Electrostatic pad and method of electrostatic adhesion between electrostatic pad and sheet of material

Abstract

The invention relates to an electrostatic pad and a method of electrostatic attachment between an electrostatic pad and a sheet of material. The electrostatic pad includes a first planar array of first electrodes arranged in a first pattern and a second planar array of second electrodes arranged in a second pattern different from the first pattern, where the first planar array and the second planar array are arranged parallel to each other. A third layer of electrically insulating material may be sandwiched between the first and second planar arrays of respective first and second electrodes.

Description

Technical Field

[0001] The present disclosure relates generally to electrostatic mats, and more particularly, to electrostatic mats for picking up dry carbon fiber sheets. Background Art

[0002] The electrostatic mat may be powered on to create a voltage differential across it, thereby presenting an electrostatic adhesion potential on the mat. This electrostatic adhesion may then be used to attract and hold a dry carbon fabric sheet in contact with the mat, which may then be used to transport the sheet from one location to another. Once the sheet is transported, the mat may be de-energized, which causes the voltage differential and adhesion potential to decrease, causing the sheet to fall from the mat.

[0003] This process can be repeated for other carbon sheets, which is useful in two-dimensional (2D) and three-dimensional (3D) pick and place operations. However, conventional methods and electrostatic pad designs used in this process have limitations in terms of the adhesion strength developed. Summary of the invention

[0004] According to one embodiment, an electrostatic pad includes a first planar array of first electrodes arranged in a first pattern and a second planar array of second electrodes arranged in a second pattern different from the first pattern, wherein the first planar array and the second planar array are arranged parallel to each other.

[0005] In this embodiment, one of the first planar array and the second planar array may be arranged directly above the other of the first planar array and the second planar array.The first electrode may have a first polarity, and the second electrode may have a second polarity opposite to the first polarity.

[0006] The electrostatic pad may also include a third layer of electrically insulating material sandwiched between the first planar array and the second planar array. The third layer may be in contact with each of the first planar array and the second planar array of corresponding first and second electrodes, and the third layer may be in contact with the first and second edges of the first and second electrodes, respectively. The third layer may have a third layer thickness of approximately 25 microns.

[0007] The second pattern may be a reverse of the first pattern. Additionally, the first pattern and the second pattern may be a first checkerboard pattern and a second checkerboard pattern, respectively.

[0008] The electrostatic pad may also include one or more first electrical leads in electrical communication with the first electrode and one or more second electrical leads in electrical communication with the second electrode. The first planar array and the second planar array of corresponding first and second electrodes may be configured to provide a voltage difference therebetween, and selected electrodes of the first and second electrodes may be energized by the corresponding one or more first and second electrical leads.

[0009] The first pattern may include a plurality of first rows and first columns defining a first direction and a second direction orthogonal to each other, and each of the first electrodes may have a first length measured along the first direction and a first width measured along the second direction. In this arrangement, first electrodes adjacent to each other in the first direction may be spaced apart from each other by a first spacing, and first electrodes adjacent to each other in the second direction may be spaced apart from each other by a second spacing, wherein the first spacing may be equal to the first length plus twice the gap amount, and wherein the second spacing may be equal to the first width plus twice the gap amount.

[0010] The electrostatic pad may further include a third layer of electrically insulating material sandwiched between the first planar array and the second planar array, wherein the third layer may have a third layer thickness, and wherein the gap amount may be approximately ten times the third layer thickness. Optionally, the gap amount may be 0.3 mm. The first spacing and the second spacing may allow a voltage difference greater than 1.3 kV to be applied between the first planar array and the second planar array of corresponding first and second electrodes without arcing between adjacent electrodes of the first and second electrodes.

[0011] The first electrodes or second electrodes diagonally adjacent to each other may be spaced apart from each other by a diagonal spacing less than twice the first spacing or the second spacing. Optionally, the first spacing and the second spacing may be equal to each other, wherein the first electrodes or the second electrodes diagonally adjacent to each other are spaced apart from each other by a diagonal spacing less than twice the first spacing or the second spacing. The gaps between adjacent electrodes in the first electrode and the gaps between adjacent electrodes in the second electrode may be filled with an electrically insulating material.

[0012] The first pattern may include a plurality of first filling cells and a plurality of first empty cells, wherein each of the first electrodes is arranged in a corresponding one of the first filling cells, and the second pattern may include a plurality of second filling cells and a plurality of second empty cells, wherein each of the second electrodes is arranged in a corresponding one of the second filling cells. Each second empty cell may be arranged above a corresponding one of the first filling cells, and each second filling cell may be arranged above a corresponding one of the first empty cells.

[0013] According to another embodiment, a method for electrostatically attaching a sheet of material between an electrostatic pad and the sheet includes: (i) generating an electric field of alternating positive and negative charges induced on corresponding first electrodes and second electrodes arranged on the electrostatic pad in corresponding first and second planar arrays offset from each other; (ii) positioning the electrostatic pad near or in contact with the sheet; (iii) establishing opposite charges on the sheet due to the electric field; and (iv) electrostatically attaching the sheet to the electrostatic pad.

[0014] In this method, the polarity of the opposite charges on the sheet may be opposite to the polarity of the alternating positive and negative charges induced on the respective first and second electrodes.

[0015] According to another embodiment, an electrostatic pad includes: (i) a first layer of first electrodes arranged in a first pattern consisting of first filling cells and first empty cells, wherein each of the first electrodes is arranged in a corresponding one of the first filling cells; (ii) a second layer of second electrodes arranged in a second pattern consisting of second filling cells and second empty cells, wherein each of the second electrodes is arranged in a corresponding one of the second filling cells; and (iii) a third layer of electrically insulating material sandwiched between the first layer and the second layer. Here, the second pattern is the inverse of the first pattern, and the second layer is oriented above the first layer and is substantially parallel to the first layer.

[0016] In this embodiment, the first pattern and the second pattern may be a first checkerboard pattern and a second checkerboard pattern, respectively. Each second empty cell may be arranged above a corresponding one of the first filling cells, and each second filling cell may be arranged above a corresponding one of the first empty cells. The third layer may contact each of the first layer and the second layer, and the third layer may contact the corresponding first edge and second edge of the first electrode and the second electrode.

[0017] The electrostatic pad may also include one or more first electrical leads in electrical communication with the first electrode and one or more second electrical leads in electrical communication with the second electrode. Additionally, the third layer may have a third layer thickness of approximately 25 microns.

[0018] In this arrangement, the first and second layers of the corresponding first and second electrodes can be configured to provide a voltage difference between them. One of the first and second layers can be configured as a positive polarity layer, and the other of the first and second layers can be configured as a negative polarity layer. Selected electrodes of the first and second electrodes can be energized by corresponding one or more first and second electrical leads.

[0019] In this embodiment, the first pattern may include a plurality of first rows and first columns defining mutually orthogonal first and second directions, each of the first electrodes may have a first length measured along the first direction and a first width measured along the second direction, first electrodes adjacent to each other in the first direction may be spaced apart from each other by a first spacing, and first electrodes adjacent to each other in the second direction may be spaced apart from each other by a second spacing, wherein the first spacing is equal to the first length plus twice the gap amount, and wherein the second spacing is equal to the first width plus twice the gap amount. The third layer may have a third layer thickness, and the gap amount may be approximately ten times the third layer thickness. Optionally, the gap amount may be 0.3 mm. The first spacing and the second spacing may allow a voltage difference greater than 1.3 kV to be applied between the first layer and the second layer of the corresponding first and second electrodes without arcing between adjacent electrodes of the first and second electrodes.

