GOLF PUTTER HEADS AND METHODS OF MAKING THEM

Abstract

Golf putter heads have a one-piece heat treated high hardness stainless steel body having an upstanding wall with a striking face, and directly behind it, a downwardly disposed thin unbounded through-cavity to provide distinct repeatable audible feedback. The putter heads can have a centrally located rearwardly extending mass of body material in the form of an integral spherical mound to provide balance and a high moment of inertia. Methods of making the putter heads are disclosed.

Description

CROSS REFERENCE TO RELATED APPLICATION

This application is based on and claims the benefit of Provisional Application Ser. No. 60/898,829, filed Feb. 1, 2007.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to golf clubs, and more particularly to golf putter heads that impart improved feel to the user.

2. Description of Related Art

Most conventional putters are made of soft materials. Some have face inserts made of aluminum, brass, plastic or non-metallic materials. The intention is that the soft materials will impart a desirable roll to the golf ball when it is struck with the putter face.

However, putter heads that are made of soft materials are limited in their applications. For example, they are not suitable for rough treatment environments because they tend to dent, scratch, mar or corrode. Also, because of their low carbon content, they are not suitable for heat treatment to increase their hardness to provide putter heads with the durability advantages provided by highly hardened steel. Further, putter heads that have inserts made of soft materials set into or applied on the putter face have been found lacking in terms of not providing sufficient, significant, reliable or repeatable feel or feedback to the user to indicate when the ball is being struck directly on the sweet spot of the face of the head, as compared to being struck by a portion of the club face that is not aligned with or is off of the sweet spot. Putter heads that have inserts made of soft materials have been found undesirable at times because the inserts are subject to distortion of the striking area due to the difference in the thermal coefficients between differing materials of the insert and the head. Also, the inserts and adhesives that secure the inserts can be affected by the ambient temperatures to which they are subjected. For example, a golf club that is stored in a car trunk or garage may experience temperatures that range from below zero to extremely high. These inserts may lose their originally intended softness or inherent hardness due to such temperature fluctuations.

SUMMARY OF THE DISCLOSURE

The present disclosure provides golf putter heads of the mallet or blade type that overcome the aforementioned and other problems and/or disadvantages.

The present disclosure provides golf putter heads that provide improved sufficient, significant, reliable and repeatable feel or feedback to the user relative to whether a golf ball is aligned with the sweet spot of the putter face when the striking face strikes the ball.

The present disclosure provides golf putter heads that will ring with a distinct sound like that of a tuning fork when a golf ball is properly stroked on the sweet spot of the striking face, thereby offering an audible feedback to the user.

The present disclosure also provides golf putter heads that impart to the user's hands a more pronounced feeling of contact with the golf ball when it is stroked with a putter head of this disclosure.

The present disclosure also provides golf putter heads that are one-piece.

The present disclosure also provides golf putter heads that are one-piece and are of the heavy type.

The present disclosure further provides golf putter heads that have a unique unbounded through-cavity located behind, preferably directly behind, the striking face of the putter head.

The present disclosure further provides golf putter heads having an unbounded through-cavity that can have an elliptical shape.

The present disclosure yet further provides the aforementioned and other golf putter heads having a high moment of inertia.

The present disclosure further provides the aforementioned and other golf putter heads that have a high moment of inertia, and are properly balanced without need of adjustments to the head.

The present disclosure yet further provides the aforementioned and other golf putter heads having a high moment of inertia that in turn provides resistance to substantially horizontal twisting of the putter head or putter during use.

The present disclosure yet further provides the aforementioned and other golf putter heads having a high moment of inertia due to the presence of a mass of the putter head material located along the longitudinal axis of the putter head.

The present disclosure yet further provides the aforementioned and other golf putter heads having a high moment of inertia provided by a spherical mound of the putter head material.

The present disclosure yet further provides the aforementioned and other golf putter heads having a high moment of inertia provided by a spherical mound of the putter head material located preferably immediately behind and central to the elliptical unbounded through-cavity and providing downward and rearward weight to the putter head.

The present disclosure yet further provides the aforementioned and other golf putter heads that are made of heat treated stainless steel.

The present disclosure yet further provides the aforementioned and other golf putter heads that are made of a high hardness stainless steel.

The present disclosure yet further provides the aforementioned and other golf putter heads that are made of a heat treated, tempered, high hardness stainless steel that can have a Rockwell hardness of from about 44 to about 52, preferably from about 44 to about 47, on the Rockwell C Scale.

The present disclosure still further provides golf putter heads whose striking face has a texture comprised of an array of dimples, preferably uniform dimples.

The present disclosure still further provides golf putter heads whose striking face has a texture comprised of at least 10,000 dimples per square inch of the striking face.

The present disclosure further provides golf putter heads whose striking face provide a true roll (without an imparted hop or side spin) to a golf ball when it is stroked with the striking face.

The present disclosure further provides golf putter heads that will not dent, scratch, mar or corrode under normal conditions of use.

These and other objects and advantages of the present disclosure are provided by golf putter heads of the present disclosure that can have a selected combination of aspects and features, including from the following: that they are one-piece, made of a heat treatable stainless steel that is heat treated and tempered to a Rockwell hardness of from about 44 to about 52, preferably from about 44 to about 47 on the Rockwell C-Scale, have a contact wall having a striking face with a sweet spot, have an unbounded through-cavity that extends through the putter head preferably directly behind the striking face, have a spherical mound of the putter head material directly behind and central to the elliptical unbounded through-cavity, and have a striking face with an array of dimples therein, the golf putter heads providing a distinct audible feedback sound and feel to the user depending on where on the striking face the golf ball is struck.

The present disclosure also provides embodiments of methods of making an aforementioned or other golf putter head of the disclosure.

