Wrench engagement profile

Abstract

A tool for driving a fastener may include: a box end configurable to engage with the fastener; and a lever arm operably coupleable to the bin end and extendable away from the bin end. The box end may be engaged with the fastener through the engagement hole. The engagement hole may include a plurality of instances of gripping surfaces extending parallel to respective planar surfaces of the fastener to operably connect the engagement hole and the fastener such that the fastener may be driven while avoiding contact with corner portions of the fastener disposed at intersections of the planar surfaces. Multiple instances of the clamping surface may extend from a starting point to a clamping point disposed between about 50% and about 85% of the distance between successive corner portions along each of the flat surfaces.

Description

Technical Field

[0001] Exemplary embodiments generally relate to hand tools, and more specifically to improvements of a tool configured to remove or drive a fastening nut or other drivable component in either direction. Background Technology

[0002] A wrench is a common tool used to tighten and loosen nuts, bolts, and other drivable parts or fasteners. A common form of wrench is the combination wrench, which may include an open-end, a lever arm, and a box end. The open-end and box ends can each be attached to a nut, bolt head, or other fastener. Because high torque is typically applied with these tools, and high strength and durability are expected, wrenches are traditionally made of metals such as iron or steel.

[0003] Wrenches are typically manufactured in sets, including a range of sizes to correspond to every common fastener size. Often, the dimensions of both the open and closed ends of the wrench are designed for fasteners of the same size, allowing the entire wrench to correspond to a single fastener size. Thus, wrenches can be available for each common fastener size to drive the fastener in either tightening or loosening direction. In this regard, the shape of either end of the wrench can match the head of the fastener nut or fastener (e.g., typically hexagonal) to ensure maximum surface contact and thus ensure that force is evenly distributed across all faces of the fastener nut or fastener head. However, it is common for the force from the wrench to concentrate at the corners of the fastener nut (i.e., the transition between adjacent faces forming the common hexagonal shape). These concentrated forces can damage or strip away the corners of the fastener nut or fastener head, causing the corners to become rounded. When the corners become sufficiently rounded, a conventional wrench will slip when large forces are applied, or the wrench may even become useless and no longer be able to adequately clamp the fastener for movement in one or both directions. The risk of rounding may be increased when fasteners are exposed to water, harsh chemicals, or other environments that may rust or corrode the fastener nut or head.

[0004] Therefore, it may be desirable to provide a new design for a wrench with improved performance, including the ability to clamp and drive fasteners in both directions, including severely rounded, corroded, or damaged fasteners. Summary of the Invention

[0005] Some exemplary embodiments may provide a tool for driving a fastener, which may include: a housing end configured to engage a fastener; and a lever arm operably coupled to the housing end and extending away from the housing end. The housing end engages the fastener via an engagement hole. The engagement hole may include multiple instances of clamping surfaces extending parallel to respective flat surfaces of the fastener to operably connect the engagement hole and the fastener, such that the fastener can be driven while avoiding contact with corner portions of the fastener located at intersections of the flat surfaces. The multiple instances of the clamping surfaces may extend from a starting point to a clamping point located between approximately 50% and approximately 85% of the distance between successive corner portions along each of the flat surfaces.

[0006] In another exemplary embodiment, an engagement hole may be provided for engaging and driving a fastener with a tool. The engagement hole may include multiple instances of clamping surfaces extending parallel to respective flat surfaces of the fastener to operatively connect the engagement hole and the fastener, such that the fastener can be driven while avoiding contact with corner portions of the fastener located at intersections of the flat surfaces. The multiple instances of the clamping surfaces may extend from a starting point to a clamping point located between approximately 50% and approximately 85% of the distance between successive corner portions along each of the flat surfaces. Attached Figure Description

[0007] Some exemplary embodiments have been described in general terms. Now, reference will be made to the accompanying drawings, which are not necessarily drawn to scale, and in which:

[0008] Figure 1 A block diagram of a manual tool according to an exemplary embodiment is shown;

[0009] Figure 2 A complete side profile view of a manual tool according to an exemplary embodiment is shown;

[0010] Figure 3 It shows from Figure 2 A close-up side profile view of the end of the box of the hand tool according to an exemplary embodiment, taken from box 3;

