Torsional vibration damper spoke design

Patent metadata

Field	Value
Publication number	US-2016290472-A1
Application number	US-201615084636-A
Country	US
Kind code	A1
Filing date	Mar 30, 2016
Priority date	Mar 30, 2015
Publication date	Oct 6, 2016
Grant date	—

Abstract

Torsional vibration dampers (TVDs) having a plurality of spokes designed to withstand both torsional and bending forces and vibrations are disclosed. The spokes, which connect a central member to a peripheral rim, include a first end coupled to an outer radial surface of the central member; a second end coupled to an inner radial surface of the rim; and four concave surfaces extending between the first end and the second end. The concave surfaces may be concave from the first end to the second end and may also be concave laterally from front to back or side to side. A TVD having a hub with spokes having one or more concave surfaces is also disclosed herein. A method of designing the spokes for the hub is also disclosed.

First claim

What is claimed is:

1 . A torsional vibration damper comprising:
a hub; and an inertia member concentric about the hub with an elastomeric member operatively positioned therebetween; wherein the hub comprises a plurality of spokes extending from an outer radial surface of a central member to an inner radial surface of a peripheral rim, each of the plurality of spokes comprising:
a first end coupled to the outer radial surface of the central member;
a second end coupled to the inner radial surface of the peripheral rim;
a first concave surface extending between the first end and the second end and facing an axial direction;
a second concave surface extending between the first end and the second end and facing opposite the first concave surface;
a third concave surface extending between the first end and the second end and between the first concave surface and the second concave surface; and
a fourth concave surface extending between the first end and the second end and between the first concave surface and the second concave surface, wherein the fourth concave surface faces generally opposite the third concave surface.

2 . The torsional vibration damper of claim 1 , wherein, for each of the plurality of spokes, the first concave surface and the second concave surface are concave extending from the first end to the second end.

3 . The torsional vibration damper of claim 2 , wherein, for each of the plurality of spokes, the first concave surface and the second concave surface are additionally concave extending from the third concave surface to the fourth concave surface.

4 . The torsional vibration damper of claim 1 , wherein, for each of the plurality of spokes, the third concave surface and the fourth concave surface are concave extending from the first end to the second end.

5 . The torsional vibration damper of claim 4 , wherein, for each of the plurality of spokes, the third concave surface and the fourth concave surface are generally flat extending from the first concave surface to the second concave surface.

6 . The torsional vibration damper of claim 1 , wherein the third concave surface faces generally perpendicular to the axial direction.

7 . The torsional vibration damper of claim 2 , wherein, for each of the plurality of spokes, at least one concavity of at least one of the first concave surface, second concave surface, third concave surface, and fourth concave surface is defined by an arc of a circle.

8 . The torsional vibration damper of claim 1 , wherein, for each of the plurality of spokes, the width of the second end is smaller than the first end.

9 . The torsional vibration damper of claim 1 , wherein, for each of the plurality of spokes, the first end has a shape that conforms to the outer radial surface of the central member, and the second end has a shape that conforms to the inner radial surface of the peripheral rim.

10 . A front end accessory drive system comprising the torsional vibration damper of claim 1 mounted to a crankshaft for rotation therewith.

11 . A method of designing a spoke for a torsion vibration damper, the method comprising:
drawing a central member offset outer diameter inward from an outer diameter of a central member by a selected first offset; drawing a peripheral rim offset inner diameter outward from an inner diameter of a peripheral rim; drawing a first line radially outward from a center axis of the torsional vibration damper to at least the peripheral rim offset inner diameter at a position representing a midsagittal plane of a first spoke; drawing a second line radially outward from the center axis of the torsional vibration damper to at least the peripheral rim offset diameter at a position representing a midsagittal plane of a neighboring second spoke; drawing a third line parallel to the first line and laterally offset therefrom by a selected second offset; drawing a fourth line parallel to the second line and laterally offset therefrom, but toward the third line, by the second offset; drawing a first arc tangent to the third line, the fourth line, and the central member offset outer diameter; drawing a second arc as a mirror image of the first arc relative to the first line, thereby defining opposing sides of a starting spoke geometry; removing lines and diameter circles except those defining the starting spoke geometry; reproducing the starting spoke geometry a plurality of times and disposing at least two thereof above and at least two thereof below a centrally positioned spoke geometry thereof, wherein the outermost spoke geometry above and below the centrally positioned spoke geometry is closer to its neighboring spoke geometry than its neighbor is to the central starting spoke geometry; drawing eight arcs using each set of adjacent corners of each of the outermost spoke geometries, wherein the arcs extend between the adjacent corners and pass through a midpoint between the same adjacent corners of its neighboring spoke geometry; drawing four line segments, parallel to the axis, from each of the corners of one of the outermost spoke geometries to the same corner of the other outermost spoke geometry; and retaining only the eight arcs and four line segments thereby defining the three dimensional shape of the first spoke.

12 . A method of designing a torsional vibration damper, the method comprising:
performing the steps of claim 11 ; forming surfaces of the three dimensional shape of the first spoke; reproducing the three dimensional shape of the first spoke to define a plurality thereof equivalent to a preselected number of spokes; arranging the plurality of spokes about a central axis of the torsional vibration damper as a polar array with each of the first ends toward the central axis; drawing the central member against the first end of each of the plurality of spokes; and drawing the peripheral rim against the second end of each of the plurality of spokes.

13 . The method of claim 12 , wherein drawing the central member comprises unhiding the central member, and drawing the peripheral rim comprises unhiding the peripheral rim.

14 . The method of claim 12 , further comprising extruding the washer face of the central member.

15 . The method of claim 12 , further comprising creating a circle on one axial face of the central member to define a seal nose.

16 . The method of claim 15 , further comprising elongating, axially, the seal nose.

17 . The method of claim 12 , further comprising adding chamfers and fillets.

Assignees

• Manzoor Suhale
• Dayco Ip Holdings Llc

Inventors

• Manzoor Suhale

Classifications

• F16H55/36

  Pulleys (with features essential for adjustment F16H55/52) · CPC title

• F16H2055/366

  with means providing resilience or vibration damping · CPC title

• F16H55/40 Primary

  with spokes (F16H55/48 takes precedence) · CPC title