WO2013165068A1

WO2013165068A1 - Wheel for wide commercial vehicle and method for manufacturing same

Info

Publication number: WO2013165068A1
Application number: PCT/KR2012/011274
Authority: WO
Inventors: 하태수
Original assignee: (주)레오포즈
Priority date: 2012-05-03
Filing date: 2012-12-21
Publication date: 2013-11-07
Also published as: KR101395022B1; KR20130123651A

Abstract

The present invention relates to a wheel for a wide commercial vehicle and a method for manufacturing same, more specifically to a new single wheel-type wheel for a wide commercial vehicle having a single rim part and a single hub formed as an integrated body in the center of the internal diameter of the rim part, and to a method for manufacturing same. To that end, after pre-forming in which a semi-solid is forged using an aluminum-wrought alloy material, an improved new single wheel-type structure, having a single rim part and a single hub part formed as a single body in the center of the internal diameter of the single rim part, is formed by means of processes such as a flow-forming process, and thus the present invention provides a wheel for a wide commercial vehicle and a method for manufacturing same allowing not only a reduction in the weight of the product, but also allows reductions in material usage and production costs, decreased forging cycle time, and increases in the tensile and fatigue strengths due to a change in materials used.

Description

Wide commercial wheels and manufacturing method thereof

The present invention relates to a wheel for a wide commercial vehicle and a manufacturing method thereof, and more particularly, a wheel for a wide wheel type wide commercial vehicle having a new structure including one hub portion and one rim portion extending inward and outward from an outer circumferential end of the hub portion. It relates to a manufacturing method thereof.

Aluminum wheels for commercial vehicles consist of a rim part for tire mounting, and a hub part integrally formed on one side of the rim part for coupling with a hub connected to the axle, and includes low pressure casting, differential pressure casting, vacuum suction casting, and high pressure casting (Die Casting). ), Squeeze casting method is applied, and most aluminum disk wheel companies adopt low pressure casting method to secure the soundness of castings.

However, the low pressure casting method is suitable for mass production of aluminum wheels and the manufacture of small parts, and has excellent mass production, but is weak in securing reliability due to the limitation of strength and toughness. There are disadvantages.

As a result, some companies use a melt casting method or a vacuum pressure casting method to realize a 15% lighter weight than a low pressure casting method, but the quality thereof is lower than that of the forging method.

Therefore, aluminum disc wheels are manufactured using the hot forging method in accordance with the trend that the aluminum wheel manufacturing method has been converted to a forging method having a high unit price but relatively high quality.

The hot forging is a plastic working method for producing a roughly shaped material by pressing a billet with a large press. The metal tissue is stretched by pressing, and the small micropores in the inside are pressed to minimize defects, thereby reducing strength and toughness. There is an advantage that can be increased.

The hot forging method has a disadvantage in that the manufacturing cost increases and the size and initial investment of the equipment must be increased as the product is formed through various step-by-step repetitive processes because it cannot manufacture a complicated shape at once, and also the size and use of equipment It is difficult to recycle the billet, and the material cost is very high, which causes problems in mass production and cost competitiveness of automobile parts.

The method developed to make up for the shortcomings of the hot forging is a rotating forging method that is divided into two step processes. The pre-form step, which is the first step of the forging method, utilizes a relatively small pressing force. As a stress-intensive rotary forging step, a basic shape is formed, and then, as a second step, a spinning process of flow forming a detail part is performed.

However, this rotation forging and spinning method also has a limit in the reduction of the material cost, which accounts for more than 70% of the cost of the parts because it is impossible to recycle the material.

In view of this, a reaction solid forging method has been proposed that makes good use of the advantages of casting and forging. After the material is melted and put into the mold, solidification and pressurization are carried out by an appropriate mechanism, thereby forming a complex shape in a solid liquid coexistence state. It is a method of forming and producing products at once.

The reaction solidification forging method has high material adhesion rate due to pressurization, high solidification rate, fast production speed, and can fundamentally solve shrinkage defects occurring during material solidification, allowing mass production of large products, and also directly applying high pressure directly to the material. By adding, it is possible to control the spheroidization of the tissue, and there is an advantage that the product weight can be realized by increasing the strength.

