Finger grip insert providing size compliance

A finger grip insert has a tubular resilient body with an outer wall having at least one recessed section with a concave shape. The center of the tube is shaped to accommodate a human finger. The deformable insert fits into a bowling ball finger hole, and has two sections. The first section extends from the outer surface of the bowling ball to the bowler's fingertip when the finger is placed into the insert. The outer wall of the first section has one or more recesses formed that extend only partially through the tubular body to permit the insert to deform within the finger hole in the area of the recess, responsive to pressure from the bowler's finger. The second section extends from the bowler's fingertip to the end of the insert, and provides a surface to attach the insert to the bowling ball finger hole.

TECHNICAL FIELD 
This invention generally relates to a finger grip insert, and more 
particularly, to an insert for a bowling ball finger hole. 
BACKGROUND 
The sport of bowling is well known, and played by millions. We are 
concerned here with the bowling ball, which is large and heavy, and of a 
diameter that makes it virtually impossible to be safely handled with one 
hand. In order to propel the ball with one hand, holes are drilled into 
the ball for insertion of the fingers of the bowler's preferred hand. Most 
often, three such holes, for a thumb and two fingers, are precisely 
drilled, defining a triangle on the surface of the ball. Using them, the 
bowler can propel the ball down the alley in a fluid, one-handed motion 
toward the bowling pins. 
The diameters of the drilled holes are chosen to accommodate the individual 
user. Since each person has differing finger sizes, bowling balls are 
typically custom fit for optimum efficacy. This presents a less than ideal 
solution because the owner of the ball will find that his fingers will not 
always fit the holes as well as he might like, due to changes in finger 
size from swelling, injury, or weight gain or loss. Moreover, other people 
will not be able to use that ball as the holes will be the wrong size for 
their fingers. Finger holes are typically drilled in increments of 1/32 
inch, and since human fingers are not formed in 1/32 inch increments, this 
presents an undesirable compromise. 
The situation is most acute for the novice bowler who, typically, does not 
own a ball, but `borrows` one from the bowling alley. The novice must 
search through of the many `loaners` available at the establishment to 
hopefully find one that gives the best fit. Compromise in this situation 
is unavoidable. 
Further, since the bowling ball is by necessity made from a hard material, 
frequent bowling often results in sore fingers, chafing, or even blisters 
and calluses. Particularly strong bowlers, known in the vernacular as 
`crankers`, commonly release the ball with a severe rotation of the wrist 
and fingers to impart spin to the ball and create a curved path for the 
ball to impact the pins. This type of ball release requires the user's 
fingers to withstand a significant amount of side pressure, creating 
fatigue and discomfort. 
Prior art solution have attempted to solve these problems by providing many 
types of finger hole inserts for bowling balls. Typical of such inserts 
are those disclosed in U.S. Pat. Nos. 4,968,033; 4,289,312; 5,176,378; 
4,778,178; 2,842,367; 4,773,645; and 4,561,654. One solution is posed in 
U.S. Pat. No. 4,289,312 which discloses a finger hole insert made from 
resilient vinyl. During the delivery of the ball, the insert is said to 
compress under the bowler's finger pressure. However, those skilled in the 
art will appreciate that elastomers such as vinyls and rubbers do not 
compress, but merely displace, and inserts of this type have minimal, if 
any compliance to accommodate varying finger sizes. The variety of ideas 
found in these patents attest to the need for a solution to the problem. 
Most bowlers today continue to suffer from poor finger fit, and as a 
consequence, compromise the optimum situation. 
Clearly, the problems illustrated above would find a solution in a bowling 
ball having holes whose diameters could be easily adjusted, and whose 
holes could provide compliance. The present invention provides such a 
solution. 
SUMMARY OF THE INVENTION 
Briefly, according to the invention, there is provided a finger grip insert 
comprising a tubular resilient body. An outer wall of the insert has at 
least one recessed section having a concave shape. The inner wall is 
shaped to accommodate a human finger. 
