Patent Grant
12138676
The present application claims priority under 37 U.S.C. § 371 to International Patent Application No. PCT/IB2020/051713, filed Feb. 28, 2020, which claims priority to and the benefit of Indian patent application No. 201941008005, filed on Feb. 28, 2019. The contents of these applications are hereby incorporated by reference in their entireties.
Present disclosure generally relates to a field of manufacturing technology. Particularly, but not exclusively the present disclosure relates to a system and process for sheet metalworking. Further, embodiments of the disclosure disclose a system and process for supplying electric current to a localized portion of the sheet metal during sheet metalworking.
Manufacturing industries utilize various manufacturing processes for working of various materials. Electrically assisted manufacturing (EAM) process is one such process which falls in to the category of advanced manufacturing processes. During manufacturing, some materials have different physiological properties, and these physiological properties may be altered due to various parameters such as temperature, stress, strain etc during metalworking. Moreover, automotive industry requires different materials with innovative metalworking processes in order to meet the ever changing requirements of the automotive industry. Conventionally, several metalworking techniques such as hot forming and hydroforming provides a wide range of advantages for metalworking. However, these technologies require huge capital investments. Moreover, such technologically advanced installations have several process related issues and are time consuming.
Generally, electrically assisted forming or manufacturing is an alternative metalworking process that includes application of high-density electric pulses during metalworking. Application of electric pulses during metalworking reduces working loads and also spring-back in the metal or workpiece. This phenomenon of reduction in working loads due to the application of electric pulses is known as “electroplastic effect”.
Conventionally, usage of such electric pulses in metalworking processes is well known. Such a manufacturing process involves application of high density electric current pulses throughout length of the metal workpiece [as shown in
Moreover, if any material or the metal workpiece is subjected to electric current pulses, a higher resistance of the workpiece exists which ultimately results in supply of higher electric power for metalworking. This results in a much more expensive metalworking process. Further, as the supply of electric current increases for metalworking, a need for larger thermal insulation may be required in order to maintain or render safe working environment.
The present disclosure is directed to address one or more problems as discussed above.
The information disclosed in this background of the disclosure section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
One or more drawbacks of conventional system for sheet metal working by passing electric current is overcome, and additional advantages are provided through a process as claimed in the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be a part of the claimed disclosure.
In one non-limiting embodiment of the present disclosure, a system for sheet metalworking is disclosed. The system comprising a punch connectable to a press, wherein the punch is configured with a first electrical terminal. A die configured with a die surface is provided in the system, to support sheet metal. A support member is movably disposed in the die. The support member is provided with a second electrical terminal. The support member and the punch contacts a working portion of the sheet metal at an axis to supply electric current to a localized region of the working portion for sheet metalworking.
In an embodiment, the localized region is defined by a contact portion of a tip end of the punch and the tip end of the support member on either sides of the sheet metal.
In an embodiment, the electric current passes from the tip end of the punch and the tip end of the support member to the localized region of the working portion on either sides of the sheet metal.
In an embodiment, the press comprises a punch holder for housing the punch.
In an embodiment, the system comprises an insulation layer in-between the punch holder and the punch to prevent electric conductance.
In an embodiment, the support member displaces within the die along the axis when the punch is operated from a first position to a second position for sheet metalworking.
In an embodiment, the support member at the first position, is in contact at the working portion of the sheet metal before the sheet metalworking.
In an embodiment, the support member maintains the contact with the working portion of the sheet metal in the second position.
In an embodiment, the support member is biased by a resilient member.
In an embodiment, the resilient member is a spring.
In an embodiment, the die comprises a slot for accommodating reciprocal motion of the support member between the first position and the second position.
In an embodiment, an insulation strips provided in-between the support member and the at least one second electrical terminal to prevent electric conductance.
In an embodiment, each of the first electrical terminal and the second electrical terminal is connected to at least one of a positive and a negative terminal of a power source.
In an embodiment, the punch is configured with varying tip diameters for sheet metalworking.
In an embodiment, the sheet metalworking is a plastic deformation process.
In an embodiment, an adapter configured to house at least one load cell for determining load applied on the punch.
