JPH0723602Y2 - Wastegate actuator for boost pressure control of internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a waste gate actuator for driving a supercharging pressure control valve (a waste gate valve) of a turbocharger, and more specifically to a diaphragm against vibration. And an actuator having improved durability.

[Prior Art] As a waste gate actuator (hereinafter simply referred to as an actuator) for driving a waste gate valve of a turbocharger, the inside of the case is divided by a diaphragm into a positive pressure chamber and an atmosphere chamber. The positive pressure chamber side, the atmosphere chamber side, and the shell are respectively arranged to clamp the diaphragm, and the rod having one end fixed to the diaphragm clamping portion by the shell is extended from the atmosphere chamber to the outside, and the diaphragm is moved from the atmosphere chamber side. It is widely known that a spring that presses toward the positive pressure chamber side is arranged between one of the shells and the case.

This actuator is used by connecting the other end of the rod to the waste gate valve and mounting it on a turbocharger, and the boost pressure generated by the operation of the supercharger is applied to the positive pressure chamber via a controller. Introduced into the system, the supercharging pressure and the atmospheric pressure are made to oppose each other on both sides of the diaphragm, and when the supercharging pressure exceeds the set value, the waste gate valve is operated to bypass the turbine exhaust pressure on the upstream side of the turbine. Excuse me.

By the way, since the case and rod of the actuator are connected and supported at different positions, the phases and amplitudes of the vibrations in the above two caused by the vibrations propagating from these during driving of the internal combustion engine and the turbocharger. different.
For this reason, the diaphragm having the rod fixed to the center may have an amplitude difference that causes friction with the shell on the surface perpendicular to the vibration direction. Then, due to the friction between the shell and the diaphragm, the diaphragm may be worn, and eventually may be damaged.

However, in a conventional general actuator, as shown in FIG. 6, the engagement and fixation of the rod 5 and the diaphragm 2 are carried out by interposing a flat washer 33 (Japanese Patent Laid-Open Publication No. Sho.
58-106205). That is, the rod 5 is above the rod 5.
Concentric with the main part of the large-diameter base stage 51, smaller-diameter middle stage
52 and an upper stage 53 having a smaller diameter are provided in a step shape. And
The diaphragm 52 and the central portions of the shells 3 and 4 are inserted into the interruption 52, and then the flat washer 33 is inserted into the upper stage 53, and then the upper stage 53 is caulked, and the caulking 531 causes the flat washer 33 to be inserted.
Is fixed, and the whole is engaged and fixed.

Further, as another conventional example of the engagement and fixation of the rod 5 and the diaphragm 2, there is one in which both are fixed by a snap-fit structure (Japanese Utility Model Publication No. 59-70061).

[Problems to be Solved] However, among the above-mentioned conventional examples, the former engaging and fixing means using a flat washer (Japanese Patent Laid-Open No. 58-106205) is easy to loosen because the flat washer has no elasticity. . Also, the latter one using the snap-fit structure (Shokai 59-700).
No. 61) has a complicated structure such as providing a groove portion for engaging the snap on the rod and requiring a snap having a special structure, resulting in high cost.

In view of such a problem, the present invention intends to provide a wastegate actuator for supercharging pressure control of an internal combustion engine, which secures the engagement and fixation of the diaphragm holding portion and the rod by the shell and improves the durability of the diaphragm. It is a thing.