[0020] The first electrodes or the second electrodes diagonally adjacent to each other may be spaced apart from each other by a diagonal spacing smaller than twice the first spacing or the second spacing. Alternatively, the first spacing and the second spacing may be equal to each other, wherein the first electrodes or the second electrodes diagonally adjacent to each other are spaced apart from each other by a diagonal spacing smaller than twice the first spacing or the second spacing. The gaps between adjacent electrodes in the first electrode and the gaps between adjacent electrodes in the second electrode may be filled with an electrically insulating material.

[0021] According to another embodiment, an electrostatic pad includes a first layer of first electrodes arranged in a first planar array, a second layer of second electrodes arranged in a second planar array, and a third layer of electrically insulating material sandwiched between the first layer and the second layer. The first planar array has a plurality of first rows and a plurality of first columns defining a plurality of first cells, wherein each of the first electrodes occupies a corresponding one of the first cells, such that the first electrodes are arranged in a first pattern. The second planar array has a plurality of second rows and a plurality of second columns defining a plurality of second cells, wherein each of the second electrodes occupies a corresponding one of the second cells, such that the second electrodes are arranged in a second pattern opposite to the first pattern, wherein the second layer is arranged above the first layer and is substantially parallel to the first layer.

[0022] The first pattern and the second pattern may be a first checkerboard pattern and a second checkerboard pattern, respectively. The first pattern may include a plurality of first filling cells and a plurality of first empty cells, wherein each of the first electrodes is arranged in a corresponding one of the first filling cells, and the second pattern may include a plurality of second filling cells and a plurality of second empty cells, wherein each of the second electrodes is arranged in a corresponding one of the second filling cells. In this arrangement, each second empty cell may be arranged above a corresponding one of the first filling cells, and each second filling cell may be arranged above a corresponding one of the first empty cells.

[0023] The electrostatic pad may also include one or more first electrical leads in electrical communication with the first electrode and one or more second electrical leads in electrical communication with the second electrode.Here, the first and second layers of the respective first and second electrodes may be configured to provide a voltage difference therebetween.

[0024] The first row and the first column may define a first direction and a second direction orthogonal to each other, each of the first electrodes may have a first length measured along the first direction and a first width measured along the second direction, first electrodes adjacent to each other in the first direction may be spaced apart from each other by a first spacing equal to the first length plus twice the gap amount, and first electrodes adjacent to each other in the second direction may be spaced apart from each other by a second spacing equal to the first width plus twice the gap amount. The third layer may have a third layer thickness, and the gap amount may be approximately ten times the third layer thickness. Optionally, the gap amount may be 0.3 mm.

[0025] According to another embodiment, the electrostatic pad includes: (i) a first planar array of first filling cells and first empty cells, the first planar array being arranged in a first pattern, wherein a corresponding first electrode is arranged in each of the first filling cells, thereby defining a first layer of first electrodes; (ii) a second planar array of second filling cells and second empty cells, the second planar array being arranged in a second pattern opposite to the first pattern, wherein a corresponding second electrode is arranged in each of the second filling electrodes, thereby defining a second layer of second electrodes, wherein the second layer is oriented above the first layer and is substantially parallel to the first layer; and (iii) a third layer of electrically insulating material, which is sandwiched between the first layer and the second layer and in contact with them. Here, each second empty cell is arranged above a corresponding one of the first filling cells, and each second filling cell is arranged above a corresponding one of the first empty cells.

[0026] The electrostatic pad may also include one or more first electrical leads in electrical communication with the first electrode and one or more second electrical leads in electrical communication with the second electrode. In this arrangement, the first and second layers of the respective first and second electrodes may be configured to provide a voltage difference between them.

[0027] In this embodiment, the first pattern and the second pattern may be a first checkerboard pattern and a second checkerboard pattern, respectively. The first pattern may include a plurality of first rows and first columns defining mutually orthogonal first and second directions, each of the first electrodes may have a first length measured along the first direction and a first width measured along the second direction, first electrodes adjacent to each other in the first direction may be spaced apart from each other by a first spacing equal to the first length plus twice the gap amount, and first electrodes adjacent to each other in the second direction may be spaced apart from each other by a second spacing equal to the first width plus twice the gap amount. The third layer may have a third layer thickness, and the gap amount may be approximately ten times the thickness of the third layer. Optionally, the gap amount may be 0.3 mm.

[0028] The above features and advantages and other features and advantages of the present teachings as defined in the appended claims are readily apparent from the following detailed description of some of the best modes and other embodiments for carrying out the present teachings when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a schematic side view of an electrostatic mat according to a conventional method.

[0030] Figures 2 to 3 They are Figure 1Schematic perspective and side views of the electrode shown in .

[0031] Figure 4 is a schematic side view of an electrostatic mat according to the present disclosure.

[0032] Figures 5 and 6 They are Figure 4 Schematic perspective and side views of the electrode shown in .

[0033] Figures 7 and 8 are schematic diagrams of corresponding first and second planar arrays of cells.

[0034] Figures 9 and 10 is a schematic diagram of corresponding first chessboard patterns and second chessboard patterns selectively filled with corresponding first electrodes and second electrodes.

[0035] Fig.11 is a schematic diagram of the second checkerboard pattern of the second electrode superimposed on the first checkerboard pattern of the first electrode.

[0036] Fig.12 is a block diagram illustrating various electrical insulating materials.

[0037] Figures 13 to 15 Schematic diagram of various wiring schemes of the first electrode and the second electrode.

[0038] Fig.16 is a schematic side view of a first layer electrode and a second layer electrode, wherein the first layer and the second layer are a positive polarity layer and a negative polarity layer, respectively.

[0039] Fig.17 is a schematic side view of a first layer electrode and a second layer electrode, wherein the first layer and the second layer are a negative polarity layer and a positive polarity layer, respectively.

[0040] Fig.18 is a flow chart of the steps for the electrostatic attachment method. DETAILED DESCRIPTION

[0041] Referring now to the drawings, wherein like reference numerals refer to like parts throughout the several views, various configurations of a multilayer electrostatic mat 20 are shown and described herein.

[0042] Figure 1 shows a schematic side view of an electrostatic pad 10 according to a conventional method, and Figures 2 to 3 They are Figure 1Schematic perspective and side views of the first electrode 12 and the second electrode 14 are shown in FIG. As shown in the figure, the conventional electrostatic pad 10 includes an alternating sequence of first electrodes 12 and second electrodes 14, all of which are arranged in a single row, plane or layer 16. Note that although the layer 16 of the first electrodes 12 and the second electrodes 14 is shown along only one direction or dimension, it is understood that the alternating positive and negative sequence of the first electrodes 12 and the second electrodes 14 can extend in a plane along two orthogonal directions or dimensions.

[0043] The layer 16 of first and second electrodes 12, 14 may have an electrically insulating layer 19 above and below the layer 16, wherein an optional heater 18 (e.g., a positive temperature coefficient or PTC heater) is arranged along a row or plane above the layer 16 of first and second electrodes 12, 14. It should also be noted that although Figure 1 The first and second electrodes 12 and 14 are shown without spacing or other materials between adjacent electrodes of the first and second electrodes 12 and 14, but Figures 2 to 3 Some of the spacings that may be provided between adjacent first electrodes 12 and second electrodes 14 in the layer 16 are shown.

[0044] Although Figures 1 to 3 Not shown, but multiple electrical leads are attached to the individual first and second electrodes 12, 14, where some electrodes (e.g., the first electrode 12) are wired as "positive" electrodes and other electrodes (e.g., the second electrode 14) are wired as "negative" electrodes, and vice versa. Please note here that some electrodes are named "positive" and others are named "negative", which may refer to the actual polarity of the electrodes, such as the "positive" electrode has a potential of +100 volts and the "negative" electrode has a potential of -100 volts; or, this name may refer to the relative potential difference between them, such as the "positive" electrode has a high voltage (e.g., +200 volts) higher than the "negative" electrode (e.g., 0 volts).

