JPS5915626A - Mechanical supercharger of internal combustion engine - Google Patents

Abstract

PURPOSE:To prevent a transmission belt mechanism and a supercharger from being placed suddenly under load when supercharging operation is started by gradually placing the supercharger under load after rotating it in no-load condition. CONSTITUTION:During idle operation or light load operation, since opening of an intake air throttle valve 26 is small and a supercharge control valve 52 is in an opened position, intake air is sucked into an engine via a bypass duct 50. When the engine load is increased and the intake air throttle valve 26 reaches the first set opening, an electromagnetic clutch operates to put a vane pump 28 in turning. Since the above-mentioned supercharge control valve 52 is opened, no substantial load is placed on the vane pump 28. When the intake air throttle valve 26 exceeds the second set opening, said valve 52 is gradually closed and perfectly closed at last, and the bypass duct 50 is shut off, the vane pump 28 being operated in full-load condition.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a supercharging device for an internal combustion engine. The internal combustion engine supercharging devices used today are the so-called exhaust turbo supercharger, which is driven by a turbine that rotates by exhaust gas, and the so-called mechanical supercharger, which is driven by the engine crankshaft. Although these are broadly classified, the present invention relates more specifically to the latter type of supercharger.

In conventional mechanical supercharging systems, a supercharger such as a pen pong or Roots blower is installed in the engine's intake pipe upstream of the intake throttle υ valve, and the supercharger is operated via a transmission belt means. It is designed to be driven by the engine's crankshaft. If the supercharger is configured to be driven to rotate at all times, when the engine is under light load, the air pumped by the supercharger will be throttled by the intake throttle valve, resulting in a loss of power. Therefore, in order to rotate the supercharger only when supercharging is necessary, for example when the engine speed exceeds a predetermined value, an electromagnetic clutch is interposed between the transmission belt means and the supercharger. This makes it possible to intermittent human power to the supercharger. If the turbocharger and the air passage are in series, even if the clutch is disengaged at light load, the turbocharger will idle due to the intake air flow, so the idling turbocharger will cause airflow in the intake pipe. The resistance increases and the filling efficiency of the engine decreases. Therefore, a bypass pipe is installed in the intake pipe to bypass the supercharger, and a cutoff valve called a supercharging control valve is installed in this pipe. By opening this supercharging control valve, air is naturally drawn into the engine through the entire bypass pipe, and when the electromagnetic clutch is connected, the supercharging control valve is closed and the bypass pipe is cut off to perform supercharging. It is configured as follows.

However, in the conventional mechanical supercharging device mentioned above,
For example, in an engine with a displacement of 2.4 liters,
- The supercharger driving power reaches approximately 20 horsepower when the engine speed is 5000 rpm. For this reason, electromagnetic clutch?
: If you close the supercharging control valve at the same time as the connection and perform >#11 operation, excessive force will momentarily act on the transmission belt, belt mechanism, and supercharger, resulting in belt breakage, wear, and supercharging. A huge instantaneous load acts on the machine's bearings, rotors, and vanes, significantly reducing their durability.

The present invention was devised in view of the problem of tilting in the prior art, and provides a mechanical supercharging device that does not suddenly apply a load to the transmission belt mechanism or the supercharger when starting supercharging operation. It is intended for the purpose of

For this reason, the mechanical supercharging device of the present invention has (a) an intake pipe operatively connected to the engine combustion chamber to supply air to the engine combustion chamber, and (b) an air intake pipe that is connected to the combustion chamber in order to supply air to the engine combustion chamber, and (b) a An intake throttle valve is installed in the intake air 1' to control blood flow of the intake air flowing through the intake pipe, and an intake throttle valve is installed in the middle of the intake pipe upstream of the intake throttle valve υ to fully pressurize the intake air and supercharge the engine. The installed supercharger, (2) a belt drive grease attached to the engine crankshaft, (e) a driven grease installed opposite to the blower and rotated for one rotation t = J; ) A transmission belt which is wound around the drive pulley and the drive pulley and transmits the rotation of the drive pulley to the driven pulley;
An electromagnetic clutch is installed between the driven grid and the supercharger and connects and disconnects power transmission between the two, and an electromagnetic clutch is connected in the middle of the intake pipe to bypass the supercharger. It branches from the intake pipe near the charger suction side, and there is an angular connection in the intake pipe near the supercharger discharge side. Shitapai and Yasu pipes and (
'J) A supercharging control valve installed in the pipe/gas pipe, which allows intake air to bypass the supercharger if the supercharger is not operating when the valve is closed. It allows natural intake of air into the engine combustion chamber via the bypass pipe, and when the supercharger is operating, the air pressurized by the supercharger is passed from the turbocharger discharge side to the bypass pipe. The air is returned to the suction side of the turbocharger via the air pipe, completely nullifying the boost pressure, but when the valve is closed, the bypass pipe is completely disconnected and the pressurized air is returned to the turbocharger. and (2) is connected to the intake throttle valve and generates an electric signal when the intake throttle valve opens 1-ir4 beyond the first set opening. (c) a relay means connected to the throttle opening detector and configured to energize an electromagnetic clutch in response to the electric signal to start rotation of the supercharger; Q) Depending on the opening movement of the intake throttle valve, the supercharging control valve 'f! : An interlocking means for interlocking the intake throttle valve and the supercharging control valve in order to close the valve and, conversely, fully open the supercharging control valve in response to the closing movement of the intake throttle valve. The interlocking means closes the supercharging control valve only when the intake throttle υ valve rotates beyond a second set opening, which is larger than the first set opening. When the valve opening is below the first setting, the IL magnetic clutch is deactivated to stop the supercharger, and the supercharging control valve is opened to allow full natural intake of the engine via the bypass pipe, and the intake throttling system is activated. When the valve rotates beyond the first set opening degree, the supercharging control valve is opened, and while the piston pipe is kept conductive, the electromagnetic clutch is first activated to start the turbocharger to rotate. The supercharger is rotated with no load, and then when the intake throttle valve rotates beyond the second set opening, the intake throttle is activated! The supercharging control valve is gradually closed in response to the valve opening movement of 1 liter, and the bypass line is shut off, so that the full load is gradually applied to the supercharger. .