Other advantages and features of the present disclosure will be understood by reference to the following:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top front perspective view of an embodiment of a mallet style golf putter head of the disclosure;

FIG. 2 is a top left rear perspective view of the golf putter head of FIG. 1;

FIG. 3 is a top plan view of the putter head of FIG. 1;

FIG. 4 is a rear elevational view as would be seen along line 4-4 of the putter head of FIG. 3, if the putter head of FIG. 3 were inverted;

FIG. 4A is an enlarged view of the encircled portion of FIG. 4;

FIG. 5 is a front elevational view as would be seen along line 5-5 of FIG. 3 showing the textured front striking face of the putter head of FIG. 3;

FIG. 6 is a vertical sectional view as would be seen along line 6-6 of FIG. 3;

FIG. 7 is a sectional view as would be seen along line 7-7 of FIG. 6;

FIG. 8 is an enlarged view of the encircled portion of the textured front striking face of the putter head of FIG. 5;

FIG. 9 is a vertical sectional view through the enlarged encircled portion of the striking face of the putter head as basically would be seen along line 9-9 of FIG. 5;

FIG. 10 is a greatly enlarged schematic vertical sectional view as would be seen of a portion of the textured face of the putter head shown in FIG. 9;

FIG. 11 is a top front perspective view of a blade type embodiment of the putter head of the disclosure;

FIG. 12 is a top plan view of the blade type putter head embodiment shown in FIG. 11;

FIG. 13 is a front elevation of the blade type putter head embodiment as would be seen along line 13-13 of FIG. 12, if the putter head of FIG. 12 were inverted;

FIG. 14 is a side elevation of the blade type putter head embodiment as would be seen along line 14-14 of FIG. 12; and

FIG. 15 is a side elevation of the blade type putter head embodiment as would be seen along line 15-15 of FIG. 12.

FIG. 16 is a top front perspective view of a second embodiment of a mallet style golf putter head of the disclosure;

FIG. 17 is a top left rear perspective view of the golf putter head of FIG. 16;

FIGS. 18 and 18A are top plan view of the putter head of FIG. 16;

FIG. 19 is a front elevational view showing the front face of the putter head of FIG. 18;

FIG. 20 is a rear elevational view of the putter head of FIG. 18;

FIG. 20A is a bottom plan view of the putter head of FIG. 18;

FIG. 20B is a rear perspective view of the bottom of the putter head of FIG. 20A;

FIG. 20C is a right side elevational view of the putter head of FIG. 18;

FIG. 20D is a left side elevational view of the putter head of FIG. 18;

FIG. 21 is a vertical sectional view as would be seen along line 21-21 of FIG. 19;

FIG. 22 is a horizontal sectional view as would be seen along line 22-22 of FIG. 21;

FIG. 23 is a horizontal sectional view as would be seen along line 23-23 of FIG. 21;

FIG. 24 is a top front perspective view of a second embodiment of the blade type putter head of the disclosure;

FIG. 25 is a top left rear perspective view of the blade type putter head of FIG. 24;

FIG. 26 is a top plan view of the blade type putter head of FIG. 25;

FIG. 27 is a front elevation of the blade type putter head of FIG. 26;

FIG. 28 is a rear elevation of the blade type putter head of FIG. 26;

FIG. 28A is a bottom plan view of the blade type putter head of FIG. 26;

FIG. 28B is a rear perspective view of the bottom of the blade type putter head of FIG. 26;

FIG. 28C is a right side elevational view of the blade type putter head of FIG. 26, as would be seen along line 28C-28C of FIG. 26;

FIG. 28D is a left side elevational view of the blade type putter head of FIG. 26, as would be seen along line 28D-28D of FIG. 26; and

FIG. 29 is a vertical sectional view of the blade type putter head of FIG. 26, as would be seen along line 29-29 of FIG. 27.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Referring to the drawings in detail, particularly to the perspective views of FIGS. 1 and 2, there is shown an embodiment of a mallet style golf putter head of the disclosure. More particularly, these Figures show a mallet style golf putter head, generally designated 10, comprised of a one-piece body 12 having a front F, a rear R, a front-to-rear longitudinal axis LA, a transverse axis TA, and a heel H and a toe T oppositely disposed on a transverse axis TA.

Body 12 has an upstanding wall 14 whose length extends generally transverse to longitudinal axis LA and whose width extends generally along longitudinal axis LA. Upstanding wall 14 has a top surface 16, a bottom surface 18, a front portion 20 and a rear portion 22.

Front portion 20 of upstanding wall 14 extends generally between heel H and toe T, and is comprised of a contact wall 24 having a front striking face 26 and a rear wall surface 28. Upstanding wall 14 is also comprised of a downwardly disposed unbounded through-cavity 30, the through-cavity 30 being directly behind striking face 26, transverse to the longitudinal axis and extending from and through top and bottom surfaces 16, 18 of upstanding wall 14. Through-cavity 30 has a front wall surface 32 that forms, i.e., is the same as rear wall surface 28 of contact wall 24.

Referring to FIGS. 3 through 5, FIG. 3 is a top plan view of golf putter head 10 of FIG. 1, FIG. 4 is a rear elevational view as would be seen along line 4-4 of FIG. 3, and FIG. 5 is a front elevational view as would be seen along line 5-5 of FIG. 3. FIGS. 3 through 5 show that through-cavity 30 preferably has an elliptical shape when seen in top plan view or in horizontal section. The preferred elliptical shape is configured such that through-cavity 30 has a convex central portion that extends forwardly toward striking face 26. FIGS. 3 through 5 (and 7) also show that the portions of front and rear surfaces 32, 34 of through-cavity 30 that define sweet spot SS and central portion 36 of through-cavity 30 are spaced relatively closer to each other than are the portions of wall surfaces 32′, 34′ that are at or adjacent the end portions of through-cavity 30.

