Tap holder for multiple tap sizes

A tap holder includes a body extending along an axis and having a front end portion defining a front opening and an externally threaded portion. A gripping assembly includes a spring having first and second legs, a first jaw mounted to the first leg, and a second jaw mounted to the second leg. Each jaw has a tapered outer wall and an inner wall with the inner walls of the jaws facing each other. A sleeve has an internally threaded bore threadably received on the externally threaded portion of the body, and an inner tapered surface configured to abut the tapered outer walls of the first and second jaws. As the sleeve is rotated relative to the body, a distance between the first and second gripping surfaces may be adjusted for gripping a tap between the inner walls of the first and second jaws. Each of the inner walls includes first and second gripping surfaces, the first gripping surfaces defining a first width therebetween for gripping taps having a first range of head sizes, and the second gripping surfaces defining a larger second width therebetween for gripping taps having a second, different range of head sizes.

TECHNICAL FIELD

This application relates to holder for holding multiple sizes of taps.

BACKGROUND

Taps are used to cut threaded holes in workpieces such as metal sheets and plates. A tap generally has a polygonal (e.g., square) head, an intermediate shank, and a threaded working end used to cut (or tap) threads in a hole. A tap may be gripped by a tap holder to facilitate coupling the tap to a hand tool or a power tool. However, existing tap holders are limited in the range of sizes of taps that the tap holder is able to receive. This requires users to purchase several different sizes of tap holders, which is both costly and inconvenient.

SUMMARY

In an aspect, a tap holder includes a body extending along an axis and having a front end portion defining a front opening and an externally threaded portion. A gripping assembly includes a spring having first and second legs, a first jaw mounted to the first leg, and a second jaw mounted to the second leg. Each jaw has a tapered outer wall and an inner wall with the inner walls of the jaws facing each other. A sleeve has an internally threaded bore threadably received on the externally threaded portion of the body, and an inner tapered surface configured to abut the tapered outer walls of the first and second jaws. As the sleeve is rotated relative to the body, a distance between the first and second gripping surfaces may be adjusted for gripping a tap between the inner walls of the first and second jaws. Each of the inner walls includes first and second gripping surfaces, the first gripping surfaces defining a first width therebetween for gripping taps having a first range of head sizes, and the second gripping surfaces defining a larger second width therebetween for gripping taps having a second, different range of head sizes.

Implementations of this aspect may include one or more of the following features. The tap holder may include a rod-shaped handle received in a cross-bore defined in the body transverse to the axis. The handle may include a plurality of recesses along its length and the body may include a detent projecting into the cross-bore to engage the recesses to adjust a transverse position of the handle relative to the body. The body may define an axial socket in a rear end of the body for receiving a driving tool. The socket may have a polygonal cross-section. The spring may be a wire spring. The wire spring may be generally U-shaped with a cross-bar and the legs attached to ends of the cross-bar. Each leg may have a first section extending axially forward and radially inward from the cross-bar at a first angle, a second section extending axially forward and radially outward from the first section at a second angle, and a third section extending axially forward and radially outward from the second section at a third angle. Each of the first gripping surfaces and each of the second gripping surfaces ma be V-shaped for gripping square heads of taps. The second gripping surfaces may be positioned closer to the front end of the body than the first gripping surfaces. A step may be defined between each of the first gripping surfaces and the second gripping surfaces. The first gripping surfaces are configured to hold taps having head widths of less than or equal to 5 mm, e.g., approximately 2 mm to 5 mm. The second gripping surfaces may configured to hold taps having head widths of greater than or equal to 4 mm, e.g., approximately 4 mm to 7 mm.

