JPH09217671A - Valve shaft for rotary solenoid actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lighten a valve shaft an reduce the weight of manufacturing process by forming the valve shaft of an integral molding by aluminum casting. SOLUTION: A valve shaft 9 for a rotary solenoid type actuator furnished with a shaft part 10 to be supported on a housing free to rotate and a valve part 16 to increase and decrease a passage area of a fluid passage of the housing is formed of an integral molding by aluminum casting. It is possible to provide the valve shaft 9 which is lighter in comparison with a conventional one made of two stainless steel parts and to reduce the number of manufacturing processes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve shaft for a rotary solenoid type actuator used as an idle speed control device in an automobile engine, for example.

[0002]

2. Description of the Related Art An example of a rotary solenoid type actuator used as an idle speed control device in an automobile engine will be described with reference to an explanatory view of FIG. Note that FIG. 3A is a front sectional view, and FIG. 3B is a sectional view taken along line BB of FIG. In FIG. 3, the fluid passage 2 formed in the housing 1 includes an inflow port 3 and a first outflow port 4 which are opened on the lower surface of the housing 1, and a second outflow port 5 which is opened on the upper surface and provided with a communication pipe 6. Have Although not shown, the housing 1 is mounted on the side wall of the throttle body of the engine as is well known, and the fluid passage 2 forms a bypass passage that bypasses the intake passage of the throttle body through the inlet 3 and the first outlet 4. The communication pipe 6 of the second outlet 5 is connected to the negative pressure inlet of the vacuum switching valve.

As shown in FIG. 3A, a valve shaft 9 is rotatably supported in the housing 1 via left and right bearings 7 and 8. The valve shaft 9 has a shaft portion 10 having bearing surfaces 11 and 12 into which the left and right bearings 7 and 8 are fitted, and a valve sliding surface 17 that opens and closes the fluid passage 2 of the housing 1 to increase or decrease the passage area. Part 16
And are integrally provided. Further, the shaft portion 10 has an engaging convex portion 13 having a width across flats that projects to the right end thereof, and a small-diameter shaft portion 14 that projects to the left end thereof.

A bimetal holder 20 that engages with the engaging protrusion 13 of the shaft portion 10 is rotatably fitted in the housing 1. A bimetal support plate 21 that covers the open end surface of the housing 1 is attached to the housing 1. A coil-shaped bimetal 2 is provided between the bimetal support plate 21 and the bimetal holder 20.
2 are interposed. Further, the housing 1 is provided with a hot water passage (not shown) adjacent to the bimetal 22 and having a hot water connection pipe 23. The hot water connection pipe 23 is connected to the water jacket of the engine, and there are two for the forward path and one for the return path, and one of them is shown in FIG. 3 (a). The bimetal 22 is
It is sensitive to the temperature of engine cooling water circulating in the hot water passage, and the rotational position of the valve shaft 9 is adjusted according to the temperature.

A solenoid housing 26 of a rotary solenoid 25 is attached to the left end surface of the housing 1. A stator 27 and a solenoid coil 28 are housed in the solenoid housing 26 in a state of being molded with resin. Further, the shaft portion 10
A magnet 29 is attached to the small-diameter shaft portion 14.

In the rotary solenoid type actuator, the valve shaft 9 is rotated in the forward and reverse directions by controlling the duty of the energization of the solenoid coil 28 of the rotary solenoid 25 by the engine control computer. As a result, the passage area of the fluid passage 2 is increased or decreased, whereby the flow rate of the air flowing through the fluid passage 2 as a bypass passage is controlled. The rotary solenoid type actuator as described above is disclosed in, for example, Japanese Utility Model Laid-Open No. 4-91268.

Next, a conventional product of the valve shaft 9 used in the rotary solenoid type actuator will be described with reference to the explanatory views of FIGS. In addition, each figure (a) is a front view and (b) is a right side view. FIG. 4
(C) is CC sectional view taken on the line (a). The conventional valve shaft 9 shown in FIG. 4 includes a shaft member 10 (which has the same reference numeral as the shaft portion) that constitutes a shaft portion 10.
And a valve member 16 (which has the same reference numeral as the valve part) that constitutes the valve part 16. Since the magnet 29 is attached to the small-diameter shaft portion 14 of the shaft member 10 as described above, the magnetic material needs to be a non-magnetic material in order to leak magnetism, and is made of an austenitic stainless steel material (for example, SUS303). The valve member 16 is made of the same stainless material as the shaft member 10.

