JP2009257455A - Tensioning mechanism of timing chain for engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tensioning mechanism of a timing chain for an engine achieving space saving in a space between an inner wall face of an engine block and a movable guide, and positively generating thrust and backstop force of the movable guide without requiring oil pressure by a small number of parts. <P>SOLUTION: The tensioning mechanism 100 of the timing chain for an engine is composed such that a rolling type wedge body 120 rolling in a held state between an inner wall face E1 of the engine block and the movable guide 110 abutting on the timing chain TC to guide travel is energized by an energization spring toward a pivot shaft 111 of the movable guide 110, and the thrust and the backstop force of the movable guide 110 is generated with respect to the timing chain TC. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a tension applying mechanism for an engine timing chain for applying appropriate tension to a timing chain that circulates in an engine.

  In general, as a tensioning device for applying appropriate tension to the timing chain that circulates in the engine, a plunger is projected from the front surface of the tensioner housing so as to be able to advance and retreat. There is a tensioner that presses the back surface in the vicinity of the swinging end of a tensioner lever that is rotatably supported. Further, specific methods of such a conventional tensioner are roughly divided between the tensioner housing and the tensioner lever. The ratchet spring always applies a rotational biasing force around the ratchet shaft in the direction in which the ratchet pawl meshes with the ratchet teeth of the plunger, and the engagement of these ratchet pawls with the ratchet teeth prevents displacement of the plunger in the reverse direction. The ratchet tensioner constructed in the above and the tensioner housing There is a hydraulic tensioner that is configured to the hydraulic pressure supplied to the high-pressure chamber displacement backward direction of the plunger is blocked with (e.g., Patent Documents 1 and 2).

Japanese Patent No. 3649228 (see page 1, FIG. 1) Japanese Patent No. 3841355 (refer to page 1, FIG. 1)

  However, these conventional tensioners all have a plunger that presses from a direction substantially orthogonal to the back surface of the tensioner lever, so that a sufficient stroke is required between the inner wall surface of the engine block and the tensioner lever. There is a problem in the engine layout that the engine block cannot be reduced in size by the installation space because a sufficient installation space must be secured.

  Furthermore, the conventional ratchet type tensioner has a number of parts because the main components are a tensioner housing, plunger, ratchet, plunger spring, ratchet spring, etc., and a hole for accommodating a plunger receiving hole and a ratchet spring in the tensioner housing. There is a problem in the tensioner structure that it is time-consuming to manufacture and there is a disadvantage in terms of cost because it is necessary to form a hollow portion in the plunger and to engrave ratchet teeth. It was.

  In addition, since conventional hydraulic tensioners depend on the pressure of the plunger, not only a special oil supply mechanism and hydraulic seal mechanism are required, but also the deterioration of the supply oil that tends to occur during engine operation. There were troublesome problems in oil handling such as poor supply of oil and oil.

  Therefore, the present invention solves the problems of the prior art as described above, that is, the object of the present invention is to realize space saving between the inner wall surface of the engine block and the movable guide. To provide a tension applying mechanism for an engine timing chain that reliably generates a pressing force and a backstop force of a movable guide without requiring hydraulic pressure with a small number of parts.

  The tension applying mechanism of the engine timing chain according to the first aspect of the invention is a rolling wedge body that rolls in a pinched state between the inner wall surface of the engine block and a movable guide that abuts and guides the timing chain. Is configured to generate a pressing force and a backstop force of the movable guide against the timing chain by being biased by a biasing spring toward the pivot shaft of the movable guide. To do.

  In the engine timing chain tension applying mechanism according to the second aspect of the present invention, in addition to the configuration of the first aspect of the invention, the movable guide is configured to guide and regulate the rolling wedge toward the pivot shaft. By providing the guide wall on the back surface of the guide, the above-described problems are further solved.

  In addition to the configuration of the invention according to claim 1 or 2, the tension applying mechanism for the engine timing chain of the invention according to claim 3 is arranged along the longitudinal direction of the movable guide. In addition, the above-described problem is further solved by the coil spring arranged in parallel with the inner wall surface of the engine block.

  In addition to the configuration of the invention according to claim 1 or 2, the tension applying mechanism for the engine timing chain of the invention according to claim 4 is arranged along the longitudinal direction of the movable guide. In addition, the above-described problem is further solved by being constituted by a torsion coil spring having one end fixed inside the inner wall surface of the engine block.

