JP2011241772A - Startup turning force transmission mechanism of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable accurate suppression of leakage of oil to the outside through a space between a flange and an inner race, in a startup turning force transmission mechanism of an internal combustion engine having the tubular inner race connected by a coupling shaft to the flange provided at an end of an engine output shaft.SOLUTION: The startup turning force transmission mechanism includes, in annular space formed by an inner peripheral surface 31 of an outer race 30 and an outer peripheral surface 21 of the inner race 20, sequentially from an engine body EB side, a one-way clutch 40, a ball bearing 50, and an inner side sealing member 60. On an outer peripheral surface 12a of the flange 12 of a crankshaft 10, a helical groove is formed along the outer peripheral surface 12a. On an inner peripheral surface 24a of the inner race 20 opposed to the outer peripheral surface 12a, a helical groove is formed along the inner peripheral surface 24a. The groove of the outer peripheral surface 12a and the groove of the inner peripheral surface 24a are mutually engaged to constitute an engaging part for suppressing passage of oil.

Description

  The present invention relates to a starting torque transmission mechanism for an internal combustion engine that transmits a torque of a starter to an engine output shaft via a one-way clutch.

  Conventionally, as a starting torque transmission mechanism of this type of internal combustion engine, for example, there is one described in Patent Document 1. In the mechanism described in Patent Document 1, the rotational force of the starter is transmitted from a ring gear to a crankshaft that is an engine output shaft of an internal combustion engine via a one-way clutch. A ball bearing that rotatably supports the ring gear is provided between the ring gear and the crankshaft. In addition, a seal member is provided on the outer periphery of the ball bearing and the one-way clutch to prevent oil supplied to the ball bearing and the one-way clutch from leaking to the outside. Thus, by providing the ball bearing, the one-way clutch, and the seal member along the radial direction of the crankshaft, the physique in the axial direction of the internal combustion engine including the starting torque transmission mechanism can be reduced.

JP 2007-247561 A

  Incidentally, when the conventional starting torque transmission mechanism described in Patent Document 1 is applied to, for example, a large displacement internal combustion engine, there are the following concerns. That is, generally, as the displacement of the internal combustion engine increases, the diameter of the crankshaft increases, and the distance from the center of the crankshaft to the seal member increases. Therefore, the rotation radius of the seal member is increased and the peripheral speed is also increased. As a result, frictional heat generated at the sliding portion of the seal member increases, resulting in thermal deterioration of the seal member and, consequently, a decrease in sealing performance.

  Therefore, as shown in FIG. 3, a one-way clutch 140, a ball bearing is disposed between the outer peripheral surface 121 of the inner race 120 and the inner peripheral surface 131 of the outer race 130 in order from the engine body EB side along the axial direction of the crankshaft 110. The structure which arrange | positions 150 and the sealing member 160 is considered. Here, an inner race 120 is connected to a flange portion 112 provided at one end of the crankshaft 110 via a bolt 103 </ b> A provided along the center axis of the crankshaft 110. A ring gear 170 is connected to an outer race 130 provided on the outer periphery of the inner race 120 via a bolt 103B. Specifically, the inner race 120 includes an inner peripheral surface 124a that faces the outer peripheral surface 112a of the flange portion 112, and an outer end surface 112b that is an end surface on the side away from the engine body EB in the flange portion 112, that is, the end surface on the transmission TM side. And an inner end face 122b opposite to each other. In the state where the inner race 120 is assembled to the crankshaft 110, the inner end surface 122b is in contact with the outer end surface 112b.

  Here, in order to improve the ease of assembling the inner race 120 to the crankshaft 110, there is a gap over the entire circumference between the outer peripheral surface 112a of the flange portion 112 and the inner peripheral surface of the inner race 120 opposed thereto. G is formed. A plurality of bolts 103 </ b> A are provided at equal intervals in the circumferential direction of the crankshaft 110.

  According to such a configuration, the distance from the center of the crankshaft 110 to the seal member 160 can be shortened, and the rotation radius of the seal member 160 can be reduced. As a result, the peripheral speed of the seal member 160 can be reduced, the frictional heat generated at the sliding portion of the seal member 160 can be reduced, and the deterioration of the sealing performance by the seal member 160 can be suppressed.

  In such a configuration, the oil chamber S is defined by the ball bearing 150, the inner peripheral surface 131 of the outer race 130, the outer peripheral surface 121 of the inner race 120, and the seal member 160. Then, it is conceivable to supply oil to the oil chamber S through the one-way clutch 140 and the ball bearing 150 by injecting and supplying oil from the oil jet mechanism OJ to the one-way clutch 140 and the ball bearing 150. The sliding portion of the seal member 160 can be lubricated and cooled by the oil supplied to the oil chamber S in this way.