However, as shown in the accompanying FIG. 4, the wheels 30 for the rear wheels of the cargo and the trailer, which are manufactured using the conventional reaction high forging method, are mostly divided into inner and

outer wheels

32 and 34, respectively. As the wheel of is applied, the number of manufacturing and assembly, and the number of parts for assembly, etc. were increased.

That is, the conventional rear wheel wheels are arranged in close contact with the inner wheel and the outer wheel side by side, the hub portion formed on the outside of the inner wheel and the hub portion formed inside the outer wheel are in close contact with each other, connected to the drive shaft It is structured to be assembled with the wheel hub to transmit power.

As two double-wheeled wheels, such as an inner wheel and an outer wheel, are applied to support a single tire, this results in an increase in man-hours and manufacturing costs for wheel manufacturing, and increases weight, causing weight to counterweight. There was a disadvantage in that the number of assembly and assembly parts and the like increases.

The present invention has been made in view of the above, and the center of the inner diameter of the single rim portion and the single rim portion through a process of preforming the reaction and forging using the whole body material aluminum alloy material, and then flow forming (Flow Forming), etc. It is improved by a new single-wheel type structure composed of a single hub part integrally formed in the body, and it is a wide commercial vehicle that can reduce product weight, reduce material usage and cost, reduce forging cycle time, and increase tensile and fatigue strength due to material change. Its purpose is to provide a wheel and a manufacturing method thereof.

According to an aspect of the present invention, there is provided a wheel for a wide commercial vehicle, comprising: a single hub unit integrally assembled with a wheel hub connected to the drive shaft so as to transmit power; A single rim portion consisting of an inner rim portion and an outer rim portion extended to both sides by flow molding about an outer circumferential end portion of the single hub portion to support a rear wheel of a commercial vehicle; It provides a wide wheel for commercial vehicles, characterized in that consisting of.

The present invention for achieving the above object is a method for manufacturing a wheel for a wide commercial vehicle, by injecting a molten aluminum dissolved in a metal into a mold, provided with a preformed wheel formed integrally with the inner rim and the outer rim around a single hub portion; A reaction solidification forging step; Primary flow molding process in which the outer surface of the inner rim of the fixed rim of the fixed preform wheel is pressed to the first fluid forming chuck by the first flow forming roller and pressed down to the designed thickness and at the same time extends to the design width in the inward direction. And a second flow molding process in which the outer surface of the outer rim of the single rim of the preformed wheel is pressed to the second fluid forming chuck by the second fluid forming roller and pressed down to the designed thickness, while at the same time extending to the design width in the outward direction. This bi-directional flow forming step is made at the same time; It provides a wide wheel manufacturing method for a commercial vehicle comprising a.

In particular, when the first flow-forming chuck and the second flow-forming chuck face each other, they are horizontally arranged to insert and fix the first flow-forming chuck of the flow-forming part in one opening of the pre-formed wheel, and at the other side of the pre-formed wheel. The second flow-forming chuck on the other side of the flow-forming part is inserted into and fixed, so that the bi-directional flow molding can be performed while the preforming wheel is arranged horizontally.

The method may further include a T6 heat treatment or a solution heat treatment step performed to process the center hole for the preformed wheel after the reaction forging step, and an aging heat treatment or T6 heat treatment step performed after the bidirectional flow forming step. It is done.

Preferably, the aluminum material is characterized in that it is adopted as a whole material 6000 series material or casting A300 series material in order to increase the tensile strength.

Through the above problem solving means, the present invention provides the following effects.

According to the present invention, after the preformed wheels are prepared by reacting and forging by using the whole body material 6000 series material or casting A300 series material, preferably AA6061 aluminum alloy material to increase the tensile strength, and then preformed By manufacturing the wheels for wide-area commercial vehicles by bidirectional flow forming the wheels, a single rim portion is formed of a single hub portion, an inner rim portion and an outer rim portion extending from both sides about the outer circumferential end portion of the single hub portion to support the rear wheel of the commercial vehicle. It is possible to provide a wide wheel for commercial vehicles.

