BACKGROUND

[0001] The present invention relates to tensioner arms, and more specifically to integrated tensioner arm.

[0002] Currently a hydraulic tensioner is formed separately from the tensioner arm, with the piston of the hydraulic tensioner biasing the tensioner arm towards the chain or belt. Separate hydraulic tensioners and arm require separate manufacturing of each.

SUMMARY

[0003] According to one embodiment of the present invention a tensioner arm is disclosed. The tensioner comprising: a body with a first end, a second end and a length between the first end and the second, and an oil pin. The body having: a first side with a chain sliding face; a second side, opposite the first side, with a second surface opposite the chain sliding surface; a closed ended bore extending from the second surface towards the chain sliding surface at the first end of the body; a pivot point at the second end of the body in which the body of the tensioner arm pivots about; and an oil inlet line defined within the body, extending from the second end of the body to the bore at the first end of the body, such that the oil inlet line passes through the pivot point. The oil pin is received within the pivot point. The oil pin having a body comprising: a first end; a second end opposite the first end; a plurality of lands between the first end and the second end separated by spindle portions; and an annulus defined between at least two of the plurality of lands on the spindle portion, passing through the spindle portion. When the first end of the body of the tensioner arm pivots about the pivot point receiving the oil pin in the second end of the body of the tensioner arm, the annulus of the oil pin is exposed to and allows fluid to flow from a supply of oil at the second end of the oil inlet line, through the oil inlet line, through the annulus of the oil pin and to the first end of the oil inlet line in fluid communication with the bore at the first end of the body of the tensioner arm.

[0004] According to another embodiment of the present invention, an end of a piston received by the closed end bore of the first end of the body of the tensioner arm contacts a pad. The pad has a radiused profile that is specific to the changing angle of the tensioner arm as the chain contacting the arm wears and elongates through the life of the engine.

The pad is profiled such that the contact between the pad and the end of the piston aligns the force on the piston and reduces or eliminates sideload during the life of the engine. By having the tensioner integrated into the moveable tensioner arm, the contact direction of the piston on the pad can change, thereby reducing the wear on the closed end bore receiving the piston and improving the longevity of the design as compared to a standard hydraulic tensioner with a non-changing direction of contact as well as allowing the use of the tensioner in engines that are otherwise too sensitive to the sideload otherwise produced.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Fig. 1 shows a side view of an integrated tensioner arm of an embodiment.

[0006] Fig. 2 shows a cross sectional view of the integrated tensioner arm of Fig. 1.

[0007] Fig. 3 shows a detailed cross sectional view of the piston received within the integrated tensioner arm of Figs. 1-2. [0008] Fig. 4 shows a perspective view of the integrated tensioner arm with an exploded view of the pivot pin.

[0009] Fig. 5 shows a cross-sectional perspective view of the integrated tensioner arm.

[0010] Fig. 6 shows an oil pivot pin for use with the integrated tensioner arm.

[0011] Fig. 7 shows a cross sectional view of the oil pivot pin of Fig. 6.

[0012] Fig. 8 shows a side view of an integrated tensioner arm of an alternate embodiment.

[0013] Fig. 9 shows a cross sectional view of Fig. 8.

[0014] Fig. 10 shows a bottom perspective side view of an integrated tensioner arm with a pressure fitting.

[0015] Fig. 11 shows perspective top view of an integrated tensioner arm of another embodiment. [0016] Fig. 12 shows a cross-sectional side view of Fig. 11 without the clip-on chain sliding face.

[0017] Fig. 13 shows a cross-sectional side view of Fig. 11 with the clip-on chain sliding face.

[0018] Fig. 14 shows perspective view of the second end of the integrated tensioner arm.

[0019] Fig. 15 shows a sectional view of the tensioner arm of Fig. 14.

[0020] Fig. 16 shows another embodiment of an integrated tensioner arm in which fluid is provided to the tensioner arm via a pad.

[0021] Fig. 17 shows a partial perspective view of another embodiment of an integrated tensioner arm with an oil collector.

[0022] Fig. 18 shows a partial top down view of the integrated tensioner arm of Fig. 17.

[0023] Fig. 19 shows a bottom perspective side view of an integrated tensioner arm with an outer press-fit oil channel.

DETAILED DESCRIPTION [0024] In an embodiment of the present invention, tensioner components are integrated into the functionality of the tensioner arm itself. The integrated tensioner arm of an embodiment of the present invention removes the need to machine a separate tensioner body and thus reducing the cost and simplifying the system. Furthermore, the integrated tensioner arm of the present invention allows for minimization of flow requirements for the tensioner and creates a viable, low volume, low pressure chamber.

