JPH11173154A - Mechanical supercharger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the front projection area of a vehicle with a compact structure, enable precise control of intake flow rate, and improve fuel consumption with a simple structure and a low cost. SOLUTION: A mechanical supercharger is provided with an air compressor 5 to be driven by an engine 3, a motor 9 to drive the compressor 5, a controller 25 which stops the motor 9 when the number of engine revolution exceeds the prescribed value, and drives the compressor 5 by the motor 9 when the number of engine revolution becomes less than the prescribed value and a disengagement means 13 which disengages the compressor 5 from the engine 3 when the number of engine revolution becomes less than the prescribed value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a mechanical supercharger.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. 5-280608 discloses a mechanical supercharger 201 as shown in FIG.
No. 83923 discloses a supercharging device 203 as shown in FIG.

The mechanical supercharger 201 includes a belt type continuously variable transmission 205, a planetary gear type speed increasing mechanism 207, a centrifugal air compressor 209, and the like.

Similarly, the supercharging device 203 includes a belt type continuously variable transmission 211 and a planetary gear type speed increasing mechanism 213.
And a centrifugal air compressor 215.

[0005] The mechanical supercharger 201 and the supercharger 203 are
In each case, the driving force of the engine is transferred to the belt type continuously variable transmission 20.
The speed is changed at 5, 211, and the speed is further increased at the speed increasing mechanisms 207, 213 to drive the air compressors 209, 215, and the intake air is pressurized to supercharge the engine.

[0006] The belt-type continuously variable transmissions 205 and 211 reduce the engine driving force in a high-speed rotation region and increase the engine driving force in a middle / low-speed rotation region, thereby increasing the variation in the engine speed. Air compressor 209, 215
The intake flow rate and the supercharging pressure are controlled by reducing the fluctuation range of the rotation speed. In the high-speed rotation range, the air compressors 209, 2
15 is protected from excessive high-speed rotation.

As is well known, the output and the torque of the engine are increased by supercharging, so that the engine can be used in a low rotational speed range with good fuel efficiency by increasing the gear ratio of the vehicle, and is compared with a large displacement engine which is not supercharged. As a result, pump loss and mechanical loss are small, so fuel efficiency is improved.

[0008]

However, since both the mechanical supercharger 201 and the supercharger 203 are constructed by using belt-type continuously variable transmissions 205 and 211, the width, height, Each dimension of the length is larger.

Therefore, regardless of whether the engine is installed vertically or horizontally, interference with other accessories such as an alternator or a power steering pump occurs, and the arrangement location is limited. In addition, the front projection area of the vehicle increases, and the fuel efficiency decreases.

[0010] Further, it is difficult to sufficiently control the supercharging flow rate and the supercharging pressure of the air compressors 209 and 215 by the rotation speed control by the belt type continuously variable transmissions 205 and 211.
For example, the air compressor 20
When the shift characteristics are adjusted so as to protect the engine 9 and 215, as shown by the graph 217 and the hatched portion 219 in FIG. If the shift characteristic is adjusted so that a sufficient intake flow rate can be obtained in the medium / low speed rotation range, the protection of the air compressors 209 and 215 in the high speed rotation range becomes insufficient.

Further, it is impossible to finely control the supercharging air flow rate and the supercharging pressure of the air compressors 209 and 215 according to the running state of the vehicle, road surface conditions, and the like.

In the belt type continuously variable transmissions 205 and 211 which rely on friction for power transmission, the friction between the belt and the pulley is large and the power transmission efficiency is low, so that the fuel efficiency is reduced accordingly.

As described above, since there are many factors that lower the fuel efficiency, the effect of improving the fuel efficiency by supercharging the engine is insufficient.

Since the problem of air pollution due to exhaust gas is exacerbated with a decrease in fuel consumption (increase in fuel consumption), high-power engines with high fuel consumption and exhaust gas are used in countries and regions where exhaust gas regulations are strict. Not welcome.