  By the way, in such a starting torque transmission mechanism of an internal combustion engine, as described above, the outer peripheral surface 112a of the flange portion 112 is opposed to this for the purpose of improving the assembly of the inner race 120 to the crankshaft 110. A gap G is formed between the inner race 120 and the inner circumferential surface over the entire circumference. Further, the end surface 112b of the flange portion 112 and the end surface 122b of the inner race 120 opposite to the end surface 112b are brought into pressure contact with each other by the axial force of the bolt 103A, thereby preventing oil from leaking to the outside through the end surfaces 112b and 122b. I am doing so. However, in practice, there is a gap between the end faces 112b and 122b, and there is a concern that oil leaks outside through the gap.

  The present invention has been made in view of such circumstances, and an object of the present invention is to start rotation of an internal combustion engine including a cylindrical inner race connected by a connecting shaft to a flange portion provided at one end of an engine output shaft. An object of the present invention is to provide a starting torque transmission mechanism for an internal combustion engine that can accurately prevent oil from leaking to the outside through a flange portion and an inner race.

Hereinafter, means for solving the above-described problems and the effects thereof will be described.
(1) The invention described in claim 1 includes an inner peripheral surface facing an outer peripheral surface of a flange portion provided at one end of the engine output shaft, and an outer end surface which is an end surface on the side away from the engine body in the flange portion. A cylindrical inner race that is connected to the flange portion by a connecting shaft, and an outer race that is provided on the outer periphery of the inner race to transmit the rotational force of the starter. A bearing provided in an annular space formed by an inner circumferential surface of the outer race and an outer circumferential surface of the inner race, and supporting the outer race so as to be rotatable relative to the inner race; and the bearing in the annular space; A one-way clutch that is arranged in parallel and allows transmission of rotational force from the outer race to the inner race; and the bearing in the annular space A starting rotational force transmission mechanism for an internal combustion engine comprising a seal member that defines an oil chamber in a portion farther from the engine body than the one-way clutch, wherein the outer peripheral surface of the flange portion and the inner surface facing the outer peripheral surface The gist of the invention is that the inner peripheral surface of the race is formed with engaging portions that engage with each other to suppress the passage of oil.

  According to this configuration, unlike the configuration in which a gap is formed over the entire circumference between the outer peripheral surface of the flange portion of the engine output shaft and the inner peripheral surface of the inner race facing this, the outer peripheral surface of the flange portion and this The engaging portion serves as a barrier for oil that attempts to pass between the inner peripheral surfaces of the opposing inner races. For this reason, the infiltration of oil between the outer end face of the flange portion and the inner end face of the inner race is suppressed. Therefore, oil can be prevented from leaking outside through the gap between the flange portion and the inner race.

  (2) The invention according to claim 2 is the starting rotational force transmission mechanism for the internal combustion engine according to claim 1, wherein the inner race opens to the end surface of the inner race on the side close to the engine body. The gist thereof is that a supply passage for supplying oil to the oil chamber is formed.

  In order to supply oil to the oil chamber from the outside via the one-way clutch and the bearing in the starting torque transmission mechanism of the internal combustion engine, it is necessary to supply a sufficient amount of oil to the one-way clutch and the bearing by an oil jet or the like. There is. However, in this case, an excessive amount of oil is supplied to the one-way clutch and the bearing, and the oil is agitated with the rotation of the one-way clutch and the bearing, thereby increasing the rotational resistance. .

  Further, in such a starting torque transmission mechanism, the oil once flowing into the one-way clutch, the bearing, and the oil chamber tends to stay difficult to be discharged from them, so that the retained oil contains a lot of sludge. It becomes a state. As a result, the lubrication performance of the oil is reduced, poor lubrication of the one-way clutch, the bearing and the seal member occurs, and the oil in the oil chamber stays and the temperature rises, thereby reducing the cooling efficiency of the seal member. This will cause inconvenience.

  In this regard, according to the above configuration, oil is supplied to the oil chamber through the supply passage formed in the inner race. For this reason, oil can be supplied to the oil chamber without supplying excessive oil to the one-way clutch and the bearing, and an increase in rotational resistance of the one-way clutch and the bearing can be suppressed. Further, poor lubrication of the one-way clutch, the bearing and the seal member, and a decrease in cooling efficiency of the seal member can be suppressed.

