KR20150001976A - Cam shaft apparatus, shaft and its manufacturing method - Google Patents

Abstract

The present invention relates to a cam shaft apparatus which enables the manufacture of a product which is ultra-light and has high toughness by coupling a shaft and a lobe of the cam shaft device which are male and female, or vice versa; wherein the shaft is formed by extruding an aluminum material, and the lobe is formed of an iron-based material, an aluminum alloy, and an aluminum composite material, or by integrally forging a shaft part and a lobe part wherein the shaft part and the lobe part are made of aluminum. The cam shaft apparatus may comprise: the shaft; the lobe installed in the shaft; and an engaging member installed between the shaft and the lobe in order to fixate the lobe to the shaft.

Description

TECHNICAL FIELD The present invention relates to a cam shaft apparatus, a shaft and a manufacturing method thereof,

The present invention relates to a camshaft device, a method of manufacturing a shaft and a camshaft device, and more particularly, to a method of manufacturing a camshaft device by extruding a shaft of a camshaft device with an aluminum material, A camshaft device which is combined with a male or female or male and female so as to manufacture an ultra-light and high-toughness product, and a method of manufacturing a shaft and a camshaft device.

Generally, a camshaft device is a component that serves to open and close an intake valve and an exhaust valve in accordance with rotation of an internal combustion engine, and adjusts an opening and closing timing of an intake and exhaust valve of a shaft serving as a rotary shaft, A lobe, and a journal serving as a rotating stator.

Since the opening and closing timings of the valves and the lifts are different from each other even if the curvature of the camshaft lobe is slightly changed, the performance of the engine is influenced by the valve opening and closing timing. Therefore, the conventional lobes and shafts are mainly used for cast iron and cast steel Iron-based material.

In the case of casting, casting of gray cast iron and spheroidizing graphite cast iron is performed, and then heat treatment such as high frequency and nitriding is applied to the lobe of cast iron for the casting, forging, welding and powder metallurgy. However, in order to minimize weight loss and to minimize casting defects, it is necessary to use centrifugal casting in a hollow state to minimize casting defects, The casting method is applied, but it is less competitive than the hollow method by powder.

In the case of the forging process, the advantage of the excellent mechanical properties is required. However, the weight of the casting camshaft device needs to be improved in the same manner as the casting camshaft device. Is less competitive than the hollow type.

Currently, most of the camshaft devices are made of hollow steel pipe, the process of making the powder lobes to be bonded during the powder sintering process, and the method of joining the journals through brazing are the most applied, and more than 30% However, even in the case of the hollow powder sintering type, weight reduction and manufacturing cost reduction are required for the downsizing of the engine and the variable valve timing (VVT) control of the engine.

In order to satisfy both the light weight and the manufacturing cost reduction based on these demands, research and development have been carried out to manufacture the iron rope material through the aluminum casting first through mold casting and die casting, There is a problem in that when the aluminum shaft is solidified, due to the difference in the thermal expansion coefficient between the aluminum shaft and the iron-based lobe due to lack of toughness that can withstand the cam shaft device due to the defect, There is a limit to the application of the thread.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a cam shaft device, in which an aluminum alloy material is cast by an extrusion process, The lob is made by casting, forging, and powder sintering, which is a conventional iron material manufacturing method, or the aluminum alloy is manufactured by the over-processing Al-Si alloy and aluminum The composite material is manufactured by extrusion. The shaft and the lobe can be joined to each other by using the female / male or male / female concavity and convexity, and the shaft is extruded in a polygonal shape. It is possible to manufacture with a polygonal shape. In the camshaft device, A camshaft device capable of manufacturing an ultra-lightweight shaft economically while ensuring excellent durability and capable of press-fitting and joining without a difference in shrinkage ratio occurring in conventional aluminum casting, And a manufacturing method thereof. However, these problems are exemplary and do not limit the scope of the present invention.