[0025] Figures 1-5 show a schematic of an integrated tensioner arm 101 for contacting a pad 102 on an engine 103.

[0026] The pad 102 has a radiused profile 102a that is specific to the changing angle of the tensioner arm 101 as the chain contacting the arm 101 wears and elongates through the life of the engine. [0027] The integrated tensioner arm 101 can be used with timing drive systems to provide tension to a chain or belt and for hydraulic tensioner arm applications. The integrated tensioner arm 101 has a body 104 with a first side with a first surface 106a, a second side with a second surface 106b opposite the first surface 106a, a first end 105a and a second end 105b with a pivot point 107, with the first end 105a opposite the second end 105b. Adjacent the first surface 106a is a structural rib 113 to add structural stiffness to the integrated tensioner arm 101 to resist bending from the load of the chain on the integrated tensioner arm 101. Received over the first surface 106 is a snap-on or clip-on chain sliding face 150. The clip-on chain sliding face 150 has a first end 153a with a first clip 152a which fastens to the first end 105a of the body 104 and a second end 153b with a second clip 152b which fastens to the second end 150b of the body 104. The clip-on chain sliding face 150 has a chain sliding surface 153c which is in contact with a belt or chain (not shown) and an underside surface 153d in contact with the first surface 106a of the body 104. An additional clip 152c is also present and extending from the underside surface 153d to be received within the first surface 106a of the body 104.

[0028] The first end 105a of the integrated tensioner arm 101 has a bore 109 for receiving a hollow piston 108. Along the length of the bore 109 is a cutout 111. Bore 109 is preferably a closed end bore.

[0029] The hollow piston 108 has a closed first end 108a for contacting the pad 102 connected to a second open end 108b with a length 108c between the closed first end 108a and the second open end 108b defining an interior 108e. The closed first end 108a preferably has a vent 110. Also along the length 108c is an oil inlet 108d which allows the flow of fluid into the interior 108e of the piston. A low pressure chamber 121 is preferably formed between the interior 108e of the piston and the bore 109. The oil inlet 108d is preferably aligned with the cutout 111 of the bore 109. The oil inlet 108d is connected through the cutout 111 of the bore 109 to an interior oil inlet line 112 extending along the length of the body 104 of the tensioner arm 101.

[0030] The contact between the pad 102 and the closed first end 108a of the hollow piston 108 aligns the force on the piston 108 and reduces or eliminates sideload during the life of the engine based on the radiused profile 102a of the pad 102. By having the hollow piston 108 of the hydraulic tensioner integrated into the moveable tensioner arm 101, the contact direction of the hollow piston 108 on the pad 102 can change, thereby reducing the wear on the bore 109 receiving the hollow piston 108.

[0031] It should be noted that a coil spring may be present within the interior 108e of the piston 108 and the low pressure chamber 121 and is not shown for clarity. Additional components that could additionally be present in the interior 108e of the piston 108 and the bore 109 are a check valve and a pressure relief valve. Additionally, while not shown, the outer diameter of the piston can contain grooves which can interact with a pawl or a tensioner clip to limit the outward movement of the piston 108 from the bore 109.

[0032] The interior oil inlet line 112 has a first end 112a connected to the cutout 111 of the bore 109 and a second end 112b at the second end 105b of the integrated tensioner arm body 104. The second end 112b of the interior oil inlet line 112 is connected to an inlet oil supply (not shown). Adjacent the second end 112b of the interior oil inlet line 112 is bore 115 at the pivot point 107. In order for fluid to flow from the inlet oil supply to the first end 112a connected to the cutout 111, fluid has to pass through the oil pin 116.

[0033] The pivot point bore 107 of the integrated tensioner arm 101 has a bore 115 which receives an oil pin 116. The bore 115 and oil pin 116 are present between the first end 112a and the second end 112b of the interior inlet line 112. The integrated tensioner arm 101 pivots about the oil pin 116. Referring to Figures 6-7, the oil pin 116 has a series of lands 117a-117d separated by spindle portions 118a-118c and an annulus 119. From a first end 116a to a second end 116b of the oil pin 116 is a first land 117a, a first spindle 118a, a second land 117b, a second spindle 118b with an annulus 119, a third land 117c, a third spindle 118c and a fourth land 117d.

[0034] In an alternate embodiment, at least the first spindle 118a receives an O-ring to seal the oil pin 116 against the bore 115 of the integrated tensioner arm 101.