  (3) The invention according to claim 3 is the starting rotational force transmission mechanism of the internal combustion engine according to claim 1 or 2, wherein the engaging portion is formed on the outer peripheral surface of the flange portion and the same. An outer groove that forms a spiral along the outer peripheral surface, and an inner groove that is formed on the inner peripheral surface of the inner race and engages with the outer groove while forming a spiral along the inner peripheral surface. Is the gist.

  According to this configuration, the inner race can be assembled to the flange portion by rotating the inner race with respect to the flange portion and engaging the outer groove portion and the inner groove portion. Therefore, the engaging portion can be realized without impairing the assembling property of the inner race with respect to the engine output shaft.

  (4) According to a fourth aspect of the present invention, in the starting torque transmission mechanism for an internal combustion engine according to the third aspect, the outer groove portion and the inner groove portion are arranged so that the outer groove portion and the inner groove portion are rotated along with the rotation of the engine output shaft. The gist is that the fastening force with the groove is increased.

  According to this configuration, the fastening force between the outer groove portion and the inner groove portion increases with the rotation of the engine output shaft, so that the fastening force between the outer groove portion and the inner groove portion decreases as the engine operates, and the outer groove portion and the inner groove portion become smaller. An increase in the space between the grooves can be suppressed. Accordingly, it is possible to more accurately suppress the oil from passing between the outer groove portion and the inner groove portion.

  (5) The gist of the invention described in claim 5 is that, in the starting rotational force transmission mechanism of the internal combustion engine according to claim 1 or 4, the engagement portion is further coated with a liquid gasket. It is said.

  According to this configuration, since the space between the outer peripheral surface of the flange portion and the inner peripheral surface of the inner race facing the flange portion is filled with the liquid gasket, oil is provided between the outer peripheral surface and the inner peripheral surface. Passing through can be more accurately suppressed.

BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing which shows the cross-section along the axial direction of a crankshaft about one Embodiment which actualized the starting rotational force transmission mechanism of the internal combustion engine which concerns on this invention. Sectional drawing which shows the cross-sectional structure centering on an inner race about the embodiment. Sectional drawing which shows the cross-sectional structure along the axial direction of a crankshaft about the starting rotational force transmission mechanism of the conventional internal combustion engine.

Hereinafter, an embodiment in which the present invention is embodied as a starting torque transmission mechanism of an in-vehicle internal combustion engine will be described with reference to FIGS.
FIG. 1 shows a cross-sectional structure of the starting rotational force transmission mechanism along the axial direction of the crankshaft. FIG. 2 shows a cross-sectional structure centering on the inner race.

  As shown in FIGS. 1 and 2, a starting torque transmission mechanism (hereinafter referred to as a transmission mechanism) 1 is fixed to a crankshaft 10 projecting from a cylinder block 5 constituting an engine body EB toward a transmission TM and a starter. 4 is connected to the starter 4 so that the rotational force of 4 can be transmitted.

  Hereinafter, the direction along the axis C1 of the crankshaft 10 is referred to as “axial direction Y”, the left side in FIG. 1 is referred to as “engine body EB side”, and the right side is referred to as “transmission TM side”. Here, a direction orthogonal to the axial direction Y is defined as a “radial direction X”. In the radial direction X, a side toward the axis C1 is defined as “inside”, and a side away from the axis C1 is defined as “outside”.

  The transmission mechanism 1 includes an inner race 20 that is fixed to the crankshaft 10 via bolts 3 </ b> A, and an outer race 30 that is disposed outside the inner race 20 in the radial direction X. A ring gear 70 that meshes with a pinion gear 4a provided on the output shaft of the starter 4 is fixed to the outer side of the outer race 30 in the radial direction X via bolts 3B.

  As shown in FIGS. 1 and 2, a one-way clutch is formed in the annular space formed between the outer circumferential surface 21 of the inner race 20 and the inner circumferential surface 31 of the outer race 30 in the radial direction X in order from the engine body EB side. 40, the ball bearing 50, and the inner seal member 60 are arranged side by side in a line in the axial direction Y.

  The inner seal member 60 includes a main body portion 61, a seal lip portion 62, a dust seal portion 63, and a spring 64. The main body 61 has an annular shape as a whole, has a substantially U-shaped cross section, and is fixed to the inner peripheral surface 31 of the outer race 30 by vulcanization adhesion. The seal lip portion 62 is formed in a portion on the engine body EB side in the axial direction Y on the inner peripheral surface of the main body portion 61 and is slidably in contact with the outer peripheral surface 21 of the inner race 20. The dust seal portion 63 is formed in a portion on the transmission TM side in the axial direction Y on the inner peripheral surface of the main body portion 61 and slidably contacts the outer peripheral surface 21 of the inner race 20. The main body portion 61, the seal lip portion 62, and the dust seal portion 63 are integrally formed of an elastomer. The spring 64 is attached to the main body portion 61 and urges the seal lip portion 62 inward, that is, toward the outer peripheral surface of the inner race 20.