A mechanical supercharger 201 and a supercharger 203
Is complicated in structure and costly because the belt-type continuously variable transmissions 205 and 211 are used.

When the belt-type continuously variable transmissions 205 and 211 are used, one of the bearings for supporting the speed change pulley needs to be large, and the cost increases accordingly.

Therefore, the present invention is compact and has no restriction on the arrangement location, the front projection area can be reduced, and the supercharged air flow rate can be reduced in accordance with the running state of the vehicle and the operating state of the engine. Can be controlled,
An object of the present invention is to provide a mechanical supercharger which is excellent in power transmission efficiency, can greatly improve fuel efficiency and can reduce exhaust gas, has a simple structure, and is low in cost.

[0018]

According to a first aspect of the present invention, there is provided a mechanical supercharger in which an air compressor driven by a driving force of an engine, a motor driving the air compressor, and a rotational speed of the engine satisfy a predetermined value. When it exceeds, the motor is stopped, and when the engine speed falls below a predetermined value, the controller drives the air compressor by the motor, and when the engine speed falls below the predetermined value, the air compressor is disconnected from the engine side. And separating means.

As described above, in the mechanical supercharger of the present invention, the air compressor is driven by the engine when the engine speed exceeds a predetermined value, and the air compressor is driven when the engine speed becomes lower than the predetermined value. Unlike the conventional examples shown in FIGS. 6 and 7, the intake flow rate of the air compressor can be finely controlled according to the running state of the vehicle by controlling the rotation speed of the motor. It is possible.

In particular, the air compressor is driven by a motor in a middle / low speed rotation range (rotation speed less than a predetermined value) in which the amount of exhaust gas and pollutants increase due to a decrease in fuel consumption, and a sufficient supercharged air flow rate and excess Since fuel pressure is obtained, fuel efficiency is improved and exhaust gas is purified accordingly.

Also, unlike the prior art, in which the air compressor is driven over the entire range of engine speed, the output and torque of the engine are insufficient in the middle and low speed rotation ranges. By driving the motor in the low-speed rotation range, the shortage of the intake air flow rate and the supercharging pressure is eliminated, and the engine can obtain a sufficient output and torque.

In the high-speed rotation range where the engine speed exceeds a predetermined value, the required intake air flow also increases. However, in this high-speed rotation range, the engine drives the air compressor. For example, when an electric motor is used, the load on the battery is reduced, and the fuel efficiency is improved.

Further, the mechanical supercharger of the present invention does not use a belt-type continuously variable transmission, unlike the conventional examples, so that the width, height and length are small and compact. .

Further, since a small motor can be used as described above, the mechanical supercharger becomes more compact.

[0025] Therefore, it is possible to relieve the restriction of the arrangement place due to the interference with other auxiliary machines, to reduce the projected area on the front side, and to greatly improve the fuel efficiency.

Further, the mechanical supercharger of the present invention does not use a belt-type continuously variable transmission having a low power transmission efficiency, so that the fuel efficiency is improved accordingly.

For the above reasons, the effect of improving fuel efficiency by supercharging the engine can be sufficiently obtained.

Further, the structure is simple because a belt-type continuously variable transmission is not used, and the problem of an increase in the size of bearings due to the use of a speed change pulley is solved, so that the cost is greatly reduced. You.

Further, in the vehicle, as described above, the use of the mechanical supercharger of the present invention for greatly improving fuel efficiency, reducing the amount of exhaust gas, and purifying the exhaust gas makes it possible to use the vehicle in a country where exhaust gas regulations are strict. Even in regions, vehicles with high-power engines can be used without violating this regulation.

A mechanical supercharger according to a second aspect of the present invention is the mechanical supercharger according to the first aspect, wherein the disconnecting means is disconnected in an engine speed range below a predetermined value, and the motor is turned off. It is a one-way clutch that is disengaged from the engine side, and has the same effect as the configuration of the first aspect.