In another aspect, a tap holder includes a body extending along an axis and having a front end portion defining a front opening and an externally threaded portion. A gripping assembly includes a generally U-shaped wire spring having a cross-bar and first and second legs at ends of the cross-bar, a first jaw mounted to the first leg, and a second jaw mounted to the second leg. Each jaw has a tapered outer wall and an inner wall with the inner walls of the jaws facing each other. A sleeve has an internally threaded bore threadably received on the externally threaded portion of the body, and an inner tapered surface configured to abut the tapered outer walls of the first and second jaws. As the sleeve is rotated relative to the body, a distance between the first and second gripping surfaces may be adjusted for gripping a tap between the inner walls of the first and second jaws. Each leg has a first section extending axially forward and radially inward from the cross-bar at a first angle a second section extending axially forward and radially outward from the first section at a second angle, and a third section extending axially forward and radially outward from the second section at a third angle.

Implementations of this aspect may include one or more of the following features Each of the inner walls may include first and second gripping surfaces. The first gripping surfaces may define a first width threbetween for gripping taps having a first range of head sizes, and the second gripping surfaces may define a larger second width therebetween for gripping taps having a second, different range of head sizes. Each of the first gripping surfaces and each of the second gripping surfaces may be V-shaped for gripping square heads of taps therebetween. The second gripping surfaces may be positioned closer to the front end of the body than the first gripping surfaces

Advantages may include one or more of the following. For example, the multiple gripping surfaces of differing widths enable a single tap holder to hold taps having multiple ranges of tap head sizes, enabling the user to use a single tap holder for a wider range of taps. The shape of the legs of the spring facilitate improved retention of the jaws on the spring. These and other advantages and features will be apparent from the description, the drawings, and the claims.

DETAILED DESCRIPTION

Referring toFIGS. 1 and 2, in one implementation, a tap holder10includes a generally cylindrical body20, a gripping assembly50, an adjustment sleeve80, and a handle90. The tap holder10is adapted to hold a plurality of different sized taps12. Each tap12includes a polygonal (e.g., square) head14, an intermediate shank16and a front tapping portion18having a plurality of threads19adapted to cut a threaded hole in a workpiece.

Referring also toFIGS. 3A and 3B, the body20extends generally along an axis X and includes a rear portion22, an intermediate portion24, and a front portion26. The rear portion22includes an enlarged head23that defines an axially extending polygonal (e.g., square) socket28configured to receive a driving tool such as a square head of a socket wrench or impact wrench. The handle90comprises a rod-shaped shaft92having a plurality of annular recesses94at different locations along the length of the shaft92. The enlarged head23includes a transverse throughbore30for receiving the handle90. The rear portion22also defines an axial bore25that receives a spring27and a detent ball or pin29that is configured to project partially into the througbore30for engaging the recesses94in the handle90. In this manner, the handle90can be retained in the cylindrical body20at a plurality transverse positions as determined by the positions of the annular recesses94.

The intermediate portion24of the body20comprises a cylindrical bore31, a transverse slot33, and an externally threaded cylindrical outer surface32for receiving the sleeve80. The front portion26includes a pair of legs34defining a space40between the legs34. Each leg38has a semi-cylindrical rear outer surface36, a tapered front outer surface38, and an inner surface42with an axially extending concave recess44. The cylindrical bore31, the transverse slot33, and the space40between the legs38together define a front opening that is configured to receive the gripping assembly50, as described further below.

Referring alsoFIG. 4A-4C, the gripping assembly50includes a generally U-shaped wire spring52having a cross-bar54and a pair of legs56extending axially forward of the cross-bar54. Each leg56includes a first portion58extending axially forward and radially inward from the cross-bar54at a first acute angle θ1(e.g., approximately 68° to approximately 74°), a second portion60extending axially forward and radially outward from the first portion58at a second obtuse angle θ2(e.g., approximately 136° to approximately 150°), and a third portion62extending axially forward and radially outward from the second portion62at a third obtuse angle θ3(e.g., approximately 155° to approximately 165°).

The gripping assembly50also includes a pair of jaws64each having an axial bore66for receiving the second portion60and the third portion62of each of the legs56. The third portion62is angled radially outward from the second portion62to help retain the jaws64on the legs56. Each jaw64also includes an outer wall68with a semi-cylindrical rear portion70and a tapered front portion72, and an inner wall69with a first polygonal (e.g., V-shaped) gripping surface74and a second polygonal (e.g., V-shaped) gripping surface76, separated by a step78. The first and second gripping surfaces74,76of the respective jaws64face one another to define a first width W1(e.g., approximately 3.68 mm to 5.80 mm) and a second larger width W2(e.g., approximately 5.80 mm to 10.32 mm) therebetween (with the widths W1, W2measured from the apexes of the V-shapes).

