plate projection pitch (788) compensate.
In a further embodiment at least a portion of the cam follower first channel sidewall (842) is oriented at a cam follower first sidewall angle (843) of greater than five degrees, and at least a portion of the cam follower second channel sidewall (844) is oriented at a cam follower second sidewall angle (845) of greater than five degrees. In still a further embodiment at least a portion of the cam plate projection (780) has a cam plate projection pitch (788) that is within 2.5 degrees of the cam follower first sidewall angle (843) and the cam follower second sidewall angle (845). In a further embodiment at least a portion of the cam follower first channel sidewall (842) is oriented at a cam follower first sidewall angle (843) of 5-45 degrees, and at least a portion of the cam follower second channel sidewall (844) is oriented at a cam follower second sidewall angle (845) of 5-45 degrees. Likewise, in this embodiment, at least a portion of the cam plate projection (780) has a cam plate projection pitch (788) of 5-45 degrees. Another embodiment has at least a portion of the cam follower first channel sidewall (842) is oriented at a cam follower first sidewall angle (843) of 10-45 degrees, and at least a portion of the cam follower second channel sidewall (844) is oriented at a cam follower second sidewall angle (845) of 10-45 degrees. Likewise, in this embodiment, at least a portion of the cam plate projection (780) has a cam plate projection pitch (788) of 10-45 degrees. Still further, another embodiment has at least a portion of the cam follower first channel sidewall (842) is oriented at a cam follower first sidewall angle (843) of 15-45 degrees, and at least a portion of the cam follower second channel sidewall (844) is oriented at a cam follower second sidewall angle (845) of 15-45 degrees. Likewise, in this embodiment, at least a portion of the cam plate projection (780) has a cam plate projection pitch (788) of 15-45 degrees; while another embodiment has a cam follower first sidewall angle (843) of 20-30 degrees, and a cam follower second sidewall angle (845) of 20-30 degrees. Likewise, in this embodiment, at least a portion of the cam plate projection (780) has a cam plate projection pitch (788) of 20-30 degrees.
With continued reference to
Wear accommodation, and backlash reduction, may be further reduced in embodiments incorporating a cam-to-follower biasing mechanism (1000) to bias the cam follower head (810) and the cam plate (700) against one another, as seen in
Smooth operation is further achieved in some embodiment through the use of dissimilar materials for the cam plate (700) and the cam follower (800) to further control where the wear occurs, achieve greater reduction of friction in the system, and improved durability. In one such embodiment at least one of the cam plate (700) and the cam follower (800) are formed of metallic material, and one of the cam plate (700) and the cam follower (800) are formed of non-metallic material. In one particular embodiment majority of the cam plate (700) is formed of a non-metallic material and the portion of the cam follower (800) in contact with the cam plate (700) is formed of a metallic material.
In one embodiment the non-metallic component is formed of a non-metallic material having a non-metallic material density of less than 2 grams per cubic centimeter and a tensile modulus of at least 4500 MPa (ISO 527-1/-2 test standard); while in a further embodiment the non-metallic material density of less than 1.5 grams per cubic centimeter and a tensile modulus of at least 5000 MPa (ISO 527-1/-2 test standard). In yet a further embodiment the non-metallic material has a non-metallic material tensile strength of at least 85 megapascal (ISO 527-1/-2 test standard), and a non-metallic material strain at break of at least 3.0% (ISO 527-1/-2 test standard); while in an even further embodiment the non-metallic material tensile strength of at least 90 megapascal (ISO 527-1/-2 test standard), and a non-metallic material strain at break of at least 4.0% (ISO 527-1/-2 test standard). In yet a further embodiment the non-metallic component tensile modulus is at least 2 percent of metallic component tensile modulus and the metallic material density is at least 3 times the non-metallic material density. In an even further embodiment a strain ratio of the metallic material strain at break to the non-metallic material strain at break is less than 25, while in an even further embodiment the strain ratio is less than 20. Conventional thinking would be to make the non-metallic component as strong as possible, which leads to a part formed of material having a high ultimate tensile strength, but one that is generally plagued by a strain at break of 2.5% or less, leading to a large strain ratio and resulting in durability issues. Focusing on unique strain relationships, rather than simply ultimate tensile strength, provide enhanced durability. Such a multi-material interface possessing these unique relationships among the materials achieves the desired durability and wear control, while promoting smooth operation of the interface.
In one embodiment the metallic component is formed of a metallic material having a metallic material density of greater than 4 grams per cubic centimeter and a tensile modulus of at least 150 GPa (ISO 527-1/-2 test standard); while in a further embodiment the metallic material density of at least 6 grams per cubic centimeter and a tensile modulus of at least 175 GPa (ISO 527-1/-2 test standard). In yet a further embodiment the metallic material has a metallic material tensile strength of at least 400 megapascal, and a metallic material strain at break of at least 50%; while in an even further embodiment the metallic material tensile strength of at least 450 megapascal, and a metallic material strain at break of at least 60%.
