JP2902180B2 - Control device for mechanical supercharger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a mechanical supercharger mechanically driven by an engine output.

[0002]

2. Description of the Related Art In general, a mechanical supercharger mechanically driven by an engine output is provided with a clutch in a power transmission path between an engine output shaft and a supercharger, and according to an operation state of the engine. The power transmission path is interrupted by connecting (ON) or disconnecting (OFF) the clutch (see Japanese Patent Application Laid-Open No. 1-240734).

[0003] More specifically, the power transmission path of a mechanical supercharger includes a crank side pulley attached to an engine output shaft and a supercharger side pull attached to an input shaft of the supercharger. And an endless belt wound around these two pulleys, wherein the clutch is interposed between the input shaft of the supercharger and the supercharger-side pulley, For example, in a low load region where a large output is not required, the clutch is turned off.
As a result, the power transmission path is disconnected (the turbocharger enters a free state).

[0004] When an attempt is made to obtain a high supercharging pressure with a mechanical supercharger, a crank-side pull with respect to a turbocharger-side pulley is required.
In this case, a large pulley ratio (high pulley ratio) is set as the pulley ratio of the clutch.
The torque shock accompanying OFF becomes large.

[0005] In order to solve the problem of torque shock accompanying the high supercharging pressure, a transmission mechanism is provided in the power transmission path, and a low pulley ratio (low speed gear) is set before setting a high pulley ratio. ) May be used to reduce the shock associated with turning on and off the clutch. According to this, it is possible to obtain a high supercharging pressure based on the high pulley ratio, but it is possible to expand a region where the supercharger is in a free state. Feeder free
(Because it is not necessary to narrow the area), there is an advantage that deterioration of the fuel consumption rate can be avoided.

[0006]

Another problem associated with increasing the supercharging pressure is that the load on the engine or the supercharger increases. That is, for example, when the supercharger is rotated at a high speed to obtain a high supercharging pressure, heat generated by the supercharger (heat generated due to sliding of a rotor in a casing of the supercharger, etc.) is generated. Are more susceptible to thermal damage. Further, in the engine, the heat load inside the engine becomes large due to the high supercharging pressure, and for example, the valve bridge is easily damaged. For this reason, when traveling in an environment where the outside air temperature is extremely high, the supercharger may be damaged or the engine may be damaged due to the high intake air temperature.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a control device for a mechanical supercharger that prevents damage to a supercharger or an engine when a high supercharging pressure is set. .

[0008]

Means for Solving the Problems In order to achieve the above technical objects, the present invention has the following configuration.

According to a first aspect of the present invention , a path disconnecting clutch is provided in a power transmission path between an engine output shaft and a supercharger, and the path disconnecting clutch is turned on and off in accordance with an operation state of the engine. On the premise of a control device for a mechanical supercharger that interrupts the power transmission path, the power transmission path is disposed in a power transmission path between an engine output shaft and a supercharger, and at least a low speed stage and a high speed stage 2
A transmission mechanism having a first gear, an engine load detecting means for detecting an engine load, receiving a signal from the engine load detecting means, and setting the low speed when the engine load is in a low load region; Shift control means for setting the high-speed stage when the engine load is in a high load region;
Damage factor detecting means for detecting the occurrence of a factor directly related to engine or turbocharger damage, and receiving a signal from the damage factor means, and when a factor directly related to engine or turbocharger damage is developed, the high-speed Receiving a signal from the high-speed step prohibiting means for prohibiting the setting of the step and the damage factor means,
And a low-load region enlarging means for enlarging the low-load region where the low-speed stage is set to a high-load side when a factor directly causing damage to the engine or the supercharger appears.

