JP6376039B2 - Power transmission device - Google Patents

Description

  The present invention relates to a power transmission device that transmits engine power, and in particular, transmits torque in a first rotational direction so that torque is not transmitted in a second rotational direction opposite to the first rotational direction. The present invention relates to a power transmission device including a configured one-way clutch.

  An example of this type of device is described in Patent Document 1. In this apparatus, a one-way clutch (hereinafter referred to as OWC) is disposed between an output shaft of an engine and an input shaft of a transmission. The OWC has an outer ring fixed to the transmission case and an inner ring connected to the output shaft via a flywheel. In the OWC, the outer ring and the inner ring rotate relative to each other when the engine rotates in the forward direction, and the outer ring and the inner ring are integrated when the engine tries to rotate in the opposite direction opposite to the forward direction. It is configured.

  Patent Document 2 describes a clutch housing in which a drain hole is formed. The clutch housing includes an upper end plate and a lower end plate that close the opening. A drain hole is formed at the lower end of the lower end plate, and a protrusion for guiding water that has entered the clutch housing to the drain hole is formed on the side surface of the lower end plate on the clutch housing side.

  Moreover, the apparatus described in Patent Document 3 includes a clutch chamber that houses a dry clutch in a clutch housing. An intake hole is formed on the outer side in the radial direction of the housing cover that closes the opening of the clutch housing, and an exhaust hole is formed on the inner side in the radial direction. When a pressure difference is generated in the clutch chamber due to the centrifugal force accompanying the rotation of the dry clutch, air is sucked into the clutch chamber from the intake hole due to the pressure difference. The air is discharged together with dust through the gap of the clutch drum from the exhaust hole to the space between the end of the engine block and the housing cover.

  Furthermore, in the hybrid vehicle described in Patent Document 4, an OWC and a brake are arranged between the engine and the transmission. Those OWCs and brakes are configured to be free when the engine rotates in the forward direction, and locked when the engine attempts to rotate in the opposite direction opposite to the forward direction.

International Publication No. 2013/140527 Japanese Utility Model Publication No. 58-130132 JP 2014-062556 A JP 2000-355224 A

  In the configuration described in Patent Document 1, the internal space of the case is divided into an engine side space and a transmission side space by the OWC and the flywheel, and each space is closed by the OWC and the flywheel. For this reason, when foreign matter enters the spaces through the gaps of the case, it may be difficult to discharge the foreign matter. In the case, for example, the inner pressure decreases in the radial direction due to the centrifugal force accompanying the rotation of the flywheel, and the outer pressure increases. This pressure difference causes an air flow in the radial direction. The foreign matter moves in each space on this air flow. And there is a possibility that the sliding portion will wear out by entering the sliding portion of the OWC.

  The drain hole described in Patent Document 2 is for discharging water accumulated in the clutch housing, and enters the spaces and discharges foreign matter moving by the air flow to the outside of the case. It is not a thing. Moreover, in the structure described in patent document 3, the foreign material in a clutch chamber is discharged | emitted by the air flow to the space between the edge part of an engine block and a housing cover. Therefore, if the output shaft of the engine described in Patent Document 3 is fixed by the OWC described in Patent Document 1, foreign matter discharged from the clutch chamber is supplied to the OWC, and the sliding portion of the OWC There is a possibility that foreign matter may enter and wear. Such inconvenience may occur in the same manner when the brake described in Patent Document 4 is provided instead of OWC.

  The present invention has been made paying attention to the above technical problem, and an object of the present invention is to provide a power transmission device that can suppress the intrusion of foreign matter into the lock mechanism.

In order to achieve the above object, the present invention is configured to rotate the output shaft of the engine only in one direction between the engine and the transmission mechanism and prevent rotation in a direction opposite to the one direction. The locking mechanism includes a fixed member and a movable member, the movable member is coupled to the output shaft, and the fixed member is disposed between a housing of the transmission mechanism and an engine block of the engine. In the power transmission device in which a space formed by the housing and the engine block is divided into an engine side space and a transmission mechanism side space by the lock mechanism , the output is provided on the housing side of the engine block. the multiple ribs extending radially provided from the axis, next to one another on the lower side of a lower part and the engine block of the fixing member A first through hole that communicates the engine-side space and the transmission mechanism-side space is formed at a position corresponding to the ribs, and is disengaged from the ribs in the axial direction of the output shaft; A second through hole that communicates the inside and the outside of the transmission mechanism side space is formed in a lower portion of the housing, and the second through hole is displaced from a region where the lock mechanism is disposed in the axial direction. And it is located below the first through hole .

