JPH0229251Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an air regulator (auxiliary air valve) for an internal combustion engine.

<Prior Art> In a conventional electronically controlled fuel injection internal combustion engine, air is taken in from an air cleaner 1 through an air flow meter 2, a throttle chamber 3, and an intake manifold 4, and then While the intake throttle valve 5 provided in the chamber 3 controls the flow rate, a bypass passage 6 is provided that connects the upstream and downstream sides of the intake throttle valve 5, and an air regulator 7 is interposed in the bypass passage 6. By increasing or decreasing the opening degree of the bypass passage 6 with this air regulator 7, the flow rate of the air that is supplied in an increased amount by bypassing the intake throttle valve 5 is controlled to smoothly perform warm-up operation at low temperatures. We are making it possible to do so. 8
is the fuel injection valve.

As the air regulator 7, there is, for example, one described in Japanese Utility Model Application Publication No. 104334/1983. This is constructed as shown in FIGS. 4 to 6, and includes a cover 10 provided with an inlet passage 9 at an eccentric position, an outlet passage 11 provided at an eccentric position, and an eccentric on the opposite side of the outlet passage 11. A shutter chamber 14 is formed between the main body 13 and a bimetal chamber 12 provided therein, and the inlet passage 9 and the outlet passage 11 are opposed to each other through a part of the shutter chamber 14. .

Further, an adjusting plate 15 is attached to the end face of the main body 13 on the shutter chamber 14 side, and a shutter 16 is rotatably attached to the center of the adjusting plate 15 by means of a pin 17.

Incidentally, openings 18 and 19 corresponding to the openings of the outlet passage 11 and the bimetal chamber 12 are formed in the adjusting plate 15, and
Seats 20 and 21 are formed around the peripheries of these openings 18 and 19 to be in sliding contact with the shutter 15.

The bimetal chamber 12 houses a bimetal 23 around which a heater 22 is wound, and this bimetal 23
The distal end thereof is made to protrude inside an opening 19 provided in the adjusting plate 15. By tensioning and holding the return spring 25 between the pin 24 fixed on the adjusting plate 15 and the shutter 16, the protrusion 27 on the edge of the opening 26 provided in the shutter 16 is fixed to the bimetal 2.
3, the position of the shutter 16 is changed in accordance with the thermal deformation of the bimetal 23. 28 is a stopper for regulating the maximum rotational position of the shutter 16; 29 is an opening provided in the shutter 16 corresponding to the opening 18 of the outlet passage 11; and 30 is a cap that covers the opening 26.

In such an air regulator 7, energization to the heater 22 is started from the time the engine starts, but the bimetal 23 is maintained at a low temperature during warm-up operation. For this purpose, the shutter 16 whose rotational position is determined by the bimetal 23 is in the fully open position with the return spring 25 fully extended as shown in FIG. Opening 1 of plate 15
8 are almost in agreement. Therefore, the inlet passage 9 and the outlet passage 11 communicate with each other over a sufficiently large area, and the amount of air that bypasses the intake throttle valve 5 increases, so that the intake air amount of the engine is corrected to increase.

When the warm-up is completed, the temperature of the bimetal 23 also rises, so its tip moves toward the right in the figure, and the urging force of the return spring 25 causes the shutter 16 to rotate counterclockwise in the figure. The result will be as shown in Figure 6. Then, the opening 2 of the shutter 16
9 and the opening 18 of the adjusting plate 15 are misaligned, so the inlet passage 9 and the outlet passage 11 are cut off, and the correction for increasing the amount of intake air is stopped.

<Problems to be solved by the invention> By the way, in such a conventional air regulator 7, since the heater 22 is always energized when the vehicle is running, that is, during normal operation of the engine, the bimetal chamber 12 The ambient temperature may become too high, and in this case, even though the rotation of the shutter 16 is regulated by the stopper 28, the bimetal 23 still moves to the high temperature side (on the right side in the figure) depending on the temperature. As a result, a gap 31 is formed between the bimetal 23 and the protrusion 27, as shown by the dashed line in the figure.

Then, if the bimetal 23 resonates with engine vibration in a specific rotation range of the engine, this vibration causes the bimetal 23 to move toward the protrusion 27.
This causes damage to the bimetal 23 or abrasion of the protrusion 27. In either case, the static flow rate (temperature-flow rate) characteristics of the air regulator change, making it difficult to start the engine. Another problem was that the stability at low temperatures decreased.

The present invention was developed to solve these conventional problems, and suppresses the resonance of the bimetal under any conditions, thereby preventing damage to the bimetal or wear of the shutter. The purpose is to improve the reliability and durability of air regulators.

<Means for solving the problem> To this end, in the present invention, a spring wave washer is interposed between the shutter and the head of the pin that pivotally supports the shutter to provide rotational resistance to the shutter and , a spring is provided integrally with the shutter to clamp the bimetal together with the shutter.