It is contemplated that when seen in top plan view or in horizontal section, through-cavity 30 can have the general shape of the outer surface of an open umbrella whose apex is toward and aligned with central portion 36 of front striking face 26. Through-cavity 30 can also have the general shape of a bow whose convex surface is toward, and whose ends are bowed away from striking face 26.

FIGS. 3 through 5 and FIGS. 6 and 7 show that front striking face 26 (of contact wall 24 of front portion 20 of upstanding wall 14) preferably has a sweet spot SS on longitudinal axis LA. These Figures also show that elliptically-shaped through-cavity 30 is defined by cavity front wall surface 32 that is coincident with, i.e., one and the same as, rear wall surface 28 of contact wall 24, by cavity rear wall surface 34 and by opposed enclosing cavity end wall surfaces 35. Front wall surface 32 and rear wall surface 28 of through-cavity 30 define a relatively thinner central portion 36 of the through-cavity 30 that extends to either side of sweet spot SS. Opposed end portions 35 of through-cavity 30 define wider end portions of through-cavity 30. As shown, preferably thinner central portion 36 of through-cavity 30 is located behind, preferably directly behind and adjacent either side of sweet spot SS. The wider end portions of through-cavity 30 are located adjacent respective heel H and toe T portions of upstanding wall 14.

In a preferred embodiment of the disclosure, and as shown in FIGS. 1 through 4A, top surface 16 of upstanding wall 14 includes an alignment groove 40 that runs along longitudinal axis LA and is orthogonal to and joins central portion 36 of through-cavity 30 at or just behind sweet spot SS.

Front portion 20 of top surface 16 of upstanding wall 14 merges into rear portion 22 of upstanding wall 14. Rear portion 22 is comprised of an upper, downwardly depending rim 42 that merges into a concave surface portion 44 that transitions adjacent base 46 of upstanding wall 14, into a rearwardly extending surface 48 that extends toward rear R of body 12. Rearwardly extending surface 48 and concave surface portion 44 of the rear portion 22 of upstanding wall 14 each include a portion of alignment groove 40, and those portions of alignment groove 40 are in alignment with each other and with the portion of alignment groove 40 that traverses top surface 16 of upstanding wall 14.

Referring mainly now to FIGS. 6 and 7, front striking face 26 preferably is substantially flat and is disposed at a rearward or loft angle La of from about 3 degrees to about 5 degrees, preferably 3 or 4 degrees, measured from the junction of front striking face 26 and of bottom surface 18 of upstanding wall 14 to the junction of front striking face 26 and top surface 16 of upstanding wall 14. Alignment groove 40 is orthogonal to and abuts or intersects through-cavity 30.

Through-cavity 30 preferably is disposed generally parallel to the angle of striking face 26. The width of through-cavity 30, from front to rear, preferably is uniform through a vertical section of upstanding wall 14 from its top surface 16 to its bottom surface 18. The vertical section taken through line 6-6 of FIG. 3 is taken along alignment groove 40 and consequently through sweet spot SS, where through-cavity 30 is thinnest. As can be seen from FIGS. 6 and 7, the width of through-cavity 30 remains uniform from top surface 16 to bottom surface 18 at whatever point the section line is taken through upstanding wall 14 and through-cavity 30, but as seen from FIG. 7, the uniform width of through-cavity 30 at each section line progressively made through through-cavity 30 will be wider as the section lines are progressively made further and further away from sweet spot SS progressively toward through-cavity opposed end portions 35.

Through-cavity 30 can be of any suitable size, shape, thickness and/or location behind contact wall 24, so long as the through-cavity creates a cushioning effect that softens the putting striking blow when putter head 10 strikes a golf ball especially at the sweet spot, creates a true ball roll off of striking face 26, and provides a definite, distinguishable feeling and a definite repeatable frequency sound vibration when sweet spot SS of a particular embodiment of the disclosure is struck during the putting stroke. Suitable spacing between the front and rear wall surfaces at the central portion of the through-cavity behind sweet spot SS, and desirably within about, 250″ to either side of the sweet spot of embodiments of the putter heads of the disclosure, is in the range between about 0.070″ to about 0.090″, and preferably is about 0.080″.

FIGS. 8, 9 and 10 show features of textured front striking face 26 of putter head 10 of the disclosure. Although FIG. 5 shows textured striking face 26 as a random multitude of dots, FIG. 8 shows that the uniformly textured surface finish of striking face 26 when seen in enlarged plan view, is comprised of an array of tightly and uniformly packed circles representing indented dimples 50. FIGS. 9 and 10 show that when seen in vertical section, dimples 50 preferably have a diameter “d” of about 0.008 inch, and, they are comprised of semi-circles or hemisputter headeres 52 indented to a depth of from about 0.0010 inch to about 0.0020 inch into the surface of striking face 26. Preferably, dimples 50 are uniformly spaced from each other in a quantity or density of about 10,000 per square inch.

Generally, that which is referenced and described above applies to golf putter heads covered by the disclosure, regardless of whether the golf putter head is a mallet-type, blade-type or other type of golf putter.

