| CN102554040A | 2012-07-11 | |||
| CN102527803A | 2012-07-04 | |||
| US20100116015A1 | 2010-05-13 | |||
| CN103878237A | 2014-06-25 |
| CLAIMS 1. A forming die (1) used in forming high strength steel sheets and used in forming processes in which a blank-holder is needed or not and which heats the flange region (F) except the stamper contact region (M) and which provides realization of the forming process; said forming die (1) is characterized by comprising: - at least one male die (2) which provides forming of the sample (N) whose forming process shall be realized, - at least one heater coil (3) placed between the sample (N) and the male die (2), • adjusted to the preferred temperature value and which emits heat by means of infrared radiation to the periphery thereof, • which provides heating by remaining at the temperature value needed for forming the flange region (F) which remains outside the stamper contact region (M) of the sample (N) to be formed, • which heats the flange region (F), which exists on the sample (N), until reaching the preferred temperature value, • which stops the heating process after the flange region (F) reaches the preferred temperature value and which starts heating of the sample (N) again by reaching a temperature lower than the preferred temperature value of the flange region (F) of the sample (N), - at least one extractor die (4) provided on the surface of the sample (N) which does not contact the heater coil (3) and which provides forming of the surface of the sample (N) where the heater coil (3) does not exist and which provides removal from between the male die (2) and the female die (5) after the forming process, - at least one female die (5) which provides bedding for the extractor die (4) and which provides fixing and removing of the extractor die (4) and which provides forming process of the edge walls of the sample (N). 2. The forming die (1) according to claim 1 , characterized by the heater coil (3) comprising the siliceous sheet spiral (3.1) and the connection end (3.2) and which provides heating of the flange region (F) of the sample (N) in cases where the blankholder is used and is not used. 3. The forming die (1) according to claim 1 , characterized by the heater coil (3) which has siliceous sheet spiral (3.1) which provides heating process thereon and which realizes heating process by means of connecting through the connection end (3.2). 4. The forming die (1) according to claim 1 , characterized by the heater coil (3) which provides heating of the flange region (F) of the sample (N) in case the blankholder is not used and which moves upwardly as preferred from the sample as the male die (2) starts movement during the heating process. 5. The forming die (1) according to claim 4, characterized by the heater coil (3) which heats the flange region (F) of the sample (N) and which diverges from the sample (N) by moving the male die (2) upwardly when the forming process ends. 6. The forming die (1) according to claim 4, characterized by the heater coil (3) which moves in accordance with the male die (2) and provides the heating of the other sample (N) after removal of the formed sample (N) and placing the other sample (N) on the extractor die (4). 7. The forming die (1) according to claim 1 , characterized by the heater coil (3) which provides heating of the flange region (F) of the sample (N) in case the blankholder is used and which rapidly diverges from the sample (N) after the heating process in this case. 8. The forming die (1) according to claim 7, characterized by the heater coil (3) whose blankholder presses the sample (N) simultaneously after departing from the sample (N) and which realizes the forming process. 9. A forming method used in forming high strength steel sheets and used in forming which needs or which does not need blankholder and which heats the flange region (F) which remains outside the stamper contact region (M) and which provides realization of the forming process, said forming method essentially comprises the steps of: - placing primarily the female die (5) onto the operation surface which exists in the operation medium to the forming die (1 ) (101 ), - fixing the female die (5) onto the floor where it is placed (102), - positioning the extractor die (4) to the extractor gap (5.1) in the female die (5) (103), - fixing the sample (N) onto the extractor die (4) with the help of pins through the fixation gaps (4.2) which exist on the extractor die (4) in a manner placed on the female die (5) and the extractor die (4) (104), - approaching the heater coil (3) in a manner corresponding to the flange region (F) of the sample (N) placed onto the extractor die (4) (105), - starting heating of the flange region (F) of the sample (N) by keeping far the heater coil (3) to the sample (N) through a preferred distance (106), - stopping the heating process of the heater coil (3) when the flange region (F) of the sample (N) reaches the preferred temperature value (107), - operating the heater coil (3) again and starting heating of the flange region (F) of the sample (N) as the sample (N) reaches a temperature value which is lower than the preferred temperature value of the sample (N) (108), - drawing the heater coil (3) from the sample (N) and contacting the male die (2) to the stamper contact region (M) which exists on the sample (N) and starting forming of the sample (N) (109), - providing forming of the flange part (F) and the stamper contact part (M) of the sample (N) (110). |
TECHNICAL FIELD
The present invention relates to a forming die and a forming method used in forming high strength steel sheets, which heats the region which remains outside the stamper contact region and thus provides an easier realization of forming process and is used in forming processes in which a blank-holder is needed or not.