In addition, the use of a one-way clutch as the disconnecting means allows the air compressor and the motor
This mechanical supercharger, which is composed of a rotor and a one-way clutch, has a simpler structure and lower cost.

A mechanical supercharger according to a third aspect is the mechanical supercharger according to the second aspect, wherein the controller provides a driving force to the motor in an engine speed range exceeding a predetermined value. The present invention is characterized in that the engine is provided and rotated to reduce the load on the engine, and an effect equivalent to that of the second aspect is obtained.

In addition, in an engine speed range exceeding a predetermined value (a speed range in which the air compressor is driven by the engine), the motor is rotated by applying a driving force, so that the load on the engine is reduced accordingly. Thus, a decrease in fuel efficiency is prevented.

A mechanical supercharger according to a fourth aspect is the mechanical supercharger according to any one of the first to third aspects, wherein the motor and the air compressor are coaxially arranged. And the same effects as those of the first to third aspects are obtained.

In addition, by arranging the motor and the air compressor coaxially, the mechanical supercharger has a smaller size in the radial direction and is more compact. Can be improved.

A mechanical supercharger according to a fifth aspect is the mechanical supercharger according to the fourth aspect, wherein the motor and the air compressor arranged coaxially are arranged in parallel with the engine.
The engine is connected to the engine via a belt transmission mechanism or a chain transmission mechanism, and the same effects as those of the fourth aspect are obtained.

In addition to this, the motor and the air compressor arranged coaxially are arranged in parallel with the engine and connected to the engine via a belt transmission mechanism or a chain transmission mechanism, so that a horizontally mounted engine is provided. In this case, for example, it is possible to arrange the mechanical supercharger behind the engine, so that the front projected area is reduced accordingly and the fuel efficiency is improved.

The belt transmission mechanism or the chain transmission mechanism may connect the engine and the motor, or may connect the engine and the air compressor.

A mechanical supercharger according to a sixth aspect is the mechanical supercharger according to the fourth aspect, wherein the motor and the air compressor disposed coaxially connect the respective shafts and the casing together. In this case, the same effects as those of the fourth aspect are obtained.

In addition, the unitized motor and air compressor can be easily assembled and removed, and their operation costs can be reduced.

Also, the unitization of the motor and the air compressor makes this mechanical supercharger more compact.
Since it is easy to arrange the engine in a narrow space around the engine, the front projected area can be reduced accordingly, and the fuel efficiency can be improved.

A mechanical supercharger according to a seventh aspect is the mechanical supercharger according to any one of the first to sixth aspects, wherein the motor is an electric motor, When the vehicle is braked, the controller stops supplying power to the electric motor and charges the battery with the electric power generated by the electric motor. Get the effect.

In addition, the use of an electric motor as the motor makes it possible to charge the battery with the electric power generated by the electric motor during braking of the vehicle, thus recovering energy. As a result, fuel efficiency improves accordingly.

The mechanical supercharger according to claim 8 is the mechanical supercharger according to any one of claims 1 to 7, wherein the controller comprises a crankshaft, a motor, The engine speed is detected by a part or all of a speed sensor for detecting each speed of an air compressor and an accelerator angle sensor for detecting an accelerator angle. When the engine speed exceeds a predetermined value, the motor is stopped. When the engine speed falls below a predetermined value, the motor stops.
The same effect as the configuration of the first to seventh aspects is obtained by driving the data.

[0045]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. This embodiment is described in claims 1, 2, 3,
4, 5, 6, 7, 8 are provided. The mechanical supercharger 1 according to this embodiment is used for an engine 3 that is horizontally arranged on a vehicle. The left and right directions in FIGS. 1 and 2 are the left and right directions of the vehicle, and the upper side in FIGS. 1 and 2 and the right side in FIG. 3 correspond to the front of the vehicle. In addition, members and the like without reference numerals are not shown.

