BACKGROUND
The disclosure relates to a wing pulley having an integral support and build fixture for supporting and locating the wings and the spacers of the wing pulley.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A shows an exploded perspective view of a wing pulley as described herein;
FIG. 1B shows an exploded perspective view of an alternate embodiment of the wing pulley of FIG. 1A;
FIG. 2 shows a perspective view of the wing pulley of FIG. 1A with a wing removed and adjacent spacers removed to show the relative construction of the wing pulley;
FIG. 3 shows a front elevational view of a hub of the wing pulley of FIG. 1A;
FIG. 4 shows a side view of the hub of FIG. 3;
FIG. 5 shows a front elevational view of a support of the wing pulley of FIG. 1A;
FIG. 6 shows a side view of the support of FIG. 5; and
FIG. 7 is view of the pulley of FIG. 1A from an axial end with three wings positioned in slots of the support and a spacer positioned between adjacent wings with a portion of the hub shown in section to illustrate the cooperative relationship of the aforementioned elements.
DETAILED DESCRIPTION
Referring to FIGS. 1A and 1B, the wing pulley 20 comprises a plurality of wings 22 extending radially outward from an axis of rotation 24 of the pulley. The axis of rotation 24 of the pulley may coincide with a longitudinal center line or center axis of the pulley. The wings 22 may be equiangularly spaced about the center axis of the pulley. Although the drawings show an embodiment of the pulley with 10 wings, other configurations may be used. The wings may extend in length to define a longitudinal length L (FIG. 1A,1B) of the wing pulley. Each of the wings has a width W (FIG. 1A,1B) that as described below in part defines a diameter of the wing pulley. One or more wings may have belt engagement surfaces 26 along a distal edge of the wing width W. As shown in the drawings, the belt engagement surfaces 26 are transverse to the wing width distal edge and extend along the length L of the wing. Although the drawings show an embodiment of the pulley with generally flat belt engagement surfaces, other configurations may be used. For instance, the belt engagement surfaces may be rounded or crowned. Belt engagement surface may also be omitted. The wing pulley comprises spacers 28 disposed between the wings 22 of the pulleys. The spacers 28 may be tapered toward longitudinal ends of the pulley.
The pulley may be provided with a hub 30 adjacent to each longitudinal end of the pulley. As shown in the drawings, the longitudinal length of the wings 22 may be longer than the axial distance between the hubs such that a portion of the length L of the wing extends axially beyond the hubs 30. As shown in FIG. 1A, the hubs 30 have an outer diameter 32 and a locating diameter 34 which is smaller than the outer diameter, and the locating diameter 34 supports each of the wings 22 on a proximal width edge of the wing. The locating diameter 34 may also support the spacers 28. FIG. 1B shows an alternate embodiment of the wing pulley of FIG. 1A where the hubs 30 have an outer diameter 32 that supports the wings 22, and the locator diameter (i.e., “34” of FIG. 1A) has been omitted. In the pulley of FIG. 1B, the wings 22 have their proximal width edges formed with a tab 35 to assist in assembling the pulley as described below in greater detail. The wings and the hubs may also be formed with other features that cooperate with each other to assist in locating the wing on the hub and setting the axial spacing the hub relative to the wing. The hubs 30 may have a center opening 36 to accommodate a shaft of the pulley.
The wing pulley may be provided with an internal support 40 comprising a planar member with an outer periphery 42. As shown in the drawings, the outer periphery 42 comprises flats extending around the periphery to define a polygonal-shape for the support. The support 40 may have a center axis and may have a center hole 44 aligned with center axis to accommodate a shaft (not shown) of the pulley. The center hole may also be omitted. The support 40 may have a plurality of slots 46 extending radially outward in a direction that intersects with a center axis of the support. When assembled to form the pulley, the support axis (and center hole 44) and pulley center axis 24 may be aligned. The slots 46 may have a slot bottom 48. The slot bottoms 48 may be arranged at a distance from the support center hole 44 and spaced from the pulley center axis 24. The support may be provided in a longitudinal center of the pulley as shown in the drawings. With the support in the longitudinal center of the pulley, the spacers may all have the same shape. The support may also be provided in a different position relative to the longitudinal center, and accordingly, the spacers extending toward one hub would be shaped differently from the spacers extending toward the axially opposite hub.