[0011] Figure 4 It shows from Figure 3 A close-up side profile view of the end of the box of a hand tool according to an exemplary embodiment, taken from box 4; and

[0012] Figure 5 A close-up perspective view of the end of the box of a hand tool according to an exemplary embodiment is shown. Detailed Implementation

[0013] Some exemplary embodiments will now be described more fully below with reference to the accompanying drawings, which illustrate some, but not all, of the exemplary embodiments. In fact, the examples described and depicted herein should not be construed as limiting the scope, applicability, or configuration of this disclosure. Rather, these exemplary embodiments are provided to enable this disclosure to meet applicable legal requirements. The same reference numerals throughout the drawings denote the same elements. Furthermore, as used herein, the term “or” will be interpreted as a logical operator that results in a truth value whenever one or more of its operands are true. As used herein, an operative connection should be understood to involve a direct or indirect connection, in either case, that enables functional interconnection of components operatively coupled to each other.

[0014] As described above, some exemplary embodiments may involve providing a hand tool 100 with an improved design for engagement with fasteners. It is worth noting that in some embodiments, Figure 1 The hand tool 100 may be a combination wrench. Therefore, a combination wrench may include an open end and a housing end operably coupled to each other via a lever arm. While the improvements described herein may be described with reference to the housing end of a combination wrench, it should be understood that these improvements can be applied to other parts of the hand tool, such as the open end, and other types of hand tools. In this regard, in exemplary embodiments, the hand tool may be a socket wrench or a ratchet wrench. Thus, the housing end of the hand tool can be operably coupled to the lever arm via a ratchet assembly. In some cases, the housing end may be removably operably coupled to the hand tool.

[0015] Figure 1 A block diagram is shown of a hand tool 100 that can be configured to drive fasteners, including damaged fasteners. According to some embodiments, the hand tool 100 may be a wrench, a combination wrench, a socket wrench, or another similar tool for driving fasteners. Figure 2 A side profile view of the entire hand tool 100 is shown to illustrate the open end 110 and the box end 120 of the hand tool 100. Figure 3 It shows from Figure 2 The box 120 of the manual tool 100 according to the exemplary embodiment is a close-up side profile view taken from frame 3. Figure 4 It shows from Figure 3 The box 120 of the manual tool 100 according to the exemplary embodiment is a close-up side profile view taken from box 4. Figure 5 A close-up perspective perspective view of the box end 120 of a hand tool 100 according to an exemplary embodiment is shown.

[0016] Reference Figure 1The hand tool 100 may include at least a housing end 120 and a lever arm 130. The housing end 120 may be configured to operatively engage the hand tool 100 with a fastener 140 (e.g., a fastening nut such as a hex nut, a fastening head such as a hex head on a bolt or screw, or other fastener driven by a force applied to the periphery of the fastening nut or fastener head) so that the hand tool 100 can drive the fastener 140 relative to a working medium 150. In this respect, the working medium 150 may be any material or object capable of being operatively engaged with the fastener 140 in some way. In some embodiments, the lever arm 130 may be operatively engaged with the housing end 120 and may extend away from both the housing end 120 and the fastener 140. In this respect, in order to drive the fastener 140, the operator 160 may apply force to the lever arm 130 at the distal end of the lever arm 130, such that the hand tool 100 may apply a driving force (i.e., torque) on the fastener 140 via the box end 120, which may cause the fastener 140 to rotate about the axis of rotation 170 relative to the working medium 150.