According to a second aspect of the present invention, a disconnection clutch is provided in a power transmission path between an engine output shaft and a supercharger, and the engine is operated in an operating state. In response, the path disconnection clutch is turned ON and OFF, and the control device of the mechanical supercharger is configured to disconnect and connect the power transmission path.
A transmission mechanism disposed on a power transmission path between the engine output shaft and the supercharger, the transmission mechanism having at least two speed stages, a low speed stage and a high speed stage, and an engine load detecting unit for detecting an engine load; A shift control unit that receives a signal from the engine load detection unit, sets the low speed stage when the engine load is in a low load region, and sets the high speed stage when the engine load is in a high load region; Power transmission detecting means for detecting intermittent power transmission paths between the driving wheels, and receiving a signal from the power transmission detecting means, when the power transmission path between the engine and the driving wheels is disconnected, And a high-speed gear setting prohibiting unit for prohibiting the setting of the high-speed gear.

[0011]

In accordance with the action present invention of the first invention, for example because the supercharger is prohibited the use of the high speed stage when the traveling high in the outside air temperature operating under low speed stage, due to the high intake air temperature It is possible to prevent the overheating of the turbocharger or the temperature rise exceeding the limit of the internal temperature of the engine. Furthermore, in the present invention,
While the use of the high-speed stage is prohibited, the range in which the low-speed stage is used is expanded to the high load side, so it is possible to compensate to some extent even in the low-speed stage for the output reduction due to the prohibition of the use of the high-speed stage in the high load region Becomes

According acting on the second aspect of the second invention, the accelerator operation not related to travel, that is Le - accompanied by sequencing, the operation of the turbocharger under high speed stage, to repeat its frequent stop It is possible to prevent the turbocharger from being damaged.

[0013]

Embodiments of the present invention will be described below with reference to the accompanying drawings. First Embodiment (FIGS. 1 to 7) In FIGS. 1 and 2, 1 is an engine, and an engine 1 is
A so-called V-type 6 having left and right bank portions 2L, 2R forming a V-shape with each other (bank angle 90 °), and three cylinders 3 arranged in series for each of the left and right bank portions 2L, 2R, respectively. It is a cylinder engine.

In each of the cylinders 3, a combustion chamber 6 is formed by a piston 5 inserted into a cylinder 4, and the combustion chamber 6 is of a pent-roof type. An intake passage 7 is connected to the combustion chamber 6. And an exhaust port 10 to which an exhaust passage 9 is connected. The piston 5 is linked to a crankshaft 11 via a connecting rod, and an engine output is taken out from the crankshaft 11.

The engine 1 includes a balancer shaft 12 which is disposed above the crankshaft 11 and which is disposed above the crankshaft 11.
Are connected via a pair of counter gears 13a and 13b so as to rotate synchronously with the crankshaft 11.

An intake valve 14 for opening and closing the intake port 8 is driven to open and close by an intake camshaft 15, and an exhaust valve 16 for opening and closing the exhaust port 10 is driven to be opened and closed by an exhaust camshaft 17. That is, the intake camshaft 15 and the exhaust camshaft 17 are provided with an intake pulley 18 and an exhaust pulley 19 at their shaft ends, respectively. Part 2L,
The intake valve 14 and the exhaust valve 16 are opened and closed at a predetermined timing in synchronization with the rotation of the crankshaft 11 by being linked to the crankshaft 11 via a common timing belt 20 common to the 2Rs (described in detail later). Is done.

As shown in FIG. 2, the intake camshaft 15 has a variable valve timing mechanism 21 (variable valve timing mechanism for intake valve) for changing the phase of the intake camshaft 15 with respect to the intake pulley 18. On the other hand, the exhaust camshaft 17 is provided with a variable valve timing mechanism 22 (variable valve timing mechanism for exhaust valve) for changing the phase of the exhaust camshaft 17 with respect to the exhaust pulley 19. Then, the intake valve 14 or the exhaust valve 16 is
The valve timing is changed according to the operating state. The two variable valve timing mechanisms 21 and 22 have the same configuration.
1 and 22 are conventionally known, and therefore detailed description thereof will be omitted. A spark plug (not shown) is arranged facing the combustion chamber 6.

In the intake passage 7, an air cleaner 23, an air flow meter 24, a throttle valve 25, a roots-type supercharger 26, and an interlock are sequentially arranged from the upstream side to the downstream side. A fuel tank 27, a surge tank 28, and a fuel injection valve (not shown). Further, a bypass passage 29 for bypassing the supercharger 26 is provided in the intake passage 7, and an electromagnetic opening / closing valve (bypass valve) 30 is interposed in the bypass passage 29 so that the supercharging pressure is set to a predetermined value. When this occurs, the on-off valve 30 is opened and relieved.