<Function> As a result, the displacement of the bimetal is transmitted to the shutter via the spring, and the vibration (resonance) of the bimetal is suppressed so that the shutter and the bimetal are always integrated, thereby reducing the interaction between the bimetal and the shutter. Collisions are avoided to prevent these types of wear.

<Example> An example of the present invention will be described below in detail based on FIGS. 1 and 2. Note that parts having the same functions as those of the conventional example shown in FIGS. 3 to 6 are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

That is, in the present invention, as shown in FIGS. 1 and 2, the shutter 16 is connected to the adjusting plate 1.
A pulling wave washer 32 is sandwiched and held between the head 17a of the pin 17 pivotally supported by the shutter 16 and the shutter 1 is held by its frictional force.
5 to provide a predetermined rotational resistance to the stopper 2.
Shutter 1 near the tip of bimetal 23 from the 8 side.
By welding and fixing the spring 33 that presses toward the protrusion 27 of 6 to the cap 30, the bimetal 23 is placed between the spring 33 and the protrusion 27.
is held in between.

In the air regulator 7 having such a configuration, when the bimetal 23 is thermally deformed (flexed) in response to the ambient temperature of the bimetal chamber 12, the position of the shutter 16 (the communication between the inlet passage 9 and the outlet passage 11) is changed via the spring 33. The amount of air bypassing the intake throttle valve 5 and being supplied to the engine is corrected.

Driving (position control) of the shutter 15 like this
When the engine vibrates, the bimetal 2
When the shutter 3 vibrates, the shutter 16 also tries to vibrate, but a frictional force is applied to the shutter 15 in the direction of rotation by the pulling wave washer 32. Also, the spring 33 is different from the bimetal 23.
acts as if it were a damper and suppresses the vibration of the bimetal 23, causing vibration (resonance).
This prevents collisions from occurring, and wear of the shutter 16 and bimetal 23 is suppressed.

The warm-up of the engine is then completed (Bimetal 2
3), the bimetal 23 bends significantly, causing the shutter 16 to abut against the stopper 28 as shown in FIG. Therefore, when the temperature of the bimetal 23 becomes higher and its bending becomes larger, the shutter 16 comes into contact with the stopper 28, and the bimetal 23 floats up from the protrusion 27 of the shutter 16, creating a gap 31 ( (see FIG. 6) is formed. However, as described above, the spring 33 comes into contact with the vicinity of the tip of the bimetal 23, essentially supporting the bimetal 23 at two points and preventing its free movement, so that the resonance of the bimetal 23 is suppressed. become.

The spring 33 that presses the bimetal 23 in this way is composed of a wave-shaped leaf spring or the like as shown in the embodiment.
The specific structure is arbitrary as long as it is elastically deformed in response to thermal deformation of the bimetal 23 and can suppress resonance of the bimetal 23 by the elastic force of the spring 33. Furthermore, in order to suppress the resonance of the bimetal 23 more efficiently, it is of course preferable to use a spring with a large internal friction (vibration damping function).

<Effects of the invention> As explained above, according to the invention, the bimetal is held between the spring and the shutter, and
By applying rotational resistance to the shutter with a spring wave washer, the movement of the bimetal and the shutter is unified, so if the bimetal bends greatly as the temperature rises and the shutter and bimetal Even if a gap is formed between the two, it is small and can effectively suppress the vibration of the bimetal, especially the resonance that occurs at a certain rotation speed of the engine. Wear on the shutter side can also be prevented, and the intake air amount increase correction characteristic based on temperature can be stabilized over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a front view of essential parts showing an embodiment of the present invention, FIG. 2 is a cross-sectional view taken from FIG. 1, and FIG. 3 is a schematic cross-sectional view showing a conventional example of an electronically controlled fuel injection internal combustion engine. FIG. 4 is a sectional view showing a conventional example of an air regulator, and FIGS. 5 and 6 are sectional views taken along the - sectional line in FIG. 4 in different operating states. 5...Intake throttle valve, 6...Bypass passage, 7...Air regulator, 9...Inlet passage, 11...Outlet passage, 1
6...Shutter, 17...Pin, 17a...Head, 22
...Heater, 23...Bimetal, 27...Protrusion, 28
...stopper, 32...spring wave washer, 33...spring.

Claims (1)

[Scope of utility model registration request] In an air regulator for an internal combustion engine, the air regulator includes a shutter that variably controls the opening degree of a bypass passage connecting upstream and downstream of an intake throttle valve, and a bimetal that drives the shutter. An air regulator for an internal combustion engine, characterized in that a spring wave washer is interposed between the head and the shutter to provide rotational resistance to the shutter, and a spring is provided integrally with the shutter to clamp the bimetal together with the shutter.