METHOD AND SYSTEM FOR ELECTROSTATICALLY CHARGING STAMPING LUBRICANT TO CONTROL DEPOSITION
20240017316 ยท 2024-01-18
Assignee
Inventors
Cpc classification
International classification
Abstract
A method of lubricating a sheet of material includes moving the sheet along a first direction and operating a print nozzle to deposit a lubricant on the sheet while the sheet is moving along the first direction. The print nozzle ejects the lubricant in a second direction that is transverse to the first direction and toward a first side of the sheet. The method includes charging the lubricant so that the lubricant ejected from the print nozzle is in the form of charged droplets and applying an external electrical field between the print nozzle and the sheet to attract the charged droplets to the sheet.
Claims
1. A method of lubricating a sheet of material, the method comprising: moving the sheet along a first direction; operating a print nozzle to deposit a lubricant on the sheet while the sheet is moving along the first direction, wherein the print nozzle ejects the lubricant in a second direction that is transverse to the first direction and toward a first side of the sheet; charging the lubricant so that the lubricant ejected from the print nozzle is in the form of charged droplets; and applying an external electrical field between the print nozzle and the sheet to attract the charged droplets to the sheet.
2. The method according to claim 1, further comprising adjusting a velocity of the charged droplets by adjusting the external electric field.
3. The method according to claim 1, wherein a strength of the external electric field is controlled based on a speed of the sheet moving along the first direction.
4. The method according to claim 1, wherein the sheet is a metal material.
5. The method according to claim 1, wherein the lubricant is charged before being ejected from the print nozzle.
6. The method according to claim 1, wherein the lubricant is charged as it is ejected or immediately after being ejected from the print nozzle.
7. The method according to claim 1, wherein the print nozzle is located below the sheet.
8. The method according to claim 1, wherein the external electric field is in the range of 30-120 kV/m.
9. The method according to claim 1, wherein the charged droplets are charged with a positive charge.
10. The method according to claim 9, wherein the positive charge is in the range of 10-200 kV.
11. The method according to claim 1, wherein the charged droplets are charged to within the range of 10-200 kV.
12. The method according to claim 1, wherein the lubricant is charged by a first charging device and the external electric field is provided by a second charging device separate from the first charging device.
13. A method of lubricating a sheet of material, the method comprising: moving the sheet along a first direction; operating a print nozzle to deposit a lubricant on the sheet while the sheet is moving along the first direction, wherein the print nozzle ejects the lubricant in a second direction that is transverse to the first direction and toward a first side of the sheet; charging the lubricant with a first charging device so that the lubricant ejected from the print nozzle is in the form of charged droplets; operating a second charging device to apply an external electrical field between the print nozzle and the sheet to attract the charged droplets to the sheet; and adjusting a velocity of the charged droplets by adjusting a strength of the external electric field.
14. The method according to claim 13, wherein the strength of the external electric field is controlled based on a speed of the sheet moving along the first direction.
15. The method according to claim 13, wherein the print nozzle is located below the sheet.
16. A system for lubricating sheet metal to be formed into a metal component, the system comprising: a print head, including a plurality of nozzles, each nozzle of the plurality of nozzles including an aperture plate, an actuator, and a body, the aperture plate and the body cooperating to define a reservoir configured to hold lubricant, the actuator configured to vibrate the lubricant in the reservoir to eject the lubricant as droplets through an aperture of the aperture plate; a first charging device configured to electrically charge the lubricant; a second charging device configured to produce an external electric field between the print head and the sheet metal; and a control module configured to control operation of the second charging device to selectively adjust a strength of the external electric field.
17. The system according to claim 16, wherein the control module is configured to selectively adjust the strength of the external electric field based on a speed of the sheet moving along a first direction.
18. The system according to claim 16, wherein the first charging device is configured to electrically charge the lubricant before the lubricant is ejected from each nozzle.
19. The system according to claim 16, wherein the first charging device is configured to electrically charge the lubricant as it is ejected or immediately after being ejected from each nozzle.
20. The system according to claim 16, wherein the first charging device is configured to electrically charge the lubricant in the range of 10-200 kV and the external electric field is in the range of 30-120 kV/m.
Description
DRAWINGS
[0020] In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which:
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[0036] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.
