JP5030041B2 - Engine starting torque transmission mechanism - Google Patents

Description

  The present invention relates to an engine start torque transmission mechanism that transmits torque for engine start to an engine crankshaft.

In general automobiles, in order to start the engine, a starter motor is energized, and the rotational force is transmitted to the crankshaft to rotate the crankshaft. That is, the engine is started by interposing a gear mechanism between the starter motor and the crankshaft and meshing the gears to transmit the rotational force. When the crankshaft rotates to complete the start, the meshing of the gears is released and the energization to the starter motor is stopped.
Such an engine start torque transmission mechanism of an automobile has a structure in which a gear is meshed at the time of start, and the mesh is released after the start.

However, in recent years, in order to reduce carbon dioxide emissions and improve fuel efficiency, automobile engines are not idling when the automobile is temporarily stopped due to a signal, etc. Therefore, it is required to stop (so-called idling stop).
In a car equipped with an idling stop system, the engine is automatically stopped when the vehicle is temporarily stopped. If it is determined that there is a restart request from the driver, an activation signal is sent to the starter motor, and the engine is automatically started instantaneously. As an engine starting rotational force transmission mechanism incorporated in such an automobile, a structure using a gear mechanism, a one-way clutch, a bearing or the like is considered.

FIG. 5 is a diagram showing a conventional example of such an engine starting rotational force transmission mechanism. First, the structure will be described, and then the operation will be described.
In FIG. 5, 1 is an engine starting torque transmission mechanism, 2 is a starter motor, 2P is a pinion gear, 3 is a ring gear, 4 is an engine block, 5 is a drive plate (first drive plate), and 6 is a drive plate (second drive). Drive plate), 7 and 8 are oil seals, 9 is a one-way clutch, 10 is a bearing, 11 is an inner race, 12 is an outer race, 13 is a one-way clutch operating part, 14 is an outer ring, 15 is a ball rolling element, and 16 An inner ring, 17 is a bolt, 18 is a crankshaft, 19 is a crank bearing portion, 20 is an oil supply hole, 21 is an oil jet hole, and 22 is a crank bearing.

The drive plate 5 is a drive plate having a ring gear 3 fixed to the outer periphery thereof. The drive plate 6 is disposed at a position farther from the drive plate 5 when viewed from the engine block 4, and a central portion is fixed to the crankshaft 18. Drive plate.
The pinion gear 2 </ b> P is a gear connected to the starter motor 2 and rotated by the starter motor 2. The rotational force for starting is transmitted from this gear to the ring gear 3. Therefore, it can be said that the starter motor 2 and the pinion gear 2P are mechanisms that generate the starting rotational force, and the portion beyond the ring gear 3 can transmit the starting rotational force.
The ring gear 3 is a gear fixed to the outer periphery of the drive plate 5 and meshes with the pinion gear 2P at the start.
A one-way clutch 9 and a bearing 10 are provided between the drive plate 5 and the crankshaft 18.

The bearing 10 includes an inner ring 16, a ball rolling element 15, and an outer ring 14, and the inner ring 16 is fixed to a crankshaft 18.
The one-way clutch 9 is configured such that a one-way clutch operating unit 13 is sandwiched between an inner race 11 and an outer race 12. The one-way clutch actuating unit 13 is engaged so as to transmit the force when force is transmitted in a predetermined direction, and is operated so as not to transmit force when it is not engaged. Structure part.
Specifically, in this figure, when the rotational speed of the inner race 11 is larger than the rotational speed of the outer race 12, the engaged state is established (rotational force transmission from the inner race 11 to the outer race 12), and otherwise it is released. It becomes a state.

Of the end portions of the inner race 11, the end portion that holds the one-way clutch operating portion 13 is fixed to the outer periphery of the outer ring 14, and the other end portion is fixed to the inner periphery of the drive plate 5 by welding or the like. . The end of the outer race 12 that is not sandwiching the one-way clutch operating portion 13 is fixed to the crankshaft 18 by a bolt 17.
The drive plate 6 is also fixed to the rear end of the crankshaft 18 with bolts 17.

