FIELD
The present disclosure relates to shot blast equipment and more particularly to shot blasting assemblies with wheels and replaceable vanes.
BACKGROUND
This Background is intended to introduce various aspects of the art, which may be associated with the present disclosure to thereby assist in providing a framework to facilitate a better understanding of particular aspects of the present disclosure. Accordingly, it should be understood that this Background should be read in this light, and not necessarily as admissions of prior art.
Shot blasting is commonly used to alter surface characteristics of metal parts. The shot blasting process typically involves rotating a wheel with vanes attached thereto at high speeds such that abrasive media, such as shot (small spheres), grit (angular pieces), or other abrasive media, is introduced at or near the center of the wheel are accelerated and propelled by the vanes into contact with one or more surfaces of the part. The shot impacts the surfaces and thereby textures, peens, smooths, and/or removes contaminants from the surface. The vanes and other internal parts of the blast wheel assembly are normal wear parts that may require frequent replacement
SUMMARY
This Summary is provided to introduce a selection of concepts that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter.
In certain examples, a blasting assembly includes a wheel that is rotatable about a first axis. The wheel defines a hole centered about the first axis and at least one radially extending slot that has an open first slot end that faces the hole and a second slot end that is opposite the first slot end and is at least partially closed. A vane is configured to be received into each radially extending slot such that each vane is retained in a radially extending slot as the wheel is rotated and configured to propel media. The vane includes a body radially extending between a first vane end and a second vane end, and the body extending between a first flange and a second flange, and having opposing vane side surfaces. An attachment portion integral with the second flange, and the attachment portion configured to be received into the slot. The attachment portion has a first vane end retaining surface and a second vane end retaining surface that abut the second slot end. The first vane end retaining surface and the second vane end retaining surface are adjacent to each other, the first vane end retaining surface is convex, and the second vane end retaining surface is concave.
In certain examples, a vane for insertion into a slot of a wheel of a blasting assembly such that the vane propels media as the wheel is rotated includes a body radially extending between a first vane end and a second vane end, between a first flange and a second flange, and having opposing vane side surfaces. An attachment portion integral with the second flange, the attachment portion configured to be received into the slot, and the attachment portion has a first vane end retaining surface and a second vane end retaining surface that are configured to abut the wheel. The first vane end retaining surface and the second vane end retaining surface are adjacent to each other, the first vane end retaining surface is convex, and the second vane end retaining surface is concave.
Various other features, objects, and advantages will be made apparent from the following description taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The present disclosure is described with reference to the following Figures. The same numbers are used throughout the Figures to reference like features and like components.
FIG. 1 is a perspective view of an example assembly including a wheel and a plurality of vanes coupled to the wheel.
FIG. 2 is a perspective view of the assembly depicted in FIG. 1 with the vanes decoupled and removed from the wheel. Note that FIG. 2 depicts one vane positioned adjacent to a slot of the wheel.
FIG. 3 is a perspective view of an example wheel according to the present disclosure.
FIGS. 4-7 are enlarged perspective views of an example slot in the wheel depicted in FIG. 3.
FIG. 8 is a perspective cross-section view of an example slot along line 8-8 on FIG. 3.
FIG. 9 is a cross-sectional view opposite line 8-8 of an example slot of the wheel depicted in FIG. 3.
FIGS. 10-12 are perspective view of an example vane according to the present disclosure.
FIG. 13 is a side view of an example vane according to the present disclosure.
FIG. 14 is a cross-sectional view of the vane of FIG. 13 along line 14-14.
FIG. 15 is a cross-sectional view of the vane of FIG. 13 along line 15-15.
FIG. 16 is a graphical stress model of forces applied to a known vane when the vane is coupled to a wheel.