[0045] When the first and second electrodes 12, 14 are energized via electrical leads, a voltage difference ΔV is created between adjacent first and second electrodes 12, 14 and across the layer 16 of first and second electrodes 12, 14, thereby generating an electrostatic charge or potential. Then, once this electrostatic potential has been generated, the electrostatic mat 10 can be brought into close proximity or direct contact with one or more sheets of dry carbon fabric, and the sheets of carbon fabric will be attracted to the electrostatic mat 10 due to electrostatic attraction or adhesion. Once the carbon sheets are electrostatically attracted to the electrostatic mat 10, the electrostatic mat 10 can be lifted and moved, and the carbon sheets will remain attached to the electrostatic mat 10, thereby facilitating the pickup and movement of the carbon sheets.

[0046] Compared to the conventional electrostatic mat 10 described above, the electrostatic mat 20 of the present disclosure solves the technical problem of weak electrostatic adhesion strength by separating the positive and negative electrodes into two separate layers or 2D planar arrays, thereby providing significant benefits and technical advantages that are not taught or suggested by the conventional methods described above. These benefits and technical advantages include the use of structural elements and features that provide higher electrostatic adhesion strength than previous methods.

[0047] Figure 4 shows a schematic side view of an electrostatic mat 20 according to the present disclosure, and Figures 5 and 6 They are Figure 4 Schematic perspective view and side view of the first electrode 32 and the second electrode 62 shown in FIG. As shown in the figure, the electrostatic pad 20 includes a first layer 30 of the first electrode 32, a second layer 60 of the second electrode 62 oriented above the first layer 30 and substantially parallel to the first layer 30, and a third layer 78 of an electrically insulating material 94 sandwiched between the first layer 30 and the second layer 60. Note that although in Figures 4 to 6 The first layer 30 of the first electrode 32 and the second layer 60 of the second electrode 62 are shown along only one direction or dimension, but it can be understood that the first electrode 32 and the second electrode 60 can also extend in a plane along two orthogonal directions or dimensions, as described in more detail below.

[0048] In addition to the third layer 78 of electrically insulating material 94 between the first layer 30 and the second layer 60, additional electrically insulating layers 19 may be arranged below the first layer 30 and above the second layer 60, wherein an optional heater 18 (e.g., a PTC heater) is arranged above the second layer 60. Optionally, these additional electrically insulating layers 19 may be made of the same electrically insulating material 94 as the third layer 78. Additionally, gaps 79 between adjacent ones of the first electrodes 32 and between adjacent ones of the second electrodes 62 may be filled with electrically insulating material 94.

[0049] like Figures 4 to 6 As shown, the first electrode 32 and the second electrode 62 are separated into two corresponding first layers 30 and second layers 60, wherein each of the first electrode 32 and the second electrode 62 may optionally have a uniform length L e , Width W e and thickness T e For example, each of the first electrode 32 and the second electrode 62 may be substantially rectangular in shape, wherein the dimensions are: length L e About 20 mm, width W e is about 5 mm, and the thickness T e Any corners in the first electrode 32 and the second electrode 62 may be rounded to minimize or avoid stress concentrations that may be associated with sharp corners. (See, for example, Fig.13 ) is applied to the first electrode 32 and the second electrode 62 in the embodiment of the present invention. Additionally, the third layer 78 may have a third layer thickness T of approximately 25 microns. 78 (Please note that the figures herein are schematic in nature and thus the features and dimensions shown are for illustrative purposes only and are not necessarily drawn to scale.)

[0050] Now go to Figures 7 to 11 , various schematic diagrams of the first planar array 36 and the second planar array 66 illustrating the first cells 42 and the second cells 72 are shown. Each of the first planar array 36 and the second planar array 66 can be considered as a 2D array or grid of the respective first cells 42 and the second cells 72. Note that while only 4x4 arrays or grids are shown in these figures, it is understood that this is for illustration purposes only, and larger arrays or grids may be provided.

[0051] Figure 7 A first planar array 36 is shown having a plurality of first rows 38 and a plurality of first columns 40, the rows and columns intersecting to define a plurality of first cells 42. Similarly, Figure 8 A second planar array 66 is shown having a second plurality of rows 68 and a second plurality of columns 70 that intersect to define a second plurality of cells 72. Each of the first cells 42 and the second cells 72 has a respective unique "grid position" within the respective first planar array 36 or second planar array 66, which grid position may be named by the row and column number of the cell.

[0052] Figures 9 and 10 Schematic diagrams of first electrodes 32 and second electrodes 62 are shown respectively, wherein first electrodes 32 are arranged in selected cells of first cells 42 in a first pattern 33 as a first checkerboard pattern 34, and second electrodes 62 are arranged in selected cells of second cells 72 in a second pattern 63 as a second checkerboard pattern 64. As shown in the figure, first pattern 33 may be a first checkerboard pattern 34 that is an alternating repeating pattern of first filling cells 44 and first empty cells 46, and second pattern 63 may be a second checkerboard pattern 64 that is also an alternating repeating pattern of second filling cells 74 and second empty cells 76. Each of the first electrodes 32 is arranged in a corresponding one of the first filling cells 44, and each of the second electrodes 62 is arranged in a corresponding one of the second filling cells 74, wherein first empty cells 46 and second empty cells 76 do not have any first electrodes 32 or second electrodes 62 arranged therein at all.

[0053] Note, however, that second checkerboard pattern 64 is the inverse of first checkerboard pattern 34. That is, first cell 42 that is a first fill cell 44 at a given grid position in first checkerboard pattern 34 will correspond to second cell 72 that is a second empty cell 76 at a corresponding grid position in second checkerboard pattern 64. Similarly, first cell 42 that is a first empty cell 46 at a given grid position in first checkerboard pattern 34 will correspond to second cell 72 that is a second fill cell 74 at a corresponding grid position in second checkerboard pattern 64. Thus, first electrodes 32 of first layer 30 are arranged in first checkerboard pattern 34 of first fill cells 44 and first empty cells 46, and second electrodes 62 in second layer 60 are arranged in second checkerboard pattern 64 of second fill cells 74 and second empty cells 76, wherein first checkerboard pattern 34 and second checkerboard pattern 64 are inverses of each other.

[0054] Back to Fig. 9 , note that the first checkerboard pattern 34 has an alternating pattern of first filled cells 44 and first empty cells 46, i.e., a first filled cell-first empty cell pattern 48, which repeats in two mutually orthogonal or perpendicular directions; i.e., a left-right direction and an up-down direction. Thus, the first checkerboard pattern 34 defines a mutually orthogonal first direction 50 and a second direction 52, wherein the first filled cell-first empty cell pattern 48 repeats in both the first direction 50 and the second direction 52. Alternatively, Fig. 9 It can be viewed as a first pattern 33 that includes a plurality of first rows 38 and first columns 40 defining a first direction 50 and a second direction 52 .

[0055] Fig.11 A schematic diagram of a second layer 60, a second planar array 66, a second pattern 63, and / or a second checkerboard pattern 64 of a second electrode 62 superimposed on a first layer 30, a first planar array 36, a first pattern 33, and / or a first checkerboard pattern 34 of a first electrode 32 is shown. Here, each second empty cell 76 is arranged above a corresponding one of the first filling cells 44, and each second filling cell 74 is arranged above a corresponding one of the first empty cells 46.

