Frictional damping strut

• US 6,612,408 B2
• Filed: 09/17/2001
• Issued: 09/02/2003
• Est. Priority Date: 09/17/2001
• Status: Expired due to Term

• Current Assignee: Gates Corporation The
• Original Assignee: Gates Corporation The
• Inventors: Serkh, Alexander, Dec, Andrzej
• Primary Examiner(s): Lavinder, Jack
• Assistant Examiner(s): NGUYEN, XUAN LAN T
• Application Number:
  US09/954,993
• Publication Number:
  US 20030051956A1
• Time in Patent Office: 715 Days
• Field of Search: 188/129, 188/82.8, 188/322.22, 188/134, 188/136, 188/166, 267/196, 267/201, 267/205, 474/133
• US Class Current: 188/129
• CPC Class Codes: F16F 7/08 with friction surfaces rectilinearly movable along each other F16F7/01 takes precedence ; one of the members being a spring F16F13/02
• CPC Class Codes: F16H 2007/0806 Compression coil springs
• CPC Class Codes: F16H 7/0831 of the dry friction type
• CPC Class Codes: F16H 7/1218 of the dry friction type

Abstract

The invention comprises a frictional damping strut. The strut comprises an inner cylinder that slides within an outer casing. A spring biases the inner cylinder away from the outer casing in an axial direction. A first wedge member cooperatively engages a second wedge member. The first wedge member having a frictional engagement with the inner cylinder such that when the inner cylinder is pressed into the outer casing the first wedge member bears upon the second wedge member causing the first wedge member to radially expand, thereby increasing a frictional force between the first wedge member and the inner cylinder. A second spring preloads the first wedge member against the second wedge member. A belt tensioner may incorporate the damping strut to preload a belt and damp belt oscillations.

Claims

1. A strut comprising:

a first member;

a second member coaxially engaged with the first member;

a biasing member engaged between the first member and the second member;

a first wedge member having an axis and slidingly engaged with the second member;

the first wedge member having a frustoconical hole;

a second wedge member connected to the first member and having an axis;

the second wedge member cooperatively engaging the frustoconical hole;

a second biasing member having a first end immovably fixed;

a member attached to the first wedge member and engaging a second end of the second biasing member whereby a movement of the first wedge member is acted upon by the second biasing member acting upon the member;

a rod slidingly extending through a bore in the second wedge member whereby the second biasing member is oppositely placed from the first wedge member relative to the second wedge member;

the second wedge member axially engaged with the first wedge member; and

the first wedge member being expandable in response to a pressure from the second wedge member.

2. The strut as in claim 1, wherein:

the first wedge member further comprises an outer frictional surface having a pleated form; and

the second member having an inner surface having a pleated form for cooperatively engaging the first wedge member outer frictional surface.

3. The strut as in claim 1, wherein:

the first wedge member outer frictional surface and the second member inner surface each having a coefficient of friction.

4. The strut as in claim 1 in combination with:

a base pivotally mountable to a surface;

a pulley having a belt bearing surface, the pulley rotationally mounted to the base; and

a first end of the strut pivotally mounted to the base and a second end of the strut pivotally mountable to a surface.

5. A strut comprising:

a first cylinder and a second cylinder axially engaged;

a first biasing member engaged with the first cylinder and the second cylinder;

a first wedge member frictionally engaged with a surface of the second cylinder, the first wedge movable with respect to the second cylinder;

a second wedge fixed relative to the first cylinder and engageable with the first wedge, the first wedge expandable upon a movement of the first wedge against the second wedge, thereby increasing a frictional force between the first wedge member and the second cylinder;

the first wedge member describing a frustoconical hole and the second wedge member cooperatively engaging the frustoconical hole;

a second biasing member engaged with the first wedge member whereby a first movement of the first wedge member is resisted as a pressure between the first we&

re member and the second wedge member is diminished;

a second movement of the first wedge member is assisted by the second biasing member as a pressure between the first wedge member and the second wedge member is increased;

a member attached to the first wedge member and engaging a second end of the second biasing member whereby a movement of the first wedge member is acted upon by the second biasing member acting upon the member; and

a rod slidingly extending through a bore in the second wedge member whereby the second biasing member is oppositely placed from the first wedge member relative to the second wedge member.

6. The strut as in claim 5, wherein an outer surface of the first wedge member describes a pleated form.

7. The strut as in claim 5 in combination with:

a base pivotally mountable to a surface;

a pulley having a belt bearing surface, the pulley rotationally mounted to the base; and

a first end of the strut pivotally mounted to the base and a second end of the strut pivotally mountable to a surface.