JP2000145470A - Shift lever for waste gate valve of turbocharger and manufacturing method for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a shift lever for a waste gate valve of a turbocharger with high efficiency by eliminating a cutting process for a heat-resisting metal which is a material hard to cut. SOLUTION: By a header machine in a header working process a flange part 15 is formed like a partition at the middle of a starting material in the form of a round bar. Both ends of the starting material are deformed into predetermined shapes by cold plastic working to reduce sizes. Through this process a stem part 13 is finished and a swing part 14 is half-finished. Through a bending/pressing process the swing part 14 under a half-finished condition is bent roughly into a bent shape. Then a range from the side of the swing part 14 to a valve support part 18 is plastically deformed into a flat shape by press working. Through a piercing process a hole is opened in the valve support part 18. Through those processes a shift lever is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a shift lever in a wastegate valve mounted on a turbocharger used in an automobile engine or the like, and more particularly to a novel method for manufacturing the shift lever without cutting. The present invention relates to a shift lever in a wastegate valve and a method for manufacturing the same.

[0002]

BACKGROUND OF THE INVENTION A turbocharger is known as a supercharger used as a means for increasing the output and performance of an automobile engine. In this engine, the turbine is driven by the exhaust energy of the engine, and the output of the turbine rotates the compressor to bring the engine into a supercharged state more than the natural intake. In such a turbocharger, the turbine may receive energy of excessive exhaust gas depending on the rotational state of the engine.Therefore, when such excessive exhaust gas is supplied, that is, the engine is substantially rotated at a high speed. In such a case, excess exhaust gas is bypassed without being used for driving the turbine, and is exhausted as it is. A wastegate valve is used to open such a bypass path, but equipment around the turbocharger, such as the wastegate valve or a shift lever that drives the wastegate valve, receives exhaust gas almost directly and is close to several hundred degrees Celsius. Because of being placed in a high-temperature atmosphere, extremely high heat resistance is required. However, materials having such heat resistance, for example, JIS standard, SUS310S material, are excellent in heat resistance, but are extremely difficult to machine such as cutting. It requires extremely elaborate work and time, and there are certain limits to increasing its production efficiency.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of such a background, and by eliminating cutting work even for such a refractory metal material which is difficult to cut. This is an attempt to develop a new method that can process the shift lever of a wastegate valve of a turbocharger with high efficiency.

[0004]

According to a first aspect of the present invention, a shift lever in a wastegate valve of a turbocharger according to the first aspect of the present invention includes a stem portion constituting a rotating shaft and a swinging bent bent into one end connected to one end of the stem portion. Part and a valve body support part having a pin hole for mounting a valve at the tip of the swing part, wherein the stem part is formed by cold plastic deformation of a rod-shaped starting material by header processing. It is characterized by having been done.

According to a second aspect of the present invention, the shift lever in the wastegate valve of the turbocharger has a stem portion formed by the header processing having a surface roughness of Ra 1.2 or less, in addition to the requirement of the first aspect. In addition, the shaft accuracy is processed to 20 μm or less.

The shift lever in the wastegate valve of the turbocharger according to a third aspect of the present invention is the same as the first or second aspect, wherein the starting material is
It is characterized by being a heat-resistant stainless steel.

According to a fourth aspect of the present invention, there is provided a method for manufacturing a shift lever in a wastegate valve of a turbocharger, wherein a round bar-shaped starting material is formed into a partition at an intermediate portion by a header machine in a header processing step. Then, both sides thereof are cold-plastically deformed so as to be squeezed into a predetermined shape, the stem portion is completed by this process, the oscillating portion is in an intermediate working state, and then the oscillating portion in the intermediate working state in a bend press working process Is bent substantially into a bent shape, and furthermore, the range from the side surface of the swinging portion to the valve body support is plastically deformed flat by press working, and then a hole is formed in the valve body support in the piercing process by piercing. It is characterized by being processed.

According to a fifth aspect of the present invention, in the method of manufacturing a shift lever for a wastegate valve of a turbocharger, in addition to the requirement of the fourth aspect, the processing of the stem in the header processing has a surface roughness of Ra1.2. And the axis accuracy is set to 20 μm or less.

According to the present invention, even a shift lever in a wastegate valve to which a heat-resistant material which is difficult to cut is applied does not employ any cutting work, and a very high-performance product can be obtained with high efficiency.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be specifically described based on the illustrated embodiments. First, the shift lever of the wastegate valve according to the present invention will be described, and then a method of manufacturing the shift lever will be described in order from the starting material to the completion of the product. 1 and 2, reference numeral 1 denotes a wastegate valve, which includes a shift lever 10 to which the present invention is applied, and is attached to a turbocharger 2. First, the peripheral devices of the turbocharger 2 will be described. As is well known, this is one of the superchargers for improving the combustion efficiency of the engine E.
And an intake pipe 5 connected to the air cleaner 4, and a silencer 7 is further connected to the exhaust side of the turbocharger 2 via a catalytic converter 6.