[0056] like Figures 9 to 11As shown in , each of the first electrodes 32 may have a first length L1 measured along the first direction 50 and a first width W1 measured along the second direction 52. Similarly, each of the second electrodes 62 may have a second length L2 measured along the first direction 50 and a second width W2 measured along the second direction 52. In some configurations, the size of the first electrode 32 may be the same as the size of the second electrode 62; that is, L1=L2 and W1=W2. First electrodes 32 adjacent to each other in the first direction 50 may be spaced apart from each other by a first spacing S1 (along the first direction 50), and first electrodes 32 adjacent to each other in the second direction 52 may also be spaced apart from each other by a second spacing S2 (along the second direction 50). (Optionally, as Fig.10 As illustrated in FIG. 5 , the second electrodes 62 adjacent to each other in the first direction 50 may also be spaced apart from each other by a first spacing S1 (along the first direction 50 ), and the second electrodes 62 adjacent to each other in the second direction 52 may be spaced apart from each other by a second spacing S2 (along the second direction 50 ).

[0057] The first spacing S1 may be equal to the first length L1 plus twice the gap amount G, and the second spacing S2 may be equal to the first width W1 plus twice the gap amount G. The gap amount G may be the third layer thickness T 78 The first spacing S1 and the second spacing S2 may be equal to each other. The first spacing S1 and the second spacing S2 may allow a voltage difference ΔV greater than 1.3 kV to be applied between the first layer 30 and the second layer 60 of the respective first electrode 32 and the second electrode 62 without arcing between adjacent electrodes in the first electrode 32 and the second electrode 62.

[0058] Fig.12 A block diagram illustrating various candidate materials for electrically insulating material 94 from which third layer 78 (and optional other electrically insulating layers 19) is made is shown. For example, electrically insulating material 94 may be polyethylene terephthalate (PET) 95, polyacetate 96, polyimide 97, FR-4 98, some other electrically insulating material 99, or any combination of these materials. Third layer 78 may be in contact with each of first layer 30 and second layer 60, and third layer 78 may be in contact with first edge 47 and second edge 77 of first electrode 32 and second electrode 62, respectively.

[0059] Figures 13 to 15 Schematic diagrams of various wiring or circuit trace schemes for the first electrode 32 and the second electrode 62 are shown. The wiring or traces may include one or more first electrical leads 80 in electrical communication with the first electrode 32 and one or more second electrical leads 82 in electrical communication with the second electrode 62.

[0060] exist Fig.13 In the embodiment, each individual first electrode 32 has its own corresponding first electrical lead 80, and each individual second electrode 62 has its own corresponding second electrical lead 82. These first electrical leads 80 and second electrical leads 82 can be operably connected to a controller 92, which is configured to turn each individual first electrode 32 or second electrode 62 on or off according to a control scheme. Please note that the diagonally adjacent first electrodes 32 or second electrodes 62 can be spaced apart from each other by a diagonal spacing S. d In some embodiments, the diagonal spacing S d It may be smaller than twice the first spacing S1 or the second spacing S2.

[0061] exist Fig.14 In the embodiment, the first electrodes 32 in each column are connected together by a common first electrical lead 80 in the column, and the second electrodes 62 in each column are connected together by a common second electrical lead 82 in the column. Fig.13 Compared to the arrangement shown in FIG. 1 , fewer first and second electrical leads 80 , 82 are used, and a controller 92 can be used to activate or deactivate the first and second electrodes 32 , 62 column by column.

[0062] exist Fig.15 In the embodiment, all electrodes in the first electrode 32 are connected together by a single first electrical lead 80, and all electrodes in the second electrode 62 are connected together by a single second electrical lead 82. In this particular arrangement, Figure 13 to Figure 14 Compared to the arrangement shown in FIG. 1 , fewer first electrical leads 80 and second electrical leads 82 are used, and controller 92 can be used to activate or deactivate all electrodes in first electrode 32 and all electrodes in second electrode 62 simultaneously.

[0063] Please note that although Figures 13 to 15 Only one first electrical lead 80 or second electrical lead 82 is shown connected to each first electrode 32 or second electrode 62, but each first electrical lead 80 or second electrical lead 82 may actually include two or more leads, such as a power lead and a ground or neutral lead. Alternatively, one or more ground planes (not shown) may be provided to which each first electrode 32 or second electrode 62 is connected. In addition, please note that although only one electrostatic pad 20 connected to a controller 92 is shown in these figures (for simplicity), multiple electrostatic pads 20 may also be operably connected to a single controller 92, or multiple controllers 92 may be used. Optionally, and depending on the wiring scheme used, selected electrodes of the first electrode 32 and the second electrode 62 may be activated and deactivated (i.e., turned on and off) by the controller 92 to which the first electrode 32 and the second electrode 60 are connected.

[0064] Figure 16 to Figure 17 A schematic side view of the first layer 30 of the first electrode 32 and the second layer 60 of the second electrode 62 is shown, wherein one of the first layer 30 and the second layer 60 may be a positive polarity layer 84 and the other may be a negative polarity layer 88. Fig.16 In the embodiment, the first layer 30 is a positive polarity layer 84, and the first electrode 32 is a positive electrode 86, while the second layer 60 is a negative polarity layer 88, and the second electrode 62 is a negative electrode 90. In contrast, in Fig.17 , the first layer 30 is a negative polarity layer 88 and the first electrode 32 is a negative electrode 90, while the second layer 60 is a positive polarity layer 84 and the second electrode 62 is a positive electrode 86. In these arrangements, the first layer 30 and the second layer 60 of the corresponding first electrode 32 and second electrode 62 can be configured and energized to generate a desired voltage difference ΔV or electrostatic potential therebetween.

[0065] Although first pattern 33 and second pattern 63 are illustrated as first checkerboard pattern 34 and second checkerboard pattern 64 , respectively, in the drawings, it may be noted that first pattern 33 and second pattern 64 may present other patterns besides first checkerboard pattern 34 and second checkerboard pattern 64 .

[0066] Fig.18 A flow chart of steps of a method 100 for electrostatic attachment between an electrostatic mat 20 and a sheet 11 of material is shown. Note that the elements or inputs for each box or step are shown to the left of each box or step, and the results or outputs produced by each box and step are shown to the right of each box and arrangement. At box 110, an electric field of alternating positive charges 89 and negative charges 91 induced on respective first electrodes 32 and second electrodes 62 arranged on the electrostatic mat is generated in respective first planar arrays 36 and second planar arrays 66 offset from each other. For example, a voltage difference ΔV may be applied or provided on the electrostatic mat 20 and between the first electrode 32 and the second electrode 62 to generate an electric field 83 of alternating positive charges 89, negative charges 91. At box 120, the electrostatic mat 20 is located near or in contact with the sheet 11. At box 130, an opposite charge 93 is established on the sheet 11 due to the electric field 83. And at block 140, the sheet 11 is electrostatically attached to the electrostatic pad 20. In the method 100, the polarity of the opposite charges 93 on the sheet 11 can be opposite to the polarity of the alternating positive charges 89 and negative charges 91 induced on the respective first and second electrodes 32, 62.

[0067] As will be appreciated by those skilled in the relevant art, the electrostatic mat 20 of the present disclosure may be presented or arranged in a variety of different configurations and implementations.

[0068] According to one embodiment, the electrostatic pad 20 includes a first planar array 36 of first electrodes 32 arranged in a first pattern 33 and a second planar array 66 of second electrodes 62 arranged in a second pattern 63 different from the first pattern 33, wherein the first planar array 36 and the second planar array 66 are arranged parallel to each other.

[0069] In this embodiment, one of the first planar array 36 and the second planar array 66 may be disposed directly above the other of the first planar array 36 and the second planar array 66. The first electrode 32 may have a first polarity 85, and the second electrode 62 may have a second polarity 87 opposite to the first polarity 85.