As shown in FIGS. 1 and 2, the mechanical supercharger 1 of this embodiment comprises a centrifugal air compressor 5, a planetary
Gear type speed increasing mechanism 7, DC motor 9 (Motor: Electric motor
), Belt transmission mechanism 11, one-way clutch 13
(Separating means), a rotation speed sensor 17 of the crankshaft 15, a rotation speed sensor 19 of the DC motor 9 and the air compressor 5, an accelerator angle sensor 23 for detecting an angle of the accelerator 21, a controller 25, a battery 27, and the like. It is configured.

As shown in FIG. 1, the engine 3 is a large-displacement V-type six-cylinder engine having a pair of exhaust manifolds 29, 29 and an intake manifold 31.

As shown in FIG. 2, the air compressor 5 comprises an impeller 35 fixed to an impeller shaft 33 and a compressor casing 37. As will be described later, the impeller 35 (impeller shaft 33) 3 or a rotary motor 9 driven by the DC motor 9 to suck the intake air 39 from the suction port 41 of the compressor casing 37 and pressurize the supercharged air 45 and discharge the supercharged air 45 discharged from the discharge port 43 as shown in FIG. To the respective cylinders 47 from the compressor 31 to supercharge the engine 3.

As shown in FIG. 2, the speed increasing mechanism 7 includes an internal gear 49, a pinion gear 51, and a sun gear 53.

The internal gear 49 is formed integrally with the input shaft 55, and the sun gear 53 is formed on the left end side of the impeller shaft 33 of the air compressor 5. or,
The pinion gear 51 is a flange member 5 on the casing 57 side.
9 on a pinion shaft 61 supported by
3 is supported.

The impeller shaft 33 has a sliding bearing 6
It is supported by bearing holder 69 via 5, 67. The bearing holder 69 is pressed into the flange member 59 and is supported. Further, a nozzle 71 and an oil passage 73 are provided on the outer circumference of the slide bearings 65 and 67 by an external oil pump.
An oil film damper is formed by pressurized oil given through the slide bearings 65 and 67.
Supports the impeller shaft 33 while absorbing vibration through the oil film damper.

The casing 57 of the speed increasing mechanism 7 has a circumferential groove 7
It is fixed to the compressor casing 37 of the air compressor 5 together with the flange member 59 by a connecting member 77 and a bolt 79 that engage with the compressor 5.

The right end of the rotor shaft 81 of the DC motor 9 is connected to the input shaft 55 of the speed increasing mechanism 7. The casing 83 is fixed to the casing 57 of the speed increasing mechanism 7 by a bolt 85.

As described above, the air compressor 5, the speed increasing mechanism 7, and the DC motor 9 are coaxially arranged in this order, the respective shafts 33, 81 are connected, and the respective casings 37, 57, 83 are connected. It is fixed and unitized.

The unitized air compressor 5, the speed increasing mechanism 7, and the DC motor 9 are arranged at the rear side of the engine 3 in parallel with the engine 3, as shown in FIGS.

As shown in FIG. 3, a crankshaft pulley 87 is fixed to the crankshaft 15 of the engine 3, and the pulley 87 is connected via a belt 89 to an air-cooling fan pulley of the engine 3. The drive 91 is connected to an integral pulley 93, 95 connected to an AC generator and an air conditioner pump, respectively, and to a pulley 97 of a power steering pump. Accordingly, auxiliary equipment such as an air cooling fan, an AC generator, an air conditioner pump, and a power steering pump are rotationally driven.

The tension of the belt 89 is maintained at an appropriate level by the three tension pulleys 99, 101 and 103, and slippage with the pulleys 87, 91, 93 and 97 is prevented. ing.

As shown in FIGS. 1 and 3, the belt transmission mechanism 11 includes a crankshaft pulley 87, a motor pulley 105, and a belt 107 connecting these. As shown in FIG. 2, the motor pulley 105 is a low load of the DC motor 9.
The one-way clutch 13 and the bearings 109 and 109 are connected to the left end side of the
It is fixed at 11.

