JP2016191449A - Tensioner lifter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tensioner lifter excellent in wear resistance.SOLUTION: A tensioner lifter 40 is equipped with a pressing body 42 which is energized by a first energizing member 51 so as to press a cam chain 25 of an internal combustion engine; a supporting cylinder body 41 which slidably holds the pressing body inside, and is attached to an engine body; a regulating shaft member 43 which is provided on the supporting cylinder body, and is disposed so as to intersect a sliding direction of the pressing body; and a wedge member 45 which is put between the regulating shaft member and a pressing body side surface 42w of the pressing body, and presses the pressing body side surface by a second energizing member 52 energizing in the opposite direction to the first energizing member. The wedge member has a resisting member 45b equipped with a pressing bottom surface 45bt slidably surface-contacting with the pressing body, and a sliding arc surface 45bw capable of converting the energizing force of the second energizing member into a pressing body locking force toward the pressing body side surface; and a cam member 45a which is rockably supported by the regulating shaft member, and is equipped with a cam member 45aw surface-contacts with the sliding arc surface to generate the pressing body locking force by cooperating with the sliding arc surface.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a tensioner lifter capable of adjusting a pressing force applied to a cam chain in an internal combustion engine.

  In a conventional internal combustion engine, a tensioner that extends along a cam chain that is an endless transmission is provided. A tensioner lifter is disposed as a pressing force applying device that presses the tensioner. The tensioner lifter has a pressing body that abuts the tip portion against the tensioner, and the pressing body is biased in a direction of pressing the tensioner against the cam chain. Further, the tensioner lifter has a structure that restricts the return of the pressing body to the side opposite to the pressing direction (for example, Patent Document 1).

Japanese Patent No. 4030392

The return preventing mechanism for restricting the return of the pressing body of the tensioner lifter described in Patent Document 1 includes a cam member supported by a fixed bolt so as to be swingable, and the outer peripheral curved surface of the cam member is disposed on the pressing body. These are brought into contact with a tapered portion formed in a flat surface shape. And, according to the wedge principle using the friction generated between the contact members, the cam member is sandwiched to prevent the pressing body from returning.
By the way, in this return prevention mechanism, since the outer peripheral surface of a cam member is a curved surface, since the other side of a cam member is a flat surface of a taper part, the contact location in a return prevention mechanism becomes a line contact. For this reason, there is a possibility that uneven wear may occur at the contact location, and there is room for improvement in terms of wear resistance.

  The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a tensioner lifter that suppresses uneven wear at the contact portion of the return prevention mechanism, has excellent wear resistance, and can operate stably over a long period of time. There is.

In order to achieve the above object, the invention according to claim 1
A pressing body biased by a first biasing member to press the endless transmission body of the internal combustion engine;
A supporting cylinder that is slidably held inside the pressing body and is attached to the engine body of the internal combustion engine;
A regulating shaft member provided on the support cylinder and arranged to intersect the sliding direction of the pressing body;
A wedge member that is sandwiched between the regulating shaft member and the pressing body side surface of the pressing body and presses the pressing body side surface by a second biasing member that biases in the opposite direction to the first biasing member; ,
A tensioner lifter comprising:
The wedge member is
A resistance member comprising a pressing arc bottom surface slidably contacting the pressing body and a sliding arc surface capable of converting the urging force of the second urging member into a pressing body locking force toward the pressing body side surface;
A cam member provided with an arc cam surface that is supported by the regulating shaft member so as to be swingable and that generates a pressing body locking force in cooperation with the sliding arc surface by being in surface contact with the sliding arc surface; It is characterized by having.

In addition to the structure of Claim 1, the invention according to Claim 2
The wedge member is configured such that an axis of the regulating shaft member is positioned rearward of an arc center of the sliding arc surface in an urging direction of the second urging member, and the arc with respect to the side surface of the pressing body. It is characterized by being located away from the center.

In addition to the structure of Claim 1 or 2, the invention which concerns on Claim 3 is
The resistance member is formed with a circular hole including the sliding arc surface,
The cam member is fitted in the circular hole so as to be able to rotate and slide.

In addition to the structure as described in any one of Claims 1-3, the invention which concerns on Claim 4
The resistance member is provided with a protrusion on the top.

In addition to the structure as described in any one of Claims 1-4, the invention concerning Claim 5 is
The pressing body side surface is formed on a flat surface parallel to the axis of the pressing body.

In addition to the structure of Claim 5, the invention which concerns on Claim 6 is
The flat surface is provided with a raised portion raised in the radial direction of the pressing body.

