KR20210062241A - Blank local heating device - Google Patents

Abstract

The purpose of the present invention is to provide an unequal-heating device for unequal-heating different parts of a blank at different temperatures. To achieve the purpose, the unequal-heating device for partially heating a blank at different temperatures comprises an upper heating furnace and a lower heating furnace installed below the upper heating furnace. The upper heating furnace is formed to be movable upward with respect to the lower heating furnace. The upper heating furnace includes: a plurality of upper heat source parts consisting of high- and low-temperature upper heat source parts; and an upper plate consisting of a high-temperature upper plate and a low-temperature upper plate, respectively installed below the high-temperature and low-temperature upper heat source parts. The lower heating furnace includes: a plurality of lower heat source parts consisting of high- and low-temperature lower heat source parts corresponding to the plurality of upper heat source parts, and installed therebelow; and a lower plate consisting of a high-temperature lower plate and a low-temperature lower plate, respectively installed on the high- and low-temperature lower heat source parts. An upper part of the blank is disposed between the high-temperature upper plate and the high-temperature lower plate, and the lower part of the blank is disposed between the low-temperature upper plate and the low-temperature lower plate, so that the upper and lower parts are heated.

Description

Blank differential heating device {BLANK LOCAL HEATING DEVICE}

The present invention relates to a blank differential heating device, and more particularly, to a blank differential heating device capable of securing different strengths for each section within a single blank component.

In general press forming, after cutting the raw material of a cold-rolled or hot-rolled coil, transfer the material, put it into a press mold, press it to complete the molding, and then cut the unnecessary part and form a hole. Complete.

Such conventional press forming is nothing more than realizing the shape of a part by simply processing the strength and physical properties of a steel plate manufactured by a steel company. Therefore, since the property of the raw material becomes the property of the part after processing, press molding becomes difficult as the strength of the raw material increases, making it difficult to realize the precise shape of the product.

Recently known hot stamping technology is performed at high temperatures, unlike conventional press forming in a cold state.

Hot stamping is a method of producing high-strength parts by heating a steel sheet to a high temperature of 900°C or higher, forming it with a press, and rapidly cooling it.

At high temperatures, since the elongation of the material increases significantly, there is no particular restriction on formability, and there is an advantage in that ultra-high strength can be achieved by the heat treatment effect.

In this respect, the hot stamping technology can be seen as a suitable method for forming a vehicle body part for high strength and weight reduction of a vehicle in accordance with a growing interest in environment-friendly and social atmosphere.

However, even in the case of vehicle body parts to which hot stamping technology is applied, a technology capable of securing different strengths for each part according to the purpose of use within one part, in other words, a processing technology capable of securing differential strength is required.

Korean Registered Patent Publication No. 1033361 (Name of the invention: Method for manufacturing hot press molded body with improved productivity)

The present invention has been made to solve the above-described problem, and it is an object of the present invention to provide a differential heating device for differential heating at different temperatures by different parts of a blank.

In order to solve the above problems, the present invention is a differential heating device for partially heating a blank to a different temperature, comprising an upper heating furnace and a lower heating furnace installed under the upper heating furnace, and the upper heating The furnace is formed so as to be movable upward with respect to the lower heating furnace, and the upper heating furnace includes a plurality of upper heat sources including high and low temperatures, and a high temperature upper plate respectively installed below the high and low temperature upper heat sources. And an upper plate made of a low temperature upper plate, wherein the lower heating furnace comprises a plurality of lower heat source parts provided at high and low temperature corresponding to the plurality of upper heat sources and installed at a lower portion, and a lower portion of the high and low temperature And a lower plate comprising a high-temperature lower plate and a low-temperature lower plate respectively installed on an upper portion of the heat source, wherein the upper portion of the blank is disposed between the high-temperature upper plate and the high-temperature lower plate, and the lower portion of the blank is the low-temperature upper plate and the low-temperature It is characterized in that it is disposed between the lower plates and heated.