As shown in FIG. 1, the supercharger 26 has a V-bank central space 3 sandwiched between left and right bank portions 2L and 2R.
1 and above the turbocharger 26
A cooler 27 is provided. The engine 1 includes various accessories 32 to 36 driven by the driving force of the engine 1.
It has.

The arrangement of the accessories 32 to 36 will be described. Water pumps 32L and 32R for the banks 2L and 2R are provided at the base ends of the left and right banks 2L and 2R. An oil pump 33 is disposed at the lower end of the oil pump. An air conditioner compressor 34 is provided on one side of the engine 1, and an alternator 35 and a power steering pump 36 are provided on the other side.

Oil pump 33, air conditioner compressor
, Alternator 35, power steering pon
As shown in FIG. 1, a large-diameter pulley 40 and a small-diameter pulley 41 are attached to the shaft end of the crankshaft 11.
An oil pump 33, an air conditioner compressor 34, and the like via an accessory belt 42 wound around the large-diameter pulley 40.
The alternator 35 and the power steering pump 36 are driven. That is, the accessory belt 42 is wound around the large diameter pulley 40, the oil pump 33, the air conditioner compressor 34, the alternator 35, and the power steering pump 36.

Inlet pulley 1 for left and right banks 2L, 2R
8. Exhaust pulley 19, water pump 32L,
As shown in FIG. 1, the common timing belt 20 is wound around a small diameter pulley 41 of the crankshaft 11.
The common timing belt 20 is wound around the left and right water pumps 32L, 32R, and the left and right water pumps 32L, 32R, the intake valve 14, and the exhaust valve 16 are driven by the common timing belt 20. Here, FIG.
Numerals 43 to 46 denote idler pulleys, of which the idler pulley 45 is provided with an auto-tension mechanism.

Driving of the supercharger 26 (FIGS. 3 and 4) The supercharger 26 is configured to transmit power from the balancer shaft 12 via the first power transmission path 50 or the second power transmission path 51. Has become. Hereinafter, the power transmission path for the supercharger 26 will be described in detail.

First, as shown in FIG. 3, a direct connection pulley 52 fixed to the balancer shaft 12 and an electromagnetic clutch (path switching clutch) 53 are connected to the balancer shaft 12. And a detachable pulley 54 attached thereto, and the directly connected pulley 5 is provided.
2 and the disengagement pulley 54 have the same pulley diameter.

An input pulley (supercharger pulley) 56 is attached to an input shaft 26a of the supercharger 26 via an electromagnetic clutch (path disconnection clutch) 55.

An idler 57 is rotatably mounted on the engine 1 as shown in FIG. The idler 57 has a small-diameter pulley portion 57a and a large-diameter pulley portion 57b arranged in parallel in the axial direction, and the small-diameter pulley portion 57a is integrated with the idler main body 57c to form a large-diameter pulley. The rear portion 57b is connected to the idler main body 57c via a one-way clutch 58. The one-way clutch 58 has a large diameter
The engagement is performed when the rotation speed of the pulley portion 57b is higher than the rotation speed of the idler body 57c (the large diameter pulley portion 57b is integrated with the idler body 57c), and the rotation speed of the large diameter pulley portion 57b is reduced. It is released when the rotation speed of the idler main body 57c is lower than the rotation speed.

The pulley 5 directly connected to the balancer shaft 12
The first belt 60 is wound around the large diameter pulley portion 57b of the idler 57, while the engagement and disengagement 54 of the balancer shaft 12 and the small diameter pulley portion 57a of the idler 57 are provided.
And the input pulley 56 of the supercharger 26 have the second belt 6
1 is wound around to form the first power transmission path 50 and the second power transmission path 51.