In addition to the structure of Claim 6, the invention which concerns on Claim 7 is
An engagement member that engages with the raised portion and maintains the pressed state of the pressing body into the support cylinder is detachably provided in a mounting hole formed in the support cylinder,
The mounting hole is provided so as to be exposed to the outside when the support cylinder is mounted on the internal combustion engine.

In addition to the structure of Claim 7, the invention which concerns on Claim 8 is
The engaging member is composed of a plug-in type pin member that can be inserted into and removed from the mounting hole.
The mounting hole is configured to be closed by a cap member inserted from the outside.

In addition to the structure of Claim 7, the invention according to Claim 9
The mounting hole is formed as a female screw type screw hole,
The engagement member includes a screw portion that can be screwed into the screw hole and a small diameter portion in the axial direction of the screw portion,
The engagement member is configured such that the threaded portion engages with the raised portion in a state of being screwed into the screwed hole, and the engagement with the raised portion is released by the small diameter portion when the screwing is completed. To do.

According to the first aspect of the present invention, the wedge member is a slide capable of converting the pressing bottom surface slidably contacting the pressing body and the urging force of the second urging member into a pressing body locking force toward the pressing body side surface. A resistance member having an arc surface, and an arc cam surface which is supported by the regulating shaft member so as to be swingable, and generates a pressing body locking force in cooperation with the slide arc surface by being in surface contact with the slide arc surface. By providing the cam member, the contact portion between the arc cam surface and the sliding arc surface and the contact portion between the pressing bottom surface and the pressing body side surface can all come into surface contact and press the pressing body.
Accordingly, when the wedge member generates a force for locking the pressing body, the wedge member is brought into surface contact at all contact portions to disperse the contact pressure, so that uneven wear can be suppressed. As a result, a tensioner lifter whose operation is stable over a long period of time can be provided.

  According to the invention of claim 2, the wedge member is located on the side surface of the pressing body with the axis of the regulating shaft member positioned behind the arc center of the sliding arc surface in the biasing direction of the second biasing member. As a result, the resistance member is always pressed against the pressing body via the cam member by the urging force of the second urging member. Is pressed in the return direction (pressing in the direction opposite to the urging direction by the first urging member), the wedge member can bite between the pressing body and the regulating shaft member to prevent the pressing body from returning.

According to the invention of claim 3, the resistance member is formed with a circular hole including a sliding arc surface, and the cam member is fitted in the circular hole so as to be able to rotate and slide. Can be supported by the regulating shaft member. Therefore, when the tensioner lifter is assembled, the resistance member can be reliably supported during the maintenance work, and can be prevented from falling off, thereby improving workability.
Further, since the contact surface between the resistance member and the cam member is circular, the workability is good and the surface contact can be improved, and uneven wear can be effectively suppressed.

  According to the fourth aspect of the present invention, since the resistance member is provided with the protrusion on the upper part, it can be operated by hooking the protrusion with a finger, so that the biasing force by the second biasing member is provided. It can be moved against the direction, and can be pulled out or held in the direction opposite to the direction of urging of the second urging member at the time of assembly or maintenance, and workability can be improved.

  According to the invention of claim 5, the pressing body side surface is formed on a flat surface parallel to the axial center of the pressing body, so that the contact position between the pressing body side surface and the pressing bottom surface of the resistance member, the regulating shaft member, Is constant regardless of the movement of the pressing body. Therefore, even if the pressing body moves, the resistance member does not move, the force pressing the resistance member against the pressing body becomes constant, and the frictional force between the resistance member and the pressing body can be made constant. As a result, the range in which the tensioner can be stably pressed can be expanded, and a tensioner lifter with a wide operating range of the pressing force can be provided.

  According to the sixth aspect of the present invention, since the raised portion is provided on the flat surface in the radial direction of the pressing body, the raised portion can be caught by the resistance member. As a result, the pressing body can be prevented from popping out, and the pressing body can be prevented from falling off.

  According to the seventh aspect of the present invention, the engagement member that engages with the raised portion and maintains the pressing state of the pressing body into the support cylinder is detachably provided in the mounting hole formed in the support cylinder. Thus, when the tensioner lifter is assembled and maintenance is performed, the pressing body can be locked, and workability can be improved. In addition, since the mounting hole is provided so as to be exposed to the outside when the support cylinder is mounted on the internal combustion engine, the pressing body can be easily set after mounting the tensioner lifter to the internal combustion engine. Assembling workability can be improved.

