TW202341852A - Esd tooling - Google Patents

Abstract

An electrostatic discharge protection tool for reducing electrostatic charge present on a workpiece within a workpiece processing module, with a movable head and in which an at least partially conductive path is formed between the tip of the and the body of the tool, for grounding a charged workpiece in contact with the tip.

Description

Anti-static workwear

The present invention relates to electrostatic discharge protection tools, tooling blocks, printing presses and methods of protecting workpieces from electrostatic discharge.

Industrial screen printers typically apply a pattern of holes in a thin flat layer or mask, such as a stencil (which is a patterned solid material such as stainless steel) or screen (which is a mesh material coated with an emulsion). A conductive printing medium (such as solder paste, silver paste, or conductive ink) is applied to a planar workpiece (such as a circuit board). The present invention applies equally to screen printing and stencil printing, and for convenience, in the remainder of this document the term "stencil" will be used to refer to any such patterned mask. Print media is applied using an angled blade or squeegee while the workpiece is clamped in a fixed printing position. The same machines can also be used to print certain non-conductive media, such as glue or other adhesives, onto the workpiece. After printing is completed, the scraper is lifted from the upper surface of the template, the template is separated from the printing workpiece, and then the printing workpiece is released.

After this printing operation in the press, the printed workpieces can be transferred to other processing modules within the production line. In particular, the printed workpiece can be transferred to an assembly machine, which can attach electrical or electronic components to the workpiece.

To ensure high-quality printing, the workpiece must be supported so that the surface to be printed is parallel to the usually horizontal printing screen. The workpiece support must be able to withstand the pressure exerted on it during the printing operation, in particular withstand the downward pressure exerted by the doctor blade. , while maintaining the correct alignment of the workpiece.

It is also necessary to provide suitable support for the workpiece during the placement operation, although the downward pressure exerted on the workpiece during the placement operation is usually much lower than that exerted during the printing operation.

The simplest type of support is to use a flat surface or platen on which the workpiece can be mounted. However, in many cases this arrangement is not possible, in particular where the underside of the workpiece has been previously printed and equipped with components (e.g. in a previous placement operation) and the printing or placement needs to be done before the printing or placement is applied to the top of the workpiece. Support this bottom surface during installation operations. The presence of components on the underside of the workpiece means that the workpiece will not be flat, and components are also susceptible to damage if they are "squashed" during printing or placement operations. For this purpose, specialized support solutions called "tooling" are used.

There are currently two common tooling options that provide support for printed circuit boards (PCBs) during printing and placement operations: 1) Specialized Tooling Blocks - These are large blocks of material whose upper surface has a three-dimensional profile, e.g. by machining, designed to accommodate the specific PCB mounted on it. The tooling block can be conveniently located on a flat lower support plate or "tooling table". 2) Tooling Pins - These are thin posts positioned to contact the circuit board in use, avoiding contact with any components (or other delicate or critical areas) on the underside. The pins are usually magnetic, i.e. they include permanent magnets or electro-permanent magnets inside them to non-permanently attach the pins to a workbench, which may conveniently be made of a magnetically permeable material such as steel. For example, ASM currently uses simple, low-cost molded plastic tooling pins with a neodymium permanent magnet on the bottom of each pin. In printing presses, tooling pins are typically placed manually on the tooling table (although automated placement systems are beginning to be introduced), while placement machines (such as those produced by ASM) can offer both manual and automated placement options. With manual systems, it is time-consuming and laborious for operators to consistently place pins with the required precision. Automated placement systems can save time and reduce defects by accurately placing pins. Automated placement systems typically use "pin picker" devices that are operable to engage pins from above, where the pins are located on a workbench or in a storage library. The pin picker can then lift the pin, move it laterally to the desired location, and lower it onto the workbench.

