Electrical set screw connector system and method

Abstract

An electrical set screw connector system is provided. The system includes a connector body and a drill bit. The connector body has a set screw and a pressure limit for mechanically and electrically securing the conductor cable therein. The pressure limit corresponds to a torque limit applied to the set screw. The drill bit has a torque limiting region separating the body mating portion from the tool mating portion. The body mating portion operatively mates with the set screw and the tool mating portion operatively mates with the tool. A shear fracture occurs in the torque limiting region at a torque limit.

Description

Technical Field

[0001] The present disclosure relates to an electrical set screw connector. More specifically, the present disclosure relates to a system and method for an electrical set screw connector. Background Art

[0002] Electrical connectors are well known in the art of electrical connections. These electrical connectors may include terminal lugs, tabs, ferrules, terminals, and other connection devices located where conductors are secured to a connector body.

[0003] Crimp connectors are designed to form a mechanical and electrical connection between a conductor and a body via a crimp connection. Other connectors may be designed to form a mechanical and electrical connection between a conductor and a body via a welded or soldered connection. Still further connectors may be designed to form a mechanical and electrical connection between a conductor and a body via a set screw.

[0004] Each type of electrical connector presents different challenges to ensure that the resulting electrical and mechanical connections meet known standards. In the example of an electrical set screw connector, the set screw acts as a pressure member to terminate the conductor to the body.

[0005] The consistent and repeatable application of pressure to effectively couple the conductor to the body is a critical component of the electrical transmission process. One way to ensure that the set screw applies the correct pressure is to apply the set screw at a desired torque. Typically, the desired torque is related to the requirements of a listing agency such as Underwriters Laboratories or UL.

[0006] The amount of pressure required varies based on many factors including the size of the conductor, the size of the body, the materials involved, the performance standards governing the application, and other variables.

[0007] Therefore, different solutions have been proposed to address this challenge in the market, with varying degrees of success, ease of use, and cost. For example, some prior art electrical set screw connectors require special tools, which can be expensive and / or difficult to use. Other prior art solutions require a dedicated connector, where the connector itself has a specialized set screw design, which is expensive to manufacture, and the large number of part numbers depending on the different desired torques can be difficult to manage.

[0008]

[0006] Therefore, it has been determined through the present disclosure that there is a need for systems and methods that overcome, mitigate and / or alleviate one or more of the above-identified detrimental effects and other detrimental effects of prior art electrical set screw connectors. Summary of the invention

[0009] An electrical set screw connector system is provided. The system includes a connector body and a drill bit. The connector body has a set screw and a pressure limit for mechanically and electrically securing a conductor cable therein. The pressure limit corresponds to a torque limit applied to the set screw. The drill bit has a torque limiting region separating a body mating portion from a tool mating portion. The body mating portion operatively mates with the set screw, and the tool mating portion operatively mates with the tool. The torque limiting region shears and breaks at the torque limit.

[0010] In some embodiments, alone or together with any one or more of the foregoing and / or following embodiments, the drill bit includes a cross-sectional shape configured to transfer torque from the tool to the set screw.

[0011] In some embodiments, alone or together with any one or more of the foregoing embodiments and / or the following embodiments, the cross-sectional shape is selected from a group consisting of a quadrilateral, a pentagon, a hexagon, and a plum blossom ( Selected from the group of shapes.

[0012] In some embodiments, alone or together with any one or more of the aforementioned embodiments and / or the following embodiments, the system further includes a tool, and the tool has a drill bit fixing device, which fixes the tool mating part of the drill bit so that the torque provided by the tool through the drill bit fixing device is transmitted to the drill bit.

[0013] In some embodiments, either alone or in combination with any one or more of the foregoing and / or later embodiments, the tool is selected from the group consisting of a wrench, a cordless drill, a corded drill, a corded impact driver, a cordless impact driver, a manually operated electric drill, a pneumatic electric drill, and a pneumatic impact driver.

[0014] In some embodiments, alone or together with any one or more of the preceding and / or following embodiments, the drill bit securing device is selected from the group consisting of a keyless chuck, a keyed chuck, and a collet chuck.

[0015] In some embodiments, alone or together with any one or more of the preceding and / or following embodiments, the drill bit securing device is a collet chuck, and the drill bit further includes a collet recess engageable with the collet chuck.