  According to invention of Claim 8, the engaging member is comprised by the insertion-type pin member which can be inserted / removed from a mounting hole, and the mounting hole is comprised so that obstruction | occlusion is possible by the cap member inserted from the outside. When the engagement member is removed and the tensioner lifter is in the set state, the mounting hole can be closed by the cap member.

  According to the invention of claim 9, the engaging member has a threaded portion that can be screwed into the screwing hole, the threaded portion includes a small-diameter portion in the axial direction thereof, and the engaging member is a raised portion. On the other hand, it is possible to engage with the screwing hole in the middle of screwing and to release the engagement with the small diameter portion when the screwing is completed. Can be set. Further, since the tensioner lifter can be set in the screwed state, the engaging member can be used as a closing member without providing a special closing member, and the number of parts and the number of work steps can be reduced.

It is a principal part longitudinal cross-sectional view in 1st Embodiment of an internal combustion engine provided with the tensioner lifter which concerns on this invention. It is an expanded sectional view of the tensioner lifter shown in FIG. It is a disassembled perspective view of the tensioner lifter in 1st Embodiment. It is the front view which looked at the tensioner lifter shown in FIG. 2 from the front (left side of FIG. 2). It is a principal part expanded sectional view which shows the latching state of the press body in the tensioner lifter of 1st Embodiment. It is a principal part perspective view of the tensioner lifter in 1st Embodiment. (A) is AA sectional drawing in FIG. 6, (b) is BB sectional drawing in (a). It is a principal part perspective view of the tensioner lifter in 2nd Embodiment. (A) is JJ sectional drawing in FIG. 8, (b) is KK sectional drawing in (a).

(First embodiment)
Hereinafter, a tensioner lifter according to a first embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 shows an internal combustion engine 1 mounted on, for example, a motorcycle. The engine main body 2 of the internal combustion engine 1 includes a crankcase 17 that rotatably supports a crankshaft 16 having an axis extending in the vehicle width direction of the motorcycle, and a cylinder block that is inclined forward and coupled to the crankcase 17. 18, a cylinder head 19 coupled to the cylinder block 18, and a head cover 20 coupled to the cylinder head 19.

  A camshaft 21 constituting a part of the valve mechanism is rotatably supported on the cylinder head 19 while having an axis parallel to the crankshaft 16. Between the crankshaft 16 and the camshaft 21, there is provided a timing transmission mechanism 22 that transmits the rotational power of the crankshaft 16 to the camshaft 21 side at a reduction ratio of 1/2, for example. The timing transmission mechanism 22 includes a drive sprocket 23 fixed to the crankshaft 16, a driven sprocket 24 fixed to one end of the camshaft 21, and an endless transmission wound around the drive sprocket 23 and the driven sprocket 24. The cam chain 25 is configured. The crankcase 17, the cylinder block 18, and the cylinder head 19 are provided with a cam chain passage 26 that causes the cam chain 25 to travel. The cam chain 25 travels in the travel direction indicated by the arrow R according to the rotation of the crankshaft 16.

  A cam chain guide 28 is in contact with the outer periphery of the tension side, which is the side pulled by the drive sprocket 23 in the cam chain 25. The cam chain guide 28 is configured to have a proper bow and a shape having moderate rigidity and elasticity, such as synthetic resin, along the cam chain 25 side. The end of the cam chain guide 28 on the crankshaft 16 side opens in a direction away from the crankshaft 16 and is supported by being fitted into a support recess 29 provided in the crankcase 17. A support surface 30 facing the opposite side of the cam chain 25 is provided on the cam shaft 21 side of the cam chain guide 28, and a contact support portion 31 that contacts the support surface 30 is provided on the cylinder head 19. . In addition, protrusions 32 having a circular cross section are integrally provided on both sides of the intermediate portion of the cam chain guide 28 near the support surface 30, and the protrusions 32 are fitted on the connecting surface of the cylinder block 18 to the cylinder head 19. A positioning recess 33 for positioning is provided.

Further, a tensioner 35 that is curved so as to swell in a substantially arcuate shape toward the cam chain 25 side is provided on the outer periphery of the cam chain 25 that is fed from the drive sprocket 23, that is, on the loose side of the cam chain 25. One end of the tensioner 35 is rotatably supported by the cylinder head 19 via a bolt 34 and is in sliding contact with the outer side (right side in the figure) of the cam chain 25. The tensioner 35 is pressed against the cam chain 25 by a tensioner lifter 40 attached to the cylinder block 18.
The tensioner lifter 40 is slidably held by the support cylinder 41 while being urged in a direction to press the tensioner 35 against the cam chain 25 and the support cylinder 41 attached to the cylinder block 18 of the engine body 2. A body 42 is provided.

