Method for producing a threaded nut of a threaded drive, in particular a ball screw nut of a ball screw drive

Patent metadata

Field	Value
Publication number	US-12253144-B2
Application number	US-202017629797-A
Country	US
Kind code	B2
Filing date	Jun 25, 2020
Priority date	Aug 1, 2019
Publication date	Mar 18, 2025
Grant date	Mar 18, 2025

Abstract

The disclosure relates to a method for producing a threaded nut of a threaded drive. In a forming process, a sleeve is produced from a steel sheet which is suitable for case-hardening. A flange is integrally formed on the sleeve for welding to a machine part. A welding surface of the flange has a diffusion-inhibiting layer which inhibits the penetration of carbon into the welding surface. The sleeve is case-hardened, and the welding surface is then exposed by removing the diffusion-inhibiting layer. The sleeve can be bonded to a machine part on the exposed welding surface of the sleeve.

First claim

The invention claimed is:

1. A method for producing a threaded nut of a threaded drive, the method comprising:
forming a sleeve from a steel sheet, the steel sheet configured for case-hardening,
forming a flange integrally with the sleeve, the flange having a welding surface configured for welding to a machine part,
forming a rolling profile on an inner circumference of the sleeve, the rolling profile: i) configured for rolling contact with rolling elements; and, ii) extending helically around a longitudinal axis of the sleeve,
applying a diffusion-inhibiting layer to at least a side of the flange facing the machine part, the diffusion-inhibiting layer configured to inhibit penetration of carbon into the welding surface, and
case-hardening the sleeve.

2. The method according to claim 1 , further comprising:
removing at least a portion of the diffusion-inhibiting layer after the case-hardening so as to expose the welding surface.

3. The method according to claim 1 , wherein the applying includes applying the diffusion-inhibiting layer to an outer circumference of the sleeve before the case-hardening.

4. The method according claim 1 , wherein the applying includes only applying the diffusion-inhibiting layer to the flange after the sleeve has been formed.

5. The method according to claim 1 , wherein the diffusion-inhibiting layer is formed by copper.

6. The method according to claim 1 , wherein the diffusion-inhibiting layer is electroplated on the side facing the machine part.

7. The method according to claim 2 , further comprising:
welding the welding surface to the machine part after the removing.

8. The method according to claim 3 , further comprising:
removing a portion of the diffusion-inhibiting layer in a region of the welding surface after the case-hardening.

9. The method according to claim 8 , further comprising:
welding the welding surface to the machine part after the removing.

10. The method according to claim 4 , further comprising:
removing the diffusion-inhibiting layer in a region of the welding surface after the case-hardening.

11. The method according to claim 10 , further comprising:
welding the welding surface to the machine part after the removing.

12. A method for producing a threaded nut of a threaded drive, the method comprising:
providing a steel sheet having a diffusion-inhibiting layer, the diffusion-inhibiting layer configured to inhibit penetration of carbon during a case-hardening process of the steel sheet,
forming a sleeve from the steel sheet, the diffusion-inhibiting layer arranged on an outer surface of the sleeve,
forming a flange integrally with the sleeve, the flange having a welding surface covered by a portion of the diffusion-inhibiting layer, the welding surface configured for welding to a machine part,
forming a rolling profile on an inner circumference of the sleeve, the rolling profile: i) configured for rolling contact with rolling elements, and ii) extending helically around a longitudinal axis of the sleeve, and
case-hardening the sleeve.

13. The method according to claim 12 , further comprising:
removing the portion of the diffusion-inhibiting layer covering the welding surface after the case-hardening.

14. The method according to claim 12 , wherein the diffusion-inhibiting layer is formed by electroplating the steel sheet.

15. The method according to claim 12 , wherein the diffusion-inhibiting layer is formed by copper.

Assignees

• Schaeffler Technologies Ag

Inventors

• Kreutzer Mario
• Eckert Dieter
• Heinz Paul
• Baier Richard

Classifications

• B21D53/24

  nuts or like thread-engaging members · CPC title

• F16H2025/249

  Materials or coatings for screws or nuts · CPC title

• F16H2025/2481

  Special features for facilitating the manufacturing of spindles, nuts, or sleeves of screw devices · CPC title

• F16H25/24

  Elements essential to such mechanisms, e.g. screws, nuts (F16H25/22 takes precedence) · CPC title

• F16H25/2204 Primary

  with balls · CPC title