[0017] In an exemplary embodiment, lever arm 130 can be rigidly and operably coupled to box end 120. Thus, box end 120 can be formed of the same material as lever arm 130 and can be integrated into the end of lever arm 130 accordingly. In this case, hand tool 100 and fastener 140 can rotate at a 1:1 ratio. For example, to allow fastener 140 to rotate a full rotation (i.e., 360 degrees), hand tool 100 can also rotate a full rotation simultaneously with fastener 140. If hand tool 100 encounters any object that might impede its rotation, box end 120 can be removed from fastener 140, hand tool 100 can be repositioned to allow free rotation again, box end 120 can be operably coupled back to fastener 140, and drive of fastener 140 can be restored. In some cases, lever arm 130 can be operably coupled to box end 120 via ratchet assembly 180. At this point, the operator 160 can continue to rotate the hand tool 100 and the fastener 140 at a 1:1 ratio, but it is no longer necessary to remove the housing end 120 from the fastener 140 to reposition the hand tool 100. In other words, the lever arm 130 can swing back and forth within an angular orientation range (e.g., within a 50° sector) to drive the fastener 140 relative to the working medium 150. Thus, due to the ratchet assembly 180, the housing end 120 can transmit driving force to the fastener 140 in response to movement of the hand tool 100 in a first direction (e.g., clockwise); however, the housing end 120 can transmit driving force to the fastener 140 without responding to movement of the hand tool 100 in a second direction opposite to the first direction (e.g., counterclockwise). In this case, the operation of the hand tool 100 can be similar to the operation of a ratchet wrench or a socket wrench. According to an exemplary embodiment, the hand tool 100 may also include an open end 110 disposed at the distal end of the lever arm 130 remote from the housing end 120. Therefore, in some embodiments, the hand tool 100 may be a combination wrench.

[0018] Figure 2A side profile view of the entire hand tool 100, including an open end 110 and a housing end 120, according to an exemplary embodiment, is shown. The open end 110, similar to the housing end 120, can be operatively coupled to a fastener 140 to drive the fastener 140 relative to a working medium 150. However, the open end 110 can be open (i.e., not closed) to allow the fastener 140 to enter and exit the open end 110 accordingly. In other words, the profile of the open end 110 can be a non-closed polygon, unlike the profile of the housing end 120. Thus, the open end 110 can include first, second, third, and fourth engaging surfaces (112, 114, 116, 118) within the open end 110, each engaging surface potentially engaging a corresponding flat surface 142 disposed at the fastener 140. Thus, the fastener 140 can be located in a plane that also includes the hand tool 100, and the fastener 140 can enter the open end 110 without either the hand tool 100 or the fastener 140 leaving the plane. The first and fourth engagement surfaces (112, 118) of the open end 110 can be parallel to each other and can be configured to engage with corresponding flat surfaces 142 on the fastener 140 that are also parallel to each other. Therefore, the distance measured between the first and fourth engagement surfaces (112, 118) can be substantially equal to the width of the fastener 140 measured between the pair of parallel flat surfaces 142.

[0019] Compared to the open end 110, the box end 120 can be closed on all sides and may resemble a ring in some ways, as the material can be arranged in a generally circular manner around the centrally located opening. Therefore, for the fastener 140 to enter the box end 120 of the hand tool 100, the fastener 140 or the hand tool 100 must be temporarily removed from the plane containing the other of the fastener 140 or the hand tool 100 so that the fastener 140 can be enclosed within the box end 120 and operably engaged thereto. Figure 2 In the illustrated embodiment, the hand tool 100 may be a combination wrench. In some other cases, as referred to above... Figure 1The hand tool 100 discussed may be a socket wrench. In this case, the housing end 120 may be operably coupled to the lever arm 130 via a ratchet assembly 180, and the distal end of the lever arm 130 may not include the open end 110. Typically, the size of the lever arm 130 may be selected based on the size of the fastener 140 with which the hand tool 100 is designed to work. In this regard, for example, if the hand tool 100 is designed to work with a 1 / 2-inch fastener 140, the size of the lever arm 130 may be selected to be at least large enough to be operably coupled to the 1 / 2-inch housing end 120 plus sufficient additional support material to allow a large amount of torque to be applied to the fastener 140 via the hand tool 100. In some cases, the hand tool 100 may be made of a metallic material, such as an iron alloy or a steel alloy.

[0020] Figure 3 It shows from Figure 2 The image shows a close-up side profile of the housing end 120 of a hand tool 100 according to an exemplary embodiment, taken from box 3. As described above, the housing end 120 may be the end of the hand tool 100 that engages with a fastener 140 to drive the fastener 140 in response to a driving force provided by the hand tool 100. Due to the closed annular structure of the housing end 120, the housing end 120 may include an engagement hole 190, which may engage with the fastener 140 via a corresponding flat surface 142 provided at the fastener 140. In this respect, the housing end 120 may be shaped as a substantially circular end that may be operatively coupled to the end of a lever arm 130. Thus, the engagement hole 190 may transmit driving force from the hand tool 100 to the fastener 140 to allow the hand tool 100 to drive the fastener 140.