[0016] In some embodiments, alone or in combination with any one or more of the foregoing and / or later embodiments, the connector body and / or set screw are formed of the same or different conductive materials selected from the group consisting of tin, steel, copper, aluminum, silver, gold, and alloys and platings thereof.

[0017] In some embodiments, alone or together with any one or more of the preceding and / or following embodiments, the system further comprises a plurality of drill bits, wherein each drill bit of the plurality of drill bits has a torque limiting region at which shear fracture occurs at a different torque limit.

[0018] In some embodiments, alone or in conjunction with any one or more of the foregoing and / or following embodiments, the torque limiting regions have different dimensional characteristics configured to provide different torque limits.

[0019] In some embodiments, alone or in combination with any one or more of the preceding and / or following embodiments, the drill bit has markings corresponding to the torque limit.

[0020] In some embodiments, alone or together with any one or more of the aforementioned embodiments and / or the following embodiments, the connector body has a second mark corresponding to the torque limit.

[0021] In some embodiments, alone or together with any one or more of the preceding and / or following embodiments, the marking is selected from the group consisting of color, text, pattern, and any combination thereof.

[0022] A method for electrically and mechanically connecting a conductor cable to a connector body is provided. The method includes the following steps: selecting a first combination of a connector body and a conductor cable for a particular application; selecting a second combination of a tool and a drill bit, the drill bit having a torque limit corresponding to the first combination; retaining the drill bit in the tool; inserting the conductor cable into the connector body; operatively engaging the torque limiting drill bit in a set screw of the connector body; and using the tool to apply torque to the set screw until the torque limit is reached, wherein the drill bit shears and breaks at the torque limit.

[0023] In some embodiments, alone or together with any one or more of the preceding and / or following embodiments, the method further includes removing a portion of the drill bit that engages the set screw.

[0024] In some embodiments, alone or together with any one or more of the preceding and / or following embodiments, the method further comprises removing a portion of the drill bit that is engaged with the tool.

[0025] In some embodiments, either alone or in combination with any one or more of the foregoing and / or later embodiments, the tool is selected from the group consisting of a wrench, a cordless drill, a corded drill, a corded impact driver, a cordless impact driver, a manually operated electric drill, a pneumatic electric drill, and a pneumatic impact driver.

[0026] In some embodiments, alone or in combination with any one or more of the foregoing and / or following embodiments, the torque limit corresponds to a desired pressure applied by the set screw to the conductor cable.

[0027] In some embodiments, alone or together with any one or more of the preceding and / or following embodiments, the step of retaining the drill bit in the tool includes retaining the drill bit in a drill bit retaining device selected from the group consisting of a keyless chuck, a keyed chuck, and a collet chuck.

[0028] In some embodiments, alone or together with any one or more of the preceding and / or following embodiments, the method further comprises the step of loosening the set screw and extracting the conductor cable from the connector body.

[0029] Those skilled in the art will appreciate and understand the above-mentioned features and advantages and other features and advantages of the present disclosure from the following detailed description, drawings and appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a perspective view of an exemplary embodiment of an electrical set screw connector system according to the present invention before use;

[0031] Figure 2 yes Figure 1 A perspective view of the connector system during use;

[0032] Figure 3 yes Figure 1 A perspective view of the connector system after use;

[0033] Figure 4 According to the present disclosure, Figure 1 A perspective view of a torque limited drive drill bit for use with a connector system;

[0034] Figure 5 yes Figure 4 A side view of a drill bit;

[0035] Figure 6 yes Figure 4 Schematic diagram of a drill bit configured with different torque settings;

[0036] Figure 7A-7D is used with Figure 1 Exemplary embodiments of different electrical set screw connectors for use with a connector system;

[0037] Figure 8-Figure 9 is a view of an alternative exemplary embodiment of an electrical set screw connector system according to the present disclosure; and

[0038] Fig.10 is a flow chart illustrating an exemplary embodiment of a method according to the present disclosure. DETAILED DESCRIPTION

[0039] With reference to the accompanying drawings, in particular with reference to Figure 1-Figure 3 , an exemplary embodiment of an electrical set screw connector system according to the present disclosure is shown and generally indicated by reference numeral 10. The connector system 10 utilizes a torque applying tool 12, a connector body 14 with a set screw 16, a conductor cable 18, and a torque limiting drill bit 20 in combination.