For example, FIGS. 11 through 15 show an embodiment of a blade-type golf putter head of the disclosure. More particularly, FIG. 11 shows a blade-type golf putter head 10′ that has basically the same features as were described above in connection with the disclosure of mallet-type golf putter head 10. Features of the mallet-type putter head 10 and of blade-type putter head 10′ that are basically the same are indicated by the same reference number, while features that are slightly different are indicated by the same reference number with a prime. Main features of putter heads 10 and 10′ that are basically the same include a one-piece body 12, an upstanding wall 14 having a front portion 20 comprised of a contact wall 24 in turn having a textured front striking face 26, and a downwardly disposed unbounded through-cavity 30 behind, preferably directly behind, striking face 26, through-cavity 30 being transverse to longitudinal axis LA and extending from and through respective top and bottom surfaces 16,18 of upstanding wall 14, and through-cavity 30 having a front wall 32 that forms, i.e., is the same as, rear wall surface 28 of contact wall 24. Other main features of embodiments of golf putter heads of the disclosure, though not described in detail above, include the material of which the one-piece bodies of the putter heads are made, and the textured, dimpled finish of striking face 26.

Minor differences between mallet type golf putter head 10 and blade-type putter head 10′ relate, for example, in blade-type putter head 10′ to rear portion 22′ of upstanding wall 14′. Whereas in mallet-type golf putter head 10, rear portion 22 of upstanding wall 14 has a substantially flat rear portion, e.g., rim 22, that is generally parallel to front striking face 26, in the blade-type golf putter head 10′, rear portion 22′ is arcuate, that is, convex toward the front F of putter head 10′ when it is seen in top plan view. Also, whereas in mallet-type golf putter head 10, rearwardly extending surface 48 of the tail or shelf, hereafter referred to as the shelf, extends quite a distance to the rear of upstanding wall 14 and finishes in an arcuate sweep behind upstanding wall 14 to provide a heavy feel to the mallet type putter head, in blade-type golf putter head 10′, rearwardly extending surface 48′ of the shorter shelf extends only to the rear of rounded toe T and heel H surfaces to the rear of upstanding wall 14′. For example, whereas the rearmost point of putter head 10, the shelf can be 1.900 inch, the shelf of putter head 10′ is shorter and can be 1.375 inch. A consequence of the shorter length of rearwardly extending surface 48′ of the shelf is that alignment groove 40 is shorter in blade-type putter head 10′.

FIGS. 14 and 15 respectively are side elevational views of the toe T and heel H ends of golf putter head 10′, and the front striking face 25 of upstanding wall 14 of one-piece body 12.

In FIGS. 16-22, there is shown a second embodiment of a mallet type putter head of the present disclosure. More particularly, these Figures show a mallet style putter head generally designated 100, comprised of many of the features and elements present in the first embodiment of mallet type putter head 10. Features and elements that are common to or substantially the same in each of the mallet type putter head embodiments 10 and 100, whether or not mentioned with respect to embodiment 100, are understood and considered to have the same reference numbers. Features that are different or in addition in embodiment 100 are given a 3 digit 100 to 199 series reference number.

Second mallet style embodiment 100 is considered the preferred embodiment of the mallet type putter heads of the disclosure.

FIG. 16 is a top front perspective view, and FIG. 17 is a top left rear perspective view of mallet type golf putter head 100. These Figures show that rear portion 122 of upstanding wall 114 includes a central portion cp that is located behind central portion 36 of through-cavity 30, and includes a convexly shaped portion 160 that extends in a rearward direction generally along and to each side of longitudinal axis LA toward rear R of putter head 100. Central portion cp of upstanding wall 114 and central portion CP of putter head 100′ includes a mass of the stainless steel material of which body 112 is made, to thereby provide putter head 100 with a centrally located high moment of inertia. The mass of central portion cp of upstanding wall 114 includes convexly shaped portion 160 of upstanding wall 114. The mass of central portion CP of putter head 100′ includes both central portion cp of upstanding wall 114 and spherical mound 170.

FIGS. 16, 17 and FIG. 18, a top plan view of putter head 100, show that rear portion 122 of top surface 116 of upstanding wall 114, and upstanding wall 114 itself preferably have an undulating configuration that extends in a direction generally along transverse axis TA. The undulating configuration preferably is comprised of opposed, rearwardly extending convexly shaped heel H and toe T wall surface portions 162,164 which respectively merge into adjacent, more centrally located, forwardly facing concavely shaped pocket wall surface portions 166, 168, each of which respectively merge into centrally located rearwardly extending convexly shaped portion 160 of central portion cp.

The rearwardly extending mass of stainless steel material of central portion cp of upstanding wall 114 and central portion CP of putter head 100′ need not include, but preferably do include a rearwardly extending geometrically shaped portion which need not be, but preferably is an integral, i.e., all one-piece, extension of upstanding wall 114. As shown, the rearwardly extending geometrically shaped portion preferably is at least a portion or segment of a sphere, here shown as a spherical mound generally designated 170. FIG. 21 shows a vertical cross section through central portion cp of upstanding wall 114 and through central portion CP of putter head 100′, including through rearwardly extending spherical mound 170. It is contemplated to be within the scope of this disclosure that the rearwardly extending geometrically shaped portion can be selected from the group consisting of circular, oblong, cylindrical, rectilinear, triangular, or other suitable geometric shapes.