  Between the ball bearing 50 and the inner seal member 60 in the axial direction Y, a C-shaped snap ring 54 for assembling the ball bearing 50 to the inner race 20 and the outer race 30 is provided. The outer periphery of the snap ring 54 is fitted in an annular ring mounting groove 31 d formed on the inner peripheral surface 31 of the outer race 30.

  As shown in FIG. 1, an outer seal member 90 is provided between the outer race 30 and the cylinder block 5 and the oil pan 6 disposed on the engine body EB side of the crankshaft 10 in the radial direction X. It has been.

  The crankshaft 10 includes a main body 11 provided inside the engine main body EB, a flange 12 connected to the transmission TM side of the main body 11 and positioned outside the engine main body EB, and a transmission TM of the flange 12. And a small diameter portion 13 which is connected to the side and forms the end of the crankshaft 10. The flange portion 12 has an annular shape protruding outward from the main body portion 11 and the small diameter portion 13.

  The inner race 20 includes a main body 22, a first protrusion 23 that protrudes from an inner portion in the radial direction X on an end surface of the main body 22 on the transmission TM side, and an engine main body EB of the main body 22. And a second projecting portion 24 projecting from the outer portion in the radial direction X on the side end surface toward the engine body EB side. Each of the main body 22, the first protrusion 23, and the second protrusion 24 has a cylindrical shape.

  As shown in FIG. 2, the main body portion 22 is fitted to the small diameter portion 13 of the crankshaft 10 and is in contact with an end surface (hereinafter referred to as an outer end surface) 12 b of the flange portion 12 on the transmission TM side. That is, the inner peripheral surface 22a of the main body portion 22 faces the outer peripheral surface 13a of the small diameter portion 13, and the end surface (hereinafter referred to as the inner end surface) 22b of the main body portion 22 on the engine main body EB side contacts the outer end surface 12b of the flange portion 12. It touches. Further, an annular protrusion 22d that protrudes outward is provided at the end of the main body 22 on the engine main body EB side. A second protrusion 24 is connected to the protrusion 22d. The flywheel 7 is fitted to the first protrusion 23. The flywheel 7 is fixed to the inner race 20 and the flange portion 12 via bolts 3 </ b> A in a state where the flywheel 7 is in contact with the end face 22 c on the transmission TM side of the main body portion 22. The second protrusion 24 extends outward from the main body 22. The inner peripheral surface 24 a of the second projecting portion 24 faces the outer peripheral surface 12 a of the flange portion 12. In the present embodiment, the bolt 3A, the bolt hole 7e formed in the flywheel 7 through which the bolt 3A is inserted, the bolt hole 22e formed in the inner race 20 through which the bolt 3A is inserted, and the flange portion 12 are formed. Six bolt holes 12e through which the bolts 3A are inserted are provided along the axis C1 of the crankshaft 10 at equal angular intervals (60-degree intervals) in the circumferential direction of the crankshaft 10. A liquid gasket is applied between the inner peripheral surfaces of these bolt holes 7e, 22e, 12e and the bolt 3A. Here, as the liquid gasket, the main component is a silicone compound.

  As shown in FIG. 1, the outer race 30 includes a cylindrical main body portion 32 that surrounds the main body portion 22 and the second projecting portion 24 of the inner race 20, and a central portion in the axial direction Y of the main body portion 32. And an annular ring gear fixing portion 33 extending in the opposite direction. As shown in FIG. 2, the main body 32 includes a first inner protrusion 34 that faces the protrusion 22 d in the radial direction X, and a second inner protrusion 35 that faces the second protrusion 24 in the radial direction X. Is provided.

  The outer diameter of the outer peripheral surface 21 of the inner race 20 is the first outer diameter D1 of the first outer peripheral surface 21a located on the inner periphery of the one-way clutch 40, and the second outer diameter 21b of the second outer peripheral surface 21b located on the inner periphery of the ball bearing 50. The outer diameter D2 and the third outer diameter D3 of the third outer peripheral surface 21c located on the inner periphery of the inner seal member 60 are different from each other. Specifically, the outer diameter of the outer peripheral surface 21 of the inner race 20 decreases in the order of the first outer diameter D1, the second outer diameter D2, and the third outer diameter D3 (D1> D2> D3).