[0040] In this exemplary embodiment, the connector body 14 is shown as a terminal lug connector by way of example. Of course, it should be appreciated that the system 10 can be used with any connector body 14 having a set screw 16 that forms a mechanical and electrical connection between the connector body and the conductor cable 18, such as, but not limited to, a splice, a ferrule, a terminal, and other connection devices.

[0041] The drill bit 20 is configured to operatively engage the tool 12 and limit the application of torque to the screw 16 by shearing off the body engaging portion 24 and the tool engaging portion 26, respectively, at the torque limiting region 22. The region 22 may be modified so that different drill bits 20 shear off at different torque levels.

[0042] In this manner, the connector system 10 advantageously provides a user with an easy to use system that allows the user to limit the torque applied by the tool 12 to the screw 16 by simply selecting a drill bit 20 having a desired torque limit.

[0043] The connector system 10 provides a solution that separates the shear-breaking function required to limit torque from the tool 12 and the connector body 14, thereby allowing the use of standard or off-the-shelf tools and connector bodies. Conversely, the solution of the connector system 10 solves these problems by providing a frangible drill bit 20 that is configured to shear-break at different torque levels. This allows the installer to ensure that the set screw 16 is applied with the desired torque in an easy and repeatable manner, while matching fragility with the lowest cost component (drill bit).

[0044] Furthermore, the connector system 10 allows the conductor cable 18 to be subsequently removed from the connector body 14 after initial installation by keeping the set screws 16 intact and unmodified. Thus, the connector system 10 allows the connector body 14 to be used again and again without modification and reinstalled again and again with a desired torque.

[0045] The power tool 12 is shown as a cordless drill that includes a drill bit attachment device 28, such as a keyless chuck. Here, the drill bit 20 fits directly to the device 28 in a known manner. Thus, the connector system 10 does not require the installer to have specialized tools, but rather uses common tools that the installer already has and uses.

[0046] The connector body 14 includes a main body 30 having a conductor opening 32 and a threaded hole 34 that threadably receives the set screw 16. The connector body 14, which is formed as a terminal lug connector in the illustrated embodiment, includes a plurality of pads 36 extending from the main body 30, wherein the pads are configured to mate with another connector (not shown) in a known manner.

[0047] The connector body 14 and the set screw 16 can be formed of the same or different conductive materials. For example, the present disclosure contemplates that the connector body 14 and / or the set screw 16 are made of pure, alloyed or plated conductive metal materials, including materials such as but not limited to tin, steel, copper, aluminum, silver, gold, etc.

[0048] The conductor cable 18 is positioned into the connector body 14 through the opening 32. In some embodiments, the conductor cable 18 may include an insulating layer 38 on the conductive portion (not shown). When the insulating layer 38 is present, using the connector system 10 includes first stripping or removing a portion of the insulating layer that will be inserted into the connector body 14.

[0049] Also refer to Figure 4-Figure 6 , the drill bit 20 is described in more detail.

[0050] The drill bit 20 is made of simple raw materials, and its cross-sectional shape can convert the rotational motion of the tool 12 into the rotational motion of the set screw 16. For example, the drill bit 20 can have a certain cross-sectional shape, such as but not limited to a quadrilateral, pentagon, hexagon or plum blossom. shape or other suitable cross-section.

[0051] The drill bit 20 is further configured such that the torque limiting region 22 separates the body engaging portion 24 from the tool engaging portion 26. In this manner, once the torque applied to the drill bit 20 by the tool 12 reaches a predetermined limit, the drill bit shears and breaks, such that the tool engaging portion 26 can no longer apply additional torque to the body engaging portion 24, and thus the body engaging portion can no longer apply additional torque to the set screw 16 or the conductor cable 18.

