Abstract: A fixed or adjustable chain guide includes a captured shoulder bolt fastener. An adjustable chain guide such as a chain tensioner arm assembly includes a tensioner arm with a pivot bore defined about a pivot axis. The pivot bore includes an inner end opening through a rear face of the tensioner arm and an outer end opening through a front face of the tensioner arm. The tensioner arm further includes at least one resilient fastener retaining tab located adjacent the pivot bore. The shoulder bolt extends through the pivot bore and is engaged by the at least one resilient fastener retaining tab, and the at least one fastener retaining tab inhibits separation of the fastener from the tensioner arm. The fastener preferably includes an annular groove or other recess to be engaged by the one or more fastener retaining tabs in order to permit the tensioner arm to rotate relative to the fastener.

Abstract: An inverted tooth chain drive system includes an inverted tooth chain structured for inside flank engagement. The chain includes link rows each including leading inside flanks that project outwardly relative to trailing outside flanks of a preceding link row. The system further includes a sprocket with which said inverted tooth chain is drivingly engaged. The sprocket includes a plurality of teeth circumferentially spaced about an axis of rotation, each tooth comprising an engaging flank and a disengaging flank. Some of the teeth are defined with a first tooth form in which said engaging flank thereof is defined with a first pressure angle and others of said teeth are defined with a second tooth form in which the engaging flank thereof is defined with a second pressure angle that is different from the first pressure angle in order to stagger or modulate the initial meshing impacts between the leading inside flanks of the chain and engaging flanks of the sprocket teeth.

Abstract: A sprocket and a roller chain drive system including same are disclosed. The sprocket is a random engagement sprocket comprising a first plurality of A-profile teeth formed with a first asymmetric profile and a second plurality of B-profile teeth formed with a second asymmetric profile. The A-profile teeth each define a first pressure angle and the B-profile teeth each define a second pressure angle that is at least 5 degrees greater than said first pressure angle so that a minimum separation ? is defined. The sprocket is defined with added chordal pitch reduction of 0.2% up to 1% relative to the link pitch of the associated roller chain. The sprocket can be defined with root relief and/or can comprise resilient cushion rings. Initial roller contacts made with the A-profile and B-profile teeth are modulated owing to the pressure angle separation and added chordal pitch reduction.

Abstract: A sprocket includes a hub and a plurality of teeth projecting radially outwardly from the hub. At least one cushion ring is located adjacent the teeth, and the cushion ring defines a plurality of compression pads separated from each other by transverse grooves. Each of the compression pads is defined symmetrically about a circumferential mid-point. When part of a sprocket with symmetric tooth spaces, the cushion ring is being operable identically in first and second opposite rotational directions. In one arrangement, the compression pads each include a planar outer surface having a leading and a trailing end, wherein the leading end and trailing end are located a common radial distance from a center of the hub about which the sprocket rotates. The tooth spaces of the sprocket can be symmetric, asymmetric and the root surface can be relieved. The sprocket can include multiple tooth profiles distributed randomly about the hub.

Abstract: A reduced noise and vibration chain drive system includes a sprocket with a plurality of symmetrical teeth and tooth spaces. A chain is engaged with the sprocket and includes rollers received in the tooth spaces. The root surface of each tooth space includes a modified root surface portion defined with root relief so that a roller fully seated in said tooth space contacts the root surface at first and second circumferentially spaced apart roller-seating locations but is spaced from the root surface between the first and second roller-seating locations. The sprocket is optionally defined with a reduced chordal pitch as compared to the as-built link pitch of the chain. The roller seating diameter of an inscribed circle tangent to a fully seated roller is greater than a root diameter of the sprocket.

Abstract: A chain guide, such as a fixed chain guide or a tensioner arm, includes a bracket adapted for being secured to an associated engine. The bracket includes a support surface, a leading end and a trailing end spaced from the leading end in a chain movement direction. A guide blade includes a leading end, a trailing end spaced from the leading end in the chain movement direction, a chain guide surface and an inner surface positioned adjacent the support surface of the bracket. The guide blade is selectively movable slidably on the support surface in the chain movement direction and an opposite direction between a first position where the blade is separable from the bracket and a second position where the blade is fixedly secured to the bracket.

Abstract: A sprocket for an inverted tooth chain includes at least one and typically first and second resilient cushion rings for adapted to be engaged by the guide links of an associated inverted tooth chain. The sprocket is usable with conventional inverted tooth chains and/or with a new inverted tooth chain that includes guide links for each row of the chain.