The tensioner lifter 40 in this embodiment will be described in detail with reference to FIGS. 2 and 3.
As shown in FIGS. 2 and 3, the tensioner lifter 40 holds the cylindrical pressing body 42 slidably along the direction of the axis C <b> 3 of the pressing body 42 and is attached to the engine body 2. A cylindrical body 41 is provided. The support cylinder 41 includes a cylindrical tube portion 41a, an attachment flange 41b extending radially outward of the tube portion 41a at the longitudinal middle portion of the tube portion 41a, and an intersection of the attachment flange 41b and the tube portion 41a. It has a pair of holding walls 41c formed in the portion and holding a wedge member 45 described later.

  The cylinder portion 41a has an accommodation space 41h that is closed on the one end 41ab side (right side in FIG. 2) and slidably accommodates the pressing body 42, and has an open end on the other end side (left side in FIG. 2) A circular locking groove 41ag and a cut portion 41m into which a spring locking means described later is fitted are provided. A wedge accommodation hole 41g for accommodating the wedge member 45 is formed between the holding walls 41c.

The pressing body 42 housed in the housing space 41h of the tubular portion 41a is a cylindrical member having a spring housing hole 42h opened on the opposite side to the tip end portion 42t that contacts the tensioner 35. A flat surface 42wf parallel to the axis C3 of the pressing body 42 is formed on a part of the pressing body side surface 42w.
Further, the flat surface 42 wf is provided with a raised portion 42 wd raised in the radial direction of the pressing body 42. That is, the flat surface 42wf has a structure in which the pressing body side surface 42w is cut flat, and a circumferential portion of the pressing body side surface 42w is left at one end side of the flat surface 42wf (the side where the spring accommodating hole 42h is opened). Thus, a raised portion 42wd is formed which is raised from the flat surface 42wf.
Further, the pressing body 42 is urged toward the distal end portion 42 t of the pressing body 42 by the first urging member 51 inserted into the spring accommodating hole 42 h of the pressing body 42. The first urging member 51 is held by a receiving member 71 that receives one end of the first urging member 51 in the back of the accommodation space 41h.

  The attachment flange 41b is provided with attachment holes 41i above and below. Therefore, the fastening bolt 81 (see FIG. 1) is inserted into the mounting hole 41i to fix the tensioner lifter 40 to the mounting seat surface of the engine body 2.

  Each of the pair of left and right holding walls 41 c includes a bearing hole 41 ch into which the restriction shaft member 43 that supports the wedge member 45 is fitted. Further, the regulating shaft member 43 supported by the bearing hole 41ch is arranged in parallel with the mounting flange 41b. That is, the restricting shaft member 43 constitutes a shaft center C1 of a cam member 45a, which will be described later, arranged in a direction intersecting the sliding direction (shaft center C3) of the pressing body 42.

The wedge member 45 includes a cam member 45a and a resistance member 45b. The cam member 45a has an arc cam surface 45aw that can be eccentrically rotated about the axis C1 as the insertion hole 45ah is inserted into the restriction shaft member 43. On the other hand, the resistance member 45b includes a sliding arc surface 45bw that comes into surface contact with the arc cam surface 45aw and a pressing bottom surface 45bt that contacts the pressing body side surface 42w.
By the cooperation of the sliding arc surface 45bw and the arc cam surface 45aw, the urging force f2 of the second urging member 52 can be converted into a pressing force f4 toward the pressing body side surface 42w. That is, the urging force f2 of the second urging member 52 generates a counterclockwise turning force f3 of the cam member 45a, and the turning force f3 causes the sliding arc surface 45bw in contact with the arc cam surface 45aw to become the arc cam surface 45aw. As a result, a pressing force f4 for pressing the pressing body side surface 42w is generated on the pressing bottom surface 45bt.

  The resistance member 45b is provided with a protrusion 45bd on the top. This protrusion 45bd can be operated to move the wedge member 45 in the assembled state as shown in FIG. 2 in the direction opposite to the urging force f2 by hooking it with, for example, a finger.

  In this embodiment, the resistance member 45b is formed with a circular hole 45bh including a sliding arc surface 45bw, and the cam member 45a is fitted into the circular hole 45bh so as to be slidable. Here, the axial center C1 of the cam member 45a (axial center C1 of the regulating shaft member 43) is located behind the arc center C2 of the sliding arc surface 45bw in the biasing direction of the second biasing member 52 (FIG. 2). In FIG. 2) and further away from the arc center C <b> 2 (positioned on the upper side in FIG. 2). The resistance member 45b is provided with a spring receiving hole 45bi for accommodating the second urging member 52. The spring receiving hole 45bi holds the second urging member 52 so as to be parallel to the first urging member 51.

