Gear wheel

Patent metadata

Field	Value
Publication number	US-9291248-B2
Application number	US-201013321342-A
Country	US
Kind code	B2
Filing date	May 20, 2010
Priority date	May 20, 2009
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

The invention relates to a spur gear wheel with a gear body ( 4, 5 ) made from a sintered material, which has a circumference around which teeth ( 6, 7 ) are distributed projecting in the radial direction, and which is delimited by two end faces ( 8, 9, 10, 11 ) in the axial direction. At least one shaped element ( 12 ) in the form of a recess ( 13 ) and/or an elevation ( 14 ) and/or a compacted area is provided on at least one end face ( 8, 9, 10, 11 ) in the region of the teeth ( 6, 7 ) and/or in the radial direction underneath the teeth ( 6, 7 ).

First claim

The invention claimed is:

1. Spur gear wheel with a gear body made from a sintered material, having a circumference around which teeth projecting in the radial direction are distributed, and which is delimited in the axial direction by two end faces, and at least one shaped element in the form of a compacted recess or a compacted elevation is disposed in or on the end faces, the compacted recess being formed in the end face or the compacted elevation projecting above the end face, wherein the at least one shaped element at least approximately imitates the contour of the toothing, wherein in the region of the tooth crests and tooth flanks and in the region of the root line a land is formed on the end face and the end face is visible in these regions in that the at least one shaped element is spaced from an outer circumference of the teeth, the at least one shaped element having a density greater than a density of the outer circumference of the teeth, wherein the at least one shaped element extends in the radial direction at most as far as a region underneath the root line of the teeth consisting of 35% of the maximum diameter of the gear body, and wherein the at least one shaped element covers at least 5% of the surface portion of the teeth on the end face.

2. Spur gear wheel according to claim 1 , wherein the at least one shaped element extends along the external contour of the end face.

3. Spur gear wheel according to claim 1 , wherein the at least one shaped element extends starting at least approximately from the tooth crest circle inwardly in the radial direction.

4. Spur gear wheel according to claim 3 , wherein the at least one shaped element is additionally disposed extending in the axial direction on the tooth crests and/or tooth roots.

5. Spur gear wheel according to claim 1 , wherein the at least one shaped element extends starting at least approximately from the tooth root line inwardly in the radial direction.

6. Spur gear wheel according to claim 1 , wherein a contour of the at least one shaped element is provided with rounded areas at least in the region of a change of direction in the contour line.

7. Spur gear wheel according to claim 1 , wherein the at least one shaped element has an approximately mushroom-shaped cross-section as viewed in the axial direction.

8. Spur gear wheel according to claim 1 , wherein the at least one shaped element has an approximately circular or oval cross-section as viewed in the axial direction.

9. Spur gear wheel according to claim 1 , wherein a transition between the at least one shaped element and the end face is of an angled or rounded design.

10. Spur gear wheel according to claim 1 , wherein the toothing is of a non-uniform design and the tooth geometry and/or tooth strength of at least one of the individual ones of the teeth differs from the tooth geometry and/or tooth strength of the rest of the teeth, and wherein the non-uniformities are disposed in an a-periodic arrangement.

11. Spur gear wheel according to claim 10 , wherein the tooth geometry and/or tooth strength of at least individual teeth varies from the tooth geometry and/or tooth strength of the rest of the teeth.

12. Spur gear wheel according to claim 10 , wherein at least individual ones of the tooth gap depths are bigger or smaller than the tooth gap depths of the rest of the tooth gaps.

13. Spur gear wheel according to claim 10 , wherein a tooth height varies in the range of between 10% and 20% of the tooth height of the tooth with the greatest tooth height.

14. Spur gear wheel according to claim 10 , wherein the tooth gap depths vary in the range of between 5% and 15% of the tooth gap depth of the tooth with the deepest tooth gap.

15. Spur gear wheel according to claim 10 , wherein the tooth width varies in the circumferential direction in the range of between 50% and 100% of the tooth width of the tooth with the greatest tooth width.

16. Spur gear wheel according to claim 10 , wherein the tooth stiffness varies in the range of between 50% and 90% of the tooth stiffness of the tooth with the greatest tooth stiffness.

17. Spur gear wheel according to claim 10 , wherein the teeth are distributed around the circumference with a differing pitch.

18. Spur gear wheel according to claim 10 , wherein the tooth height of at least one tooth varies from the end face in the direction towards the second end face, in particular a tooth crest with a conical aspect is provided in the axial direction.

19. Spur gear wheel according to claim 10 , wherein the tooth width of at least one tooth varies in at least certain regions from the end face in the direction towards the second end face, in particular a tooth flank is provided in the region of the tooth crest with a conical aspect in the axial direction.

20. Spur gear wheel according to claim 10 , wherein the gear body comprises at least three layers in the radial direction, with two peripheral layers and a middle layer, and wherein the middle layer has a lower hardness than the two peripheral layers.

21. Spur gear wheel according to claim 20 , wherein the middle layer is made from a plastic.

22. Spur gear wheel according to claim 20 , wherein the plastic is a thermosetting plastic.

23. Spur gear wheel according to claim 20 , wherein the middle layer has a value for the layer thickness selected from a range with a lower limit of 5% and an upper limit of 700% of the layer thickness of the radially outermost peripheral layer.

24. Spur gear wheel according to claim 20 , wherein the teeth have a hardness of at most 750 HV5.

25. Spur gear wheel according to claim 24 , wherein the teeth have a height whose value is selected from a range with a lower limit of 1% and an upper limit of 50% of the maximum gear diameter.

26. Spur gear wheel according to claim 24 , wherein the teeth have a width whose value is selected from a range with a lower limit of 1% and an upper limit of 50% of the maximum gear diameter.

27. Spur gear wheel according to claim 1 , wherein the at least one shaped element is additionally disposed on at least one of the end faces.

28. Spur gear wheel according to claim 27 , wherein the compacted area has a density of at least 7.2 g/cm 3 , at least in the region of the end face.

Assignees

• Mittermair Mario
• Spitaler Robert
• Mueller Alexander
• Pamminger Helmut
• Miba Sinter Austria Gmbh

Inventors

• Mittermair Mario
• Spitaler Robert
• Mueller Alexander
• Pamminger Helmut

Classifications

• F16H55/17

  Toothed wheels (worm wheels F16H55/22; chain wheels F16H55/30) · CPC title

• F16H2055/086

  Silent gear profiles · CPC title

• F16H55/06 Primary

  Use of materials; Use of treatments of toothed members or worms to affect their intrinsic material properties · CPC title

• Y10T74/19679

  Spur · CPC title

• Y10T74/1987

  Rotary bodies · CPC title