The slots 46 of the support 40 may be formed to accommodate the wings 22 of the pulley. Although not shown in the drawings, the cooperative features of the support and wings may be reversed and the wings may also be formed with slots to accommodate the support, or a combination thereof. The wings and support, for instance, the wing width proximal edge and support slots, may be formed with features that cooperate with each other and locate the support relative to the wings along a longitudinal length of the wing. With the slots 46 of the support 40 arranged to intersect the support center hole 44 (and thus the center axis 24 of the pulley upon assembly), the wings 22 are preferably radially aligned with (i.e., perpendicular to) the center axis of the pulley to provide an optimal force distribution for the wing. The slots 46 may have width dimensions sized in accordance with a thickness of the wings 22 to form a snug fit or press fit between the wings and the slots. The wing width W, together with the relative position of the slot bottoms 48, defines a diameter 50 for the wing pulley (FIG. 7). The outer periphery 42 of the support 40 supports the spacers 28. The outer periphery 42 of the support 40 and the hubs 30 (for instance, the locator diameter 34) may be dimensioned to provide the spacers with a desired taper angle 60 (FIG. 2) relative to the axis of rotation of the pulley. The spacers 28 may be shaped and sized to provide a snug fit between the wings 22 after the wings are fitted in the slots 46 of the support 40 during assembly of the pulley.
The support 40 as described herein provides an internal support and build fixture to facilitate assembly of the wing pulley during manufacture. Thus, the support in effect provides a locator for the wings. Once the wings are installed, the wings and the support, provide a locator for the spacers. In accordance with one exemplary method of manufacturing the pulley, for instance, the support 40 may function as a build fixture to enable manufacturing the pulley with the wings 22 aligned with the center axis 24 of the pulley. An arbor (note shown) may be extended through the opening 36 in each hub 30 and the support center hole 44 along the pulley center axis 24 and used to set the initial axial spacing of the support and hubs along the longitudinal length of the pulley. In the pulley of FIG. 1A, the axial spacing between the hubs may be set by the wing length along the proximal width edge of the wing abutting a shoulder of the hub formed between the outer diameter 32 and the locator diameter 34. In the pulley of FIG. 1B, the axial spacing between the hubs 30 may be set by the wing tabs 35 along the proximal width edge that may be abutted against an inner face of (i.e., behind) the respective hub with the wing proximal width edge seated on the hub outer diameter 32. With the support 40 in position relative to the hubs 30 along the longitudinal length of the pulley, the wings 22 may be seated in their respective slots 46 of the support. The support 40 acts as a fixture to provide the locators for the wings 22. In the pulley of FIG. 1A, longitudinal ends of the wings may be located on the hub locator diameter 34. In the pulley of FIG. 1B, longitudinal ends of the wings may be located on the hub outer diameter 32. In each case, the hub supports each wing. The spacers 28 may then be seated between the wings against the outer periphery 42 of the support 40 and the respective hub 30. For instance, in the pulley of FIG. 1A, the spacers 28 may be supported on the locator diameter 34 of the hub, and in the pulley of FIG. 1B, the spacers 28 may be supported on the outer diameter 34 of the hub. With the spacers 28 fitted to the outer periphery 42 of the support 40 and each respective hub (i.e., the locator diameter 34 (FIG. 1A) or outer diameter 32 (FIG. 1B)), a desired taper angle 60 and a consistent diameter of the spacers is set. The spacers may then be welded to the wings, the support, and the hubs to form an integral pulley. The arbor may then be removed.
The support acts as a stiffener for the wing pulley that prevents wing collapse. The support also provides a build fixture to allow assembly of the wing pulley ensuring that the wings are held perpendicular to the axis of rotation of the pulley, thereby reducing the possibility of wing folding failure. The support also helps locate the spacers at a consistent diameter around the pulley.
In view of the foregoing, it will be seen that several advantages are achieved and attained. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application to thereby enable others skilled in the art to best utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. As various modifications could be made in the constructions and methods herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. The breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.
Patent Application
20130203536