  Here, one end side of the second urging member 52 is accommodated in the spring receiving hole 45bi, and the other end side is held by a spring retainer 72 and a retainer retaining member 73 which are spring retaining means. For example, as shown in FIG. 3, the spring retainer 72 is formed in an annular shape, and has an upper end provided with a spring receiving portion 72 a that receives the second urging member 52. A locking projection 72b that can be fitted into the notch 41m is formed. Further, the retainer locking member 73 has an annular shape having a wide holding surface portion 73a that holds the upper end portion corresponding to the spring receiving portion 72a (the side opposite to the side where the second urging member 52 is disposed). It is a member. Therefore, as shown in FIG. 4, the retainer locking member 73 is fitted in the locking groove 41ag on the outer side of the spring retainer 72 (the tip side of the cylindrical portion 41a). That is, the retainer locking member 73 is configured so that the retaining surface portion 73a backs up the spring receiving portion 72a of the spring retainer 72 that supports the other end (the left side in FIG. 2) of the second urging member 52. The retainer 72 is retained so as not to come off.

The operation of the tensioner lifter 40 assembled to the engine body 2 will be described.
As shown in FIG. 2, in the tensioner lifter 40, the pressing body 42 is pressed by the first biasing member 51 toward the tensioner 35 with the biasing force f <b> 1. On the other hand, on the resistance member 45b of the wedge member 45, a pressing force f4 is generated in a direction in which the flat surface 42wf is pressed by the biasing force f2 of the second biasing member 52. The pressing force f4 for pressing the flat surface 42wf of the pressing body 42 is regulated by the pressing force applied between the arc cam surface 45aw and the sliding arc surface 45bw by the biasing force f2 of the second biasing member 52. It acts based on the rotational force f3 of the cam member 45a that attempts to rotate counterclockwise around the axis C1 of the shaft member 43.
Here, although the pressing force f4 in the direction in which the pressing body 42 is pressed is constantly generated by the resistance member 45b, the pressing body 42 is moved (projected) in the protruding direction by the first biasing member 51. Can do. That is, the wedge member 45 allows the flat body 42wf and the press bottom surface 45bt to slide with respect to the movement of the pressing body 42 in the protruding direction. Therefore, the pressing body 42 can press the tensioner 35 in a direction in which the cam chain 25 is not loosened.

On the other hand, a case where a pressing force f0 (a pressing force for pressing the pressing body 42 into the accommodation space 41h) stronger than the biasing force f1 acts against the biasing force f1 of the first biasing member 51 will be described.
In a state where the pressing bottom surface 45bt presses the flat surface 42wf of the pressing body 42, when the pressing force f0 acts against the urging force f1 of the first urging member 51, the pressing surface 42 comes into contact with the flat surface 42wf. The resistance member 45b is about to move in the same direction (move to the right in FIG. 2) by the pushing force f0. As a result, the wedge member 45 is bitten between the flat surface 42wf of the pressing body 42 and the regulating shaft member 43 due to the counterclockwise movement of the cam member 45a, and the return of the pressing body 42 (first biasing member). A pressing body locking force is generated to prevent the movement of 51 in the direction opposite to the biasing direction.

With reference to FIG. 5, the protrusion prevention structure of the press body 42 and the movement operation of the press body 42 are demonstrated.
The pressing body 42 in the present embodiment is pressed by the pressing force f4 by the second urging member 52, but as described above, the pressing body 42 moves in the direction of jumping out of the accommodation space 41h by the urging force f1 of the first urging member 51. Resulting in. However, the flat surface 42wf of the pressing body 42 is provided with a raised portion 42wd projecting higher than the flat surface 42wf, so that the resistance member 45b pressed against the flat surface 42wf is provided as shown in FIG. The rear lower end 45be can be hooked on the raised portion 42wd. This catching prevents the pressing body 42 from popping out.

  Further, when the pressing body 42 is operated so as to be pushed into the interior of the accommodating space 41h, for example, the protrusion 45bd on the upper portion of the resistance member 45b is used with a finger, as shown in FIG. It operates so as to resist the urging force f2 and operates so as to push the pressing body 42 into the interior of the accommodation space 41h. That is, by engaging the protrusion 45bd, the resistance member 45b can be prevented from biting when the pressing body 42 is pushed in, and the pressing operation of the pressing body 42 can be facilitated.

