Tsubakimoto Chain Company

IP Co., Ltd.

Tsubakimoto Kogyo Co. Ltd.

Kozo Inoue

Masahiko Konno

Tadasu Suzuki

Hiroshi Hashimoto

Osamu Yoshida

Shigekazu Fukuda

Kazuhiko Shimaya

Katsuya Nakakubo

Tsutomu Namie

Masaki Miyaji

Shuuji Matsumura

Tomokazu Kaido

Osamu Ono

Hiroshi Hayafune

Koji Yamawaki

A guide shoe is provided, which exhibits a lower level of slide resistance between a chain and a slide surface at the time of the sliding of the chain, is able to keep a sufficient lubricant on the slide surface even at the time of the starting of an engine, and produces less noise and wear. The guide shoe includes: a slide surface that slidably guides a link plate of a traveling chain; and a plurality of guide protrusions provided on the slide surface, the guide protrusions protruding in a vertical direction from the slide surface, wherein each of front surfaces of the guide protrusions is formed to have a convex curved surface at least from a part thereof on an upstream side to a top part thereof in a chain traveling direction.

Guide shoe

A cast aluminum base frame of a movable guide for a timing chain in an internal combustion engine is produced by a die in which the parting lines are located so that the shoe-engaging surface of the base frame and the pivot shaft-receiving hole are each formed by a continuous surface of the die, without oppositely pitched drafts.

Method for die casting an aluminum base frame used in a transmission device

In a sliding contact guide for a flexible power transmission medium such as a chain or belt, the guide body includes a shoe and a plate-receiving portion integrally molded as a unit from a synthetic resin. A reinforcing plate is inserted into a slot in the plate-receiving portion. A surface of the reinforcing plate is of a concavo-convex shape. The concavo-convex shape enhances the strength of the reinforcing plate without increasing the overall weight of the guide. By controlling the spacing of the bend lines forming the concavo-convex configuration, the strength of the guide can be controlled in accordance with strength requirements for different regions of the guide.

Sliding contact guide for transmission device

A guide for as transmission device such as a chain or belt, is injection molded using a sandwich-molding process. The sandwhich-molded guide comprises a slide rail on which a chain or belt slides, and a rail supporting member intergrally provided along with the slide rail. The slide rail is composed of a material the principle component of which is first polymeric material having wear resistance and heat resistance, and the rail supporting member is composed of a material the principle component of which is a second polymeric material having higher strength than the material having the first polymeric material as its principle component. The slide rail and the rail supporting member are intimately joined to each other by injection molding using the sandwhich molding process.

Sandwich-molded guide for transmission device

A movable lever for a transmission chain, which is able to pivot smoothly, and avoid seizing on its supporting shaft, comprises a unitary, molded resin lever body composed of a chain-engaging shoe and a plate-receiving portion, and a reinforcing plate in a slot in the plate-receiving portion. The plate and the plate-receiving portion have coaxial, cofastening mounting holes which receive the mounting shaft. Reinforcing ribs are provided on a side of the plate-receiving portion and their ends are notched to provide grooves which promote the flow of oil, which accumulates on the lever, toward the mounting holes so that adequate lubrication of the mounting hole in the plate is achieved.

Movable lever for transmission chain

A tensioner has a tensioner body and a plunger slidably mounted in a hollow cylindrical part of the tensioner body. A plug is screwed into a female or internal screw formed from one end of the hollow cylindrical part. A coil spring is loaded in a spring accommodating hole of the plunger and in a spring accommodating hole of the plug. The coil spring is a left hand spring. On the other hand, the direction of the plug being screwed into the tensioner body is right, which is opposite to the winding direction of the coil spring. Since the direction of the plug being screwed and the winding direction of the coil spring are different, when the plug is being screwed into the tensioner body with the coil spring held between the plug and the plunger, the coil spring slides on the bottom of the spring accommodating hole of the plunger or on the bottom of the spring accommodating hole of the plug without being caught at either end. Thus, the tensioner can be assembled very smoothly without producing powders by abrasion which may hinder smooth sliding movement of the plunger.

Tensioner

A tensioner includes a plunger stopper mechanism for holding a plunger in an inoperative position in which the plunger is retracted into a cylinder chamber formed in a tensioner body. The plunger stopper mechanism has a radial pin hole formed in the tensioner body and communicating with the cylinder chamber, an annular pin stopper groove formed in a circumference of the plunger, and a stopper pin removably inserted through the radial pin hole into the annular pin hole. The radial pin hole has a center line extending parallel to a tangent to the bottom of the annular pin stopper groove and offset from the tangent toward an open side of the annular pin stopper groove, and the annular pin stopper groove has a depth slightly greater than a diameter of the stopper pin, so that a side face of the stopper pin is held in contact with the bottom of the annular pin stopper groove. The stopper pin has a long insertion depth relative to the tensioner body and is surely held in position against removal by a contact resistance or friction acting between the side face of the stopper pin and the bottom of the annular pin stopper groove.