Abstract: A sprocket includes a hub and a plurality of teeth projecting radially outwardly from the hub. At least one cushion ring is located adjacent the teeth, and the cushion ring defines a plurality of compression pads separated from each other by transverse grooves. Each of the compression pads is defined symmetrically about a circumferential mid-point. When part of a sprocket with symmetric tooth spaces, the cushion ring is being operable identically in first and second opposite rotational directions. In one arrangement, the compression pads each include a planar outer surface having a leading and a trailing end, wherein the leading end and trailing end are located a common radial distance from a center of the hub about which the sprocket rotates. The tooth spaces of the sprocket can be symmetric, asymmetric and the root surface can be relieved. The sprocket can include multiple tooth profiles distributed randomly about the hub.

Abstract: A chain guide includes a bracket adapted for being secured to an engine. The bracket includes a support surface including a leading end and a trailing end, and further includes a first saw-tooth fixing element. A guide shoe includes: (i) a shoe leading end; (ii) a shoe trailing end spaced from the shoe leading end in a chain movement direction; (iii) a chain guide surface extending between the shoe leading end and the shoe trailing end and adapted for slidably supporting an associated chain moving in the chain movement direction; and, (iv) an inner surface positioned adjacent the support surface of the bracket. The guide shoe further includes a second saw-tooth fixing element that mates with the first saw-tooth fixing element of the bracket to inhibit disconnection of said the guide shoe and the bracket.

Abstract: A chain guide, such as a fixed chain guide or a tensioner arm, includes a bracket adapted for being secured to an associated engine. The bracket includes a support surface, a leading end and a trailing end spaced from the leading end in a chain movement direction. A guide blade includes a leading end, a trailing end spaced from the leading end in the chain movement direction, a chain guide surface and an inner surface positioned adjacent the support surface of the bracket. The guide blade is selectively movable slidably on the support surface in the chain movement direction and an opposite direction between a first position where the blade is separable from the bracket and a second position where the blade is fixedly secured to the bracket.

Abstract: A sprocket assembly includes a sprocket body comprising: (i) first and second hubs that project axially outward from opposite first and second axial faces; and, (ii) a plurality of teeth that extend circumferentially in a row and that project radially outward between the first and second hubs. Each of the teeth includes a drive flank and a coast flank. The drive flank and coast flank of at least some of the teeth are shaped differently from each other so as to define an asymmetric tooth profile. First and second metal cushion rings are captured and float eccentrically on the first and second hubs, respectively. The teeth are identical or multiple asymmetric tooth profiles are used on a single sprocket body and arranged in a regular or irregular pattern. The root surface between successive teeth can be relieved so that a space is defined between the root surface and a roller that bridges the root.

Abstract: A sprocket and a roller chain drive system including same are disclosed. The sprocket is a random engagement sprocket comprising a first plurality of A-profile teeth formed with a first asymmetric profile and a second plurality of B-profile teeth formed with a second asymmetric profile. The A-profile teeth each define a first pressure angle and the B-profile teeth each define a second pressure angle that is at least 5 degrees greater than said first pressure angle so that a minimum separation &Dgr; is defined. The sprocket is defined with added chordal pitch reduction of 0.2% up to 1% relative to the link pitch of the associated roller chain. The sprocket can be defined with root relief and/or can comprise resilient cushion rings. Initial roller contacts made with the A-profile and B-profile teeth are modulated owing to the pressure angle separation and added chordal pitch reduction.

Abstract: A sprocket is defined to include added chordal pitch reduction when in a new or “as-manufactured” condition. The sprocket chordal pitch Ps′ is purposefully reduced as compared to the as-built chain pitch Pc (or a theoretical maximum sprocket chordal pitch) a select amount referred to herein as “added chordal pitch reduction.” This added chordal pitch reduction is in addition to the inherent chordal pitch reduction that exists owing to manufacturing tolerances. A sprocket incorporating added chordal pitch reduction is highly desired in that it facilitates extension of the meshing time interval for an associated chain roller. The sprocket is formed to have a chordal pitch that is reduced relative to a maximum theoretical sprocket chordal pitch (or the chain link pitch) by an amount between about 0.2% and about 1% of the maximum theoretical sprocket chordal pitch.