Next, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows an embodiment in which the present invention is fully applied to an internal combustion engine equipped with an electronically controlled injection system, in which air for combustion is supplied to an air cleaner 10. Air flow meter 12. Intake pipe 14. +l
-・Zotank 16. It is supplied to the combustion chamber 20 of the engine via the intake pipe 18. A fuel injection valve 22 is installed in the intake pipe 18, and an air flow meter 12
Intake air flow rate, engine speed, and other i detected by
The electronic control unit 24 calculates the injection ratio based on the j parameter, and outputs a corresponding output signal from the electronic side tilt 1 unit to the injection valve 22 so that a desired amount of fuel 1 can be injected into the intake air. It has become.

As is well known, the intake valve 14 is provided with an intake throttle valve 26 which is linked to the accelerator pedal of the vehicle. Is there a vane in the intake pipe 14 upstream of the intake throttle valve 26? 7'28 is installed. In the illustrated example, the working chamber 30 of the pump has an intake v
14, but it goes without saying that the intake pipe and the working chamber may be constructed separately. You can also use C
A driven pulley 34 is rotatably supported coaxially with the rotor 32 of the vane pump f2B.
4 is a drive groove 38 that can be accessed at one end of the crankshaft 36.
It is designed to be driven via a belt 40. A known electromagnetic clutch (not shown) is provided between the driven pulley 34 and the rotor 32.
7 so that it can be mechanically connected to and disconnected from the rotor 32. A conventional throttle opening detector 42 is connected to the intake throttle valve 26.
When the opening degree is rotated beyond a first set opening degree of 9, an electrical signal can be output to the relay 44. When the relay 44 receives an electric signal from the throttle opening detector 42, it can supply current from a t source (not shown) to the electromagnetic clutch.

Suction 911+ 46 and discharge side 48 of Vanebon 7″28
A pipe line 50 that bypasses the pump is connected between the pump and the pump. A butterfly valve-shaped supercharging control valve 52 is installed in this bypass line 50. The intake throttle valve 26 and the supercharging control valve 52 are connected by a mechanical link 5a, so that when the intake throttle valve 26 opens, the supercharging control valve 52 closes, and conversely, when the former 26 closes, the latter closes. 52 can be opened.

Therefore, this link 54 allows the supercharging control valve 52 to be fully closed only when the intake throttle valve 26 is rotated beyond the second set opening degree, which is wider than the first & constant opening degree. It is set as follows. This can be easily accomplished by adjusting the play in link 54. Instead of the mechanical link 54, it is also possible to interlock the intake throttle valve 26 and the supercharging control valve 52 using a hydraulic interlocking means, a pneumatic movement means, or the like.

Next, the operation of the supercharging device according to this embodiment will be explained.

The engine is continuously running at idle or at light load.
The intake throttle valve 26 is at an opening smaller than the first set opening, the relay 44 is not energized, and the electromagnetic clutch is disconnected. Therefore, vane pump 28 is stopped. At this time, since the supercharging control valve 52 is in the open position, intake air is being drawn into the engine via the intake pipe 50.

Next, the engine load increases and the intake throttle valve 26 moves to the first position.
When the set opening is reached, the throttle opening detector 42 outputs an electric signal to energize the relay 44, so that the electromagnetic clutch is activated and the vane pump is started to rotate. but,
In this state, the supercharging control valve 52 is still open, so the excess air forced by the vane pump 28 is returned to the suction side from the pump discharge side 48 through the bypass line 50, and the pump is effectively There is no load on it. Therefore, the moment the electromagnetic clutch is connected, the belt 40
The forces acting on each part of the vane pump 28 are only acceleration resistance and frictional resistance of the vane pump, and no excessive force is applied.