In an embodiment, the adapter with the at least one load cell, is secured to the press.
In another non-limiting embodiment, a process for sheet metalworking is disclosed. The process comprises positioning a sheet metal over a die surface of a die. A working portion of the sheet metal contacts a second electrical terminal configured in a support member movably disposed in the die. Operating a punch configured with a first electrical terminal to contact the working portion of the sheet metal, at an axis. Supplying the electric current to the working portion of the sheet metal through the first and second electrical contacts for sheet metalworking.
In an embodiment, supplying the electric current at the working portion aids in sheet metalworking.
In an embodiment, the electric current supplied to the sheet metal has a high current range and a high frequency range.
In an embodiment, the frequency range of the electric current supplied is in the range of 1 Hz to 50 Hz.
In an embodiment, the electric current supplied is in the range of 0 A to 300 A. In an embodiment, the electric current is supplied in pulses to the sheet metal.
In an embodiment, pulses of electric current are supplied by a pulse width modulator (PWM).
It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined to form a further embodiment of the disclosure.
The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
The novel features and characteristics of the disclosure are set forth in the appended description. The disclosure itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will best be understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures. One or more embodiments are now described, by way of example only, with reference to the accompanying figures wherein like reference numerals represent like elements and in which:
The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
While the embodiments of the disclosure are subjected to various modifications and alternative forms, specific embodiment thereof have been shown by way of example in the figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.
It is to be noted that a person skilled in the art would be motivated from the present disclosure to arrive at a system and process of sheet metal working. The system and process for sheet metalworking that is disclosed may vary based on configuration of the sheet metal. However, such modifications should be construed within the scope of the disclosure.
Accordingly, the drawings illustrate only those specific details that are pertinent to understand the embodiments of the present disclosure, so as not to obscure the disclosure with details that will be clear to those of ordinary skill in the art having benefit of the description herein.
The terms “comprises”, “comprising”, or any other variations thereof used in the disclosure, are intended to cover a non-exclusive inclusion, such that a device, system, assembly that comprises a list of components does not include only those components but may include other components not expressly listed or inherent to such system, or assembly, or device. In other words, one or more elements in a system or device proceeded by “comprises . . . a” does not, without more constraints, preclude the existence of other elements or additional elements in the system or device.
The present disclosure provides a system for sheet metalworking. The system comprises a punch that is connectable to a press. The punch is positioned over a die, wherein the die receives the sheet metal for metalworking. The die is also provided with a support member such that, upon receiving the sheet metal, the support member contacts the sheet metal at a working portion. Similarly, a tip end of the punch also contacts the sheet metal at the working portion along a common axis. A first electrical terminal is configured in the punch and a second electrical terminal is connected to the support member. As the press is operated, the punch may be displaced over the sheet metal and comes in contact on the sheet metal at the working portion. At this position, the first electrical terminals and the second electrical terminals are passed with pulsed electric current, and the electric current passes through the sheet metal at the working portion. This aids in metalworking of the sheet metal by reducing the load required for metalworking and also reduces joule heating as the electric current is passed at a localized working portion of the sheet metal.
The present disclosure also provides a process for sheet metalworking. The process includes positioning of the sheet metal over a die such that the working portion of the sheet metal contacts the support member. The sheet metal at a localized region of the working portion is contacted by the tip portion of the punch and the support member along a common axis. The support member is configured to displace upon movement of the sheet metal due to the working of the punch on the sheet metal. As the punch and the support member are provided with first electrical terminal and the second electrical terminal, electric current is passed in pulses, through the working portion in order to perform sheet metalworking. This configuration of the system and process for sheet metalworking reduces joule heating as the electric current is passed at the localized region such as the working portion of the sheet metal rather than the entire length of the sheet metal.
The present disclosure discloses a system and process for metalworking by mitigating heat generated within the sheet metal during metalworking. Also, this process of sheet metalworking is versatile and may use less load for metalworking, while being time efficient and economical. The system and process of the present disclosure also eliminates the need for expensive equipment for sheet metalworking.
