JPH1193906A - Actuator made of resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light actuator made of resin to prevent the occurrence of breakage of a weld part due to a heat shock (a heat cycle), heat aging, creep, and fatigue, being excellent in long period durability reliability and sealing ability, and a resin part (a resin-molded product), such as a throttle chamber, having the actuator made of resin. SOLUTION: In an actuator made of resin provided at an internal part with two air chambers with a diaphragm located between upper and lower covers, a rubber ring 110 is contained in a rubber ring groove 111, and compressed by the outer surface of an upper cover rib 124 and the inner surface of a vertical wall 106a. The outer surface of the vertical wall 106a makes contact with the inner surface of a stopper 123. A weld part 120 is arranged at a part with which the base part of an upper cover flange 121 and the top part of a lower cover wall 106a make contact, welding between upper and lower covers is carried out in a direction extending orthogonally with the compression direction of the rubber ring 110.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin actuator for driving a rod attached to a diaphragm using a roll caulking or the like by a pressure difference between two air chambers provided in the actuator via a diaphragm.

[0002]

2. Description of the Related Art Conventionally, a valve that performs opening / closing control using the pressure in an intake passage or a negative pressure generated by a vacuum pump, for example, an internal combustion engine (engine) for an automobile
Parts such as the throttle valve of the throttle chamber for diesel engines and the driving power source such as the swirl control valve provided in the tail manifold are:
Metal actuators are widely used.

In a throttle chamber for a diesel engine, a throttle chamber solenoid operated by a pressure difference between a pressure in an intake passage of an internal combustion engine (engine) and a negative pressure generated by a vacuum pump, and an opening / closing of the throttle chamber solenoid are linked. The opening and closing of the throttle valve is controlled by an actuator that generates a driving force.

FIGS. 2 and 3 show an example of a metal actuator that has been widely used in the past. As shown in the figure, the metal actuator has a connector portion 7 and a projection portion 19 having a spring 8 wound on an inner surface thereof.
, A diaphragm 9 having a rubber ring 10 on its outer periphery, an air chamber (A) 14 formed by the diaphragm 9 and the upper lid 5, a diaphragm 9 and a lower lid 6
The diaphragm 9 receives the reaction force of the spring 8 when a pressure difference occurs between the two air chambers.

A rod 13 is attached to the center of the diaphragm 9 by roll caulking. Further, a rubber ring 10 provided on the outer periphery of the diaphragm 9
After the rubber ring 10 is inserted into the rubber ring groove 11 provided in the lower lid 6, the rubber ring 10 is compressed by caulking the upper lid 5 and the lower lid 6, and the air chamber (A) 14 and the air chamber (B) Fifteen
And the airtightness is secured.

Normally, the connector section 7 communicates via a rubber hose (not shown) with a throttle chamber solenoid operated by a pressure difference between a pressure in an intake passage of an internal combustion engine (engine) and a negative pressure generated by a vacuum pump. When the pressure in the air chamber (A) 14 of the actuator decreases, the diaphragm 9 moves in the direction of the arrow in FIG.
3 also moves in the direction of the arrow.

The relationship between the pressure in the air chamber (A) 14 and the amount of movement of the rod 13 can be arbitrarily set by the spring constant of the spring 8, and the throttle valve is provided with a fully closed state and a half open state. In some cases, a two-stage spring is used, or two connector parts are provided. In some cases, a drain hole 16 may be provided in the lower lid 6, and in this case, the pressure in the air chamber (B) 15 becomes atmospheric pressure.

Next, FIG. 1 shows an example of a throttle chamber for a diesel engine equipped with the above-described actuator. As shown in FIG. 1, the throttle chamber includes an actuator 1, a bracket 2, a screw 3, and a throttle body 4. The actuator 1 is provided with an upper lid and a lower lid having a connector part, and after inserting a rubber ring provided on an outer peripheral portion of the diaphragm into a rubber ring groove during assembly, a product is formed by caulking the upper lid and the lower lid. .

When the throttle chamber is made of resin, it is possible to integrally form the lower cover of the actuator, the bracket and the throttle body with resin, and to eliminate the screw. In this case, after the rubber ring provided on the outer peripheral portion of the diaphragm is inserted into the rubber ring groove provided on the integrally formed product of the lower cover, the bracket and the throttle body of the actuator, the upper cover and the lower cover are joined.