PRIOR ART
Different methods are used in forming processes of high strength steel sheets. Said high strength steel sheets are used in automotive, white good, defense industry and many various fields. Therefore, the forming process of high strength steel sheets and production thereof are gaining importance.
In recently designed vehicles, two important subjects become prominent. The first one of these is the usage of high strength steel sheets for providing less damage of the living place at the instant of collision and the second one of these is the usage of sheets which are thinner when compared with the sheets, used presently, for decreasing the weight of vehicle body. The materials which will provide these two characteristics become possible by using high strength steel sheets.
Forming, used in the present systems, becomes possible by firstly heating the die by means of an induction coil embedded into the die for the sheet material in die system and by heating and forming the sample afterwards. This condition leads to increase of the heating duration since this condition shall necessitate heating of the die and the sheet sample at separate times, and therefore, time loss occurs. In the same systems, since the die and the sheet sample are waited to be heated at separate times, it is not possible to heat the preferred region of the sheet sample in an efficient manner. In the present applications, two different temperature meters are used for the press die and for the sheet sample. The usage of the system by means of two different temperature meters makes difficult the applicability of the system. At the same time, this condition leads to the problem that the temperature distribution on the sheet sample is not always as preferred. In the forming die which exists in the subject matter invention, the sample is put under a male die, a heating coil, and the extractor die and the female die are placed under the sample. In the subject matter invention, the sample is placed on the female die and the preferred region of the sample can be heated by means of the heater coil. In the forming die system which exists in the subject matter invention, the heating of the sheet sample is not realized by heating the male and female dies by means of heating coils and subsequently placing the sample sheet between them. In the subject matter invention, the sample is directly heated by means of the heater coil. Thus, very short duration of heating time is required for the heating process. In the invention, which is the subject matter, since a heating which is close to homogenous shall be realized thanks to the inductor coil designed for the flange region of the sheet and is applied on the die, heating shall be controlled by means of a single contactless temperature meter dependent on induction and shall be stopped when the induction reaches the desired temperature. At this point, the applicability and the transformability to automation will become possible.
In the present art, there is no description related to the technical characteristics provided in the present invention and the technical effects provided by the present invention.
OBJECTS OF THE INVENTION
The object of the present invention is to realize a forming die and a forming method which heat the region except the stamper contact region and which increases the forming depth without deteriorating the structure of the sheet sample.
Another object of the present invention is to realize a forming die and a forming method which prevents formation of excessive thinning or necking during forming of high strength steel sheets.
Another object of the present invention is to realize a forming die and a forming method which provides forming process as an alternative to hot forming applications.
Another object of the present invention is to realize a forming die and a forming method which provide decrease of the forming cost as an alternative to hot forming applications. BRIEF DESCRIPTION OF THE INVENTION
The present invention consists of a forming die, male die, heater coil, extractor die and female die defined in the first claim and the other claims dependent on this claim and realized for reaching the object of this invention. Firstly the female die is placed to the operation surface which exists in the operation medium in the forming die. The female die is fixed on the floor where it is placed. Extractor die is positioned to the extractor gap which exists in the female die. The sample is fixed onto the extractor die with the help of pins through the fixation gaps, which exist on the extractor die, in a manner placed onto the female die and the extractor die. The heater coil approaches in a manner corresponding to the flange region of the sample placed onto the extractor die and heats only the flange regions of the sample. The heater coil is kept far from sample at a preferred distance and starts heating the flange region of the sample. The heater coil is drawn back from the sample after heating the flange region of the sample. After the heater coil is drawn from the sample, the male die contacts the stamper contact region on the sample and forces the sample for forming. Thus, the forming process is provided by heating only the flange region of the sample of the heater coil and by forcing the sample towards the female die by the male die afterwards. The heater coil realizes sample heating process within the preferred temperature range. When the flange region of the sample reaches the preferred temperature value, the heater coil stops the heating process. As the sample reaches a temperature value which is lower than the preferred temperature value, the heater coil operates again and starts heating the flange region of the sample. After the first heating process of the heater coil and after drawing of the heater coil from the sample, the male die is actuated and corresponds onto the sample and contacts the sample and provides forming of the stamper contact region and the flange region of the sample.