In another embodiment of the invention, a deformable insert is provided for 
a finger hole of a bowling ball, and receives a bowler's finger. The 
insert is a resilient tubular body having two sections. The first section 
extends from the outer surface of the bowling ball to the bowler's 
fingertip when the finger is placed into the insert. The outer wall of the 
first section has one or more recesses formed therein, that extend only 
partially through the tubular body so as to permit the insert to deform 
within the finger hole in the area of the recess, responsive to pressure 
from the bowler's finger. The second section extends from the bowler's 
fingertip, and provides a surface to attach the insert to the bowling ball 
finger hole. 
In still another embodiment, a bowling ball has at least two finger holes, 
and an insert in at least one of the finger holes. The insert is a 
resilient tubular member with a hollow core adapted to receive a bowler's 
finger. At least one recess is formed in the outer wall of the insert so 
that the insert is able to deform in response to pressure exerted on the 
resilient tubular member by the bowler's finger.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
While the specification concludes with claims defining the features of the 
invention that are regarded as novel, it is believed that the invention 
will be better understood from a consideration of the following 
description in conjunction with the drawing figures, in which like 
reference numerals are carried forward. 
Referring now to FIG. 1, a bowling ball 1 is shown for purposes of 
illustration to have three finger holes (2, 3, and 4) drilled partway into 
the interior. Those skilled in the art of bowling will appreciate that some 
balls have fewer than three holes, for example, a particular bowler may 
elect to only use two holes. Holes 2 and 3 are typically used for the 
fingers, and hole 4 is generally a thumb hole. for present purposes, the 
thumb is to be construed as a finger, that is, the insert of the instant 
invention is equally adaptable for use with fingers or thumb. A resilient, 
elastomeric insert 5 resides in the finger holes 2-4 such that the outer 
edge of the insert is substantially flush with the surface of the ball. 
Again, although the figure depicts a bowling ball with inserts in each of 
the finger holes, one, two or three inserts may be used, in response to 
the needs and wishes of the individual bowler, and still fall within the 
spirit and scope of the invention. Referring now to FIG. 2, an isometric 
view of the insert reveals the novel structure of the instant invention. 
In this preferred embodiment of the invention, the insert 5 is formed of a 
resilient, elastomeric material such as silicone rubber, thermoplastic 
elastomer, synthetic rubber, vinyl, urethanes, neoprene, or other similar 
materials. The resilient material is preferably a solid material, but may 
also be any number of foam-type materials, typically containing small 
cavities of a gas. In any event, resilient materials having durometers 
between Shore A 20 and Shore A 80 may be useful, with a Shore A durometer 
of about 60 being preferred. In practice, the insert 5 is made by, for 
example, injection molding the elastomeric material into a mold cavity. 
Injection molding and other comparable techniques such as potting, 
casting, RIM molding, etc. are well known, and will be readily understood 
by those skilled in the art. 
The insert 5 is a generally tubular member with an outer wall 6 and an 
inner wall 7. A tube being generally defined as a hollow, elongated 
cylinder, the tubular member has an aperture 8 down the middle. The 
aperture 8 generally extends the full length of the insert, but may be 
truncated if so desired, leaving a tube with a closed end at the bottom. 
The aperture 8 is shown to be substantially parallel to and in line with a 
central axis 9 of the tube, coaxial with the outer wall 6, but may also be 
off-center or skewed. Generally speaking, the axis of the aperture will be 
coaxial with the axis of the insert, to aid in manufacturing and to aid in 
fitting the insert into the ball. A series of recesses 10 are formed in 
the outer wall and disposed longitudinally around the periphery. FIG. 2 
shows the recesses 10 in the shape of flutes extending partially down the 
length of the tube on the outer wall. These flutes extend in a direction 
parallel to the central axis 9, longitudinal to the insert 5. They also 
are disposed radially around the circumference of the insert. FIG. 3 shows 
details of one arrangement of the recesses 10 disposed radially around the 
insert 5. Flutes or recesses should cover between about 90 degrees and 
about 360 degrees of the outer wall, with a range of between 135 to 270 
degrees being the optimum. In the preferred embodiment of the invention, 
the flutes cover about 225 degrees of the outer wall, leaving the 
remaining 135 degrees of the wall essentially smooth. Various bowlers 
might need other types or configurations of the flutes or recesses, to 
provide a custom `feel` for bowlers of differing skill levels. For 
example, to create a stiffer insert without changing the type of resilient 
material, fewer flutes would be used. Some bowlers might want a very 
`forgiving` insert, thereby necessitating more flutes, or flutes around a 
larger portion of the periphery of the insert. 
