JP6795427B2 - Internal combustion engine - Google Patents

Description

The present invention relates to an internal combustion engine provided with auxiliary equipment such as an ISG (integrated starter generator, a generator with a motor function) and a water pump, and is particularly suitable for an internal combustion engine for vehicles (for automobiles). It is targeted.

Internal combustion engines for vehicles are accompanied by electrical auxiliary equipment such as alternators and ISGs, and auxiliary equipment such as water pumps and compressors for air conditioners. Therefore, one end of the crankshaft is projected to the outside of the engine body, the crank pulley is fixed to this, and each auxiliary machine and the crankshaft are interlocked via a belt (belt for auxiliary machine) wrapped around the crank pulley. ing.

There are various interlocking mechanisms by belts, but they can be classified according to the arrangement of auxiliary equipment and the number of belts. For example, Patent Document 1 discloses that a plurality of auxiliary machines are positioned close to one side of the engine body with the cylinder bore axis sandwiched between them when viewed from the crank axis direction, and each auxiliary machine is driven by one belt. Has been done.

On the other hand, in Patent Document 2 , the motor generator and other auxiliary machines are arranged separately on both sides of the cylinder bore axis when viewed from the crank axis direction, and the pulleys of these motor generators and the pulleys of other auxiliary machines are arranged. A mode in which one belt is wrapped around the vehicle is disclosed. Since slippage easily occurs between the pulley of the motor generator and the belt, it is common that the belt wound around the pulley of the motor generator secures a predetermined tension with a tensioner. However, the tension pulley is rotatably applied to the belt.

In the above two examples, one belt was wound around the pulley of each auxiliary machine, but in Patent Document 3, when an ISG, a water pump, and a compressor for an air conditioner are provided as auxiliary machines, each of these cases is provided. An example is disclosed in which separate belts are wound around the pulley of an auxiliary machine. Therefore, in Patent Document 3, the three belts are arranged so as to be offset in the crank axis direction, and the crank pulley is formed with a pulley portion (winding portion) corresponding to the three belts.

Further, in Patent Document 3, the ISG and the water pump are arranged on one side of the cylinder bore axis when viewed from the crank axis direction, and the air conditioner compressor is arranged on the one side of the cylinder bore axis. Further, the water pump is integrally provided in the engine body, and the ISG is arranged so as to be located outside the engine body. Therefore, when viewed from the crank axis direction, the ISG is farther from the crank axis than the water pump.

In Patent Document 3, the ISG belt is arranged so as to surround the belt for the water pump, and by sandwiching the belt from above and below with a pair of tension pulleys, the belt holds the ISG pulley in a state of being embraced. ing.

Japanese Unexamined Patent Publication No. 2013-108377 Japanese Unexamined Patent Publication No. 2011-017393 (Fig. 2) Japanese Unexamined Patent Publication No. 2015-183636

The arrangement of the auxiliary machines is determined in consideration of various factors, and it is not possible to simply compare the superiority and inferiority. However, as in Patent Document 1, the mode in which each auxiliary machine is driven by one belt is described. There is a problem that the load on the belt is large because the belt is bent greatly, and there is a problem that the bending force acts on the crankshaft from only one direction, which hinders the smooth rotation of the crankshaft. In addition, if all the auxiliary machines are moved to one side of the engine body, there is a problem that the stability of the engine deteriorates.

On the other hand, in the case of Patent Document 2, since the auxiliary machines are distributed to the left and right, it can contribute to the improvement of the stability of the engine, but since there is only one belt, the belt is similar to Patent Document 1. There remains the problem that the burden on the crankshaft is heavy and that a large bending force acts on the crankshaft, which hinders smooth rotation.

On the other hand, in the configuration of Patent Document 3, since the ISG and the compressor for the air conditioner are arranged separately on the left and right, not only can it contribute to the improvement of the stability of the engine, but also the belts of each auxiliary machine are independent. Therefore, the durability of the belt can be improved, and an appropriate winding mode can be ensured for the pulley of each auxiliary machine. Further, since the crank pulley is pulled in different directions by different belts, the bending force with respect to the crankshaft is canceled out, which has an advantage that it can contribute to the smooth rotation of the crankshaft.

The present invention has been made in view of such a current situation, and when a plurality of auxiliary machines are arranged close to one side of the engine body as in Patent Document 3, the interlocking mechanism composed of a belt and a tensioner is made compact. The challenge is to provide an internal combustion engine that is better than before.