[0052] The torque limiting portion 22 may be configured to shear fracture at different torque levels by adjusting and changing one or more of the material properties, physical properties, and dimensional properties of the drill bit 20 . Figure 5Different dimensional characteristics of the drill bit 20 are shown. Here, the torque limiting portion 22 is shown as having certain dimensional characteristics, such as, but not limited to, an angular dimension 40, a length dimension 42, a gap dimension 44, an overall diameter 46, and a zone diameter 48. Adjusting one or more of the dimensional characteristics of the drill bit 20 can be used to change the torque limit at which the torque limiting portion 22 shears.

[0053] In embodiments where the drill bit 20 is made from stock of a single cross-sectional shape, the torque limiting portion 22 may be provided by a simple machining step to modify the stock so that shear failure occurs at a desired torque limit.

[0054] It should be appreciated that the drill bit 20 is shown as an example having a body mating portion 24 and a tool mating portion 26 having the same overall diameter 46 and the same hexagonal drill design. Of course, the present disclosure contemplates the use of the connector system 10 with a drill bit 20 having portions 24, 26 that are the same or different from each other in overall diameter 46 and / or external shape.

[0055] In some embodiments, the connector system 10 may include markings defined on the drill bit 20 so that the installer can easily and repeatably select a drill bit with a desired torque limit. Figure 6 , the drill bit 20 may have markings 50a, 50b, 50c in the form of different colors, the different colors relating to different torque limits.

[0056] In other embodiments, the drill bit 20 may have markings 50d, 50e, 50f in the form of text or patterns associated with different torque limits. Preferably, the markings 50d, 50e, 50f in the form of text or patterns are located on the body mating portion 24 so that the markings can be seen when the drill bit 20 is installed in the tool 12. Figure 2 In other embodiments shown, indicia 50d, 50e, 50f in the form of text or graphics are located on the body mating portion 24 at a position where the indicia can be seen when the drill bit 20 is located in the set screw 16.

[0057] In other embodiments, the connector body 14 may include matching markings that ensure that the installer selects the appropriate drill bit 20. Figure 2 As shown, the connector body 14 may include indicia 52 in the form of text, graphics, or color that matches indicia on a desired drill bit 20 .

[0058] It should be appreciated that the connector system 10 is Figure 1-Figure 33 and 4. It is shown in use with a connector body 14 including a body 30 and a gasket 36. Of course, the present disclosure contemplates the use of the connector system 10 with any configuration of a connector body including a body 30 having a conductor opening 32 and a threaded hole that can threadably receive a set screw 16.

[0059] For example, and refer to Figure 7A-7D , shows an alternative exemplary embodiment of a connector body contemplated for use with the connector system 10 of the present disclosure.

[0060] Fig. 7A The embodiment in FIG. 1 shows a connector body 114 having a main body 130 with a single set screw 116, an opening 132, and a gasket 136. Thus, the connector body 114 allows for the connection of a single conductor when used with the connector system 10.

[0061] Figure 7B The embodiment in FIG. 2 shows a connector body 214 having a main body 230 with a pair of set screws 216 / openings 232 and a single gasket 236. Thus, the connector body 214 allows for the connection of two conductors when used with the connector system 10.

[0062] Figure 7C The embodiment in FIG. 1 shows a connector body 314 having a main body 330 with more than two set screws 316 and a single gasket 336 for each opening 332. Here, the connector body 314 is shown as a plug-in configuration. Thus, the connector body 314 allows any desired number of conductors to be connected when used with the connector system 10.

[0063] Fig.7D 4, similar to the connector body 314, the connector body 414 has a body 430 having more than two set screws 416 and a single gasket 436 for each opening 432. Here, the connector body 414 is shown in a stacked configuration. Therefore, the connector body 414 allows any desired number of conductors to be connected when used with the connector system 10.

[0064] It should be recognized that Figure 1-Figure 3 The connector system 10 is shown with the power tool 12 being shown as a cordless drill having a drill bit securing device 28 in the form of a keyless chuck to which the drill bit 20 mates directly.

[0065] Of course, it should be appreciated that the connector system 10 is not limited to use with a cordless drill, but may be used with wrenches, corded drills, cordless or corded impact drivers, manually operated drills, pneumatic drills, pneumatic impact drivers, and the like.

[0066] Furthermore, it should be appreciated that the connector system 10 is not limited to use with a drill bit securing device 28 in the form of a keyless chuck, but may be used with any other common drill bit securing device, such as but not limited to a keyed chuck, a collet chuck, etc. Furthermore, the drill bit securing device 28 may be a socket and / or a drill driver, which allows the system 10 to be used with common hand tools, such as a ratchet wrench.