The one-way clutch 13 is connected when the rotation speed of the engine 3 (motor pulley 105) exceeds the rotation speed of the DC motor 9, and the driving force of the engine 3 is changed to DC.
It is sent from the motor 9 to the air compressor 5 via the speed increasing mechanism 7.

The rotation speed of the DC motor 9 is
When the rotation speed exceeds the side rotation speed, the one-way clutch 13 is disengaged to disconnect the DC motor 9 from the engine 3 so that the air compressor 5 is driven only by the DC motor 9.

The rotation speed sensor 17 is connected to the crankshaft 15
The rotation speed sensor 19 detects the rotation speed of the DC motor 9 or the air compressor 5, and the accelerator angle sensor 23 detects the angle of the accelerator 21 and sends it to the controller 25.

The controller 25 includes sensors 17, 19,
The number of rotations of the engine 3 is calculated from each signal of the engine 23, and the load state of the engine 3 is detected based on the angle signal of the accelerator angle sensor 23.

The controller 25 has an engine speed r1 (a predetermined engine speed: 1) for switching the drive source of the air compressor 5 between the engine 3 and the DC motor 9.
When the engine speed is lower than r1 in the middle / low speed rotation range, the controller 25 transfers the battery speed from the battery 27 to the DC motor 9. Power is supplied to drive the air compressor 5 by motor. As described above, during this motor driving, the DC motor 9 is disconnected from the engine 3 by the one-way clutch 13.

When the engine speed exceeds r1 and enters the high-speed rotation range, the controller 25 stops supplying power to the DC motor 9. At this time, the driving force of the engine 3 is transmitted from the one-way clutch 13 via the DC motor 9 to the speed increasing mechanism 7.
Is transmitted to the air compressor 5 and the air compressor 5
Is engine driven.

The controller 25 supplies the electric power of the battery 27 to the DC motor 9 while the air compressor 5 is being driven by the engine 3 and rotates the DC motor 9 at an appropriate speed.
The load of the C motor 9 is not applied to the engine 3 to prevent a decrease in fuel efficiency.

The controller 25 stops supplying power to the DC motor 9 during braking of the vehicle, and controls the DC power during braking.
The battery 27 is charged with electric power generated by the rotation of the motor 9.

The driving force of the engine 3 or the DC motor 9 is as follows.
Input from the internal gear 49 to the speed increasing mechanism 7, the speed is increased from the pinion gear 51 via the sun gear 53, and the impeller 3 of the air compressor 5 is transmitted via the impeller shaft 33.
5 is driven to rotate.

FIG. 4 is a characteristic diagram showing a change in the number of rotations rc of the air compressor 5 with respect to a change in the number of rotations r of the engine 3. FIG. FIG. 4 is a characteristic diagram showing changes in

In the mechanical supercharger 1, as described above, the air compressor 5 is driven by the engine 3 in a high-speed rotation range where the engine speed r exceeds r1, as indicated by an arrow 115 in a graph 113 of FIG. , Air compressor 5
Are driven at a high rotational speed rc.

Therefore, the arrow 119 in the graph 117 of FIG.
As shown in FIG. 7, the air compressor 5 can obtain a sufficient supercharged air flow rate Q, and the engine 3 can obtain a high output and a large torque.

In the middle / low speed range where the engine speed r is equal to or lower than r1, the DC compressor 9 drives the air compressor 5 at the required speed rc as indicated by an arrow 121 in FIG.

Therefore, as indicated by the arrow 123 in FIG.
The air compressor 5 can obtain a required supercharged air flow rate Q even in a middle / low speed rotation range, and the engine 3 can obtain a sufficient output and torque.

In the case of motor driving, the rotation speed of the air compressor 5 can be precisely controlled through the DC motor 9, so that the air compressor 5 can be controlled as shown by the broken lines in the arrows 121 and 123. Rotation speed rc and supercharged air flow rate Q
And the output and torque of the engine 3 can be arbitrarily adjusted according to the running conditions of the vehicle, road surface conditions, and the like.