  On the other hand, the inner diameter of the inner peripheral surface 31 of the outer race 30 is the first inner diameter R1 of the first inner peripheral surface 31a located on the outer periphery of the one-way clutch 40 and the second inner peripheral surface 31b located on the outer periphery of the ball bearing 50. The second inner diameter R2 and the third inner diameter R3 of the third inner peripheral surface 31c located on the outer periphery of the inner seal member 60 are different from each other. Specifically, the inner diameter of the inner peripheral surface 31 of the outer race 30 increases in the order of the first inner diameter R1, the second inner diameter R2, and the third inner diameter R3 (R1 <R2 <R3). The first inner peripheral surface 31 a is formed as the inner peripheral surface of the second inner protruding portion 35, and the second inner peripheral surface 31 b is formed as the inner peripheral surface of the first inner protruding portion 34.

  The one-way clutch 40 includes a plurality of sprags 41 and two cages (an inner cage 42a and an outer cage 42b) that hold the sprags 41. Each sprag 41 is sandwiched between the radial direction X between the outer peripheral surface 21 of the inner race 20 and the inner peripheral surface 31 of the outer race 30. A plurality of sprags 41 are provided in the circumferential direction of the crankshaft 10. The inner cage 42a is provided on the inner side in the radial direction X, and the outer cage 42b is provided on the outer side in the radial direction X. Further, the outer cage 42 b is fitted in a cage mounting groove 31 e formed on the first inner peripheral surface 31 a of the outer race 30. The one-way clutch 40 allows a rotational force in one direction to be transmitted from the outer race 30 to the inner race 20, but prevents a reverse rotational force from being transmitted.

  The ball bearing 50 is disposed between the inner ring 51 that is press-fitted and fixed to the second outer peripheral surface 21 b of the inner race 20, the outer ring 52 that is inserted into the second inner peripheral surface 31 b of the outer race 30, and the inner ring 51 and the outer ring 52. And a plurality of balls 53 held by a held cage (not shown). The balls 53 are rolling elements that can roll by sliding on the inner ring 51 and the outer ring 52, respectively. The ball bearing 50 allows the outer race 30 to rotate relative to the inner race 20.

  According to the transmission mechanism 1 having the above configuration, the rotational force of the starter 4 is transmitted from the ring gear 70 and the outer race 30 to the inner race 20 and the crankshaft 10 via the one-way clutch 40. On the other hand, when the crankshaft 10 is rotated by the engine operation and the rotational speed of the crankshaft 10 becomes higher than the rotational speed of the ring gear 70, the one-way clutch 40 is released. Thereby, the rotational force of the inner race 20 is not transmitted to the outer race 30. Further, the rotation of the ring gear 70 is stopped by stopping the operation of the starter 4 along with this.

  Incidentally, as described above, in such a starting torque transmission mechanism of an internal combustion engine, the outer race surface 12a of the flange portion 12 and the inner surface facing the outer race surface 12a are provided for the purpose of improving the assembly of the inner race 20 to the crankshaft 10. It is conceivable to form a gap over the entire circumference with the inner peripheral surface 24a of the race 20. Here, as described above, the outer end surface 12b of the flange portion 12 and the inner end surface 22b of the inner race 20 facing the flange portion 12 are pressed against each other by the axial force of the bolt 3A. Since there is a gap between the inner end faces 22b, there is a concern that oil leaks outside through the gap.

  Therefore, in the present embodiment, the outer peripheral surface 12a of the flange portion 12 has a spiral groove shape along the outer peripheral surface 12a, and the inner peripheral surface 24a of the inner race 20 facing the outer peripheral surface 12a. And an engaging portion for suppressing the passage of oil by engaging the groove of the outer peripheral surface 12a and the groove of the inner peripheral surface 24a with each other. The structure to be formed is adopted. That is, the outer peripheral surface 12a of the flange portion 12 is a male screw, and the inner peripheral surface 24a of the inner race 20 is a female screw. Specifically, the grooves on the outer peripheral surface 12a of the flange portion 12 and the grooves on the inner peripheral surface 24a of the inner race 20 are formed in such a manner that the fastening force of these grooves increases as the crankshaft 10 rotates. Further, a liquid gasket is applied to the engaging portion between the groove on the outer peripheral surface 12 a of the flange portion 12 and the groove on the inner peripheral surface 24 a of the inner race 20. Here, as the liquid gasket, the main component is a silicone compound. Thereby, oil is prevented from leaking to the outside through between the flange portion 12 and the inner race 20.