  In addition to the structure of the invention according to any one of claims 2 to 4, the rolling-type wedge body includes the guide wall in addition to the structure of the invention according to any one of claims 2 to 4. The above-described problems are further solved by being composed of spheres that are guided and regulated by

  In addition to the structure of the invention according to any one of claims 2 to 4, the rolling wedge body includes the guide wall in addition to the configuration of the invention according to any one of claims 2 to 4. The above-described problems are further solved by the roller having the central small-diameter portion that is guided and regulated.

Therefore, the tension applying mechanism for the engine timing chain according to the present invention can provide the following special effects by including the above-described mechanism.
That is, according to the tension applying mechanism of the engine timing chain of the present invention according to claim 1, the rolling mechanism that rolls in a pinched state between the inner wall surface of the engine block and the movable guide that contacts the timing chain and guides traveling. Compared with a tensioner in which the plunger is pressed from a direction substantially perpendicular to the back surface of the tensioner lever, because the movable wedge body is biased by the biasing spring toward the pivot shaft of the movable guide. The installation space for the urging spring is only required for the installation space that is arranged in parallel with the inner wall of the engine block, so the engine block can be reduced in size, and the parts required for the conventional ratchet mechanism and hydraulic mechanism Compared to ratchet tensioners and hydraulic tensioners that require a large number of points and production burden, rolling wedges and biasing springs Because it is installed using the inner wall surface of the lock and the back surface of the movable guide, the backstop force is reliably generated by the pressing force of the movable guide by the biasing spring and the wedge function of the rolling wedge body with a small number of parts. Can be easily achieved.

  In the engine timing chain tension applying mechanism according to the second aspect of the invention, in addition to the effect of the first aspect of the invention, the movable guide guides and regulates the rolling wedge toward the pivot shaft. By providing a guide wall on the back of the guide, the rolling wedge does not jump out of the movable guide toward the pivot axis even when it receives a sudden and excessive impact from the engine timing chain side. Since the guidance is restricted, a stable and reliable pressing force and backstop force can be generated in the movable guide.

  In the engine timing chain tension applying mechanism according to the third aspect of the present invention, in addition to the effect exhibited by the first or second aspect of the present invention, the biasing spring is disposed along the longitudinal direction of the movable guide. In addition, since the biasing force according to the extension stroke of the biasing spring is accurately added to the movable guide by the coil spring arranged in parallel with the inner wall surface of the engine block, the movable guide is engine timing. A more stable and reliable pressing force and backstop force can be generated on the chain.

  In the engine timing chain tension applying mechanism according to the fourth aspect of the present invention, in addition to the effect exerted by the first or second aspect of the present invention, the urging spring is disposed along the longitudinal direction of the movable guide. In addition, because it is composed of a torsion coil spring with one end fixed inside the inner wall surface of the engine block, an instantaneous biasing force with a shortened extension stroke of the biasing spring is accurately added to the movable guide. Even if there is a sudden change in tension in the timing chain, a quicker and more reliable pressing force and backstop force can be generated on the movable guide.

  In addition to the effect of the invention according to any one of claims 2 to 4, the rolling-type wedge body has a guide wall in addition to the effect exerted by the invention according to any one of claims 2 to 4. Since the rolling wedge body made of a sphere is urged toward the pivot shaft of the movable guide while being smoothly guided and regulated by the guide wall, the timing for the engine is configured. Smooth pressing force and backstop force can be generated against chain tension fluctuation.

  In addition to the effect of the invention according to any one of claims 2 to 4, the rolling-type wedge body has a guide wall in addition to the effect exerted by the invention according to any one of claims 2 to 4. The roller guide has a central small-diameter portion that is guided and regulated by the roller, so that the rolling wedge body made of the roller having the central small-diameter portion is smoothly guided and regulated without meandering with respect to the guide wall. Therefore, it is possible to generate a reliable and smooth pressing force and backstop force against fluctuations in the tension of the engine timing chain.

  In the engine timing chain tensioning mechanism of the present invention, the rolling wedge body that rolls in a sandwiched state between the inner wall surface of the engine block and the movable guide that abuts the timing chain and guides the traveling is provided. It is configured to generate a pressing force and backstop force of the movable guide against the timing chain by being urged by the urging spring toward the support shaft, realizing space saving between the inner wall of the engine block and the movable guide As long as the pressing force and backstop force of the movable guide can be reliably generated without requiring hydraulic pressure with a small number of parts, any specific embodiment may be used.

