JPS61237832A - Variable capacity supercharger - Google Patents

Abstract

PURPOSE:To improve durability of a clutch mechanism by activating a means for maintaining existing nozzle vane opening condition when a clutch pedal travel is sensed to reduce unnecessary activation of the nozzle vane opening and closing mechanism due to engagement and disengagement of the clutch. CONSTITUTION:To rotate a movable nozzle vane 1 of a variable capacity supercharger, two control cylinders 20 and 20' respectively having different lengths of stroke are equipped. Each of the control cylinders 20 and 20' is made to push each of the piston rods 24 and 24' by introducing high pressure air from an air tank 23 into each of the cylinders 20 and 20' when both white marks on both solenoid valves 22 and 22' are communicated due to command from a controller 21. Here, a clutch switch 29 is turned on when the clutch pedal is depressed, with the existing condition maintaining means 28 being energized at input terminal N with a battery 8 voltage. This makes the existing condition maintaining means 28 maintain and transmit the signal from an immediately preceding controller 21 to each of the solenoid valves 22 and 22'.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention is an improvement of a variable displacement supercharger that improves the characteristics of the supercharger by rotating a movable nozzle vane provided in a turbine housing. Regarding.

[Conventional technology]

Generally, exhaust gas is used to rotate an exhaust turbine,
A supercharging device uses this power to drive a compressor to increase intake pressure (boost pressure) and increase engine output, but when the engine is running at low speeds, the turbine speed is low and effective boost pressure cannot be obtained. Additionally, superchargers that are provided with an exhaust bypass passage (wastegate) to prevent overspeeding of the turbine when the engine rotates at high speeds have poor fuel efficiency at high speeds.

Therefore, as shown in FIG. 4, a movable nozzle vane 1 is provided in the turbine housing 2 of the supercharger, and when the engine 5 is running at low speeds, the nozzle vane 1 is rotated in the closing direction to reduce the capacity of the turbine 4. rotates well to improve low-speed torque, and when the engine 5 rotates at high speeds, the nozzle vane is rotated in the fully open direction to increase the capacity of the turbine, and the rotation of the turbine wheel 3 is reduced to improve fuel efficiency at high speeds. There is a variable capacity supercharger with

As shown in FIGS. 5(A) and 5(B), this variable displacement supercharger drives a nozzle vane 1 provided in a nozzle portion 2a of a turbine housing 2 by a drive device 10 installed outside the turbine housing 2. By rotating it, the flow velocity of exhaust gas flowing out from the nozzle portion 2a to the turbine wheel 3 can be changed. Inside the casing 10a of the drive device IO, there is a rotating shaft 11 that passes through the turbine housing 2 and connects to the nozzle vane 1, a control lever 12 fixed to the other end of the rotating shaft 11, and a control lever 12 fixed to the free end 12a. A control ring 13 that engages with a recess 13a provided on the inner circumference, and a control ring 1
An operating lever 14 for rotating the lever 3 is provided. The actuating lever 14 is connected to an actuating link 16 outside the casing 10a by an actuating shaft 15 passing through the casing 10a, and when the actuating link 16 is rotated by an actuator (not shown), the nozzle vane is moved inside the turbine housing 2. 1 rotates.

Ideally, in the movable nozzle vane drive device configured as described above, the operating lever should be rotated continuously according to the operating conditions of the engine, but if the nozzle vane drive device is configured in this way, it will be costly. The disadvantage is that it is expensive and impractical.

Therefore, in the conventional variable capacity supercharger,
As seen in Japanese Patent No. 9928, it is common to switch the opening degree of the nozzle vane 1 in two to four stages depending on the engine load and rotation speed.

However, in the case of such a variable capacity supercharger for automobiles, each time the clutch pedal is depressed (the clutch is disengaged) to perform a gear change, etc., there is a significant change in engine speed and engine load. Accordingly, the nozzle vane opening degree within the turbine is also controlled and varied each time. This causes each part of the nozzle vane opening/closing mechanism to be operated unnecessarily and frequently, resulting in discomfort due to noise during operation and shortening of lifespan due to wear of the opening/closing mechanism.