  According to this invention, the first through hole is formed at a position corresponding to the lower portion of the fixing member of the lock mechanism and between the ribs provided adjacent to each other on the lower side of the engine block. . The second through hole is formed in a lower portion of the housing and at a position deviated in the axial direction of the engine output shaft from between the ribs provided adjacent to each other. Therefore, foreign matter that has entered the engine-side space through the gap in the housing is discharged from the inside of the power transmission device to the outside through each through hole. Specifically, a part of the air in the engine side space flows along the rib. The foreign matter rides on the air flow and reaches the transmission mechanism side space through the first through hole. Next, the foreign matter moves along the radial air flow in the transmission mechanism side space, and passes through the second through hole and is discharged to the outside of the housing. As a result, the foreign matter can be prevented from entering the sliding portion of the lock mechanism. Thereby, wear of the lock mechanism due to foreign matter can be suppressed. As a result, durability and reliability of the power transmission device can be improved.

It is sectional drawing which shows a part of power transmission device which concerns on this embodiment. It is a figure which shows an example of the fixing member in this embodiment, (a) of FIG. 2 shows the front view of a fixing member, (b) of FIG. 2 is a figure which expands and shows a part of fixing member. It is a figure which shows an example of the electrodeposition coating in this embodiment. It is a figure which shows distribution of the coating material which accumulates on the outer periphery of a fixed plate when a fixed plate is pulled up from a coating material. It is an arrow line view which follows the VV line shown in FIG. It is an arrow line view which follows the VI-VI line shown in FIG. It is a figure which shows an example of the vehicle carrying the power transmission device which concerns on this embodiment.

  FIG. 7 is a view showing an example of a vehicle on which the power transmission device according to this embodiment is mounted. The vehicle shown here is, for example, a hybrid vehicle provided with an engine 1, a first motor (MG1) 2 and a second motor (MG2) 3 as driving force sources, and the power split mechanism 4 Thus, the first motor 2 side and the drive shaft 5 side are divided and transmitted. Further, the second motor 3 is driven by the electric power generated by the first motor 2, and the power output from the second motor 3 can be applied to the drive shaft 5. The power split mechanism 4, the first motor 2, the second motor 3 and the like described above correspond to the transmission mechanism in this embodiment.

  The power split mechanism 4 is disposed on the same axis as the output shaft 1a of the engine 1, and in the example shown in FIG. 7, is constituted by a single pinion type planetary gear mechanism. The power split mechanism 4 includes a sun gear 6 that is an external gear, a ring gear 7 that is an internal gear arranged concentrically with the sun gear 6, and a pinion gear that meshes with the sun gear 6 and the ring gear 7. It has a carrier 8 that holds it so that it can rotate and revolve. The first motor 2 is connected to the sun gear 6. The first motor 2 is disposed adjacent to the power split mechanism 4 on the side opposite to the engine 1. The ring gear 7 is an output element, and an output gear 9 is attached to the ring gear 7 as an output member. The output gear 9 is connected to a differential 10 that transmits torque to the drive shaft 5. The second motor 3 is connected to a power transmission path from the output gear 9 to the differential 10. An input shaft 4 a of the power split mechanism 4 is connected to the carrier 8. The output shaft 1a of the engine 1 is connected to the input shaft 4a via a damper mechanism 11, a torque limiter mechanism 12, a flywheel 13, and a one-way clutch (hereinafter referred to as OWC) 14.