In the blank differential heating apparatus of the present invention, an upper heating furnace transfer device is installed so that one end is fixed to the upper heating furnace and the other end of the lower heating furnace is fixed to move the upper heating furnace in a height direction, and the upper heating furnace It characterized in that it further comprises a control unit for controlling the operation of the furnace transfer device.

In the blank differential heating apparatus of the present invention, a plate sensor groove is installed on a surface in contact with the blank on either or both of the upper plate and the lower plate, and the plate sensor groove is formed to extend from the plate surface, A plate sensor formed to have a larger width than the plate sensor groove is installed in the plate sensor groove by forcibly pressing it into the plate sensor groove.

In the blank differential heating apparatus of the present invention, the plate temperature sensor detects the plate temperature and transmits it to the control unit, and the control unit senses the operation of the cylinder and the detected plate is in a state in which the upper heating furnace is moved upward. When the temperature is less than a preset high temperature temperature or low temperature temperature value, the upper heat source or the lower heat source is controlled to maintain a preset high temperature or low temperature temperature value.

In the blank differential heating apparatus of the present invention, the plate sensor groove is characterized in that it is formed in a circular or rectangular cross-sectional shape with an open top.

In the blank differential heating apparatus of the present invention, a cover groove for accommodating a cover portion is formed at an open end of the plate sensor groove.

In the blank differential heating apparatus of the present invention, a heat source portion temperature sensor groove is installed on a surface opposite to a surface in contact with the blank on either or both of the upper plate and the lower plate, and the heat source portion temperature sensor groove is on the upper plate surface. It is formed in a form extending vertically, and a heat source temperature sensor is installed in the heat source sensor groove to detect temperature information of the upper heat source and transmit it to the control unit, and the sensed temperature value is set in advance at the heat source temperature. When the value is greater than the value, the control unit controls a current value applied to the temperature sensor of the heat source unit.

In the blank differential heating apparatus of the present invention, the upper heating furnace conveying device comprises a cylinder, and the cylinder is installed around the outer periphery of the upper heating furnace and the lower heating furnace.

The differential heating apparatus of the present invention makes it possible to easily achieve differential heating of the blank at different temperature values in one apparatus.

In addition, in the present invention, since the plate temperature sensor S1 is installed by press-fitting into the sensor groove G1 formed elongated in the transverse direction of the upper plate 140 and the lower plate 240, respectively, the plates 140 and 240 and the plate temperature sensor (b It acts to increase the adhesion between S1).

As a result, since the heat transfer speed by heat conduction between the plates 140 and 240 and the plate temperature sensor (bS1) is accelerated, it reacts sensitively to the temperature change and the detection speed is also increased, so that the temperature of the plates 140 and 240 is quickly sensed and the control unit 400 ).

Meanwhile, in the present invention, when the controller detects the operation of the cylinder and the upper heating furnace is moved upward, the plate temperature sensed by the plate temperature sensor is detected, and when the temperature is less than a preset temperature, the heat source unit It is controlled to maintain the preset temperature value.

Accordingly, even when the upper heating furnace 100 is transferred to the upper side, the set high temperature temperature (THP1) and the low temperature temperature (TPH2) values of the upper plate 140 and the lower plate 240 are secured and maintained in advance, thereby maintaining the blank (B). The differential heating heat transfer through contact with is reliably guaranteed.

In addition, the control unit 400 senses the temperature of the heat source units 130 and 230 and controls the current value applied to protect the heating wire units 133 and 233 when the temperature of the heat source units 130 and 230 becomes higher than a preset temperature. Will do.

1 is a perspective view of a differential heating apparatus according to an embodiment of the present invention.
2 is a cross-sectional view of a differential heating apparatus according to an embodiment of the present invention.
3 is a perspective view showing an upper heating furnace from the bottom in the differential heating apparatus according to an embodiment of the present invention
4 is a cross-sectional view of an upper heating furnace in the differential heating apparatus according to an embodiment of the present invention.
5 is a bottom view of an upper heating furnace in the differential heating apparatus according to an embodiment of the present invention.
6 is a partial exploded perspective view of an upper heating furnace in the differential heating apparatus according to an embodiment of the present invention.
7 is an exploded perspective view showing a heat source of an upper heating furnace in the differential heating apparatus according to an embodiment of the present invention.
8 is a view showing an upper plate of an upper heating furnace in the differential heating apparatus according to an embodiment of the present invention.
9 is a perspective view showing a lower heating furnace in a plan view in the differential heating apparatus according to an embodiment of the present invention.
10 is a cross-sectional view of a lower heating furnace in the differential heating apparatus according to an embodiment of the present invention.
11 is a partial exploded perspective view of a lower heating furnace in the differential heating apparatus according to an embodiment of the present invention.
12 is a view showing a lower plate of a lower heating furnace in the differential heating apparatus according to an embodiment of the present invention.