[0070] The electrostatic pad 20 may also include a third layer 78 of electrically insulating material 94 sandwiched between the first planar array 36 and the second planar array 66. The third layer 78 may be in contact with each of the first planar array 36 and the second planar array 66 of the respective first electrodes 32 and the second electrode 62, and the third layer 79 may be in contact with the respective first edge 47 and second edge 77 of the first electrode 32 and the second electrode 62. The third layer 78 may have a third layer thickness T of approximately 25 microns. 78 .

[0071] The second pattern 63 may be a reverse of the first pattern 33. Additionally, the first pattern 33 and the second pattern 63 may be the first checkerboard pattern 34 and the second checkerboard pattern 64, respectively.

[0072] The electrostatic pad 20 may also include one or more first electrical leads 80 in electrical communication with the first electrode 32 and one or more second electrical leads 82 in electrical communication with the second electrode 62. The first planar array 36 and the second planar array 66 of the respective first electrodes 32 and the second electrodes 62 may be configured to provide a voltage difference ΔV therebetween, and selected ones of the first electrodes 32 and the second electrodes 62 may be energized by the respective one or more first electrical leads 80 and the second electrical leads 82.

[0073] The first pattern 33 may include a plurality of first rows 38 and first columns 40 defining mutually orthogonal first directions 50 and second directions 52, and each of the first electrodes 32 may have a first length L1 measured along the first direction 50 and a first width W1 measured along the second direction 52. In this arrangement, first electrodes 32 adjacent to each other along the first direction 50 may be spaced apart from each other by a first spacing S1, and first electrodes 32 adjacent to each other along the second direction 52 may be spaced apart from each other by a second spacing S2, wherein the first spacing S1 may be equal to the first length L1 plus twice the gap amount G, and wherein the second spacing S2 may be equal to the first width W1 plus twice the gap amount G.

[0074] The electrostatic pad 20 may further include a third layer 79 of electrically insulating material 94 sandwiched between the first planar array 36 and the second planar array 66, wherein the third layer 79 may have a third layer thickness T 78 , and wherein the gap amount G can be the third layer thickness T 78 The first spacing S1 and the second spacing S2 may allow a voltage difference ΔV greater than 1.3 kV to be applied between the first planar array 36 and the second planar array 66 of the corresponding first electrodes 32 and the second electrodes 62 without arcing between adjacent electrodes in the first electrodes 32 and the second electrodes 62.

[0075] The first electrodes 32 or the second electrodes 62 diagonally adjacent to each other may be spaced apart from each other by a diagonal interval S. d , the diagonal spacing is less than twice the first spacing S1 or the second spacing S2. Optionally, the first spacing S1 and the second spacing S2 may be equal to each other, wherein the diagonally adjacent first electrodes 32 or second electrodes 62 are spaced apart from each other by a diagonal spacing S d , the diagonal spacing is less than twice the first spacing S1 or the second spacing S2. Gaps 79 between adjacent electrodes in the first electrodes 32 (viewed along the first direction 50 and the second direction 52) and between adjacent electrodes in the second electrodes 62 (viewed along the first direction 50 and the second direction 52) may be filled with an electrically insulating material 94.

[0076] The first pattern 33 may include a plurality of first filling cells 44 and a plurality of first empty cells 46, wherein each of the first electrodes 32 is disposed in a corresponding one of the first filling cells 44, and the second pattern 63 may include a plurality of second filling cells 74 and a plurality of second empty cells 76, wherein each of the second electrodes 62 is disposed in a corresponding one of the second filling cells 74. Each second empty cell 76 may be disposed above a corresponding one of the first filling cells 44, and each second filling cell 74 may be disposed above a corresponding one of the second empty cells 46.

[0077] According to another embodiment, a method 100 for electrostatically attaching between an electrostatic pad 20 and a sheet 11 of material includes: (i) at box 110, generating an electric field of alternating positive charges 89 and negative charges 91 induced on corresponding first electrodes 32 and second electrodes 62 arranged on the electrostatic pad in corresponding first planar arrays 36 and second planar arrays 66 offset from each other; (ii) at box 120, positioning the electrostatic pad 20 near or in contact with the sheet 11; (iii) at box 130, establishing opposite charges 93 on the sheet 11 due to the electric field 83; and (iv) at box 140, electrostatically attaching the sheet 11 to the electrostatic pad 20.

[0078] In this method 100 , the polarity of the opposite charges 93 on the sheet 11 may be opposite to the polarity of the alternating positive and negative charges 89 and 91 induced on the respective first and second electrodes 32 , 62 .

[0079] According to another embodiment, the electrostatic pad 20 includes: (i) a first layer 30 of first electrodes 32 arranged in a first pattern 33 of first filling cells 44 and first empty cells 46, wherein each of the first electrodes 32 is arranged in a corresponding one of the first filling cells 44; (ii) a second layer 60 of second electrodes 62 arranged in a second pattern 63 of second filling cells 74 and second empty cells 76, wherein each of the second electrodes 60 is arranged in a corresponding one of the second filling cells 74; and (iii) a third layer 78 of an electrically insulating material 94 sandwiched between the first layer 30 and the second layer 60. Here, the second pattern 63 is the inverse of the first pattern 33, and the second layer 60 is oriented above the first layer 30 and is substantially parallel to the first layer 30.

[0080] In the present embodiment, the first pattern 33 and the second pattern 63 may be respectively the first checkerboard pattern 34 and the second checkerboard pattern 64. Each second empty cell 76 may be arranged above a corresponding one of the first filling cells 44, and each second filling cell 74 may be arranged above a corresponding one of the first empty cells 46. The third layer 78 may contact each of the first layer 30 and the second layer 60, and the third layer 78 may contact the corresponding first edge 47 and the second edge 77 of the first electrode 32 and the second electrode 62.

[0081] The electrostatic pad 20 may also include one or more first electrical leads 80 in electrical communication with the first electrode 32 and one or more second electrical leads 82 in electrical communication with the second electrode 62. Additionally, the third layer 78 may have a third layer thickness T of approximately 25 microns. 78 .

[0082] In this arrangement, the first layer 30 and the second layer 60 of the corresponding first electrode 32 and the second electrode 62 can be configured to provide a voltage difference ΔV therebetween. One of the first layer 30 and the second layer 60 can be configured as a positive polarity layer 84, and the other of the first layer 30 and the second layer 60 can be configured as a negative polarity layer 88. Selected ones of the first electrode 32 and the second electrode 62 can be energized by the corresponding one or more first electrical leads 80 and the second electrical leads 82.

[0083] In this embodiment, the first pattern 33 may include a plurality of first rows 38 and first columns 40 defining a first direction 50 and a second direction 52 that are orthogonal to each other, each of the first electrodes 32 may have a first length L1 measured along the first direction 50 and a first width W1 measured along the second direction 52, first electrodes 32 adjacent to each other in the first direction 50 are spaced apart from each other by a first spacing S1, and first electrodes 32 adjacent to each other in the second direction 52 are spaced apart from each other by a second spacing S2, wherein the first spacing S1 is equal to the first length L1 plus twice the gap amount G, and wherein the second spacing S2 is equal to the first width W1 plus twice the gap amount G. The third layer 78 may have a third layer thickness T 78 , and the gap amount G can be the third layer thickness T 78 The first spacing S1 and the second spacing S2 may allow a voltage difference ΔV greater than 1.3 kV to be applied between the first layer 30 and the second layer 60 of the respective first electrode 32 and the second electrode 62 without arcing between adjacent electrodes in the first electrode 32 and the second electrode 62.