In particular, in contrast to the conventional two-wheel type wheels, such as the inner wheel and the outer wheel to support a single tire, the wheel for the wide-width use of the present invention is a single wheel in which the inner rim and the outer rim is connected to the inside and the outside around a single hub portion By manufacturing the type structure, it is possible to reduce product weight, reduce material usage and cost, reduce forging cycle time, and increase tensile and fatigue strength due to material change.

1a to 1d is a schematic diagram showing the reaction high forging process of the wheel for a wide-range commercial vehicle according to the present invention and a manufacturing method thereof;

2 is a schematic view showing a center hole processing process as a wheel for a commercial vehicle and a manufacturing method thereof according to the present invention;

3a to 3d is a schematic view showing a bidirectional flow forming process as a wheel for a wide-range commercial vehicle and a method of manufacturing the same according to the present invention,

Figure 4 is a cross-sectional view showing the final product specifications of the wheel for a wide commercial vehicle according to the present invention,

5 is a schematic view illustrating a conventional wheel manufacturing method.

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

1A to 1D are schematic cross-sectional views illustrating a reaction solidification forging process of a method for manufacturing a wide wheel for commercial vehicles according to the present invention.

The reaction solid forging device for manufacturing a wheel for a wide-use car of the present invention is a preforming part 100 for preforming the shape of an aluminum wheel, and an upper mold 104 and an ejection punch mounted on an upper plate 102 on an upper side thereof. 106 is disposed.

More specifically, the hydraulic cylinder (not shown) is coupled to the upper surface of the upper plate 102, the upper mold 104 for the reaction high forging of the aluminum wheel integrally to the bottom edge of the upper plate 102. It is assembled, and the blowout punch 106 is mounted to the center of the upper plate 102 so that the upper punch cylinder 107 can be moved up and down.

The lower mold 108 having a molten metal filling space is assembled on the lower plate 112 at the lower side of the upper mold 104, and the lower working shaft 109 is formed at the center of the lower mold 108. The lower ejection cylinder 111, which is positioned to be capable of raising and lowering and is a lowering driving means of the lower operation shaft 109, is disposed at the bottom of the lower plate 112.

In addition, a rail-shaped guide 113 is mounted on an outer circumferential lower plate 112 of the lower mold 108, and a side holder 114 is disposed on the rail-shaped guide 113 so as to be able to move forward and backward.

At this time, the side mold 110 is integrally assembled on the front surface of the side holder 114, and the hydraulic cylinder 115 that is the forward and backward driving means is disposed on the rear surface.

Looking at the reaction forging process proceeded by the reaction forging forging preform 100 configured as follows.

First, the side holder 114 and the side mold 110 are advanced along the rail guide 113 by the driving of the hydraulic cylinder 115 to be in close contact with the side of the lower mold 108 to form a preform of an aluminum wheel. A cavity 116 is formed for shaping the mold.

Subsequently, in order to increase the tensile strength in the cavity 116, a molten metal melted into a 6000 series material or a cast A300 material is injected, and a molten melted AA6061 material is injected to increase the tensile strength.

Next, the upper mold 104 is lowered and the reaction solid forging process of pressurizing the molten metal in the cavity 116 is performed, thereby completing the preform of the aluminum wheel.

Subsequently, as shown in FIG. 1C, the upper mold 104 is lifted to its original position and the lower working shaft 109 is in the lower mold 108 by driving the lower eject cylinder 111. By pushing up, the aluminum wheel 10, which is a preform, is lifted together with the upper mold 104.

Subsequently, in the state where the upper mold 104 is stopped as shown in FIG. 1D, the ejection plate 118 is moved and disposed by a transport robot (not shown), and at the same time, the upper ejection cylinder ( The ejection punch 106 which is lowered by the driving of the 107 pushes down the aluminum wheel 10, which is a preform, so that the aluminum wheel 10 is seated on the ejection plate 118.

At this time, the preformed aluminum wheel 10 does not form a complete wheel shape out of the designed dimensions and shapes, but each of the inner and outer sides of the single hub portion 12 and the outer peripheral end of the single hub portion 12, respectively. It comprises a single rim portion 18 consisting of an inner rim portion 14 and an outer rim portion 16 extending in the direction.