  The damper mechanism 11 is for reducing torque fluctuation of the output shaft 1a and torsional vibration due to torque fluctuation, and is configured in the same manner as conventionally known. The damper mechanism 11 will be described briefly. The damper mechanism 11 includes a driving side plate that rotates integrally with the output side member of the torque limiter mechanism 12, a driving side plate that is disposed opposite to the driving side plate, and A driven side plate capable of relative rotation, and a spring disposed in a window hole portion formed in these plates and compressed by relative rotation of each plate are provided. The driven plate of the damper mechanism 11 described above is coupled to the input shaft 4a of the power split mechanism 4 by, for example, a spline. The torque limiter mechanism 12 has the same configuration as that conventionally known, and is configured to generate a slip and cut off torque transmission when a torque exceeding a preset transmission torque capacity is input. . A fixed plate 16 of the OWC 14 is disposed between the engine block 1b and the housing 15 that houses the power split mechanism 4 and the like. The housing 15 and the engine block 1b are bolted with the fixing plate 16 sandwiched therebetween.

  The OWC 14 is disposed on the same rotational axis as the output shaft 1a of the engine 1, and includes two rotational members that can rotate relative to each other, that is, an inner ring 14a and an outer ring 14b, and the inner ring 14a and the outer ring 14b are disposed concentrically. Has been. The inner ring 14a and the fixed plate 16 are coupled by a spline 19 as will be described later. The outer ring 14b is fixed to the output shaft 1a together with the flywheel 13. An engagement mechanism (not shown) is held on the outer ring 14b. The engagement mechanism allows relative rotation between the inner ring 14a and the outer ring 14b when a torque in the forward rotation direction acts on the outer ring 14b, and allows the inner ring 14a and the outer ring 14b to move when a torque in the reverse rotation direction acts on the outer ring 14b. Are configured to be integrated. Therefore, the OWC 14 transmits torque between the output shaft 1a and the input shaft 4a when the output shaft 1a rotates in the forward direction, and rotates the output shaft 1a when torque in the reverse rotation direction acts on the output shaft 1a. It is configured to stop. The normal rotation is rotation in the rotation direction of the engine 1 during the combustion operation, and the reverse rotation is rotation in the direction opposite to the normal rotation. The OWC 14 described above corresponds to the lock mechanism in this embodiment, the outer ring 14b corresponds to the movable member in this embodiment, and the above-described fixed plate 16 corresponds to the fixed member in this embodiment.

  FIG. 1 is a cross-sectional view showing a part of the power transmission device according to this embodiment. The flywheel 13 is fixed to the output shaft 1 a of the engine 1 by the first bolt 17. The torque limiter mechanism 12 is attached to the outer portion of the flywheel 13 by the second bolt 18. The damper mechanism 11 is connected to the output side of the torque limiter mechanism 12.

  A fixed plate 16 is fixed between the engine block 1 b and the housing 15. 2 is a view showing an example of the fixing plate 16 of the OWC 14. FIG. 2A is a front view of the fixing plate 16, and FIG. 2B is an enlarged view of a part of the fixing plate 16. As shown in FIG. FIG. As shown in FIG. 2A, the fixing plate 16 is a substantially circular member, and a flange portion 16a formed on the outer peripheral portion thereof is sandwiched between the engine block 1b and the housing 15, and is illustrated. It is fixed to the engine block 1b together with the housing 15 by bolts that are not used. On the other hand, a cylindrical portion 16c extending in the left-right direction in FIG. 1, that is, the rotation axis direction is formed on the inner peripheral portion 16b of the fixed plate 16, and spline teeth 19a are formed on the outer peripheral surface of the cylindrical portion 16c. Spline grooves 19b that fit into the spline teeth 19a are formed in the inner ring 14a of the OWC 14 described above. The outer ring 14b of the OWC 14 is fixed to the output shaft 1a together with the flywheel 13 by the first bolt 17 described above.

  Further, as shown in FIG. 2A, knock holes 16d and bolt holes 16e are formed in the flange portion 16a. In the example shown here, two knock holes 16d are formed and nine bolt holes 16e are formed. These knock holes 16d are referred to as a first knock hole 16d1 and a second knock hole 16d2 in the following description. By inserting knock pins (not shown) attached to the engine block 1b into the knock holes 16d1 and 16d2, the fixing plate 16 is positioned and temporarily fixed with respect to the engine block 1b. Further, the housing 15 is pressed against the flange portion 16a of the fixing plate 16 temporarily fixed to the engine block 1b in this manner, and is sandwiched between the housing 15 and the engine block 1b. Then, bolts (not shown) are inserted into the respective bolt holes 16e, and the fixing plate 16 is fixed to the housing 15 and the engine block 1b.