  By the way, in such a starting torque transmission mechanism of an internal combustion engine, in order to supply oil from the outside to the oil chamber via the one-way clutch and the ball bearing, a sufficient amount of oil is supplied to the one-way clutch and the ball bearing. It is necessary to supply oil. In this case, however, an excessive amount of oil is supplied to the one-way clutch or ball bearing, and the oil is agitated as the one-way clutch or ball bearing rotates, resulting in an increase in rotational resistance. It becomes.

  In addition, in such a starting torque transmission mechanism, the oil once flowing into the one-way clutch, the ball bearing and the oil chamber has a tendency to stay difficult to be discharged from them, so that the retained oil contains a lot of sludge. It will be in a state of including. As a result, the lubrication performance of the oil is reduced, poor lubrication of the one-way clutch, the ball bearing and the inner seal member occurs, and the oil in the oil chamber stays and the temperature rises, so that the cooling efficiency of the inner seal member is lowered. This causes various inconveniences.

  Therefore, in the present embodiment, the inner race 20 is formed with a supply passage 80 that opens to the end surface 24b on the side close to the engine body EB of the inner race 20 and supplies oil to the oil chamber S. Yes. The oil is jetted and supplied to the supply passage 80 from the oil jet mechanism OJ. Here, the supply passage 80 includes a first passage 81 extending from the opening 81a formed in the end surface 24b of the inner race 20 toward the transmission TM in the axial direction Y, and a second outer peripheral surface 21b of the inner race 20 partially. The second passage 82 is connected to the first passage 81 and is formed in a shape recessed inward. A plurality of such supply passages 80 are formed in the circumferential direction of the crankshaft 10. Accordingly, oil can be supplied to the oil chamber S without supplying excessive oil to the one-way clutch 40 and the ball bearing 50, and an increase in rotational resistance of the one-way clutch 40 and the ball bearing 50 is suppressed. I have to. Further, poor lubrication of the one-way clutch 40, the ball bearing 50, and the inner seal member 60 and a decrease in cooling efficiency of the inner seal member 60 are suppressed.

According to the starting rotational force transmission mechanism of the internal combustion engine according to the present embodiment described above, the following operational effects can be obtained.
(1) In the present embodiment, the outer peripheral surface 12a of the flange portion 12 has a spiral groove shape along the outer peripheral surface 12a, and the inner peripheral surface of the inner race 20 facing the outer peripheral surface 12a. 24a has a spiral groove shape along the inner peripheral surface 24a, and the grooves on the outer peripheral surface 12a and the grooves on the inner peripheral surface 24a engage with each other to suppress the passage of oil. The structure in which is formed is adopted. According to such a configuration, unlike the configuration in which a gap is formed over the entire circumference between the outer peripheral surface 12a of the flange portion 12 and the inner peripheral surface 24a of the inner race 20 opposed thereto, the outer peripheral surface 12a of the flange portion 12 An engaging portion between the groove on the outer peripheral surface 12a and the groove on the inner peripheral surface 24a serves as a barrier for the oil that is about to pass between the inner peripheral surface 24a of the inner race 20 and the opposing inner race 20. For this reason, infiltration of oil between the outer end surface 12b of the flange portion 12 and the inner end surface 22b of the inner race 20 is suppressed. In addition, the inner race 20 can be assembled to the flange portion 12 by rotating the inner race 20 with respect to the flange portion 12 to engage the groove of the outer peripheral surface 12a and the groove of the inner peripheral surface 24a. Therefore, the engaging portion can be realized without impairing the assembling property of the inner race 20 with respect to the crankshaft 10. Incidentally, by adopting a bolt having greater strength as a bolt for connecting the flange portion 12 and the inner race 20, or by increasing the number of bolts, the surface pressure between the outer end surface 12b and the inner end surface 22b can be reduced. It is conceivable that the gap between the end faces 12b, 22b is reduced by suppressing the leakage of oil to the outside. However, according to the above configuration, oil can be prevented from leaking outside through the gap between the flange portion 12 and the inner race 20 without changing the configuration of the bolt.

  (2) In the present embodiment, the inner race 20 is formed with a supply passage 80 that opens to the end surface 24b of the inner race 20 on the side close to the engine body EB and supplies oil to the oil chamber S. The configuration is adopted. According to such a configuration, oil is supplied to the oil chamber through the supply passage formed in the inner race. For this reason, oil can be supplied to the oil chamber without supplying excessive oil to the one-way clutch and the bearing, and an increase in rotational resistance of the one-way clutch and the bearing can be suppressed. Further, poor lubrication of the one-way clutch, the bearing and the seal member, and a decrease in cooling efficiency of the seal member can be suppressed.