Next, as shown in the accompanying FIG. 2, the aluminum wheel 10 preformed by reaction forging and seated on the take-out plate 118 is transferred to the center hole processing line, which is the next process, and then the center hole processing line. The center hole 28 of a predetermined size is penetrated by using a predetermined machining means such as a drill at the center position of the single hub portion 12 of the aluminum wheel 10 mounted on the work target.

Here, the bi-directional flow forming process of the wheel manufacturing method for a wide commercial vehicle according to the present invention will be described.

3A to 3C are schematic views illustrating a bidirectional flow forming process of a wheel manufacturing method for a wide range commercial vehicle according to the present invention.

The wheel for a wide-scale commercial vehicle according to the present invention has a single hub portion 12 that is integrally assembled with a wheel hub (not shown) connected to the drive shaft so as to transmit power, and inward and outward from an outer peripheral end of the single hub portion 12. It is made of a single-wheel type structure consisting of a single rim portion 18 extended to the.

More specifically, as shown in the accompanying FIG. 4, the wheel of the present invention extends in and outwardly about a single hub portion 12 and an outer circumferential end portion of the single hub portion 12 by bidirectional flow molding. The inner rim portion 14 and the outer rim portion 16 are composed of a single rim portion 18 to support the rear wheel of the commercial vehicle, the single hub portion 12 and the single rim portion 18 to form a "I" cross-sectional structure with each other do.

In the bidirectional flow molding for manufacturing the wheel for the wide-scale commercial vehicle of the present invention manufactured with such a single-wheel type structure, the first flow molding process and the second flow molding process are simultaneously performed.

As the configuration for the bi-directional flow molding, the first flow forming chuck 22 and the second flow forming chuck 26 are arranged horizontally facing each other, the outer diameter and the second flow forming of the first flow forming chuck 22 The first flow-forming roller 20 and the second flow-forming roller 24 are disposed in the outer diameter portion of the chuck 26 so as to be able to be moved forward / backward / leftward / rightward by predetermined hydraulic driving means.

In this case, for the first flow molding process and the second flow molding process, the preformed wheel is clamped to the first flow forming chuck 22 and the second flow forming chuck 26 by reaction forging.

That is, the inner rim portion 14 and the outer rim portion 16 of the single rim portion 18 are formed integrally around the single hub portion 12 of the aluminum wheel 10 which is the preformed body, and the single rim portion 18 is formed. The first flow forming chuck 22 is inserted into and fixed in the inner rim portion 14 of the second flow molding chuck 24 into the outer rim portion 16 of the single rim portion 18 (see FIG. 3A).

Subsequently, the outer surface of the inner rim portion 14 of the single rim portion 18 of the aluminum wheel, which is a preform, is pressed to the outer diameter of the first flow forming chuck 22 by the first flow forming roller 20 and pressed to the designed thickness. At the same time, the primary flow molding process is performed to increase the design width in the inward direction, and at the same time, the outer surface of the outer rim portion 16 of the single rim portion 18 is formed by the second flow forming roller 24 for the second flow molding. A second flow forming process is performed to press the outer diameter of the chuck 26 and to reduce the thickness to the designed thickness while pressing the outer diameter to the design width in the outward direction (see FIGS. 3B and 3C).

On the other hand, the conventional vertical flow molding method has a disadvantage in that the machine shakes and the amount of material flow is limited when high pressure is applied, so in the case of a small size wheel for a passenger car, the amount of material flow is small and the thickness is thin. In the case of manufacturing a wide wheel for a commercial vehicle according to the present invention, since the thickness of the wheel is thick and a large amount of material must flow, it must be pressurized with a force of 25 tons or more.

To this end, in the manufacturing method of the wide wheel of the present invention, the first flow forming chuck 22 and the second flow forming chuck 26 are arranged to face each other in the horizontal direction, and thus the first and second flow forming rollers ( Horizontal type flow molding according to 20) is performed, and even if a force of 25 tons or more is pressed by the first and second flow-forming rollers 20, the wheel product is not shaken and the degree of dimension is increased.