[Means for Solving Problems] The present invention provides a case, a diaphragm arranged to divide the inside of the case into a positive pressure chamber and an atmosphere chamber, and a diaphragm arranged on the positive pressure chamber side and the atmosphere chamber side of the diaphragm. And a rod having the diaphragm sandwiched between them, and a rod having one end engaged and fixed to the diaphragm sandwiching portion by the shell and extending from the atmosphere chamber to the outside. The other end of the rod is a waste gate valve of the supercharger. A wastegate actuator for supercharging pressure control of an internal combustion engine to be connected to a rod, wherein a rod having an outer diameter larger than an outer diameter of the rod at one end of the rod, and a rod having a diameter smaller than the rod. And the free end portion of the shell is penetrated by the free end portion so that one outer side surface of the shell is brought into contact with the base stage. The gripping portion is formed of a material having a relatively higher material hardness than that of the shell, and has a plurality of teeth around the periphery of the base having a hole for mounting the free end of the rod. Is formed so as to project outward in the radial direction of the rod, and each tooth tip of the tooth is formed by bending so as to project at a predetermined height from the one surface of the base at the tip of each tooth. The washer is arranged with the tip of the tooth abutting against the other outer surface of the shell, and the tip of the washer is directed to the base of the washer at the free end of the rod fitted with the washer. Formed by molding, located near the tip of each tooth of the washer with respect to the rod, at a position where each tooth tip has a repulsive force due to elasticity, and at a position far from the periphery of the hole formed in the base. Takashi with edge Portion applies a compressive force to the washer toward the diaphragm sandwiching portion by the shell to cause the tooth tip formed by the washer to bite into the outer side surface of the shell that abuts against the tooth tip and the repulsive force due to the elasticity of the tooth tip. The diaphragm holding portion by the shell is engaged and fixed to the rod in a state where the above is held, so that the sliding between the shell and the washer is prevented and the engagement and fixing is strengthened.

[Embodiment] FIG. 5 is a partially cutaway front view of an embodiment of the present invention.
The case 1 is divided into a positive pressure chamber A and an atmospheric chamber B by a diaphragm 2 in which two halves are joined by caulking at a cylindrical wall portion and a peripheral edge 21 is fixed to the caulking portion. The positive pressure chamber A is a chamber hermetically sealed by the upper half of the case 1 and the diaphragm 2, and the supercharging pressure generated by the supercharger via a nozzle 10 communicating with a controller (not shown). Air is introduced. The atmosphere chamber B communicates with the outside air. At the center of the diaphragm 2, a shell 3 formed of a flat plate-like material is brought into contact with the positive pressure chamber A side, and a shell 4 having substantially the same shape as the shell 3 is brought into contact with the atmosphere chamber B side. One end of the rod 5 is engaged and fixed to a sandwiching portion of the diaphragm 2 by the shells 3 and 4 of the rod 5 through a washer 7 as described later.
The other end of the rod 5 extends from the atmosphere chamber B to the outside of the case 1, and the other end is connected to a waste gate valve (not shown) through a bolt hole 50. In the atmosphere chamber B, a coil spring 61 centered on the rod 5 is arranged between the shell 4 and the lower half of the case 1, and the diaphragm 2 is contracted to the positive pressure chamber A via the shell 4. Energize in the direction you want to.

According to such a configuration, both sides of the diaphragm 2 are
On the other hand, the supercharging pressure in the positive pressure chamber A acts on the other surface by the atmospheric pressure in the atmospheric chamber B and the sum of the elastic forces of the coil springs 61, so that the pressure in the positive pressure chamber A becomes the atmospheric pressure. When the force pressing the diaphragm 2 from the chamber B side is overcome, the rod 5 is activated,
Activate the weight atgate valve. Incidentally, reference numeral 62 in FIG.
Is a bracket fixed to the case 1, and 63 is a seal rubber.