[0021] like Figure 3 As shown, the engagement hole 190 may include instances of a plurality of clamping surfaces 200 that may extend parallel to and engage with corresponding flat surfaces 142 of the fastener 140 to operatively engage the engagement hole 190 with the fastener 140. In some embodiments, the engagement hole 190 may include a clamping surface 200 for each flat surface 142 disposed at the fastener 140. Thus, the fastener 140 may contact the engagement hole 190 at multiple instances of the clamping surfaces 200 and thus be operatively engaged to the engagement hole 190 therethrough. The engagement hole 190 may also include corner elimination regions 210 that may be disposed between successive instances of the clamping surfaces 200. In this respect, the fastener 140 may be driven via the clamping surfaces 200 while reducing force concentration at corner portions 144 of the fastener 140, which may be disposed at the intersection of successive flat surfaces 142.

[0022] The corner elimination region 210 may include a first surface 212 that defines the outer boundary of the corner elimination region 210 and a second surface 214 that extends from the first surface 212 to the clamping point 204. In some cases, the first surface 212 of the corner elimination region 210 may define the outermost boundary of the entire engagement hole 190. Figure 3 In the embodiment depicted, the first surface 212 of each of the corner elimination zones 210 can be positioned along a circle 220 drawn to connect each corner portion 144 of the fastener 140 and can be centered about the axis of rotation 170. At this point, the dimensions of the fastener 140 to which the hand tool 100 intends to operably engage can correspondingly determine the dimensions of the engagement hole 190. Thus, the first surface 212 of each corner elimination zone 210 can be arcuate, which can reduce the concentration of driving force at the corner portion 144 when the fastener 140 is driven.

[0023] exist Figure 3In some embodiments, the second surface 214 may be configured perpendicular to the corresponding flat surface 142 of the fastener 140. However, in some other cases, the second surface 214 may be arcuate, and in such cases, the second surface 214 may not be configured perpendicular to the flat surface 142. In this respect, the second surface 214 may intersect with multiple instances of the clamping surface 200 to form clamping points 204. The clamping points 204 can concentrate the driving force from the hand tool 100 at the clamping points 204 and correspondingly transmit the driving force to the fastener 140. Since the clamping points 204 of each of the multiple instances of the clamping surface 200 may be locations where the driving force is concentrated in the engagement hole 190, rather than sharp corners formed at right angles, the clamping points 204 may be rounded with a radius approximately between 2% and 10% of the width of the fastener 140 as measured perpendicularly between the parallel flat surfaces 142 of the fastener 140. In some cases, the radius of the fillet can even be between 2.5% and 3% of the width of the fastener 140, measured perpendicularly between the parallel flat surfaces 142. In other words, the clamping point 204 can be formed at the corner of the clamping surface 200 and the second surface 214. The rounding of the corner, which includes a radius of curvature rather than a sharp 90° angle, can be referred to as a fillet. Therefore, the clamping point 204 can be a fillet and can have a radius between approximately 2% and 10% of the width of the fastener 140, measured perpendicularly between the parallel flat surfaces 142 of the fastener 140. The fillet can be an important part of the engagement hole 190 because it can reduce the degree of damage to the fastener 140 caused by the actuation of the hand tool 100. Therefore, the clamping point 204 can use a rounded edge to transmit the driving force to the fastener 140 to clamp the fastener 140, which does a better job of holding the fastener 140 than a clamping point 204 that may be a sharp corner. Additionally, the rounded corner at clamping point 204 can also be used to retain clamping point 204. In this respect, the engagement hole 190 is less likely to wear after repeated use, and the hand tool 100 can therefore maintain its effectiveness for a longer period. Thus, a range of 2% to 10% of the width of the fastener 140, measured perpendicularly between the parallel flat surfaces 142, may be critical for the operation of the engagement hole 190. In this respect, clamping point 204 can provide an ideal radius such that there is sufficient traction to transmit the driving force to the fastener 140 without being too sharp and damaging the fastener 140 or the engagement hole 190 in the process. In some cases, clamping point 204 can allow the hand tool 100 to drive the fastener 140, which may have been stripped and / or damaged to a certain extent. Table 1 below includes the radii (R) of clamping points 204 that can correspond to the dimensions of a standard fastener 140.

