JPS6362982A - Rotary solenoid type actuator - Google Patents

Abstract

PURPOSE:To perform the control of a valve unit on the basis of plural signals, by controlling a magnet to be rotated by coils, formed in the periphery of a core, and by a rotary motion of the core itself. CONSTITUTION:An actuator fixes a magnet 5 onto a driving shaft 8 further provides a core 4 to be arranged so as to coat said magnet 5. And coils 20, 30 are formed being wound on said core 4. While the core 4 is formed able to rotate by a driving means other than the coils, for instance, by a spiral bimetal 12 and a driving boss 13. In this way, the magnet 5 can be controlled to be rotated not only by magnetic force, generated by the coils 20, 30 formed in the periphery of the core 4, but also by a rotary motion of the core 4.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an electric actuator using a coil, which adjusts the amount of bypass air before and after a throttle valve of an engine, for example, and adjusts the idle speed of the engine to a target speed. It is effective when used as an actuator for adjustment.

[Prior art and its problems]

2. Description of the Related Art It has been known to use an electromagnetic actuator as an idle rotation speed control device for an automobile (for example, see Japanese Patent Application Laid-open No. 57-73839).

However, in conventional electromagnetic actuators, improved angle control of the actuator is achieved by complexly controlling signals input to the electromagnetic actuator. Therefore, the conventional device has a problem in that its control circuit is complicated, and in the event that the actuator breaks down, it is difficult to maintain smooth operation of the engine.

[Problem that the invention seeks to solve]

The present invention was devised in view of the above points, and it is intended to simplify the shape of the valve body of a solenoid actuator and to enable the actuator to control the valve body based on a plurality of signals. The purpose is to

[Configuration and action]

In order to achieve the above object, in the present invention, a magnet is fixed on the drive shaft, and a core is further disposed to cover the magnet. A coil is then wound around this core. Furthermore, the actuator of the present invention employs a configuration in which the core is rotatable by a driving means other than the coil. Therefore, according to the actuator of the present invention, the rotation of the magnet can be controlled by the magnetic force generated by the coil formed around the outer periphery of the core, and the rotation of the magnet can also be controlled by rotating the core itself. Ru.

〔Example〕

Hereinafter, one embodiment of the actuator of the present invention will be described based on the drawings.

Reference numeral 9 in FIG. 1 is a housing made of an aluminum alloy or a resin material such as PBT or nylon.

A bypass passage 18 is formed inside the housing 9. A port 19 of the bypass passage 18 opens upstream of the throttle valve in the intake pipe of the engine, and allows bypass air to flow in from the air filter. Further, the outlet 10 of the bypass passage 18 is connected to the intake pipe downstream of the throttle valve, and supplies bypass air to the engine.

A drive shaft 8 is rotatably disposed inside the housing 9. As shown in FIG. 4, a throttle valve 7 is fixed to this drive shaft 8, and this throttle valve 7 is connected to the bypass passage 18.
The passage opening area of the bypass passage 18 is varied together with the valve seat 23 formed in the middle.

The drive shaft 8 is disposed within the cylindrical core 4, and the cylindrical core 4 and the drive shaft are rotatably supported via a bearing 6. The core has detent grooves cut out as shown in FIG. 2.3. This detent groove is
The shape is such that the magnetic path area of the core is reduced around the magnet 5 (as shown in FIG. 5). Therefore, the sixth
As shown in the figure, magnetic resistance occurs in the detent groove 21 portion, and the magnet 5 comes to rest at a position where its magnetic head is adjacent to the core 4 (neutral point position).