[0067] For example, and refer to Figure 8-Figure 9 , the connector system 10 is shown for use with a cordless impact driver 112 having a drill bit securing device 128 in the form of a collet chuck. Here, the drill bit 120 is specifically configured with a collet recess 128a that operatively couples with the device 128 in a known manner.

[0068] The drill bit 120 includes a torque limiting region 122 that separates the body engaging portion 124 and the tool engaging portion 126, respectively, in the manner described above. Here, a collet recess 128a is located on the tool engaging portion 126 of the drill bit 120.

[0069] Reference now Fig.10 , a method of using the connector system 10 is shown and generally indicated by reference numeral 60. During the method 60, components for electrical connection are prepared at step 62, while a torque applying device is prepared at step 64.

[0070] The preparation step 62 includes selecting the correct combination of connector body 14 and conductor cable 18 for the particular application in steps 66 , 68 , respectively, and then inserting the conductor cable into the connector body in step 70 .

[0071] The preparation step 64 includes selecting the correct combination of tool 12 and drill bit 20 for the combination of conductor cable 18 and connector body 14 at steps 72 , 74 , respectively, and then retaining the drill bit 20 in the tool 20 at step 76 .

[0072] Once the preparatory steps 62 , 64 are completed, the method 70 continues to step 78 where the set screw 16 and drill bit 20 are operatively coupled to one another and the tool 12 is activated to torque the set screw until the drill bit shears and breaks at region 22 .

[0073] Finally, the body engaging portion 24 of the drill bit 20 is removed from the set screw 16 and the tool engaging portion 26 is removed from the tool 12 at steps 80 and 82 , respectively.

[0074] The method 60 ensures that the set screw 16 applies the desired pressure on the conductor cable 18 using a standard tool 12 and a standard connector body 14 and keeps the set screw unmodified so that the screw can be subsequently loosened and retightened multiple times as needed.

[0075] It should also be noted that the terms "first", "second", "third", "upper", "lower", etc. may be used herein to modify various elements. Unless specifically stated, these modifiers do not imply a spatial, sequential, or hierarchical order to the modified elements.

[0076] Although the present disclosure has been described with reference to one or more exemplary embodiments, it will be appreciated by those skilled in the art that various changes may be made without departing from the scope of the present disclosure, and equivalents may replace elements thereof. In addition, many modifications may be made without departing from the scope of the present disclosure to adapt specific situations or materials to the teachings of the present disclosure. Therefore, it is intended that the present disclosure is not limited to the specific embodiments disclosed as the best mode contemplated, but that the present disclosure will include all embodiments falling within the scope of the appended claims.