[0024] Table 1: Clamping point radius for common fastener sizes.

[0025] Fastener dimensions Radius (R)·(mm) 8 mm 0.20< 9 mm 0.25<1 10 mm 0.25< 11mm< 0.30< 12·mm< 0.30< 13 mm 0.35< 14·mm< 0.35 15 mm 0.40 17 mm 0.45< 19 mm 0.50 1 / 4"< 0.20 5 / 16" 0.20 3 / 8" 0.25 7 / 16" 0.30 1 / 2" 0.35 9 / 16" 0.35< 5 / 8" 0.40 11 / 16" 0.45< 3 / 4" 0.50 7 / 8" 0.60

[0026] Figure 4 It shows from Figure 3 The image shows a close-up side profile of the end portion 120 of the box of the hand tool 100 according to an exemplary embodiment, taken from box 4. Figure 4 As shown, each of the plurality of instances of the clamping surface 200 can extend from the starting point 202 to the clamping point 204. The starting point 202 can be close to the corner elimination area 210 and can define the boundary between the corner elimination area 210 and the clamping surface 200. The corner elimination area 210 can actually be defined by the starting point 202 of the first clamping surface 200 to the clamping point 204 of the next successive clamping surface 200. The respective positions of the starting point 202 and the clamping point 204, as well as the length of the clamping surface 200, can be described relative to the fastener 140 and the flat surface 142 disposed at the fastener 140. At this point, Figure 4 Different contour segments, labeled A, B, and C, are depicted on the flat surface 142. For example, in some cases, multiple instances of the clamping surface 200 may extend from the starting point 202 to the clamping point 204, which may be set between 50% and 85% of the distance between successive corner portions 144 along each flat surface 142. In other words, Figure 4 The length of segment B can be between 50% and 85% of the length of segment A+B. In an exemplary embodiment, clamping point 204 can be located at 70% of the distance between successive corner portions 144. At this point, segment B can be approximately equal to 70% of the length of A+B, and therefore A can be approximately equal to 30% of the length of A+B.

[0027] The 30-70 ratio of segment A to segment B may be crucial for the efficient operation of the hand tool 100. In other words, with the clamping point 204 positioned at 70% of the distance between successive corner portions 144 along each flat surface 142, the engagement hole 190 can minimize damage to the fastener 140 due to driving it and maximize the driving force transmitted to the fastener 140. Therefore, the hand tool 100 can be operated more easily and efficiently by the operator 160, and the fastener 140 is safer.

[0028] Figure 4 The segment C in the text can refer to the distance starting from the corner portion 144 where the starting point 202 can be set. Therefore, multiple instances of the clamping surface 200 can begin at the starting point 202, which can be arranged between 0% and 30% of the distance between successive corner portions 144 along each of the flat surfaces 142. In other words, Figure 4The segment C in the middle can be approximately equal to 0% to 30% of the length of A+B. At this point, in response to the fastener 140 operably connected to the engagement hole 190, the corner portion 144 can be provided in the corner elimination zone 210. The starting point 202, located between 0% and 30% of the length of the flat surface 142, may be critical for the operation of the fastener 140 and for preventing the concentration of driving force at the corner portion 144.

[0029] Figure 5 A close-up perspective view of the box end 120 of a hand tool 100 according to an exemplary embodiment is shown. Figure 5 In the perspective view, other dimensions of the engagement hole 190 may be more apparent. In some cases, the depth of the engagement hole 190 may be approximately equal to the depth of the head of the fastener 140. In some cases, the engagement hole 190 may include a tapered shape toward a rotation axis 170 extending through the end of the housing 120. In other words, if the hole of the engagement hole 190 includes a first plane disposed at the top of the end of the housing 120 and a second plane disposed at the bottom of the end of the housing 120 and parallel to the first plane, then if the engagement hole 190 includes a tapered shape, the profile (i.e., cross-section) of the engagement hole 190 at the first plane may be larger than the profile (i.e., cross-section) of the engagement hole 190 at the second plane. Thus, if the engagement hole 190 is tapered, the engagement hole 190 can be self-fastened to the fastener 140 by being operably engaged to the fastener 140 at the wider (i.e., larger) end of the engagement hole 190. However, in an exemplary embodiment, the engagement hole 190 may extend parallel to the axis of rotation 170 extending through the end of the housing 120, or in other words, the engagement hole 190 may not include the tapered portion. In some cases, the hand tool 100 may be bidirectional. In this case, the engagement hole 190 may apply a driving force to the fastener 140 to loosen or tighten the fastener 140. In an exemplary embodiment, the hand tool 100 is only unidirectional, and additional hand tools 100 may be required to loosen and tighten the fastener 140.