[0084] The first electrodes 32 or the second electrodes 62 diagonally adjacent to each other may be spaced apart from each other by a diagonal interval S. d , the diagonal spacing is less than twice the first spacing S1 or the second spacing S2. Additionally, the first spacing S1 and the second spacing S2 may be equal to each other, wherein the diagonally adjacent first electrodes 32 or second electrodes 62 are spaced apart from each other by a diagonal spacing S d , the diagonal spacing is less than twice the first spacing S1 or the second spacing S2. In addition, the gaps 79 between adjacent electrodes in the first electrodes 32 and between adjacent electrodes in the second electrodes 62 may be filled with an electrically insulating material 94.

[0085] According to another embodiment, the electrostatic pad 20 includes a first layer 30 of first electrodes 32 arranged in a first planar array 36, a second layer 60 of second electrodes 62 arranged in a second planar array 66, and a third layer 78 of electrically insulating material 94 sandwiched between the first layer 30 and the second layer 60. The first planar array 36 has a plurality of first rows 38 and a plurality of first columns 40 defining a plurality of first cells 42, wherein each of the first electrodes 32 occupies a respective one of the first cells 42, such that the first electrodes 32 are arranged in a first pattern 33. The second planar array 66 has a plurality of second rows 68 and a plurality of second columns 70 defining a plurality of second cells 72, wherein each of the second electrodes 62 occupies a respective one of the second cells 72, such that the second electrodes 62 are arranged in a second pattern 63 that is opposite to the first pattern 33, wherein the second layer 60 is arranged above the first layer 30 and substantially parallel to the first layer 30.

[0086] The first pattern 33 and the second pattern 63 may be respectively the first checkerboard pattern 34 and the second checkerboard pattern 64. The first pattern 33 may include a plurality of first filling cells 44 and a plurality of first empty cells 46, wherein each of the first electrodes 32 is arranged in a corresponding one of the first filling cells 44, and the second pattern 63 may include a plurality of second filling cells 74 and a plurality of second empty cells 76, wherein each of the second electrodes 62 is arranged in a corresponding one of the second filling cells 74. In this arrangement, each second empty cell 76 may be arranged above a corresponding one of the first filling cells 44, and each second filling cell 74 may be arranged above a corresponding one of the first empty cells 46.

[0087] Electrostatic pad 20 may also include one or more first electrical leads 80 in electrical communication with first electrode 32 and one or more second electrical leads 82 in electrical communication with second electrode 62. Here, first layer 30 and second layer 60 of respective first electrode 32 and second electrode 62 may be configured to provide a voltage difference ΔV therebetween.

[0088] The first row 38 and the first column 40 may define a first direction 50 and a second direction 52 that are orthogonal to each other, each of the first electrodes 32 may have a first length L1 measured along the first direction 50 and a first width W1 measured along the second direction 52, first electrodes 32 adjacent to each other in the first direction 50 may be spaced apart from each other by a first spacing S1 that is equal to the first length L1 plus twice the gap amount G, and first electrodes 32 adjacent to each other in the second direction 53 may be spaced apart from each other by a second spacing S2 that is equal to the first width W1 plus twice the gap amount G. The third layer 78 may have a third layer thickness T 78 , and the gap amount G can be the third layer thickness T78 Optionally, the gap amount G may be 0.3 mm.

[0089] According to another embodiment, the electrostatic pad 20 includes: (i) a first planar array 36 of first filling cells 44 and first empty cells 46 arranged in a first pattern 33, wherein a corresponding first electrode 32 is arranged in each of the first filling cells 44, thereby defining a first layer 30 of the first electrodes 32; (ii) a second planar array 66 of second filling cells 74 and second empty cells 76 arranged in a second pattern 63 opposite to the first pattern 33, wherein a corresponding second electrode 62 is arranged in each of the second filling cells 74, thereby defining a second layer 60 of the second electrodes 60, wherein the second layer 62 is oriented above the first layer 30 and is substantially parallel to the first layer 30; and (iii) a third layer 78 of an electrically insulating material 94 sandwiched between and in contact with the first layer 30 and the second layer 60. Here, each second empty cell 76 is arranged above a corresponding one of the first filling cells 44, and each second filling cell 74 is arranged above a corresponding one of the first empty cells 46.

[0090] The electrostatic pad 20 may also include one or more first electrical leads 80 in electrical communication with the first electrode 32 and one or more second electrical leads 82 in electrical communication with the second electrode 62. In this arrangement, the first and second layers 30, 60 of the respective first and second electrodes 32, 62 may be configured to provide a voltage difference ΔV therebetween.

[0091] In the present embodiment, the first pattern 33 and the second pattern 63 may be the first checkerboard pattern 34 and the second checkerboard pattern 64, respectively. The first pattern 33 may include a plurality of first rows 38 and first columns 40 defining mutually orthogonal first directions 50 and second directions 52, each of the first electrodes 32 may have a first length L1 measured along the first direction 50 and a first width W1 measured along the second direction 52, first electrodes 32 adjacent to each other in the first direction 50 may be spaced apart from each other by a first spacing S1 equal to the first length L1 plus twice the gap amount G, and first electrodes 32 adjacent to each other in the second direction 54 may be spaced apart from each other by a second spacing S2 equal to the first width W1 plus twice the gap amount G. The third layer 78 may have a third layer thickness T 78 , and the gap amount G can be the third layer thickness T 78 Optionally, the gap amount G may be 0.3 mm.

[0092] The above description is intended to be illustrative and not restrictive. Although the size and type of the material described herein are intended to be illustrative, they are by no means restrictive, but exemplary embodiments. In the following claims, the use of the terms "first", "second", "top", "bottom", etc. is only used as a label, and is not intended to impose numerical or positional requirements on its object. As used herein, an element or step referenced in the singular and beginning with the word "one" should be understood to not exclude a plurality of such elements or steps, unless otherwise explicitly stated. Additionally, "at least one of A and B" and "A and / or B" should be understood as "only A, only B, or both A and B", respectively. In addition, unless explicitly to the contrary, an embodiment of "including" or "having" one or more elements with a specific attribute may include other such elements that do not have the attribute. When broad descriptive adverbs such as "substantially" and "approximately" are used herein to modify adjectives, these adverbs mean "mostly", "mainly", "for most", "to a large extent" and / or "at least 51% to 99% within the possible range of 100%", and do not necessarily mean "perfectly", "completely", "strictly", "all" or "100%". Additionally, the word "close" herein may be used to describe the position of an object or a portion thereof relative to another object or a portion thereof, and / or to describe the positional relationship of two objects or their respective parts relative to each other, and may mean "near", "adjacent", "close to", "near", "at", etc.

[0093] This written description uses examples, including the best mode, to enable those skilled in the art to make and use the devices, systems, and compositions of matter according to the present disclosure, and to perform the methods. The following claims, including their equivalents, define the scope of the present disclosure.

[0094] Examples of the disclosure may be described according to one or more of the following clauses.

[0095] Item 1. An electrostatic pad, comprising: a first planar array of first electrodes, the first planar array being arranged in a first pattern; and a second planar array of second electrodes, the second planar array being arranged in a second pattern different from the first pattern; wherein the first planar array and the second planar array are arranged parallel to each other.

[0096] Clause 2. The electrostatic mat of Clause 1, wherein one of the first planar array and the second planar array is disposed directly above the other of the first planar array and the second planar array.

[0097] Clause 3. The electrostatic mat of clause 1, wherein the first electrode has a first polarity and the second electrode has a second polarity opposite to the first polarity.

[0098] Clause 4. The electrostatic mat of clause 1, further comprising: a third layer of electrically insulating material, the third layer being sandwiched between the first planar array and the second planar array.

[0099] Clause 5. The electrostatic mat of Clause 4, wherein the third layer is in contact with each of the first and second planar arrays of respective first and second electrodes.

[0100] Clause 6. The electrostatic mat of Clause 4, wherein the third layer contacts respective first and second edges of the first and second electrodes.