  (3) In the present embodiment, the grooves on the outer peripheral surface 12a of the flange portion 12 and the grooves on the inner peripheral surface 24a of the inner race 20 are formed in such a manner that the fastening force of these grooves increases as the crankshaft 10 rotates. Is adopted. According to such a configuration, the fastening force between the groove on the outer peripheral surface 12a and the groove on the inner peripheral surface 24a increases with the rotation of the crankshaft 10, so that the grooves on the outer peripheral surface 12a and the inner peripheral surface 24a are increased with engine operation. It can suppress that the fastening force with a groove | channel reduces and the space between these grooves increases. Therefore, oil can be accurately suppressed from passing between the groove on the outer peripheral surface 12a and the groove on the inner peripheral surface 24a.

  (4) In this embodiment, a configuration in which a liquid gasket is further applied to the engaging portion between the groove on the outer peripheral surface 12a of the flange portion 12 and the groove on the inner peripheral surface 24a of the inner race 20 is employed. According to such a configuration, since the space between the groove on the outer peripheral surface 12a and the groove on the inner peripheral surface 24a is filled with the liquid gasket, the space between the groove on the outer peripheral surface 12a and the groove on the inner peripheral surface 24a is between. It is possible to accurately suppress the passage of oil.

  The starting rotational force transmission mechanism of the internal combustion engine according to the present invention is not limited to the configuration exemplified in the above embodiment, and can be implemented as, for example, the following form appropriately modified.

  In the above embodiment, the liquid gasket mainly composed of a silicone-based compound is exemplified, but the liquid gasket is not limited to this, and the groove of the outer peripheral surface 12a of the flange portion 12 and the inner peripheral surface of the inner race 20 As long as it fills the space between the grooves 24a, the main component may be a compound other than silicone.

  As described in the above embodiment, the liquid gasket is applied to the engaging portion between the groove of the outer peripheral surface 12a of the flange portion 12 and the groove of the inner peripheral surface 24a of the inner race 20, and the groove of the outer peripheral surface 12a. And the space between the inner peripheral surface 24a and the groove of the inner peripheral surface 24a are desirable for accurately suppressing the passage of oil. However, the present invention is not limited to this, and the passage of oil can be accurately suppressed only through the engaging portion formed by engaging the groove of the outer peripheral surface 12a and the groove of the inner peripheral surface 24a with each other. In addition, the application of the liquid gasket can be omitted.

  As described in the above embodiment, the outer groove portion that is the groove of the outer peripheral surface 12a of the flange portion 12 and the inner groove portion that is the groove of the inner peripheral surface 24a of the inner race 20 are connected to the outer groove portion as the crankshaft 10 rotates. It is desirable to form in such a manner that the fastening force between the inner groove portion and the inner groove portion is increased in order to suppress the passage of oil accurately while maintaining the fastening force between the outer groove portion and the inner groove portion in a large state. However, since the flange portion 12 of the crankshaft 10 and the inner race 20 are fastened by the bolt 3A, the space between the outer groove portion and the inner groove portion does not increase excessively. Therefore, if it does not matter that oil passes through the space between the outer groove portion and the inner groove portion in the state where the fastening force between the outer groove portion and the inner groove portion is the lowest, the direction of the spiral of the outer groove portion and the inner The direction of the spiral of the groove portion can be set so that the fastening force between the outer groove portion and the inner groove portion decreases as the crankshaft rotates.

  In the above embodiment, the groove formed on the outer peripheral surface 12a of the flange portion 12 (outer groove portion) and the groove formed on the inner peripheral surface 24a of the inner race 20 opposite to the groove (inner groove portion) are respectively provided. A spiral shape is formed, and the outer groove portion and the inner groove portion are engaged with each other to form an engaging portion. However, the engaging portion according to the present invention is not limited to this, and for example, a slit-like groove extending along the axial direction Y on the outer peripheral surface of the flange portion and the inner peripheral surface of the inner race facing the flange portion. In addition, the engaging portion may be formed by engaging the groove on the outer peripheral surface and the groove on the inner peripheral surface with each other.