The oil seal 7 is a seal disposed between the engine block 4 and the inner race 11, and seals between the two so that engine oil or the like does not leak.
The oil seal 8 is a seal disposed between the inner race 11 and the outer race 12, and removes engine oil or the like leaking from the engine block 4 side through the bearing 10 and the one-way clutch 9 from this position. I'm stopping here so I don't go out.

An oil jet hole 21 communicating with the oil supply hole 20 to the crank bearing 22 provided in the crank bearing portion 19 of the engine block 4 is opened by metal processing from the side surface of the crank bearing portion 19 facing the bearing 10 and the like. ing.
Lubricating oil is supplied from a pump (not shown), is branched from a path for lubricating the crank bearing 22, and is ejected through the oil jet hole 21 to be used for lubricating the bearing 10, the one-way clutch 9, the oil seal 8, and the like. Lubricating oil and engine oil also play a role in preventing deterioration of oil seals and improving performance.

Next, the operation will be described.
(When starting)
Before starting, the crankshaft 18 is stopped, and the inner ring 16 fixed integrally therewith is also stopped. When the starter motor 2 is activated, the rotational force is transmitted to the inner race 11 through the following route. Pinion gear 2P → ring gear 3 → drive plate 5 → inner race 11. The inner race 11 to which the rotational force is applied is fixed to the outer periphery of the outer ring 14 of the bearing 10 and is stopped because the ball rolling element 15 is interposed between the outer ring 14 and the inner ring 16. It tries to rotate smoothly around the inner ring 16 (integrated with the crankshaft 18) (without rotating the inner ring 16).

  The outer race 12 is fixed to the crankshaft 18 and is stopped together with the crankshaft 18. If the inner race 11 tries to rotate in this state, the inner race 11 rotates at a higher rotational speed than the outer race 12, so that the one-way clutch actuating portion 13 is engaged. As a result, the rotational force of the inner race 11 is transmitted to the outer race 12, the crankshaft 18 secured thereto starts to rotate, and the engine is started.

(After startup is complete)
When the rotational speed of the crankshaft 18 is increased after starting, and the rotational speed of the outer race 12 becomes larger than the rotational speed of the inner race 11, the one-way clutch operating unit 13 is released. Then, the engagement relationship between the inner race 11 and the outer race 12 is lost, and thereafter each moves independently.

Since energization to the starter motor 2 is eventually turned off, the pinion gear 2P also stops. Therefore, the ring gear 3 meshing with the pinion gear 2P also stops rotating, and the drive plate 5, the inner race 11 and the outer ring 14 connected to the tip of the ring gear 3 also stop rotating.
Since the inner ring 16 is fixed to the crankshaft 18, it continues to rotate together with the crankshaft 18. However, the ball rolling element 15 is interposed between the outer ring 14 and the rotational force of the inner ring 16 is not transmitted to the outer ring 14. Therefore, the outer ring 14 does not rotate around.

JP 2007-032492 A

The above-described conventional engine starting torque transmission mechanism has been completed by assembling parts such as the bearing 10 to the engine block 4 and the crankshaft 18 one by one. However, since the assembly work is complicated and laborious, there is a problem that the manufacturing cost including labor is increased, the finished state is not uniform, and some variation occurs.
An object of the present invention is to solve such problems.

In order to solve the above problems, in the present invention, a ring gear meshed with a pinion gear of a starter motor, a first drive plate having an outer periphery fixed to the inner periphery of the ring gear, and the first drive as viewed from the engine block A second drive plate disposed at a position farther from the plate and having a central portion fixed to the crankshaft of the engine, and a starting rotational force transmission path between the first drive plate and the crankshaft; In the engine starting rotational force transmission mechanism comprising a one-way clutch for transmitting rotational force only in one direction from the drive plate side to the crankshaft side, the second drive from the ring gear in the path for transmitting the starting rotational force to the crankshaft the portion up to the plate unitized and transmission mechanism unit.