The invention of the present application is
"On one side of the engine body across the cylinder bore axis when viewed from the crank axis direction, the electrical system auxiliary machine and the water pump are separated from the cylinder bore axis than the water pump. It is placed on the side and on the lower side,
The first belt is wound around the electric auxiliary machine pulley and the crank pulley provided in the electric system auxiliary machine, and the second belt is wound around the water pump pulley and the crank pulley provided in the water pump. , The first belt and the second belt are arranged so as to be offset in the crank axis direction.
Further, the tension pulley is rotatably contacted with the first belt from above. "
It is a basic configuration.

In the invention of claim 1, in the basic configuration, the axial center of the tension pulley is a triangular area connecting the axial center of the electrical auxiliary machine pulley, the axial center of the water pump pulley, and the axial center of the crank pulley. It is located within,
Further, the air conditioner compressor is arranged on the other side of the engine body across the cylinder bore axis when viewed from the crank axis direction, and the third belt is wound around the pulley of the air conditioner compressor and the crank pulley. The first belt to the third belt are arranged in the crank axis direction in the order of the second belt, the first belt, and the third belt in the order of proximity to the engine body.
In addition to ISG, electrical auxiliary equipment includes those having a rotor, such as a motor generator and an alternator.

In the invention of claim 2, in the basic configuration, the first belt and the second belt are arranged so that the second belt is located closer to the engine body than the first belt, and the tension. The pulley is arranged so as to partially overlap the second belt when viewed from the crank axis direction .
Further, the air conditioner compressor is arranged on the other side of the engine body across the cylinder bore axis when viewed from the crank axis direction, and the third belt is wound around the pulley of the air conditioner compressor and the crank pulley. The first belt to the third belt are arranged in the crank axis direction in the order of the second belt, the first belt, and the third belt in the order of proximity to the engine body.

In the invention of claim 1, so to speak, the tension pulley is arranged in the area surrounded by the electric system auxiliary machine, the water pump, and the crank pulley, so that the space is effectively used to make the interlocking mechanism compact. be able to. Therefore, it can contribute to the compactification of the engine as a whole, and also expand the freedom of selection of the arrangement position of other devices and devices, and contribute to the improvement of the design freedom of the engine as a whole.

Further, since the tension pulley is deeply inserted between the electric system auxiliary machine and the crank pulley, the first belt can be held in a state where the pulley of the electric system auxiliary machine is firmly held. Therefore, slippage between the pulley of the electric system auxiliary machine and the first belt can be prevented, and power transmission can be ensured.

Also in the invention of claim 2, since the tension pulley overlaps a part of the second belt in the direction of the crank axis, the tension pulley is moved to the arrangement area of the second belt, so that the space is effectively used as in claim 1. As a result, the interlocking mechanism can be made compact, which contributes to the compactness of the entire engine and also expands the freedom of selection of the placement position of other devices and devices, improving the freedom of design. Can also contribute.

Further, in claim 2, since the tension pulley is located outside the second belt, the tension pulley acts as a cover for the second belt, and has an advantage that, for example, a collision of pebbles flipped up during traveling can be prevented. Is also possible.

Further, in the inventions of both claims , since the pulling direction of the crankshaft by the first belt and the second belt is different from the pulling direction of the crankshaft by the third belt, the bending force with respect to the crankshaft is reduced and smooth rotation is performed. Can contribute to.

Further, since the electric auxiliary equipment such as ISG and the motor generator has a large rotational inertial force and a large load, the bending force acting on the crankshaft via the first belt also increases. In both inventions, the first Since the belt is located closer to the engine body than the third belt for the compressor for air conditioners, the moment acting on the crankshaft via the first belt is suppressed to ensure smooth rotation of the crankshaft. Can be improved.

Further, since the water pump pulley is brought close to the engine body, the length of the rotation shaft of the water pump can be shortened as much as possible. As a result, the bending moment acting on the rotating shaft can be suppressed, which can contribute to the improvement of the sealing property. In addition, the rotation resistance can be reduced by eliminating the twisting of the rotation shaft.

It is a front view of an internal combustion engine. It is a partially enlarged front view of an internal combustion engine. (A) is a sectional view taken along line IIIA-IIIA of FIG. 1, and FIG. 1B is a sectional view taken along line IIIB-IIIB of FIG. FIG. 2 is a view seen from the IV-IV viewing direction (the belt is almost omitted). It is a VV sectional view of FIG.