Referring to FIGS. 16 through 21, and to FIG. 18A, preferred dimensions of features of putter head 100 include:

“a”, the radius of curvature of convexly shaped heel H and toe T wall surface portions 162,164, is 0.300″ (meaning three hundred thousandths of an inch);

“b”, the radius of curvature of forwardly facing concavely shaped pocket wall surface portions 166, 168, is 0.400″;

“c”, referring also to FIG. 18A, the best fit radius of curvature of rearwardly extending convexly shaped central portion cp, is formed by two separate intersecting radii, “r” each of which is 2.346″, the individual radii “r’ originating a distance “o” that is 1.486 forward of the top edge of striking face 26, and being spaced 0.634″ to opposite sides “os” of longitudinal axis LA;

“c”, referring to FIG. 18A, the distance from the topmost edge of striking face 26 rearward to the center rearmost point on the convex radius of the respective heel H and toe T, (that is, the front to rear longitudinal depth of the top surface 116 of upstanding wall 114), is 0.898″;

“cc”, referring to FIG. 18A, the distance from the topmost edge of striking face 26 rearward to the center rearmost point on the convex best fit radius of curvature of central portion 160, is 0.780″;

“ccc”, referring to FIG. 18A, the distance from the topmost edge of striking face 26 rearward to the center of the forwardly extending concave radii curvature of pocket wall surface 166, 168, is 0.414″;

“CP”, the distance from the center of the radius of curvature “b” of pocket wall surface 166 to the center of the radius of curvature “b” of pocket wall surface 168, extended to the front F and to the rear R of putter head 100, that is, the transverse width of central portion CP of putter head 100, is 1.8652″;

“d”, the radius of curvature of spherical mound 170 is 0.8425″ (see FIG. 21);

“e”, the radius of curvature of concave fillet 172 above spherical mound 170, where its spherical surface meets top surface 116 of central portion cp of upstanding wall 114, and where its spherical surface meets pocket wall surface portions 166,168, is 0.400″; and

“f”, the radius of curvature of concave fillet 174 at and tracing along the junction of the base of upstanding wall 114, below convexly shaped heel H and toe T wall surface portions 162, 164, below concavely shaped pocket wall surface portions 166,168, and below spherical mound 170 where its spherical surface and the aforementioned other wall surface portions meet the rearwardly extending top surface 148 of shelf S, is 0.250″.

FIG. 19, a front elevational view of putter head 100′ of FIG. 18, shows that putter head 100′ preferably has a flat top surface 116 and a slightly arcuate bottom surface 18. FIG. 19 also shows sweet spot SS and a circular dashed line that refers to FIG. 8, which in turn shows that striking face 26 has a uniformly textured finish comprised of indented dimples 50.

FIG. 20, a rear elevational view of putter head 100 of FIG. 18, shows convexly shaped heel H and toe T wall surface portions 162, 164, concavely shaped pocket wall surface portions 166,168, convexly shaped central portion cp of upstanding wall 114, convexly shaped spherical mound 170, concave fillet 172 generally above spherical mound 170, and concave fillet 174 along the base of upstanding wall 114, joining spherical mound 170, and the above mentioned wall surface portions with the top surface 148 of rearwardly extending shelf S.

FIG. 20A, a bottom plan view of putter head 100 of FIG. 18, and FIG. 20B, a rear perspective view of the bottom of putter head 100, show that through-cavity 30 extends all the way through upstanding wall 114 (not shown) from and through its top surface 116 (not shown) to and through its bottom surface 18. FIGS. 20A and 20B also show upwardly angled bottom surface portion 118 of rearwardly extending shelf S of bottom wall 18.

FIG. 20C, a left side elevational view of putter head 100 of FIG. 18, and FIG. 20D, a right side elevational view of putter head 100 of FIG. 18, show the spherical profile of spherical mound 170 and the concave profile of fillet 174 joining the profile of the spherical mound 170 to top surface 148 of rearwardly extending shelf S. These Figures also show rearwardly extending upwardly angled bottom surface portion 118 of bottom wall 18.

Referring to FIG. 21, a vertical sectional view as would be seen along line 21-21 along longitudinal axis LA and through sweet spot SS of FIG. 19, shows that preferred dimensions of features of putter head 100 of the disclosure include:

“d”, the radius of curvature of spherical mound 170, is 0.8425″;

“g”, the distance from top surface 116 of upstanding wall 114 to the radial center point of spherical mound 170, is 0.8435″;

“h”, the thickness of contact wall 24 at sweet spot SS, is 0.750″;

“tc”, the width of through-cavity 30 at sweet spot SS, is 0.080″;

“j”, the distance from striking face 26 to the radial center point of spherical mound 170, is 0.6150″;

“k”, the distance from striking face 26 to the rearward-most point of central portion cp, (also considered the front to rear width of upstanding wall 114), is 0.9500″; [is this the same dimension as bottom wall 18?]

“l”, the distance from striking face 26 to the rear edge of shelf S of bottom wall 18, is 1.9000″; and

“m”, the distance from top surface 116 of upstanding wall 114 to top surface 148 of shelf S of bottom wall 18, is 0.7000″.

FIGS. 18 and 21 show that the mass that comprises central portion cp of upstanding wall 114 between its top surface 116 and bottom wall 18 and that comprises the integral mass of spherical mound 170, are centrally located within central portion CP of putter head 100 directly behind through-cavity 30 and contact wall 24. This configuration provides one-piece putter head 100 of the disclosure with balance and a high moment of inertia that resists twisting of the putter head during the putting stroke.

FIG. 22 is a nearly horizontal section taken along line 22-22 through putter head 100 of FIG. 21. In FIG. 21, the section line is shown tilted downward about 3 degrees to provide the reader with a sectional view straight down into and completely through through-cavity 30. FIG. 22 shows the upper portion of spherical mound 170 in section, and a lower portion of the spherical mound 170 and fillet 174 each in top plan view. The reference letter “n” refers to the preferred breadth of sweet spot SS, and is 0.5000″. The reference letter “o” represents the distance between the center points of the terminal ends of through through-cavity 30 and is 2.300″. The reference letter “p” near the terminal ends of through-cavity 30 represents the width of through-cavity 30 at those points and is “0.132”.

FIG. 23 is a horizontal section taken along line 23-23 through putter head 100 of FIG. 21. More particularly, the section is taken through or along the bases of spherical mound 170, concave pocket wall surfaces 166, 168, and convex wall surfaces 162 and 164, with fillet 174 being visible along the base of spherical wall 170 and the base of the aforementioned wall surfaces.