FIG. 1 shows the details of the construction in which the sandwiching portion of the diaphragm 2 is engaged and fixed to one end of the rod 5 by the washer 7 by the shells 3 and 4. Similar to the prior art, a base 51 having a diameter larger than the main part is formed at the end of the rod 5 concentrically with the main part of the rod 5, and the base 51 is provided at the tip of the base 51. Subsequently, the free end portion including the small-diameter middle stage 52 and the smaller-diameter upper stage 53 following the middle stage 52 is formed in a step shape.
A diaphragm 2 and a shell are provided in the middle stage 52 of the rod 5.
The holes formed in the central portions of the holes 3 and 4 are fitted, and the holding portion of the diaphragm 2 held by the shells 3 and 4 is supported by the base 51. Next, a hole 73 formed in the center of the washer 7 in the upper stage 53
Fit together. As shown in FIGS. 2 and 3, the washer 7 used in this embodiment is a flat base having a plurality of teeth 70 radially formed at equal intervals on the outer periphery of an annular base portion 74 having a hole 73 formed in the center. It is made of a plate-shaped material made of an elastic material, and has a planar shape formed like a gear. Each of the teeth 72 is provided on both side edges extending in the radial direction from the center of the washer 7, a tooth tip 71 twisted upward with respect to the plate surface on one side edge, and a plate surface on the other side edge. On the other hand, tooth tips 72 that are twisted downward are formed by projecting from the base portion 74 in the up-down direction, respectively, so that the tooth tips 71 and 72 both have a repulsive force due to their elasticity. As clearly shown in FIG. 3, at least downwardly, the tip of the twisted tooth tip 72 is made to project from the plate surface of the base portion 74 by a height h in the direction perpendicular to the plate surface. These twisted tooth tips 71, 72 are not limited to being formed only on the side edge portions of the tooth 70, but may be formed by twisting the entire tooth 70 as shown in FIG. When the holes 73 of the washer 7 of the upper stage 53 are fitted, the tooth tips 71, 72 formed on the teeth 70 of the washer 7 are inserted.
One of the two is shown in FIG.
Comes into contact with the outer surface of the shell 3 located on the positive pressure chamber A side. Here, the upper stage that constitutes the free end of the upper stage 53 of the rod 5
By crimping the end portion of 53 toward the base portion 74 of the washer 7, the outer peripheral edge of the rod is closer to the rod, and the tooth tips 71 and 72 form the washer 7 closer to the tips of the teeth of the washer 7. The caulking portion 531 is formed at a position having a repulsive force due to the elasticity of the elastic material, and located farther than the peripheral edge of the hole formed in the base portion 74 of the washer 7. The caulking portion 531 is pressed against the washer 7 by the force applied at the time of molding.
The base portion 74 of the isher 3 is pressed against the surface of the shell 3, but its outer peripheral edge does not reach the farthest tip of each tooth of the washer 7 with respect to the rod, and thus protrudes outward from the outer peripheral edge of the caulking portion 531. The tooth tip 72 facing the shell 3 located at the tip of each tooth of the washer 7 is formed by the elastic reaction force of the tooth tip 72 itself and the pressure contact force of the caulking portion 531 that presses the washer 7. While being strongly pressed against the shell 3, the sandwiching portion of the diaphragm 2 by the shells 3 and 4 is engaged and fixed to the rod 5 via the washer 7. That is, if the height of the rod 5 of the middle step 52 in the longitudinal direction is H, when the base 74 of the washer 7 abuts on the annular surface of the middle step 52 having a diameter larger than that of the upper step 53, the tooth tip 72 comes out of the surface of the base 74. Protruding height h
Since it overlaps with the height H, if the thickness of the sandwiching portion of the diaphragm 2 by the shells 3 and 4 is set to the same dimension as or extremely close to the height H, the sandwiching portion will have a tooth tip.
Since the clamping force due to the elasticity of 72 acts, the engagement fixation is strengthened, and the durability against temperature change is also improved.

Further, in the embodiment, the shells 3 and 4 are press-molded using aluminum as the material, and the washer 7 is SPCC as the material.
When the tooth tips 71 and 72 are formed and hardened after punching using a steel plate, the tooth tips 72 are compression-engaged with the shell 3 due to the formation of the caulking portion 531 and bite into the shell 3. Locked in. As a result, the sum of the repulsive force due to the elasticity of the diaphragm 2 itself and the repulsive force due to the elasticity of the tooth tips 72 becomes the axial fixing force of the rod 5, and the engagement between the nipping portion of the diaphragm 2 and the rod 5 by the shells 3 and 4. The fixation becomes stronger, and the vibration does not cause sliding between the shell 3 and the washer 7, so that the sandwiching portion of the diaphragm 2 by the shells 3 and 4 is extremely stable, and the caulking portion is formed. With the formation of 531, rotation about the shaft of the rod 5 does not occur between the holding portion and the rod 5, and the rod 5 does not rotate.
With respect to the tips of the teeth of the washer 7 protruding outward from the outer peripheral edge of the caulking portion 5,31, the contact point of the tooth tip 72 of each tooth 70 with the shell 3 is set as a free end, and the caulking portion 531 and the shell 3 are separated from each other. By providing a cantilever shape in which the portion sandwiched between them serves as a fixed portion, when the impact force due to vibration or the like is transmitted to the rod 5, the tooth tips 72 at the tip portion of the cantilever shape.
Due to the elastic deformation of, the impact force is relaxed and transmitted to the diaphragm.