The manufacturing process of the valve shaft 9 will be described. The shaft member 10 is formed by cutting a shaft material made of stainless steel. A single piece of this shaft member 10 is shown in FIG. The valve member 16 is formed by press-forming a stainless steel plate material. A single piece of this valve member 16 is shown in FIG. As shown in FIG. 6, the valve member 16 has a U-shape having mounting pieces 16b at both ends of the main plate portion 16a, and has mounting holes 18 in the mounting pieces 16b.

Next, the shaft member 10 and the valve member 16 are integrated to form a valve shaft 9. That is, as shown in FIG. 7, the shaft member 10 is fitted into the mounting hole 18 of the mounting piece 16b of the valve member 16, and the fitting portion of the mounting hole 18 is welded. At the time of this welding, as shown in FIG. 7 (b), with reference to the two-face width surface 13 a of the engaging projection 13 of the shaft member 10, the two-face width surface 13 a and the valve member 1 are used.
Positioning is performed so that the angle θ formed by the center line L of the main plate portion 16a of No. 6 is 90 °. Next, the valve shaft 9 obtained in the previous step is subjected to polishing to finish the bearing surfaces 11 and 12 of the shaft portion 10 and the valve sliding surface 17 of the valve portion 16 as shown in FIG. The reason why the polishing process is required is that the shaft member 10 and the valve member 16 are made of stainless steel, and therefore the surface roughness and the dimensional accuracy that meet the requirements cannot be obtained in the cutting process.

[0010]

Since the conventional valve shaft 9 is made of stainless steel, it is heavy and causes a decrease in responsiveness of the rotary solenoid actuator. In terms of manufacturing, the shaft member 10
A number of processes such as a cutting process, a pressing process for the valve member 16, a welding process for the shaft member 10 and the valve member 16 and a positioning process therefor, and a polishing process for the bearing surfaces 11 and 12 and the valve sliding surface 17 are required. ing.

The present invention has been made in order to solve the above-mentioned problems, and the problem to be solved by the present invention is to reduce the weight and manufacture by forming an integrally molded product by aluminum casting. It is intended to provide a valve shaft for a rotary solenoid type actuator that can reduce the number of steps.

[0012]

In order to solve the above-mentioned problems, the invention of claim 1 is provided with a rotary solenoid provided with a shaft portion rotatably supported in the housing and a valve portion for increasing or decreasing the passage area of the fluid passage of the housing. Is a valve shaft for a rotary solenoid actuator that rotates by controlling the energization of the coil to control the flow rate of the fluid flowing through the fluid passage, the rotary solenoid actuator being formed as an integrally molded product by aluminum casting. Valve shaft for. This claim 1
According to the rotary solenoid type valve shaft for the actuator described above, since it is formed as an integrally molded product by aluminum casting, it is possible to obtain a lighter product and to reduce the number of manufacturing steps compared with the conventional two-part product made of stainless steel. I'm done. Therefore, according to the rotary solenoid type actuator using this valve shaft, high responsiveness can be obtained at low cost. The invention according to claim 2 is the valve shaft for a rotary solenoid type actuator according to claim 1, which is a die-cast product. According to the valve shaft for a rotary solenoid actuator of the second aspect, since the casting is performed by die casting, a valve shaft having higher productivity and lower cost than other castings can be obtained. According to a third aspect of the present invention, in the rotary solenoid actuator valve shaft according to the first aspect, the length of the connecting portion of the valve portion with respect to the shaft portion in the circumferential direction is substantially half the circumference of the shaft portion. It is a valve shaft for an actuator. According to the valve shaft for a rotary solenoid type actuator of claim 3, unnecessary portions of the valve portion are eliminated as compared with the conventional example in which the length of the connecting portion of the valve portion to the shaft portion in the circumferential direction extends over the entire circumference of the shaft portion. This makes it possible to further reduce the weight.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to the drawings. Since the first embodiment is a modification of a part of the conventional example, the modified part will be described in detail, and the parts which are considered to be the same as or equivalent to those of the conventional example will be denoted by the same reference numerals. FIG. 1 shows an explanatory view of a rotary solenoid type actuator valve shaft 9 according to the present embodiment. 1A is a front view, FIG. 1B is a right side view, and FIG. 1C is a sectional view taken along the line CC of FIG. In FIG. 1, the valve shaft 9 is formed as an integrally molded product by aluminum casting, in this embodiment, aluminum die casting. The bearing surfaces 11 and 12 of the valve shaft 9, the valve sliding surface 17, and the small diameter shaft portion 1
The chamfered surface 14a at the tip of No. 4 is finished by cutting. An explanatory view of the valve shaft 9 before this cutting is shown in FIG. 2A is a front view,
The same (b) is a right side view. Further, as shown in FIG. 1 (c), the length of the connecting portion in the circumferential direction of the mounting piece 16 b of the valve portion 16 with respect to the shaft portion 10 is approximately half the length of the shaft portion 10.