  For example, the tension applying mechanism for the engine timing chain according to the present invention is movable in the engine block as long as the rolling wedge body can be urged toward the pivot shaft of the movable guide in the engine block. Even if the pivot shaft of the guide is arranged at either the upper position or the lower position, there is no problem even if the mounting form is upside down.

And about the specific form of the movable guide employ | adopted by this invention, the guide wall which guide-regulates a rolling-type wedge body toward a pivot axis | shaft should just be provided in the guide back surface, and the guide wall is a guide longitudinal direction. It suffices if it is formed at both ends of the guide along the direction or at the center of the guide.
In addition, all of the specific materials may be made of resin, or the shoe that slides the timing chain may be made of resin, and the guide body that holds the shoe may be made of metal such as aluminum. good.

  The specific form of the rolling wedge employed in the present invention may be either a sphere that is guided and regulated by the guide wall or a roller that has a central small diameter portion that is guided and regulated by the guide wall. Well, in the former case, the rolling wedge made of a sphere is urged toward the pivot shaft of the movable guide while being smoothly guided and regulated by the guide wall. Smooth pressure and backstop force can be generated. In the latter case, the rolling wedge body consisting of a roller having a central small diameter portion smoothly guides and controls without meandering against the guide wall. In addition, since it is biased toward the pivot shaft of the movable guide, it is possible to generate a reliable and smooth pressing force and backstop force against fluctuations in the tension of the engine timing chain.

An engine timing chain tension applying mechanism (hereinafter referred to as a “chain tension applying mechanism”) that is Embodiment 1 of the present invention will be described with reference to FIGS.
First, FIG. 1 is a usage diagram of a chain tension applying mechanism that is Embodiment 1 of the present invention, FIG. 2 is a side view of the chain tension applying mechanism that is Embodiment 1 of the present invention, and FIG. FIG. 4 is a bottom view of the chain tension applying mechanism that is Embodiment 1 of the present invention, and FIG. 4 is a cross-sectional view taken along line AA shown in FIG.

As shown in FIG. 1, a chain tension applying mechanism 100 that is Embodiment 1 of the present invention is a timing chain that circulates between a crank-side sprocket S1 and a pair of cam-side sprockets S2 and S2 disposed in an engine. Appropriate tension is applied to the TC via the movable guide 110.
In addition, the code | symbol FG in FIG. 1 is a fixed guide for making the timing chain TC guide and run smoothly along a running track line.

  As shown in FIGS. 2 to 4, the chain tension applying mechanism 100 according to the first embodiment of the present invention is sandwiched between the inner wall surface E1 of the engine block and the movable guide 110 that abuts on the timing chain TC to guide traveling. The rolling wedge 120, which is a sphere that rolls in a state, is urged by the urging spring 130 toward the pivot shaft 111 of the movable guide 110, and the pressing force and backstop force of the movable guide 110 against the timing chain TC are obtained. Is configured to occur.

That is, the biasing spring 130 described above is a coil spring that is disposed along the longitudinal direction of the movable guide 110 and is disposed in parallel with the inner wall surface E1 of the engine block, and from the inner wall surface E1 of the engine block to the timing chain TC side. The base end portion is fixed to the protruding spring support wall E2, and the distal end portion of the rolling wedge 120 is fitted in a guide bar E3 suspended from the spring support wall E2 and positioned so as to be stretchable. The movable guide 110 is biased toward the pivot shaft 111.
As a result, the urging force F corresponding to the extension stroke of the urging spring 130 is accurately applied to the movable guide 110, so that the movable guide 110 is more stable and reliable with respect to the engine timing chain TC. The top force is generated.
The reference numeral 131 shown in FIGS. 2 to 4 is a contact pad that is provided at the tip of the urging spring 130 and reliably contacts the rolling wedge body 120.

The rolling wedge 120 described above is a sphere made of steel balls, and as shown in FIG. 4, between the pair of left and right guide walls 112, 112 formed on the movable guide 110 and the guide back surface 113. Is always supported at three points, and is guided and regulated toward the pivot shaft 111 without jumping out of the movable guide 110. Therefore, a backstop force due to the wedge function is provided between the inner wall surface E1 of the engine block and the back surface of the movable guide 110. It is surely generated.
In the movable guide 110 described above, the shoe 110A for sliding the timing chain TC is made of synthetic resin, and the guide main body 110B for holding the synthetic resin shoe 110A is made of aluminum. Further, reference TC in FIG. 4 indicates a timing chain.