The structure of the transmission mechanism unit includes a ring gear, a one-way clutch filled with a lubricant and sealed to prevent lubricant leakage on both sides, and an inner periphery fixed to an inner race of the one-way clutch. A first drive plate fixed to the ring gear; a second drive plate having an outer race of the one-way clutch fixed to a side; and an outer peripheral surface of the inner race that is in rotational contact with the inner peripheral surface of the inner race; An oil-impregnated sliding bush provided with an engaging portion that engages with a side surface of the end portion of the race where the first drive plate is not fixed, and an outer periphery is fixed to an inner periphery of the oil-containing slip bush. serration key it is assumed that comprise the oil-bearing sliding bush support that has been subjected to.

On the other hand, a projecting cylindrical part is provided on the engine block, an oil seal is provided between the projecting cylindrical part and the crankshaft, and the inner periphery of the oil-impregnated sliding bush support is press-fitted so that it fits on the outer periphery of the projecting cylindrical part. The engine starting torque transmission mechanism is configured by assembling the transmission mechanism unit to the engine block and the crankshaft .

According to the engine starting rotational force transmission mechanism of the present invention, since most of the mechanism for transmitting the starting rotational force is unitized as a transmission mechanism unit, the engine start can be started only by assembling it to the engine block and the crankshaft. A rotational force transmission mechanism can be configured. And the assembly work is extremely simple and can be done in a short time, so that the manufacturing cost including labor can be greatly reduced.
In addition, since the parts are unitized with accuracy in advance at a site dedicated to component unit different from the engine assembly site, the finished state after completion of engine assembly is uniform, and variations do not occur.

Exploded view of the first embodiment of the present invention Assembly completion drawing of the first embodiment of the present invention Exploded view of the second embodiment of the present invention Assembly completion drawing of the second embodiment of the present invention The figure which shows the conventional engine starting rotational force transmission mechanism

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
FIG. 1 is an exploded explanatory view of a first embodiment relating to an engine starting rotational force transmission mechanism of the present invention, and FIG. 2 is an assembled view. The reference numerals correspond to those in FIG. 5, 23 is an oil-impregnated sliding bush, 23E is an engaging portion, 24 is an oil-containing sliding bush support, 24S is a serration key, 25 is an oil seal, 26 is a protruding cylindrical portion, and 27 is a bolt screw A hole, 28 is a bolt insertion hole, and 30 is a transmission mechanism unit.
The outline is as shown in FIG. 2 when the transmission mechanism unit 30 is assembled to the engine block 4 as shown by the arrow A in FIG. 1 and fixed to the crankshaft 18 with the bolts 17.

In this embodiment, a part ahead of the ring gear 3 which is a mechanism for transmitting the starting rotational force generated by the starter motor 2 (the pinion gear 2P is integrated therewith) in the engine starting rotational force transmission mechanism is previously transmitted to the transmission mechanism unit. The unit 30 is made into a unit, and is completed by simply assembling it to the engine block 4 and the crankshaft 18.
However, the transmission mechanism unit 30 is not simply formed as a unit by using the components in the transmission mechanism portion (the portion ahead of the ring gear 3) in FIG. The function as a transmission mechanism that transmits the starting torque is fulfilled in the same way. In addition, parts that are inexpensive, easy to maintain and easy to unitize are selected, and the structure that connects them is devised into a unit. . Further, the structure for assembling the engine block 4 is newly devised.