An example of such an automated placement system is schematically shown in Figure 1 . The automated placement system uses a "pin picker" 102, a device operable to engage one or more tooling pins 101A, 101B at a time from above, with individual tooling pins 101A, 101B located on the tooling table. on support surface 123 or in storage 110 . Pin picker 102 can move in the vertical or "Z" direction to engage and subsequently lift tooling pins 101A, 101B, and in the orthogonal "X" and "Y" directions to engage and subsequently lift tooling pins 101A, 101B. The tooling pins move laterally to the desired position. The pin picker 102 can then lower the tooling pin onto the support surface 123 of the tooling table, to which the tooling pin is magnetically attracted. As shown, the pin picker 102 is movable in the Z direction relative to the support gantry 120 from which it is suspended, and is movable along the gantry 120 in the X direction. Y-direction movement is provided by moving the gantry 120 in the Y-direction. Although not shown in Figure 1, the gantry 120 may be supported within a processing module such as a printing press or placement machine. The mounting position of the tooling pins 101A, 101B on the support surface 123 is selected manually or automatically based on the workpiece 130 to be subsequently supported. The workpiece 130 shown includes a substrate 131 , such as a plate or a semiconductor wafer, which in this example has a plurality of features on the underside that hinder the support of the workpiece 130 . These special features may include components 132, vias 133, etc., as those skilled in the art will understand. The location and type of tooling pins 101A, 101B mounted on support surface 123 will depend on the location of these special parts. In the example shown, relatively wide tooling pins 101A are used where the space between the specials allows, and relatively thin tooling pins 101B are used where the space between the specials is small.

Typically, once the workpiece is transported to the printing press or placement machine, the tooling is brought into supporting contact with the workpiece located thereon by elevating the tooling, such as by lifting a tooling table, until the tooling is in contact with the workpiece.

Electronic components present on the workpiece during printing or placement operations are susceptible to damage from electrostatic discharge ("ESD"), which can occur if the workpiece becomes charged with static electricity. There are many opportunities for workpieces to become electrified. For example, the risk of becoming electrified has been found to be particularly high during the printing process due to contact and separation between: - scrapers and stencils, - templates and artifacts, and - The workpiece and the clamps that hold it in the printing position.

While tooling can provide ESD protection (for example, tooling pins are often made of dissipative materials to dissipate electrostatic charge build-up), this is not always reliable. For example, there may be imperfect contact between the pin and the workpiece at any stage when the squeegee is not exerting downward force on the stencil above.

The present invention attempts to overcome this problem and provide reliable ESD protection during processing operations such as printing or placement.

According to the invention, this object is achieved by providing a variable height ESD protection element associated with the tooling which ensures contact with the workpiece within a certain distance. In addition, the optimal location of the ESD protection component is determined by analyzing the Gerber profile associated with the workpiece, and the component can be mounted at the determined location.

According to a first aspect of the present invention, an electrostatic discharge protection tool is provided for reducing electrostatic charges existing on workpieces in a workpiece processing module, including: subject; head; a tip located at the distal end of the head, the tip being at least partially electrically conductive; The head is movable relative to the body between an extended position where the tip is at a greatest distance from the body and a retracted position where the tip is at a shortest distance from the body; biasing means for biasing the head into the extended position, and An at least partially conductive path formed between the tip and the body for grounding a live workpiece in contact with the tip.

According to a second aspect of the invention, there is provided a tooling block for supporting a workpiece during machining operations, comprising the electrostatic discharge protection tool of the first aspect.

According to a third aspect of the invention, there is provided a printing press including the electrostatic discharge protection tool of the first aspect.

According to a fourth aspect of the present invention, a method for protecting a workpiece from electrostatic discharge is provided, including the following steps: i) positioning the tooling on the tooling table of the workpiece processing module to support the workpiece during the processing operation, the tooling including the electrostatic discharge protection tool according to the first aspect, ii) transport the workpiece to the processing position located above the tooling, and iii) moving the workpiece and the tooling table together relative to each other so that the tooling is in supporting contact with the workpiece and the tip of the electrostatic discharge protection tool is in contact with the workpiece, thereby grounding the workpiece via an at least partially conductive path.

Other specific aspects and features of the invention are set forth in the claimed patent scope.

An embodiment of the present invention is shown in Figure 2, which schematically shows an electrostatic discharge protection tool 1 assembled in a tooling block 7 in a cross-sectional view. The tooling block 7 is located on a tooling table (not shown) for vertical movement into and out of engagement with the workpiece W above.