  Further, in the present embodiment, as shown in FIG. 3, the pair of holding walls 41c increases the distance between the holding walls 41c toward the spring retainer 72 side on the side where the protrusion 45bd of the resistance member 45b is formed. A tapered surface 41ct is provided. Since the taper surface 41ct is formed so that the interval between the holding walls 41c is large, when the protrusion 45bd is operated to be hooked with a finger, the protrusion 45bd can be easily hooked.

As described above, in this embodiment, the wedge member 45 changes the urging force of the pressing bottom surface 45bt and the second urging member 52 slidably contacting the pressing body 42 to the pressing body locking force toward the pressing body side surface 42w. A resistance member 45b having a slidable arcuate surface 45bw that can be converted, and a pressing member that is supported by the regulating shaft member 43 so as to be swingable and that is in surface contact with the slidable arcuate surface 45bw. By having the cam member 45a having the arc cam surface 45aw that generates the locking force, the contact portion between the arc cam surface 45aw and the sliding arc surface 45bw and the contact portion between the pressing bottom surface 45bt and the pressing body side surface 42w are The pressing body 42 can be pushed in contact with all the surfaces.
Accordingly, when the wedge member 45 generates a force for locking the pressing body 42, the wedge member 45 is in surface contact with all the contact portions and disperses the contact pressure, so that uneven wear can be suppressed. As a result, the tensioner lifter 40 whose operation is stable over a long period of time can be provided.

  In the present embodiment, the wedge member 45 is located behind the arc center C2 of the sliding arc surface 45bw in the urging direction of the second urging member 52 and presses the axis C1 of the regulating shaft member 43. As a result, it is configured to be positioned away from the arc center C2 with respect to the body side surface 42w. As a result, the biasing force f2 by the second biasing member 52 pushes the resistance member 45b through the cam member 45a to the pressing body 42 side. Therefore, when the pressing body 42 is pressed in the return direction (pressing in the direction opposite to the urging direction by the first urging member 51), the wedge member 45 is moved between the pressing body 42 and the regulating shaft member. 43, and the return of the pressing body 42 can be prevented.

Further, in the present embodiment, the resistance member 45b is formed with a circular hole 45bh including a sliding arc surface 45bw, and the cam member 45a is fitted in the circular hole 45bh so as to be able to rotate and slide. 45b can be supported by the restriction shaft member 43 through the cam member 45a. Accordingly, when the tensioner lifter 40 is assembled, the resistance member 45b can be reliably supported during maintenance work, and can be prevented from falling off, thereby improving workability.
Moreover, since the contact surface of the resistance member 45b and the cam member 45a is circular, workability is good and surface contact can be improved, and uneven wear can be effectively suppressed.

  In the present embodiment, the resistance member 45b is provided with the protrusion 45bd on the upper portion, so that the protrusion 45bd can be hooked and operated by a finger. Therefore, it can be moved against the urging direction by the second urging member 52, and can be pulled out or held in the direction opposite to the urging direction of the second urging member 52 during assembly or maintenance. And workability can be improved.

  In the present embodiment, the pressing body side surface 42w is formed on the flat surface 42wf parallel to the axis C3 of the pressing body 42, so that the pressing body side surface 42w and the pressing bottom surface 45bt of the resistance member 45b are in contact with each other. The distance between the position and the regulating shaft member 43 is constant regardless of the movement of the pressing body 42. Therefore, even if the pressing body 42 moves, the resistance member 45b does not move, the force pressing the resistance member 45b against the pressing body 42 becomes constant, and the frictional force between the resistance member 45b and the pressing body 42 can be made constant. As a result, the range in which the tensioner can be stably pressed can be expanded, and the tensioner lifter 40 with a wide operating range of the pressing force can be provided.

  Further, in the present embodiment, the flat surface 42wf is provided with a raised portion 42wd raised in the radial direction of the pressing body 42, so that the raised portion 42wd becomes the resistance member 45b (the rear lower end portion of the pressing bottom surface 45bt). 45be). As a result, the pressing body 42 can be prevented from popping out, and the pressing body 42 can be prevented from falling off.

  As shown in FIG. 6 with reference to FIG. 1, the tensioner lifter 40 of the present embodiment has a cylindrical portion 41 a on one side of the mounting flange 41 b (on the side opposite to the side on which the wedge member 45 is disposed), For example, a mounting hole 41ph into which an engaging member 48 formed of an L-shaped pin member can be inserted is provided. As shown in FIG. 7, the mounting hole 41ph is disposed in the engaging member mounting portion 41p having a thick cylindrical portion 41a and is provided so as to cross one end of the accommodation space 41h. That is, as shown in FIG. 7A, in a state where the engaging member 48 is inserted into the mounting hole 41ph, a part of the engaging member 48 can protrude into the accommodation space 41h. Therefore, as shown in FIG. 7B, a part of the engaging member 48 can be engaged with the raised portion 42 wd of the pressing body 42.

