Cardan shaft

Patent metadata

Field	Value
Publication number	US-10619677-B2
Application number	US-201715803108-A
Country	US
Kind code	B2
Filing date	Nov 3, 2017
Priority date	Nov 20, 2014
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

A shaft ( 1 ) is shown comprising a shaft section ( 2 ) having an axis ( 3 ), a tooth geometry ( 4 ) at least at one end of said shaft section, said tooth geometry ( 4 ) having a first end ( 5 ) opposite said shaft section ( 2 ) and a second end ( 6 ) adjacent said shaft section ( 2 ), a number of teeth ( 7 ) distributed in circumferential direction around said axis ( 3 ), a bottom curve ( 9 ) between adjacent teeth ( 7 ), and an outer tooth curve ( 12 ), said bottom curve ( 9 ) having a positive slope from said first end ( 5 ) towards said shaft section ( 2 ) and a negative slope ( 14 ) at said second end ( 6 ). In such a shaft wear should be made as small as possible. To this end said bottom curve ( 9 ) comprises a section having a concave bottom curvature ( 15 ) between said positive slope and said negative slope.

First claim

What is claimed is:

1. A shaft comprising:
a shaft section having an axis;
a tooth geometry disposed at one end of said shaft section, said tooth geometry having a first end distally disposed with respect to said shaft section and a second end proximally disposed with respect to said shaft section; and
a number of teeth in the tooth geometry that are distributed circumferentially around said axis;
wherein the tooth geometry includes a positive slope section, a negative slope section and an axial middle section, the negative slope section being disposed closer to the second end of the tooth geometry than the positive slope section, the axial middle section being disposed between the positive slope section and the negative slope section; and
wherein each of the number of teeth has a thickness in the axial middle section that is reduced with respect to a thickness in the positive slope section and a thickness in the negative slope section.

2. The shaft according to claim 1 , wherein each of the number of teeth includes an outer tooth curve that extends in a direction parallel to said axis and has a positive slope in the positive slope section in a direction from said first end toward said second end and a negative slope in the negative slope section in a direction from said first end toward said second end of said tooth geometry.

3. The shaft according to claim 2 , wherein said outer tooth curve has a largest radius in said axial middle section of said tooth geometry.

4. The shaft according to claim 3 , wherein a distance between adjacent tooth bottoms at said axial middle section is larger than a distance between adjacent tooth bottoms at said positive slope section and said negative slope section of said tooth geometry.

5. The shaft according to claim 2 , wherein a concave bottom curvature is located in the axial middle section of said tooth geometry.

6. The shaft according to claim 5 , wherein said concave bottom curvature is symmetric with respect to said axial middle section of said tooth geometry.

7. The shaft according to claim 2 , wherein a smallest radius of said bottom curve in said axial middle section is larger than a smallest radius of said bottom curve in said positive slope section and said negative slope section of said tooth geometry.

8. The shaft according to claim 1 ,
wherein the tooth geometry includes a bottom curve between adjacent teeth; and
wherein the bottom curve has a positive slope in the positive slope section in a direction from said first end toward said second end, a negative slope in the negative slope section in a direction from said first end toward said second end, and a concave bottom curvature located in the axial middle section of said tooth geometry.

9. The shaft according to claim 8 , wherein a smallest radius of said bottom curve in said axial middle section is larger than a smallest radius of said bottom curve in said positive slope section and said negative slope section of said tooth geometry.

10. The shaft according to claim 9 , wherein said concave bottom curvature is symmetric with respect to said axial middle section of said tooth geometry.

11. The shaft according to claim 8 , wherein said concave bottom curvature is symmetric with respect to said axial middle of said tooth geometry.

12. The shaft according to claim 11 , wherein a distance between adjacent tooth bottoms at said axial middle section is larger than a distance between adjacent tooth bottoms at said positive slope section and said negative slope section of said tooth geometry.

13. The shaft according to claim 8 , wherein said concave bottom curvature is symmetric with respect to said axial middle of said tooth geometry.

14. The shaft according to claim 1 , wherein the shaft section is configured to rotate about said axis.

Assignees

• Danfoss Power Solutions Aps

Inventors

• Soennichsen Vagn

Classifications

• F04C2/104

  having an articulated driving shaft · CPC title

• F16D3/185 Primary

  radial teeth connecting concentric inner and outer coupling parts · CPC title

• F04C2250/00

  Geometry · CPC title

• Y10T403/7035

  Specific angle or shape of rib, key, groove, or shoulder · CPC title

• F04C15/0065

  for eccentric movement · CPC title