Chain guide and chain transmission device

Patent metadata

Field	Value
Publication number	US-9400046-B2
Application number	US-201314402340-A
Country	US
Kind code	B2
Filing date	May 24, 2013
Priority date	May 24, 2012
Publication date	Jul 26, 2016
Grant date	Jul 26, 2016

Abstract

A chain guide includes roller element bearings adapted to guide, while rolling, a timing chain through which torque is transmitted. The chain guide further includes a guide base arranged along one side of the timing chain and having an opposed pair of side plates. Each side plate is formed with plural shaft engaging portions arranged so as to lie on a circular arc. The chain guide further includes roller shafts having their ends supported by the respective shaft engaging portions, and rotatably supporting the roller element bearings. An oil guide hole is formed in a wall surface of each shaft engaging portion facing the end surface of the roller shaft so as to extend through the side plate to its outer side surface.

First claim

What is claimed is:

1. A chain guide comprising:
a guide base including an opposed pair of side plates elongated in one direction and configured to be arranged along a portion of an outer periphery of a timing chain such that the one direction coincides with a direction in which the timing chain moves, wherein each of the side plates is formed with shaft engaging portions that are opposed to the respective shaft engaging portions of the other of the side plates;
a plurality of roller shafts arranged spaced apart from each other in a length direction of the side plates, and having end portions supported by the respective shaft support portions; and
a plurality of rollers rotatably supported by the respective roller shafts and configured to guide the timing chain, wherein the rollers comprise roller element bearings each including an outer race and a plurality of roller elements mounted in the outer race,
wherein oil guide holes are formed in each of the side plates at or around the respective shaft engaging portions to extend through the side plate from an inner side surface to an outer side surface, of the side plate.

2. The chain guide of claim 1 , wherein the roller shafts are formed with roller element rolling surfaces on outer peripheries of the roller shafts, wherein each of the roller element rolling surfaces is in contact at a contact portion with one of the roller elements of a corresponding one of the roller element bearings that lies in a loaded region where radial loads are applied to the one of the roller elements, and wherein the oil guide holes lie on extensions of the respective contact portions.

3. The chain guide of claim 1 , wherein the guide base is formed by molding, and wherein the oil guide holes are formed while the guide base is being formed by molding.

4. The chain guide of claim 1 , wherein each of the roller element bearings further comprises seals mounted at respective open ends of the outer race with gaps defined between radially inner surfaces of the respective seals and a radially outer surface of a corresponding one of the roller shaft, and wherein the seals are configured to prevent entry of foreign matter into the respective roller element bearings.

5. The chain guide of claim 1 , wherein each of the shaft engaging portions comprises a tapered groove section extending from an outer peripheral surface of a corresponding one of the side plates facing the timing chain in a width direction of the side plate, and a circular shaft support section connected to a narrow end of the tapered groove section and configured to support one end of one of the roller shafts, wherein the narrow end of the tapered groove section is configured to prevent the end of the roller shaft from being pulled out of the shaft support section, and wherein the oil guide holes are formed in the respective tapered groove sections.

6. The chain guide of claim 1 ,
wherein each of the shaft engaging portions comprises a tapered groove section extending from an outer peripheral surface of a corresponding one of the side plates facing the timing chain in a width direction of the side plate, and a shaft support section connected to a narrow end of the tapered groove section and configured to support one end of one of the roller shafts, and wherein for each of the shaft engaging portions:
(a) the shaft support section has on an inner periphery thereof an opposed pair of first flat surfaces which are kept in surface contact with second flat surfaces formed on an outer periphery of the one of the roller shafts at the one end thereof, thereby preventing rotation of the one of the roller shafts;
(b) the tapered groove section has side surfaces connected to ends of the respective first flat surfaces;
(c) the tapered groove section has a wall surface facing an end surface of the one of the roller shafts and formed with an anti-separation protrusion kept in engagement with the outer periphery of the one end of the one of the roller shafts; and
(d) the tapered groove section is formed with one of the oil guide holes.

7. The chain guide of claim 1 , wherein the shaft engaging portions comprise shaft holes extending through the respective side plates from one to the other side surface of each of the side plates, wherein the oil guide holes are groove-shaped oil guide holes formed in radially inner surfaces of the respective shaft holes, wherein the side plates are formed from a molten material by passing the molten material in a direction in which the shaft holes are to be arranged, such that a weld line is formed at a position downstream of each of the shaft holes.

8. The chain guide of claim 7 , wherein the molten material is a synthetic resin or a light metal.

9. The chain guide of claim 7 , wherein a ratio of L 1 to L 2 is 1/3 or less, where L 1 is a distance between a center of each of the shaft holes and one of two peripheral surfaces of a corresponding one of the side plates, and L 2 is a distance between the center of each of the shaft holes and the other of the two peripheral surfaces.

10. A chain transmission device comprising a driving sprocket, a driven sprocket, a timing chain trained around the driving sprocket and the driven sprocket, a pivotable chain guide provided on one side of a slack side of the timing chain so as to be pivotable about one end of the chain guide, and configured to guide a movement of the timing chain, and a chain tensioner configured to apply an adjusting force to a remote end of the chain guide remote from the one end of the chain guide so as to press the remote end against the timing chain,
wherein the chain guide is the chain guide of claim 1 .

11. A chain transmission device comprising a driving sprocket, a driven sprocket, a timing chain trained around the driving sprocket and the driven sprocket, a pivotable chain guide provided on one side of a slack side of the timing chain so as to be pivotable about one end of the chain guide, and configured to guide a movement of the timing chain, a chain tensioner configured to apply an adjusting force to a remote end of the chain guide remote from the one end of the chain guide so as to press the remote end against the timing chain, and a stationary chain guide provided on one side of a tension side of the chain guide and configured to guide the movement of the timing chain,
wherein at least one of the pivotable chain guide and the stationary chain guide is the chain guide of claim 1 .

Assignees

• Kato Akio
• Oishi Shinji
• Nakao Goro
• Okasaka Makoto
• Tsujimoto Takashi
• Ntn Toyo Bearing Co Ltd

Inventors

• Kato Akio
• Oishi Shinji
• Nakao Goro
• Okasaka Makoto
• Tsujimoto Takashi

Classifications

• F16H57/05

  of chains · CPC title

• F16C33/66

  Special parts or details in view of lubrication · CPC title

• F16H2007/0893

  Circular path · CPC title

• F16H2007/0874

  Two or more finally actuated members · CPC title

• F16H7/18 Primary

  Means for guiding or supporting belts, ropes, or chains (construction of pulleys F16H55/36) · CPC title