DETAILED DESCRIPTION OF THE INVENTION
The forming die realized for reaching the object of the present invention is shown in the enclosed figures, where:
Figure 1 is the exploded view of the forming die which exists in the prior art.
Figure 2 is the exploded view of the forming die, which exists in the prior art, from another perspective.
Figure 3 is the exploded view of the forming die. Figure 4 is the perspective view of the male die.
Figure 5 is the perspective view of the heater coil.
Figure 6 is the perspective view of the sample which is to be formed.
Figure 7 is the perspective view of the extractor die.
Figure 8 is the perspective view of the female die.
Figure 9 is the method schema of the forming method.
The parts provided in the figures are numbered one by one, and the correspondence of these numbers has been given below:
1 . Forming die
2. Male die
2.1. Upper forming body
2.2. Drill gap
2.3. Seating surface
3. Fleater coil
3.1. Siliceous sheet spiral
3.2. Connection end
4. Extractor die
4.1. Lower forming body
4.2. Fixation gap
4.3. Forming surface
5. Female die
5.1. Extractor gap N. Sample
M. Stamper contact region F. Flange region
100. Forming method
A forming die (1) used in forming high strength steel sheets and used in forming processes in which a blank-holder is needed or not and which heats the flange region (F) which remains outside the stamper contact region (M) and which provides realization of the forming process, said forming die (1 ) essentially comprises:
- at least one male die (2) which provides forming of the sample (N) whose forming process shall be realized,
- at least one heater coil (3) placed between the sample (N) and the male die (2),
• adjusted to the preferred temperature value and which emits heat by means of infrared radiation to the periphery thereof,
• which provides heating by remaining at the temperature value needed for forming the flange region (F) which remains outside the stamper contact region (M) of the sample (N) which is to be formed,
• which heats the flange region (F), which exists on the sample (N), until reaching the preferred temperature value,
• which stops the heating process after the flange region (F) reaches the preferred temperature value and which starts heating of the sample (N) again by reaching a temperature lower than the preferred temperature value of the flange region (F) of the sample (N),
- at least one extractor die (4) provided on the surface of the sample (N) which does not contact the heater coil (3) and which provides forming of the surface of the sample (N) where the heater coil (3) does not exist and which provides removal from between the male die (2) and the female die (5) after the forming process,
- at least one female die (5) which provides bedding for the extractor die (4) and which provides fixing and removing of the extractor die (4) and which provides forming process of the edge walls of the sample (N).
A forming die (1) which is the subject matter invention is used in forming high strength steel sheets. The forming die (1) is used in forming which need or does not need blankholder. The forming die (1) provides heating of the flange region (F) except the stamper contact region (M) and provides realization of the forming process. In the forming dies (Figures 1-2) which exist in the prior art, for the sheet material, the die can be heated firstly by means of an induction coil embedded into the die and afterwards, the sample can be heated and formed. Since this condition will necessitate heating of the die and the sheet sample at separate times, it leads to increase of the heating duration, and therefore, time loss occurs. In the same systems, since it is waited that the die and the sheet sample are heated at separate times, the preferred region of the sheet sample cannot be heated in an efficient manner. In the forming die samples (Figures 1-2) which exist in the prior art, two different temperature meters are used for the press die and the sheet sample. Usage of the system with two different temperature meters makes the applicability of the system difficult during production. At the same time, this condition leads to the fact that the temperature distribution on the sheet sample is not always as preferred. The forming die (1) which exists in the subject matter invention comprises male die (2), heater coil (3), extractor die (4) and female die (5). The male die (2) which exists in an application of the present invention provides forming of the sample (N) whose forming process shall be realized. The male die (2) can be adjusted such that the geometry thereof depends on the forming process. The male die (2) comprises an upper forming body (2.1), drill gap (2.2) and seating surface (2.3). The male die (2) realizes press forming process such that the seating surface (2.3) which exists on the upper forming body (2.1) corresponds to the stamper contact surface (M) of the sample (N). The male die (2) can be fixed preferably by means of drill gaps (2.2).