The terms or words used in this specification and claims should not be construed as being limited to their usual or dictionary meanings, and the inventor shall appropriately define the concept of the term in order to describe his own invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of the present invention based on the principle that it can be.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

1 is a perspective view of a differential heating apparatus according to an embodiment of the present invention. 2 is a cross-sectional view of a differential heating apparatus according to an embodiment of the present invention.

The blank local heating device includes an upper heating unit 100, a lower heating unit 200 installed under the upper heating furnace 100, and between the upper heating furnace 100 and the lower heating unit 200. It consists of an upper heating furnace transfer device 300 installed in.

3 to 8 are views showing an upper heating furnace in the differential heating apparatus according to an embodiment of the present invention.

The upper heating furnace 100 includes an upper frame 110 and an upper insulating part 120 formed on a bottom surface of the upper frame 110.

The upper frame 110 is made of a metal material, the lower interior is formed in the shape of an empty box, and the partition 111 is installed therein.

The upper insulating part 120 is formed on the bottom surface and circumference of the upper frame 110 and is made of an insulating material such as ceramic wool.

An upper heat source unit 130 is installed inside the upper frame 110.

The upper heat source 130 includes a plurality of installation pins 131 installed on the bottom surface of the upper frame 110, an insulation portion 132 installed at an end of the installation pin 131, and the insulation portion 132 It consists of an upper heating wire portion 133 wound around.

The upper heating wire part 133 is formed in plural and is controlled by the control unit 400, and is formed so that the temperature is controlled differently depending on the group in order to control the temperature.

In this embodiment, the upper heating wire portion 133 is divided into six in total by temperature control, the first row and the second row in the horizontal direction are controlled by the high-temperature heating wire portion 133H, and the third row in the horizontal direction is the low-temperature heating wire portion 130L. ).

The horizontal portion of the b-shaped guide 134 is fixed to the bottom portion of the upper frame 110, and the installation pin 131 is installed to support the vertical portion of the guide 134.

The insulating portion 132 is preferably formed in a bobbin shape because the upper heating wire portion 133 is formed in a strip shape, which is advantageous for winding it.

The insulating part 132 is installed at the end of the installation pin 133 by a pin P.

An upper plate 140 is installed below the upper heating wire part 133, which is fixed by a plate mounting pin 141 fixed to the bottom surface of the upper frame 110.

The upper plate 140 is formed of a metal material for heat transfer through a heat conduction method to the blank (B).

Each upper plate 140 is formed to correspond to each upper heat source 130, and the upper plate 140 includes a high-temperature upper plate 140H and a low-temperature heating wire installed below the high-temperature heating wire part 133H. It consists of a low temperature upper plate (140L) installed in the lower portion of (133L).

Sensor grooves G1 and G2 into which the temperature sensors S1 and S2 are inserted and installed are formed in the upper and lower surfaces of each of the upper plates 140.

The sensor grooves G1 and G2 have a circular or rectangular cross section and are formed to extend in the transverse direction.

The temperature sensors S1 and S2 are thermocouple type known temperature sensors and are formed to extend in the longitudinal direction so as to correspond to the sensor groove G.

The width of the temperature sensors (S1, S2) is formed larger than the sensor grooves (G1, G2) and is installed in a manner that is forced into the sensor grooves (G1, G2) to improve the thermal conductivity with the upper plate (140). Will have.

Alternatively, in some cases, it is possible to form and install a cover C covering the temperature sensors S1 and S2.

