US-20260126098-A1 - SHUTTLING MECHANICAL TENSIONER FOR CONTROL OF CHAIN DRIVES WITH ALTERNATING TIGHT AND SLACK STRANDS

US20260126098A1US 20260126098 A1US20260126098 A1US 20260126098A1US-20260126098-A1

Abstract

A shuttling mechanical tensioner for control of chain drives with alternating tight and slack chain strands. The shuttling mechanical tensioner allows for chain control on an outside face of the chain strand or an inside face of the chain strand.

Inventors

Paul Freemantle
Timothy K. White

Assignees

BORGWARNER, INC.

Dates

Publication Date: 20260507
Application Date: 20241106

Claims (11)

1 . A tensioner for a chain housed in a chain drive housing comprising: a rod having a first end and a second end separated by a length and a series of grooves proximate to the second end; a first face support proximal to and fixed to a first end of the rod comprising a body defining a first face support hole for receiving the rod and a first face support protrusion extending axially from the body of the first face support, perpendicular to the first face support hole; a first tensioner face pivotably mounted to the first face support protrusion applying tension to a first strand of the chain; a second face support proximal to the second end of the rod having a body defining a second face support hole for receiving the rod, a cutout on a planar surface of the body adjacent the second face support hole, and a second face support protrusion extending axially from the body of the second face support, the cutout being adjacent to the series of grooves on the rod, wherein the second face support is moveable along the rod; a second tensioner face pivotably mounted to the second face support protrusion applying tension to a second strand of the chain; a clip for engaging the series of grooves of the rod within the second face support hole and the cutout of the second face support, allowing for movement of the rod in a first direction and preventing movement of the rod in a second direction, opposite the first direction; and a bias spring biasing the second face support towards the first face support; wherein as slack in the chain increases, tension is applied to the first strand of the chain via the first tensioner face mounted to the first face support and tension is applied to the second strand of the chain by the second tensioner face mounted to the second face support moveably biased into contact by the bias spring and held in contact with the second strand of the chain by engagement of the clip with the series of grooves on the rod and the cutout of the body of the second face support.
2 . The tensioner of claim 1 , further comprising a fixed block mounted to the rod between the first face support and the second face support and fixed to the chain drive housing between the first face support and the second face support.
3 . The tensioner of claim 1 , further comprising a cap mounted to the second end of the rod, wherein the bias spring is between the cap and the second face support.
4 . The tensioner of claim 2 , further comprising an anti-rotation device mounted between the rod and the fixed block.
5 . (canceled)
6 . The tensioner of claim 1 , wherein a first tensioner face support and a second tensioner face support each comprises a body defining a hole and a chain sliding face.
7 . The tensioner of claim 6 , wherein the chain sliding face of the first tensioner face support tensions an outside surface of the first strand of the chain and the chain sliding face of the second tensioner face support tensions an outside surface of the second strand of the chain.
8 . A tensioner for a chain housed in a chain drive housing comprising: a rod having a first end and a second end separated by a length and a series of grooves proximate to the second end; a first fixed piece mounted to the first end of the rod; a second fixed piece mounted to the second end of the rod; a first face support proximal to the first end of the rod and movable about the rod comprising a body defining a first face support hole for receiving the rod and a first face support protrusion extending axially from the body of the first face support, perpendicular to the first face support hole; a first tensioner face pivotably mounted to the first face support protrusion applying tension to a first strand of the chain; a second face support proximal to the second end of the rod having a body defining a second face support hole for receiving the rod, a cutout on a planar surface of the body adjacent the second face support hole, and a second face support protrusion extending axially from the body of the second face support, the cutout being adjacent to the series of grooves on the rod, wherein the second face support is moveable along the rod; a second tensioner face pivotably mounted to the second face support protrusion applying tension to the second strand of the chain; a clip for engaging the series of grooves of the rod within the second face support hole and the cutout of the second face support allowing for movement of the rod in a first direction and preventing movement of the rod in a second direction, opposite the first direction; and a bias spring between the first moveable support and the second moveable support face; wherein as slack in the chain increases, tension is applied to the first strand of the chain via the first tensioner face mounted to the first face support biased into contact by the bias spring and tension is applied to the second strand of the chain by the second tensioner face mounted to the second face support moveably biased into contact by the bias spring and held in contact with second strand of the chain by engagement of the clip with the series of grooves on the rod and the cutout of the body of the second face support.
9 . The tensioner of claim 8 , further comprising a first fixed piece mounted the first end of the rod and fixed to the chain drive housing and a second fixed piece mounted to the second end of the rod and fixed to the chain drive housing.
10 . The tensioner of claim 8 , wherein a first tensioner support and the second tensioner support each comprises a body defining a hole and a chain sliding face.
11 . The tensioner of claim 10 , wherein the chain sliding face of the first tensioner support face tensions an inside surface of the first strand of the chain and the chain sliding face of the second tensioner support face tensions an inside surface of the second strand of the chain.