Note that the recesses 10 only extend over a portion 12 of the insert. 
Normally, the length of this first portion is a function of the bowler's 
finger size. It has been found that this length is typically about two 
times the diameter of the bowler's finger, although this will vary 
somewhat amongst individuals. A more precise way to define the size of 
this portion would be in terms of the function served. As shown in FIG. 4, 
the recesses 10 should be formed in the area 12 of the insert coinciding 
with that portion receiving the bowler's finger 14. Normally, this would 
be defined by an area corresponding to that covered from the first knuckle 
16 to the distal end 18 of the finger, when the finger is placed in the 
insert up to the first knuckle. Creating recesses in the insert beyond 
this point, would still fall within the scope and spirit of the invention. 
The reader should also note that the end of the insert is substantially 
flush with the outer surface of the ball when it is placed into the finger 
hole, so as not to interfere with smooth rolling of the ball down the 
alley. 
Alternate embodiments of the invention employ recesses 10 extending the 
full length of the outer wall. Still further embodiments, FIG. 5 show the 
recesses 10 extending circumferentially around the outer wall 6 of the 
insert. FIG. 6 shows that the recesses 10 may also be a series of 
discontinuous cavities, of the same size and shape, or of differing size 
and shape, as dictated by the needs of the bowler. Various other types of 
recesses will, of course, come to mind, and should be interpreted to be 
within the spirit and scope of the present invention. 
The recesses in the outer wall form a suspension system that provides 
compliance to the insert. These recesses deform in response to pressure 
exerted by the bowler's finger against the inner wall of the insert. Since 
there is an empty space (the recess 10) between the rigid wall of the 
bowling ball finger hole and the resilient insert, the insert can deform 
to accommodate various finger shapes and sizes, and in response to finger 
pressure during delivery of the ball. This improved suspension system 
gives the bowler an additional "spring" action as the insert is deformed 
during delivery, and provides greater torque action or rotation of the 
ball as this energy is expelled during the ball release. Prior art 
solutions did not provide any compliance, but attempted to rely on the 
resilient properties of the soft insert. Those skilled in the art will 
appreciate that elastomers do not compress, but simply deform, and the 
earlier solutions did not provide any means for deformation, as is 
provided in the instant invention. The compliance provided by the insert 
aids in achieving a proper fit because it allows for variations in the 
"span" dimension of the ball. "Span" is the distance between the finger 
holes, and is typically fixed in the prior art configurations. The 
compliance provided by the instant invention also compensates for swelling 
of a bowler's fingers during the course of a series of games, and also 
helps to prevent abrasions and blisters on the bowler's fingers. 
The insert should be secured in the finger hole in order to keep the insert 
from popping out of the ball upon delivery. Typically, the insert is 
attached to the hole by means of an adhesive, for example, an epoxy, 
urethane, hot melt, cyanoacrylate, `super glue`, etc. A second portion 20 
of the insert, that portion extending from the fingertip 18 to the bottom 
22 of the insert, does not normally have the recesses that are found in 
the first portion. This area is useful for attaching the insert to the 
finger hole, and attachment is maximized by maximizing the surface area. 
To this end, recesses are generally avoided here, unless they are made to 
increase the adhesion to the hole, for example, dimples or `dovetailed` 
cavities to aid in mechanical bonding. By selecting the proper adhesive, 
the insert can be replaced when a change in the bowler's delivery style 
dictates, or when the insert has been worn out or broken. The insert is 
simply extracted, the remaining adhesive removed, and a new insert of the 
proper type is glued in. This allows more flexibility and a better custom 
fit for the ball, affording the bowling retailer (pro shop, etc) greater 
ease of customer fitting and reduced inventory, while providing an added 
value to the bowler. 
While the preferred embodiments of the invention have been illustrated and 
described, it will be clear that the invention is not so limited. Numerous 
modifications, changes, variations, substitutions and equivalents will 
occur to those skilled in the art without departing from the spirit and 
scope of the present invention as defined by the appended claims.