The first power transmission path 50 (path switching clutch)
When the switch 53 is "OFF") pathway switching clutch 53 is turned "OFF" state, the first power transmission path 50 is formed. That is, the rotational force of the balancer shaft 12 is sequentially
The power is transmitted to the turbocharger pulley 56 via the reel 52, the first belt 60, the large-diameter pulley portion 57b of the idler 57, the one-way clutch 58, the small-diameter pulley portion 57a of the idler 57, and the second belt 61. You. According to the first power transmission path 50, the rotational force of the balancer shaft 12 is transmitted to the supercharger 26 via the large-diameter pulley portion 57b of the idler 57. The rotation speed of the supercharger 26 is lower than in the case of (1) (low speed mode).

The second power transmission path 51 (path switching clutch)
When the switch 53 is "ON") pathway switching clutch 53 is turned "ON" state, the second power transmission path 51 is formed. That is, the rotational force of the balancer shaft 12 is sequentially
The power is transmitted to the turbocharger pulley 56 via the first belt 54 and the second belt 61. According to the second power transmission path 51, the torque of the balancer shaft 12 is transmitted to the supercharger 26 without passing through the large-diameter pulley portion 57b of the idler 57. The rotation speed of the supercharger 26 is higher than that of the transmission path 50 (high-speed mode).
Incidentally, reference numeral 62 shown in FIG. 1 is a tensioner.

The rotational force of the balancer shaft 12 is also transmitted to the first belt 60 and the large-diameter pulley portion 57b of the idler 57 via the directly-connected pulley 52. The rotation speed of the pulley part 57b is
Since the rotation speed is lower than 7c, the one-way clutch 58 is released. Therefore, when the path switching clutch 53 is turned on, the first power transmission path 50 is disconnected by the one-way clutch 58.

Reference numeral 65 shown in FIG. 2 is a control unit, and the control unit 65 is constituted by, for example, a microcomputer.
M, RAM and the like. Control unit 65
, Signals from the sensors 66 to 68 are input. The sensor 66 detects the engine speed. The sensor 67 detects the opening of the throttle valve. The sensor 68 detects the temperature of the intake air.

The control unit 65 turns on and off the path switching clutch 53, the path disconnection clutch 55, and the open / close valve (bypass valve) 30.
A control signal is output, and the valve timing variable mechanism 2
A control signal is output to 1 and 22.

The contents of control of the path switching clutch 53 and the path disconnection clutch 55 will be described below. FIG. 5 shows a control map when the intake air temperature is equal to or lower than 40 ° C. When the temperature of the intake air is equal to or lower than a predetermined value (40 ° C. in this embodiment), the region I shown in FIG.
The following control is performed in each of the three areas, namely, the area III.

[0034]Region I (light load (below first predetermined value) and
Low, medium rotation) In this region I, the path interrupting clutch 55 is "OFF".
State and the supercharger 26 is powered by the first or second power
It is released from the connection with the transmission paths 50 and 51,
(Free mode). The path switching clutch 53
This is also set to the "OFF" state.

Region II (medium load (less than second predetermined value), medium
In this region II, the path switching clutch 53 is set to the “OF
F "state, the first power transmission path 50 is selected, and the path intermittent clutch 55 is set to the" ON "state, so that the rotational force of the balancer shaft 12 passes through the first power transmission path 50. It is transmitted to the supercharger 26 (low speed mode).

[0036]Region III (high load (from the second predetermined value)
Big)) In this region III, the path switching clutch 53
N ”state and the second power transmission path 51 is selected.
And the path interrupting clutch 55 is turned “ON”.
The rotational force of the balancer shaft 12 is
It is transmitted to the supercharger 26 via 51 (high-speed mode).

In the above control, the speed ratio (first power transmission path 50) set in the region II is different from the speed ratio in the region III.
The supercharger 26 has a speed ratio (low pulley ratio) such that the supercharger 26 is supercharged in a low speed state as compared with the case of (1). In other words, the speed ratio (the second power transmission path 51) selected in the region III is such that the supercharger 26 relatively supercharges at a high speed compared with the case of the region II. (High pulley ratio).