DETAILED DESCRIPTION
FIGS. 1-2 depict an example shot blasting assembly 10. The assembly 10 includes a wheel 12 and a plurality of blades or vanes 13. Note that FIG. 1 depicts eight vanes 13 coupled to the wheel 12, and FIG. 2 depicts one vane 13 adjacent to one of several slots in the wheel 12. The assembly 10 is for accelerating abrasive media through rotation about a central axis 14, including but not limited to shot, grit, and cut wire, that contact a surface of a part (not depicted). The abrasive material impacting the surface of the part being worked to thereby modify the surface and/or finish the part (e.g., roughen, shape/curve, smooth, shot peen, induce compressive stress, harden, or remove contaminants). During operation of the assembly 10 (described briefly below), the abrasive material wears (e.g., erodes) the vanes, and thus, the vanes 13 must be periodically replaced. In addition, the forces (e.g., centrifugal force and acceleration during startup) exerted on the vanes 13 while the wheel 12 spins may cause damage to the vanes 13. For instance, forces may be concentrated in a small area of the vane 50 that contacts the surfaces of the wheel 12 and thus, the concentrated forces may cause failure of the vanes 13 (e.g., cracks form in the vanes 13). FIG. 16 depicts a graphical stress model of forces applied to a vane 13 when the vane 13 is coupled to a wheel 12 (e.g., of FIG. 1). The stresses affecting the vane 13 are depicted as a plurality of dots such that a high concentration of dots equates to areas of the vane 13 subjected to high stress. For instance, area Z1 has a high concentration of dots and thus large amounts of stress affect this area Z1 of the vane 13. In contrast, the areas Z2 have low concentration of dots and thus, smaller amounts of stress affect these areas Z2 of the vane 13. Failure of the vane 13 often occurs in the area Z1 of large stresses. Also, note that vanes 13 can also be damaged when they are removed from the wheel 12. In one instance, forceable contact (e.g., strikes of a hammer) is required to unseat the attachment portion of the vane 13 from the wheel 12 and such contact may damage the vanes 13. Furthermore, the abrasive material or debris may accumulate between the surfaces of the vane 13 and the surfaces of the wheel 12 thereby preventing the vane 13 from being easily removed. This is commonly referred to as “shot locking” of the vane 13 to the wheel 12.
Through research and experimentation, the present inventors have endeavored to develop improved assemblies that reduce and/or minimize problems associated with the centrifugal abrasive blasting process and maintenance thereof, some of which are noted above. The present inventors also further endeavored to increase the life of vanes and prevent damage to the vanes during operation and when being coupled to or decoupled from the wheel. Thus, the present inventors have developed the assemblies 19 of the present disclosure including new wheels 20 and vanes 50, as described herein below.
FIG. 3 depicts an example centrifugal blasting assembly 19 of the present disclosure. The assembly 19 includes a wheel 20 with an example vane 50 coupled thereto. Note that the vane 50 is depicted schematically in dashed lines and a plurality of vanes 50 are coupled to the wheel 20.
The wheel 20 has a center hole 21 and a center rotational axis 22 extending therethrough about which the wheel 20 is rotated. A shaft (not depicted) coupled to a hub (not depicted) of a shot blasting machine (not depicted) attaches to the bottom of wheel 20, and the rotating shaft (not depicted) drives rotation of the wheel 20 about the axis 22. Accordingly, as the wheel 20 is rotated, abrasive material, such as shot or small spheres, are introduced near the center hole 21 and the rotating vanes 50 accelerate the abrasive material in a direction toward the exterior perimeter 26 of the wheel 20. The wheel 20 also includes an exterior perimeter surface 24 at the exterior perimeter 26 and an opposite interior perimeter 27 and interior perimeter surface 23. The wheel has an interior perimeter surface 23 and an opposite exterior perimeter surface 24. The wheel 20 also has an exterior surface 25.
Referring now to FIGS. 4-9, the wheel 20 has a plurality of mounting slots 28 that are each configured to receive an attachment portion 60 of the vane 50 (see FIG. 10). The slots 28 are recessed into the wheel 20 (e.g., the slots 28 are recessed axially below the exterior surface 25). Each slot 28 is configured to retain a vane 50 on the wheel 20 during operation of the assembly 19 and rotation of the wheel 20.
Each slot 28 is at least partially defined by a pair of opposing slot flanges 29 such that a channel 33 is defined therebetween and the slot flanges 29 help retain the vanes 50 in the slots 29. Side flange surfaces 30 of the slot flanges 29 face each other and a channel 33 is located between the side flange surfaces 30. Each slot flange 29 has a first flange thickness 31 (FIG. 9) at the interior perimeter 27 and a second flange thickness 32 (FIG. 9) near the at least partially closed second slot end 34 of the slot 28. The second flange thickness 32 is greater than the first flange thickness 31, and thickness of the slot flange 29 tapers or narrows in a direction from the interior perimeter 27 to the closed exterior perimeter 26, from the second slot end 34 to the first slot end 35, or axial in a direction away from the first axis 22 (see arrow A on FIG. 9).