There are several structures shown in FIGS. 1 and 2 that are different from those in FIG. 5, but as described above, it is easy to unitize the transmission mechanism, or a unitized one. It was created to facilitate assembly.
The structures different from those in FIG. 5 are listed as follows.
(1) The inner peripheral portion of the drive plate 5 was fixed to the inner race 11 of the one-way clutch 9.
(2) The one-way clutch 9 was filled with a lubricant and sealed on both sides to prevent leakage of the lubricant.
(3) The bearing 10 was abolished and the oil-impregnated sliding bush 23 was adopted.
(4) Of the end portions of the inner race 11, the oil-impregnated sliding bush 23 including the engaging portion 23E that engages the side surface of the end portion to which the drive plate 5 is not fixed is the inner peripheral surface of the inner race 11. It was made the structure which can be made to contact with rotation.
(5) The outer periphery of the oil-impregnated sliding bush support 24 is fixed to the inner periphery of the oil-impregnated sliding bush 23, and the serration key 24S is applied to the inner periphery of the oil-impregnated sliding bush support 24.
(6) An oil seal 25 is provided between the inner peripheral surface of the protruding cylindrical portion 26 of the engine block 4 and the outer peripheral surface of the crankshaft 18.

Now, the structure of the first embodiment will be described in detail step by step (note that the description of the same part as in FIG. 5 is omitted or simplified).
The portion ahead of the ring gear 3 that transmits the starting rotational force is unitized as a transmission mechanism unit 30 as shown in FIG.
The inner peripheral end of the drive plate 5 to which the ring gear 3 is fixed on the outer periphery is fixed to one end of the inner race 11 of the one-way clutch 9 (for example, by welding, mechanical connection, etc.). The inner race 11 has a simple ring shape.
The outer race 12 of the one-way clutch 9 is fixed to the side surface of the drive plate 6.
The one-way clutch 9 used in the transmission mechanism unit 30 is of a type in which a lubricant is filled in advance and seals are provided on both sides to prevent leakage of the lubricant.

The inner peripheral surface of the inner race 11 is smoothly rotated and brought into contact with the oil-impregnated sliding bush 23 disposed inside thereof. The oil-impregnated sliding bush 23 is a sliding bush previously impregnated with lubricating oil, and can maintain smooth lubrication without having to be supplied with lubricating oil from the outside.
One end of the oil-impregnated sliding bush 23 is provided with an engaging portion 23E that engages with the side surface of the other end of the inner race 11 (the end to which the drive plate 5 is not fixed). The engaging portion 23E is for preventing the oil-impregnated sliding bush 23 from slipping and dropping in the axial direction with respect to the inner race 11.

The outer peripheral surface of the oil-containing sliding bush support 24 is fixed to the inner peripheral surface of the oil-containing sliding bush 23. A serration key 24S is provided on the inner peripheral surface of the oil-impregnated sliding bush support 24.
A transmission mechanism unit 30 is obtained by unitizing a required structure as described above.

The engine block 4 is provided with a protruding cylindrical portion 26 as a structural portion that supports the oil-impregnated sliding bush support 24. The outer periphery of the protruding cylindrical portion 26 is made to have a size that fits with the inner periphery of the oil-impregnated sliding bush support 24 (with the serration key 24S).
When the transmission mechanism unit 30 is assembled, the inner periphery of the oil-impregnated sliding bush support 24 is press-fitted to the outer periphery of the protruding cylindrical portion 26, but the inner periphery is provided with serration keys 24S. It is hard to prevent the bush support 24 from rotating in the circumferential direction.

The oil seal 25 is an oil seal disposed between the inner peripheral surface of the protruding cylindrical portion 26 provided on the engine block 4 and the outer peripheral surface of the crankshaft 18. This is to prevent engine oil, lubricating oil, and the like from the engine block 4 side and prevent leakage to the outside (to the right from the oil seal 25 in FIG. 1).
Since the one-way clutch 9 and the oil-impregnated sliding bush 23 employed in the transmission mechanism unit 30 of the present invention do not require supply of lubricating oil from others, the oil seal 25 may block the lubricating oil or the like.