The heat source temperature sensor S2 installed in the heat source sensor groove G2 formed on the upper plate 140 senses the temperature of the upper heating wire 133 and this temperature information is transmitted to the controller 400.

The plate temperature sensor S1 installed in the plate sensor groove G1 formed under the upper plate 140 detects the temperature of the upper plate 140 and this temperature information is transmitted to the control unit 400.

9 to 12 are views showing a lower heating furnace in the differential heating apparatus according to an embodiment of the present invention.

The lower heating furnace 200 includes a lower frame 210 and a lower heat insulating part 220 formed on a bottom surface of the lower frame 210.

The lower frame 210 is also made of a metal material, and the upper interior is formed in the shape of an empty box.

A bottom heat insulating part 211 is formed on the bottom of the lower frame 210, and in this embodiment, the bottom heat insulating part 211 is formed in two stages.

A lower heat insulating part 220 is formed around the inner circumference of the lower frame 210 on the upper surface of the bottom heat insulating part 211, and as in the case of the upper heat insulating part 120, it is made of an insulating material such as ceramic wool.

A partition wall part 212 is installed inside the frame 110 of the bottom heat insulating part 211, and a lower heat source part 230 is installed inside each partition wall part 212.

The lower heat source 230 includes a pin mounting plate 231 installed on the bottom surface, an installation pin 232 installed on the upper portion of the pin mounting plate 231, and a lower heating wire part wound around the installation pin 232 ( 233).

The lower heating wire part 233 is configured in the same manner as the upper heating wire part 133 by temperature control. That is, it is divided into a total of six, and the first row and the second row in the horizontal direction are controlled by the high-temperature heating wire unit 233H, and the third row in the transverse direction is controlled by the low-temperature heating wire unit 233L.

A support 213 is formed inside the partition wall portion of the bottom insulation 211, and the lower plate 240 is supported by the support 213.

The lower plate 240 is also formed of a metal material for heat transfer through a heat conduction method to the blank (B).

Since each lower plate 240 is formed to correspond to each lower heating wire 233, the lower plate 240 includes a high-temperature lower plate 240H and a low-temperature heating wire installed under the high-temperature heating wire 233H. It consists of a low-temperature lower plate (240L) installed under the lower portion of the 233L.

Sensor grooves G1 and G2 into which the temperature sensors S1 and S2 are inserted and installed are also formed on the upper and lower surfaces of each of the lower plates 240.

As in the case of the upper plate 140, the sensor grooves G1 and G2 have a circular or rectangular cross section and are formed to extend in the transverse direction.

The temperature sensors (S1, S2) are installed in a manner that is forced into the sensor grooves (G1, G2) by forming a larger width than the sensor grooves (G1, G2), so that the thermal conductivity with the lower plate 240 is improved. do.

Alternatively, in some cases, it is possible to form and install a cover C covering the temperature sensors S1.S2.

The temperature sensors S1 and S2 use a known thermocouple type temperature sensor.

The plate temperature sensor S1 installed in the sensor groove G1 formed on the lower plate 240 detects the temperature of the lower plate 240 and this temperature information is transmitted to the controller 400.

The heat source temperature sensor S2 installed in the heat source sensor groove G2 formed under the lower plate 240 senses the temperature of the lower heating wire 233 and this temperature information is transmitted to the controller 400.

The upper heating furnace transfer device 300 includes a cylinder part 310 and a guide part 320.

The cylinder unit 310 is connected so that the cylinder 311 is installed in the lower heating furnace 200 and the rod 312 is installed in the upper heating furnace 100 and controlled to the control unit 400.

In the guide part 320, the lower part of the vertical bar 322 is fixed to the fixing part 321 of the lower heating furnace 200, and the upper part of the vertical bar 322 is a slider 323 fixed to the upper heating furnace 100. ) Is inserted and installed.

In the present embodiment, the upper heating furnace transfer device is formed in a cylinder type, but is not limited thereto, and other devices may be used as long as the upper heating furnace is relatively transferred in the height direction with respect to the lower heating furnace.

Next, the operation of the differential heating device configured as described above will be described.