Each slot flange 29 also has an underside slot flange retaining surface 37 that is opposite the exterior surface 25, and the wheel 20 has several other retaining surfaces positioned around the slot 28 such as opposing slot side retaining surfaces 38, a slot lower retaining surface 39, and a slot end retaining surface 40 (See FIG. 8). Note that curved slot transition surfaces 48 with rounded or chamfered edges are between the retaining surfaces 37, 38, 39, 40. In other examples, an angular edge is between the surfaces 37, 38, 39, 40.
Each slot side retaining surface 38 has a first side surface width 41 (FIG. 9) at the interior perimeter 27 and a second side surface width 42 (FIG. 9) at the second slot end 34 of the slot 28. The first side surface width 41 is greater than the second side surface width 42, and width of the slot flange 29 tapers in a direction from the interior perimeter 27 to the second slot end 34 (see arrow B on FIG. 9). The slot side retaining surfaces 38 face each other and converge toward each other. For example, the distance (see arrows D3 and D4 on FIG. 6) between the slot side retaining surfaces 38 decreases in a direction from the interior perimeter 27 to the second slot end 34 (see arrow B on FIG. 9).
The slot end retaining surface 40 is at the second slot end 34 of the slot 28 and extends between the slot side retaining surfaces 38 (see FIG. 6). The slot end retaining surface 40 has a first section 44A that is curved. In certain examples, the first section 44A has a concave shape. The slot end retaining surface 40 also has a second section 44B that is curved in a radial direction away from the axis 22 (see arrow A on FIG. 8) of the wheel 20 (see also FIG. 3). In certain examples, the first section 44A extends along a radius of 0.1875 inches. In certain examples, the first section 44A has a radius in the range of 0.100-0.300 inches. An upper slot surface 45 is at the second slot end 34 of the slot 28 and is in a plane that is offset from the plane in which the exterior surface 25 extends (see FIG. 8).
The slot lower retaining surface 39 extends between the slot side retaining surfaces 38 and the slot end retaining surface 40 (see FIG. 6). The slot lower retaining surface 39 is generally planar. The slot lower retaining surface 39 faces the slot flange retaining surfaces 37 (see FIG. 9). The slot lower retaining surface 39 and the slot flange retaining surfaces 37 converge and are sloped toward each other. That is, the depth (see arrows D1 and D2 on FIG. 9) of the slot 28 between the surfaces 37, 39 decreases in a direction from the interior perimeter 27 or first slot end 35 to the second slot end 34 (see arrow B on FIG. 9). Note that the slot 28 generally has a tapered wedge shape such that the cross-section of the slot 28 at the open first slot end 35 is larger than the cross-section of the slot 28 at the second slot end 34 (See FIG. 8). Note that the first slot end 35 is opposite the second slot end 34.
Referring now to FIGS. 10-15, an example vane 50 of the present disclosure is depicted. The vane 50 generally includes a vane portion 51 for accelerating the media as described above. The vane portion 51 includes an upper first flange 52 and a lower second flange 53. A generally wedged-shaped main vane body 57 between the flanges 52, 53 and opposing vane side surfaces 54 extends between the flanges 52, 53. During operation of the assembly 19, the media contacts one vane side surface 54 and the rotation of assembly 19 including vane 50 and wheel 20 about axis 22 cause the media to be propelled along the vane side surface 54 in an axial direction away from the center axis 22 of the assembly (See FIG. 1; see also arrow A on FIG. 9). The vane 50 has a free, first vane end 55, and when the vane 50 is coupled to the wheel 20 (FIG. 3) the first vane end 55 radially extends away from the exterior perimeter 26 (see FIG. 3). The vane 50 has an opposite second vane end 56, and when the vane 50 is coupled to the wheel (FIG. 3) the second vane end 56 is positioned near the interior perimeter 27 when the vane 50 (see FIG. 3). In one example, the width and/or cross-section of the body 57 tapers a direction from the first vane end 55 to the second vane end 56 (see arrow E on FIG. 10) such that the width of the body 57 between the opposing vane side surfaces 54 is greater near the first vane end 55 than the second vane end 56 (see FIG. 14 which depicts the width W3 at the first vane end 55 and FIG. 15 which depicts the width W4 at the second vane end 56). Note that in other examples, the cross-section of the body 57 is constant along the length of the body 57 between the vane ends 55, 56. Note that in some examples, the body 57 includes a tapering, rounded cross-section that begins above the attachment portion 60 (see below) and tapers toward the second vane end 56. In this example, the cross-section of the body 57 is larger near the first vane end 56 thereby increasing the strength of the body 57 albeit being more expensive due to added materials relative to the example depicted in FIGS. 10-15.
