Manufacturing method for slinger used in rotary seal, and rotary seal

Patent metadata

Field	Value
Publication number	US-11421741-B2
Application number	US-202016773290-A
Country	US
Kind code	B2
Filing date	Jan 27, 2020
Priority date	Jan 29, 2019
Publication date	Aug 23, 2022
Grant date	Aug 23, 2022

Abstract

A manufacturing method of a slinger, includes steps of: molding an annular blank material from a dull-finished steel sheet material through sheet metal press working or the like; and burring the blank material to mold a slinger. The values of the arithmetical mean roughness Ra of faces, of a burring mold, which individually come into contact with first and second slide-contact surfaces of the slinger, are set to 0.03 μm≤Ra≤0.07 μm. A ratio of pressure application force for holding the blank material between the faces to the 0.2% proof stress of the dull-finished material, is set to 1.0 or more and 1.53 or less. A clearance for the burring mold is set to T×(0.9 to 0.7) where “T” represents the sheet thickness of the blank material.

First claim

What is claimed is:

1. A manufacturing method of a slinger to be used in a rotary seal that includes the slinger, a core metal, and a seal member,
the slinger including a cylindrical sleeve and a flange extending outward in a radial direction from one end of the sleeve in an axial direction,
the core metal including a core metal cylinder having a cylindrical shape, and a core metal flange extending inward in the radial direction from one end of the core metal cylinder in the axial direction,
the seal member including a base portion joined to the core metal, and a seal lip portion extending from the base portion,
the seal lip portion including an axial lip in slidable contact with a first slide-contact surface that is an inner surface of the flange of the slinger, and a radial lip in slidable contact with a second slide-contact surface that is an outer circumferential surface of the sleeve of the slinger,
the manufacturing method comprising:
molding an annular blank material from a dull-finished steel sheet material through sheet metal press working, laser cutting machining, or wire cut electric discharge machining; and
burring the annular blank material, so as to mold the slinger, wherein

the burring is performed using a mold having faces each of which has an arithmetical mean roughness Ra set to 0.03 μm≤Ra≤0.07 μm, the faces individually coming into contact with the first slide-contact surface and the second slide-contact surface,
a ratio of pressure application force for holding the annular blank material between the faces to a 0.2% proof stress of the dull-finished material, is set to 1.0 or more and 1.53 or less,
a clearance for the mold used for the burring is set to T×(0.9 to 0.7) where “T” represents a sheet thickness of the annular blank material, and,
with these conditions, an arithmetical mean roughness Ra of each of the first slide-contact surface and the second slide-contact surface of the slinger falls within a predetermined range of 0.25 μm≤Ra≤0.5 μm.

2. A manufacturing method of a slinger to be used in a rotary seal that includes the slinger, a core metal, and a seal member,
the slinger including a cylindrical sleeve and a flange extending outward in a radial direction from one end of the sleeve in an axial direction,
the core metal including a core metal cylinder having a cylindrical shape, and a core metal flange extending inward in the radial direction from one end of the core metal cylinder in the axial direction,
the seal member including a base portion joined to the core metal, and a seal lip portion extending from the base portion,
the seal lip portion including an axial lip in slidable contact with a first slide-contact surface which is an inner surface of the flange of the slinger, and a radial lip in slidable contact with a second slide-contact surface which is an outer circumferential surface of the sleeve of the slinger,
the manufacturing method comprising:
molding an annular blank material from a dull-finished steel sheet material through sheet metal press working, laser cutting machining, or wire cut electric discharge machining;
burring the annular blank material, so as to mold the slinger; and
pressing a mold against the first slide-contact surface of the molded slinger, wherein

the burring is performed using a mold having a face that has an arithmetical mean roughness Ra set to 0.03 μm≤Ra≤0.07 μm, the face coming into contact with the second slide-contact surface,
a clearance for the mold used for the burring is set to T×(0.9 to 0.7) where “T” represents a sheet thickness of the annular blank material,
the pressing is performed using a mold having a face with an arithmetical mean roughness Ra set to 0.03 μm≤Ra≤0.07 μm, the face coming into contact with the first slide-contact surface,
a ratio of pressing force for pressing the mold in the pressing to a 0.2% proof stress of the dull-finished material is set to 1.0 or more and 1.53 or less, and,
with these conditions, an arithmetical mean roughness Ra of each of the first slide-contact surface and the second slide-contact surface of the slinger falls within a predetermined range of 0.25 μm≤Ra≤0.5 μm.

Assignees

• Nakanishi Metal Works Co

Inventors

• Shimada Wataru
• Akashi Shinichi
• Iizawa Yusuke

Classifications

• B60B27/0073

  characterised by sealing means · CPC title

• F16C33/7823

  of sealing lips · CPC title

• F16C2220/40

  by deformation without removing material · CPC title

• F16C2220/02

  by casting · CPC title

• F16J15/3252

  with rigid casings or supports · CPC title