The present disclosure relates generally to the electrostatic discharge of a workpiece, and more particularly to, example methods and devices for creating electrical conductivity between a workpiece (e.g., ladder) and a conductive ground that the workpiece is positioned on such that any electrostatic charge built up within the workpiece may discharge into the ground.
Ladders and other types of workpieces are typically made out of light-weight materials (e.g., aluminum, metal) capable of maintaining structure while supporting the weight of a user or the user's items. The strength and weight of the materials can enable a workpiece to be moved easily while also provide structure and support during use. Many of these materials, however, are also electrical conductors that allow the flow of electrostatic charge within portions of the workpiece.
When exposed to some source of electricity, an electrostatic charge can build up within the conducting materials of a workpiece. For instance, when a user pushes a ladder in an area with electrostatic control requirements, the ladder may build up electrostatic charge within the steps and other metal or aluminum portions of the ladder. Although a fully conducting workpiece (e.g., a full metal ladder) would allow for any built up electrostatic charge to flow from the workpiece into the ground, most workpieces often include non-slip pads (e.g., rubber feet) that are included to prevent unwanted movement during use. Since the non-slip pads are usually rubber or other non-conducting materials that create friction between the workpiece and the ground, the pads can block the electrostatic charge from discharging into the ground resulting in potential risks to users and electrostatic-sensitive items.
Therefore, there is a need to create electrical conductivity from a workpiece to the ground to allow electrostatic charge to discharge from the workpiece. One such technique often used can involve discharging electrostatic charge from a workpiece through a grounding wire that connects conducting materials of the workpiece to the ground. Using a grounding wire, however, limits the mobility of the workpiece and can sometimes fail to adequately ground the workpiece. Thus, what are needed are techniques that safely discharge electrostatic charge from a workpiece without limiting the mobility and use of the workpiece.
In one example, a device is described comprising a housing structure configured with an inner portion that extends partially into an outer portion. Particularly, the inner portion and outer portion move relative to each other. The device also includes an elongate rod positioned inside the housing structure. A first end of the elongate rod extends through a top of the housing structure and a second end of the elongate rod extends through a bottom of the housing structure. The device also includes a compressible spring positioned within the housing structure. The spring is partially compressed between the top of the housing structure and the bottom of the housing structure such that a first end of the spring presses against an inner surface of the outer portion of the housing structure and a second end of the spring presses against an inner surface of the inner portion of the housing structure. The device also includes a ground component coupled to the second end of the elongate rod, and an attachment component coupled to the outer portion of the housing structure. The attachment component is configurable for coupling the device to a workpiece such that the ground component presses against a ground surface when the workpiece is positioned on the ground surface and is in use.
In another example, a system is described comprising a workpiece and a device configurable to couple to the workpiece. The device comprises a housing structure configured with an inner portion that extends partially into an outer portion. The inner portion and outer portion move relative to each other. The device also includes an elongate rod positioned inside the housing structure. A first end of the elongate rod extends through a top of the housing structure and a second end of the elongate rod extends through a bottom of the housing structure. The device also includes a cover component coupled to the first end of the elongate rod, and a lock coupled to the elongate rod. The lock is positioned outside the housing structure. The device also includes a compressible spring positioned within the housing structure. The spring is partially compressed between the top of the housing structure and the bottom of the housing structure such that a first end of the spring presses against an inner surface of the outer portion of the housing structure and a second end of the spring presses against an inner surface of the inner portion of the housing structure. The device also includes a ground component coupled to the second end of the elongate rod, and an attachment component coupled to the outer portion of the housing structure. The attachment component is for coupling the device to the workpiece such that the ground component presses against a ground surface when the workpiece is positioned on the ground surface and is in use.
In another example, a method is described. The method includes coupling, via an attachment component of a device, a housing structure of the device to a workpiece such that a ground component of the device presses against a ground surface when the workpiece is positioned on the ground surface and is in use. The housing structure includes an inner portion that extends partially into an outer portion, and the inner portion and the outer portion move relative to each other. The method also includes responsive to an application of downward force on the workpiece, compressing a compressible spring positioned within the housing structure of the device. The spring is partially compressed between the top of the housing structure and the bottom of the housing structure such that a first end of the spring presses against an inner surface of the outer portion of the housing structure and a second end of the spring presses against an inner surface of the inner portion of the housing structure. The method also includes responsive to compressing the compressible spring, causing the ground component of the device to extend toward the ground surface.
The features, functions, and advantages that have been discussed can be achieved independently in various examples or may be combined in yet other examples further details of which can be seen with reference to the following description and drawings.