  A liquid reservoir portion 16f is formed outside the first knock hole 16d1 in the radial direction of the fixed plate 16. The liquid reservoir 16f is a place where the paint flowing on the surface of the fixed plate 16 gathers when the suspended fixed plate 16 is pulled up from the paint as described later. Therefore, as shown to (a) of FIG. 2, it protrudes and protrudes in the radial direction from the outer periphery of the periphery. The liquid reservoir 16f is shown as a hatched area in FIG.

  Further, the inner portion 16b of the fixed plate 16 described above is offset to the engine 1 side with respect to the flange portion 16a in the rotational axis direction, and a bent portion 16g is formed between the flange portion 16a and the inner peripheral portion 16b. It has become. As shown in FIG. 2A, a first through hole 20 that penetrates the fixing plate 16 in the thickness direction through a bent portion 16g opposite to the first knock hole 16d1 across the axis of the fixing plate 16. Is formed. The first through hole 20 is located below the engine block 1b in the vertical direction of the vehicle when the fixing plate 16 is attached to the engine block 1b. Further, the fixing plate 16 is formed at a position corresponding to between ribs 26a and 26b adjacent to each other, which will be described later, provided below the engine block 1b. In FIG. 2A, portions corresponding to the ribs 26a and 26b in the fixed plate 16 are described as regions surrounded by dotted lines. Moreover, the outer peripheral inner peripheral surface 20a in the radial direction of the fixed plate 16 among the inner peripheral surfaces of the first through holes 20 is formed in an arc shape, for example. The engine side space SE and the transmission mechanism side space ST communicate with each other through the first through hole 20. In addition, the 1st through-hole 20 can be formed by press work as an example. The first through hole 20 corresponds to the first through hole in this embodiment.

  The fixed plate 16 is provided with a predetermined coating to prevent corrosion. The coating is, for example, cationic electrodeposition coating. In this cationic electrodeposition coating, the fixed plate 16 that is the object to be coated is suspended by a hanger or hook that functions as an electrode and immersed in the cationic electrodeposition coating. . FIG. 3 is a diagram showing an example of electrodeposition coating in this embodiment. As shown in FIG. 3, a hanger or a hook made of a conductive material is inserted as the cathode 21 into the first through hole 20 in the fixed plate 16. The cathode 21 is formed, for example, in an L shape, and the inner peripheral surface 20a is brought into contact with the flange portion 21a of the cathode 21 extending in the left-right direction in FIG. By doing so, the inner peripheral surface 20a is pressed against the ridgeline of the flange portion 21a by a load corresponding to the mass of the fixed plate 16. The cathode 21 corresponds to the hanging member in this embodiment.

  Further, when a apparent force is generated at the contact portion between the flange portion 21a and the inner peripheral surface 20a and the electrode is moved along the inner peripheral surface 20a, the fixing plate 16 is suspended by the component force. In the vertical direction in the state, the flange portion 21a moves to the uppermost side of the inner peripheral surface 20a. Finally, the flange portion 21a comes into contact with the uppermost inner peripheral surface 20a in a state where the fixed plate 16 is suspended. This contact position is a so-called suspension position. Further, since the inner peripheral surface 20a comes into contact with the ridge line of the flange portion 21a, the ridge line and the axis of the fixing plate 16 are maintained in a substantially parallel state, and the contact portion between the flange portion 21a and the inner peripheral surface 20a is almost the same. It becomes constant and the hanging posture of the fixed plate 16 is stabilized. In this state, the flange portion 21a and the fixing plate 16 are immersed in the cationic electrodeposition paint together with the anode 22, and thereafter, electricity is passed between these electrodes 21 and 22. In this way, electrodeposition coating is performed on the fixed plate 16. Then, after the fixed plate 16 is pulled out of the paint and baked, the fixed plate 16 is removed from the cathode 21. Thereafter, as described above, the engine block 1b is attached. In addition, since the said contact part is substantially constant, the film is not formed in the said contact part, or the film is thinner compared with another location.