Control when the intake air temperature is higher than 40 ° C. When the temperature of the intake air is higher than a predetermined value (40 ° C. in this embodiment), the following control is performed in the region III. That is, when the intake air temperature is high,
In the region III, the "O"
N ”is prohibited. Then, the second predetermined value that partitions the area II is changed to a third predetermined value (greater than the second predetermined value). That is, this region expansion is performed, for example, by changing the set supercharging pressure of the relief valve 30 of the supercharger 26, and as shown in FIG. 5, the region II is expanded to the high load side. That is, when the engine load is equal to or less than the third predetermined value, the path switching clutch 53 is turned off.
Then, the first power transmission path 50 is selected (the low-speed mode of the supercharger 26 is selected). Conventionally,
Even when the intake air temperature is equal to or lower than 40 ° C., the supercharger 26 is driven by the first power transmission path 50 and the clutch 53 is kept “OFF” even in the region determined as the region III.

On the premise of the above, a specific description will be given based on the flowchart shown in FIG. Note that this flowchart is created focusing on only the engine load.

First, after reading the engine load and the like in step S1 (hereinafter, step numbers are denoted by adding "S"), in S2, the engine load is reduced to the first load.
It is determined whether or not the engine load is larger than the predetermined value. If the determination is NO, it is determined that the engine load is equal to or less than the first predetermined value, that is, the engine load is in the region I (see FIG. 5), and the process proceeds to S3. , The setting of the turbocharger 26 in the free mode (the path disconnection clutch 55 is set to “OFF”) is performed.

On the other hand, if it is determined YES in S2, it is determined that the engine load is larger than the first predetermined value, and the routine proceeds to S4, in which it is determined whether the engine load is equal to or less than the second predetermined value. When YES is determined in S4, it is determined that the engine load is equal to or less than the second predetermined value, that is, the engine load is in the region II (see FIG. 5). Setting the mode (the path switching clutch 53 is set to “OF
F ″) is performed.

On the other hand, if NO is determined in S4, it is determined that the engine load is larger than the second predetermined value, that is, the engine load is in the region III (see FIG. 5). It is determined whether or not the temperature is equal to or less than the value (40 ° C.).
Is determined, that is, when it is determined that the intake air temperature is 40 ° C. or lower, the routine proceeds to S7, where the supercharger 26 is set to the high speed mode (the path switching clutch 53 is set to “O”).
N ").

On the other hand, if it is determined NO in S6, that is, if it is determined that the intake air temperature is higher than 40 ° C., the routine proceeds to S8, where the supercharger 26 is set to the low speed mode, and The maximum value of the supercharging pressure used in the mode is increased to the third predetermined value.

While one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, but includes the following embodiments. (1) In step S6, instead of the intake air temperature,
It may be determined whether the knocking intensity is equal to or less than a predetermined value. That is, when the knocking intensity is larger than the predetermined value, it is determined that abnormal combustion has occurred, and by performing the processing after step S8, it is possible to prevent the engine from being damaged.

(2) In step S6, it may be determined whether the octane value of the fuel is larger than a predetermined value instead of the intake air temperature. That is, when the octane number of the fuel is small, knocking is likely to occur,
Therefore, assuming that the engine is likely to be damaged, it is possible to prevent the engine from being damaged by performing the processing after step S8.

(3) When the driver frequently performs the so-called lacing, in which the accelerator pedal is repeatedly depressed and released, the clutch 55 for path disconnection is set to the "OFF" state in the region II or III shown in FIG. The supercharger 26 may be in a free mode. According to this, the supercharger 26 is turned on and off with respect to the racing.
The damage of the supercharger 26 due to the repetition of the above can be prevented beforehand. In order to prevent damage due to this racing, for example, in the case of a manual transmission, the neutral or transmission clutch is set to “OF”.
F ", the turbocharger 26
May be a free mode. Similarly, in the case of a vehicle equipped with an automatic transmission, the supercharger 26 may be in the free mode when the N range, the P range, or the foot brake is depressed.