According to an aspect of the present invention, there is provided a camshaft apparatus including: a shaft; A lobe mounted on the shaft; And a locking member provided between the shaft and the lobe so that the lobe can be fixed to the shaft.

According to an aspect of the present invention, the engaging member may be a boss provided on the inner surface of the lobe in the longitudinal direction of the shaft so as to engage with the engaging groove formed in the shaft.

Further, according to an aspect of the present invention, the engagement protrusion includes a neck portion protruding from an inner diameter surface of the lobe to a first length, and having a first width partially; And a head part installed at the tip of the neck part and having a second width at least partially equal to the first width.

According to an aspect of the present invention, the engaging member may be a bossing protrusion provided on an outer diameter surface of the shaft in a longitudinal direction of the shaft so as to engage with a engaging groove formed on an inner diameter surface of the lobe.

Further, according to an aspect of the present invention, the engagement protrusion includes: a neck portion protruding from the outer diameter surface of the shaft to a third length and partially having a third width; And a head part installed at a tip of the neck part and partially having a fourth width of the third width or more.

According to an aspect of the present invention, a plurality of the engaging members may be equally disposed in consideration of the number of cylinders of the engine and the number of valves installed on the basis of the center of rotation of the shaft.

According to an aspect of the present invention, the engaging member may be a polygonal member provided on the outer surface of the shaft in the longitudinal direction of the shaft so as to engage with the polygonal surface formed on the inner surface of the lobe.

According to an aspect of the present invention, the shaft is an extruded product containing an aluminum component and extrusion-molded, and the lobe includes an aluminum component and is at least one of extrusion, forging, casting, powder sintering, Or may be a molded product which is molded by selecting one or more.

Further, according to the idea of the present invention, the lobe may be a molded product containing an iron-based component such as cast iron or cast steel and being molded by selecting at least one of casting, drawing, forging, powder sintering and combinations thereof.

According to an aspect of the present invention, the shaft may be formed with a hollow in its longitudinal direction.

According to another aspect of the present invention, there is provided a shaft according to the present invention, wherein the shaft has an engaging member for engaging with the lobe on one side so as to fix the lobe, and includes an aluminum component and may be extrusion-molded.

According to another aspect of the present invention, there is provided a method of manufacturing a camshaft device, the method including: a shaft forming step of aluminum extrusion-molding a shaft corresponding to the engaging member so that the lobe can be fixed; A lobe forming step of forming the lobe so that the engaging member that can be assembled with the shaft is formed; Assembling the lobe to the shaft; And a joining step of joining the lobe assembled to the shaft to the shaft.

Further, according to the idea of the present invention, the lobe forming step may be a step of forming the lobe by aluminum extrusion molding.

According to some embodiments of the present invention as described above, it is possible to mass produce, improve productivity and economical efficiency, lighten product, produce high-quality products without internal defects, and assemble robustly So that the durability can be greatly improved. Of course, the scope of the present invention is not limited by these effects.

1 is an exploded perspective view of a part of a camshaft apparatus according to some embodiments of the present invention.
2 is a perspective view of the component assembly of Fig.
3 is a cross-sectional view of the shaft of Fig.
Fig. 4 is a sectional view showing the lobe of Fig. 1;
5 is a cross-sectional view illustrating a shaft of a camshaft apparatus according to some other embodiments of the present invention.
Figure 6 is a cross-sectional view of a lobe assembled to the shaft of Figure 5;
7 is a cross-sectional view illustrating a shaft of a camshaft device in accordance with some further embodiments of the present invention.
8 is a cross-sectional view showing a lobe assembled to the shaft of Fig.
9 is a flowchart showing a method of manufacturing a camshaft device according to some embodiments of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The embodiments of the present invention are described in order to more fully explain the present invention to those skilled in the art, and the following embodiments may be modified into various other forms, The present invention is not limited to the embodiment. Rather, these embodiments are provided so that this disclosure will be more thorough and complete, and will fully convey the concept of the invention to those skilled in the art. In the drawings, the thickness and size of each layer are exaggerated for convenience and clarity of explanation.