The turbocharger 2 is provided with a turbine 21 for receiving exhaust gas G from the exhaust pipe 3 to a casing 20 thereof, and a compressor 22 driven by the turbine 21 is provided on the intake pipe 5 side. ing. An exhaust inlet 23 formed on the turbine 21 side is connected to the exhaust pipe 3, and the exhaust inlet 23 is connected to the main inlet 23.
A is formed so as to branch into A and a bypass inlet 23B. The waste gate port 2 is provided on the partition wall 24 between the main inlet 23A and the bypass inlet 23B.
The wastegate port 25 is opened and closed by the wastegate valve 1 which is an object of the present invention. And the main inlet 23
The turbine 21 is driven by the exhaust gas G from A, and the exhaust gas G finally joins the path from the bypass inlet 23B and is exhausted from the exhaust outlet 26 to reach the catalytic converter 6.

Further, a shift linkage 27 for driving the wastegate valve 1 and an actuator 28 for driving the shift linkage 27 are provided on the side of the turbocharger 2. The actuator 28 operates by sensing the intake pressure of the engine with a diaphragm or the like, for example, as schematically shown in FIG.

The wastegate valve 1 attached to the turbocharger 2 having such a structure will be described in more detail. As an example, as shown in FIG. 3, the wastegate valve 1 has a shift lever 10 having a substantially L-shape as a whole, and a valve body 11 at one end thereof.
It is relatively loosely mounted through the two. The shift lever 10 has a stem 13 forming a rotation shaft,
It has a swing portion 14 bent in a vent shape with respect to the stem portion 13, and a flange portion 15 is formed between the both. The end of the stem 13 is provided with a linkage receiving end 16 having a smaller diameter.

The oscillating portion 14 has a vent portion 17 which is gently bent by about 90 °, and a valve body support portion 18 formed continuously at the tip thereof. The vent portion 17 and the valve body supporting portion 18 have a state in which the vent portion 17 is flattened and crushed, and the vent portion 17 is a vent crushed portion 17A in which the side surface of the circular cross section is further slightly pushed in. On the other hand, the valve body supporting portion 18 has a state in which the surface shape viewed from the side surface is expanded with further crushing. The pin 1 is provided on the valve body support portion 18.
2 has a pin hole 19 for receiving the valve body 11. The shift lever 10 is most preferably made of a heat-resistant stainless steel, for example, JIS standard, SUS310S, or the like. As shown in FIG. 4A, the stem 13 preferably has a surface roughness of less than Ra1.2 and a shaft accuracy of less than 20 μm.

The shift lever 10 in the waste gate valve 1 of the present invention has the above-described shape, and is manufactured while sequentially taking steps shown in FIGS. (1) Supply of Starting Material As the starting material W, since the shift lever 10 is required to have sufficient heat resistance, as described above, for example, SU
A heat-resistant stainless steel material such as S310S is preferable. The starting material W is selected in consideration of the dimensional specifications of the product and the state of plastic deformation of the material.
As shown in (a), a round bar-shaped material is applied.

(2) Header processing step The round bar-shaped material is subjected to cold plastic deformation by header processing to obtain an intermediate product. In the following description, the intermediate material being processed will be described as a symbol W1.

(2) -i. Oscillating Part Forming Step First, a part that constitutes the oscillating part 14 is formed on one end side of the starting material W as shown in FIG. The header processing is performed so that the diameter of the starting material W is substantially reduced to some extent, and a step is formed between the starting material W and a portion where the flange portion 15 is formed by post-processing.

(2) -ii. Processing of Stem Portion Subsequently, a process of narrowing down a portion constituting the stem portion 13 to a small diameter by header processing is performed. At that time, FIG.
In the embodiment shown in (c) and (d), the number of steps of the header processing is determined from the relationship between the diameter of the starting material W and the diameter required for the product, although the narrowing down is performed in two stages.
At this stage, the diameter of the stem 13 is substantially set, and a desired diameter is obtained. The flange 15 is formed by this step.

(2) -iii. Processing of Linkage Receiving End In this state, a linkage receiving end 16 having a smaller diameter is formed on the distal end side of the stem portion 13 by header processing as shown in FIG.

(3) Bend / press working step (3) -i. Vent Forming Step First, as shown in FIG. 6A, a straight round bar portion serving as the vent portion 17 is bent so as to be bent at a predetermined angle. This is performed by a bent shape, but a roller or the like that can freely roll is disposed at a contact portion or the like between the bent mold and the intermediate material W1 so that the bending process can be performed smoothly. preferable. In addition, if this bending process is necessary, if a single bending process is not enough, or if a single bending process makes it impossible to process, etc. Obtain a bent state.