  As in the above-described embodiment, the inner race 20 may be formed with the supply passage 80 that opens to the end surface 24b of the inner race 20 on the side close to the engine body EB and supplies oil to the oil chamber S. It is desirable to suppress an increase in rotational resistance of the one-way clutch 40 and the ball bearing 50 (bearing), poor lubrication of the one-way clutch 40, the ball bearing 50, and the inner seal member 60, and a decrease in cooling efficiency of the inner seal member 60. . However, the present invention is not limited to the one provided with such a supply passage, and one without such a supply passage can also be adopted.

  DESCRIPTION OF SYMBOLS 1 ... Starting torque transmission mechanism, 3A, 3B ... Bolt, 4 ... Starter, 4a ... Pinion gear, 5 ... Cylinder block, 6 ... Oil pan, 7 ... Flywheel, 7e ... Bolt hole, 10 ... Crankshaft (engine output) Axis), 11 ... Main body, 12 ... Flange, 12a ... Outer peripheral surface, 12b ... Outer end surface, 12e ... Bolt hole, 13 ... Small diameter part, 13a ... Outer peripheral surface, 20 ... Inner race, 21 ... Outer peripheral surface, 21a ... 1st outer peripheral surface, 21b ... 2nd outer peripheral surface, 21c ... 3rd outer peripheral surface, 22 ... Main body part, 22a ... Inner peripheral surface, 22b ... Inner end surface, 22c ... End surface, 22d ... Projection part, 22e ... Bolt hole, 23 ... 1st protrusion part, 24 ... 2nd protrusion part, 24a ... Inner peripheral surface, 24b ... End surface, 30 ... Outer race, 31 ... Inner peripheral surface, 31a ... First inner peripheral surface, 31b ... Second inner peripheral surface, 31c ... 3rd inner peripheral surface, 31d ... Mounting groove, 31e ... fitting groove, 32 ... main body part, 33 ... ring gear fixing part, 34 ... first inner protruding part, 35 ... second inner protruding part, 40 ... one-way clutch, 41 ... sprag, 42a ... inner Cage, 42b ... outer cage, 50 ... ball bearing (bearing), 51 ... inner ring, 52 ... outer ring, 53 ... ball, 54 ... snap ring, 60 ... inner seal member (seal member), 61 ... main body, 62 ... seal Lip part, 63 ... dust seal part, 64 ... spring, 70 ... ring gear, 80 ... supply passage, 81 ... first passage, 82 ... second passage, 90 ... outer seal member, EB ... engine body, TM ... transmission, S ... Oil chamber.

Claims (5)

The flange includes an inner peripheral surface facing an outer peripheral surface of a flange portion provided at one end of the engine output shaft, and an inner end surface facing an outer end surface which is an end surface on the side away from the engine main body in the flange portion. A cylindrical inner race connected to the portion by a connecting shaft;
An outer race that is provided on the outer periphery of the inner race to transmit the rotational force of the starter;
A bearing that is provided in an annular space formed by an inner peripheral surface of the outer race and an outer peripheral surface of the inner race and supports the outer race so as to be relatively rotatable with respect to the inner race;
A one-way clutch that is arranged in parallel with the bearing in the annular space and allows transmission of rotational force from the outer race to the inner race;
A starting rotational force transmission mechanism for an internal combustion engine, comprising: a seal member that defines an oil chamber in a part of the annular space that is further away from the engine body than the bearing and the one-way clutch;
The starting rotation of the internal combustion engine, wherein the outer peripheral surface of the flange portion and the inner peripheral surface of the inner race opposite to the flange portion are formed with engaging portions that engage with each other to suppress the passage of oil. Force transmission mechanism. The starting rotational force transmission mechanism for an internal combustion engine according to claim 1,
The inner race is provided with a supply passage for opening the end surface of the inner race close to the engine body and supplying oil to the oil chamber. mechanism. In the starting rotational force transmission mechanism of the internal combustion engine according to claim 1 or 2,
The engaging portion is formed on the outer peripheral surface of the flange portion and is formed on the outer peripheral groove portion having a spiral shape along the outer peripheral surface, and on the inner peripheral surface of the inner race and along the inner peripheral surface. A starting torque transmission mechanism for an internal combustion engine, comprising: an inner groove portion that engages with the outer groove portion in a spiral shape. The starting rotational force transmission mechanism for an internal combustion engine according to claim 3,
The starting rotational force transmission mechanism for an internal combustion engine, wherein the outer groove portion and the inner groove portion are formed in such a manner that a fastening force between the outer groove portion and the inner groove portion increases as the engine output shaft rotates. In the starting rotational force transmission mechanism of the internal combustion engine according to claim 1 or 4,
A starting torque transmission mechanism for an internal combustion engine, wherein a liquid gasket is further applied to the engaging portion.

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