The heater coil (3) which exists in this application of the present invention is placed between the sample (N) and the male die (2). The heater coil (3) is adjusted to the preferred temperature value and emits heat to the periphery thereof. The heater coil (3) provides heating of the sample (N), which is to be formed, by holding on the sample (N) at the temperature value needed for forming of the flange region (F) except the stamper contact region (M). The heater coil (3) heats the flange region (F) which exists on the sample (N) until reaching the preferred temperature value. The heater coil (3) stops the heating process after reaching of the flange region (F) to the preferred temperature value and starts reheating the sample (N) again when the flange region (F) of the sample (N) reaches a temperature which is lower than the preferred temperature value. The heater coil (3) comprises siliceous sheet spiral (3.1) and the connection end (3.2). The heater coil (3) provides heating of the flange region (F) of the sample (N) in cases where the blankholder is used and is not used. There is siliceous sheet spiral (3.1) on the heater coil (3). The siliceous sheet spiral (3.1) provides heating process of the heater coil (3). The heater coil (3) connects from the connection end (3.2) and realizes heating process.
In case the blankholder is not used in an application of the present invention, the heater coil (3) provides heating of the flange region (F) of the sample (N). After heating process of the heater coil (3), while the male die (2) moves downwardly, the heater coil (3) moves upwardly as preferred. As the heater coil (3) heats the flange region (F) of the sample (N) and as the forming process ends, the male die (2) moves upwardly and diverges from the sample (N). As the male die (2) is diverged from the sample (N), the formed sample (N) is removed and the other sample (N) is placed instead. As the sample (N) is placed onto the extractor die (4), the heater coil (3) realizes the sample (N) heating process. In an application of the present invention, in case the blankholder is used, the heater coil (3) provides heating of the flange region (F) of the sample (N). In this case where the blankholder is used, the heater coil (3) is rapidly removed from the sample (N) after the heating process. After the heater coil (3) is removed from the sample (N), the blankholder presses the sample (N) simultaneously. As the blankholder compresses the sample, the male die (2) moves downwardly, forming process of the sample (N) is provided.
The extractor die (4), which exists in the subject matter invention, does not exist on the surface of the sample (N) which contacts the heater coil (3). The extractor die (4) provides forming of the surface of the sample (N) where the heater coil (3) does not exist and removal thereof from between the male die (2) and the female die (5) after the forming process. The extractor die (4) comprises lower forming body (4.1), fixation gap (4.2) and forming surface (4.3). The sample (N) is fixed onto the extractor die (4) and is formed. The sample (N) is fixed to the extractor die (4) by passing pins through the fixation gaps (4.2). After heating of the sample (N) by means of the heater coil (3), the male die (2) provides forming by compressing the sample (N).
The female die (5), which exists in the subject matter invention, provides bedding for the extractor die (4). The female die (5) provides fixing and removal of the extractor die (4). The female die (5) provides the forming process of the edge walls of the sample (N). The female die (5) comprises the extractor gap (5.1). The extractor die (4) is placed to the extractor gap (5.1) in the female die (5).
The sheet material, which exists in the subject matter invention, is heated by the flange regions of the sheet material by means of the siliceous sheet spiral (3.1) embedded into the forming die (1). In the subject matter invention, the sheet material shall exist on the forming die (1) and only the preferred region of the sheet material will be heated. In the subject matter invention, since only the sheet sample shall be heated, the duration which passes during heating shall be much shorter and the heating system shall be more compliant to automation. The usability in mass production will be possible. In the subject matter invention, the following process is realized in forming which does not need blankholder (lower control arm). The part sample (N) which is to be formed is placed to the pins at the reference points on the part which functions as the extractor die (4) through the points (at the end part) where drilling process is realized beforehand. Graphite lubricant, which is resistant to temperature, shall be applied onto the female die (5). The siliceous sheeted inductor coil (3.1) placed around the male die (2) shall start heating within the predetermined temperature range of the flange region (F) which is the region which remains outside of the contact region of only the male die (2) of the sample (N) from the predetermined distance. The control of this determined temperature range is provided by means of infrared radiation connected to the induction machine. When the desired temperature is reached, induction heating shall be interrupted and shall start heating again when the temperature decreases. For instance: for a sample (N) to be formed at 350 e C, the temperature value in the infrared radiation control panel connected to the induction device shall be adjusted to 300 e C and heating shall start. When the desired region (flange region (F)) reaches 300 e C, this shall take place between approximately 7 and 10 seconds and shall stop the induction. The stopping temperature of induction takes place approximately between 315-320 e C. When the temperature of the flange region (F) decreases to 299 e C, it shall operate again. Approximately 30 seconds after the first heating, the heater coil (3) moves upwardly, the male die (2) shall move downwardly and shall form the sample.