Next, when the intake throttle valve 26 rotates from time to time and exceeds the second set opening degree, the supercharging control valve gradually closes in response to the rotation of the intake throttle valve 26 until it is finally fully closed.

For this reason, the pinosu pipeline 50 is cut off, and the vane 4
The engine 7'28 is now operated at full capacity. However, the supercharging control valve 52 is linked to the intake throttle valve 26,
Since the supercharging control valve 52 gradually closes as the intake throttle valve 26 rotates beyond the second set opening degree, the bypass pipe 50
As a result, it is gradually blocked within a minute time.
The load on the vane pump 28 will also gradually increase within this minute time. Therefore, no sudden force is applied to the belt or pump parts.

Figure 2 is a graph schematically illustrating these conditions, and P
! and P2 represent the first and second set opening degrees of the intake throttle valve, respectively. In the graph of Figure 2, in region A, the electromagnetic clutch and ch are OFF, and the blower is stopped. In region B, the electromagnetic clutch is ON, but the supercharger rotates with no load. C represents the partial local supply region, and when the intake throttle valve exceeds the second set opening Pzk, the supercharging control valve is gradually closed according to the opening. is full load operation.〇As is clear from the above, in the supercharging system of the present invention, the turbocharger is operated at full load after passing through two stages of continuous no-load operation and partial load operation. And the load acting on the superchargers is also distributed, and their durability can be greatly improved overall.

Further, this also has the advantage that the transmission belt mechanism can be made smaller and lighter.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view of an engine equipped with a mechanical overloading valve according to an embodiment of the present invention, and FIG. 2 is a graph showing the interlocking relationship between the intake throttle p-valve and the supercharging control valve. 14.18... Intake pipe, 20... Engine combustion chamber, 26
...Intake throttle valve, 28...Vane pump, 34...
・+Ai dynamic pulley, 36... crankshaft, 38...
Drive pulley IJ-140... Belt, 42... Throttle opening detector, 44... Relay, 46... Pump suction side, 48... Pump discharge side, 50... Binary 1
Road, 52... Supercharging control valve, 54... Link. Intake throttle valve opening

Claims (1)

[Scope of Claims] (a) An intake pipe operatively connected to the combustion chamber to supply air to the combustion chamber of the engine; (c) An intake throttle valve installed in the intake pipe to control the flow rate; (c) an intake throttle valve installed in the intake pipe to pressurize the intake air and supercharge the engine
a supercharger installed in the middle of the intake pipe upstream of the valve; (b) a belt-driven pulley attached to the engine crankshaft; and (e) a driven pulley rotatably provided opposite the blower. (f) a transmission belt that is wrapped around the driving pulley and the driven pulley and transmits the rotation of the driving pulley to the driven pulley; and (g) disposed between the driven pulley and the supercharger. (a) An electromagnetic clutch that connects the turbocharger in the middle of the intake pipe and connects it to the intake pipe near the intake side of the turbocharger. A bypass pipe that branches off and rejoins the intake pipe near the turbocharger discharge side, and a supercharging control valve installed in the 81 bypass pipe that controls the turbocharger when the valve is closed. When the turbocharger is not operating, it allows intake air to bypass the supercharger and be naturally drawn into the engine combustion chamber via the pi-bus line, and when the supercharger is operating. The air pressurized by the turbocharger is recirculated from the turbocharger discharge side to the turbocharger suction side via the bypass pipe to nullify the boost pressure, but when the valve is closed, the pi (2) A device that blocks the pipe line to prevent the air pressurized by the supercharger from flowing back to supercharge the engine; A throttle opening detector that outputs an electrical signal when the throttle valve opens beyond a first set opening; and a throttle opening detector that is connected to the throttle opening detector and responds to the electrical signal. Q) A relay means that energizes a magnetic latch to start rotation of the turbocharger; interlocking means for interlocking the intake throttle valve and the supercharging control valve to open the jυ supply sub-control valve in accordance with the motion; The supercharging control valve is closed only when the opening of the first setting is greater than the second opening, which is larger than the opening of the second setting.Therefore, when the intake throttle valve is less than the opening of the first setting, the electromagnetic clutch is closed. At the same time, the ifW feed control valve is opened to allow natural intake of the engine via the bypass pipe, and the intake throttle valve is rotated beyond the first set opening. When the engine moves, open the supercharging control valve and enjoy! With the switch and path connected, first, all seven electromagnetic clutches were activated to start the turbocharger and rotate with virtually no load, and then the intake throttle valve was rotated beyond the second set opening. A mechanical overcharging system for an internal combustion engine characterized in that the supercharging control valve is closed gradually in response to the opening movement of the intake throttle valve, completely blocking the bypass pipe, and gradually applying a load to the blower. Feeding device.