The lower flange 53 is integrally coupled to an attachment portion 60 of the vane 50. The attachment portion 60 is for attaching the vane 50 to the wheel 20 by inserting and sliding the attachment portion 60 into the slot 28 (see FIG. 3) in a radial direction away from the axis 22 (see arrow A on FIG. 3). The attachment portion 60 has a first end 61 (described further herein) positioned closer to the first vane end 55 than the second vane end 56. When the vane 50 is attached to the wheel 20 (see FIG. 3), the first end 61 of vane attachment portion 60 is adjacent to the second slot end 34 of the slot and the attachment end 62 is near the first slot end 35 (see FIG. 4).
The attachment portion 60 also includes opposing lower first vane side retaining surfaces 63, vane end retaining surfaces 64A-B, a vane base retaining surface 65, a pair of vane shoulder retaining surfaces 66, and opposing vane upper side retaining surfaces 67 (See FIG. 12). Note that curved vane transition surfaces 68 with rounded edges are between the retaining surfaces 63, 64, 65, 66. In other examples, in other examples, angular edges are between the retaining surfaces 63, 64, 65, 66.
The first vane side retaining surfaces 63 have a first width W5 (FIG. 13) near the second end 62 and a second width W6 near the first end 61. The first width W5 is greater than the second width W6, and the width of the first vane side retaining surface 63 tapers in a direction from the second end 62 to the first end 61 (see arrow C on FIG. 13). Further, the thickness of attachment portion 60 tapers in a direction from the second end 62 to the first end 61 such that the attachment portion 60 is generally shaped as a wedge or reducing rectangle (see first and second thickness T1 and T2 on FIG. 13). The size and shape of the first vane side retaining surface 63 corresponds to the size and shape of the slot side retaining surface 38 (FIG. 4) such that when the attachment portion 60 is received in the slot 28 (see FIG. 3) the first vane side retaining surface 63 abuts the slot side retaining surface 38.
The vane end retaining surfaces 64A-B are at the first end 61 and extend between the vane side retaining surfaces 63 (see FIGS. 9 and 12). A first vane end retaining surface 64A is curved and generally corresponds to the shape of the first section 44A of the slot end retaining surface 40 of the wheel 20 (see also FIG. 3). In one example, the first vane end retaining surface 64A has a convex shape. A second vane end retaining surface 64B is curved toward the first vane end 55 and adjacent to the first vane end retaining surface 64A. The second vane end retaining surface 64B abuts and transitions to the first vane end retaining surface 64A without an angular or rounded edge therebetween (e.g., smooth transition between the surfaces 64A, 64B). In certain examples, the shape of the second vane end retaining surface 64B corresponds to the shape of the second section 44B of the slot end retaining surface 40 of the wheel (see also FIG. 3). Accordingly, when the attachment portion 60 is received in the slot 28 (see FIG. 3), the vane end retaining surfaces 64A-B nest next to and/or abut the first and second sections 44A, 44B of the first vane end retaining surface 64A (see FIG. 4). Referring to FIG. 12, a first axis 71 extends along the bottom surface of the lower flange 53 and a second axis 72 extends perpendicular to the first axis 71. The first axis 71 extends tangential to a transition point between the bottom surface of the lower flange 53 and the upper edge of the second vane end retaining surface 64B. In certain examples, the first vane end retaining surface 64A has a constant radius extending from an axis 73 (See FIG. 13). In one non-limiting example, the radius of the first vane end retaining surface 64A is 0.633 inches. In one non-limiting example, the radius of the first vane end retaining surface 64A is within a range 0.75-0.50 inches. The opposing sides of the first vane end retaining surface 64A extend in a direction from the first vane end 55 toward the second vane end 56 (see arrows J).