Description

BACKGROUND The present invention relates to mechanical tensioners, and more specifically to shuttling mechanical tensioners for control of chain drives with alternating tight and slack strands. Tensioning devices, such as hydraulic tensioners, are used as a control device for automotive timing drives and power transmissions drives. Automotive timing drives and power transmission drives include either a chain or belt which travels between a plurality of sprockets or pulleys. In an automotive application, the tension of the chain can vary greatly on the slack side of the chain as the chain travels between the sprockets. Likewise, the tension of the chain can further vary as the chain elongates due to wear. As a result, it is important to impart and maintain a certain degree of tension to the chain to maintain control over the chain as it travels between the sprockets. As the chain elongates due to wear, it is important to provide an adjustable tensioning member to maintain the proper chain tension and system control. SUMMARY According to one embodiment of the present invention, a tensioner for a chain housed in a chain drive housing is disclosed. The tensioner comprising: a rod having a first end and a second end separated by a length and a series of grooves proximate to the second end; a first face support proximal to and fixed to a first end of the rod comprising a body defining a first face support hole for receiving the rod and a first face support protrusion extending axially from the body of the first face support, perpendicular to the first face support hole; a first tensioner face pivotably mounted to the first face support protrusion applying tension to a first strand of the chain; a second face support proximal to the second end of the rod having a body defining a second face support hole for receiving the rod, a cutout on a planar surface of the body adjacent the second face support hole, and a second face support protrusion extending axially from the body of the second face support, the cutout being adjacent to the series of grooves on the rod, wherein the second face support is moveable along the rod; a second tensioner face pivotably mounted to the second face support protrusion applying tension to the second strand of the chain; a clip for engaging the series of grooves of the rod within the second face support hole and the cutout of the second face support, allowing for movement of the rod in a first direction and preventing movement of the rod in a second direction, opposite the first direction; and a bias spring biasing the second face support towards the first face support. As slack in the chain increases, tension is applied to a first strand of the chain via the first tensioner face mounted to the first face support and tension is applied to the second strand of the chain by the second tensioner face mounted to the second face support moveably biased into contact by the bias spring and held in contact with second strand of the chain by engagement of the clip with the series of grooves on the rod and the cutout of the body of the second face support. According to another embodiment of the present invention, a tensioner for a chain housed in a chain drive housing is disclosed. The tensioner comprising: a rod having a first end and a second end separated by a length and a series of grooves proximate to the second end; a first fixed piece mounted to the first end of the rod; a second fixed piece mounted to the second end of the rod; a first face support proximal to the first end of the rod and movable about the rod comprising a body defining a first face support hole for receiving the rod and a first face support protrusion extending axially from the body of the first face support, perpendicular to the first face support hole; a first tensioner face pivotably mounted to the first face support protrusion applying tension to a first strand of the chain; a second face support proximal to the second end of the rod having a body defining a second face support hole for receiving the rod, a cutout on a planar surface of the body adjacent the second face support hole, and a second face support protrusion extending axially from the body of the second face support, the cutout being adjacent to the series of grooves on the rod, wherein the second face support is moveable along the rod; a second tensioner face pivotably mounted to the second face support protrusion applying tension to the second strand of the chain; a clip for engaging the series of grooves of the rod within the second face support hole and the cutout of the second face support, allowing for movement of the rod in a first direction and preventing movement of the rod in a second direction, opposite the first direction; and a bias spring between the first moveable face support and the second moveable face support. As slack in the chain increases, tension is applied to the first strand of the chain via the first tensioner face mounted to the