Rotary actuating hydraulic tensioner
AssigneeBorgWarner Inc.
InventorsMark MacDonald Wigsten, George L. Markley
Life of this patent
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Abstract
An engine tensioning system including tensioner arms and a rotary actuating tensioner capable of driving multiple tensioner arms making multiple chain or belt contacts. The rotary actuating tensioner has connector pins fixed to a rotating surface to which tensioner arms are attached. Rotation of this surface is accomplished through a combination of springs and hydraulic pressure. When the surface rotates, the attached tensioner arms are driven laterally against the engine chain or belt, keeping it taut.
Claims23
A power transmission chain and tensioner system for an automotive engine application, said chain tensioner and power transmission chain system comprising:
- a plurality of sprockets including at least one driving sprocket connected to a power input and at least one driven sprocket connected to a power output;
- a chain wrapped around the plurality of sprockets, the chain including at least a first strand portion having some of links being pulled by the driving sprocket and a second strand portion having some links pulling the driven sprocket;
- a source for the pressurized flow of hydraulic fluid;
- a rotary actuating hydraulic tensioner having a stationary portion and a rotatable body in operative relation to the stationary portion, the rotatable body movable about a central pivot point and in flow communication with the hydraulic fluid source;
- and
- the rotatable body having an outer face provided with at least one tensioner arm operatively connected thereto, the tensioner arm having a friction surface positioned in contact with at least one of the chain strands to exert force on the strand, and the hydraulic fluid pressure within the rotary tensioner effective to maintain the rotatable body in a position to hold the friction surface against the strand with sufficient force to provide tension in the chain.
A rotary actuating hydraulic tensioner for maintaining a desired degree of tension in a chain system in an engine comprising,
- a stationary housing and a rotatable body disposed within the housing, the rotatable body movable about a central pivot point and in flow communication with a pressurized hydraulic fluid source;
- at least one first chamber within the tensioner for receiving the pressurized hydraulic fluid, the first chamber disposed to move the rotatable body about the pivot point when pressurized by the hydraulic fluid, and
- at least one tensioner arm operatively connected to the rotatable body with at least one frictional contact surface positioned to contact at least a portion of the chain to exert force on the chain when the rotatable body is moved in a first direction relative to the tensioner arm.
The rotary actuating hydraulic tensioner of claim 11 wherein the hydraulic fluid within the first chamber is generally retained within the first chamber to resist the movement of the rotatable body in a second reverse direction when force is exerted against the tensioner arm contact surface by the chain.
A rotary actuating hydraulic tensioner for maintaining a desired degree of tension in a chain system in an engine comprising,
- a stationary housing and a rotatable body disposed within the housing, the rotatable body movable about a central pivot point and in flow communication with a high pressure hydraulic fluid source;
- a first arm and a second arm opposite the first arm, each arm movably attached to pin assemblies fixed to rotatable body;
- a first shoe disposed on the first arm to contact a slack strand of the chain, the first shoe disposed outside of the slack strand and positioned to receive the slack strand along a substantial length of the first shoe;
- a second shoe disposed on the second arm to contact a tight strand of the chain, the second shoe disposed outside the tight strand and positioned to receive the tight strand along a substantial length of the second shoe;
- the rotatable body of the actuating hydraulic tensioner movable about the pivot point to urge the first and second shoes laterally inward, relative to the chain to impart tension to said chain.
Dependencies are inferred from the claim text.