In more detail, the electrostatic discharge protection tool 1 includes a head 2 having a tip 3 located at a distal end (ie, top) of the head 2 . The head 2 is connected to the body 4 so as to be movable relative to the body 4 . As shown, the head 2 is movable along the vertical or Z-axis relative to the body 4 which remains stationary relative to the tooling block 7 in use. The head 2 can be positioned relative to the body 4 in an extended position at the maximum distance of the tip 3 from the body 4 (as shown in Figure 2) and in a retracted position (not shown) at the shortest distance of the tip 3 from the body 4. move between. By way of example only, this arrangement may be achieved by providing a cylindrical vertically extending channel (not shown) in the body 4 and positioning the head 2 within the channel for sliding vertical movement in the channel, The sides of the channel limit the lateral movement of the head 2. By at least partially closing the distal end of the channel, for example the lower end of the channel may be completely closed, vertical movement of the head 2 beyond the retracted or extended position can be prevented. However, the upper end of the channel must remain partially open so that part of the head 2 including the tip 3 can pass through. Advantageously, the head 2 may comprise a collar or shoulder portion at its lower end which extends laterally greater than the upper part of the head 2, which collar prevents the head 2 from exiting through the opening at the upper end of the channel. Located within the electrostatic discharge protection tool 1 are biasing means (not shown) for biasing the head 2 into the extended position. The biasing means may, for example, comprise a compression spring or compressible foam material.

The tip 3 is at least partially electrically conductive and may for example be formed of a metallic material. The tip 3 therefore forms part of an at least partially conductive path formed between the tip 3 and the body 4 for grounding the live workpiece W when it comes into contact with the tip 3 . As shown in Figure 2, the body 4 is grounded at the ground connection 6 at the lowest end of the electrostatic discharge protection tool 1 via a resistor 8 chosen to safely allow a rapid discharge if a live workpiece comes into contact with the tip 3. Resistances around 1MΩ have been found to be suitable for many workpieces, although this depends on the specific application. The electrostatic discharge protection tool 1 is located within an opening 9 formed in the tooling block 7 and is electrically isolated from it by an insulating collar 5 or sleeve formed of insulating material. Typically, the tooling block 7 may comprise a large piece of material in which the opening 9 is formed. As can be seen in Figure 2, in the extended position, the tip 3 protrudes beyond the upper surface of the tooling block 7 so that in use the workpiece W will contact the tip 3 before the tooling block 7.

in use: - the tooling block 7 is located on the tooling table (not shown) of the workpiece processing module to support the workpiece W during the machining operation, and the tooling block includes the electrostatic discharge protection tool 1; - The workpiece W, which may have a high electrostatic charge, is transferred to the processing position above the tooling block 7, entering the position shown in Figure 2; - The workpiece W moves together with the workbench, in this case by lifting the workbench. The tip 3 of the electrostatic discharge protection tool is thereby in contact with the workpiece W to ground the workpiece W via an at least partially conductive path. Subsequently, by further raising the tooling table, the head is pushed downwards to the retracted position against the biasing device while maintaining contact with the underside of the workpiece W until the tooling block 7 makes supporting contact with the workpiece W. When the workpiece is fully supported on the tooling block 7, the machining operation can be performed.

It is beneficial for the tip 3 of the ESD protection tool 1 to contact a conductive area on the underside of the workpiece W (eg a conductive pad or track pre-printed onto the workpiece W). Therefore, the method outlined above preferably includes the initial step of positioning the electrostatic discharge protection tool 1 in a horizontal plane such that it is located below the conductive area of the workpiece W. A better way to do this is to analyze the Gerber data associated with the workpiece W, which accurately provides location information of the conductive areas of the workpiece W.

The above-described embodiments provide a robust method for protecting workpiece W from electrostatic discharge. In alternative embodiments, more sophisticated electrostatic discharge protection tools may be provided in which the resistance of the at least partially conductive path varies depending on the distance between the tip and body to optimize the discharge through the tool.