DETAILED DESCRIPTION
[0037] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.
[0038] Referring to
[0039] In one form, the sheet metal material 114 can be unrolled from a coil 120 of metal. In one form, the sheet metal material 114 may be cut into predetermined discrete lengths from the coil 120 before being fed through the lubrication system 130 such that discrete, rectangular, flat sheets of metal are fed into the lubrication system 130. In another form, the lubrication system 130 acts on the continuous sheet of metal from the coil 120.
[0040] At the lubrication system 130, lubrication is applied to the sheet metal material 114. The application of the lubrication is controlled by a control module 134, as described in greater detail below. While described herein as a control module 134, it is to be understood that one or more control modules may be used.
[0041] After lubrication, the sheet metal material is fed into a blanker 118 or blanking machine, such as by rollers (not specifically shown but may be similar to those shown in
[0042] In the example provided, the sheet metal blank 122 is a flat sheet having a predefined shape. In an alternative configuration, not specifically shown, the sheet metal blank 122 may include minor or initial bends. In the specific example provided, the metal component 110 is a vehicle body or frame panel and the cut-outs 124 are rough openings that correspond to door and/or window openings in the final metal component 110, though other types of metal components can be manufactured.
[0043] While illustrated and described herein as lubricating the sheet metal material 114 before the blanking process of the blanker 118, in an alternative configuration, not specifically illustrated, the lubrication system 130 can be after the blanker 118 such that the lubrication is applied in a similar manner as that discussed below but to the sheet metal blank 122 after being processed by the blanker 118. In yet another configuration, not specifically illustrated, the lubrication system similar to lubrication system 130 can be included before and after the blanker 118 such that the lubrication applied before the blanker 118 can be specific to the blanking operation and the lubrication applied after the blanker 118 can be specific to the subsequent stamping operations.
[0044] With additional reference to
[0045] In the example provided, the print head 210 is stationary and the sheet metal material 114 is translated past the print head 210 while the print head 210 ejects lubrication onto the sheet metal material 114 as the sheet metal material 114 is moving past. For example, the sheet metal material 114 may be translated by rollers 222, though other configurations can be used. In the example provided, the print head 210 is located above the path of the sheet metal material 114 such that the print head 210 sprays lubricant on a top surface of the sheet metal material 114. In an alternative configuration, such as those shown in
[0046] One or more sensors 226 can be in communication with the control module 134 and configured to detect the sheet metal material 114, such as detecting its position in the X and/or Y direction relative to the print head 210 for example. The sensors 226 may also be configured to detect the width of the sheet metal material 114.
[0047] While the sheet metal material 114 is illustrated as translating horizontally, other orientations can be used. While pairs of rollers 222 are illustrated such that the sheet metal material 114 passes between two rollers 222 of each pair, other configurations can be used, e.g., rollers 222 only being located below the sheet metal material 114.
[0048] Returning to
[0049] In yet another alternative configuration, not specifically illustrated, the lubrication system 130 can be located after the stack 138 of sheet metal blanks and before the stamping press 142.
[0050] The stamping press 142 performs stamping operations on the sheet metal blank 122. These stamping operations can press the sheet metal blank 122 between dies (not specifically shown) that can shape the sheet metal blank 122 into three-dimensional shapes. The stamping operations may optionally remove additional offal or scrap 144. While one stamping press 142 is schematically illustrated, a plurality of stamping presses can be used to achieve the final three-dimensional shape of the metal component 110.
[0051] Referring to
[0052] The print head 210 includes a first set of nozzles (i.e., the nozzles 310 within dashed line region 314) connected to a lubrication source 318, which may include at least a reservoir (not specifically shown) and a pump (not specifically shown) for example. In the example provided, the first set of nozzles 314 may be arranged in an array along the Y-direction while the sheet metal material 114 (
[0053] In the example provided, the second set of nozzles 322 may be connected to a second lubrication source 326 that may optionally be separate from the first lubrication source 318. The first lubrication source 318 and the second lubrication source 326 can optionally supply different types of lubrication. In one form, the first lubrication source 318 provides a liquid lubricant and the second lubrication source 326 provides a solid lubricant such as a powder or dry-film wax for example. In an alternative configuration, not specifically shown, both the first set of nozzles 314 and the second set of nozzles 322 can be connected to the same lubrication source. While two arrays of nozzles 310 are illustrated, the nozzles 310 can be arranged in other configurations.