FIGS. 24 through 29 show a second embodiment of a blade type putter head of the disclosure, generally referred to as 100′. The Figures show that blade type putter head 100′ is basically the same as mallet type putter head 100, except that blade type putter head 100′ preferably does not have a rearwardly extending shelf S. Accordingly, except for not having a rearwardly extending shelf S, putter head 100′ has basically the same structural features and reference numbers as mallet type putter head 100. With respect to the dimensions of blade putter head 100′, they can be any suitable dimensions. For example, they can be basically the same as those of mallet putter head 100′, or smaller.

Referring mainly to FIGS. 24 through 26, 28B and FIG. 29, these Figures show that rear portion 122 of upstanding wall 114, like mallet type putter head 100, preferably has a rearward undulating configuration that extends in a direction generally along transverse axis TA. The undulating configuration preferably is comprised of opposed, rearwardly extending convexly shaped heel H and toe T wall surface portions 162,164 which respectively merge into adjacent, more centrally located, forwardly facing concavely shaped pocket wall surface portions 166, 168, each of which respectively merge into centrally located rearwardly extending convexly shaped central portion cp.

As is the case with mallet type putter head 100, blade type putter head 100′ preferably includes a centrally located rearwardly extending integral mass of putter head stainless steel material of central portion cp of upstanding wall 114. The centrally located rearwardly extending mass of material preferably also includes a rearwardly extending geometrical shape which need not be, but preferably is at least a portion or segment of a preferably solid sphere, here referred to as spherical mound 170 which is located within central portion CP of putter head 100′.

Referring to FIG. 26, preferred dimensions of features of putter head 100′ can include:

“a”, the radius of curvature of convexly shaped heel H and toe T wall surface portions 162, 164, can be 0.300″;

“b”, the radius of curvature of forwardly facing concavely shaped pocket wall surface portions 166, 168, can be 0.300″;

“c”, (referring also to FIG. 18A), the best fit radius of curvature of rearwardly extending convexly shaped central portion cp, can be formed by two separate intersecting radii, “r”, each of which can be 2.346″, the individual radii “r’ originating a distance “o” that can be 1.486″ forward of the top edge of striking face 26, and can be 0.634″ to opposite sides “os” of longitudinal axis LA;

“CP”, the distance from the center of the radius of curvature “b” of pocket wall surface 166 to the center of the radius of curvature “b” of pocket wall surface 168, extended to the front F and to the rear R of putter head 100, that is, the transverse width of central portion CP of putter head 100, can be 2.0571″;

“d”, the radius of curvature of spherical mound 170 can be 0.8300″;

“e”, the radius of curvature of concave fillet 172 above spherical mound 170, where its spherical surface meets top surface 116 of central portion cp of upstanding wall 114, and where its spherical surface meets pocket wall surface portions 166, 168, can be 0.250″;

“f”, referring to FIG. 25, the radius of curvature of concave fillet 174′ at and tracing along the junction of the base of upstanding wall 114, below convexly shaped heel H and toe T wall surface portions 162,164, below concavely shaped pocket wall surface portions 166,168, and below spherical mound 170 where its spherical surface and the aforementioned other wall surface portions meet the rearwardly extending edge of upwardly angled bottom surface 18′, can be 0.250″; and

“fp”, refers to the front portion 20 of upstanding wall 114 and is the distance from striking face 26 rearward behind through-cavity 30 to a transaxial line running parallel to or corresponding to transverse axis TA, which distance can be 0.3650

FIG. 27 is a front elevational view, and FIG. 28 is a rear elevational view, of putter head 100′ of FIG. 26. FIG. 28A is a bottom plan view, and FIG. 28B is a bottom rear perspective view, of putter head 100′ of FIG. 26. FIG. 28B shows fillet 174′ joining the surface of spherical mound 170 with edge 150 of angled portion 118′ of bottom wall 18.

FIG. 29 is a vertical sectional view as would be seen along line 29-29 of FIG. 27, through central portion cp of upstanding wall 114, and through central portion CP of putter head 100′, including through sweet spot SS and through rearwardly extending solid spherical mound 170. As shown in FIG. 29, and as also shown in FIGS. 25, 26, 28, 28B and 29, spherical mound 170 is bounded about its upper periphery by an elongated fillet 172 and along its lower extent or edge by elongated fillet 174′ which joins the lower extent of spherical mound 170 to the rear edge 150 of upwardly angled bottom wall portion 118′.

FIG. 29 shows that preferred dimensions of features of putter head 100′ of the disclosure can include:

“d′”, the radius of curvature of spherical mound 170, is 0.8425″;

“g′”, the distance from top surface 116 of upstanding wall 114 to the radial center point of spherical mound 170, is 0.8435″;

“h”, the thickness of contact wall 24 at sweet spot SS, is 0.750″;

“tc”, the width or gap of through-cavity 30 at sweet spot SS, is 0.080″;

“j′”, the distance from striking face 26 to the radial center point of spherical mound 170, is 0.3650″;

“k′”, the distance from the lower portion of striking face 26 to the rearward-most point of central portion cp of upstanding wall 114, is 0.9500″ (This is also considered to be the front to rear width of upstanding wall 114);

“I′”, the distance from the lower portion of striking face 26 to the rear edge of spherical mound 170, is 1.1950″; and

“ba”, the angle measured from bottom surface 18′ to upwardly extending surface 118′, is 15 degrees.

The shown and preferred segment of spherical mound 170 of putter head embodiments 100, 100′ preferably is the size of a segment of a golf ball.