  FIG. 4 is a diagram showing the distribution of the paint accumulated on the outer peripheral edge of the fixed plate 16 when the fixed plate 16 is pulled up from the paint, and is a diagram in which the top and bottom of FIG. 2 are reversed. Since the area of the fixing plate 16 corresponding to the regions A and B is small at the outer peripheral edges on both ends of the fixing plate 16 indicated by reference characters A and B in FIG. 4, the fixings corresponding to the regions A and B are fixed. The amount of paint flowing downward along the surface of the plate 16 in the vertical direction in FIG. 4 is small. Therefore, there is little paint accumulated on the outer peripheral edge corresponding to each of the areas A and B. Therefore, even if the fixed plate 16 pulled up from the paint is baked as it is, the thickness of the coating hardly increases at the outer peripheral edge thereof. 4, the area of the fixing plate 16 corresponding to the region C is larger than the areas corresponding to the region A and the region B. Therefore, the amount of paint flowing downward along the surface of the fixed plate 16 is larger than in the areas A and B. However, the outer peripheral edge, that is, the contour line on the lower side of the fixed plate 16 corresponding to the region C is gently inclined as shown in FIG. Therefore, the paint is dispersed over the entire outer peripheral edge of the fixed plate 16 corresponding to the region C. As a result, like the regions A and B, the thickness of the coating at the outer peripheral edge corresponding to the region C is difficult to increase.

Further, in the upper part of the cylindrical part 16c in the vertical direction in FIG. 4 indicated by reference numeral D in FIG. Few. Further, the coating material flowing to the upper portion of the cylindrical portion 16c flows downward in the vertical direction in FIG. 4 along the outer peripheral surface of the cylindrical portion 16c. For this reason, there is little paint accumulated in the region D, and the thickness of the coating on the upper portion of the cylindrical portion 16c is unlikely to increase, as in the regions A, B, and C. On the other hand, the region indicated by the symbol E in FIG. 4, that is, the liquid reservoir 16f is located on the lower side in the vertical direction in FIG. 4, and the inclination of the contour line corresponding to the liquid reservoir 16f is other than Greater than part. Therefore, the paint that has flowed from the areas A, B, C, and D along the outer peripheral edge of the fixed plate 16 gathers in the area E. Even by this, it is possible to prevent the thickness of the coating in those places with paint accumulated in a portion other than the liquid reservoir 16f is increased.

  As shown in FIG. 1, a space S formed by the housing 15 and the engine block 1b is divided into an engine side space SE and a transmission mechanism side space ST by the OWC 14 and the fixed plate 16 configured as described above. Further, the engine block 1 b has a gap 23, and the gap 23 is closed by a cover 24. A second through hole 25 for discharging foreign matter such as water and dust that has entered the housing 15 to the outside is formed in the lower part of the housing 15 in the vertical direction of the vehicle so as to penetrate the housing 15 in the plate thickness direction. In addition, the second through hole 25 is formed so as to be shifted with respect to the region α where the OWC 14 is disposed in the housing 15 in the rotational axis direction of the power transmission device according to this embodiment. Further, the housing 15 is formed at a position corresponding to a space between adjacent ribs 26a and 26b described later. The second through hole 25 described above corresponds to the second through hole in this embodiment.

  FIG. 5 is an arrow view along the line VV shown in FIG. A plurality of reinforcing ribs 26 extend radially from the output shaft 1a of the engine 1 in the engine block 1b. The first through hole 20 described above is formed between the ribs 26a, 26b adjacent to each other below the output shaft 1a in the fixed plate 16 with the fixed plate 16 attached to the engine block 1b. . FIG. 6 is an arrow view along the VI-VI line shown in FIG. In FIG. 6, portions corresponding to the ribs 26a and 26b are shown as regions surrounded by dotted lines. Further, as shown in FIG. 6, a second through hole 25 is formed at a position corresponding to the lower portion of the housing 15 and between the ribs 26 a and 26 b.

  Next, the operation of the power transmission device having the above configuration will be described. When the engine 1 is outputting power, the flywheel 13 and the outer ring 14b of the OWC 14 rotate with the rotation of the output shaft 1a. An air flow from the inside toward the outside in the radial direction is generated in the engine side space SE by the centrifugal force accompanying the rotation of the flywheel 13 and the outer ring 14b. The air flow flows along the ribs 26 and moves to the transmission mechanism side space ST through the first through holes 20. Further, the foreign matter in the engine side space SE moves on the air flow to the transmission mechanism side space ST. As a result, the foreign matter in the engine side space SE moves to the transmission mechanism side space ST without passing through the OWC 14.