As shown in the above embodiment, if the material hardness of the shell is lower than the material hardness of the washer, in other words, the material forming the washer has a relatively higher material hardness than the material forming the shell. In this case, the tooth tip of the washer digs into the outer surface of the shell that abuts against it, stabilizes the positional relationship between the rod and the shell, and prevents relative rotation between the clamping portion of the diaphragm and the rod by the shell. As a specific embodiment in which the material hardness between the two is different, the shell is made of aluminum, the washer is made of steel, and the shell is made of synthetic resin, and the washer is made of steel or spring steel. Each of them may be configured by one of them.

In the above-described embodiment, the washer 7 is described as having the tooth tips 71 that are radially protruded from the base portion 74 and have the tooth tips 71 that are twisted upward and the tooth tips 72 that are twisted downward at both side edges. The tips 71 and 72 may both be formed by protruding from one surface of the base portion 74. The tip 71 twisted upward in FIG.
This is because, in the case of the present embodiment, there is an advantage that any surface of the washer 7 can be attached to the shell 3 at the time of assembling, but the tooth tips 71 are not useful for engaging and fixing after the assembling. . Further, instead of the washer 7 having the gear shape shown in the drawing, a notch is provided in the diametrical direction from the peripheral edge of the annular washer to form a plurality of teeth on the peripheral edge of the base portion, and the edge portion formed by the notch is directed toward the shell. Bently formed tooth tips may be formed.

[Operation and Effect of the Invention] According to the present invention, the diaphragm that divides the case into the positive pressure chamber and the atmospheric chamber is provided with shells on the positive pressure chamber side and the atmospheric chamber side, respectively, to sandwich the diaphragm. When engaging and fixing one end of the rod to the sandwiching portion, a base stage having an outer diameter larger than the outer diameter of the rod and a free end having a smaller diameter than the base stage are formed at the one end of the rod. The free end portion penetrates the diaphragm holding portion by the shell to bring the outer surface of the one shell into contact with the base step, and a plurality of holes are formed on the periphery of the base portion in which the hole for mounting the free end portion of the rod is formed. A washer having individual teeth protruding outward in the radial direction of the rod is brought into contact with the outer surface of the other shell, and the free end of the rod is swaged by directing its tip toward the base of the washer. Formed part Due to
The diaphragm holding portion by the shell is engaged and fixed to the rod in a state in which the tip of the washer having the repulsive force due to its own elasticity formed on the tooth of the washer is engaged with the outer surface of the shell that abuts against the tooth. .

The washer is made of a material having a relatively higher material hardness than the material of which the shell is made, and the tip of each tooth is formed by bending so as to project from the one surface of the base portion. It is formed on the tip of the tooth with a repulsive force, and the caulking portion has its outer peripheral edge with respect to the rod,
Since each tooth tip is closer to the tip of each tooth of the washer and has a repulsive force due to elasticity, and is formed so as to be far from the peripheral edge of the hole formed in the base portion, Each base of the washer, which is located at the periphery of the hole of the washer, is pressed against the outer surface of the other shell due to the formation of the caulked portion, and is exposed to the outside of the rod in the radial direction from the outer peripheral edge of the caulked portion. At the tip of the tooth, the repulsive force due to the elasticity of the tooth tip of each tooth is caused by the contact of the tooth tip with the outer surface of the shell and the bending force caused by the outer peripheral edge of the caulking portion pressing down each tooth. Based on the above, the washer is pressed against the outer surface of the other shell with a strong force, and due to the relative difference between the strong force and the material hardness, the tooth tip of the washer has a relatively high material hardness. Bite into the surface of the lower shell, which causes the washer and the shell And preventing the accurately relative rotation between, even more impact force is One Kuwawa the rod by the operation of the vibration or actuators propagated from the outside,
The tip end of each tooth of the washer exposed radially outward from the outer peripheral edge of the rod-engaging portion is such that the caulking portion and the shell are radially inward from the outer peripheral edge of the rod-engaging portion. By forming a cantilever shape with the portion sandwiched between them as a fixed portion and the free end at the contact point of the tooth tip of each tooth with the shell, the tip of each tooth is set at a predetermined distance from the base of the tip of each tooth. The protrusion of the teeth causes elastic deformation while maintaining the biting position on the outer side surface of the shell, and absorbs the impact force to the shell and the diaphragm, thereby sliding on the diaphragm. The durability of the diaphragm against vibration can be improved without applying excessive pressure and the elasticity of the tooth tip and the elasticity of the diaphragm that are formed by protrusion by bending are engaged and fixed. It becomes the axial direction of the fixing force of Oite rod, a robust engagement fixation with elastic obtained.