The following paragraphs describe the present disclosure with reference to
The system (100) comprises a punch (1) (shown in
In an embodiment, the support member (4) is configured with a second electrical terminal (5), and the second electrical terminal (5) is connected another terminal of the power source (10). A tip end (TE) of the support member (4) is in contact with the sheet metal (SM) provided on the die (3). As the press (P) is operated, the punch (1) with its tip end (TE) comes in contact with the sheet metal (SM) at a localized region (LR) of a working portion (B) of the sheet metal (SM). As the sheet metal (SM) is subjected to metalworking, the tip ends (TE) of the punch (1) and the support member (4) contacts the localized region (LR) of the working portion (B) along an axis (A-A) on either sides of the sheet metal (SM). Also, as the sheet metal (SM) is worked by the punch (1) provided over the die (3), and the support member (4) is always in moving contact with the sheet metal (SM) during metalworking. In an embodiment, the first electrical terminal (2) may be connected to a positive pole of the power source (10) and the second electrical terminal (5) may be connected to a negative pole of the power source (10). In an embodiment, the polarity of the first electrical terminal (2) and the second electrical terminal (5) may be interchanged which is connected to the power source (10).
In an embodiment, as the punch (1) presses down on the sheet metal (SM) on operation of the punch (P), the first electrical terminal (2) and the second electrical terminal (5) receives electric current in the form of pulses from the power source (10). This electric current is concentrated only at the localized region (LR) of the working portion (B) of the sheet metal (SM) and the electric current is localized only at the axis (A-A). In an embodiment, the point of contact for the tip end (TE) of the punch (1) and the tip end (TE) of the support member (4) is at the location where the sheet metal (SM) to be worked. In an example, during bending operation of the sheet metal (SM), the working portion (B) is formed at a V-bend portion of the sheet metal (SM). Moreover, the electric current supplied during metalworking [bending process] passes between the first electrical terminal (2) to the second electrical terminal (5) or vice versa only at the localized region (LR) of the working portion (B) of the sheet metal (SM).
In an embodiment, the passage of electric current may be restricted only to the localized region (LR) of the working portion (B) of the sheet metal (SM). As the punch (1), bends the sheet metal into the die (3), pulsed electric current may be supplied from each of the first electrical terminal (2) and the second electrical terminal (5) from the power source (10). As the load is applied on the press (P), the at least one load cell (11) determines the amount of load being applied on the sheet metal (SM) at any particular interval of metalworking. In an embodiment, the at least one load cell (11) is at least one of a strain gauge based transducer or any other load cell that aids in determination of the load applied on the punch (1).
Referring to
In an embodiment, the die (3) defined with the slot (8) houses the support member (4). The slot (8) may be provided with an insulation layer (7′) similar to the insulation layer (7) provided in-between the punch (1) and the punch holder (6), in order to prevent leakage of the electric current passing through the support member (4) into the die (3). In an embodiment, the second electrical terminal (5) is provided such that, the electrical current passes only through the tip end (TE) portion of the support member (4) and into the sheet metal (SM) at the working portion (B). In an embodiment, the slot (8) defined in the die (3) may be at least one of a square shaped slot (8), a rectangular slot (8) to house the resilient member (22) and the support member (4). During operation of the punch (1) on the sheet metal (SM), the punch (1) deforms or bends the sheet metal (SM) into V-shape form, wherein this bending or deformation of the sheet metal (SM) may be supported by the plurality of fillets (17) defined on the die (3) surface.
In an embodiment, the punch (1) fixed to the punch holder (6) comprises of plurality of varying tip radii [best shown in
In an embodiment, the first electrical terminal (2) connected to the punch (1) is provided with insulation, wherein the insulation is in the form of bush and washer (7a). The insulation bush and washer (7a) prevents any leakage of electric current passing through the first electrical terminal (2) into the adapter (12). A mounting hole (16) is defined on the die (3) in order to receive the insulation rods (15). In an embodiment, the insulation layer (7, 7′), the insulation strips (9) and the insulation bush and washer (7a) may be made of bakelite, elastomers or any electrically insulating material which serves the purpose of preventing electrical conductance or leakage of electric current.