Various methods such as welding, self-tapping, bonding, and screwing are conceivable as a method of joining the upper lid and the lower lid of the actuator. Examples of the method include room temperature press fitting, heating press fitting, ultrasonic press fitting, and insert molding. Mostly, a resin molded product is used in which a metal collar is attached to an upper lid and a metal insert nut is attached to a lower lid by means of means and joined using screws, and is also excellent in long-term durability reliability.

[0011]

However, the conventional actuator and the throttle chamber made of resin use many metal parts such as collars, insert nuts, screws, etc., so that the advantages inherent in resinization are not obtained. There was a problem that it was difficult to obtain.

On the other hand, it is conceivable to join the upper lid and the lower lid of the actuator by means of ultrasonic welding, vibration welding, hot plate welding, electromagnetic welding or the like without using any metal parts. There is no possibility that the sealing function will be lost due to breakage of the welded part due to heat shock (heat cycle), heat aging, creep, fatigue, etc., or a decrease in the rubber ring compression ratio due to creep deformation of the upper or lower lid. (For reference, a cross-sectional view of a resin actuator (comparative example 1) in which an upper lid and a lower lid are joined by welding (when the pressure in the air chamber A = the pressure in the air chamber B))
Is shown in FIG. ).

The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to rupture a welded portion due to heat shock (heat cycle), heat aging, creep, fatigue and the like. Resin parts (resin molded products) such as lightweight resin actuators with excellent long-term durability reliability and sealability without causing seal failure and sealability, and throttle chambers with resin actuators
Is to provide.

[0014]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, the causes of the breakage of the welded portion between the upper lid and the lower lid and the occurrence of poor sealing are as follows (see FIG. 6). ). A tearing force acts on the welded end. Molten resin (burr) enters the rubber ring groove. Variations in the welding depth cause variations in the rubber ring compressibility.

The present inventors have further studied based on such knowledge, and made the compression direction of the rubber ring orthogonal to the welding direction of the upper and lower lids of the actuator, and provided a specific stopper on the upper lid. The inventors have found that the above-mentioned problems can be solved, and have completed the present invention.

That is, the resin actuator of the present invention comprises:
It has a connector part and a protrusion provided on the inner surface, and joins an upper lid with a spring wound around this protrusion and a lower lid with a rod inserted through a diaphragm having a rubber ring on the outer periphery With this configuration, two air chambers are provided inside, and the diaphragm is connected to the rod, and when a pressure difference occurs between the two air chambers, the rod is opposed to the reaction force of the spring. The upper lid has a rib protruding in the lower lid direction, and the rubber ring is compressed by the outer surface of the upper lid rib and the inner surface of the vertical wall of the lower lid, and The base of the upper lid and the top of the lower lid vertical wall are welded in a direction orthogonal to the compression direction of the ring, and the upper lid has a stopper protruding in the lower lid direction outside the upper lid ribs. With the inner surface of the stopper Wherein the serial and the outer surface of the lower cover vertical wall is in contact.

In a preferred embodiment of the resin actuator of the present invention, the lower lid has a rib projecting in the upper lid direction inside the lower lid vertical wall, and an inner side surface of the lower lid rib and the upper lid rib. The rubber ring is compressed with the outer surface of the lower lid rib, and the stopper of the upper lid is inserted and disposed between the lower lid rib and the lower lid vertical wall, and the outer surface of the lower lid rib and the inner surface of the stopper are formed. A gap is formed between the welded portion and the stopper by abutting and separating the outer surface of the stopper and the inner surface of the lower lid vertical wall from each other.

Further, a resin component according to the present invention is provided with the above-mentioned resin actuator.

In this specification, as shown in FIG. 5 (see 128 and 129 in FIG. 5), the vertical walls provided on the upper lid and the lower lid, the ribs, and the side surfaces on the actuator center side of the stopper are provided. The inner surface and the side surface on the actuator outer surface side will be referred to as the outer surface.

[0020]

In the resin actuator of the present invention employing the above-described structure, the compression direction of the rubber ring (= the reaction force direction of the rubber ring) is perpendicular to the welding direction of the upper and lower lids of the actuator, and the rubber ring compression ratio Has a structure that does not depend on the welding depth. Therefore, it is possible to prevent poor sealing due to insufficient rubber ring compression ratio, damage to the welded portion due to excessive rubber ring reaction force, and poor sealing due to this.