It is to be understood that throughout the specification, when an element such as a film, region or substrate is referred to as being "on", "connected to", "laminated" or "coupled to" another element, It will be appreciated that elements may be directly "on", "connected", "laminated" or "coupled" to another element, or there may be other elements intervening therebetween. On the other hand, when one element is referred to as being "directly on", "directly connected", or "directly coupled" to another element, it is interpreted that there are no other components intervening therebetween do. Like numbers refer to like elements. As used herein, the term "and / or" includes any and all combinations of one or more of the listed items.

Although the terms first, second, etc. are used herein to describe various elements, components, regions, layers and / or portions, these members, components, regions, layers and / It is obvious that no. These terms are only used to distinguish one member, component, region, layer or section from another region, layer or section. Thus, a first member, component, region, layer or section described below may refer to a second member, component, region, layer or section without departing from the teachings of the present invention.

Also, relative terms such as "top" or "above" and "under" or "below" can be used herein to describe the relationship of certain elements to other elements as illustrated in the Figures. Relative terms are intended to include different orientations of the device in addition to those depicted in the Figures. For example, in the figures the elements are turned over so that the elements depicted as being on the top surface of the other elements are oriented on the bottom surface of the other elements. Thus, the example "top" may include both "under" and "top" directions depending on the particular orientation of the figure. If the elements are oriented in different directions (rotated 90 degrees with respect to the other direction), the relative descriptions used herein can be interpreted accordingly.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms "a," "an," and "the" include singular forms unless the context clearly dictates otherwise. Also, " comprise "and / or" comprising "when used herein should be interpreted as specifying the presence of stated shapes, numbers, steps, operations, elements, elements, and / And does not preclude the presence or addition of one or more other features, integers, operations, elements, elements, and / or groups.

Hereinafter, embodiments of the present invention will be described with reference to the drawings schematically showing ideal embodiments of the present invention. In the drawings, for example, variations in the shape shown may be expected, depending on manufacturing techniques and / or tolerances. Accordingly, the embodiments of the present invention should not be construed as limited to the particular shapes of the regions shown herein, but should include, for example, changes in shape resulting from manufacturing.

In embodiments of the present invention, the camshaft device can be generally referred to as including a shaft, a lobe, and an engagement member. It should be understood, however, that the scope of the present invention is not limited only to the above terms in that in such a camshaft device the shaft may be referred to as a camshaft, and the lobe may also be referred to as a cam lobe or simply as a cam.

Fig. 1 is an exploded perspective view of a part of a camshaft apparatus 100 according to some embodiments of the present invention, Fig. 2 is a perspective view of the assembly of Fig. 1, Fig. 3 is a cross- And Fig. 4 is a sectional view showing the lobe 20 of Fig.

1 to 4, a camshaft apparatus 100 according to some embodiments of the present invention includes a shaft 10, a lobe 20, and a stabbing member 30 .

Here, the shaft 10 may be, for example, a kind of rotary shaft provided with the lobe 20 for opening and closing an intake valve and an exhaust valve of the engine. Of course, the shaft 10 is not necessarily installed in the engine, and rotary shafts equipped with lobes widely used in various types of devices and equipments can be applied.

Also, as shown in FIGS. 1 to 3, for example, the shaft 10 may be formed into a pipe shape having a hollow 10b formed therein in the longitudinal direction, in order to reduce the weight and increase the strength of the product. When the shaft 10 is formed into a pipe shape, the shearing force of one side surface of the shaft 10 can not pass through the center of the shortest distance by the hollow 10b, The weight of the product can be reduced, and at the same time, the strength can be further increased. The diameter of the hollow 10b can be optimally designed according to the material characteristics of the shaft 10, the use environment, the processing characteristics, the specification characteristics, and the like. Also, the hollow 10b is not necessarily formed. For example, as shown in FIG. 5, the hollow 10b may be omitted.