[Purpose of the invention]

The purpose of this invention is to eliminate the drawbacks of the conventional variable displacement supercharger, reduce unnecessary operation of the nozzle vane opening/closing mechanism due to turning off and on of the clutch, and reduce wear of each contact part of the nozzle vane opening/closing mechanism. An object of the present invention is to provide an excellent variable capacity supercharger that can improve durability (life) and reduce discomfort caused by noise generated during operation.

[Structure of the invention]

The variable capacity supercharger of the present invention that achieves the above object includes a nozzle vane opening/closing mechanism and its drive control means for varying the area of the exhaust gas inlet of the turbine, means for detecting depression of a clutch pedal, and maintaining the current nozzle vane opening degree. and the drive control means is configured to operate the means for maintaining the current state of the nozzle vane opening when receiving a clutch pedal depression signal from the clutch pedal depression detection means.

〔Example〕

The present invention will be described in detail below using the accompanying drawings.

FIG. 1 shows the configuration of an embodiment of a variable capacity supercharger of the present invention.

In this invention, the control cylinder 20.20' having two different strokes is used as an actuator to rotate the movable nozzle bay 71 of the variable displacement supercharger, for example, the protruding and retracting surfaces 20a+20a' of the piston rod 24.24'.
In the embodiment shown in FIG. 1, the control cylinders 20 and 20' are air cylinders operated by high pressure air. This control cylinder 20.
20' is a solenoid valve 22.
When the white to white lines of 22' are connected, high pressure air from the air tank 23 is introduced into the cylinder 20.20', and the piston rod 24.24', which is the operating rod, is moved to the cylinder 20.20.
' It operates to push out from inside, but the solenoid valve 22.22
When the lines 24 and 24' are in communication, a built-in spring (not shown) moves the piston rod 24, 24' to the cylinder 20.
It is configured to return to its original position within 20'.

A link rod 25 is pivotally attached to the tips of both the piston rods 24 and 24', and its pivot point A,
Axis attachment point A between B and a predetermined position C equidistant from B
An output rod 26 is pivotally attached to (output point C). In this invention, the other end of the output rod 26, which is pivotally attached to the link rod 25 as described above, is rotatably attached to the operating link 16, which is fixed to the operating lever 14 that rotates the control ring 13.

Therefore, in this invention, when the output rod 26 reciprocates in the D-D' force direction, the operating lever 14 rotates in the E-E' direction, and the movement of the operating lever 14 is transmitted from the control ring 13 to the control lever 12. This causes the nozzle vane 1 to rotate.

By the way, in this embodiment, as mentioned above, the output rod 2
The output point C of the link rod 25 to which the piston rod 24. Since the output lot 2 is different,
6 moves to the next four stages depending on whether the control cylinders 20, 20' are activated or deactivated.

That is, (1) when the control cylinders 20 and 20' do not operate together, the nozzle vane 1 is moved to keep it close to the fully open state; (2) when only the control cylinder 20' with the shorter stroke is operated, the nozzle vane 1 is moved so as to be slightly closed; (2) When only the control cylinder 20 with the longer stroke operates, the nozzle vane 1 is moved to open slightly; (2) When the control cylinders 20 and 20' are operated together, the nozzle vane 1 is moved to keep it close to a fully closed state.

The electromagnetic valves 22 and 22' are configured such that, for example, when an on signal is output from the controller 21, the white to white lines are in communication, and when an off signal is output, the black to black lines are in communication. do.

Furthermore, in this embodiment, means 28 for maintaining the current state of signals from the controller 21 are provided in the signal lines 27 and 27' connecting the controller 21 and the solenoid valves 22 and 22', respectively. The means for maintaining the current status of this signal consists of an electronic circuit, etc., and when voltage is applied to the input terminal N, the signal from the controller 21 just before that to the solenoid valves 22 and 22' is maintained as it is. This allows continuous output to the solenoid valves 22 and 22'.

In the present invention, the input terminal N of the current status maintaining means 28 is connected to the battery 8 via a clutch switch 29 that is turned on when the clutch pedal is depressed.

Although not shown in the drawings, the controller 21 receives an engine water temperature signal, a load signal, a rotational speed signal, an air tank internal pressure signal, a supercharging pressure signal, and the like. If the engine is not normal, such as when the water temperature is below a predetermined value, the air tank internal pressure is insufficient, or the rotation speed or load cannot be read, the controller 21 notifies the driver with a warning light, etc. However, when the engine is operating normally, the controller 21 outputs an off signal to the solenoid valves for each zone indicated by ■ to ■, according to the control map shown in Fig. 2. 22 and 22', signals as shown in the table of FIG. 3 are output.