Further, by providing a stopper on the upper lid against the inner surface of the lower lid vertical wall or the lower lid rib, the tearing force acting on the welded portion is reduced, and the lower lid flange is formed. A reduction in the compression ratio of the rubber ring due to the creep deformation can be reduced, and a resin actuator excellent in long-term durability reliability and sealability can be provided.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a resin actuator according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 7 is an enlarged sectional view of a welded portion in one embodiment of the resin actuator of the present invention, and FIG.
FIG. 9 is an enlarged sectional view of a welded portion in another embodiment of the resin actuator of the present invention, FIG. 9 is an enlarged sectional view of a welded portion of the resin actuator of Comparative Examples 1 to 10, and FIG.
FIG. 3 is a graph showing the retention rate of welding strength and the occurrence of sealing failure after performing a heat shock test on the resin actuators of Example 1, Example 2, and Comparative Examples 1 to 10.

(Embodiment 1) FIG. 7 is an enlarged view showing the vicinity of a welded portion of an embodiment of the resin actuator of the present invention as described above. The parts are the same as the structure of the actuator shown in FIG.

In FIG. 7, a rubber ring 110 provided on the outer periphery of a diaphragm 109 has a rubber ring groove 111.
It is housed inside and is compressed by the outer surface of the upper lid rib 124 protruding from the upper lid flange 121 in the direction of the lower lid 106 and the inner surface of the vertical wall 106 a provided at the end of the lower lid flange 122. The outer surface of the vertical wall 106a is in contact with the inner surface of a stopper 123 provided outside the upper lid rib 124. Also, the welded portion 120 is located on the upper lid flange 1.
21 and the top of the lower lid vertical wall 106a are in contact with each other, and the upper lid 105 and the lower lid 106 are arranged in a direction orthogonal to the compression direction of the rubber ring 110 (rubber ring reaction force direction). Welding has been performed.

The method of welding the upper lid 105 and the lower lid 106 includes hot plate welding, vibration welding, ultrasonic welding, spin welding, electromagnetic welding, and the like, such as breakage or twisting of the rubber ring 110 provided on the outer periphery of the actuator. As long as it does not occur, any welding method may be adopted.

(Embodiment 2) In FIG. 8, a rubber ring 110 provided on the outer periphery of a diaphragm 109 is provided with an outer surface of an upper lid rib portion 124 of the actuator and a lower lid vertical wall 10.
It is compressed by the inside surface of the lower lid rib 125 protruding in the upper lid direction inside 6a. Further, the welded portion 120 is arranged at a portion where the base of the upper lid flange 121 and the top of the lower lid vertical wall 106a are in contact with each other, and in a direction orthogonal to the compression direction of the rubber ring 110 (rubber ring reaction force direction). The upper lid 105 and the lower lid 106 are welded.

In this embodiment, the stopper 123 is inserted between the lower cover rib 125 and the lower cover vertical wall 106a, and the outer surface of the lower cover rib portion 125 contacts the inner surface of the stopper 123. The outer surface of the stopper 123 is the vertical wall 1
The space 126 is formed apart from the inner side surface of the inner space 06a. By providing the gap 126, it is possible to reliably prevent the molten resin from flowing into the rubber ring groove 11 during welding. If the top of the stopper 123 and the base of the upper lid flange 121 are welded, the long-term durability reliability is further improved.

(Performance test) In order to confirm the effects of improving the long-term durability reliability and sealing properties of the resin actuators of Examples 1 and 2, the upper limit temperature was 130 ° C. (1 hour).
Minimum temperature: -40 ° C (1 hour), 100 cycles of a heat shock test were performed, and the welding strength retention rate of the resin actuator after the heat shock test (breaking load after heat shock test / breaking load before heat shock test) ) Was measured. In addition, the breaking load of the welded portion is shown in FIG.
The connector 107 and the rod 113 were held, and the measurement was performed using an autograph tester manufactured by Shimadzu Corporation at a crosshead speed of 1 mm per minute. A resin actuator having a welding strength retention of more than 80% was judged to be acceptable. FIG. 10 shows the obtained results.