  In the conventional example shown in FIG. 5, an oil jet hole 21 is formed in the crank bearing portion 19, from which the lubricating oil is ejected and used to lubricate the one-way clutch 9 and the bearing 10. However, in the present invention, the bearing 10 is eliminated, and the one-way clutch 9 uses a type that holds the lubricant therein, and the oil-impregnated sliding bush 23 holds the lubricating oil by itself. There is no need to supply. Therefore, the oil jet hole 21 for ejecting the lubricating oil is not necessary. Therefore, there is no need for metal processing to form it, and the cost is reduced accordingly.

In order to assemble the transmission mechanism unit 30 as described above to the engine block 4 and the crankshaft 18, only the following work is required.
(1) The inner periphery of the oil-impregnated sliding bush support 24 on the transmission mechanism unit 30 side is fitted to the outer periphery of the protruding cylindrical portion 26 on the engine block 4 side, and press-fitted in the direction of arrow A.
(2) The bolt 17 is inserted into the bolt insertion hole 28 of the drive plate 6 and screwed into the bolt screw hole 27.
Therefore, the assembling work can be done very easily and in a short time, and the manufacturing cost including labor can be greatly reduced. In addition, since the parts are unitized with accuracy in advance at a site dedicated to component unit different from the engine assembly site, the finished state after completion of engine assembly is uniform, and variations do not occur.

Next, the operation of the engine starting rotational force transmission mechanism completed as shown in FIG. 2 will be described.
(When starting)
The crankshaft 18 is stopped, and the drive plate 6 and the outer race 12 fixed integrally therewith are also stopped. When the starter motor 2 is started, the rotational force is transmitted to the inner race 11 of the one-way clutch 9 through a path of pinion gear 2P → ring gear 3 → drive plate 5 → inner race 11. The inner race 11 starts to rotate smoothly while being in rotational contact with the oil-impregnated sliding bush 23.

  At this time, since the outer race 12 is stopped together with the drive plate 6 and the crankshaft 18 that are integrally fixed, the inner race 11 to be rotated rotates more than the stopped inner race 12. Will do. Then, the one-way clutch operating unit 13 is engaged, and the rotational force of the inner race 11 is transmitted from the outer race 12 to the drive plate 6 to the crankshaft 18. Then, the crankshaft 18 starts rotating and the engine is started.

(After startup is complete)
When the rotational speed of the crankshaft 18 is increased after starting, and the rotational speed of the outer race 12 rotating together with the crankshaft 18 becomes larger than the rotational speed of the inner race 11, the one-way clutch operating unit 13 is Released state. Then, the engagement relationship between the outer race 12 and the inner race 11 is lost, and thereafter each moves independently.
The inner race 11 will eventually stop. This is because the energization of the starter motor 2 is eventually turned off, and the pinion gear 2P is also stopped. For this reason, the ring gear 3 meshing with the pinion gear 2P also stops rotating, and the drive plate 5 and the inner race 11 that are connected to the ring gear 3 also stop rotating.
Since the outer race 12 is fixed to the drive plate 6, it continues to rotate together with the crankshaft 18.

(Number of revolutions on oil-impregnated sliding bush 23)
The period during which the inner race 11 rotates while in contact with the oil-impregnated sliding bush 23 is a period from the start to the completion of the start (the inner race 11 remains stopped on the oil-impregnated slip bush 23 thereafter). As is well known, the number of rotations during this period is about several hundreds of rotations at most, and the time for which rotation is performed is extremely short. Therefore, the oil-impregnated sliding bush 23 does not have to be of high performance that can withstand high rotation and long-time operation, and its cost can be reduced.

(Second Embodiment)
FIG. 3 is an exploded explanatory view of a second embodiment related to the engine starting rotational force transmission mechanism of the present invention, and FIG. 4 is an assembled view. Reference numerals correspond to those in FIGS. 1 and 2, and 31 is a transmission mechanism unit.
If the transmission mechanism unit 31 is assembled to the engine block 4 as shown by the arrow A in FIG.
Since most of the second embodiment is the same as the first embodiment, the description of the same configuration and effect is omitted to avoid duplication, and different points will be described below.