  Further, in the transmission mechanism side space ST, an air flow is generated in the radial direction from the inside to the outside in the same manner as described above, and the foreign matter moves on the air flow. Then, it is discharged together with air from the second through hole 25 to the outside of the housing 15. The foreign matter that has directly entered the transmission mechanism side space ST is discharged along with the air from the second through hole 25 to the outside of the housing 15 by riding on the air flow in the transmission mechanism side space ST. Further, as described above, since the second through hole 25 is not formed in the region α where the OWC 14 is disposed, the foreign matter passes from the outside of the housing 15 to the inside of the housing 15 through the second through hole 25. Even if it enters, it can be avoided that the foreign matter adheres to the OWC 14.

  Therefore, in the power transmission device having the above configuration, the foreign matter that has entered the engine-side space SE moves on the radial air flow, and is discharged to the outside of the housing 15 through the through holes 20 and 25. As a result, foreign matter can be prevented from entering the sliding portion between the inner ring 14a and the outer ring 14b of the OWC 14. Accordingly, it is possible to suppress the occurrence of an abnormality such that the OWC 14 is worn out due to the foreign matter or rust is generated to hinder its operation. As a result, durability and reliability of the OWC 14 and the power transmission device can be improved.

  Moreover, since the fixing plate 16 is suspended using the first through-hole 20, the number of processing steps performed on the fixing plate 16 can be reduced, and the processing cost can be reduced correspondingly. Moreover, since the attitude | position of the stationary plate 16 in a coating device is stabilized, it can suppress that the conduction | electrical_connection state of the stationary plate 16 changes. Therefore, the electrodeposition coating can be uniformly applied to the entire fixing plate 16. When the fixed plate 16 is pulled up from the paint, the paint flowing on the surface of the fixed plate 16 collects in the liquid reservoir 16f. Also by this, the film thickness can be made uniform as a whole. That is, it is possible to prevent the knock holes 16d1 and 16d2 from being blocked by the coating, and when the fixing plate 16 is temporarily fixed to the engine block 1b, the knock pins can be easily inserted into the knock holes 16d1 and 16d2. Further, when the fixing plate 16 is bolted to the engine block 1b and the housing 15, they can be brought into surface contact over the entire circumference of the flange portion 16a and the contact surface pressure can be made substantially the same.

  When the engine 1 of the vehicle equipped with the power transmission device is stopped, the foreign matter that has entered the engine side space SE and the transmission mechanism side space ST moves below the spaces SE and ST by gravity, for example. To do. When the engine is operated, the above air flow is generated, and is discharged to the outside of the housing 15 through the through holes 20 and 25 together with the air flow.

  DESCRIPTION OF SYMBOLS 1 ... Engine, 1a ... Output shaft, 1b ... Engine block, 14 ... One-way clutch (lock mechanism), 14b ... Outer ring (movable member), 15 ... Housing, 16 ... Fixed plate (fixed member), 20 ... 1st through-hole 25 ... 2nd through-hole, 26a, 26b ... rib.

Claims (1)

A lock mechanism configured to rotate the output shaft of the engine in only one direction and prevent rotation in a direction opposite to the one direction is disposed between the engine and the transmission mechanism, and the lock mechanism is fixed A member and a movable member, the movable member is coupled to the output shaft, and the fixed member is fixed between a housing of the transmission mechanism and an engine block of the engine, and is formed by the housing and the engine block In the power transmission device in which the space to be divided into the engine side space and the transmission mechanism side space by the lock mechanism,
The housing side of the engine block, the multiple ribs extending radially provided from said output shaft,
A first through hole that communicates the engine-side space and the transmission-mechanism-side space is formed at a position below the fixing member and below the engine block and between the adjacent ribs. ,
A second through hole is formed in the lower portion of the housing to communicate between the inside and the outside of the transmission mechanism side space between the ribs and between the ribs ;
The power transmission device, wherein the second through hole is displaced from a region where the lock mechanism is disposed in the axial direction and is located below the first through hole .

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