On the other hand, the sealing property was confirmed by a water immersion leak test. A hose is connected to the connector 107 of the resin actuator, and the actuator is submerged in water.
The pressure was increased at atmospheric pressure + 1 atm, and the amount of leakage was measured. A resin actuator having a leak rate of 0.5 liter or less per minute was accepted. FIG. 10 shows the test results.

In performing the above performance test,
The material used for the resin actuators of Example 1 and Example 2 is PPS (polyphenylene sulfide resin) (trade name: Novops 770F1-X2) manufactured by Mitsubishi Engineering-Plastics Corporation. Further, the welding portion had a diameter of 50 mm and a welding width of about 0.8 mm, and welding was performed using an ultrasonic welding machine manufactured by Branson. The welding conditions were a welding depth of 0.6 mm (set value of the ultrasonic welding machine), a welding pressure of 500 kPa, a hold time of 20 seconds, a welding time of 0.60 seconds, and a peak power of 402J.

(Comparative Examples 1 to 10) 10 shown in FIG.
Resin actuators (Comparative Examples 1 to 10) having different types of welds and seals were prepared, and the above-described performance tests were performed. FIG. 10 shows the obtained results. The material of the actuator, the condition of ultrasonic welding, and the length (perimeter) of the welded portion in each example were the same as those in Examples 1 and 2.

In the resin actuators of Comparative Example 1, Comparative Example 4, Comparative Example 5, Comparative Example 6, Comparative Example 7, and Comparative Example 10, seal failure occurred. Also, the welding strength retention rate is
In Comparative Examples 4 and 8, which are the largest, about 5% of Examples 1 and 2 were used.
It was only 0%, and it was confirmed that it was difficult to guarantee long-term durability reliability with the resin actuators of Comparative Examples 1 to 10.

Although the present invention has been described in detail with reference to preferred embodiments, the present invention is not limited to these embodiments, and various modifications can be made within the scope of the present invention. For example, in the first and second embodiments, FIG.
It is possible to replace 121 in FIG. 8 with a lower lid flange and 122 with an upper lid flange. Further, the case where either the upper lid or the lower lid of the actuator is integrally molded with a resin such as a throttle chamber and an intake manifold is also included in the scope of the resin actuator of the present invention.

[0035]

As described above, according to the present invention, the compression direction of the rubber ring and the welding direction of the upper lid and the lower lid of the actuator are orthogonal to each other, and a specific stopper is provided on the upper lid. Light-weight resin actuator with excellent long-term durability and sealability without breaking welded parts or poor sealing due to shock (heat cycle), heat aging, creep, fatigue, etc., and a throttle chamber having a resin actuator It is possible to provide a resin component (resin molded product) such as

That is, by making the method of compressing the rubber ring (= the reaction direction of the rubber ring) orthogonal to the welding direction of the upper and lower lids of the actuator, the rubber ring compression ratio does not depend on the welding depth. In addition, by adopting a structure in which molten resin generated during welding does not flow into the rubber ring groove, poor sealing due to insufficient rubber ring compression ratio, damage to the welded portion due to excessive rubber ring reaction force, and sealing failure due to it are prevented. It became possible to prevent. Furthermore, by fitting the outer surface of the lower lid vertical wall or the outer surface of the lower lid rib portion to the inner surface of the stopper of the upper lid, the tearing force acting on the welded portion is reduced and the creep deformation of the lower flange portion is reduced. As a result, a reduction in the compression ratio of the rubber ring caused by the above can be reduced, and a resin actuator excellent in long-term durability reliability and sealability can be provided.

According to the first and second aspects of the present invention, while the compression direction of the rubber ring is the radial direction of the actuator, the upper lid and the lower lid are welded in the vertical direction of the actuator. Even if the depth is not constant, the compression ratio of the rubber ring hardly fluctuates. As a result, it has become possible to prevent poor sealing due to insufficient rubber ring compression ratio, damage to the welded portion due to excessive rubber ring reaction force, and poor sealing resulting therefrom.