  The chain tension applying mechanism 100 according to the first embodiment of the present invention obtained in this manner is rolled in a state of being sandwiched between the inner wall surface E1 of the engine block and the movable guide 110 that abuts and guides the timing chain TC. The rolling type wedge body 120 made of a moving steel ball is urged toward the pivot shaft 111 of the movable guide 110 by the urging spring 130, so that the urging spring 130 is compared with a conventional tensioner. Therefore, the engine block can be reduced in size, and the rolling wedge 120 and the biasing spring 130 made of steel balls can be achieved. Is installed using the inner wall surface E1 of the engine block and the guide back surface 113 of the movable guide 110, so that the number of parts is small and the engine Even when a sudden and excessive impact is received from the timing chain TC side, the pressing force of the movable guide 110 by the urging spring 130 and the backstop force by the wedge function of the rolling wedge 120 are stably and reliably provided. The effect is enormous, such that it can be generated and its handling can be easily achieved.

5 shows a modification of the chain tension applying mechanism 100 according to the first embodiment of the present invention, and a pair of left and right guide walls 112 formed on the movable guide 110 as shown in FIG. 112 and the guide back surface 113 are continuously formed so as to exhibit an arch-shaped cross section, and the curvature radius of the arch-shaped cross section is made larger than the radius of the rolling wedge body 120 to support only one point on the guide back surface 113. Is.
As a result, the rolling wedge body 120 made of a steel ball exerts an alignment function even when trying to meander and deviate when receiving an abrupt and excessive impact from the engine timing chain TC side, so that the centering function of the movable guide 110 is achieved. Since the central portion along the longitudinal direction always rolls, the pressing force of the movable guide 110 by the biasing spring 130 and the backstop force by the wedge function of the rolling wedge 120 can be generated more stably and reliably. It has become.

Next, a chain tension applying mechanism 200 that is Embodiment 2 of the present invention will be described with reference to FIGS.
First, FIG. 6 is a side view of a chain tension applying mechanism that is Embodiment 2 of the present invention, FIG. 7 is a bottom view of the chain tension applying mechanism that is Embodiment 2 of the present invention, and FIG. It is sectional drawing of BB shown in FIG.

The chain tension applying mechanism 200 according to the second embodiment of the present invention has the same basic structure as the chain tension applying mechanism 100 according to the first embodiment of the present invention shown in FIGS. Only the specific form of the movable wedge body 220 is different, and there is no change in the remaining structure.
Therefore, portions having the same structure as the chain tension applying mechanism 100 according to the first embodiment described above in the chain tension applying mechanism 200 according to the second embodiment of the present invention are denoted by the chain tension applying mechanism 100 according to the first embodiment described above. By replacing the description with the 100 series with the reference numeral 200, the explanation will be omitted.

Therefore, in the chain tension applying mechanism 200 according to the second embodiment of the present invention, as shown in FIGS. 6 to 8, the rolling wedge body 220 is guided and restricted to the guide wall 212 disposed at the center of the movable guide 210. It is comprised from the roller which has the center small diameter part 221 by which it is made.
In short, the central small-diameter portion 221 of the roller constituting the rolling wedge 220 is guided and regulated by the guide wall 212 of the movable guide 210, and the large diameter formed at the left and right ends of the roller constituting the rolling wedge 220. The part 222 is configured to roll on guide back surfaces 213 and 213 formed on the movable guide 210 in a pair of left and right.

  The chain tension applying mechanism 200 according to the second embodiment of the present invention thus obtained is rolled in a state of being clamped between the inner wall surface E1 of the engine block and the movable guide 210 that abuts on the timing chain TC to guide traveling. The rolling type wedge body 220 made of a moving roller is urged by the urging spring 230 toward the pivot shaft 211 of the movable guide 210, so that the urging spring 230 can be compared with a conventional tensioner. Since the installation space is sufficient only for the installation space arranged in parallel with the inner wall surface E1 of the engine block, the engine block can be reduced in size, and the rolling wedge body 220 made of rollers and the urging spring 230 are provided by the engine. Since it is installed using the inner wall surface E1 of the block and the guide back surface 213 of the movable guide 210, the number of parts is small, and Even when a sudden and excessive impact is received from the gin timing chain TC side, a reliable and smooth pressing force of the movable guide 210 by the biasing spring 230 and a backstop force due to the wedge function of the rolling wedge body 220 are obtained. The effects are enormous, as they can be generated stably and reliably and can be easily handled.