(3) -ii. Next, as shown in FIG. 6B, a pressing process is performed to crush the side surface of the entire oscillating portion 14. Thereafter, as shown in FIG. 6C, the tip of the swinging portion 14 is further flattened to form a space for forming the pin hole 19.

(4) Piercing Step Thereafter, as shown in FIG. 6D, a pin hole 19 is formed by a piercing punch P. In such a formed state, the surface roughness of the stem portion 13 is suppressed to approximately Ra1.2 or less and the axial accuracy is suppressed to approximately 20 μm or less. By the way, even in this case, the rough surface formed on the stem portion 13 is in a state where it is all recessed from the reference surface as shown in an enlarged view in FIG. No obstacles. Incidentally, in the case of cutting, for example, in the case of this kind of difficult-to-cut material, the axis accuracy is ± 5/100 mm to ± 6/1.
Variation in the range of 00 mm, and the variation is shown in FIG.
As shown in FIG. 2B, the convex portion and the concave portion have a shape that is repeated with respect to the standard surface.
In the relationship with the bearing part for receiving the bearing 3, the clearance must be sufficiently secured, and as a result, the clearance may be loose, which may hinder the improvement of the performance of the whole product.

(5) Assembling Process of Valve Body Incidentally, it is preferable that the valve body 11 be formed into a hat shape by blanking by a fine blanking method and pressing. Since the pin 12 is set so as to pass through the pin hole 19 in the valve body 11 and the pin hole 19 in the shift lever 10, the both ends thereof are caulked to attach the valve body 11 to the valve body support portion 18 of the shift lever 10. is there. In this attachment, it is preferable to attach the valve body 11 in a relatively loose state so that the valve body 11 can be in close contact with the waste gate port 25 in the partition wall 24.

[0024]

According to the present invention, the shift lever in a wastegate valve to which a heat-resistant material, which is difficult to cut, is applied without using any cutting work, has a very high construction. This has the effect that a product with high performance can be obtained with high efficiency.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a wastegate bubble and a turbocharger incorporating a shift lever of the present invention.

FIG. 2 is an explanatory diagram schematically showing peripheral devices of a turbocharger.

FIGS. 3A and 3B are a front view (a) and a side view (b), respectively, showing a wastegate valve incorporating the shift lever of the present invention in a partially cutaway manner.

FIG. 4 is an enlarged view showing a difference in surface roughness of a stem portion processed by two different methods.

FIG. 5 is an explanatory diagram showing stepwise how a stem portion and a swinging portion of a shift lever are narrowed down and formed.

FIG. 6 is an explanatory view showing stepwise how a bent portion and a pin hole are formed in a shift lever.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Waste gate valve 2 Turbocharger 3 Exhaust pipe 4 Air cleaner 5 Intake pipe 6 Catalytic converter 7 Silencer 10 Shift lever 11 Valve body 12 Pin 13 Stem section 14 Swing section 15 Flange section 16 Linkage receiving end 17 Vent section 17A Vent crush Portion 18 Valve body support portion 19 Pin hole 20 Casing 21 Turbine 22 Compressor 23 Exhaust inlet 23A Main inlet 23B Bypass inlet 24 Partition wall 25 West gate port 26 Exhaust outlet 27 Shift linkage 28 Actuator E Engine G Exhaust gas P Pierce punch W Starting material W1 Intermediate material

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Claims (5)

[Claims] 1. A valve body support having a stem portion constituting a rotation shaft, a swing portion bent into a vent shape connected to one end of the stem portion, and a pin hole for mounting a valve at the tip of the swing portion. A shift lever in a wastegate valve of a turbocharger, wherein the stem portion is formed by cold plastic deformation of a bar-shaped starting material by header processing. 2. The stem formed by the header processing has a surface roughness of Ra1.2 or less and an axial accuracy of 20 μm.
2. The shift lever according to claim 1, wherein the shift lever is formed to have a diameter of not more than m. 3. The shift lever according to claim 1, wherein the starting material is a heat-resistant stainless steel material. 4. In a header processing step, a round bar-shaped starting material is cold-plastically deformed so that both sides thereof are squeezed into a predetermined shape in a state where a flange portion is formed in a middle portion by a header machine. In addition to completing the stem part, setting the swinging part in the intermediate processing state, then bending the swinging part in the intermediate processing state into a substantially bent shape in the bend press process, and supporting the valve body from the side part of the swinging part Production of a shift lever in a wastegate valve of a turbocharger, in which a range up to a portion is plastically deformed into a flat shape by press working, and then a hole is formed by piercing in the valve body supporting portion in a piercing process. Method. 5. The shift in a wastegate valve of a turbocharger according to claim 4, wherein the processing of the stem portion in the processing of the header has a surface roughness set to Ra1.2 or less and an axial accuracy set to 20 μm or less. Manufacturing method of lever.