Figures 3A and 3B schematically show cross-sectional views of the electrostatic discharge protection tool 11 in an extended position and a retracted position respectively. The electrostatic discharge protection tool 11 also includes a head 12 with a tip 13 that is relatively movable relative to the body 14 between an extended position shown in Figure 3A and a retracted position shown in Figure 3B. The head 12 is biased into the extended position by biasing means in the form of a compression spring 15 . The body 14 includes a resistor network 16 having a plurality of resistors 17 each having a different resistance value. These resistors are arranged such that when the distance between tip 13 and body 14 is a first distance, the at least partially conductive path includes a first resistor of the plurality of resistors, and when the distance between tip 13 and body 14 When the distance is the second distance, the at least partially conductive path includes a second resistor of the plurality of resistors, as will be described below. The head 12 includes an electrical contact 20 at its lowest extent configured to electrically contact one of the plurality of resistors at any point along its range of travel between the extended and retracted positions. Single resistor 17. In the extended position shown in Figure 3A, the electrical contact 20 is in electrical contact with the first resistor 18, and in the retracted position shown in Figure 3B, the electrical contact 20 is in electrical contact with the second resistor 19. One resistor 18 and the second resistor 19 have different resistances. At an intermediate point along the course between the extended and retracted positions, the electrical contact 20 is in electrical contact with other resistors in the plurality of resistors. The resistor network 16 is connected to ground at ground connection 21 . In this manner, the electrostatic charge discharge on the workpiece in contact with tip 13 can be controlled, thereby providing a slower discharge to the charged workpiece.

Figure 4 schematically illustrates an alternative embodiment electrostatic discharge protection tool 31. In this embodiment, a variable resistor (in this case a digital potentiometer 32 connected to the lower end of the electrostatic discharge protection tool body) is used to vary the resistance of the at least partially conductive path. The digital potentiometer 32 is controlled by a controller 33 (eg, a processor or the like run or controlled by suitable software or hardware). Such a system can be used to provide a 1MΩ to 0Ω transition when the workpiece is clamped to provide a relatively slow discharge and negligible impedance, such as 0Ω, when the workpiece is not clamped to provide a direct ground path to transmit in Any static electricity generated during the printing process.

Figure 5 schematically shows an alternative embodiment electrostatic discharge protection tool 41 in a cross-sectional view in an extended position. In this embodiment, ESD protection is provided by using a dissipative material in an at least partially conductive path, and similar to the embodiment shown in FIGS. 3A and 3B , the resistance of the at least partially conductive path depends on the relationship between the tip and the body. vary the distance between them to optimize the discharge through the tool. The electrostatic discharge protection tool 41 also includes a head 42 with a tip 43 that is relatively movable relative to the body 44 between an extended position as shown and a retracted position (not shown). The head 42 is biased into the extended position by biasing means in the form of a compression spring 45 . The body is retained in an opening in a tooling block (not shown) via an insulating collar 48 . The body 44 includes a variety of dissipative materials 47 , such as dissipative foam materials each having a different electrical resistance, more such as formed as a collar or ring around the path of travel of the head 42 . These dissipative materials are arranged such that when the distance between tip 43 and body 44 is a first distance, the at least partially conductive path includes a first dissipative material of the plurality of dissipative materials, and when the distance between tip 43 and body 44 is When the distance is a second distance, the at least partially conductive path includes a second dissipative material of the plurality of dissipative materials, as will be described below. The head 42 includes an electrical contact 46 at its lowest extent configured to electrically contact a single one of the plurality of dissipative materials at any point along its range of travel between the extended and retracted positions. Dissipative Materials47. In the extended position shown, for example, the electrical contact 46 is in contact with the uppermost dissipative material 47 . Along its course between the extended and retracted positions, electrical contact 46 makes electrical contact with other dissipative materials in the plurality of dissipative materials. In this way, the electrostatic charge discharge on the workpiece in contact with tip 43 can be controlled.

The embodiment shown in Figures 3 to 5 provides different resistances throughout the range of travel. In some advantageous embodiments of the invention, this idea can be extended so that the ESD protection mechanism can shift between conductive and dissipative paths depending on the range of travel of the head between extended and retracted positions.