[0101] Clause 7. The electrostatic mat of Clause 4, wherein the third layer has a third layer thickness of approximately 25 microns.

[0102] Clause 8. The electrostatic mat of Clause 1, wherein the second pattern is the inverse of the first pattern.

[0103] Clause 9. The electrostatic mat of Clause 1, wherein the first pattern and the second pattern are the first checkerboard pattern and the second checkerboard pattern, respectively.

[0104] Clause 10. The electrostatic mat of Clause 1, further comprising: one or more first electrical leads in electrical communication with the first electrode and one or more second electrical leads in electrical communication with the second electrode.

[0105] Clause 11. The electrostatic mat of Clause 10, wherein the first and second planar arrays of respective first and second electrodes are configured to provide a voltage difference therebetween.

[0106] Clause 12. The electrostatic mat of Clause 10, wherein selected ones of the first and second electrodes are energizable through corresponding one or more first and second electrical leads.

[0107] Item 13. An electrostatic pad according to Item 1, wherein: the first pattern includes a plurality of first rows and first columns defining mutually orthogonal first and second directions; each of the first electrodes has a first length measured along the first direction and a first width measured along the second direction; first electrodes adjacent to each other in the first direction are spaced apart from each other by a first spacing, and first electrodes adjacent to each other in the second direction are spaced apart from each other by a second spacing; wherein the first spacing is equal to the first length plus twice the gap amount; and wherein the second spacing is equal to the first width plus twice the gap amount.

[0108] Clause 14. The electrostatic pad of clause 13, further comprising: a third layer of electrically insulating material sandwiched between the first planar array and the second planar array, wherein the third layer has a third layer thickness, and wherein the gap amount is approximately ten times the thickness of the third layer.

[0109] Clause 15. The electrostatic pad of clause 13, wherein the gap amount is 0.3 mm.

[0110] Clause 16. An electrostatic pad according to clause 13, wherein the first spacing and the second spacing allow a voltage difference greater than 1.3 kV to be applied between the first planar array and the second planar array of corresponding first electrodes and second electrodes without generating arcs between adjacent electrodes of the first electrode and the second electrode.

[0111] Item 17. The electrostatic pad according to Item 13, wherein diagonally adjacent first electrodes or second electrodes are spaced apart from each other by a diagonal spacing that is less than twice the first spacing or the second spacing.

[0112] Item 18. The electrostatic pad of Item 13, wherein the first spacing and the second spacing are equal to each other, and wherein diagonally adjacent first electrodes or second electrodes are spaced apart from each other by a diagonal spacing that is less than twice the first spacing or the second spacing.

[0113] Clause 19. The electrostatic pad of Clause 1, wherein gaps between adjacent ones of the first electrodes and gaps between adjacent ones of the second electrodes are filled with an electrically insulating material.

[0114] Item 20. An electrostatic pad according to Item 1, wherein the first pattern includes a plurality of first filling cells and a plurality of first empty cells, wherein each of the first electrodes is arranged in a corresponding one of the first filling cells; the second pattern includes a plurality of second filling cells and a plurality of second empty cells, wherein each of the second electrodes is arranged in a corresponding one of the second filling cells; each second empty cell is arranged above a corresponding one of the first filling cells, and each second filling cell is arranged above a corresponding one of the first empty cells.

[0115] Item 21. A method for electrostatic attachment between an electrostatic pad and a sheet of material, the method comprising: generating an electric field of alternating positive and negative charges induced on corresponding first electrodes and second electrodes arranged on the electrostatic pad in corresponding first and second planar arrays offset from each other; positioning the electrostatic pad near or in contact with the sheet; establishing opposite charges on the sheet due to the electric field; and electrostatically attaching the sheet to the electrostatic pad.

[0116] Clause 22. The method of Clause 21, wherein the polarity of the opposite charges on the sheet is opposite to the polarity of the alternating positive and negative charges induced on the respective first and second electrodes.

[0117] Item 23. An electrostatic pad, comprising: a first layer of a first electrode, the first layer being arranged in a first pattern consisting of first filling cells and first empty cells, wherein each of the first electrodes is arranged in a corresponding one of the first filling cells; a second layer of a second electrode, the second layer being arranged in a second pattern consisting of second filling cells and second empty cells, wherein each of the second electrodes is arranged in a corresponding one of the second filling cells; and a third layer of an electrically insulating material, the third layer being sandwiched between the first layer and the second layer; wherein the second pattern is the inverse of the first pattern, and wherein the second layer is oriented above the first layer and is substantially parallel to the first layer.

[0118] Clause 24. The electrostatic mat of Clause 23, wherein the first pattern and the second pattern are the first checkerboard pattern and the second checkerboard pattern, respectively.

[0119] Clause 25. The electrostatic mat of Clause 23, wherein each second empty cell is disposed above a corresponding one of the first filling cells, and each second filling cell is disposed above a corresponding one of the first empty cells.

[0120] Clause 26. The electrostatic mat of Clause 23, wherein the third layer is in contact with each of the first layer and the second layer.

[0121] Clause 27. The electrostatic mat of Clause 23, further comprising: one or more first electrical leads in electrical communication with the first electrode and one or more second electrical leads in electrical communication with the second electrode.

[0122] Clause 28. The electrostatic mat of Clause 27, wherein the first and second layers of respective first and second electrodes are configured to provide a voltage difference therebetween.

[0123] Clause 29. The electrostatic mat of Clause 27, wherein one of the first layer and the second layer is configured as a positive polarity layer, and the other of the first layer and the second layer is configured as a negative polarity layer.

[0124] Clause 30. The electrostatic mat of Clause 27, wherein selected ones of the first and second electrodes are energizable through corresponding one or more first and second electrical leads.

[0125] Clause 31. The electrostatic mat of Clause 23, wherein the third layer contacts respective first and second edges of the first and second electrodes.

[0126] Item 32. An electrostatic pad according to Item 23, wherein the first pattern includes a plurality of first rows and first columns defining mutually orthogonal first directions; each of the first electrodes has a first length measured along the first direction and a first width measured along the second direction; first electrodes adjacent to each other in the first direction are spaced apart from each other by a first spacing, and first electrodes adjacent to each other in the second direction are spaced apart from each other by a second spacing; wherein the first spacing is equal to the first length plus twice the gap amount; and wherein the second spacing is equal to the first width plus twice the gap amount.

[0127] Clause 33. The electrostatic mat of Clause 32, wherein the third layer has a third layer thickness, and the gap amount is approximately ten times the third layer thickness.

[0128] Clause 34. The electrostatic pad of clause 32, wherein the gap amount is 0.3 mm.

[0129] Clause 35. An electrostatic pad according to clause 32, wherein the first spacing and the second spacing allow a voltage difference greater than 1.3 kV to be applied between the first layer and the second layer of the corresponding first electrode and the second electrode without generating arcs between adjacent electrodes of the first electrode and the second electrode.

[0130] Item 36. The electrostatic pad of Item 32, wherein the first spacing and the second spacing are equal to each other, and wherein diagonally adjacent first electrodes or second electrodes are spaced apart from each other by a diagonal spacing that is less than twice the first spacing or the second spacing.

[0131] Clause 37. The electrostatic pad of Clause 32, wherein diagonally adjacent first electrodes or second electrodes are spaced apart from each other by a diagonal spacing that is less than twice the first spacing or the second spacing.

[0132] Clause 38. The electrostatic pad of Clause 23, wherein the third layer has a third layer thickness of approximately 25 microns.

[0133] Clause 39. The electrostatic pad of Clause 23, wherein gaps between adjacent ones of the first electrodes and gaps between adjacent ones of the second electrodes are filled with an electrically insulating material.