[0035] In another alternate embodiment, the first spindle 118a and the second spindle 118b each receive O-rings to seal the oil pin 116 against the bore 115 of the integrated tensioner arm 101.

[0036] In yet another embodiment, the first spindle 118a, the second spindle 118b and the third spindle 118c each receive O-rings to seal the oil pin 116 against the bore 115 of the integrated tensioner arm 101. [0037] As the integrated tensioner arm 101 pivots about the pivot point bore 107, the position of the annulus 119 changes relative to body 104 of the integrated tensioner arm 101 and thus the interior oil inlet line 112, to always allow fluid to flow from supply, through the annulus 119 to the interior oil inlet line 112. Furthermore, the integrated tensioner arm 101“floats” on the oil pin 116, such that the integrated tensioner arm 101 is free to slide along the length of the oil pin 116 between the first end 116a and the second end 116b. The integrated tensioner arm 101 is maintained on the oil pin 116 by the contact between the first end 108a of the piston 108 with the radiused profile 102a of the pad 102 as well as the contact of the chain on the chain sliding surface 106a.

[0038] In this embodiment, the interior oil inlet line passes 112 through a separated portion 126 of the tensioner arm body 104 that is separated from the tensioner arm body 104 on the second side that contains the bore 109 receiving the piston 108, defining a cavity 125 between the bore 109 and the separated portion 126. The separated portion 126 of the body 104 is preferably at an angle relative to the bore 109 to allow for oil to be received by the annulus 111.

[0039] The integrated tensioner arm 101 can be made of cast aluminum or nylon plastic with a metal insert present in the bore 109 receiving the piston 108 to reduce wear between the piston 108 and the bore 109.

[0040] Figures 8-9 show an alternate embodiment in which the interior inlet passage 212 is present in the body 204 of the integrated tensioner arm 201, is curved, and does not pass through a separated portion of the tensioner body. The curved interior inlet passage 212 is preferably formed with a tool having a curving slide that enters the integrated tensioner 201 arm at a constant radius during casting of the integrated tensioner arm 201 and is then removed.

[0041] As in the first embodiment shown in Figures 1-5, the integrated tensioner arm 201 contacts a pad 102 of an engine 103. The integrated tensioner arm 201 can be used with timing drive systems to provide tension to a chain or belt and for hydraulic tensioner arm applications. The integrated tensioner arm 201 has a body 204 with a first side with a first surface 206a, a second side with a second surface 206b opposite the first surface 206a, a first end 205a and a second end 205b with a pivot point 207, with the first end 205a opposite the second end 205b. [0042] Adjacent the first surface 106a is a structural rib 113 to add structural stiffness to the integrated tensioner arm 201 to resist bending from the load of the chain on the integrated tensioner arm 201. Received over the first surface 106 is a snap-on or clip-on chain sliding face 150. The clip-on chain sliding face 150 has a first end 153a with a first clip 152a which fastens to the first end 105a of the body 204 and a second end 153b with a second clip 152b which fastens to the second end 150b of the body 204. The clip-on chain sliding face 150 has a chain sliding surface 153c which is in contact with a belt or chain (not shown) and an underside surface 153d in contact with the first surface 106a of the body 104. An additional clip 152c is also present and extending from the underside surface 153d to be received within the first surface 106a of the body 204.

[0043] The first end 105a of the integrated tensioner arm 101 has a bore 109 for receiving a hollow piston 108. Along the length of the bore 109 is a cutout 111. Bore 109 is preferably a closed end bore.

[0044] The integrated tensioner arm 201 can be made of cast aluminum or nylon plastic with a metal insert present in the bore 109 receiving the piston 108 to reduce wear between the piston 108 and the bore 109.

[0045] While just an oil pin 116 is shown in Figures 1-9, a hosed connection as shown in Figure 10 can be added to the pivot point bore 107. Within the pivot point bore 107 is the pivot pin 116 with a pressure fitting 307 present on top of the first end 116a of the pivot pin 116, sealing the pivot pin 116 under pressure within the pivot point bore 107. The pressure fitting 307 can include a nut 301, a spacer 302 and a washer 303 which is connected to a tube 304 in fluid communication with the oil supply.

[0046] Fig. 19 another embodiment in which the oil path is moved from being internal to the tensioner arm as in Figures 1-5 and 8-9 to being through a press fit metal tube 760 external to the body 704 of the tensioner arm 701. The press fit metal tube 760 has a first end 760a in fluid communication with the bore 109 housing the piston 108 and a second end 760b connected to the pivot point bore 107 with a pressure fitting 762.