As described above, according to the present invention, a washer having a tooth tip formed by bending is applied to the engaging and fixing of the diaphragm holding portion and the rod by the shell, and a compressive force is applied to the tooth washer to the outer surface of the shell. Since it is intervening in a closed state,
Even when vibrations having different phases and amplitudes are transmitted to the case and the rod during the operation of the internal combustion engine and the supercharger, the engagement and fixation are reliable and the relative movement between the diaphragm and the shell is appropriate. It is accurately prevented, so friction and wear between the diaphragm and the shell are greatly reduced,
While preventing damage to the diaphragm,
It is possible to provide a low-cost and highly reliable wastegate actuator with improved durability against temperature changes.

[Brief description of drawings]

1 to 5 show an embodiment of the present invention. FIG. 1 is a sectional view of a diaphragm fixing portion, FIGS. 2 and 3 are plan and side views of a washer, and FIG. 4 is an upper side of a rod. FIG. 5 is an overall view of the waste gate actuator, and FIG. 6 is a cross-sectional view of the diaphragm fixing portion of the conventional actuator described above. 1 ... Case, 2 ... Diaphragm, 3,4 ... Ciel,
5 ... Rod, 61 ... Spring, 7 ... Washer, 71, 72
...... Tooth tip.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-58-106205 (JP, A) Actual opening S58-24424 (JP, U) Actual opening Shou-52-116660 (JP, U) Actual opening 15- 3710 (JP, Y1) Patent 111794 (JP, C2)

Claims (3)

[Scope of utility model registration request] 1. A case, a diaphragm which divides the case into a positive pressure chamber and an atmosphere chamber, and a diaphragm which is arranged on the positive pressure chamber side and the atmosphere chamber side of the diaphragm to sandwich the diaphragm. It is made up of a shell and a rod having one end engaged and fixed to the diaphragm holding portion by the shell and the other end extending from the atmosphere chamber to the outside of the case. The other end of the rod is a waste gate of the supercharger. In a wastegate actuator for supercharging pressure control of an internal combustion engine to be connected to a valve, at one end of the rod, a base having an outer diameter larger than the outer diameter of the rod, and a smaller diameter than the base. A free end portion, and the free end portion penetrates the diaphragm holding portion by the shell to bring one outer surface of the shell into contact with the base stage. The ram holding portion is formed of a material having a relatively higher material hardness than the material forming the shell, and a plurality of teeth are formed on the periphery of the base portion having a hole for mounting the free end portion of the rod. Is formed so as to project outward in the radial direction of the rod, and each tooth tip of the tooth is formed by bending so as to project at a predetermined height from the one surface of the base at the tip of each tooth. The washer is arranged by abutting the tip of the tooth against the other outer surface of the shell, and the tip of the washer is directed to the base of the washer at the free end of the rod fitted with the washer. An outer peripheral edge formed by molding, which is located near the tip of each tooth of the washer and at a position where the tooth top has a repulsive force due to elasticity and far from the peripheral edge of the hole formed in the base. Equipped with The squeezing portion applies a compressive force to the washer toward the diaphragm holding portion by the shell to cause the tooth tips formed on the washer to bite into the outer side surface of the shell that abuts against the washer and repulsive force due to elasticity of the tooth tips. A wastegate actuator for supercharging pressure control of an internal combustion engine, characterized in that the diaphragm holding portion by the shell is engaged and fixed to the rod in a state of holding. 2. The waste gate for controlling supercharging pressure of an internal combustion engine according to claim 1, wherein the shell is made of aluminum and the washer is made of steel.・ Actuator. 3. The internal combustion engine according to claim 1, wherein the shell is made of a synthetic resin material and the washer is made of one of steel and spring steel. Wastegate actuator for controlling supercharging pressure of engine.