Furthermore, a chain tension applying mechanism 300 that is Embodiment 3 of the present invention will be described with reference to FIGS.
First, FIG. 9 is a side view of a chain tension applying mechanism that is Embodiment 3 of the present invention, FIG. 10 is a bottom view of the chain tension applying mechanism that is Embodiment 3 of the present invention, and FIG. It is CC sectional drawing shown in FIG.

The chain tension applying mechanism 300 according to the third embodiment of the present invention has the same basic structure as the chain tension applying mechanism 100 according to the first embodiment of the present invention as shown in FIGS. Only the specific form of 330 is different, and there is no change in the remaining structure.
Therefore, portions having the same structure as the chain tension applying mechanism 100 according to the first embodiment described above in the chain tension applying mechanism 300 according to the third embodiment of the present invention are denoted by the above-described chain tension applying mechanism 100 according to the first embodiment. By replacing the description with the 100s with the reference numbers 300, the explanation will be omitted.

  Therefore, in the chain tension applying mechanism 300 according to the third embodiment of the present invention, as shown in FIGS. 9 to 11, the urging spring 330 is disposed along the longitudinal direction of the movable guide 310 and the inner wall surface E1 of the engine block. The torsion coil spring is configured such that one end 331 is fixed inside and the other end 332 is brought into contact with and urged against the rolling wedge body 320.

  The rolling wedge 320 is a sphere made of steel balls, and is always between a pair of left and right guide walls 312 and 312 formed on the movable guide 310 and the guide back surface 313 as shown in FIG. It is supported at three points, and is guided and regulated toward the pivot shaft 311 without jumping out from the movable guide 310.

  The chain tension applying mechanism 300 according to the third embodiment of the present invention thus obtained is rolled in a state of being clamped between the inner wall surface E1 of the engine block and the movable guide 310 that contacts the timing chain TC and travels. The rolling type wedge body 320 made of a moving steel ball is urged by the urging spring 330 made of a torsion coil spring toward the pivot shaft 311 of the movable guide 310, so that compared to a conventional tensioner, Since the installation space of the urging spring 330 is sufficient only for the installation space arranged in parallel with the inner wall surface E1 of the engine block, the engine block can be reduced in size, and the rolling wedge body 320 made of steel balls A biasing spring 330 made up of a torsion coil spring is installed using the inner wall surface E1 of the engine block and the guide back surface 313 of the movable guide 310. Therefore, the number of parts is small, and even when a sudden and excessive impact is received from the engine timing chain TC, the movable guide 310 is quickly and reliably pressed and rolled by the biasing spring 330. The back stop force due to the wedge function of the mold wedge body 320 can be reliably generated, and the handling thereof can be easily achieved.

Furthermore, a chain tension applying mechanism 400 that is Embodiment 4 of the present invention will be described with reference to FIGS.
First, FIG. 12 is a side view of a chain tension applying mechanism that is Embodiment 4 of the present invention, FIG. 13 is a bottom view of the chain tension applying mechanism that is Embodiment 4 of the present invention, and FIG. It is sectional drawing of DD shown in FIG.

The chain tension applying mechanism 400 according to the fourth embodiment of the present invention has the same basic structure as the chain tension applying mechanism 200 according to the second embodiment of the present invention as shown in FIGS. Only the specific form of 430 is different, and there is no change in the remaining structure.
Therefore, portions having the same structure as the chain tension applying mechanism 200 according to the second embodiment described above in the chain tension applying mechanism 400 according to the fourth embodiment of the present invention are denoted by the chain tension applying mechanism 200 according to the second embodiment described above. By replacing the description with the number 200 with the reference number 400, the explanation is omitted.

  Therefore, in the chain tension applying mechanism 400 that is Embodiment 4 of the present invention, as shown in FIGS. 12 to 14, the biasing spring 430 is disposed along the longitudinal direction of the movable guide 410 and the inner wall surface E1 of the engine block. One end 431 is fixed inside, and the other end 432 is in contact with the rolling wedge body 420 and is urged to be biased.

The rolling wedge 420 is composed of a roller having a central small-diameter portion 421 that is guided and regulated by a guide wall 412 disposed at the central portion of the movable guide 410.
In short, the central small-diameter portion 421 of the roller constituting the rolling wedge body 420 is guided and regulated by the guide wall 412 of the movable guide 410, and the large diameter formed at the left and right ends of the roller constituting the rolling wedge body 420. The portion 422 is configured to roll on guide back surfaces 413 and 413 formed on the movable guide 410 in a pair of left and right.