[0047] Figs. 11-15 show an integrated tensioner arm 401 of another embodiment in which an oil channel 412 is present on a top, first surface 406a of the tensioner arm 401. [0048] The integrated tensioner arm 401 can be used with timing drive systems to provide tension to a chain or belt and for hydraulic tensioner arm applications. The integrated tensioner arm 401 has a body 404 with a first side with a first surface 406a, a second side with a second surface 406b opposite the first surface 406a, a first end 405 a and a second end 405b with a pivot point 407, with the first end 405a opposite the second end 405b. Adjacent the first surface 406a is a pair of structural ribs 413, 414 to add structural stiffness to the integrated tensioner arm 401 to resist bending from the load of the chain on the integrated tensioner arm 401.

[0049] The first end 405a of the integrated tensioner arm 401 has a bore 409 for receiving a hollow piston 408. Along the length of the bore 409 is a cutout 411.

[0050] The hollow piston 408 has a closed first end 408a for contacting a pad 102 and is connected to a second open end 408b with a length 408c between the closed first end 408a and the second open end 408b defining an interior 408e. Along the length 408c of the outer circumference of the hollow piston 408 are a series of grooves 408f. The closed first end 408a preferably has a vent 410. A tensioner clip 430 present within the cutout 411 and engages the series of grooves 408f on the outer circumference of the hollow piston 408.

[0051] Fluid is supplied from the bore 409 into a pressure chamber 421 formed between the interior 408e of the piston and the bore 409. It should be noted that a coil spring may be present within the interior 408e of the piston 408 and the pressure chamber 421 and is not shown for clarity.

[0052] Present on the first surface 406a and extending between the first end and the second end is an oil inlet channel 412. The oil inlet channel 412 has a first oil inlet hole 412a in fluid communication with a bore 409 receiving the piston 408 and a second oil inlet hole 412b in fluid communication with bore 415 at the pivot point 407. In order for fluid to flow from the inlet oil supply to the first end 412a connected to the cutout 411, fluid has to pass through the oil pin 116.

[0053] Received over the first surface 406a is a snap-on or clip-on chain sliding face 450. The clip-on chain sliding face 450 has a first end 453a with a first clip 452a which fastens to the first end 405a of the body 404 and a second end 453b with a second clip 452b which fastens to the second end 450b of the body 404. The clip-on chain sliding face 450 has a chain sliding surface 453c which is in contact with a belt or chain (not shown) and an underside surface 453d in contact with the first surface 406a of the body 404. An additional clip 452c is also present and extending from the underside surface 453d to be received within the first surface 406a of the body 404.

[0054] The contact between the pad 102 and the closed first end 408a of the hollow piston 408 aligns the force on the piston 408 and reduces or eliminates sideload during the life of the engine based on the radiused profile 102a of the pad 102. By having the hollow piston 408 of the hydraulic tensioner integrated into the moveable tensioner arm 401, the contact direction of the hollow piston 108 on the pad 102 can change, thereby reducing the wear on the bore 409 receiving the hollow piston 408.

[0055] The pivot point bore 407 of the integrated tensioner arm 401 has a bore 415 which receives an oil pin 116. The bore 415 and oil pin 116 are present between the first end 412a and the second end 412b of the oil inlet channel 412. The integrated tensioner arm 401 pivots about the oil pin 116. Referring to Figures 6-7, the oil pin 116 has a series of lands 117a-117d separated by spindle portions 118a-118c and an annulus 119. From a first end 116a to a second end 116b of the oil pin 116 is a first land 117a, a first spindle 118a, a second land 117b, a second spindle 118b with an annulus 119, a third land 117c, a third spindle 118c and a fourth land 117d. In an alternate embodiment, at least the first spindle 118a receives an O-ring to seal the oil pin 116 against the bore 415 of the integrated tensioner arm 101. In alternate embodiments, the first spindle 118a and the second spindle 118b each receive O-rings to seal the oil pin 116 against the bore 415 of the integrated tensioner arm 401. In yet another embodiment, the first spindle 118a, the second spindle 118b and the third spindle 118c each receive O-rings to seal the oil pin 116 against the bore 415 of the integrated tensioner arm 401.