[0030] Some exemplary embodiments may provide a tool for driving a fastener. The tool may include: a housing end configured to engage a fastener; and a lever arm operably coupled to and extending away from the housing end. A female threaded end may engage the fastener via an engagement hole. The engagement hole may include multiple instances of clamping surfaces extending parallel to a respective flat surface of the fastener to operably engage the engagement hole with the fastener, allowing the fastener to be driven while avoiding contact with corner portions of the fastener that may be disposed at intersections with the flat surfaces. The multiple instances of clamping surfaces may extend from a starting point to a clamping point, the clamping point being disposed between approximately 50% and approximately 85% of the distance between successive corner portions along each of the flat surfaces.

[0031] Tools in some embodiments may include additional features, modifications, enhancements, and / or similar additions to achieve further purposes or enhance tool performance. Additional features, modifications, additions, etc., can be added in any combination of each other. Below is a list of various additional features, modifications, and additions, each of which can be added individually or in any combination of each other. For example, the clamping point may be a rounded corner having a radius approximately between approximately 2% and approximately 10% of the width of the fastener as measured perpendicularly between corresponding parallel flat surfaces of the fastener. In some cases, the engagement hole may also include a corner elimination region arranged between successive instances of the clamping surfaces. In one exemplary embodiment, the corner elimination region may include a first surface defining the outer boundary of the corner elimination region and a second surface extending from the first surface to the clamping point. In some cases, the first surface of the corner elimination region may be arranged along a circle drawn to connect each corner portion of the fastener. In an exemplary embodiment, the second surface may be arranged perpendicular to the corresponding flat surface of the fastener. In some cases, the second surface may be arcuate. In an exemplary embodiment, the plurality of instances of the clamping surface may begin at a starting point located between approximately 0% and approximately 30% of the distance between successive corner portions along each of the flat surfaces. In some cases, the clamping point may be located at approximately 70% of the distance between successive corner portions along each of the flat surfaces. In an exemplary embodiment, the engagement hole may taper toward a rotational axis extending through the end of the housing for operably engaging with the fastener. In some cases, the engagement hole may be parallel to the rotational axis extending through the end of the housing for operably engaging with the fastener. In an exemplary embodiment, the end of the housing may be operably engaged to the lever arm via a ratchet assembly. In some cases, the tool may be a combination wrench.

[0032] Some exemplary embodiments may provide an engagement hole for engaging and driving a fastener with a tool. The engagement hole may include multiple instances of clamping surfaces extending parallel to respective flat surfaces of the fastener to operatively connect the engagement hole and the fastener, such that the fastener can be driven while avoiding contact with corner portions of the fastener located at intersections of the flat surfaces. The multiple instances of the clamping surfaces may extend from a starting point to a clamping point located between approximately 50% and approximately 85% of the distance between successive corner portions along each of the flat surfaces.

[0033] Benefiting from the teachings presented in the foregoing description and associated drawings, those skilled in the art will conceive of many modifications and other embodiments of the invention set forth herein. Therefore, it should be understood that the invention is not limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Furthermore, while the foregoing description and associated drawings describe exemplary embodiments in the context of certain exemplary combinations of elements and / or functions, it should be understood that different combinations of elements and / or functions may be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, combinations of elements and / or functions different from those explicitly described above are also contemplated as being set forth in some of the appended claims. Where advantages, benefits, or solutions to problems are described herein, it should be understood that such advantages, benefits, and / or solutions may apply to some exemplary embodiments but not necessarily to all exemplary embodiments. Therefore, any advantages, benefits, or solutions described herein should not be considered critical, necessary, or essential to all embodiments or the embodiments claimed herein. Although specific terms are used herein, they are used only in a general and descriptive sense and not for limiting purposes.