  With this configuration, for example, in a state where the pressing body 42 is pressed into the support cylinder 41, in other words, in a state where the pressing body 42 is pressed into the accommodation space 41 h, the pressing body is pressed by the engaging member 48. It can lock so that 42 may not jump out. Further, the mounting hole 41ph is exposed to the outside when the tensioner lifter 40 is mounted on the internal combustion engine 1.

  Further, in the tensioner lifter 40 of the present embodiment, after the engaging member 48 is pulled out from the mounting hole 41ph, the cap member 49 inserted from the outside is plugged into the mounting hole 41ph.

  Thus, in the present embodiment, the mounting hole formed in the support cylinder 41 is the engagement member 48 that engages with the raised portion 42wd and maintains the pressing state of the pressing body 42 into the support cylinder 41. By being detachably provided on 41ph, the pressing body 42 can be locked when the tensioner lifter 40 is assembled and maintenance is performed, and workability can be improved. In addition, since the mounting hole 41ph is provided so as to be exposed to the outside when the support cylinder 41 is mounted on the internal combustion engine 1, the engagement member 48 is removed after the tensioner lifter 40 is mounted on the internal combustion engine 1. The take-up pressing body 42 can be set in a set state, and assembling workability can be improved.

  Further, in the present embodiment, the engaging member 48 is configured by an insertion-type pin member that can be inserted and removed from the mounting hole 41ph, and is configured to be closed by a cap member 49 that is inserted from the outside. Thus, when the engagement member 48 is pulled out and the tensioner lifter 40 is set, the engagement member 48 can be removed and the cap member 49 can be inserted.

(Second Embodiment)
Hereinafter, the tensioner lifter 40 of the second embodiment of the present invention will be described with reference to FIGS. 8 and 9. In the tensioner lifter 40 of the second embodiment, the same structure as that of the first embodiment described above is denoted by the same reference numeral, description thereof is omitted, and a structure different from the first embodiment and its peripheral structure will be described. .

  As shown in FIG. 8, the tensioner lifter 40 of the present embodiment is provided with a screw-in hole 41mh into which the engaging member 58, which is a screw member, can be screwed into the cylinder part 41a. That is, the engaging member 58 has a structure that can be attached to and detached from the screw hole 41mh formed as a female screw. Here, the engagement member 58 is provided with a small diameter portion 58c having a small diameter between the engagement tip portion 58e and the screw portion 58b.

  In the case of such a structure, when the engaging member 58 is screwed into the screw hole 41mh, the screwing is stopped in the middle of screwing. As a result, as shown in FIGS. 9 (a) and 9 (b), the engagement tip 58e on the distal end side protrudes into the accommodation space 41h (as shown by the one-dot chain line shown in FIGS. 9 (a) and 9 (b)). State). Thus, the engagement tip 58e of the engagement member 58 can be engaged with the raised portion 42wd of the pressing body 42. When the engaging member 58 is screwed to the end, the small diameter portion 58c corresponds to the raised portion 42wd, so that the engaging member 58 is retracted from the raised portion 42wd, and the pressing body 42 is unlocked. The At the same time, the screw hole 41mh is closed by the engaging member 58.

  In the present embodiment, the engagement member 58 has a screw portion 58b that can be screwed into the screw-in hole 41mh. The screw portion 58b includes a small-diameter portion 58c in the middle of the axial direction. 58, the engagement tip 58e of the tip can be engaged with the raised portion 42wd in the middle of screwing into the screw hole 41mh, and the engagement can be released by the small diameter portion 58c in the screwing completed state. The locking and unlocking of the pressing body 42 can be set by the screwed state of the engaging member 58. In addition, since the tensioner lifter 40 can be set in the screwed state, the engagement member 58 can be used as a closing member without providing a special closing member, and the number of parts and the number of work steps can be reduced. it can.