A graph 117 of FIG. 5 and a graph 21 of the conventional example
7 and 219, the mechanical supercharger 1
A sufficient supercharged air flow rate Q can be obtained through the high-speed rotation range and the middle and low-speed rotation ranges, and the engine 3 can obtain sufficient output and torque.

Thus, the mechanical supercharger 1 is configured.

As described above, in the mechanical supercharger 1, the air compressor 5 is driven by the engine when the engine 3 is in the high-speed rotation range, and is driven by the motor in the middle and low-speed rotation range. Unlike the conventional example in which the output and torque of the engine are insufficient in the engine speed range, the engine 3 generates a sufficient output and torque in a wide rotation speed range including the middle and low speed rotation ranges.

As described above, a desired supercharging characteristic can be obtained in the entire range of the engine speed from the high speed range to the low speed range.

In the middle / low speed rotation range, the supercharging air flow rate Q and the supercharging pressure of the air compressor 5 are finely controlled by controlling the rotation speed of the DC motor 9 in accordance with the running conditions of the vehicle and the road surface conditions. Because it can be adjusted, driving performance, maneuverability, running performance, etc. are greatly improved.

Further, the DC motor 9 is advantageous in that the number of revolutions can be easily controlled as compared with the AC motor.

In the high-speed rotation range of the engine 3, the intake air flow required for the air compressor 5 also increases, but in the high-speed rotation range, the engine 3 drives the air compressor 5. For example, 5 kw to 7.5 kw
It is possible to use a small-sized motor having a small capacity, which reduces the load on the battery 27 and improves the fuel efficiency.

Further, a sufficient supercharging air flow rate Q and a supercharging pressure can be obtained even in a middle / low speed rotation range in which the pollutants in the exhaust gas increase due to a decrease in the fuel efficiency, so that the fuel efficiency is improved and the exhaust gas is purified accordingly. You.

Further, since a belt-type continuously variable transmission having poor power transmission efficiency is not used, fuel efficiency is improved accordingly.

Further, the air compressor 5, the speed increasing mechanism 7 and the DC motor 9 which are coaxially arranged are connected to the engine 3 via a belt transmission mechanism 11, and are arranged in parallel behind the engine 3 so that the engine 3 In the case of such a horizontally mounted engine, the projected area of the front of the engine including the auxiliary devices is reduced accordingly, and the fuel efficiency is improved.

Further, since the DC motor 9 rotates with the battery power during the operation of the engine, the load on the engine 3 is reduced correspondingly, and a decrease in fuel efficiency is prevented.

Since the battery 27 is charged with the electric power generated by the DC motor 9 during braking to recover energy.
That improves fuel economy.

As described above, since fuel efficiency is greatly improved and exhaust gas contamination is reduced accordingly, even in a country or a region where emission regulations are strict, vehicles equipped with a high-power engine can be installed without violating the regulations. Can be used.

Further, unlike each conventional example, the mechanical supercharger 1
Does not use a belt-type continuously variable transmission, so that the width, height, and length dimensions are reduced accordingly, and the size is reduced.

As described above, the small-capacity DC motor 9 has extremely small width, height and length dimensions of 12 cm each, making the mechanical supercharger 1 more compact.

The unitized air compressor 5, the speed increasing mechanism 7, and the DC motor 9 can be easily attached to and detached from the engine, so that their working costs can be reduced, and the unitization can be achieved. More compact,
It becomes easy to arrange in a narrow space around the engine 3.

Further, the use of a one-way clutch as a disconnecting means for disconnecting the air compressor 5 and the DC motor 9 from the engine 3 simplifies the structure of the mechanical supercharger 1, makes it more compact, and reduces the Cost.

The mechanically structured supercharger 1 thus compacted prevents interference with other auxiliary equipment such as an air cooling fan, an AC generator, a pump for an air conditioner, and a pump for power steering. Thus, it is free from the restriction on the arrangement place due to the interference with other auxiliary machines.