In a further embodiment the non-metallic component material includes a lubricating agent so that the non-metallic component is self-lubricating. In one embodiment the non-metallic component has a specific wear rate against steel of less than 10 (10−6 mm−3/Nm), wherein the specific wear rate was measured at low speed (0.084 m/s) with a contact pressure of 0.624 MPa in a reciprocating motion (total sliding distance: 4.25 km), while in a further embodiment the non-metallic component has a specific wear rate against steel of less than 7 (10−6 mm−3/Nm), and in an even further embodiment the non-metallic component has a specific wear rate against steel of less than 4 (10−6 mm−3/Nm). In another embodiment the non-metallic component material has a dynamic coefficient of friction against steel is less than 0.50, wherein the coefficient of friction was measured at a high speed (0.5 m/s) with a load of 10 N in a sliding motion (Block-on-Ring), while in a further embodiment the dynamic coefficient of friction against steel is less than 0.40, and less than 0.30 in an even further embodiment.
In one embodiment the non-metallic component is an engineering thermoplastic. In another embodiment the non-metallic component is composed primarily of a material selected from polyoxymethylene (POM), poly(methyl methacrylate) (PMMA), acrylonitrile butadiene styrene (ABS), polyamide, polylactic acid (polylactide), polybenzimidazole (PBI), polycarbonate (PC), polyether sulfone (PES), polyether ether ketone (PEEK), polyetherimide (PEI), polyethylene (polyethene, polythene, PE), polyphenylene oxide (PPO), polyphenylene sulfide (PPS), polypropylene (PP), polystyrene, polyvinyl chloride (PVC), polybutylene terephthalates (PBT), thermoplastic polyurethane (TPU), and semi-crystalline engineering resin systems that meet the claimed mechanical properties. In one embodiment the non-metallic material is a polyoxymethylene (POM) homopolymer, which in a further embodiment is an acetal resin. Further, the non-metallic material may be fiber reinforced. In one such embodiment the non-metallic material includes at least 5% fiber reinforcement. In one such embodiment the fiber reinforcement includes long-glass fibers having a length of at least 10 millimeters pre-molding and produce a finished component having fiber lengths of at least 3 millimeters, while another embodiment includes fiber reinforcement having short-glass fibers with a length of at least 0.5-2.0 millimeters pre-molding. Incorporation of the fiber reinforcement increases the tensile strength of the component, however it may also reduce the strain at break therefore a careful balance must be struck to maintain sufficient elongation and ensure durability of the non-metallic component. Therefore, one embodiment includes less than 50% fiber reinforcement, while in an even further embodiment has 5-40% fiber reinforcement, and yet another embodiment has 10-30% fiber reinforcement. Long fiber reinforced non-metallic materials, and the resulting melt properties, produce a more isotropic material than that of short fiber reinforced non-metallic materials, primarily due to the three-dimensional network formed by the long fibers developed during injection molding. Another advantage of long-fiber material is the almost linear behavior through to fracture resulting in less deformation at higher stresses.
Some examples of metals and metal alloys that can be used to form the metallic component include, without limitation, magnesium alloys, aluminum/aluminum alloys (e.g., 3000 series alloys, 5000 series alloys, 6000 series alloys, such as 6061-T6, and 7000 series alloys, such as 7075), titanium alloys (e.g., 3-2.5, 6-4, SP700, 15-3-3-3, 10-2-3, or other alpha/near alpha, alpha-beta, and beta/near beta titanium alloys), carbon steels (e.g., 1020 or 8620 carbon steel), stainless steels (e.g., 304, 410, 416 stainless steel), PH (precipitation-hardenable) alloys (e.g., 17-4, C450, or C455 alloys), copper alloys, and nickel alloys. Some examples of polymers that can be used to form the non-metallic component include, without limitation, thermoplastic materials (e.g., polyethylene, polypropylene, polystyrene, acrylic, PVC, ABS, polycarbonate, polyurethane, polyphenylene oxide (PPO), polyphenylene sulfide (PPS), polyether block amides, nylon, and engineered thermoplastics), thermosetting materials (e.g., polyurethane, epoxy, and polyester), copolymers, and elastomers (e.g., natural or synthetic rubber, EPDM, and compounds thereof). In one particular embodiment the metallic material has Rockwell hardness value of at least 25, while a further embodiment has a Rockwell hardness value of at least 28, while an even further embodiment has a Rockwell hardness value of 30-40, thereby further promoting smooth operation of the interface and desired wear tendencies.
Numerous alterations, modifications, and variations of the preferred embodiments disclosed herein will be apparent to those skilled in the art and they are all anticipated and contemplated to be within the spirit and scope of the instant invention. For example, although specific embodiments have been described in detail, those with skill in the art will understand that the preceding embodiments and variations can be modified to incorporate various types of substitute and or additional or alternative materials, relative arrangement of elements, and dimensional configurations. Accordingly, even though only few variations of the present invention are described herein, it is to be understood that the practice of such additional modifications and variations and the equivalents thereof, are within the spirit and scope of the invention as defined in the following claims. The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or acts for performing the functions in combination with other claimed elements as specifically claimed.