In the subject matter invention, in case siliceous sheet inductor coil (3.1 ) (press plate) is used, the following process is realized. Only the sample (N) shall be heated to the desired temperature at the desired region (the part except the stamper contact region). The heater coil (3) shall rapidly diverge on the sample (N) (from the die region) before the movement of the male die (2) and the blankholder shall compress the sheet simultaneously and the male die (2) (stamper) shall provide forming and the time duration which takes until the contact of the male die (2) shall change approximately between 3-5 seconds.
The operation of the forming die (1) which exists in the subject matter invention is realized in the following manner. Primarily female die (5) is placed to the operation surface provided in the operation medium in the forming die (1). The female die (5) is fixed on the floor where it is placed. The extractor die (4) is positioned to the extractor gap (5.1) in the female die (5). The sample (N) is fixed onto the extractor die (4) with the help of pins through the fixation gaps (4.2) provided on the extractor die (4) in a manner placing onto the extractor die (4) and the female die (5). The heater coil (3) approaches in a manner corresponding to the flange region (F) of the sample (N) placed on the extractor die (4). The heater coil (3) is kept far from the sample (N) from a preferred distance and starts heating of the flange region (F) of the sample (N). In case the blankholder is not used, the heater coil (3) provides heating of only the flange region (F). The heater coil (3) realizes heating process for the sample (N) within the preferred temperature range. When the flange region (F) of the sample (N) reaches the preferred temperature value, the heater coil (3) stops the heating process. As the sample (N) reaches a temperature value which is lower than the preferred temperature value, the heater coil (3) is operated again and starts heating the flange region (F) of the sample (N). The heater coil (3) is drawn back from the sample (N) after heating of the flange region (F) of the sample (N). After the heater coil (3) is drawn back from the sample (N), the male die (2) contacts the stamper contact region (M) on the sample (N) and provides forming of the sample (N). After the first heating process of the heater coil (3), after the heating coil (3) is drawn back from the sample (N), the male die (2) is moved and corresponds onto the sample (N) and contacts the sample (N) and provides forming of the stamper contact part (M) and the flange part (F) of the sample (N). In case the press plate is used, the heater coil (3) approaches towards the sample (N) at a preferred distance to heat the flange region (F) of the sample (N). By means of said movement of the heater coil (3), after heating of the flange region (F) of the sample (N), the heater coil (3) is drawn back, and after compressing of the sample (N) by the blankholder, the male die (2) is moved and corresponds onto the sample (N) and contacts the sample (N) and provides forming of the flange part (F) and the stamper contact part (M) of the sample (N).
A forming method (100) used in forming high strength steel sheets and used in forming which needs or which does not need blankholder and which heats the flange region (F) which remains outside the stamper contact region (M) and which provides realization of the forming process; said forming method (100) essentially comprises:
- placing primarily the female die (5) onto the operation surface which exists in the operation medium to the forming die (1 ) (101 ),
- fixing the female die (5) onto the floor where it is placed (102),
- positioning the extractor die (4) to the extractor gap (5.1 ) in the female die (5) (103),
- fixing the sample (N) onto the extractor die (4) with the help of pins through the fixation gaps (4.2) which exist on the extractor die (4) in a manner placed on the female die (5) and the extractor die (4) (104),
- approaching the heater coil (3) in a manner corresponding to the flange region (F) of the sample (N) placed onto the extractor die (4) (105),
- starting heating of the flange region (F) of the sample (N) by keeping far the heater coil (3) to the sample (N) through a preferred distance (106),
- stopping the heating process of the heater coil (3) when the flange region (F) of the sample (N) reaches the preferred temperature value (107),
- operating the heater coil (3) again and starting heating of the flange region (F) of the sample (N) as the sample (N) reaches a temperature value which is lower than the preferred temperature value of the sample (N) (108),
- drawing the heater coil (3) from the sample (N) and contacting the male die (2) to the stamper contact region (M) which exists on the sample (N) and starting forming of the sample (N) (109), providing forming of the flange part (F) and the stamper contact part (M) of the sample (N) (110).