The golf putter head of the disclosure permits a variety of shafting styles. The golf putter heads of the disclosure can be attached or secured by suitable conventional means to suitable conventional golf club shafts. Although golf putter heads of the disclosure, including those designated 10, 10′, 100 and 100′ are each shown having structure, e.g. a straight hole 60 at heel H for receiving the mounting end of a suitable shaft (not shown), it is contemplated that the putter heads alternatively can be center shafted. Holes 60 can be straight, e.g. (orthogonal to the transverse axis or longitudinal axis) or disposed at an angle adjacent the center of the head (not shown). The shafts can be straight or bent.

Regardless of shafting variants and head style chosen, features which can be selected to be common to, or used individually in or in suitable and various combinations in the golf putter heads of the disclosure include unbounded through-cavity 30, it preferably being a thin cavity and preferably elliptical in shape, formed, preferably machined, in one-piece body 12, adjacent or behind, preferably directly behind, striking face 26, a machine-textured striking face 26 having a texture in the form of an array of precision machined uniform hemispherical dimples therein, the one-piece body preferably being converted, i. e., machined or milled, from a solid bar of a heat treatable stainless steel alloy having a hardness of from about 25 to about 32 on the Rockwell C-Scale, and heat treated and tempered to a high hardness of from about 48 to about 52, more preferably from about 44 to about 47, on the Rockwell C-Scale, the combination of a very hard, i.e. highly hardened, one-piece putter head having the machined textured face on a contact wall feature partly formed by the front wall of an elliptical through-cavity preferably directly behind the contact wall, provides golf putter heads of the disclosure that meet one or more of objectives of the disclosure.

With respect to the feature of a “contact wall”, the term “contact wall” herein means the portion of front portion 20 of upstanding wall 14, or 114 that extends between front striking face 26 and rear wall surface 28. Preferably the thickness of the contact wall at sweet spot SS, and adjacent it for about 0.250 inch to either side of it, is from about 0.030 inch to about 0.080 inch, preferably from about 0.060 inch to about 0.080 inch, more preferably from about 0.065 inch to about 0.075 inch, and most preferably about 0.075 inch. Sweet spot SS is at the center of the length of striking face 26 and is aligned with alignment groove 40. Preferably, the thickness of the contact wall at sweet spot SS and about 0.250 inch to either side of it is uniform and the surfaces of front striking face 26 and rear wall surface 28 are parallel to each other and flat. Adjacent the end portions 35 of through-cavity 30, the thickness of the contact wall preferably is from about 0.100 inch to about 0.180 inch, more preferably from about 0.150 inch to about 0.180 inch and most preferably from about 0.160 inch to about 0.170 inch. Preferably, the thickness of the contact wall increases gradually at a non-linear rate as the wall extends along its elliptical path from the flat portion adjacent sweet spot SS toward end portions 35 of through-cavity 30.

Another feature which can be and preferably is employed in the putter heads of the disclosure is an upstanding wall that has a rear portion that includes a central portion cp, which in turn includes a mass of putter head body material that extends rearwardly generally along and preferably to each side of the longitudinal axis of the putter head. The central portion of the upstanding wall that extends rearwardly can have a convex shape. The central portion of the upstanding wall that extends rearwardly can include an integral geometrically shaped portion which can be or include a portion or segment of a sphere, for example, a spherical mound 170. The mass of the rearwardly extending geometrically shaped portion or sphere is included within the central portion CP of the putter head of the disclosure. This mass provides balance to the putter head and helps provide a high moment of inertia to the putter head. This helps prevent twisting of the putter head during the putting stroke.

Embodiments of the disclosure include methods of making the disclosed one-piece, preferably one-material, golf putter heads 10, 10′, 100 and 100′. The embodiments of the methods of the disclosure apply to making putter heads of mallet, blade or other type designs. The methods include providing a solid bar of heat treatable stainless steel alloy (not shown) that is to be formed or converted, e.g., machined or milled, into one-piece putter head 10, 10′, 100 and 100′. The solid bar of heat treatable stainless steel alloy that is provided can have a hardness of from about 25 to about 32 on the Rockwell C-Scale. The solid bar is converted, e.g., milled or machined, to nearly the desired final form of the putter head, that is, to a form that includes a preliminary or temporary front striking surface that is to become or be formed into textured striking face, e.g. 26. The nearly desired final putter form does not include a through-cavity or a textured striking face. The forming of the putter head prior to heat treating preferably is by use of Computerized Numerically Controlled machine tools.

The nearly desired final putter form is heat treated to increase its metal hardness and temper it to a Rockwell hardness of from about 48 to about 52, preferably from about 44 to about 47 on the Rockwell C-Scale. A preferred heat treated stainless steel is known and sold as “17-4 ph”, or less preferably a 440 C Stainless Steel. Next, a shaped, unbounded through-cavity 30 is formed behind, preferably directly behind, the preliminary front striking surface. The forming of through-cavity 30 preferably is effected by use of a Wire Electric Discharge Machining Process. The forming of through-cavity 30 can be effected by giving the cavity an elliptical shape, or the general shape of an open umbrella that has a convex outer surface that is directed toward the preliminary front surface. The forming of through-cavity 30 also can be effected to provide the through-cavity with the general shape of a bow having a convex surface that is directed toward the preliminary front surface, and whose ends are bowed away from the preliminary front surface.

The preliminary front surface of the nearly desired final putter is formed into a textured striking face 26 by machining into the preliminary front surface an array or series of uniform precision dimples and uniform lands between the dimples. Preferably, the forming of the textured striking face is effected to provide an array of uniform precision dimples in the form of indented hemispheres having a diameter of preferably from about 0.005 inch to about 0.012 inch, more preferably from about 0.007 inch to about 0.010 inch, and most preferably about 0.008 inch. The forming of the textured striking face preferably is effected to provide an array of uniform precision dimples in the form of indented hemispheres having a depth of about 0.001 inch to about 0.002 inch. The forming of the textured striking face is effected to provide the striking face with an array of uniform dimples uniformly spaced from each other in a quantity or density of about 10,000 dimples per square inch.