Abstract: A chain guide, such as a fixed chain guide or a tensioner arm, includes a bracket adapted for being secured to an associated engine. The bracket includes a support surface, a leading end and a trailing end spaced from the leading end in a chain movement direction. A guide blade includes a leading end, a trailing end spaced from the leading end in the chain movement direction, a chain guide surface and an inner surface positioned adjacent the support surface of the bracket. The guide blade is selectively movable slidably on the support surface in the chain movement direction and an opposite direction between a first position where the blade is separable from the bracket and a second position where the blade is fixedly secured to the bracket.

Abstract: A sprocket for an inverted tooth chain includes at least one and typically first and second resilient cushion rings for adapted to be engaged by the guide links of an associated inverted tooth chain. The sprocket is usable with conventional inverted tooth chains and/or with a new inverted tooth chain that includes guide links for each row of the chain.

Abstract: A chain tensioner apparatus includes a mounting bracket adapted for connection to an associated engine block. The mounting bracket defines a pivot point and a support surface. A blade is connected to the bracket and includes: (i) first and second opposite end portions joined together by a central portion; (ii) a hub defined by the first end portion; and, (iii) a first end wall connecting the hub to the central portion. The hub of the blade is pivotably connected to the bracket at the pivot point and the second end of the blade abuts the support surface. The blade defines an exterior chain guide surface adapted for slidingly abutting an associated chain of an associated chain drive system. The chain tensioner apparatus further includes a tensioning spring connected to the blade, the spring having opposite first and second ends located respectively adjacent the first and second opposite end portions of the blade. The spring contacts and exerts a biasing force on the central portion of the blade.

Abstract: A chain guide includes a bracket adapted for being secured to an engine. The bracket includes a support surface including a leading end and a trailing end, and further includes a first saw-tooth fixing element. A guide shoe includes: (i) a shoe leading end; (ii) a shoe trailing end spaced from the shoe leading end in a chain movement direction; (iii) a chain guide surface extending between the shoe leading end and the shoe trailing end and adapted for slidably supporting an associated chain moving in the chain movement direction; and, (iv) an inner surface positioned adjacent the support surface of said bracket. The guide shoe further includes a second saw-tooth fixing element that mates with the first saw-tooth fixing element of said bracket to inhibit disconnection of said guide shoe and said bracket.

Abstract: A chain tensioner apparatus utilizes a synthetic plastic (e.g. nylon) bracket that permits a fastener at a pivot end of the bracket to serve as a pivot pin for a shoe sub-assembly as well as a bracket fastener. A free end fastener can be positioned very close to, or substantially below, a reaction surface of the bracket. An interlocking feature is provided at a pivot end of the bracket/shoe sub-assembly and serves to maintain an interlock of the shoe-to-bracket in cooperation with an installation pin. Additionally, a positioning feature is used at the pivot end of the bracket. In order to permit the free rotation of the shoe relative to the bracket, the pivot end of the bracket is not clamped rigidly to the engine case when a pivot end bolt is installed. Further, a dowel pin can be used at the pivot end of the bracket.

Abstract: A sprocket includes a hub and a plurality of teeth projecting radially outwardly from the hub. At least one cushion ring is located adjacent the teeth, and the cushion ring defines a plurality of compression pads separated from each other by transverse grooves. Each of the compression pads is defined symmetrically about a circumferential mid-point. When part of a sprocket with symmetric tooth spaces, the cushion ring is being operable identically in first and second opposite rotational directions. In one arrangement, the compression pads each include a planar outer surface having a leading and a trailing end, wherein the leading end and trailing end are located a common radial distance from a center of the hub about which the sprocket rotates. The tooth spaces of the sprocket can be symmetric, asymmetric and the root surface can be relieved. The sprocket can include multiple tooth profiles distributed randomly about the hub.

Abstract: A sprocket is defined to include added chordal pitch reduction when in a new or “as-manufactured” condition. The sprocket chordal pitch Ps′ is purposefully reduced as compared to the as-built chain pitch Pc (or a theoretical maximum sprocket chordal pitch) a select amount referred to herein as “added chordal pitch reduction.” This added chordal pitch reduction is in addition to the inherent chordal pitch reduction that exists owing to manufacturing tolerances. A sprocket incorporating added chordal pitch reduction is highly desired in that it facilitates extension of the meshing time interval for an associated chain roller. The sprocket is formed to have a chordal pitch that is reduced relative to a maximum theoretical sprocket chordal pitch (or the chain link pitch) by an amount between about 0.2% and about 1% of the maximum theoretical sprocket chordal pitch.