According to the valve shaft 9 for the rotary solenoid type actuator described above, since the valve shaft 9 is formed as an integrally molded product by aluminum casting, a lightweight product can be obtained as compared with the conventional two-piece product made of stainless steel and the manufacturing process. The number is small. Therefore, according to the rotary solenoid type actuator using the valve shaft 9, it is possible to obtain high responsiveness at low cost. Further, since the valve shaft 9 is an aluminum casting, a portion where accuracy and surface roughness are required, that is, the bearing surface 1
By cutting 1 and 12 and the valve sliding surface 17, necessary surface roughness and dimensional accuracy can be obtained, so that the polishing process required in the conventional example can be reduced.

Further, according to the present valve shaft 9, since it is a die cast product, the valve shaft 9 having higher productivity and lower cost than other castings can be obtained. Further, according to the present valve shaft 9, in comparison with the conventional example in which the length in the circumferential direction of the connection between the shaft portion 10 and the valve portion 16 is the entire circumference of the shaft portion 10, the valve portion 1
Unnecessary portions of 6 can be deleted, which enables further weight reduction. Specifically, in the conventional product, as shown in FIG. 4C, the mounting hole 18 is formed in the mounting piece 16b of the valve member 16.
However, according to the present embodiment, as shown in FIG. 1C, the length of the connecting portion in the circumferential direction of the valve portion 16 attachment piece 16b with respect to the shaft portion 10 is the shaft portion 10. Since only about half the circumference is required, the annular portion (marked with diagonal lines in FIG. 1 (c)) in the conventional product can be eliminated, and the weight corresponding to that can be reduced.

The present invention is not limited to the above embodiment, but can be modified without departing from the spirit of the present invention. For example, die casting is suitable for aluminum casting, but it is also conceivable to adopt other high pressure casting, low pressure casting, or the like.

[0017]

According to the valve shaft for a rotary solenoid type actuator of the present invention, the weight can be reduced and the number of manufacturing steps can be reduced. Therefore, by using this valve shaft, it is possible to obtain a rotary solenoid actuator of low cost and high responsiveness.

[Brief description of drawings]

FIG. 1 is an explanatory view of a valve shaft showing an embodiment.

FIG. 2 is an explanatory view of a valve shaft formed by aluminum die casting.

FIG. 3 is an explanatory diagram of a rotary solenoid type actuator.

FIG. 4 is an explanatory diagram of a valve shaft showing a conventional example.

FIG. 5 is an explanatory diagram of a shaft member.

FIG. 6 is an explanatory diagram of a valve member.

FIG. 7 is an explanatory diagram of a semi-finished product of a valve shaft.

[Explanation of symbols]

 1 Housing 2 Fluid Passage 9 Valve Shaft 10 Shaft 16 Valve 25 Rotary Solenoid

Claims (3)

[Claims] 1. A fluid flowing through the fluid passage, which comprises a shaft portion rotatably supported by a housing and a valve portion for increasing or decreasing a passage area of the fluid passage of the housing, and which is rotated by controlling energization of a coil of a rotary solenoid. A valve shaft for a rotary solenoid actuator that controls the flow rate of a rotary solenoid actuator, characterized by being formed as an integrally molded product by aluminum casting. 2. The valve shaft for a rotary solenoid type actuator according to claim 1, wherein the valve shaft for a rotary solenoid type actuator is a die cast product. 3. The valve shaft for a rotary solenoid actuator according to claim 1, wherein the length of the connecting portion of the valve portion to the shaft portion in the circumferential direction is substantially half the circumference of the shaft portion. shaft.