Through-cavity 30 preferably is formed parallel to the preliminary front surface or to textured striking face 26. In a preferred embodiment, textured striking face 26 is formed to be substantially flat and to have a loft angle La of 3 or 4 degrees, preferably 3 degrees, relative to bottom wall 18 of golf putter head 10, 10′, 100 or 100″. The textured striking face preferably is effected by an Electric Discharge Machining Ram Process.

The present disclosure having thus been described with particular reference to embodiments thereof, it will be discerned that various changes may be made therein without departing from the spirit or scope of the present disclosure as described herein.

Claims

1. A golf putter head for attachment to a golf club shaft, comprising:

a one piece body that is made of a stainless steel material that has a hardness of from about 44 to about 52 on the Rockwell C-Scale, the body including a front and a rear, a front-to-rear longitudinal axis and a transverse axis, a heel and a toe oppositely disposed on a transverse axis, at least one of the heel and toe having structure for attachment to a golf club shaft, and, an upstanding wall whose length extends transverse to the longitudinal axis and whose width extends along a longitudinal axis, the upstanding wall having a top surface, and a bottom surface, a front portion and a rear portion, the front portion of the upstanding wall extending generally between the heel and toe and being comprised of a contact wall having a front striking face and a rear wall surface, and a downwardly disposed unbounded through-cavity, the through-cavity being directly behind the striking face, transverse to the longitudinal axis and extending from and through the top and bottom surfaces of the upstanding wall, the through-cavity having a front wall surface that forms the rear wall surface of the contact wall.

2. The putter head of claim 1, wherein the striking face has a uniform texture comprised of an array of dimples in the form of indented hemispheres.

3. The putter head of claim 1, wherein the body is comprised of heat treated stainless steel.

4. The putter of head claim 1, wherein the through-cavity has an elliptical shape when seen in top plan view or in horizontal section.

5. The putter head of claim 1, wherein the striking face includes a sweet spot, the through-cavity also has a rear wall surface, the front and rear wall surfaces of the through-cavity define a central portion of the through-cavity, and the spacing between the front and rear wall surfaces at the central portion of the through-cavity behind the sweet spot is in the range between about 0.070″ to about 0.090″.

6. The putter head of claim 1, wherein the striking face is substantially flat and the through-cavity is generally parallel to the front striking face.

7. The putter head of claim 1, wherein the putter head is either mallet type or blade type.

8. The putter head of claim 1, wherein the front striking face has a sweet spot at the center of the length of the front striking face, and wherein the thickness of the contact wall that extends generally along the longitudinal axis between the front striking face and the rear wall surface of the contact wall at the sweet spot and adjacent it to either side of the sweet spot, is from about 0.060 inch to about 0.080 inch.

9. The putter head of claim 1, wherein the thickness of the contact wall between the front striking face and the rear wall surface of the contact wall at the sweet spot and adjacent it for about 0.250 inch to either side of the sweet spot is uniform.

10. The putter head of claim 1, wherein the rear portion of the upstanding wall includes a central portion that includes a mass of the body material that extends rearwardly generally along and to each side of the longitudinal axis.

11. The golf putter head of claim 10, wherein the central portion of the upstanding wall that extends rearwardly has a convex.

12. The golf putter head of claim 11, wherein the rear portion of the upstanding wall, when seen in top plan view, has a rearwardly facing undulating configuration that extends in a direction generally along or aside the transverse axis, the undulating configuration being comprised of opposed rearwardly extending convexly shaped heel and toe wall surface portions, the heel and toe wall surface portions merging into adjacent, more centrally located forwardly facing concavely shaped pocket wall surface portions, and the respective pocket wall surface portions merging into a rearwardly extending convexly shaped central portion of the putter head.

13. The putter head of claim 10, wherein the rearwardly extending mass of body material of the central portion of the upstanding wall includes an integral rearwardly extending geometrically shaped portion.

14. The putter head of claim 13, wherein the geometrically shaped portion includes a portion of a sphere.

15. The putter head of claim 1, wherein the stainless steel material is at least one selected from the group consisting of heat treated 17-4 ph stainless steel, a 400 series stainless steel and a 400 C series stainless steel.

16. A method of making a one-piece golf putter head of one material, which comprises:

providing a solid bar of heat treatable stainless steel alloy that is to be formed into the putter head;

converting the solid bar to nearly the desired final form of the putter head, except for the formation of a through-cavity and a textured striking face, the nearly desired final putter form including a preliminary front striking surface that is to become the textured striking face;

heat treating the converted nearly desired final putter form to increase its metal hardness to a Rockwell hardness tempered to from about 44 to about 52 on the Rockwell C-Scale;

forming a shaped through-cavity directly behind the preliminary front surface; and

forming the preliminary front surface into a textured striking face, by machining into the preliminary front surface a series of uniform precision dimples and uniform lands between the dimples.

17. The method of claim 16, wherein the forming of the through-cavity includes forming the cavity in an elliptical shape.

18. The method of claim 16, wherein the forming of the textured striking face is effected to provide an array of uniform dimples in the form of indented hemispheres having a diameter of about 0.005 inch to about 0.012 inch.

19. The method of claim 16, wherein the through-cavity is formed parallel to the textured striking face.

20. The method of claim 16, wherein the forming of the through cavity is effected by a Wire Electric Discharge Machining Process.