The second vane end retaining surface 64B has a generally concave shape with the opposing ends 90 that extend in a direction toward the second vane end 56 (see arrow K on FIG. 13). In certain examples, the second vane end retaining surface 64B is at least partially concave. In certain examples, the second vane end retaining surface 64B is concave relative to a third axis 73 that is parallel and offset from the second axis 72 (See FIG. 13) and also convex relative to a second line axis 74 (see FIG. 13). In certain examples, a first centerline 91 (e.g., minor centerline that extends between upper and lower edges of the surface 64B) of the second vane end retaining surface 64B extends along a radius that extends from the third axis 73 or first line axis 75 and a second centerline 92 (e.g., major centerline that extends along the surface 64B between the ends 90) that extends along a radius that extends from the second line axis 74. In certain examples, the first centerline 91 is perpendicular to the second centerline 92 at the intersection thereof. In certain examples, the cross-section of the second vane end retaining surface 64B along the second centerline 92 is concave. In certain examples, the second vane end retaining surface 64B has negative curvature, e.g., the surface at a given point curves away from the tangent plane in two different directions. In certain examples, the second vane end retaining surface 64B is shaped as a portion of an internal surface of a hollow torus that lies opposite to a portion of the exterior surface that faces the center and center void of the torus. In certain examples, the second vane end retaining surface 64B has a generally convex shape that is bowed such that the opposing ends 90 are oriented and extend toward the second vane end 56. In certain examples, the second vane end retaining surface 64B is generally concave shape with the opposing ends 90 that extend in a direction toward the second vane end 56 (see arrow K on FIG. 13). In certain examples, the opposing ends 90 of the second vane end retaining surface 64B flare in a direction toward the second vane end 56. In one example, the second vane retaining surface 64B has a radius of 0.155 inches. In another example, the second vane retaining surface 64B has a radius in the range of 0.100-0.300 inches. The shape of the second vane end retaining surface 64B advantageously allows for various manufacturing methods of the wheel 20 including the ability to machine with the wheel 20 without expensive custom tooling or use of a casting process.
The present inventors have discovered that providing the second vane end retaining surface 64B as described above has many benefits over conventional vanes and advantageously provides a sufficient area for spreading the loads and stresses acting on the second vane end retaining surface 64B caused by contact of the second vane end retaining surface 64B with the wheel 20. Furthermore, the second vane end retaining surface 64B acts to spread and distribute the loads and stresses to other adjacent surfaces such as the first vane end retaining surface 64A and/or outer surface of the lower flange 53. During operation of the assembly 19, the second vane end retaining surface, the first vane end retaining surface 64A, and/or outer surface of the lower flange are often the most highly loaded surfaces and components of the vane 50. Note that FIG. 16 shows the theoretical load in conventional art vanes and is the location of most in-use failures.
The vane base retaining surface 65 is generally planar (see FIG. 12), and the vane base retaining surface 65 is sized and shaped to correspond with the size and shape of the slot lower retaining surface 39 (see FIG. 5). Note that in certain examples, the flange 52, 53 and the surfaces 63, 65 each have two degrees of draft angle in each direction for release of the casting pattern from the casting mold. As such, when the attachment portion 60 is received in the slot 28 (see FIG. 3) the vane base retaining surface 65 abuts the slot lower retaining surfaces 39 (see FIG. 7).
The vane shoulder retaining surfaces 66 are positioned on opposing sides of the attachment portion 60 such that the lower flange 53 is between the vane shoulder retaining surfaces 66 and the first flange 52 (See FIG. 10). The size and shape of the vane shoulder retaining surfaces 66 correspond to the size and shape of the slot flange retaining surface 37 (see FIG. 7-8). As such, when the attachment portion 60 is received in the slot 28 (see FIG. 3) the vane shoulder retaining surfaces 66 abut the slot flange retaining surfaces 37 (see FIGS. 7-8).
The vane upper side retaining surfaces 67 are spaced apart from the first vane side retaining surfaces 63 (see FIG. 13). The vane upper side retaining surface 67 has a first width W7 near the second end 62 and a second width W8 near the first end 61. The first width W7 is less than the second width W8, and the width of the vane upper side retaining surface 67 tapers in a direction from the second end 62 to the first end 61 (see arrow D on FIG. 13). The size and shape of the vane upper side retaining surface 67 corresponds to the size and shape of the side flange surfaces 30 (see FIG. 8-9).
When the vane 50 is in the slot 28 (see FIG. 3), the vane shoulder retaining surfaces 66 engage with the slot flange retaining surfaces 37 and the vane upper side retaining surfaces 67 engage with the side flange surfaces 30. Rotation of the wheel 20 (see FIG. 2) and flow of abrasive across surface 54 (see FIG. 10) causes these surfaces to experience forces (e.g., twisting forces, compression forces) as the wheel 20 is rotated and the vane 50 is rotated with the wheel 20. However, when the wheel 20 stops rotating and the vane 50 is removed from slot 28, the increasing the width of the vane shoulder retaining surfaces 66 in a direction from the first end 61 to the second end 62 (e.g., see arrow D on FIG. 13) and the increasing width of the first vane side retaining surfaces 63 in a direction from the first end 61 to the second end 62 (e.g., see arrow D on FIG. 13) and/or the tapered shaped of the attachment portion 60 (as noted above) advantageously permits the easy release of the vane 50 from the slot 28 (“shot lock” releases immediately after initial movement during vane removal); frictional forces between the vane 50 and the wheel 20 are easily overcome. Also note that lower flange 53 abuts the upper slot surface 45 thereby providing additional strength to the vane portion 51.