Figure 6 schematically shows such an embodiment in a cross-sectional view. The electrostatic discharge protection tool 51 is very similar to the electrostatic discharge protection tool 41 of Figure 5 and includes a plurality of dissipative materials 57 each having a different resistance that the electrical contact 56 contacts sequentially throughout its range of travel. Additionally, a low resistance electrically conductive contact 58 is provided near the lowest extent of the travel range, arranged to contact the electrical contact 56 when in the retracted position. Conductive contact 58 is electrically connected to ground connection 59 which is connected to ground

Figures 7 and 8 schematically illustrate alternative embodiments in which the ESD protection mechanism can shift between conductive and dissipative paths depending on the range of travel of the head between extended and retracted positions. Figure 7 schematically shows the electrostatic discharge protection tool 61 in a sectional view in an extended position, while figure 8 shows the electrostatic discharge protection tool 61 in a retracted position. The electrostatic discharge protection tool 61 is again located within the opening of the tooling block 67 . A head 62 having a tip 63 is movably mounted in the body 64 and is biased into the extended position by biasing means in the form of a compression spring 65 . Head 62 includes electrical contacts 66 configured to contact one of a plurality of dissipative materials 68 located within the body as head 62 moves from an extended position to a retracted position, as shown in FIG. 8 . The arrangement of dissipative material 68 and electrical contacts 66 may be similar to that described above, for example with reference to FIGS. 5 and 6 . Head 62 includes a stem 69 depending downwardly from electrical contacts 66 and is electrically conductive like tip 63 such that an electrically conductive path is formed between tip 63 and the lowest portion of stem 69 . The rod 69 is slidably arranged within a hole 71 formed in the bottom of the body 64 . A conductive contact 70 in the form of a leaf spring is provided at the bottom of the opening within the tooling block 67 and is arranged obliquely upward to contact the rod 69 when the head 62 approaches and enters the retracted position, as shown in Figure 8. Conductive contact 70 is grounded, thereby effectively grounding a live workpiece (not shown) that may come into contact with tip 63 .

The above-mentioned embodiments all use electrostatic discharge protection tools embedded in the tooling block. For specific usage, please refer to the first embodiment, that is, - The tooling block is located on the tooling table (not shown) of the workpiece processing module to support the workpiece W during the processing operation, and the tooling block includes electrostatic discharge protection tools; - the workpiece W, which may have a high electrostatic charge, is transported to a processing position located above the tooling block, and - The workpiece W is moved together with the workbench, for example by lifting the workbench. The tip of the electrostatic discharge protection tool is thereby in contact with the workpiece W to ground the workpiece W via an at least partially conductive path. Subsequently, by further lifting the tooling table, push the head downwardly to the retracted position against the biasing device while maintaining contact with the underside of the workpiece W until the tooling block makes supporting contact with the workpiece W. When the workpiece is fully supported on the tooling block, machining operations can be performed.

Additionally, for all of these embodiments, it is beneficial for the tip of the electrostatic discharge protection tool to contact a conductive area on the underside of the workpiece W (such as a conductive pad or conductive track previously printed onto the workpiece W). Therefore, the method outlined above preferably includes the initial step of positioning the electrostatic discharge protection tool in a horizontal plane so that it is located below the conductive area of the workpiece W. A better way to do this is to analyze the Gerber data associated with the workpiece W. The Gerber data accurately provides location information of the conductive areas of the workpiece W.

As mentioned previously, other types of tooling are often used, especially tooling pins are common. The present invention is equally applicable to such systems, and the electrostatic discharge protection tool may include a free-standing column optionally adapted to provide support for the workpiece during machining operations, similar to standard tooling pins. Here, the term "free-standing post" is used to mean an item of elongated form having a main axis along its length which can be mounted on a flat, level surface such that the main axis extends vertically without being supported by that flat level. The item is supported somewhere other than the surface. This electrostatic discharge protection tool is also suitable for placement by smart pin placement systems.

Figure 9 schematically shows an electrostatic discharge protection tool 81 formed as a free-standing column and usable as tooling pins. The electrostatic discharge protection tool 81 includes a head 82 having a tip 83 at its upper end, and the head 82 is relatively movable relative to the main body 84 . A biasing device (not shown) such as a compression spring biases tip 83 away from body 84 into the extended position shown. The top of the body is designated 87. An at least partially conductive path is formed between the tip 83 and the lowermost end of the body 84 which may ground a live workpiece (not shown) in contact with the tip 83 in which an electrostatic discharge protection tool is mounted The workbench 85 of 81 is grounded. Internally, therefore, the electrostatic discharge protection tool 81 may be similar to the electrostatic discharge protection tool 1 shown in FIG. 2 . The electrostatic discharge protection tool 81 includes an engagement device 86 in the body 84, here in the form of a detent. Engagement means 86 are provided to allow engagement with the latches 89 of the pin pickup 88 of the pin placement mechanism.