[0054] The nozzles 310 can be any suitable type of nozzle configured to be independently controlled and to print the lubrication with precision providing pixels of lubrication between 20 micrometers and 3,000 micrometers in size.
[0055] With reference to
[0056] In some alternative forms, the actuator 414 may be attached to the body 418 separate from the aperture plate 410, such as within the reservoir 422 for example, and configured to produce acoustic pressure waves in the lubricant that is within the reservoir 422. The acoustic pressure waves can cause the lubricant to be ejected from the nozzle 310 through the apertures 430.
[0057] In still other forms, the nozzles 310 can be other types of printing nozzles known in the art. For example, the nozzles 310 can be piezoelectric jetting nozzles, thermal jetting nozzles, valve jetting nozzles or other ink jet nozzles that are capable of printing pixels of between 20 micrometers and 3,000 micrometers in size.
[0058] Returning to
[0059] In one form, the test stamping process 152 is a simulated stamping process performed on a computer (not specifically shown) such that the test sheet metal blank is a computer model of the actual sheet metal blank 122. The test sheet metal blank is loaded in a computer program that performs a simulation (e.g., finite element analysis) of the stamping process on the test sheet metal blank (i.e., the computer model). The computer program generates a strain map from the simulation performed on the test sheet metal blank. The strain map 810 (
[0060] A computer (e.g., the same computer or a different computer than the one that generated the strain map 810) can then generate the lubrication program based on the strain map 810. For example, the lubrication program can be configured to provide higher thicknesses of lubrication to locations where the strain map 810 indicates high levels of strain. Additionally, or alternatively, the lubrication program can be configured to provide higher levels of lubrication where the resulting material is thinner and/or where the simulation predicts cracking may occur.
[0061] In one form, the lubrication program can reduce or eliminate lubrication from being applied within a predetermined distance from the edges of the sheet metal blank 122 such that a border 814 (
[0062] In an alternative form, the test sheet metal blank can be a physical sheet metal blank (similar to sheet metal blank 122) and the test stamping process 152 can include physically stamping the test sheet metal blank. The stamped test sheet metal blank can then be measured or scanned to generate the strain map 810. For example, the stamped test sheet metal blank can be physically measured with tools or scanned with three-dimensional scanners (not shown) such as laser scanners, radar scanners, optical scanners, or other suitable scanners. The measurements can indicate strain at different locations along the test sheet metal blank. For example, the measurements can measure changes in thickness, and/or locations where cracking occurred. The measured values, correlated to their locations on the test sheet metal blank, result in the strain map 810. The strain map 810 is then used to generate the lubrication program 148 in a manner similar to that described above with reference to the computer simulated test stamping process 152.
[0063] In one form, the test stamping process can optionally include test runs (e.g., actual physical tests or computer simulated test runs) of both the stamping process and the blanking process such that the strain map 810 is based on the operations of both the blanker 118 and the stamping press 142 and the lubrication program is based on both operations.
[0064] The control module 134 uses the lubrication program to control selective activation of the nozzles 310 to apply the lubrication to the actual sheet metal material 114 such that the lubrication is applied non-uniformly across the sheet metal material 114, in a manner that correlates to the strain map 810.
[0065] The metal component 110, after one or more stamping operations, can optionally be scanned 160 (e.g., optical scanners, laser scanners, etc.) and any defects can be used to modify the lubrication program to generate a new lubrication program 148 for the control module 134. In one form, the result of the scan 160 may be utilized by machine learning to automatically adjust the lubrication program.
[0066] Referring to
[0067] In one form, the lubrication program can be configured to apply lubrication according to a first thickness to a first region 818 of the sheet metal material 114 and to apply the lubrication according to a second thickness to a second region 822 of the sheet metal material 114, the first thickness being thicker than the second thickness. In one form, the first region 818 of the sheet metal material 114 correlates to a region of the strain map 810 that has higher strain than a region of the strain map 810 that correlates to the second region 822 of the sheet metal material 114. Any number of regions having different strain levels, and consequently, different lubrication thicknesses or types can be used based on the resolution of the simulation or measurements and the resolution of the print head 210.