Referring also toFIGS. 5A and 5B, the first gripping surfaces74with a smaller width W1are adapted to clamp taps12A having polygonal heads14A with a first range of smaller widths (e.g., less than or equal to approximately 5 mm, such as approximately 2 mm to 5 mm, measured corner to corner). The second gripping surfaces76with a larger width W2are adapted to clamp taps12B having polygonal heads14B with a second range of larger maximum widths (e.g., greater than or equal to approximately 4 mm, such as approximately 4 mm to 7 mm, measured corner to corner). It should be noted that the first range of tap sizes of taps may overlap partially or may be distinct from the second range of tap sizes.

Referring also toFIG. 6, the outer sleeve80includes a generally cylindrical rear portion82with an internally threaded bore84configured to be threadably received over the externally threaded cylindrical outer surface32of the body20, and a knurled external surface85configured to be gripped by a user's fingers. The outer sleeve80also has a frustronconical front portion86with a smooth outer surface87and a tapered inner surface88configured to abut against the tapered front portions72of the outer walls68of the jaws64, and against the tapered front outer surfaces38of the legs26.

The tap holder10is assembled by inserting the legs56of the spring52into the bores66in the jaws68to form the gripping assembly50. The gripping assembly50is receive d in the front opening of the body20by inserting the cross bar54of the spring52into the transverse slot33with the jaws68received in the spaces40between the legs34. The adjustment sleeve80is received over the jaws40and legs34and threaded onto the externally threaded outer surface32of the body20. Finally, the handle90may be optionally inserted into the transverse bore30in the body and retained by the detent pin29at one of the plurality of annular recesses94in the handle90.

In use, a tap12is inserted into the front opening of the body20between the jaws64and the legs34of the body20. Depending on the size of the head14of the tap12, the head14may be received between the first gripping surfaces74of the jaws64(for heads having a smaller width) and/or between the second gripping surfaces76of the jaws (for heads having a larger width). The sleeve80may then be rotated along the threaded surfaces32,84so that the tapered internal surfaces88of the sleeve80push against the tapered external surfaces72of the jaws64to move the jaws64axially forward and radially inward towards one another to tighten the grip of the jaws64about the head14of the tap12. Once the tap12is securely retained between the jaws64, the tap holder10can be rotated to cause the tap12to cut a threaded hole in a workpiece. The tap holder10may be rotated manually (e.g., by grasping the handle90and manually rotating the holder10, or by attaching a manual ratchet wrench to the socket28), or by using a power tool (e.g., a drill, a screwdriver, an impact driver, or an impact wrench) by coupling a working end of the power tool to the socket28. Once a hole has been formed, the tap12may be removed from the tap holder10by rotating the sleeve80in the opposite direction to loosen the grip of the jaws64on the head14of the tap12.

Terms of degree such as “generally,” “substantially,” “approximately,” and “about” may be used herein when describing the relative positions, sizes, dimensions, or values of various elements, components, regions, layers and/or sections. These terms mean that such relative positions, sizes, dimensions, or values are within the defined range or comparison (e.g., equal or close to equal) with sufficient precision as would be understood by one of ordinary skill in the art in the context of the various elements, components, regions, layers and/or sections being described.

Numerous modifications may be made to the exemplary implementations described above. For example, in other implementations, the tap holder may have a different number of jaws (such as three or four), the polygonal geometry between the jaws may be a different (e.g., hexagonal or pentagonal), and the polygonal geometry of the socket may be different (e.g., hexagonal or pentagonal). The jaws may each include more than two gripping surfaces (e.g., three or four gripping surfaces) of different widths to facilitate grasping a wider range of tap head sizes. These and other implementations are within the scope of the following claims.