During use, the head 82 will be pushed toward its retracted position where the tip 83 will be at or slightly above the top of the body 87 . Therefore, the top of body 87 can provide support for the workpiece, similar to standard tooling pins.

In alternative embodiments (not shown), the resistance of the at least partially conductive path may vary depending on the distance between the tip and the body, similar to the previously described electrostatic discharge protection tools 11, 31, 41, 51, 61.

The advantage of this tooling pin arrangement is greater flexibility in placement of the electrostatic discharge protection tool 81 . Advantageously, the electrostatic discharge protection tool 81 is positioned in a horizontal plane so that when in use it is located below the conductive area of the workpiece. A better way to do this is to analyze the Gerber data associated with the workpiece, which provides accurate location information of the conductive areas of the workpiece. The electrostatic discharge protection tool 81 can then advantageously be positioned on the tooling station 85 at the determined location by using the pin picker 88 of the pin placement mechanism (although manual placement by an operator is also possible). Once any other required tooling pins are also mounted, the workpiece can then be transported to a processing location above the mounted tooling pins and ESD protection tool 81 . For example, by lifting the workbench 85, the workpiece and the workbench 85 are moved closer together. The tip of the electrostatic discharge protection tool 81 is thereby brought into contact with the workpiece to ground the workpiece via an at least partially conductive path. Subsequently, by further raising the tooling table 85, the head 82 is pushed downwardly into the retracted position against the biasing means while maintaining contact with the underside of the workpiece until the tooling pins make supporting contact with the workpiece. In this position, the ESD protection tool 81 may also provide support for the workpiece. When the workpiece is fully supported on the tooling pins, machining operations can be performed. After processing, the tooling pins and ESD protection tool 81 can be left in place, repositioned as needed, or returned to storage (not shown) for future use.

The above-described embodiments are exemplary only and other possibilities and alternatives within the scope of the invention will be apparent to a person skilled in the art.

1: Electrostatic discharge protection tools 2:Head 3: tip 4:Subject 5: Insulation collar 6: Ground connection 7: Tooling block 8: Resistor 9: Open your mouth 11: Electrostatic discharge protection tools 12:Head 13: tip 14:Subject 15: Compression spring 16: Resistor network 17: Resistor 18: First resistor 19: Second resistor 20: Electrical contacts 21: Ground connection 31: Electrostatic discharge protection tools 32:Digital potentiometer 33:Controller 41: Electrostatic discharge protection tools 42:Head 43:tip 44:Subject 45:Compression spring 46: Electrical contacts 47:Dissipative Materials 48:Insulation collar 51: Electrostatic discharge protection tools 56: Electrical contacts 57:Dissipative Materials 58:Conductive contacts 59:Ground connection 61: Electrostatic discharge protection tools 62:Head 63: tip 64:Subject 65:Compression spring 66: Electrical contacts 67: Tooling block 68:Dissipative Materials 69: Rod 70:Conductive contacts 71:hole 81: Electrostatic discharge protection tools 82:Head 83: Tip 84:Subject 85:Workbench 86:Joining device 87: Top of the body 88: Pin Picker 89:Latch 101A: Tooling pin 101B: Tooling pins 102: Pin Picker 110:Repository 120:Bench 130:Artifact 131:Substrate 132:Component 133: Via hole W: workpiece

The invention will now be described with reference to the accompanying drawings (not to scale) in which: Figure 1 schematically shows a known automatic placement system in a cross-sectional view; Figure 2 schematically illustrates in cross-section an embodiment of the present invention, including an electrostatic discharge protection tool assembled within a tooling block; 3A and 3B schematically illustrate the electrostatic discharge protection tool in a cross-sectional view in an extended position and a retracted position respectively; Figure 4 schematically shows an electrostatic discharge protection tool incorporating a digital potentiometer; Figure 5 schematically shows an alternative embodiment of an electrostatic discharge protection tool in a cross-sectional view; Figure 6 schematically shows another alternative embodiment of an electrostatic discharge protection tool in a cross-sectional view; Figures 7 and 8 schematically illustrate in cross-section an alternative embodiment in an extended position and a retracted position respectively; and Figure 9 schematically shows an electrostatic discharge protection tool formed as a free-standing column in a cross-sectional view.