  The chain tension applying mechanism 400 according to the fourth embodiment of the present invention thus obtained is rolled in a state of being sandwiched between the inner wall surface E1 of the engine block and the movable guide 410 that contacts the timing chain TC and travels. The rolling wedge body 420 made of a moving roller is biased by a biasing spring 430 made of a torsion coil spring toward the pivot shaft 411 of the movable guide 410. Since the installation space for the force spring 430 is sufficient only for the installation space arranged in parallel with the inner wall surface E1 of the engine block, the engine block can be reduced in size, and the rolling wedge body 420 composed of rollers and the torsion coil spring can be achieved. The urging spring 430 is made up of the inner wall surface E1 of the engine block and the guide back surface 413 of the movable guide 410. Therefore, even if a sudden and excessive impact is received from the engine timing chain TC side, the urging spring 430 can reliably and smoothly push the movable guide 410 with a pressing force and a rolling force. The back stop force by the wedge function of the movable wedge body 420 can be generated stably and reliably, and the handling thereof can be easily achieved.

FIG. 3 is a usage diagram of a chain tension applying mechanism that is Embodiment 1 of the present invention. The side view of the chain tension | tensile_strength provision mechanism which is Example 1 of this invention. The bottom view of the chain tension | tensile_strength provision mechanism which is Example 1 of this invention. Sectional drawing of AA shown in FIG. The figure which shows the modification of the chain tension | tensile_strength provision mechanism which is Example 1 of this invention. The side view of the chain tension | tensile_strength provision mechanism which is Example 2 of this invention. The bottom view of the chain tension | tensile_strength provision mechanism which is Example 2 of this invention. Sectional drawing of BB shown in FIG. The side view of the chain tension | tensile_strength provision mechanism which is Example 3 of this invention. The bottom view of the chain tension | tensile_strength provision mechanism which is Example 3 of this invention. Sectional drawing of CC shown in FIG. The side view of the chain tension | tensile_strength provision mechanism which is Example 4 of this invention. The bottom view of the chain tension | tensile_strength provision mechanism which is Example 4 of this invention. Sectional drawing of DD shown in FIG.

Explanation of symbols

100, 200, 300, 400 ... Chain tension applying mechanism 110, 210, 310, 410 ... Movable guide 110A, 210A, 310A, 410A ... Movable guide shoe 110B, 210B, 310B, 410B ... Guide bodies 111, 211, 311, 411,..., Movable support pivot shafts 112, 212, 312, 412, guide walls 113, 213, 313, 413, guide back surfaces 120, 320,.・ Rolling wedge (sphere)
220, 420 ・ ・ ・ Rolling type wedge (roller)
221, 421... Central small diameter portion 222, 422... Large diameter portion 130, 230... Biasing spring (coil spring)
131, 231, contact pads 330, 430, biasing spring (torsion coil spring)
331, 431 ... one end of torsion coil spring 332, 432 ... other end of torsion coil spring S1 ... crank side sprocket S2 ... cam side sprocket TC ... timing chain FG ... fixed guide E1・ Inner wall surface of engine block E2 ・ ・ ・ Spring support wall of engine block E1 ・ ・ ・ Guide bar F ・ ・ ・ Biasing force

Claims (6)

  A rolling wedge body that rolls in a sandwiched state between an inner wall surface of the engine block and a movable guide that abuts on the timing chain and guides it is urged by a biasing spring toward the pivot shaft of the movable guide. And a tension applying mechanism for an engine timing chain, wherein the mechanism is configured to generate a pressing force of a movable guide and a backstop force against the timing chain.   2. The engine timing chain tensioning mechanism according to claim 1, wherein the movable guide includes a guide wall that guides and regulates the rolling wedge toward the pivot shaft. .   The said urging | biasing spring is comprised from the coil spring arrange | positioned along with the inner wall face of an engine block while arrange | positioning along the longitudinal direction of the said movable guide, The Claim 1 or Claim 2 characterized by the above-mentioned. Tensioning mechanism for engine timing chain.   The said urging | biasing spring is comprised along the longitudinal direction of the said movable guide, and is comprised from the torsion coil spring which fixes one end in the inner wall face of an engine block, The Claim 1 or Claim 2 characterized by the above-mentioned. The tensioning mechanism of the described engine timing chain.   The tension application to the engine timing chain according to any one of claims 2 to 4, wherein the rolling wedge is formed of a spherical body that is guided and regulated by the guide wall. mechanism. 5. The engine according to claim 2, wherein the rolling wedge body includes a roller having a central small diameter portion that is guided and regulated by the guide wall. 6. Timing chain tensioning mechanism.

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