According to the first aspect of the present invention, the outer surface of the lower lid vertical wall of the actuator is brought into contact with the inner surface of the stopper portion of the upper lid to reduce the reaction force of the rubber ring acting on the welded portion between the lower lid and the upper lid. In the invention of claim 2, by avoiding the tear mode, the outer surface of the lower lid rib portion of the actuator is brought into contact with the inner surface of the stopper portion of the upper lid, and the rubber ring reaction force acts on the welded portion of the lower lid and the upper lid. By adopting a structure that does not have such a structure, it is possible to prevent creep rupture of the welded portion. The above structure also has the effect of reducing or reducing creep deformation of the lower lid or the lower lid rib portion due to the rubber ring reaction force and a decrease in the rubber ring compression rate resulting therefrom, and provides a resinous actuator having excellent sealing properties. Became possible.

Further, according to the second aspect of the present invention, by providing a gap between the welding portion and the stopper, it is possible to completely prevent the molten resin generated at the time of welding from flowing into the rubber ring seal portion. It has become possible.

[Brief description of the drawings]

FIG. 1 is a top view of a conventional throttle chamber actuator.

FIG. 2 is a sectional view of a conventional metal actuator (air chamber A).
Pressure = at the pressure of the air chamber B).

FIG. 3 is a sectional view of a conventional metal actuator (air chamber A).
(At the time of the pressure of the air chamber B).

FIG. 4 is a cross-sectional view of the resin actuator (Comparative Example 1) (when the pressure in the air chamber A = the pressure in the air chamber B).

FIG. 5 is an enlarged cross-sectional view of a joint portion and a seal portion of the resin actuator of FIG.

FIG. 6 is an explanatory view showing a cause of a decrease in welding strength of a resin actuator and a generation of a sealing defect.

FIG. 7 is an enlarged sectional view of a welded portion in one embodiment of the resin actuator of the present invention.

FIG. 8 is an enlarged sectional view of a welded portion in another embodiment of the resin actuator of the present invention.

FIG. 9 is an enlarged sectional view of a welded portion of a resin actuator of Comparative Examples 1 to 10.

FIG. 10 is a graph showing the retention rate of welding strength after a heat shock test and the occurrence of defective sealing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Actuator 2 Bracket 3 Screw 4 Throttle body 5 Upper lid 6 Lower lid 7 Connector 8 Spring 9 Diaphragm 10 Rubber ring 11 Rubber ring groove 12 Caulking part 13 Rod 14 Air chamber A 15 Air chamber B 16 Drain hole 17 Seal part 18 Roll caulking Part 19 Projecting part 105 Upper lid 106 Lower lid 106a Vertical wall 107 Connector 108 Spring 109 Diaphragm 110 Rubber ring 111 Rubber ring groove 112 Joining part 113 Rod 114 Air chamber A 115 Air chamber B 116 Drain hole 117 Seal part 118 Roll caulking part 119 Projecting part 120 Welding part 121 Upper lid flange 122 Lower lid flange 123 Stopper 124 Upper lid rib 125 Lower lid rib 126 Void 128 Lower lid outer surface 129 Lower lid inner surface

Claims (3)

[Claims] 1. A connector comprising: a connector portion; a projection provided on an inner surface; an upper lid having a spring wound around the projection; a lower lid having a rod inserted therein; and a rubber ring on an outer periphery. By joining through a diaphragm, it has two air chambers inside, and the diaphragm is connected to the rod, and when a pressure difference is generated between the two air chambers, the reaction force of the spring is reduced. In a resin actuator that drives the rod in opposition, the upper lid has a rib protruding in the lower lid direction, and the rubber ring is formed by an outer surface of the upper lid rib and an inner surface of a vertical wall of the lower lid. A stopper that compresses and welds the base of the upper lid and the top of the lower lid vertical wall in a direction orthogonal to the compression direction of the rubber ring, and the upper lid projects in the lower lid direction outside the upper lid rib. This strike Resin actuator, characterized in that the path of the inner and outer surfaces of the lower cover vertical wall abuts. 2. The lower lid has a rib protruding in the direction of the upper lid inside the lower lid vertical wall, and the rubber ring is compressed by an inner surface of the lower lid rib and an outer surface of the upper lid rib. The stopper of the upper lid is inserted and arranged between the lower lid rib and the lower lid vertical wall, and the outer surface of the lower lid rib and the inner surface of the stopper are in contact with each other, and the outer surface of the stopper is The resin actuator according to claim 1, wherein a gap is formed between the welded portion and the stopper by separating the inner surface of the lower lid vertical wall from the inner surface. 3. A resin component comprising the resin actuator according to claim 1.