(1). Outline Next, an embodiment of the present invention will be described with reference to the drawings. First, an outline of the internal combustion engine will be described mainly based on FIGS. 1 and 2. The internal combustion engine of the present embodiment is mounted on a vehicle, and includes a cylinder block 1, a cylinder head 2 fixed to the upper surface thereof, and a front cover 3 fixed to the front surface thereof as an engine main body. The timing chain is covered with the front cover 3. A head cover 4 is fixed to the upper surface of the cylinder head 2, and an oil pan 5 is fixed to the lower surface of the cylinder block 1. The head cover 4 and the oil pan 5 also constitute the engine body.

The crankshaft 6 is rotatably held in the cylinder block 1. One end of the crankshaft 6 penetrates the front cover 3 and is exposed toward the front, and the crank pulley 7 is fixed to the exposed end. In the present embodiment, the ISG 8, the water pump 9, and the air conditioner compressor 10 are provided as auxiliary machines, and these are provided with pulleys 11, 12, and 13, respectively.

FIG. 1 is a front view seen from the crank axis direction. In this front view, the ISG 8 is arranged on the left outer side of the engine body, and the water pump 9 is on the left side of the engine body with the cylinder bore axis 14 in between. It is located near the site. On the other hand, the air conditioner compressor 10 is arranged outside the engine body on the right side of the cylinder bore axis O. Therefore, the ISG 8 and the water pump 9 are arranged closer to the left, and the air conditioner compressor 10 is arranged closer to the right.

The ISG 8 is an example of an electric system auxiliary machine having a rotor, and includes a housing 15 and an ISG pulley 11 fixed to the rotor. Therefore, the ISG pulley 11 corresponds to the electrical auxiliary equipment pulley described in the claims. The housing 15 is fixed to the front cover 3 and the cylinder block 1 via the bracket 16. The first belt 17 is wound around the ISG pulley 11 and the crank pulley 7, and the tension pulley 19 of the auto tensioner 18 is rotatably abutted on the first belt 17 from above.

The main body (pump chamber, etc.) of the water pump 9 is built in the front cover 3, the water pump pulley 12 fixed to the rotating shaft is exposed, and the second belt 20 is attached to the water pump pulley 12 and the crank pulley 7. Is wrapped around. Since the water pump pulley 12 is closest to the surface of the front cover 3, the length of the rotation shaft of the water pump 9 is also shortened. Therefore, it is possible to prevent bending of the rotating shaft and ensure high sealing performance.

The air conditioner compressor 10 is fixed to the cylinder block 1 via a bracket 21, and a third belt 22 is wound around a pulley (air conditioner pulley) 13 and a crank pulley 7 of the air conditioner compressor 10.

As shown in FIG. 5, in the three belts 17, 20 and 22, the second belt 20 is located closest to the front cover 3, the third belt 22 is located farthest from the front cover 3, and the first belt 17 Is located between the two. Therefore, the crank pulley 7 is formed with three pulley portions 7a, 7b, and 7c. The inner surfaces of the belts 17, 20, and 22 have a serrated cross section, and therefore the outer peripheral surfaces of the pulleys 7, 11, 12, and 13 also have a serrated cross section.

(2). Tensioner, etc. The auto tensioner 18 has a stretchable absorber (elastic device) 23 in which a spring and an oil damper are built in a case that is fitted so as to be movable relative to each other, and the tip (lower end) of the absorber 23. The portion) has a plate-shaped arm (bracket) 25 connected by the first pin 24, and the tension pulley 19 is rotatably connected to the lower end of the arm 25 by the second pin (shaft) 26. There is. The arm 25 has a dotaku shape with an arc-shaped lower portion, and the right end portion of the upper end portion closer to the cylinder bore axis 14 side is connected to the tip end portion of the absorber 23 by the first pin 24 to form the upper end portion. Of these, the left end portion away from the cylinder bore axis O is connected to the housing 15 of the ISG 8 by a third pin 27.

Since the arm 25 is separated from the housing 15 of the ISG8 toward the front, a boss 28 projecting toward the front (toward the direction away from the engine body) is integrally provided with the housing 15 of the ISG8, and the arm 25 is integrally provided with the boss 28. Is connected by the third pin 27. The arm 25 may be connected to the bracket 16 to which the ISG 8 is attached, or may be connected to the front cover 3 or the cylinder head 2 with a dedicated bracket. Further, it is also possible to integrally form a forward protruding boss on the front cover 3 and connect the arm 25 to the forward protruding boss.