A first coil 20 and a second coil 30 are wound around the outer periphery of the core. Further, a yoke 3 is disposed outside both coils 20°30. Note that both the yoke 3 and the core 4 are made of magnetic material. Further, the yoke 3 and the core 4 are assembled so that the core 4 is rotatable. Yoke 3 is fixed to housing 9. A cooling passage housing 14 is also secured to the yoke. A cooling water passage 19 is formed in the housing 14 . Engine cooling water flows into the cooling water passage 19 through an inlet 15, and is led out to the engine through an outlet 16. Further, a bimetal 12 is disposed in the cooling water passage housing adjacent to the cooling water passage. The bimetal 12 has a spiral shape, and its outer peripheral end is fixed to the cooling water passage housing 4. Further, the inner peripheral end portion of the bimetal 12 is fixed to the drive boss portion 13.

The drive boss portion is fixed to the end of the core 4 described above,
As the drive boss rotates, the core 4 can rotate within the yoke 3 by a predetermined angle.

That is, if the bimetal expands or contracts depending on the environmental temperature, the drive boss rotates within the cooling water passage housing in accordance with the displacement. The cylindrical core rotates within the yoke 3 in synchronization with this rotation. This state is shown in FIG. 6.7.8. That is, as the core 40 rotates, the position where the detent groove 21 is formed is displaced. Since the magnetic resistance of this portion is large, the magnet 5 also rotates as the core 4 rotates. In other words, the neutral point position of the magnet 5 is displaced as the drive boss portion 13 rotates.

In this state, if one coil, for example, the first coil 20, is excited, a magnetic flux as shown by the broken line in FIG. 3 is generated.

Since this magnetic flux has a smaller magnetic path area in the core around the magnet 5 (as shown in FIG. 5), magnetic saturation occurs and a part of the magnetism flows toward the magnet 5 side. As a result, the magnet 5 rotates within the core 4 under the influence of magnetism.

When the other coil, for example the second coil 30, is excited, magnetism flows in the core 4 in the opposite direction to that shown in FIG. Therefore, in this case, the magnet 5 within the core 4 will rotate in the other direction.

In this way, the excitation of the first coil 20 causes the magnet to rotate in one direction, and the excitation of the second coil 30 causes the magnet 5 to rotate in the other direction. Therefore, by controlling the duty ratio between the time to excite the first coil 20 and the time to excite the third coil 30, it is possible to control the rotation of the magnet to an arbitrary position. Here, the duty ratio of the electric signals supplied to the first coil and the second coil 30 is controlled by a computer (not shown). Note that the computer determines the bypass passage 18 based on conditions such as engine speed.
operates to control the amount of air flowing through the air.

When the duty ratio is 50%, the excitation forces of the first coil 20 and the third coil 30 are closed, so the magnet 5 stops at the neutral point position. When the duty ratio on the first coil 20 side increases, the magnet rotates in one direction, and conversely, when the duty ratio on the second coil 30 side increases, the magnet rotates in the other direction. In this way, the magnet is controlled by the signal current to the first coil and the second coil, but at the same time, in the actuator of this example,
Core 3 is displaced by bimetal 12.

That is, when the bimetal 12 is at a predetermined temperature, for example, an environmental temperature of 30° C., the drive boss portion 13 rotates the core 4 so that its detent groove is located in the vertical direction,
This state is maintained (the state shown in FIG. 7). In this state, the rotation angle of the magnet 5, that is, the throttle valve 7, is controlled as indicated by the solid line a in FIG.

When the engine coolant temperature is high, that is, bimetal 1
When the environmental temperature of the core 2 is high (for example, about 90° C.), the drive layer section rotates the core 4 to the state shown in FIG. Therefore, in this state, as shown by broken line C in FIG. 9, the rotation angle of the valve body 7 decreases as a whole, and as a result, the flow rate of bypass air flowing through the bypass passage 18 also decreases.

Conversely, when the engine cooling water temperature is low, bimetal 12
In state B where the environmental temperature is low (for example, about -30° C.), the drive boss portion 13 rotates the core 4 to the state shown in FIG. 6 and maintains that state.

In this state, as shown by the dashed line in FIG. 9, the rotation angle of the throttle valve 7 increases overall. Therefore, as shown in FIG. 9, the flow rate of air flowing into the bypass passage 18 becomes large. This state will be further explained with reference to FIG.