Further, by making the mechanical supercharger 1 compact, the projected area of the front of the engine including accessories is further reduced, fuel efficiency is improved, and the amount of exhaust gas and dirt are reduced.

Further, the mechanical supercharger 1 has a simple structure because it does not use a belt-type continuously variable transmission, and does not have the problem of increasing the size of bearings due to the use of a speed change pulley. Significant cost reduction.

In the present invention, the air compressor is not limited to a centrifugal compressor, but may be, for example, a roots compressor.
Positive displacement compressors such as screw compressors and vane pumps and other types of compressors may be used.

The motor for driving the air compressor is not limited to the electric motor, but may be, for example, a hydraulic motor or another rotary driving force source.

The electric motor is not limited to a DC motor,
An AC motor may be used.

The disconnecting means for disconnecting the air compressor from the engine at an engine speed equal to or lower than a predetermined value is not limited to a one-way clutch. For example, a clutch that can be opened and closed may be used, and when the engine speed falls below a predetermined value, the clutch may be released by a controller to disconnect the air compressor from the engine.

[0098]

As described above, the mechanical supercharger of the present invention is constructed such that the air compressor is driven by the motor when the engine speed falls below a predetermined value. By controlling the rotation speed of the motor, the intake air flow rate of the air compressor can be finely controlled in accordance with the running state of the vehicle, road surface conditions, and the like. The shortage of the boost pressure is eliminated.

Further, the air compressor is driven by the motor in a middle / low speed rotation range (rotation speed less than a predetermined value) in which pollutants in the exhaust gas increase due to a decrease in fuel efficiency, and a sufficient supercharging air flow and supercharging are performed. Since pressure and pressure are obtained, fuel efficiency is improved and exhaust gas is purified accordingly.

In the high-speed rotation range of the engine where the required intake air flow increases, the engine drives the air compressor. Therefore, a small-sized motor having a small capacity can be used as the motor. When the electric motor is used, the load on the battery is reduced, and the fuel efficiency is improved.

Further, since the mechanical supercharger of the present invention does not use a belt-type continuously variable transmission having a low power transmission efficiency, the fuel efficiency is improved accordingly.

Further, the mechanical supercharger of the present invention does not use a belt-type continuously variable transmission unlike the conventional examples, so that the width, height, and length dimensions are reduced accordingly, and Since a small motor can be used as in the above, the mechanical supercharger can be made compact.

The mechanical supercharger thus made compact is free from the restriction of the arrangement place due to the interference with other auxiliary machines, and has a small front projection area, thereby further improving fuel efficiency.

Also, since the belt-type continuously variable transmission is not used in the vehicle, the structure is simple, and the problem of increasing the size of the bearing due to the use of the speed change pulley is solved, so that the cost is greatly reduced. Is done.

Further, if the mechanical supercharger of the present invention for purifying exhaust gas by greatly improving fuel efficiency as described above is used,
Even in countries and regions where emission regulations are strict, vehicles equipped with high-power engines can be used without violating the regulations.

The mechanical supercharger according to the second aspect has the same effect as the configuration according to the first aspect, and is constituted by an air compressor, a motor and a one-way clutch by using a one-way clutch for the disconnecting means. The resulting mechanical supercharger is simpler in structure, more compact, and lower in cost.

The mechanical supercharger according to the third aspect has the same effect as the configuration according to the second aspect, and provides a driving force to the motor to rotate the motor in a rotation speed range where the air compressor is driven by the engine. Since the load on the engine is reduced, a decrease in fuel efficiency is prevented.

According to the mechanical supercharger of the fourth aspect, the same effects as those of the first to third aspects are obtained, and the motor and the air compressor are arranged coaxially, so that the mechanical supercharger is provided. Has a smaller size in the radial direction, which makes it more compact, reduces the projected area of the front of the vehicle, and improves fuel efficiency.