[0068] Referring to
[0069] In one form, illustrated in
[0070] In another form, the lubrication program can be configured to change the spacing between the pixels 510 and/or change the size of the pixels 510 (i.e., still within the range of 20 micrometers to 3,000 micrometers) across the sheet metal material 114 based on the strain map 810.
[0071] In another form, illustrated in
[0072] The barcode 610 or 710 can include any suitable information. In one form, the barcode 610 or 710 may include lot number and/or dates of the metal and/or of the lubrication, though other information can be used. For example, the information may be indicative of a vehicle part number and/or location of manufacture, among other information. While machine scannable barcodes are shown, other information may be printed in addition to or instead of a barcode, such as text or symbols readable by a person for example.
[0073] In the examples provided, the barcode 610 and 710 is applied with a dry-film lubricant, though other configurations can be used.
[0074] In another form, referring again to
[0075] Additionally, the precise print head 210 and individual control of the nozzles 310 of the print head 210 permit different sizes and shapes of sheet metal material or blanks to be used with the same lubrication system 130 by merely changing the lubrication program.
[0076] Referring to
[0077] In the example provided, the nozzles 910 are arranged generally in the center of the path that the sheet metal material 114 will pass, though other configurations can be used. The nozzles 910 all provide lubrication at the same time in a uniform amount. The control module 134 can be in communication with a valve 914 between the lubricant supply 326 and the nozzles 910. When the valve 914 is open, the lubricant flows from all of the nozzles 910.
[0078] In the example provided, the lubricant supply 326 is separate from the lubricant supply 318, though other configurations can be used. In one form, the lubricant supplies 318, 326 provide the same type of lubricant. In an alternative form, the lubricant supplies 318, 326 provide different types of lubricant. In an alternative configuration some of the nozzles 910 may have more apertures or different sized apertures such that different amounts of lubricant can exit from each nozzle 910 despite all of the nozzles operating at the same time based on the condition of the valve 914.
[0079] The nozzles 910 can optionally be electrostatically charged to charge the lubrication leaving the nozzles 910 so as to be attracted to the sheet metal material 114. In one configuration, the individually controllable nozzles 310 are not electrostatically charged. In another configuration, the individually controllable nozzles 310 may be electrostatically charged.
[0080] In the example provided, the individually controllable nozzles 310 are arranged in an array (similar to
[0081] As a result, different numbers of the nozzles 310 can selectively be turned on or off to avoid overspray when the lubrication system 130-2 or 130-3 is used for different width sheet metal components. Thus, the lubrication system 130-2 or 130-3 may optionally provide lubrication for different widths of sheet metal and may provide the lubrication as a uniform or non-uniform distribution. Alternatively, the lubrication system 130-2 or 130-3 can provide reduced lubrication near the edges while providing either a uniform or non-uniform distribution across the middle. In the case of lubrication system 130-3, non-uniform distribution across the middle can be achieved with predetermined different numbers or sizes of apertures among the nozzles 910.
[0082] Referring to
[0083] While not shown, an additional print head (e.g., upper print head) may optionally be disposed above the sheet metal material 114 to spray the top surface thereof.
[0084] The charging device 1110 is configured to electrically charge the lubrication particles as they traverse the air gap between the print head 210 and the sheet metal material 114. In the form in which the optional upper print head is included, the upper print head may optionally have a corresponding charging device (not shown) or not.
[0085] In the example provided, the charging device 1110 includes one or more plates 1114 that create an electric field (schematically illustrated by the opposing arrows between the plates 114) that is configured to charge the particles and is controlled by the control module 134. The plates 1114 can be coupled to the print head 210 or can be separate therefrom and disposed between the print head 210 and the sheet metal material 114. In the example provided, the charging device 1110 applies a positive charge to the particles. In another form, the charging device applies a negative charge to the particles. In one form, the charging device 1110 can charge the lubrication particles to a charge in the range of 10-200 kV.
[0086] Referring to
[0087] While not shown, an additional print head (i.e., upper print head) may optionally be disposed above the sheet metal material 114 to spray the top surface thereof.