Tensioner with plunger stopper mechanism

A sprocket has a central through-hole for attachment of the sprocket to a rotating shaft, a boss coaxial with the through-hole, and teeth on the periphery of the sprocket. The boss has a cylindrical outer surface coaxial with the through-hole and having stepped small-diameter portions formed at opposite ends of the boas. A cushion body is in the form of a disk having an eccentric through-hole and includes an annular bearing having a cylindrical inner surface defining the through-hole, and a cushion member press-fitted over a cylindrical outer surface of the bearing. The bearing is slidably mounted on the cylindrical outer surface of the boss on each side of the teeth, and a ring-like flange is press-fitted over each stepped portion of the boss so as to prevent the cushion body from moving in the axial direction of the sprocket while allowing sliding movement of the cushion body relative to the boss. With this arrangement, the cushion body is kept in a prescribed position at all times even when the wrapping angle of a chain relative to the sprocket exceeds 180&deg;. Thus, striking noise at engagement points between the chain and the sprocket can surely be reduced by the cushion body.

Sprocket equipped with cushion body

A tensioner guide includes a stationary shoe (6) having a contact surface (6A) confronting a free span of a transmission chain (4) between a pair of sprockets (2, 3), a movable shoe (7) movable relatively to the stationary shoe (6) in a direction toward and away from the transmission chain free span, and an urging member (9) for urging the movable shoe (7) toward the transmission chain free span. The movable shoe (7) has a contact surface (7A) being pressed against and in slide contact with the transmission chain free span by the action of the urging member (9) to hold a tension in the transmission chain (4). The movable shoe (7) is movable, in response to a decrease in the tension in the transmission chain (4), to project from the contact surface (6A) of the stationary shoe (6) to take out slack in the transmission chain (4) and, in response to an increase in the tension in the transmission chain (4), to retract into the contact surface (6A) of the stationary shoe (6) to such an extent that the contact surface (6A) of the stationary shoe (6) and the contact surface (7A) of the movable shoe (7) are both in sliding contact with the transmission chain free span.

Tensioner guide for chain drive unit

A hydraulic tensioner device, which is compact in size, simple in construction and can be manufactured efficiently, has a shoe (4) for applying a tensioning force to a chain (3) or belt. The shoe has a plunger (5) which has a hollow portion (6) in which a valve block (7), a spring (9) and an inner sleeve (10) are slidably disposed. The upper end of the inner sleeve is supported within a cylindrical chamber (2) in a tensioner body (1). The tensioner body has an oil passage (11) communicating with an internal space of the inner sleeve. The bottom surface (6A) of the hollow portion and the valve block jointly define therebetween a high pressure chamber (8) filled with an oil supplied from the internal space of the inner sleeve via a check valve (7A) in the valve block. When the plunger is forced upwardly, the oil in the high pressure chamber is discharged through a clearance (S) of a small cross-sectional area defined between the respective outside surfaces of the valve block and the inner sleeve and the inside surface of the hollow portion of the plunger. By virtue of a flow resistance created during the passage of the oil through the clearance, an impact force applied from a chain (3) to a shoe (4) is absorbed.

Hydraulic tensioner having a plunger with a self-contained reservoir and

A tensioner device for a power transmission chain, which has a small number of components and hence is able to reduce the cost of manufacture and assembly, can be mounted or installed easily, and requires only a small space for installation thereof. The tensioner device consists of a tensioner lever (4) pivoted at one end thereof on a support shaft (3) disposed on a fixed member (2) and carries, on a surface thereof facing a chain (7), a shoe (8) slidably engageable with the chain (7). The opposite end of the tensioner lever (4) has formed therein a plunger receiving hole (9) having an opening (9A) facing in a direction opposite to the surface to which the shoe (8) is attached. A plunger (10) is slidably received in the plunger receiving hole (9) and is held in abutment with a stopper (17) disposed on the fixed member (2). The plunger (10) is urged in a forward direction projecting outwardly from the plunger receiving hole (9), and a unidirectional restriction device resists movement of the plunger (10) in the reverse direction.

Hydraulically damped tensioner device for power transmission chain

A device for applying tension to an endless chain, belt or the like comprises a ratcheted plunger having a substantially planar face disposed in substantially perpendicular relationship to the axis of movement of the plunger, and a chain or belt-engaging lever having a pad with a convex face arranged to contact the substantially planar face of the plunger. Vibrational forces exerted by the lever on the tensioner are substantially parallel to the axis of movement of the plunger, so that wear of the plunger and plunger guide are significantly reduced.

Growing community of inventors

Osaka, Japan

Kozo Inoue