The first and second embodiments of the present invention have been described above, but the present invention is not limited to this and can be modified as appropriate. For example, in the embodiment described above, the sliding arc surface 45bw of the resistance member 45b in the wedge member 45 is circular, but it may be appropriately curved as long as it is a surface that can be brought into surface contact with each other. Moreover, although the cylinder part 41a in the above-described embodiment has a bottomed structure in which one side is closed, a structure in which both ends are opened and one end side is closed by another member may be used. Moreover, although the engaging member 48 in 1st Embodiment was made into L shape, it does not need to be L shape especially. In addition, the cross-sectional shape of the engaging member 48 can be changed to a suitable shape other than circular.
In each of the above embodiments, the internal combustion engine of the motorcycle has been described, but the present invention is not limited to this.

1 Internal combustion engine 2 Engine body 25 Cam chain (endless transmission)
40 tensioner lifter 41 support cylinder 41ph mounting hole 41mh screwing hole 42 pressing body 42w pressing body side surface 42wd raised portion 42wf flat surface 43 regulating shaft member 45 wedge member 45a cam member 45aw arc cam surface 45b resistance member 45bd protrusion 45bh circular hole 45bt pressing Bottom surface 45bw Sliding arc surface 48, 58 Engaging member 51 First urging member 52 Second urging member 58b Screw portion 58c Small diameter portion C1 Axis center C2 Arc center C3 Axis center

Claims (9)

A pressing body (42) biased by the first biasing member (51) to press the endless transmission body (25) of the internal combustion engine (1);
A supporting cylinder (41) which is slidably held inside the pressing body (42) and attached to the engine body (2) of the internal combustion engine (1);
A regulating shaft member (43) provided on the support cylinder (41) and arranged to intersect the sliding direction of the pressing body (42);
A second biasing member that is sandwiched between the regulating shaft member (43) and the pressing body side surface (42w) of the pressing body (42) and biases in the direction opposite to the first biasing member (51). (52), the wedge member (45) for pressing the pressing body side surface (42w);
A tensioner lifter (40) comprising:
The wedge member (45)
A slide capable of converting the urging force of the pressing bottom surface (45bt) and the second urging member (52) slidably in surface contact with the pressing body (42) into a pressing body locking force toward the pressing body side surface (42w). A resistance member (45b) having a moving arc surface (45bw);
The pressing shaft locking force is generated in cooperation with the sliding arcuate surface (45bw) by being supported by the regulating shaft member (43) so as to be swingable and in surface contact with the sliding arcuate surface (45bw). A tensioner lifter (40) comprising a cam member (45a) having a circular arc cam surface (45aw) to be moved. In the wedge member (45), the axis (C1) of the restricting shaft member (43) has an arc center (C2) of the sliding arc surface (45bw) in the biasing direction of the second biasing member (52). The tensioner lifter (40) according to claim 1, wherein the tensioner lifter (40) is positioned rearward of the center of the circular arc (C2) with respect to the pressing body side surface (42w). The resistance member (45b) is formed with a circular hole (45bh) including the sliding arc surface (45bw),
The tensioner lifter (40) according to claim 1 or 2, wherein the cam member (45a) is fitted in the circular hole (45bh) so as to be able to rotate and slide. The tensioner lifter (40) according to any one of claims 1 to 3, wherein the resistance member (45b) is provided with a protrusion (45bd) on an upper portion thereof. The said pressing body side surface (42w) is formed in the flat surface (42wf) parallel to the axial center (C3) of the said pressing body (42), Any one of Claims 1-4 characterized by the above-mentioned. Tensioner lifter (40) as described. The tensioner lifter (40) according to claim 5, wherein the flat surface (42wf) is provided with a raised portion (42wd) raised in the radial direction of the pressing body (42). Engaging members (48, 58) that engage with the raised portions (42wd) and maintain the pressing state of the pressing body (42) into the supporting cylinder (41) are the supporting cylinder (41). Detachably provided in the mounting hole (41ph) formed in the
The tensioner lifter according to claim 6, wherein the mounting hole (41ph) is provided to be exposed to the outside in a mounting state of the support cylinder (41) to the internal combustion engine (1). 40). The engagement member (48) is composed of a plug-in type pin member that can be inserted into and removed from the mounting hole (41ph).
The tensioner lifter (40) according to claim 7, wherein the mounting hole (41ph) is configured to be closed by a cap member (49) inserted from the outside. The mounting hole (41ph) is formed as a female screw type screw hole (41mh),
The engagement member (58) includes a screw part (58b) that can be screwed into the screw hole (41mh), and a small diameter part (58c) in the middle of the screw part (58b) in the axial direction.
In the engaging member (58), the screw portion (58b) engages with the raised portion (42wd) in the middle of the screwing into the screwing hole (41mh), and when the screwing is completed, the small diameter portion (58c) The tensioner lifter (40) according to claim 7, wherein the engagement with the raised portion (42wd) is released.

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