Claims

1. A tool for driving fasteners, the tool comprising: The end of the box is configured to engage with fasteners; as well as A lever arm, operably coupled to the end of the box and extending away from the end of the box, The end of the box engages with the fastener via a meshing hole. The engagement hole includes multiple instances of clamping surfaces extending parallel to the respective flat surfaces of the fastener, operably connecting the engagement hole and the fastener such that the fastener can be driven while avoiding contact with corner portions of the fastener located at intersections with the flat surfaces. The plurality of instances of the clamping surface extend from the starting point to the clamping point, the clamping point being located between approximately 50% and approximately 85% of the distance between successive corner portions along each of the flat surface.

2. The tool according to claim 1, wherein, The clamping point is a rounded corner, the radius of which is approximately between 2% and 10% of the width of the fastener as measured perpendicularly between the corresponding parallel flat surfaces of the fastener.

3. The tool according to claim 1, wherein, The engagement hole also includes corner elimination zones arranged between successive instances on the clamping surface. The corner elimination area includes a first surface defining the outer boundary of the corner elimination area and a second surface extending from the first surface to the clamping point.

4. The tool according to claim 3, wherein, The first surface of the corner elimination zone is set along a circle drawn to connect each corner portion of the fastener.

5. The tool according to claim 3, wherein, The second surface is configured to be a flat surface perpendicular to the fastener.

6. The tool according to claim 3, wherein, The second surface is arc-shaped.

7. The tool according to claim 1, wherein, The plurality of instances of the clamping surface begin at a starting point, which is set between approximately 0% and approximately 30% of the distance between successive corner portions along each of the flat surfaces.

8. The tool according to claim 1, wherein, The clamping point is located at approximately 70% of the distance between successive corner portions along each of the flat surface.

9. The tool according to claim 1, wherein, The engagement hole tapers gradually toward the axis of rotation extending through the end of the housing to allow for operable engagement with the fastener.

10. The tool according to claim 1, wherein, The engagement hole is parallel to the axis of rotation extending through the end of the housing, for operably engaging with the fastener.

11. The tool according to claim 1, wherein, The end of the box is operably connected to the lever arm via a ratchet assembly.

12. An engagement hole for engaging and driving a fastener with a tool, the engagement hole including a plurality of instances of clamping surfaces extending parallel to respective flat surfaces of the fastener to operably connect the engagement hole and the fastener, such that the fastener can be driven while avoiding contact with corner portions of the fastener disposed at intersections of the flat surfaces, and in, The plurality of instances of the clamping surface extend from the starting point to the clamping point, the clamping point being located between approximately 50% and approximately 85% of the distance between successive corner portions along each of the flat surface.

13. The meshing hole according to claim 12, wherein, The clamping point is a rounded corner, the radius of which is between approximately 2% and approximately 10% of the width of the fastener as measured perpendicularly between the corresponding parallel flat surfaces of the fastener.

14. The meshing hole according to claim 12, wherein, The engagement hole also includes corner elimination zones arranged between successive instances on the clamping surface. The corner elimination area includes a first surface defining the outer boundary of the corner elimination area and a second surface extending from the first surface to the clamping point.

15. The engagement hole according to claim 14, wherein, The first surface of the corner elimination zone is arranged along a circle drawn to connect each corner portion of the fastener.

16. The engagement hole according to claim 14, wherein, The second surface is configured to be a flat surface perpendicular to the fastener.

17. The engagement hole according to claim 14, wherein, The second surface is arc-shaped.

18. The meshing hole according to claim 12, wherein, Multiple instances of the clamping surface begin at a starting point, which is set between approximately 0% and approximately 30% of the distance between successive corner portions along each of the flat surfaces.

19. The meshing hole according to claim 12, wherein, The clamping point is located at approximately 70% of the distance between successive corner portions along each of the flat surface.

20. The meshing hole according to claim 12, wherein, The engagement hole is located inside the housing of the combination wrench.

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