According to the mechanical supercharger of the fifth aspect, the same effect as that of the configuration of the fourth aspect is obtained, and the motor and the air compressor are arranged coaxially and in parallel with the engine. Alternatively, since the engine is connected to the engine via a chain transmission mechanism, in the case of a horizontally mounted engine, the mechanical supercharger can be arranged at the rear of the engine, the front projected area is reduced accordingly, and fuel efficiency is improved. I do.

According to the mechanical supercharger of the sixth aspect, the same effect as the configuration of the fourth aspect can be obtained, and the unitized motor and air compressor can reduce the assembly and removal work costs, and Furthermore, since it becomes more compact and can be easily arranged in a narrow space around the engine, the front projected area is correspondingly smaller, and the fuel efficiency is improved.

The mechanical supercharger according to the seventh aspect has the same effects as those of the first to sixth aspects, and uses an electric motor for the motor, so that the electric motor is electrically operated when the vehicle is braked. Mo
The battery can be charged by the battery and energy can be recovered, thereby improving fuel efficiency.

The mechanical supercharger according to the eighth aspect has the same effects as those of the first to seventh aspects.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 shows a DC unitized in the embodiment of FIG.
It is sectional drawing which shows a motor, a speed increasing mechanism, and an air compressor.

FIG. 3 is a side view of the embodiment of FIG. 1 as viewed from a cooling fan side of the engine.

FIG. 4 is a graph showing a change in the number of revolutions of the air compressor with respect to the number of revolutions of the engine in the embodiment of FIG. 1;

FIG. 5 is a graph comparing the change in the supercharged air flow rate with respect to the engine speed between the embodiment of FIG. 1 and the conventional example.

FIG. 6 is a sectional view of a conventional example.

FIG. 7 is a configuration diagram of another conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Mechanical supercharger 3 Engine 5 Centrifugal air compressor 9 DC motor (Motor: Electric motor) 11 Belt transmission mechanism 13 One-way clutch (disconnection means) 15 Crankshaft 17 Crankshaft rotation speed sensor 19 DC motor 9 and rotation speed sensor of air compressor 5 23 Accelerator angle sensor 25 Controller 27 Battery 37 Casing of air compressor 5 83 Casing of DC motor 9

Claims (8)

[Claims] An air compressor driven by a driving force of an engine, a motor for driving the air compressor, and when the engine speed exceeds a predetermined value, the motor is stopped, and the engine speed is set to a predetermined value. A mechanical supercharger comprising: a controller for driving an air compressor by a motor when the rotation speed of the engine becomes equal to or less than a predetermined value; and separating means for separating the air compressor from the engine when the rotation speed of the engine becomes equal to or less than a predetermined value. Machine. 2. The invention according to claim 1, wherein the disconnecting means is a one-way clutch that is disconnected in an engine speed range equal to or lower than a predetermined value and disconnects the motor from the engine side. Mechanical supercharger. 3. The invention according to claim 2, wherein the controller reduces the load on the engine by applying a driving force to the motor to rotate the motor in an engine speed range exceeding a predetermined value. Features a mechanical supercharger. 4. The mechanical supercharger according to claim 1, wherein the motor and the air compressor are arranged coaxially. 5. The invention according to claim 4, wherein the motor and the air compressor are coaxially arranged, and the motor and the air compressor are arranged in parallel with the engine, and the engine and the air compressor are arranged via a belt transmission mechanism or a chain transmission mechanism. A mechanical supercharger, which is connected to a turbocharger. 6. The mechanical type according to claim 4, wherein the motor and the air compressor which are coaxially arranged are unitized by connecting their shafts and casing to each other. Supercharger. 7. The vehicle according to claim 1, wherein the motor is an electric motor, and the mechanical supercharger is mounted on a vehicle. A mechanical supercharger in which the controller stops supplying power to the electric motor and charges the battery with electric power generated by the electric motor during braking. 8. The invention according to claim 1, wherein the controller is configured to detect a rotational speed of each of a crankshaft, a motor, and an air compressor. A mechanical supercharger for detecting an engine speed with a part or all of an accelerator angle sensor for detecting an accelerator angle.