[0056] As the integrated tensioner arm 401 pivots about the pivot point bore 107, the position of the annulus 409 changes relative to body 404 of the integrated tensioner arm 401 and thus the oil inlet channel 412 always allows fluid to flow from inlet oil supply, through the annulus 409 to the oil inlet channel 412. Furthermore, the integrated tensioner arm 401“floats” on the oil pin 116, such that the integrated tensioner arm 401 is free to slide along the length of the oil pin 116 between the first end 116a and the second end 116b. The integrated tensioner arm 401 is maintained on the oil pin 116 by the contact between the first end 108a of the piston 108 with the radiused profile 102a of the pad 102 as well as the contact of the chain on the chain sliding surface 406a.

[0057] The integrated tensioner arm 401 can be made of cast aluminum or nylon plastic with a metal insert present in the bore 409 receiving the piston 408 to reduce wear between the piston 408 and the bore 409.

[0058] Fig. 16 shows another embodiment of an integrated tensioner arm in which fluid is provided to the tensioner arm via a pad.

[0059] The integrated tensioner arm 501 can be used with timing drive systems to provide tension to a chain or belt and for hydraulic tensioner arm applications. The integrated tensioner arm 501 has a body 504 with a first side with a first surface 506a, a second side with a second surface 506b opposite the first surface 506a, a first end 505a and a second end 505b with a pivot point (not shown) for receiving a pivot pin (not shown), with the first end 505a opposite the second end 505b. Adjacent the first surface 506a is a pair of structural ribs 513 to add structural stiffness to the integrated tensioner arm 501 to resist bending from the load of the chain on the integrated tensioner arm 501.

[0060] The first end 505a of the integrated tensioner arm 501 has a bore 509 for receiving a hollow piston 508. Along the length of the bore 509 is a cutout 511. The hollow piston 508 has a closed first end 508a for contacting a pad 502 and is connected to a second open end 508b with a length 508c between the closed first end 508a and the second open end 508b defining an interior 508e. Along the length 508c of the outer circumference of the hollow piston 508 are a series of grooves 508f. The closed first end 508a preferably has a passage 510. The passage 510 could include a one-way valve or other restriction such as a wormhole. A tensioner clip 530 present within the cutout 511 and engages the series of grooves 508f on the outer circumference of the hollow piston 508.

[0061] The pad 502 has a radiused profile 502a which contacts the closed first end 508a of the hollow piston 508. Along the radiused profile 502a and aligned with the passage 510 of the hollow piston 508 is an oil inlet passage 502b connecting to an oil inlet supply (not shown) through inlet hole 502c. [0062] In this embodiment, oil is introduced from the oil inlet supply to the interior 408e of the hollow piston 408 between the contact point of the pad 502 along the radiused profile 502a at the passage 510 and the inlet hole 502c, removing the need to add oil flow through the pivot point of the tensioner arm as in other embodiments or the arm of the tensioner arm.

[0063] Additionally, the contact between the pad 502 and the closed first end 508a of the hollow piston 408 aligns the force on the piston 508 and reduces or eliminates sideload during the life of the engine based on the radiused profile 502a of the pad 102. By having the hollow piston 508 of the hydraulic tensioner integrated into the moveable tensioner arm 501, the contact direction of the hollow piston 508 on the pad 502 can change, thereby reducing the wear on the bore 509 receiving the hollow piston 508.

[0064] Figs. 17-18 show another embodiment of an integrated tensioner arm with an oil collector. In this embodiment, an oil collection bucket 650 is attached to the body 604 of the tensioner arm 601 to collect oil passively in an opening 650a of the oil collection bucket 650 during running of the engine. The oil collection bucket 650 is in fluid communication with bore 609 housing the piston 608. As in other embodiments, the closed first end 608a of the piston 608 contacts a radiused pad 102. The pad 102 has a radiused profile 102a that is specific to the changing angle of the tensioner arm 601 as the chain contacting the arm 601 wears and elongates through the life of the engine.

[0065] The contact between the pad 102 and the closed first end 608a of the hollow piston 608 aligns the force on the piston 608 and reduces or eliminates sideload during the life of the engine based on the radiused profile 102a of the pad 102. By having the hollow piston 608 of the hydraulic tensioner integrated into the moveable tensioner arm 101, the contact direction of the hollow piston 608 on the pad 102 can change, thereby reducing the wear on the bore 609 receiving the hollow piston 608.

[0066] Accordingly, it is to be understood that the embodiments of the invention herein described are merely illustrative of the application of the principles of the invention. Reference herein to details of the illustrated embodiments is not intended to limit the scope of the claims, which themselves recite those features regarded as essential to the invention.