For example, the shaft 10 may be an aluminum material of 2,000 series, 4000 series, 5,000 series, 6000 series, 7000 series, etc. In addition, a magnesium alloy, a titanium alloy, or the like may be applied .

Further, the shaft 10 can be extrusion-molded using the above-described materials so that the structure is dense, the weight of the product is increased, and the productivity is increased.

The lobe 20 is a kind of mechanical element installed on the shaft 10 and capable of opening and closing various valves by using the bending of the surface of the lobe 20, Such as press fitting, brazing, MIG and TIG bonding, friction bonding, screw rotation, and the like.

The lobes 21, 22, 23, and 24 shown in FIGS. 1 and 2 are arranged in the order of 4 One camshaft device applied to a double overhead camshaft engine is illustrated in the engine of the cylinder.

A journal portion 11 (corresponding to a bearing (not shown)) for rotatably supporting the shaft 10 is provided between the lobes 21, 22, 23 and 24 provided on the shaft 10 12, 13, and 14, respectively. For example, the journal portions 11, 12, 13, and 14 may cut the shaft 10 and mold it.

Here, the lobe 20 may be made of an aluminum alloy material such as an Al-Si alloy and an Al composite material. However, such the lobe 20, but not limited to, Ductile cast iron, gray cast iron, chilled cast iron, such as iron based or, Carbon steel, Alloy steel, the main spectrometer or, made of Nitriding steel such as Ti ₆ Al consisting of ₄ V and Titanium composite material may be applied.

Further, the lobes 20 may be extruded using the above-mentioned materials so that the structure is dense, the weight of the products is increased, and the productivity is increased. However, the lobe 20 is not limited to this, and may be manufactured by a method such as casting, powder sintering (in-situ synthesis), or the like.

The shaft 10 and the lobe 20 can further improve strength and durability through other surface coating or heat treatment.

The locking member 30 may be installed between the shaft 10 and the lobe 20 so that the lobe 20 can be fixed to the shaft 10, for example.

More specifically, as shown in Figs. 1 to 4, the engaging member 30 is fixed to the inner surface of the lobe 20 so as to be engaged with the engaging groove 10a formed in the shaft 10 20a of the shaft 10 in the longitudinal direction of the shaft 10.

4, the engaging projection 31 protrudes from the inner surface 20a of the lobe 20 to the first length L1 and partially has the first width W1 And may include a neck portion 31-1 and a head portion 31-2 provided at the tip of the neck portion 31-1 and having a second width W2 at least partially equal to the first width W1 .

Here, the head 31-2 may be a round head, and various other types of head such as a triangular head, a square head, a polygonal head, and an elliptical head may be formed.

In addition, the neck 31-1 has a lower width, but has a narrower width as it goes up, partially having the first width W1.

Therefore, when the engaging protrusion 31 is inserted into the engaging groove 10a by using the neck 31-1 and the head 31-2, the second width of the head 31-2 The wedge protrusion 31 can not be easily detached in the direction of the outer surface of the shaft 10 because the wedge W2 is greater than the first width W1 and the bite protrusion 31 is inserted into the plurality of bite grooves 10a, A more rigid fixation of the < / RTI >

A plurality of the engaging projections 31 may be equally spaced in consideration of the number of cylinders of the engine and the number of valves installed on the basis of the center of rotation of the shaft 10.

More specifically, in the case where the engine is a three-cylinder type, six or nine engagement protrusions 31 can be equally arranged so that a phase difference of 120 degrees can be realized. In the case where the engine is a four-cylinder type, Four, eight, or twelve of the engagement protrusions 31 may be equally spaced.

In the case where the engine is a five cylinder type, five or ten engagement protrusions 31 may be equally disposed so as to realize a phase difference of 72 degrees, and when the engine is six cylinders, Six, or nine of the engagement protrusions 31 may be equally spaced, and four, eight, or twelve of the engagement protrusions 31 may be equiangularly arranged so that a phase difference of 90 degrees can be achieved when the engine is an eight cylinder. In addition, various angles can be implemented according to the phase difference of the cylinder.