[0088] The charging device 1210 is configured to electrically charge the lubrication before it leaves the print head 210. In one form, the charging device 1210 is between a lubrication reservoir 1214 and the print head 210, such as within the lubrication recirculation system 214 for example. In another form, not specifically shown, the charging device 1210 is attached to or within the print head 210. In one form, the charging device 1210 can charge the lubrication particles in the range of 10-200 kV. In the form in which the optional upper print head is included, the upper print head may optionally receive charged lubrication from the same charging device 1210 as the print head 210 or the upper print head may have a corresponding charging device (not shown) or may be configured to not spray charged lubricant.
[0089] Referring to both
[0090] The control module 134 can be configured to control and selectively vary an external electric field (schematically illustrated by the arrows pointing in the positive Z direction) applied between the print head 210 and the sheet metal material 114. In one form, this electric field is applied in the range of 0-120 kV/m, and in some forms more specifically between 30-120 kV/m.
[0091] In one form, the voltage applied by the charging device 1110 or 1210 (e.g., when the charging device 1110 1210 is mounted to or proximate the print head 210) can be varied to selectively vary the electric field between the print head 210 and the sheet metal material 114. For example, the charging device 1110 can create the electric field between the print head 210 and the sheet metal material 114 or if the charging device 1210 is mounted to the print head 210, it can charge the print head 210 to create the electric field between the print head 210 and the sheet metal material 114.
[0092] In another form, the control module 134 can control application of an external electric field via an optional external charging device 1122 or 1222. The external charging device 1122 or 1222 may be in addition to the charging device 1110 or 1210 and is not specifically configured to charge the particles of lubrication. For example, in one form, the charging device 1122 or 1222 may be further from the apertures 430 (labeled in
[0093] The control module 134 can selectively vary the external electrical field to selectively vary the speed at which the charged lubricant particles fly toward the sheet metal material 114. As such, the velocity of the lubricant particles can be controlled and varied without the need to change the waveform or voltage of the actuators 414 (
[0094] While shown with the print head 210 ejecting the droplets perpendicularly to the movement of the sheet metal material 114, other configurations can be used, such as at a non-perpendicular angle, for example.
[0095] Referring to
[0096] Referring to
[0097] Referring to
[0098] Referring to
[0099] Unless otherwise expressly indicated herein, all numerical values indicating mechanical/thermal properties, compositional percentages, dimensions and/or tolerances, or other characteristics are to be understood as modified by the word about or approximately in describing the scope of the present disclosure. This modification is desired for various reasons including industrial practice, material, manufacturing, and assembly tolerances, and testing capability.
[0100] As used herein, the phrase at least one of A, B, and C should be construed to mean a logical (A OR B OR C), using a non-exclusive logical OR, and should not be construed to mean at least one of A, at least one of B, and at least one of C.
[0101] In this application, the term controller and/or module and/or control module may refer to, be part of, or include: an Application Specific Integrated Circuit (ASIC); a digital, analog, or mixed analog/digital discrete circuit; a digital, analog, or mixed analog/digital integrated circuit; a combinational logic circuit; a field programmable gate array (FPGA); a processor circuit (shared, dedicated, or group) that executes code; a memory circuit (shared, dedicated, or group) that stores code executed by the processor circuit; other suitable hardware components (e.g., op amp circuit integrator as part of the heat flux data module) that provide the described functionality; or a combination of some or all of the above, such as in a system-on-chip.
[0102] The term memory is a subset of the term computer-readable medium. The term computer-readable medium, as used herein, does not encompass transitory electrical or electromagnetic signals propagating through a medium (such as on a carrier wave); the term computer-readable medium may therefore be considered tangible and non-transitory. Non-limiting examples of a non-transitory, tangible computer-readable medium are nonvolatile memory circuits (such as a flash memory circuit, an erasable programmable read-only memory circuit, or a mask read-only circuit), volatile memory circuits (such as a static random access memory circuit or a dynamic random access memory circuit), magnetic storage media (such as an analog or digital magnetic tape or a hard disk drive), and optical storage media (such as a CD, a DVD, or a Blu-ray Disc).
[0103] The apparatuses and methods described in this application may be partially or fully implemented by a special purpose computer created by configuring a general-purpose computer to execute one or more particular functions embodied in computer programs. The functional blocks, flowchart components, and other elements described above serve as software specifications, which can be translated into the computer programs by the routine work of a skilled technician or programmer.
[0104] The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the substance of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.