In this way, the wheel is designed pre-formed by the primary and secondary flow molding process, that is, a single hub portion 12, and a single rim portion 18 extending in and outward from the outer peripheral end of the single hub portion 12 Completed manufacturing with a single-wheel type structure consisting of (see Figure 4).

On the other hand, the T6 heat treatment (solvent-> water bath quenching-> aging) or solution heat treatment step performed to process the center hole on the aluminum wheel which is a preform after the reaction high forging step is carried out, in particular after the bidirectional flow forming step The aging heat treatment step or T6 heat treatment may be performed to maintain the tensile strength, yield strength, elongation, and the like.

The T6 heat treatment step is performed for a critical time of 2 to 5 hours at a critical temperature of 160 ° C to 195 ° C. If the temperature is out of the critical temperature and the critical time, precipitation of the aluminum alloy structure does not occur and the desired hardness cannot be obtained.

Therefore, the T6 heat treatment step is preferably performed for a critical time 2-5 hours at a critical temperature of 160 ℃ ~ 195 ℃.

In this case, even when only the solution heat treatment step is performed, it is preferable to perform the solution treatment for 3 to 7 hours at 500 ° C. to 550 ° C. so as to support the precipitation of the aluminum alloy structure and obtain a desired hardness.

In addition, the wheel 10 for the wide commercial vehicle finally formed by the two-way flow molding is transferred to the hub hole processing portion to further process the actual hub hole in the center of the single hub portion, the hub hole processing is completed in the lathe processing unit After the CNC machining of the inner and outer surfaces of the aluminum wheel 10 is performed, the step of machining bolt holes and vent holes in a single hub portion is further progressed to complete the final aluminum wide commercial vehicle wheel products.

Claims

In the wheel for a wide commercial vehicle,

A single hub portion 12 integrally assembled with the wheel hub connected to the drive shaft so as to transmit power;

A single rim portion 18 consisting of an inner rim portion 14 and an outer rim portion 16 extending from both sides by flow molding about an outer circumferential end portion of the single hub portion 12 to support a rear wheel of a commercial vehicle;

Wide commercial vehicle wheel, characterized in that consisting of.
In the wheel manufacturing method for a wide commercial vehicle,

A molten metal forging step of injecting a molten aluminum material, the preforming wheel having an inner rim portion 14 and an outer rim portion 16 integrally formed around a single hub portion 12;

The outer surface of the inner rim portion 14 of the single rim portion 18 of the fixed preforming wheel is pressed by the first flow forming roller 20 to the first flow forming chuck 22 and reduced to the designed thickness while being pressed inwardly. The first flow molding process to extend the design width to the design width, and the outer surface of the outer rim portion 16 of the single rim portion 18 of the preforming wheel, the second flow forming chuck 26 by the second flow forming roller 24 A bidirectional flow forming step in which a secondary flow forming process is simultaneously pressed to reduce the thickness to the designed thickness while being pressed to the outside and to the design width in the outward direction;

Wheel manufacturing method for a wide range commercial vehicle comprising a.
The method according to claim 2,

The first flow forming chuck 22 and the second flow forming chuck 26 are arranged horizontally facing each other to simultaneously insert and fix the first flow forming chuck 22 of the flow forming part in one opening of the preforming wheel. The second fluid forming chuck 24 of the other side of the flow molding part is fixedly inserted into the other opening of the preforming wheel, so that the bidirectional flow molding can be performed while the preforming wheel is arranged horizontally. Wheel manufacturing method.
The method according to claim 2,

After the reaction high forging step, T6 heat treatment or solution heat treatment step performed to process the center hole for the preformed wheel, and aging heat treatment or T6 heat treatment step performed after the bidirectional flow forming step, characterized in that it further comprises Method for manufacturing wheels for wide commercial vehicles.
The method according to claim 2,

The aluminum material is a wheel manufacturing method for a wide-range commercial vehicle, characterized in that it is adopted as a body material 6000 series material or casting A300 series material to increase the tensile strength.
The method according to claim 4,

The T6 heat treatment step is carried out for 2 to 5 hours at 160 ℃ ~ 195 ℃, the solution heat treatment step is a wheel manufacturing method for a wide commercial vehicle, characterized in that for 3 to 7 hours at 500 ℃ ~ 550 ℃.