In the variable displacement supercharger of the present invention configured as described above, when the driver depresses the clutch pedal to change gears during normal engine operation, the clutch switch 29 is turned on and the current state is maintained. The voltage of the battery 8 is applied to the input terminal N of the means 28 . Then, the current status maintaining means 28 maintains the signals from the immediately preceding controller 21 as they are and transmits them to the electromagnetic valves 22 and 22', respectively.

Due to this action of the status quo maintaining means 28, the variable capacity supercharger of the present invention is operated as it is in the state immediately before the clutch pedal is depressed, so that the nozzle vane opening/closing mechanism also remains stationary. Then, when the driver finishes changing gears and connects the clutch pedal, the clutch switch 29 is turned off, and signals from the controller 21 corresponding to the new operating state of the engine are sent to the solenoid valves 22 and 22'. is input.

In this case, if the new operating state of the engine is close to the state before the clutch pedal was depressed and within the same zone in the control map shown in Figure 2, the nozzle vane opening will not change at all and the slave lever will During the process, the nozzle vane opening/closing mechanism does not move.

Furthermore, unless the new operating state of the engine changes significantly, the nozzle vane opening/closing mechanism does not move significantly, and the number of times it operates is greatly reduced compared to the conventional method.

In other words, conventionally, each time the clutch pedal was depressed and the engine speed decreased, the nozzle vane opening degree changed significantly.
The variable displacement supercharger of the present invention prevents unnecessary operation of the nozzle vane opening/closing mechanism, in which the nozzle vane opening degree changes greatly each time the clutch pedal is engaged and the engine speed rises again.

Note that the current status maintaining means 28 can also be incorporated into the control procedure of the controller 21.

〔Effect of the invention〕

As explained above, the variable capacity supercharger of the present invention includes a nozzle vane opening/closing mechanism and its drive control means for varying the area of the exhaust gas inlet of the turbine, means for detecting depression of the clutch pedal, and maintaining the current nozzle vane opening degree. and the control device operates the nozzle vane opening degree maintaining means when receiving the clutch pedal depression signal from the detection means, thereby controlling the nozzle vane opening/closing mechanism by turning on and off the clutch. Unnecessary operations are reduced, durability (life) is improved by reducing wear on each contact part of the nozzle vane opening/closing mechanism, and discomfort caused by the noise generated when the nozzle vane opening/closing mechanism is operated is reduced. This has the effect of improving the marketability of the machine.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram showing the configuration of an embodiment of the variable capacity supercharger of the present invention, Fig. 2 is a diagram showing the control characteristics of the controller shown in Fig. 1, and Fig. 3 is a diagram showing the control characteristics of the controller shown in Fig. 2. A table showing the output signal from the controller to each solenoid valve in each zone in the figure,
Fig. 4 is a schematic diagram of a conventional variable displacement supercharger having a movable nozzle vane in the turbine housing, and Fig. 5(A) is a configuration of the movable nozzle vane drive device of the variable displacement supercharger shown in Fig. 4. FIG. 5(B) is a cross-sectional view taken along the line X--X of FIG. 5(A). 1... Nozzle vane, 2... Turbine housing,
3... Turbine wheel, 10... Nozzle vane drive device, 10a... Casing, 11... Rotating shaft,
12... Control lever, 13... Control ring, 4...
- Operating lever, 15... Operating shaft, 16... Operating link, 20.20'... Control cylinder, 21... Controller, 22.22'... Solenoid valve, 23... Air tank, 24.24'...Piston rod, 25.2
5'...Link Rondo, 26...Output lot, 28
...Means for maintaining the status quo, 29...Clutch switch.

Claims (1)

[Claims] The drive control means includes a nozzle vane opening/closing mechanism that changes the area of the exhaust gas inlet of the turbine, a drive control means for the same, a clutch pedal depression detection means, and a means for maintaining the current state of the nozzle vane opening, and the drive control means controls the clutch from the detection means. A variable capacity supercharger that operates the means for maintaining the current state of the nozzle vane opening when receiving a pedal depression signal.