First, when the cylinder 310 is operated by the control unit 400, the upper heating furnace 100 moves upward, thereby forming a space between the lower heating furnace 200 and the lower heating furnace 200.

The blank (B) is inserted in the transverse direction by a transfer device (not shown) into the interior of the space, and the upper portion (B1) of the blank (B) is disposed on the high temperature lower plate (240H) and the high temperature upper plate (140H), The lower portion B2 of the blank B is disposed on the low temperature lower plate 240L and the low temperature upper plate 140L (see FIG. 9 ).

In this embodiment, a center pillar applied to a vehicle body of an automobile is used as the blank B.

When the center pillar is used as the blank (B), the upper part (B1) must be formed to have high strength to protect the occupant's head and upper body, and the lower part (B2) must be formed to have low strength to protect the collision energy in the event of a collision. .

Next, as the upper heating furnace 100 moves downward by the operation of the cylinder 500, the blank B is pressed between the upper plate 140 and the lower plate 240 and is mainly heated by a heat conduction method.

The blank (B) is usually pressurized with a maximum force of 40N, and the heating time is usually 15 to 30 seconds.

In the differential heating apparatus of the present invention, the upper portion (B1) of the blank (B) is heated to a high temperature of 950 ℃ by the high temperature upper plate (140H) and the high temperature lower plate (240H), the lower portion (B2) of the blank (B) It is heated to a low temperature of about 650° C. by the low temperature upper plate 140L and the low temperature lower plate 240L.

By this action, the upper (B1) and lower (B2) of the blank (B) in one device has an effect of differential heating to different temperatures within a short time.

Next, the differentially heated blank B is removed from the inside of the differential heating device by a transfer device (not shown).

In the differential heating apparatus of the present invention, the upper heating furnace 100 is frequently moved upward.

Before the differential heating process of the blank (B), the upper heating furnace 100 is maintained in a state transferred to the top for insertion of the blank (B), and after the differential heating process of the blank (B), the differentially heated blank (B) ), it is transferred upwards once more to remove it.

That is, in the present invention, a process in which the upper heating furnace 100 moves upward occurs frequently at least 2-3 times per minute, and there is a possibility that the heat source may be cooled, so there is a need to prevent this. .

The differential heating apparatus of the present invention has a high processing speed and a sufficient strength value is secured by changing the structure of the blank (B) of a metallic material that is differentially heated when operating in a state where the temperature of the heat source portion is lowered without being able to quickly adjust the temperature of the heat source. Problems such as not being able to do so occur.

In the case of a continuous furnace or an intermittent furnace, which is a general heating device, since one differential device does not heat differently as in the present invention, the internal temperature is always maintained at a single constant temperature, so there is little need for this. .

Accordingly, in the present invention, the upper and lower plates 140 and 240 are controlled to have a preset temperature value before contacting the blank B.

In the present invention, when the control unit 400 detects that the upper heating furnace 100 has been moved upward by operating the cylinder unit 310, the temperature value measured through the plate temperature sensor S1 is preset to the upper plate ( 140) and whether it is lower than the high temperature temperature T1 and the low temperature temperature T2 of the lower plate 240 is determined.

When lower than the preset high temperature temperature (T1) and low temperature temperature (T2), the control unit 400 changes the current value applied to the heating wire portions 133 and 233 so that the plates 140 and 240 are changed before the differential heating operation of the next blank B. It serves to maintain a preset high temperature temperature (T1) and low temperature temperature (T2).

Through this action, the set high temperature temperature (T1) and low temperature temperature (T2) values of the upper plate 140 and the lower plate 240 are secured and maintained in advance even in a state in which the upper heating furnace 100 is transferred to the upper side, thereby maintaining the blank ( The differential heating heat transfer through contact with B) is reliably guaranteed.

The plate temperature control is performed in the same way even in the case of a temperature drop due to initial contact with the low-temperature blank B, thereby always maintaining a constant temperature required for heat treatment of the blank metal material through differential heating.

In addition, the control unit 400 senses the temperature of the heat source units 130 and 230 and controls the current value applied to protect the heating wire units 133 and 233 when the temperature of the heat source units 130 and 230 becomes higher than a preset temperature. Will do.