In certain examples, a blasting assembly includes a wheel that is rotatable about a first axis. The wheel defines a hole centered about the first axis and at least one radially extending slot that has an open first slot end that faces the hole and a second slot end that is opposite the first slot end and is at least partially closed. A vane is configured to be received into each radially extending slot such that each vane is retained in a radially extending slot as the wheel is rotated and configured to propel media. The vane includes a body radially extending between a first vane end and a second vane end, and the body extending between a first flange and a second flange, and having opposing vane side surfaces. An attachment portion integral with the second flange, and the attachment portion configured to be received into the slot. The attachment portion has a first vane end retaining surface and a second vane end retaining surface that abut the second slot end. The first vane end retaining surface and the second vane end retaining surface are adjacent to each other, the first vane end retaining surface is convex, and the second vane end retaining surface is concave.
Optionally, the second vane end retaining surface abuts the first vane end retaining surface without an edge therebetween. Optionally, the second vane end retaining surface of the attachment portion has opposing ends that extend in a direction toward the second vane end. Optionally, the second vane end retaining surface has a radially extending first centerline that extends along a radius extending from a first line axis and a second centerline that extends along a radius extending from a second line axis. Optionally, the second vane end retaining surface has negative curvature. Optionally, the second slot end has a slot end retaining surface having a first section that corresponds to the first vane end retaining surface and a second section that corresponds to the second vane end retaining surface. Optionally, depth of the slot tapers in a direction from the first slot end to the second slot end. Optionally, the wheel has a slot flange having a thickness that tapers in a direction from the second slot end to the first slot end. Optionally, the attachment portion has a first end and an opposite second end, and thickness of the attachment portion tapers in a direction from the second end toward the first end. Optionally, the attachment portion has a vane base retaining surface and a pair of vane shoulder retaining surfaces that converge toward each other in a direction from the second end of the attachment portion toward the first end of the attachment portion, and one of the pair of vane shoulder retaining surfaces is on opposite sides of a vane portion of the vane. Optionally, the attachment portion has a vane side retaining surface with width that tapers in a direction from the second end of the attachment portion toward the first end of the attachment portion.
In certain examples, a vane for insertion into a slot of a wheel of a blasting assembly such that the vane propels media as the wheel is rotated includes a body radially extending between a first vane end and a second vane end, between a first flange and a second flange, and having opposing vane side surfaces. An attachment portion integral with the second flange, the attachment portion configured to be received into the slot, and the attachment portion has a first vane end retaining surface and a second vane end retaining surface that are configured to abut the wheel. The first vane end retaining surface and the second vane end retaining surface are adjacent to each other, the first vane end retaining surface is convex, and the second vane end retaining surface is concave.
Optionally, the second vane end retaining surface abuts the first vane end retaining surface without an edge therebetween. Optionally, the second vane end retaining surface has opposing ends that extend in a direction toward the second vane end. Optionally, the second vane end retaining surface has a radially extending first centerline that extends along a radius extending from a first line axis and a second centerline that extends along a radius extending from a second line axis. Optionally, the second vane end retaining surface has negative curvature. Optionally, the attachment portion has a first end and an opposite second end, and the attachment portion tapers in a direction from the second end toward the first end. Optionally, the attachment portion has a vane base retaining surface and a pair of vane shoulder retaining surfaces that converge toward each other in a direction from the second end of the attachment portion toward the first end of the attachment portion, and one of the pair of vane shoulder retaining surfaces is on opposite sides of a vane portion of the vane. Optionally, the attachment portion has a vane side retaining surface that tapers in a direction from the second end of the attachment portion toward the first end of the attachment portion. Optionally, the vane is configured to be held in the slot through centrifugal force as the wheel is rotated.
In the present description, certain terms have been used for brevity, clarity, and understanding. No unnecessary limitations are to be inferred therefrom beyond the requirement of the prior art because such terms are used for descriptive purposes and are intended to be broadly construed. The different apparatuses, systems, and method steps described herein may be used alone or in combination with other apparatuses, systems, and methods. It is to be expected that various equivalents, alternatives and modifications are possible within the scope of the appended claims.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
Patent Application
20230278168