5 is a sectional view showing a shaft 40 of a camshaft apparatus 200 according to some other embodiments of the present invention and FIG. 6 is a cross-sectional view showing a lobe 50 assembled to the shaft 40 of FIG. 5 .

5 and 6, a camshaft apparatus 200 according to some other embodiments of the present invention includes a shaft 40, a lobe 50 mounted on the shaft 40, And a locking member 60 installed between the shaft 40 and the lobe 50 so that the locking member 50 can be fixed to the shaft 40.

Here, the engaging member 60 is provided on the outer diameter surface 40a of the shaft 40 so as to engage with the engaging groove 50b formed on the inner diameter surface 50a of the lobe 50, And may be a bite projection 61 provided in the longitudinal direction.

5, the engaging protrusion 61 protrudes from the outer diameter surface 40a of the shaft 40 to the third length L3 and has a partly third width W3 And may include a neck portion 61-1 and a head portion 61-2 provided at the tip of the neck portion 61-1 and partially having a fourth width W4 of the third width W3 or more .

Here, the head part 61-2 may be a round head part, and various types of head parts such as a triangular head part, a square head part, a polygonal head part, and an elliptical head part may be formed.

In addition, the neck portion 61-1 has a wide width at its lower portion, but narrows its width as it goes up, partially having the third width W3.

Therefore, when the engaging protrusion 61 is inserted into the engaging groove 40a by using the neck portion 61-1 and the head portion 61-2, the fourth width of the head portion 61-2 The wedge protrusion 61 can not be easily released in the outer diameter direction of the shaft 40 because the wedge groove W4 is greater than the third width W3. A more rigid fixation of the < / RTI >

A plurality of the engaging projections 61 may be equally spaced in consideration of the number of cylinders of the engine and the number of valves installed on the basis of the center of rotation of the shaft 40.

7 is a cross-sectional view showing a shaft 70 of a camshaft apparatus 300 according to some further embodiments of the present invention and Fig. 8 is a cross-sectional view showing a lobe 80 assembled to the shaft 70 of Fig. 7 to be.

7 and 8, a camshaft apparatus 300 according to still another embodiment of the present invention includes a shaft 70, a lobe 80 installed on the shaft 70, And a locking member 90 provided between the shaft 70 and the lobe 80 so that the lobe 80 can be fixed to the shaft 70.

7, the engaging member 90 is formed so as to be engaged with the outer surface 80b of the shaft 70 so as to engage with the polygonal surface 80b formed on the inner surface 80a of the lobe 80 in Fig. 8, (91) provided on the shaft (70a) in the longitudinal direction of the shaft.

A plurality of the polygonal surfaces of the engaging member 90 may be conformally formed in consideration of the number of cylinders of the engine and the number of valves installed on the basis of the center of rotation of the shaft 70.

More specifically, in the case where the engine is a three-cylinder type, the engaging member 90 may be a hexagonal bevel or a hexagonal bevel so that a phase difference of 120 degrees can be realized, and when the engine is a four- The engaging member 90 may be a quadrangular, octagonal, or hexagonal prism.

In addition, in the case where the engine is a five-cylinder engine, the engaging member 90 may be a pentagonal bevel or a hexagonal bevel, so that a phase difference of 72 degrees can be realized. The engagement member 90 may be a hexagonal bevel or a hexagonal bevel. When the engine is an eight-cylinder type, the engagement member 90 may be a quadrangular, octagonal, or octagonal 12 It may be an octahedron. In addition, various types of polygonal shapes can be realized depending on the phase difference of the cylinder.

9 is a flowchart showing a method of manufacturing the camshaft apparatus 100 according to some embodiments of the present invention.

