JPS5930179Y2 - supercharger - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a supercharger.

In conventional supercharged engines, supercharging is performed over the entire operating range from low rotation and low load operating conditions to high rotation and high load operation.

Therefore, the supercharger must be matched well over this wide range of operating conditions, and this is where the biggest problem lies.

As one way to solve this problem, for example, USP3
As shown in No. 557549, a supercharger is equipped with two scrolls, and when the engine is running at low speeds, all the exhaust gas is concentrated on one scroll and it is rotated at high speed. A method has been developed to prevent boost pressure from increasing too much by supplying exhaust gas to the scroll in a distributed manner.

``This is an extremely clever method, and is a valuable means of greatly expanding the matching range of the engine and supercharger.

Further, in a diesel engine, the amount of air taken into the fuel chamber is approximately constant, and only the amount of fuel injection changes whether the engine is operating under low load or high load.

Therefore, in low/medium load operating conditions, the amount of air is excessive compared to the amount of fuel injection.

Therefore, supercharging under this operating condition will only unnecessarily increase friction and worsen fuel efficiency.1. - It is also conceivable to control the flow of exhaust gas to the supercharger so that supercharging is performed only in high-load operating conditions where air is insufficient, and not in other cases.

In other words, the supercharger function is canceled during low/medium load operation, and is used effectively only during high load operation.

Alternatively, if the boost pressure increases more than necessary,
The exhaust bypass device that allows exhaust gas to flow down without supplying it to the supercharger is also used for the purpose of protecting the engine.
This example can serve as a means to successfully match an engine and a supercharger.

Since all of these control the flow of exhaust gas, the gist of the present invention is to use a single control valve to achieve the respective functions and effects.

An embodiment of the present invention shown in the figure will be explained in detail below. In the figure, 10 is the engine body, 11 is its combustion chamber, 1
2 is an intake valve, 13 is an exhaust valve, 14 is an intake port, and 15 is an intake port.

20 is a supercharger, a turbine 21 and a compressor 22 are directly connected through a shaft 23, and the turbine is provided with two scrolls 24 and 25.

Along with this turbine 21, the turbine inlet is also 2
It is divided into two independent parts, 6 and 27.

In addition, the air flowing in from the compressor inlet 28 is transferred to the intake pipe 2
9 is supplied to the combustion chamber 11 via the intake port 14, and the exhaust gas discharged from there flows into the turbine population 26° 2T via the exhaust duct 30 and reaches the turbine outlet 31. .

40 is a control valve, and its valve body 41 controls the opening and closing of the seat 42 and the gate 43.

That is, the seat 42 is provided on the partition wall 32 that can separate the turbine sections 26 and 27 independently from each other, and the gate 43 is provided on the outer wall 33 of the exhaust duct 30 that partitions the turbine section 27 together with the partition wall. Furthermore, both of them are arranged so that they have the same axis in the advancing and retracting direction of the valve body 41, and when the valve body 41 is seated on the seat 42, the entire amount of exhaust gas is connected to the scroll 24. Although the valve element is lifted from the seat, while the gate 43 is closed, the exhaust gas is dispersed and flows into the two turbine ports 26 and 21, and furthermore, the valve element lifts from the seat. When opened, exhaust gas can flow down from the gate to the turbine outlet 31 via the bypass passage 44 in addition to the above-mentioned flow.

45 is a power motor that operates the valve body 41, and has an atmospheric pressure chamber 4T and a pressure chamber 48 separated by a diaphragm 46 to which the valve body is attached, and a spring 49 is housed in the atmospheric pressure chamber 47. It's important.

The boost pressure in the intake space 29 can be introduced into the pressure chamber 48 through a three-way valve 50 through a boost pipe 51, or the pressure from a pressure source 53 such as an air tank can be introduced through a pressure pipe 52. There is.

Therefore, when the three-way valve 50 establishes communication between the pressure chamber 48 and the pressure source 53, the diaphragm 46 of the power motor 45 immediately pulls up the flexible valve body 41 to open the seat 42 and the gate 43.

Also, while the three-way valve communicates the boost pipe 51 and the pressure chamber, the valve body is on the seat 42 when the boost pressure in the intake pipe 29 is low, but when the boost pressure increases, it automatically It lifts from the seat and works to introduce exhaust gas into the turbine population 27.

If the boost pressure further increases, the valve body can also open the gate 43 and allow the exhaust gas to be discharged to the bypass passage 44 or the turbine outlet 31.

As described above, according to the turbocharger of the present invention, there is surplus air during low and medium load operating conditions, and supercharging is not required, but rather the exhaust pressure becomes excessive compared to the intake pressure, resulting in poor fuel efficiency. In such an operating state, if it is desired to cancel the function of the supercharger 200, the pressure of the pressure source is introduced into the pressure chamber 48 to supply exhaust gas to the turbine 21 (from the bypass passage 44 to the turbine outlet 31). Depending on the strength of the boost pressure, the exhaust gas can be caused to flow down only to the scroll 24 (during low/medium speed rotation) or to both scrolls 24.
25 (during high-speed rotation) and discharging exhaust gas from the bypass passage 44 (exhaust bypass) to prevent an abnormal increase in boost pressure, using only one valve body 41. This makes it possible to provide a compact and inexpensive supercharger compared to a case where separate valve structures are provided for each function.

In addition, since the valve body 41 performs the three functions described above,
This operation becomes frequent and causes inconvenience such as burn-in (
(can do.

Furthermore, by detecting the fuel lever position, the injection pump rack position, the amount of accelerator pedal depression, etc., and operating the three-way valve, it is easy to cancel the supercharger function during low/medium load operation. Although it is possible, it is not necessary to add this canceling effect to the present invention.

[Brief explanation of drawings]

The figure is a schematic vertical sectional view showing an embodiment of the present invention. 10; Engine, 20; Supercharger, 21; Turbine, 22
;Compressor, 24, 25;Scroll, 26, 2
7; Turbine inlet, 29; Intake pipe, 30; Exhaust duct, 31; Turbine outlet, 32; Partition wall, 33; Outer wall, 4o
; Control valve, 41; Valve body, 42; Seat, 43; Gate,
44; bypass path, 45; power motor, 5o; 3-way valve.

Claims (1)

[Scope of utility model registration request] In a supercharger equipped with a turbine and a compressor, the turbine is equipped with two scrolls, and the turbine inlet connected to the exhaust duct is also divided into two independent parts, and a partition wall extending from the turbine inlet is installed. A gate is disposed on the outer wall cooperating with the partition wall to define one turbine inlet, and the gate is connected to the turbine outlet via a bypass passage, and the only valve body is disposed between the seat and the partition wall. A supercharger comprising a control valve capable of closing a gate, opening a seat and closing the gate, and opening the seat and gate.