Bend limiting strain relief boot

• US 5,781,681 A
• Filed: 11/14/1996
• Issued: 07/14/1998
• Est. Priority Date: 11/22/1995
• Status: Expired due to Term

• Current Assignee: Tyco Electronics Services GmbH (TE Connectivity Ltd. (United Kingdom))
• Original Assignee: The Whitaker Corporation (Meggitt PLC)
• Inventors: Manning, Randy Marshall
• Primary Examiner(s): Bovernick, Rodney B.
• Assistant Examiner(s): Sanghavi, Hemang
• Application Number:
  US08/748,761
• Time in Patent Office: 607 Days
• Field of Search: 385/86, 385/87, 385/136, 385/62, 385/76, 385/81
• US Class Current: 385/86
• CPC Class Codes: G02B 6/38875 Protection from bending or twisting
• CPC Class Codes: G02B 6/3888 Protection from over-extension or over-compression
• CPC Class Codes: G02B 6/4478 Bending relief means
• CPC Class Codes: H01R 13/562 Bending-relieving
• CPC Class Codes: H02G 15/007 Devices for relieving mechanical stress

Abstract

A bend limiting strain relief boot 1 is disclosed wherein, an outer diameter of the boot 1 varies as a function of a desired minimum bend radius (ρ), a side load applied (F), and the modulus of elasticity (E) of a material from which the boot 1 is made. An outer diameter (d_o (θ)) of the boot varies as a function of its distance from a distal end of the connector following the relationship: ##EQU1## wherein d_i is the inner diameter of the boot, F is the maximum applied load, ρ is the desired minimum radius of curvature, θ is the angle of the applied load relative to said neutral axis, and E is the modulus of elasticity of the selected material.

Claims

1. A bend relief boot (1) comprising a tubular length of polymeric material disposed at a distal end of a connector, the tubular length having a neutral center axis (9) characterized in that:

an outer diameter (d_o (θ

)) of the boot varies as a function of its distance from said distal end of the connector in its fully deflected state following the relationship, ##EQU8## wherein d_i is the inner diameter of the boot, F is the maximum applied load, ρ

is the desired minimum radius of curvature, θ

is the angle of the applied load relative to said neutral axis, and E is the modulus of elasticity of the selected material.

2. A bend relief boot as recited in claim 1 wherein the outer diameter continuously varies over the length of the boot following said relationship.

3. A bend relief boot as recited in claim 1 wherein the outer diameter varies in linear segments as a function of distance from said distal end of the connector over the length of the boot.

4. A bend limiting strain relief boot as recited in claim 1 wherein a length of boot is sufficiently long to extend over a 90 degree transition.

5. A bend limiting strain relief boot having a hollow polygonal cross section and being made of a material having a modulus of elasticity of E and outer and inner dimensions of the boot are selected to control the bend radius according to the relationship:

##EQU9## wherein ρ

is the desired minimum radius of curvature, 1 is the length of said boot, M is the bending moment, and I represents the equation for the moment of inertia relationship;

##EQU10## wherein d_o is the outer diameter of the boot and d_i, is the inner diameter of the boot.