The novel features believed characteristic of the illustrative examples are set forth in the appended claims. The illustrative examples, however, as well as a preferred mode of use, further objectives and descriptions thereof, will best be understood by reference to the following detailed description of an illustrative example of the present disclosure when read in conjunction with the accompanying drawings, wherein:
Disclosed examples will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all of the disclosed examples are shown. Indeed, several different examples may be described and should not be construed as limited to the examples set forth herein. Rather, these examples are described so that this disclosure will be thorough and complete and will fully convey the scope of the disclosure to those skilled in the art.
Example implementations describe methods and devices for electrostatic discharge of a workpiece. Particularly, examples involve establishing electrical conductivity between a workpiece and the ground surface that the workpiece is positioned upon when the workpiece is in use. The connection can enable electrostatic charge that built up within the workpiece to discharge into the ground.
Example implementations also aim to permit a user to easily move a workpiece when the workpiece is not in use. Unlike a ground wire that limits the mobility of the workpiece to the length of the ground wire, an example implementation involves coupling one or more devices to a workpiece in a manner that enables any electric charge built up within the workpiece to flow through at least one of the devices into the ground. Each device can be used to establish electrical conductivity between the workpiece and the ground, such as when the workpiece is in use. As a result, a user can safely use the workpiece during electrical work without the risk of potential electrical shocks and also have the ability to move the workpiece to different locations between uses.
Referring now to the Figures,
Components of the device 100 may include one or more conductive materials capable of conducting electricity to enable electrostatic charges to discharge from conductive materials of a workpiece (e.g., workpiece 132) into a conductive ground surface (e.g., ground surface 134). For instance, in some example implementations, all or a subset of components of the device 100 may be made out of aluminum, metal, or other materials with the ability to conduct electrostatic charges.
The device 100 includes the housing structure 102 to protect components (e.g., the elongate rod 108, the compressible spring 122). In the example implementation, the housing structure 102 is configured with an inner portion 104 that extends partially into an outer portion 106. As shown, the inner portion 104 and the outer portion 106 move relative to each other. For instance, the inner portion 104 and the outer portion 106 can be physically separate components of the housing structure 102 with the diameter of the outer portion 106 greater than the diameter of the inner portion 104. For example, the outer portion 106 can have a diameter that is greater than the diameter of the inner portion 104 by at least a thickness of the walls of the housing structure 102.
Additionally, the housing structure 102 can have various configurations within examples, such as a circular or octagonal configuration. In another example implementation shown in
Inside the housing structure 102, the elongate rod 108 is positioned such that a first end 110 of the elongate rod 108 extends through a top of the housing structure 102 via a slot 114 in the outer portion 106 of the housing structure 102. In addition, the second end 112 of the elongate rod 108 extends through a bottom of the housing structure 102 via a slot 116 in the inner portion 104 of the housing structure 102. As shown in
The cover component 118 is coupled to the first end 110 of the elongate rod 108. Particularly, the cover component 118 is positioned proximate the slot 114 of the outer portion 106 of the housing structure 102. As such, the cover component 118 may hold the elongate rod 108 in place relative to the outer portion 106 of the housing structure 102. In the example implementation shown in
Additionally, in a further example, the device 100 may not include the cover component 118. Rather, the first end 110 of the elongate rod 108 may have a greater diameter than the slot 114 of the outer portion 106 of the housing structure 102. At such a diameter, the first end 110 can press against the top of the housing structure 102 and hold the rest of the elongate rod 108 fixed within the housing structure 102 in a manner similar to the cover component 118.
The lock 120 is coupled to the elongate rod 108 proximate the slot 116 of the inner portion 104 of the housing structure 102. The lock 120 is positioned outside the housing structure 102 such that the lock 120 can prevent the inner portion 104 of the housing structure 102 from slipping down toward the ground component 128. In the example implementation shown in
In a further example, the device 100 might not include the lock 120. Rather, the ground component 128 may couple to the elongate rod 108 proximate the bottom of the housing structure 102 proximate the slot 116 in the inner portion 104 of the housing structure 102.
The compressible spring 122 is positioned within the housing structure 102. In some examples, the compressible spring 122 is positioned around the elongate rod 108. In other examples, the compressible spring 122 may have other positions (e.g., next to the elongate rod 108).
As shown in
In some examples, the compressible spring 122 is positioned around and unattached to the elongate rod 108 (i.e., floating around the elongate rod 108) within the housing structure 102. The compressible spring 122 is floating around the elongate rod 108 when no portion of the compressible spring 122 is attached to the elongate rod 108. Rather, the elongate rod 108 simply extends through the center of the compressible spring 122.