[0134] Item 40. An electrostatic pad, comprising: a first layer of first electrodes, the first layer being arranged in a first planar array, the first planar array having a plurality of first rows and a plurality of first columns defining a plurality of first units, wherein each of the first electrodes occupies a corresponding one of the first units such that the first electrodes are arranged in a first pattern; a second layer of second electrodes, the second layer being arranged in a second planar array, the second planar array having a plurality of second rows and a plurality of second columns defining a plurality of second units, wherein each of the second electrodes occupies a corresponding one of the second units such that the second electrodes are arranged in a second pattern opposite to the first pattern, wherein the second layer is arranged above the first layer and substantially parallel to the first layer; and a third layer of electrically insulating material, the third layer being sandwiched between the first layer and the second layer.

[0135] Clause 41. The electrostatic mat of Clause 40, wherein the first pattern and the second pattern are a first checkerboard pattern and a second checkerboard pattern, respectively.

[0136] Item 42. An electrostatic pad according to Item 40, wherein the first pattern includes a plurality of first filling cells and a plurality of first empty cells, wherein each of the first electrodes is arranged in a corresponding one of the first filling cells; the second pattern includes a plurality of second filling cells and a plurality of second empty cells, wherein each of the second electrodes is arranged in a corresponding one of the second filling cells; and each second empty cell is arranged above a corresponding one of the first filling cells, and each second filling cell is arranged above a corresponding one of the first empty cells.

[0137] Clause 43. The electrostatic mat of Clause 40, further comprising: one or more first electrical leads in electrical communication with the first electrode and one or more second electrical leads in electrical communication with the second electrode.

[0138] Clause 44. The electrostatic pad of Clause 43, wherein the first layer and the second layer of respective first and second electrodes are configured to provide a voltage difference therebetween.

[0139] Item 45. An electrostatic pad according to Item 40, wherein the first row and the first column define a first direction and a second direction that are orthogonal to each other, each of the first electrodes has a first length measured along the first direction and a first width measured along the second direction, first electrodes adjacent to each other in the first direction are spaced apart from each other by a first spacing equal to the first length plus twice the gap amount, and first electrodes adjacent to each other in the second direction are spaced apart from each other by a second spacing equal to the first width plus twice the gap amount.

[0140] Clause 46. The electrostatic mat of Clause 45, wherein the third layer has a third layer thickness, and the gap amount is approximately ten times the third layer thickness.

[0141] Clause 47. The electrostatic pad of clause 45, wherein the gap amount is 0.3 mm.

[0142] Item 48. An electrostatic pad, comprising: a first planar array consisting of first filling cells and first empty cells, the first planar array being arranged in a first pattern, wherein a corresponding first electrode is arranged in each of the first filling cells, thereby defining a first layer of first electrodes; a second planar array consisting of second filling cells and second empty cells, the second planar array being arranged in a second pattern opposite to the first pattern, wherein a corresponding second electrode is arranged in each of the second filling cells, thereby defining a second layer of second electrodes, wherein the second layer is oriented above the first layer and is substantially parallel to the first layer; and a third layer of electrically insulating material, the third layer being sandwiched between the first layer and the second layer and in contact with the first layer and the second layer; wherein each second empty cell is arranged above a corresponding one of the first filling cells, and each second filling cell is arranged above a corresponding one of the first empty cells.

[0143] Clause 49. The electrostatic mat of Clause 48, wherein the first pattern and the second pattern are a first checkerboard pattern and a second checkerboard pattern, respectively.

[0144] Clause 50. The electrostatic mat of Clause 48, further comprising: one or more first electrical leads in electrical communication with the first electrode and one or more second electrical leads in electrical communication with the second electrode.

[0145] Clause 51. The electrostatic mat of Clause 50, wherein the first and second layers of respective first and second electrodes are configured to provide a voltage difference therebetween.

[0146] Item 52. An electrostatic pad according to Item 48, wherein the first pattern includes a plurality of first rows and first columns defining mutually orthogonal first directions, each of the first electrodes having a first length measured along the first direction and a first width measured along the second direction, first electrodes adjacent to each other in the first direction are spaced apart from each other by a first spacing equal to the first length plus twice the gap amount, and first electrodes adjacent to each other in the second direction are spaced apart from each other by a second spacing equal to the first width plus twice the gap amount.

[0147] Clause 53. The electrostatic mat of Clause 52, wherein the third layer has a third layer thickness, and the gap amount is approximately ten times the third layer thickness.

[0148] Clause 54. The electrostatic pad of clause 52, wherein the gap amount is 0.3 mm.

Claims

1. An electrostatic pad, comprising: a first planar array of first electrodes arranged in a first pattern; and a second planar array of second electrodes arranged in a second pattern different from the first pattern; Wherein, the first planar array and the second planar array are arranged parallel to each other.

2. The electrostatic pad according to claim 1, wherein: One of the first planar array and the second planar array is arranged directly above the other of the first planar array and the second planar array.

3. The electrostatic pad according to claim 1, wherein: The first electrode has a first polarity, and the second electrode has a second polarity opposite to the first polarity.

4. The electrostatic pad according to claim 1, further comprising: A third layer of electrically insulating material is sandwiched between the first planar array and the second planar array.

5. The electrostatic pad according to claim 4, wherein: The third layer is in contact with each of the first and second planar arrays of respective first and second electrodes.

6. The electrostatic pad according to claim 4, wherein: The third layer contacts respective first and second edges of the first and second electrodes.

7. A method of electrostatically attaching a sheet of material to an electrostatic mat, the method comprising: generating, in respective first and second planar arrays offset from each other, an electric field of alternating positive and negative charges induced on respective first and second electrodes arranged on the electrostatic pad; placing the electrostatic pad near or in contact with the sheet; establishing opposite charges on said sheet due to said electric field; as well as The sheet was electrostatically attached to the electrostatic pad.

8. An electrostatic mat, comprising: a first layer of first electrodes arranged in a first pattern consisting of first filling cells and first empty cells, wherein each of the first electrodes is arranged in a corresponding one of the first filling cells; a second layer of second electrodes arranged in a second pattern consisting of second filling cells and second empty cells, wherein each of the second electrodes is arranged in a corresponding one of the second filling cells; and a third layer of electrically insulating material, the third layer of electrically insulating material being sandwiched between the first layer and the second layer; wherein the second pattern is the inverse of the first pattern, and wherein the second layer is oriented above the first layer and substantially parallel to the first layer.

9. An electrostatic mat, comprising: a first layer of first electrodes arranged in a first planar array having a plurality of first rows and a plurality of first columns defining a plurality of first cells, wherein each of the first electrodes occupies a respective one of the first cells such that the first electrodes are arranged in a first pattern; a second layer of second electrodes arranged in a second planar array having a plurality of second rows and a plurality of second columns defining a plurality of second cells, wherein each of the second electrodes occupies a respective one of the second cells such that the second electrodes are arranged in a second pattern that is a reversal of the first pattern, wherein the second layer is arranged above and substantially parallel to the first layer; and A third layer of electrically insulating material is sandwiched between the first layer and the second layer.

10. An electrostatic mat, comprising: a first planar array of first filling cells and first empty cells, the first planar array being arranged in a first pattern, wherein a corresponding first electrode is arranged in each of the first filling cells, thereby defining a first layer of first electrodes; a second planar array of second filled cells and second empty cells, the second planar array arranged in a second pattern, the second pattern being the inverse of the first pattern, wherein a respective second electrode is arranged within each of the second filled cells to define a second layer of second electrodes, wherein the second layer is oriented above and substantially parallel to the first layer; and a third layer of electrically insulating material sandwiched between and in contact with the first and second layers; Each of the second empty cells is arranged above a corresponding one of the first filling cells, and each of the second filling cells is arranged above a corresponding one of the first empty cells.

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