[0077] Parts List

[0078] Connector System 10

[0079] Torque applying tool12

[0080] Connector body 14

[0081] Set screw 16

[0082] Conductor cable 18

[0083] Torque limiting drill bit 20

[0084] Torque limit area 22

[0085] Body mating portion 24

[0086] Tool matching part 26

[0087] Drill bit fixing device 28

[0088] Body 30

[0089] Conductor opening 32

[0090] Threaded hole 34

[0091] Pad 36

[0092] Insulation layer 38

[0093] Angle size 40

[0094] Length 42

[0095] Gap size 44

[0096] Total diameter 46

[0097] Area diameter 48

[0098] Color code 50a-50c

[0099] Text / graphic mark 50d-50f

[0100] Matching Tag 52

[0101] Connector body 114

[0102] Main body 130

[0103] Single set screw 116

[0104] Opening 132

[0105] Pad 136

[0106] Connector body 214

[0107] Main body 230

[0108] Set screw 216

[0109] Conductor opening 232

[0110] Pad 236

[0111] Connector body 314

[0112] Main body 330

[0113] Set screw 316

[0114] Conductor opening 332

[0115] Pad 336

[0116] Connector body 414

[0117] Main body 430

[0118] Set screw 416

[0119] Conductor opening 432

[0120] Pad 436

[0121] Impact Driver 112

[0122] Drill bit fixing device 128

[0123] Drill 120

[0124] Collet notch 128a

[0125] Torque limit area 122

[0126] Body mating portion 124

[0127] Tool matching part 126

[0128] Method 60

[0129] Preparation Step 62

[0130] Preparation Step 64

[0131] Connector Selection Step 66

[0132] Cable Selection Step 68

[0133] Insert step 70

[0134] Tool Selection Step 72

[0135] Drill bit selection step 74

[0136] Drill Bit Hold Step 76

[0137] Set Screw Torque Step 78

[0138] Remove steps 80, 82

Claims

1. An electrical set screw connector system, comprising: a connector body having a set screw, the connector body having a pressure limit for mechanically and electrically securing a conductor cable therein, the pressure limit corresponding to a torque limit applied to the set screw; and a drill bit having a torque limiting region separating a body engaging portion configured to operatively engage the set screw from a tool engaging portion configured to operatively engage the tool, Wherein, the torque limiting region undergoes shear fracture under the torque limit.

2. The connector system according to claim 1, wherein: The drill bit includes a cross-sectional shape configured to transfer torque from the tool to the set screw.

3. The connector system according to claim 2, wherein: The cross-sectional shape is selected from a group including quadrilaterals, pentagons, hexagons and Selected from the group of shapes.

4. The connector system of claim 1, further comprising the tool, wherein: The tool includes a drill bit securing device configured to operatively secure a tool mating portion of the drill bit such that a torque provided by the drill bit securing device is transmitted to the drill bit.

5. The connector system of claim 4, wherein: The tool is selected from the group consisting of a wrench, a cordless drill, a corded drill, a corded impact driver, a cordless impact driver, a manually operated drill, a pneumatic drill, and a pneumatic impact driver.

6. The connector system of claim 4, wherein: The drill bit securing device is selected from the group consisting of a keyless chuck, a keyed chuck, a collet chuck, a sleeve, and a drill driver.

7. The connector system of claim 4, wherein: The drill bit securing device is a collet chuck, and wherein the drill bit further comprises a collet recess operatively engageable with the collet chuck.

8. The connector system of claim 1, wherein: The connector body and / or the set screw are formed of the same or different conductive materials, the conductive material being selected from the group consisting of tin, steel, copper, aluminum, silver, gold, and alloys and platings thereof.

9. The connector system of claim 1, wherein: The system further includes a plurality of drill bits, each drill bit of the plurality of drill bits having a torque limiting region at which shear failure occurs at a different torque limit.

10. The connector system of claim 9, wherein: The torque limiting regions have different dimensional characteristics configured to provide different torque limits.

11. The connector system of claim 1, wherein: The drill bit has markings thereon corresponding to the torque limit.

12. The connector system of claim 11, wherein: The connector body has a second mark corresponding to the torque limit.

13. The connector system of claim 11, wherein: The mark is selected from the group consisting of color, text, pattern and any combination thereof.

14. A method for electrically and mechanically connecting a conductor cable to a connector body, the method comprising: selecting a first combination of the connector body and the conductor cable for a particular application; selecting a second combination of a tool and a drill bit, the drill bit having a torque limit corresponding to the first combination; retaining the drill bit in the tool; inserting the conductor cable into the connector body; operatively engaging the torque limiting drill bit into a set screw of the connector body; and The tool is used to apply torque to the set screw until the torque limit is reached, wherein the drill bit shears and breaks at the torque limit.

15. The method of claim 14, further comprising removing a portion of the drill bit that engages the set screw.

16. The method of claim 14, further comprising removing a portion of the drill bit that is engaged with the tool.

17. The method according to claim 14, wherein: The tool is selected from the group consisting of a wrench, a cordless drill, a corded drill, a corded impact driver, a cordless impact driver, a manually operated drill, a pneumatic drill, and a pneumatic impact driver.

18. The method according to claim 14, wherein: The torque limit corresponds to a desired pressure applied to the conductor cable by the set screw.

19. The method according to claim 14, wherein: The step of retaining the drill bit in the tool includes retaining the drill bit in a drill bit securing device selected from the group consisting of a keyless chuck, a keyed chuck, a collet chuck, a socket, and a drill driver.

20. The method of claim 14, further comprising loosening the set screw and extracting the conductor cable from the connector body.

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