In this embodiment, the number of parts included in the transmission mechanism unit 31 is reduced compared to that of the first embodiment. That is, the transmission mechanism unit 31 of the first embodiment, which excludes the oil-containing sliding bush 23 and the oil-containing sliding bush support 24, is unitized as a transmission mechanism unit 31.
The oil-impregnated slip bush 23 and the oil-impregnated slip bush support 24 excluded from the unitization are attached to the protruding cylindrical portion 26 of the engine block 4 prior to the assembly of the transmission mechanism unit 31.

3 and 4 show the structure in which the oil-impregnated sliding bush support 24 is interposed between the protruding cylindrical portion 26 and the oil-impregnated sliding bush 23, but the oil-impregnated sliding bush support 24 may be eliminated. . That is, the protruding cylindrical portion 26 may be of a size that also serves as the oil-impregnated sliding bush support 24, and the oil-containing sliding bush 23 may be directly fixed to the protruding cylindrical portion 26.
It goes without saying that the engine starting torque transmission mechanism of the present invention described above can be used not only for AT vehicles but also for MT vehicles.

  DESCRIPTION OF SYMBOLS 1 ... Engine starting rotational force transmission mechanism, 2 ... Starter motor, 2P ... Pinion gear, 3 ... Ring gear, 4 ... Engine block, 5, 6 ... Drive plate, 7, 8 ... Oil seal, 9 ... One-way clutch, 10 ... Bearing, DESCRIPTION OF SYMBOLS 11 ... Inner race, 12 ... Outer race, 13 ... One-way clutch operation part, 14 ... Outer ring, 15 ... Ball rolling element, 16 ... Inner ring, 17 ... Bolt, 18 ... Crankshaft, 19 ... Crank bearing part, 20 ... Oil supply hole , 21 ... Oil jet hole, 22 ... Crank bearing, 23 ... Oil-containing sliding bush, 23E ... Engagement part, 24 ... Oil-containing sliding bush support, 24S ... Serration key, 25 ... Oil seal, 26 ... Projecting cylindrical part, 27 ... Bolt screw hole, 28 ... bolt insertion hole, 30, 31 ... transmission mechanism unit

Claims (1)

A ring gear meshed with the starter motor pinion gear;
A first drive plate having an outer periphery fixed to the inner periphery of the ring gear;
A second drive plate disposed at a position far from the first drive plate as viewed from the engine block and having a central portion fixed to the crankshaft of the engine;
Engine start rotation comprising a one-way clutch disposed in a starting torque transmission path between the first drive plate and the crankshaft and transmitting torque in only one direction from the first drive plate to the crankshaft In the force transmission mechanism,
The unit from the ring gear to the second drive plate in the path for transmitting the starting rotational force to the crankshaft is unitized to form a transmission mechanism unit.
The structure of the transmission mechanism unit
Ring gear ,
One-way clutch filled with lubricant and sealed on both sides to prevent lubricant leakage ,
A first drive plate having an inner periphery fixed to the inner race of the one-way clutch and an outer periphery fixed to the ring gear ;
The outer circumference of the second drive plate with the outer race of the one-way clutch fixed to the side surface and the inner peripheral surface of the inner race are brought into rotational contact, and the first drive plate of the inner race is not fixed. An oil-impregnated sliding bush provided with an engaging portion that engages with a side surface of the other end ,
An oil-impregnated sliding bush support having an outer periphery fixed to the inner periphery of the oil-impregnated sliding bush and a serration key applied to the inner peripheral surface;
And
A projecting cylindrical part is provided on the engine block ,
An oil seal is provided between the protruding cylindrical portion and the crankshaft ,
An engine starting rotational force transmission mechanism characterized in that the transmission mechanism unit is assembled to an engine block and a crankshaft by press-fitting so that an inner periphery of the oil-impregnated sliding bush support is fitted to an outer periphery of the protruding cylindrical portion. .

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