The ground component 128 of the device 100 is coupled to the second end 112 of the elongate rod 108. When the workpiece 132 is positioned on the ground surface 134 and is in use, the device 100 can allow any electrostatic charges in the workpiece 132 to discharge through the device 100 into the ground surface 134 via the ground component 128. The ground component 128 can be made out of metal or other conductive materials that allow for electrostatic charges to discharge from conductive materials of the workpiece 132 into the conductive ground surface 134.
The attachment component 130 is coupled to the outer portion 106 of the housing structure 102. Particularly, the attachment component 130 is configurable for coupling the device 100 to a conductive portion of the workpiece 132 such that the ground component 128 presses against a ground surface 134 when the workpiece 132 is positioned on the ground surface 134 and is in use. Electrostatic charge from the conductive portion of the workpiece 132 can flow into the device 100 through the attachment component 130 or another component of the device 100 and then further flow through the device 100 into the conductive ground surface 134 via the ground component 128. In some examples, the attachment component 130 can include a clamping element that enables the device 100 to couple to a portion of the workpiece 132. The attachment component 130 can also have other configurations configurable to attach the device 100 to the workpiece 132.
The workpiece 132 is shown in
In addition, an attachment component 140 shown in
In addition, when the workpiece is in use, the devices 100 configured with wheels 138 can still discharge electrostatic charges within the workpiece as a result of a downward force applied to the workpiece even when the workpiece also includes rubber non-slip pads that prevent unwanted movements. In particular, when the workpiece is configured for use, the wheels 138 can maintain contact within the ground enabling electrostatic charge to discharge from the workpiece while bottom portions (e.g., non-slip pads) of the workpiece maintain the position and balance of the workpiece. The compression spring 122 within the device 100 can compress to allow the wheels 138 to shift upward to enable the bottom portions of the workpiece to engage the ground surface while also keeping the wheels 138 in contact with the ground surface as well. In a further example, the wheels 138 can include a locking mechanism to prevent the wheels 138 from rotating during use of the workpiece.
Method 142 may include one or more operations, functions, or actions as illustrated by one or more of blocks 144, 146, and 148. Although the blocks are illustrated in a sequential order, these blocks may also be performed in parallel, and/or in a different order than those described herein. Also, the various blocks may be combined into fewer blocks, divided into additional blocks, and/or removed based upon the desired implementation.
At block 144, the method 142 involves coupling, via the attachment component 130 of the device 100, the housing structure 102 of the device 100 to a workpiece (e.g., workpiece 132) such that the ground component 128 presses against a ground surface (e.g., ground surface 134) when the workpiece 132 is positioned on the ground surface 134 and is in use.
At block 146, the method 142 involves compressing the compressible spring 122 positioned within the housing structure 102 of the device 100 responsive to an application of downward force on the workpiece 132.
For instance, the application of downward force can result from additional weight on the workpiece 132 that occurs when a user climbs upon a portion of the workpiece 132. The downward force can cause the outer portion 106 of the housing structure 102 remain stationary relative to the workpiece 132 while also causing the elongate rod 108 to shift downward pushing the ground component 128 against the ground surface 134. During the application of the downward force, the ground surface 134 limits the amount that the ground component 128 and elongate rod 108 can extend forward resulting in further compression of the spring 122 inside the housing structure 102. The additional compression of the spring 122 permits the inner portion 104 of the housing structure 102 to further extend into the outer portion 106 of the housing structure 102 by an amount that proportionate to an amount of additional compression of the spring 122.
At block 148, the method 142 involves causing the ground component 128 of the device 100 to extend toward the ground surface responsive to compressing the compressible spring 122. As indicated above, the application of a downward force on the workpiece causes further compression of the compressible spring 122 and also causes the ground component 128 to press against the ground surface 134 shared by the workpiece 132. When the ground component 128 is firmly pressed against the ground surface 134, electrostatic charge built up within the workpiece 132 can discharge through the device 100 into the conductive ground surface 134 via the ground component 128. Electrostatic charge can also discharge from a workpiece via a device configured with a conductive wheel 138 in a similar manner within examples.
By the term “substantially” or “about” used herein, it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.
The description of the different advantageous arrangements has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the examples in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art. Further, different advantageous examples may describe different advantages as compared to other advantageous examples. The example or examples selected are chosen and described in order to best explain the principles of the examples, the practical application, and to enable others of ordinary skill in the art to understand the disclosure for various examples with various modifications as are suited to the particular use contemplated.
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