Referring to
In an embodiment, the data acquisition system (21) may be at least one of a computer, a smart phone, or any other programmable device that may receive, analyse and process various critical parameters of the sheet metalworking.
The first electrical terminal (2) and the second electrical terminal (5) provided on each of the punch (1) and the support member (4) respectively, are connected to the programmable pulse generator or the pulse width modulator (18). Based on the operation of the press (P), electric current pulses are passed at the working portion (B) of the sheet metal (SM) [shown in
In an embodiment, the programmable pulse generator or the pulse width modulator (18) may be programmed to generate various shapes of the electric current pulses. As an example, a rectangular shaped pulse is generated with a predetermined frequency. The predetermined frequency ranges from 1 Hz to 50 Hz. However, the frequencies are only aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting not should be considered as limiting. Similarly, the present document highlights the current application in the range of 0-300 A as disclosed in
In an embodiment, the electric current passed through the sheet metal (SM) in pulses, is of a high current, high voltage for metalworking. Due to the high current, high voltage, the load required for sheet metalworking is reduced in comparison with conventional processes.
In an exemplary experimental embodiment, and referring to
Based on the bending metalworking, electric current pulses are passed at the working portion and V-bending operation is carried out on the sheet metal. The thermocouple is fixed to the sheet metal to determine temperature of the C—Mn steel sheet metal at the central portion of the sheet metal. The data acquisition system (100), acquires all the data such as load, temperature data and displays to the user.
Based on various experimental iterations with different electric currents and frequencies, the maximum temperature at the centre of the C—Mn steel sheet metal was 129° C. This, experiment disclosed that, no effect of temperature or higher joule heating was imparted on the sheet metal. In an embodiment, the electric current supplied to the sheet metal (SM) has a high current range and a high frequency range. The frequency of the electric current supplied is in the range of 1 Hz to 50 Hz [as shown in
Similarly, the effect of applying electric current pulses only in the working portion, against applying current along the whole length of sheet metal was carried out.
Table 1 shows force drop and temperature rise based on the above experiments with continuous electric current pulses application. It is noticed that, the process of the present disclosure, i.e. application of electric current pulses in the working portion achieved more than double load drop compared to the conventional processes [i.e. application of current throughout the length of the sheet metal). The overall, results are about 5% higher load drop in comparison with the process employed in the present disclosure. Simultaneously, the maximum temperatures in comparison with the process employed in the present disclosure and the conventional process was insignificant.
Table 2 shows the results two experimental configurations, with a series of single pulses application and corresponding load drops and maximum temperature rise. The load drop increased from 10.5 N to 28 N with each pulse in the present disclosure. It is also noticed that, the single pulse current application has no effect on the load drop at all in the existing method (1) and it might need very high level of electric current pulses to achieve similar load drops of the order 20 N. In the present disclosure, temperature rises only near to the local deformation zone and other areas of the sheet metal are at room temperature. Whereas in the conventional process, temperature rise is present throughout the sheet metal. Therefore, the present disclosure reduces the amount of joule heating compared to conventional processes and still achieves higher load drops compared to conventional processes.
With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.
It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system (100) having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances, where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system (100) having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”
While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201941008005 | Feb 2019 | IN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2020/051713 | 2/28/2020 | WO |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2020/174450 | 9/3/2020 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 1251578 | Riecken | Jan 1918 | A |
| 4532793 | Bezold | Aug 1985 | A |
| 6209381 | Yaguchi | Apr 2001 | B1 |
| 7302821 | Dariavach | Dec 2007 | B1 |
| Number | Date | Country |
|---|---|---|
| 108405727 | Aug 2018 | CN |
| H07155856 | Jun 1995 | JP |
| Entry |
|---|
| International Searching Authority, “International Search Report,” issued in connection with International Patent Application No. PCT/IB2020/051713, dated Sep. 11, 2020. |
| International Searching Authority, “Written Opinion,” issued in connection with International Patent Application No. PCT/IB2020/051713, dated Sep. 11, 2020. |
| Number | Date | Country | |
|---|---|---|---|
| 20230067089 A1 | Mar 2023 | US |
