Rotary seal

Patent metadata

Field	Value
Publication number	US-10907688-B2
Application number	US-201916449369-A
Country	US
Kind code	B2
Filing date	Jun 22, 2019
Priority date	Jun 29, 2018
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

A radial gap between an outer circumferential surface of an encoder member joined to an outward flange portion of a slinger and an inner circumferential surface of a seal body includes a first gap portion and a second gap portion closer to an inward flange portion of a core metal than the first gap portion is. The outer circumferential surface that defines the first gap portion is a cylindrical outer circumferential surface, and the radial gap in the first gap portion is substantially constant in an axial direction. The outer circumferential surface that defines the second gap portion is a conical outer circumferential surface reduced in diameter as approaching the inward flange portion of the core metal in the axial direction, and the radial gap in the second gap portion is gradually increased as approaching the inward flange portion of the core metal in the axial direction.

First claim

What is claimed is:

1. A rotary seal comprising:
a slinger attached to an inner diameter-side member;
a core metal attached to an outer diameter-side member; and
a seal body including a seal member joined to the core metal,
wherein
the slinger includes a slinger-cylindrical portion fitted to an outside of the inner diameter-side member and an outward flange portion extending radially outward from an end of the slinger-cylindrical portion in a direction parallel to an axial direction along a rotary shaft of the inner diameter-side member,
the core metal includes a core-metal cylindrical portion fitted to an inside of the outer diameter-side member and an inward flange portion extending radially inward from an end of the core-metal cylindrical portion in a direction parallel to the axial direction,
the seal member includes an axial lip brought into sliding contact with the outward flange portion of the slinger,
a radial gap between an inner circumferential surface of the seal body and an outer circumferential surface of a joined member joined to the outward flange portion of the slinger includes a first gap portion and a second gap portion closer to the inward flange portion of the core metal than the first gap portion is,
the outer circumferential surface that defines the first gap portion is a cylindrical or substantially cylindrical outer circumferential surface,
the radial gap in the first gap portion is substantially constant in a direction parallel to the axial direction,
the outer circumferential surface that defines the second gap portion is a conical or substantially conical outer circumferential surface, which is reduced in diameter as approaching the inward flange portion of the core metal in a direction parallel to the axial direction,
the radial gap in the second gap portion is gradually increased as approaching the inward flange portion of the core metal in a direction parallel to the axial direction,
an inclination angle IA defined by the conical or substantially conical outer circumferential surface with respect to the inner circumferential surface of the seal body is set to 5°≤IA≤30°,
when a length of the rotary seal in the direction parallel to the axial direction is L,
a length L 1 of the first gap in the direction parallel to the axial direction is set to L 1 ≥L×0.2,
a length L 2 of the second gap portion in the direction parallel to the axial direction is set to L 2 ≥L×0.2, and
L 1 +L 2 ≤L×0.8, and

a radial length H of the first gap portion is set to 0.3 mm≤H≤1.0 mm.

2. The rotary seal according to claim 1 , wherein
the joined member includes an encoder member, a synthetic resin member, or a synthetic rubber member.

3. A rotary seal comprising:
a slinger attached to an inner diameter-side member;
a core metal attached to an outer diameter-side member; and
a seal body including a seal member joined to the core metal,
wherein
the slinger includes a slinger-cylindrical portion fitted to an outside of the inner diameter-side member and an outward flange portion extending radially outward from an end of the slinger-cylindrical portion in a direction parallel to an axial direction along a rotary shaft of the inner diameter-side member,
the core metal includes a core-metal cylindrical portion fitted to an inside of the outer diameter-side member and an inward flange portion extending radially inward from an end of the core-metal cylindrical portion in a direction parallel to the axial direction,
the seal member includes an axial lip brought into sliding contact with the outward flange portion of the slinger,
a radial gap between the inner circumferential surface of the seal body and an outer circumferential surface of a bent portion formed by bending the outward flange portion of the slinger includes a first gap portion and a second gap portion closer to the inward flange portion of the core metal than the first gap portion is,
the outer circumferential surface that defines the first gap portion is a cylindrical or substantially cylindrical outer circumferential surface,
the radial gap in the first gap portion is substantially constant in a direction parallel to the axial direction,
the outer circumferential surface that defines the second gap portion is a conical or substantially conical outer circumferential surface, which is reduced in diameter as approaching the inward flange portion of the core metal in a direction parallel to the axial direction,
the radial gap in the second gap portion is gradually increased as approaching the inward flange portion of the core metal in a direction parallel to the axial direction,
an inclination angle IA defined by the conical or substantially conical outer circumferential surface with respect to the inner circumferential surface of the seal body is set to 5°≤IA≤30°,
when a length of the rotary seal in the direction parallel to the axial direction is L,
a length L 1 of the first apportion in the direction parallel to the axial direction is set to L 1 ≥L×0.2,
a length L 2 of the second gap portion in the direction parallel to the axial direction is set to L 2 ≥L×0.2, and
L 1 +L 2 ≤L×0.8, and

a radial length H of the first gap portion is set to 0.3 mm≤H≤1.0 mm.

Assignees

• Nakanishi Metal Works Co

Inventors

• Kamiji Michiyuki
• Sato Takahiko
• Akashi Shinichi
• Iizawa Yusuke

Classifications

• F16J15/3252

  with rigid casings or supports · CPC title

• F16C33/7876

  with sealing lips · CPC title

• F16C33/7873

  with a single sealing ring of generally L-shaped cross-section · CPC title

• F16J15/3232

  having two or more lips · CPC title

• F16C33/7883

  mounted to the inner race and of generally L-shape, the two sealing rings defining a sealing with box-shaped cross-section · CPC title