1, 2 and 9, a method of manufacturing a camshaft apparatus 100 according to some embodiments of the present invention includes the steps of: A lobe forming step S2 for forming the lobe 20 so as to form the engaging member 30 which can be assembled with the shaft 10; a shaft forming step S1 for aluminum extrusion- (S3) for assembling the lobe (20) to the shaft (10), a joining step S4 for joining the lobe (20) assembled to the shaft (10) to the shaft And a journal forming step S5 of forming the journal portion by processing the shaft 10.

The lobe forming step S2 may be a step of forming the lobe 20 by aluminum extrusion molding. In addition, the lobe 20 may be forged by a forging machine.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10, 40, 70: Shaft
20, 21, 22, 23, 24, 50, 80: Robes
30, 60, 90:
100, 200, 300: Camshaft device
11, 12, 13, 14: journal portion
10a: Biting Home
10b: hollow
20a: inner surface
31: Bite projection
L1: first length
W1: First width
31-1: neck
W2: second width
31-2: Head
40a: outer diameter face
50a: inner surface
50b: Bottom groove
61: Bite projection
L3: Third length
61-1: neck
W3: third width
W4: fourth width
61-2: Head
70a: outer diameter surface
80a: inner surface
80b:
91: polyhedron

Claims (16)

A shaft;
A lobe mounted on the shaft; And
A locking member provided between the shaft and the lobe so that the lobe can be fixed to the shaft;
And the camshaft device. The method according to claim 1,
Wherein:
And the engaging protrusion is provided on the inner diameter surface of the lobe so as to engage with the engaging groove formed in the shaft in the longitudinal direction of the shaft. 3. The method of claim 2,
The bite-
A neck projecting from the inner surface of the lobe to a first length and having a partially first width; And
A head portion provided at a tip of the neck portion and partially having a second width greater than or equal to the first width;
And the camshaft device. The method of claim 3,
Wherein the head portion is a round head portion. The method according to claim 1,
Wherein:
Wherein the engaging protrusion is a boss provided on an outer diameter surface of the shaft so as to engage with the engaging groove formed on the inner surface of the lobe in the longitudinal direction of the shaft. 6. The method of claim 5,
The bite-
A neck portion protruding from the outer diameter surface of the shaft to a third length and partially having a third width; And
A head portion provided at a tip of the neck portion and partially having a fourth width equal to or greater than the third width;
And the camshaft device. The method according to claim 6,
Wherein the head portion is a round head portion. The method according to claim 1,
Wherein a plurality of the engaging members are equally arranged in consideration of the number of cylinders of the engine and the number of valves installed on the basis of the center of rotation of the shaft. The method according to claim 1,
Wherein:
And a polygonal member provided in a longitudinal direction of the shaft on an outer surface of the shaft so as to be engaged with a polygonal surface formed on an inner surface of the lobe. 10. The method according to any one of claims 1 to 9,
Wherein the shaft is an extrudate which comprises an aluminum component and is extrusion-molded. 11. The method of claim 10,
Wherein the lobe is a molded product comprising an aluminum component and at least one selected from at least one of extrusion, forging, casting, powder sintering, and a combination thereof. 11. The method of claim 10,
Wherein the lobe is a molded product that contains an iron-based component such as cast iron or cast steel and is molded by selecting at least one of casting, drawing, forging, powder sintering, and combinations thereof. The method according to claim 1,
Wherein the shaft is formed with a hollow in the longitudinal direction therein. A stitching member is provided at one side so as to be engaged with the lobe so that the lobe can be fixed,
Comprising an aluminum component,
Wherein the shaft is extruded. A shaft forming step of aluminum extrusion-molding the shaft corresponding to the engaging member so that the lobe can be fixed;
A lobe forming step of forming the lobe so that the engaging member that can be assembled with the shaft is formed;
Assembling the lobe to the shaft; And
A joining step of joining the lobe assembled to the shaft to the shaft;
Wherein the camshaft comprises a camshaft. 16. The method of claim 15,
Wherein the lobe shaping step is a step of shaping the lobe by aluminum extrusion molding.

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