[0047]

As is apparent from the above description, according to the present invention, when setting a high supercharging pressure, damage to the supercharger or the engine can be prevented. According to the first invention, while the use of the high-speed stage is prohibited, the region in which the low-speed stage is used is expanded to the high load side. It can be supplemented to some extent in the steps.

[Brief description of the drawings]

FIG. 1 is a front view of a V-type engine to which an embodiment is applied.

FIG. 2 is an explanatory diagram showing an expansion of an intake system of the engine shown in FIG. 1;

FIG. 3 is a front view of a supercharger speed change mechanism applied to the embodiment;

FIG. 4 is a sectional view taken along the line IV-IV shown in FIG. 3;

FIG. 5 is a control map used for controlling the supercharger according to the embodiment.

FIG. 6 is a flowchart showing an example of supercharger control.

[Explanation of symbols]

 Reference Signs List 1 engine 5 piston 7 intake passage 11 crankshaft 12 balancer shaft 14 intake valve 25 throttle valve 26 mechanical supercharger 50 low-speed power transmission path 51 high-speed power transmission path 53 electromagnetic clutch (path switching clutch) 55 electromagnetic clutch ( (Clutch for interrupting path) 65 Control unit 66 Engine speed sensor 67 Throttle opening sensor 68 Intake air temperature sensor

Claims (5)

(57) [Claims] An on-off clutch is provided on a power transmission path between an engine output shaft and a supercharger, and the on-off clutch is turned on and off in accordance with an operation state of an engine.
In the control device for the mechanical supercharger, the power transmission path is intermittently provided, the control apparatus being disposed in the power transmission path between the engine output shaft and the supercharger, and having at least a low speed stage and a high speed stage. A speed change mechanism having two speed steps; an engine load detecting means for detecting an engine load; receiving a signal from the engine load detecting means, and setting the low speed step when the engine load is in a low load range. A shift control means for setting the high-speed stage when the engine load is in a high load range; a damage factor detecting means for detecting occurrence of a factor directly related to damage to the engine or the supercharger; and a signal from the damage factor means. When a factor that directly leads to damage to the engine or the turbocharger appears, a signal from the high-speed step prohibiting means for prohibiting the setting of the high-speed step and a signal from the damage factor means are received. And a low-load region enlarging means for enlarging the low-load region in which the low-speed stage is set to a high-load side when a factor directly associated with damage to the gin or the supercharger appears. Control means for mechanical supercharger. 2. The engine or the supercharger according to claim 1, wherein the damage factor detecting means detects a temperature of the engine or the supercharger when the temperature of the intake air is higher than a predetermined temperature based on a signal from a sensor for detecting the temperature of the intake air. A control means for a mechanical supercharger, characterized in that a factor directly leading to damage has occurred. 3. The engine or the turbocharger according to claim 1, wherein the damage factor detecting means is configured to detect the knocking generated by the engine when the magnitude of the knocking is greater than a predetermined value. A control means for a mechanical supercharger, characterized in that a factor directly leading to damage has occurred. 4. The engine according to claim 1, wherein when the octane value is smaller than a predetermined value based on a signal from a sensor for detecting the octane value of the fuel, the damage factor detecting means directly causes damage to the engine or the supercharger. Control means for a mechanical supercharger, characterized in that it has developed. 5. A path connecting / disconnecting clutch is provided in a power transmission path between an engine output shaft and a supercharger, and the path connecting / disconnecting clutch is turned on and off in accordance with an operation state of the engine.
In the control device for the mechanical supercharger, the power transmission path is intermittently provided, the control apparatus being disposed in the power transmission path between the engine output shaft and the supercharger, and having at least a low speed stage and a high speed stage. A speed change mechanism having two speed steps; an engine load detecting means for detecting an engine load; receiving a signal from the engine load detecting means, and setting the low speed step when the engine load is in a low load range. When the engine load is in the high load region, a shift control means for setting the high speed stage, a power transmission detection means for detecting the intermittent power transmission path between the engine and the drive wheels, and A high-speed gear setting prohibiting unit that prohibits at least the setting of the high-speed gear when the signal is received and the power transmission path between the engine and the drive wheels is disconnected. Controller of the mechanical supercharger to.