FIG. 10 shows when the duty ratio is 50%, that is, when the magnet 5 is at the neutral point position. Even in this neutral position, the throttle valve 7 rotates in accordance with the rotation angle of the drive boss portion due to the displacement of the bimetal 12. As a result, the bypass air flow rate is variably controlled.

Therefore, according to the actuator of this example, the bypass air flow rate is electrically controlled by an electric signal from a computer (not shown), and at the same time, the air flow rate can be variably controlled even in accordance with the displacement of the bimetal 12. . That is, in the actuator of this example, the rotation angle of the throttle valve 7 is controlled based on the unsystematic signal. This means that the actuator of this example can smoothly drive the throttle valve even if a failure occurs in the coil or the like. That is, one coil, for example, the lth coil 20
If the coil fails for some reason, the drive shaft 8 momentarily tries to rotate due to the magnetic force from the other coil, for example, the second coil, but this rotation is suppressed by the resistance of the bimetal 12. Even in this case, if the amount of current applied to the other coil, that is, the second coil 30, is reduced, the magnet 5 returns to the neutral position, and a predetermined flow rate control is possible in that state.

In the above example, the spiral bimetal element 2 and the drive boss portion 13 are used as drive means, but the core 4 may be rotated by other means, such as electrical means.

In addition, in the above example, the core 4 has a cylindrical shape and the detent groove 21 is formed on the circumferential surface of the core 4.
The core 24 may be formed in the shape shown in the figure. That is, in the illustrated example in FIGS. 11 to 13, detent grooves 31 are formed on the inner circumferential surface of the core. Even if the detent groove is formed on the inner circumferential surface of the core 24, in the sense of forming magnetic resistance on the outer circumference of the magnet 5, the above-mentioned second
The same operation as the detent groove 21 shown in FIG. 3 is performed.

In the examples shown in FIGS. 11 to 13, the core is divided into a movable part 24 and a fixed part 22.

A first coil 20 and a second coil 30 are wound around the outer periphery of the fixed portion 22 of the core.

〔Effect of the invention〕

As explained above, in the actuator of the present invention, the core is movable and the core is formed to be rotated by other driving means, so the rotation can be accurately controlled using the magnets arranged inside the core for multiple signals. be able to.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the actuator of the present invention, FIG. 2 is a front view showing the core shown in FIG. 1, FIG. 3 is a side view of FIG. 2, and FIG. 4 is a side view of the core shown in FIG. A sectional view taken along the line B-B, FIG. 5 is an explanatory diagram showing the relationship between the developed magnetic path angle and the magnetic path path area, and FIGS.
9 is an explanatory diagram showing the relationship between duty ratio and flow rate, Figure 1O is an explanatory diagram showing the relationship between water temperature and flow rate, and Figure 11 is an explanatory diagram showing the relationship between the actuator of the present invention and other Figures t2 and 13 are cross-sectional views showing essential parts of the core example shown in Figure 1. 4... Core, 5... Magnet, 7... Throttle valve, 8...
・Drive shaft. 12...Bimetal.

Claims (3)

[Claims] (1) A housing having a fluid passage; a drive shaft rotatably disposed within the housing; a throttle valve fixed to the drive shaft and configured to vary the passage area of the fluid air passage; It is characterized by comprising a fixed magnet, a core disposed to cover the magnet, a coil wound around the core, and a driving means for rotationally driving the core in the rotational direction of the magnet. Rotary solenoid actuator. (2) The rotary solenoid actuator according to claim 1, wherein the drive means is made of bimetal and rotates the core by a predetermined angle in response to changes in environmental temperature. (3) A patent characterized in that the core has a cylindrical shape, and a detent groove is formed in the core to form magnetic resistance at an outer peripheral portion of the magnet in the cylindrical core. A rotary solenoid actuator according to claim 1.