The upper end of the absorber 23 in the auto tensioner 18 is connected to the front cover 3 by the fourth pin 29. In this case, as shown in FIG. 3, a forward overhanging portion 31 having an inclined surface 30 on the lower surface is formed on the upper portion of the front cover 3, and a receiving seat 32 formed on the inclined surface 30 of the forward overhanging portion 31 is formed. , The upper end of the absorber 23 is rotatably connected by the fourth pin 29. Therefore, in a plan view, a corresponding portion of the auto tensioner 18 is hidden by the forward overhanging portion 31.

The tension pulley 19 of the auto tensioner 18 is arranged on the rear surface of the arm 25. Therefore, although the tension pulley 19 is covered from the front by the arm 25, the arm 25 is set to a size that covers the entire tension pulley 19.

As is clearly shown in FIG. 2, the axis of the tension pulley 19 connects the axis of the ISG pulley 11, the axis of the crank pulley 7, and the axis of the water pump pulley 12 when viewed from the front view from the crank axis direction. It is located inside the triangle 33 surrounded by a line. Therefore, the interlocking mechanism can be compactly integrated and the space can be effectively used.

Further, when viewed from the front view from the crank axis direction, a part of the tension pulley 19 overlaps with a part of the second belt 20, and this configuration also contributes to compactness by effectively utilizing the space. By overlapping the tension pulley 19 and the second belt 20 in the crankshaft direction in this way, the ISG 8 can be moved as close to the crank pulley 7 as possible, so that the internal combustion engine moves the crankshaft 6 in the direction orthogonal to the traveling direction of the vehicle. When placed in the engine room in a long transverse position, the width of the engine as seen in the front-rear direction of the vehicle can be made as small as possible, so that the distance that the engine retreats when the vehicle collides with something in an accident can be minimized. By making it larger, it can also contribute to cushioning the impact on passengers.

Further, when the arm 25 is formed in the shape of a plate and substantially in the shape of a dotaku as in the embodiment, the arm 25 acts as a cover for the tension pulley 19 and the second belt 20, so that the tension pulley 19 and the second belt 20 are protected. It has the advantage of improving functionality.

In the present embodiment, the arm 25 moves along an arc locus 34 centered on the left end portion of the upper end portion close to the ISG pulley 11, so that when the absorber 23 extends, the tension pulley 19 approaches the ISG pulley 11. Try. Therefore, the contact length between the first belt 17 and the ISG pulley 11 is lengthened (the tension pulley 19 is largely embraced by the first belt 17), and a high anti-slip effect can be realized.

In FIG. 2, the state in which one belt is wound around the crank pulley 7, the ISG pulley 11, and the water pump pulley 12 is shown as a virtual belt by the alternate long and short dash line 35. However, in the present embodiment, the arm 25 is large. Since the portion is contained in the range surrounded by the virtual belt 35, the interlocking mechanism using the first belt 17 and the second belt 20 as the transmission means can be further made more compact. The entire arm 25 may be arranged inside the virtual belt 35.

Further, in the present embodiment, the expansion / contraction direction 36 of the absorber 23 and the pushing direction 37 of the first belt 17 by the tension pulley 19 are obliquely inclined in the same direction with respect to the cylinder bore axis 14 when viewed from the crank axis direction. It is pointing downwards. Therefore, the elastic restoring force (spring force) of the absorber 23 can be transmitted straight to the tension pulley 19. Therefore, the absorber 23 can be prevented from being twisted, and the tension state of the first belt 17 can be accurately maintained.

That is, the ISG 8 has three states: a state in which it functions as a motor, a state in which it functions as a generator, and a state in which it is idling. When the state changes, the tension state of the first belt 17 also changes. In the embodiment, the movement of the crank pulley 7 in response to the change in the tension state is performed with good responsiveness in a state where the absorber 23 is not twisted.

A cooling water jacket is formed on the cylinder block 1 and the cylinder head 2, and cooling water is sent to the cylinder head 2 from a communication hole formed in the cylinder block 1. In the cylinder head 2, the temperature change of the cylinder head 2 due to cooling is generally minimized by flowing cooling water from the intake side to the exhaust side.

In the internal combustion engine of the embodiment, the right side is the exhaust side and the left side is the intake side in FIGS. 1 and 2, but in the present embodiment, the water pump 9 is arranged closer to the intake side (intake side surface). Therefore, there is an advantage that the water passage from the outlet of the water pump 9 to the cylinder head 2 can be shortened to suppress pressure loss.