1: Electrostatic discharge protection tools

2:Head

3: tip

4:Subject

5: Insulation collar

6: Ground connection

7: Tooling block

8: Resistor

9: Open your mouth

Claims (20)

An electrostatic discharge protection tool used to reduce the electrostatic charge existing on the workpiece in the workpiece processing module, including: subject; head; a tip located at a distal end of the head, the tip being at least partially electrically conductive; The head is movable relative to the body between an extended position where the tip is at a greatest distance from the body and a retracted position where the tip is at a shortest distance from the body; biasing means for biasing said head into said extended position; and An at least partially electrically conductive path formed between the tip and the body for grounding a live workpiece in contact with the tip. The electrostatic discharge protection tool of claim 1, wherein the resistance of the at least partially conductive path changes according to the distance between the tip and the body. The electrostatic discharge protection tool as described in item 2 of the patent application scope includes a resistor network, the resistor network has a plurality of resistors with different resistance values, and the resistor network is arranged such that when the The at least partially conductive path includes a first resistor of the plurality of resistors when the distance between the tip and the body is a first distance, and when the distance between the tip and the body is At a second distance, the at least partially conductive path includes a second resistor of the plurality of resistors. The electrostatic discharge protection tool as described in claim 2 of the patent application, wherein the at least partially conductive path includes a variable resistor, optionally including an electronically controlled potentiometer. The electrostatic discharge protection tool as described in item 2 of the patent application includes a plurality of dissipative materials with different resistances, and the plurality of dissipative materials are arranged such that when the distance between the tip and the body is a first distance when the at least partially conductive path includes a first dissipative material of the plurality of dissipative materials, and when the distance between the tip and the body is a second distance, the at least partially conductive path A second dissipative material of the plurality of dissipative materials is included. An electrostatic discharge protection tool as claimed in claim 1, including conductive contacts arranged to form part of the at least partially conductive path when the head is in the retracted position, But the head does not form part of the at least partially conductive path when in the extended position. The electrostatic discharge protection tool of claim 1 includes a free-standing column optionally adapted to provide support for the workpiece during machining operations. The electrostatic discharge protection tool described in item 7 of the patent application includes a bonding device, and the bonding device is used to bond with the pin placement mechanism of the workpiece processing module. A workpiece block for supporting a workpiece during machining operations includes an electrostatic discharge protection tool as described in any one of items 1 to 6 of the patent application. The tool block described in claim 9 of the patent application includes a large piece of material, and the electrostatic discharge protection tool is located in an opening formed in the large piece of material. The tooling block of claim 10 includes dissipative material disposed between the tip and the tooling block such that the at least partially conductive path is arranged to be connected to ground via the bulk material. A printing press includes an electrostatic discharge protection tool as described in any one of items 1 to 8 of the patent application scope. The printing press described in Item 12 of the patent application includes a tooling platform for supporting tooling thereon, and the electrostatic discharge protection tool is located on the tooling platform. A method of protecting workpieces from electrostatic discharge consisting of the following steps: i) positioning tooling on a tooling table of a workpiece processing module to support said workpiece during processing operations, said tooling including an electrostatic discharge protection tool as described in any one of claims 1 to 8, ii) transporting said workpiece to a processing position located above said tooling, and iii) moving the workpiece and the tooling table together relative to each other such that the tooling is in supporting contact with the workpiece and the tip of the ESD protection tool is in contact with the workpiece via the at least partially conductive path Ground the workpiece. The method of claim 14 includes the initial step of positioning the electrostatic discharge protection tool so that it is below a conductive area of the workpiece. The method described in claim 15 of the patent application, wherein the step of determining the location includes analyzing Gerber data associated with the workpiece. For the method described in Item 14 of the patent application, the tooling includes a tooling block. For the method described in item 14 of the patent application, the tooling includes a plurality of tooling pins. The method as described in item 18 of the patent application, wherein step i) includes using the pin mounting mechanism of the processing module to move the tooling pins and the electrostatic discharge protection tool. For the method described in item 14 of the patent application, the processing module includes a printing press.

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