On the other hand, in order to properly operate the differential heating apparatus of the present invention as described above, a rapid temperature measurement of the plate is required.

In the present invention, a plate temperature sensor (S1) having a width larger than that of the plate sensor groove (G1) is forcibly pressed into the sensor groove (G1) formed long in the transverse direction of the upper plate 140 and the lower plate 240, respectively. Is installed.

Accordingly, since the adhesion between the plates 140 and 240 and the plate temperature sensor S1 is increased, the temperature is quickly measured by heat conduction and transmitted to the control unit 400.

This rapid temperature measurement action enables rapid high and low temperature control of the plate, thereby securing the reliability of the device.

The embodiments described in the present specification and the configurations shown in the drawings are only one of the most preferred embodiments of the present invention, and do not represent all the technical spirit of the present invention. It should be understood that there may be equivalents and variations.

100: upper heating furnace 200: lower heating furnace
300: upper transfer device 400: control unit

Claims (8)

As a differential heating device for partially heating the blank to a different temperature,
With an upper heating furnace,
It consists of a lower heating furnace installed below the upper heating furnace,
The upper heating furnace is formed to be movable upward with respect to the lower heating furnace,
The upper heating furnace,
A plurality of upper heat source parts composed of high and low temperatures,
Including an upper plate consisting of a high temperature upper plate and a low temperature upper plate respectively installed under the upper heat source portion of the high and low temperature,
The lower heating furnace,
A plurality of lower heat source units that are configured at high and low temperatures corresponding to the plurality of upper heat source units and are installed at the lower portion,
And a lower plate comprising a high temperature lower plate and a low temperature lower plate respectively installed above the high and low temperature lower heat source portions,
The blank differential heating apparatus, characterized in that the upper part of the blank is disposed between the high temperature upper plate and the high temperature lower plate, and the lower part of the blank is disposed between the low temperature upper plate and the low temperature lower plate to be heated. The method according to claim 1,
An upper heating furnace transfer device that is installed such that one end is fixed to the upper heating furnace and the other end of the lower heating furnace is fixed to move the upper heating furnace in a height direction;
A blank differential heating device, characterized in that it further comprises a control unit for controlling the operation of the upper heating furnace transfer device. The method according to claim 2,
A plate sensor groove is installed on a surface in contact with the blank on either or both of the upper plate and the lower plate,
The plate sensor groove is formed to extend from the plate surface,
A blank differential heating apparatus, characterized in that a plate sensor formed to have a larger width than the plate sensor groove is installed in the plate sensor groove by forcibly pressing it into the plate sensor groove. The method of claim 3,
The plate temperature sensor senses the plate temperature and transmits it to the control unit,
The controller detects the operation of the cylinder and controls the upper or lower heat source to control the upper or lower heat source when the detected plate temperature is less than or equal to a preset high temperature or low temperature while the upper heating furnace is moved upward. Or a blank differential heating device, characterized in that to maintain a low temperature temperature value. The method according to claim 4,
The plate sensor groove is a blank differential heating apparatus, characterized in that formed in a circular or rectangular cross-sectional shape with an open top. The method of claim 5,
A blank differential heating apparatus, characterized in that a cover groove for accommodating the cover part is formed at an open end of the plate sensor groove. The method of claim 6,
A heat source portion temperature sensor groove is installed on either or both sides of the upper plate and the lower plate on a surface in contact with the blank and on the opposite surface,
The heat source part temperature sensor groove is formed in a shape extending longitudinally from the surface of the upper plate,
A heat source temperature sensor is installed in the heat source sensor groove to sense temperature information of the upper heat source and transmit it to the control unit. When the detected temperature value is greater than a preset heat source temperature value, the control unit Blank differential heating apparatus, characterized in that for controlling a current value applied to the heat source part temperature sensor. The method of claim 7,
The upper heating furnace transfer device is made of a cylinder,
The cylinder is a blank differential heating apparatus, characterized in that installed around the outer circumference of the upper heating furnace and the lower heating furnace.

Images