Since the ISG 8 and the air conditioner compressor 10 are arranged at opposite positions, the bending force acting on the crankshaft 6 by the first belt 17 and the bending force acting on the crankshaft 6 by the third belt 22 cancel each other out. Therefore, the load on the crankshaft 6 can be reduced. In this case, as shown by arrows 38, 39, and 40 in FIG. 1, since the tension pulley 19 enters downward between the ISG pulley 11 and the crank pulley 7, the bending force of the crankshaft 6 by the first belt 17 The action direction 40 is a posture lying on the horizontal side with respect to the direction 39 connecting the axial centers of the ISG 8 and the crank pulley 7.

Therefore, the angle formed by the pulling direction 40 of the first belt 17 with respect to the crankshaft 6 and the pulling direction 38 of the third belt 22 with respect to the crankshaft 6 is close to 180 degrees. Therefore, even if the ISG 8 and the air conditioner compressor 10 are arranged at positions higher than the crankshaft 6, the bending force acting on the crankshaft 6 can be further reduced.

Although the embodiments of the present invention have been described above, the present invention can be embodied in various ways. For example, in the above embodiment, the tension pulley is connected to the rotary arm, but it is also possible to attach the tension pulley to a slider that slides in the same direction as the expansion and contraction direction of the absorber. Further, as the tensioner device, a remote control type device in which the tension pulley is moved and operated by an actuator such as an electromagnetic solenoid can also be adopted.

The invention of the present application can be actually embodied in an internal combustion engine. Therefore, it can be used industrially.

1 Cylinder block that constitutes the engine body 2 Cylinder head that constitutes the engine body 3 Front cover (chain cover) that constitutes the engine body
6 Crankshaft 7 Crank pulley 8 ISG as an example of electrical auxiliary equipment
9 Water pump 10 Air conditioner compressor 11 ISG pulley as an example of electrical auxiliary equipment pulley 12 Water pump pulley 13 Air conditioner pulley 17 1st belt 18 Auto tensioner as an example of tensioner device 19 Tension pulley 20 2nd belt 22 3rd belt 23 Auto tensioner absorber 25 Auto tensioner arm 33 Triangle

Claims (2)

On one side of the engine body across the cylinder bore axis when viewed from the crank axis direction, the electrical system auxiliary equipment and the water pump are located on the side where the electrical system auxiliary equipment is farther from the cylinder bore axis than the water pump. It is placed in a state where it is located on the lower side,
The first belt is wound around the electric auxiliary machine pulley and the crank pulley provided in the electric system auxiliary machine, and the second belt is wound around the water pump pulley and the crank pulley provided in the water pump. , The first belt and the second belt are arranged so as to be offset in the crank axis direction.
Further, the tension pulley is rotatably contacted with the first belt from above.
The axis of the tension pulley is located in a triangular area connecting the axis of the electrical auxiliary equipment pulley, the axis of the water pump pulley, and the axis of the crank pulley .
Further, the air conditioner compressor is arranged on the other side of the engine body across the cylinder bore axis when viewed from the crank axis direction, and the third belt is wound around the pulley of the air conditioner compressor and the crank pulley. The first belt to the third belt are arranged in the crank axis direction in the order of the second belt, the first belt, and the third belt in the order of proximity to the engine body.
Internal combustion engine. On one side of the engine body across the cylinder bore axis when viewed from the crank axis direction, the electrical system auxiliary equipment and the water pump are located on the side where the electrical system auxiliary equipment is farther from the cylinder bore axis than the water pump. It is placed in a state where it is located on the lower side,
The first belt is wound around the electric auxiliary machine pulley and the crank pulley provided in the electric system auxiliary machine, and the second belt is wound around the water pump pulley and the crank pulley provided in the water pump. , The first belt and the second belt are arranged so as to be offset in the crank axis direction.
Further, the tension pulley is rotatably contacted with the first belt from above.
The tension pulley is arranged so as to partially overlap the second belt when viewed from the crank axis direction .
Further, the air conditioner compressor is arranged on the other side of the engine body across the cylinder bore axis when viewed from the crank axis direction, and the third belt is wound around the pulley of the air conditioner compressor and the crank pulley. The first belt to the third belt are arranged in the crank axis direction in the order of the second belt, the first belt, and the third belt in the order of proximity to the engine body.
Internal combustion engine.

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