Dental floss tool

A dental floss tool including two simple snap together plastic parts which form a housing for fixedly mounting a reel of dental floss positioned to supply a length of floss to a support structure comprising two flexible slotted arms and a lock for securing the ends of the length of floss to maintain it under tension across the ends of the arms.

BACKGROUND OF THE INVENTION 
The invention relates generally to a dental floss tool and more 
particularly to a dental floss tool which is compact and provides tangle 
free storage of dental floss therein. 
Although a variety of dental floss tools exist in the marketplace, many of 
them suffer from a number of faults. Typical among them is that they 
require a great deal of dental floss to be used when employing the tool or 
that the tool is relatively complicated and expensive to manufacture. 
Typical among such prior art devices is that disclosed in U. S. Pat. No. 
4,004,599 to Rosenfeld which discloses a dental floss holder having a 
rotatable dental floss reel confined therein from which a length of dental 
floss may be extracted and extended over a pair of arms for use. One of 
the problems with such a device is that a rapid pull on the dental floss 
to unreel it from the spool can lead to jamming within the dental floss 
holder. In addition, the arms 21 and 22 are not flexible which makes it 
relatively difficult to tension the dental floss across the gap 26. Also, 
another problem is that while a button 25 is available on one of the arms 
22 to anchor one end of the dental floss, the other end of the dental 
floss remains relatively free to move being inhibited only by the 
frictional engagement of the toothed wheel 12. 
U.S. Pat. No. 3,378,017 to Stiles discloses a relatively complicated dental 
floss device which has been embodied in a commercial device. In that 
device a number of moving parts are employed and tension is maintained on 
the dental floss by trapping it between a pair of movable sections of the 
dental floss applicator. The device would appear to be quite expensive to 
manufacture. 
U.S. Pat. No. 1,171,177 to De L'Eau discloses a dental floss holder having 
a fixed supply of floss arranged in a coil 22. However, the device is 
quite complicated to manufacture as the moveable arms 11 and 12 are 
pivoted at a hinge mechanism 10. 
What is needed then is a dental floss tool or holder which is economical, 
easy to use and provides firm anchoring of the dental floss during use. 
SUMMARY OF THE INVENTION 
A dental floss tool is disclosed herein having a flattened cylindrically 
shaped floss storage housing with a spool of dental floss contained 
therein. The spool of dental floss is held fixed within the storage 
housing and has its central access aligned perpendicular to a flattened 
top and bottom of the housing. An aperture is formed in the center of the 
top of the housing through which dental floss may be removed. A pair of 
flexible arms are attached to a circular side wall of the housing opposite 
the fork. A lock button is formed integrally with the housing and defines 
a tapered circular groove with the cylindrical side wall thereof which 
comprises the floss lock. 
It is a principal object of the present invention to provide a dental floss 
tool from which stored dental floss may be withdrawn without jamming or 
tangling. 
It is another object of the present invention to provide a dental floss 
tool which allows the user to lock securely both ends of a length of 
dental floss to provide adequate tensioning thereto. 
It is another object of the instant invention to provide a dental floss 
tool which is compact, economical and easy to use. 
Other objects and advantages of the present invention will become obvious 
to one skilled in the art upon a perusal of the specification and claims 
in the light of the accompanying drawings

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings and especially to FIG. 1, a dental floss tool 
embodying the present invention and generally identified by numeral 10 is 
shown therein. The dental floss tool 10 includes a floss storage housing 
or container 12 having a fork 14 formed integrally therewith. A lock means 
or button 16 is mounted on the side of the housing 12. 
The floss storage housing 12 is a substantially right circular cylindrical 
housing consisting of a circular bottom wall 20 having a rounded, 
tapering, generally cylindrical side wall 22 formed integrally therewith. 
A cross shaped spool holding shaft 24 is formed integrally with the bottom 
wall 20 and is adapted to receive a spool of floss 30. A top cap 25 forms 
a top wall of the housing 12 and has an aperture 26 formed therein. The 
aperture 26 is positioned centrally over the spool holding shaft 24. 
The floss tool 10 is made up of two simple molded plastic parts, the first 
being a fork assembly 11 which includes the fork 14 and the top cap 25 of 
the floss storage housing 12 and the second being a cup assembly 13 which 
includes the bottom wall 20 and the side wall 22. As will be explained in 
detail below, these two parts, the fork assembly 11 and the cup assembly 
13 snap fit together to form the storage container for the floss and the 
means for conveniently supporting increments of the floss for use in 
cleaning the teeth. 
The spool of dental floss 30 comprising a spool body 31 and a quantity of 
dental floss 32 is force fitted over the spool holding shaft 24 and is 
thus fixed against rotation with respect to the housing 12. A floss 
starting end 34 is withdrawn from the length of floss 32 through the 
aperture 26. 
The bottom wall 20 and the side wall 22 of the floss housing 12 are molded 
as the unitary cup assembly 13 from high density polypropylene. The side 
wall 22 terminates in an outwardly extending flange or lip 40 which is 
adapted to engage other portions of the dental floss tool 10 in locking 
engagement. The spool shaft 24 consists of a shaft having a circular 
central section 44 formed integrally with the bottom wall 20 and extending 
perpendicularly therefrom. A plurality of vanes respectively numbered 46, 
48, 50 and 52 as shown in FIG. 9 extend from the central shaft 44 and are 
spaced at 90 degree intervals about the central shaft 44. The upper 
portions of the vanes are slightly tapered at their upper ends as shown at 
54 on the vanes in FIG. 10 in order to facilitate the assembly of the 
floss spool to the shaft 24. The vanes are at such a distance from the 
axis of shaft 24 that they cause the spool of floss 30 to deform slightly 
as it is forced onto the shaft 24 so that the spool body 31 is securely 
attached to the shaft 24. 
The lock means 16 is an integral part of the fork assembly 11 and is 
mounted on a support 60 which extends downwardly from one edge of the cap 
25 as shown in FIG. 3. The support 60 is received in a cut out or opening 
62 in the side wall 22 of the cup assembly 13. The opening 62 is defined 
by reinforcing walls on the cup assembly 13 including a first reinforcing 
upright vane 64 and a second reinforcing upright vane 66 both being formed 
integrally with the cup assembly 13. 
The top cap 25, the locking means 16, the support 60 and the fork 14 
comprise the fork assembly 11 which is composed of ABS plastic. The fork 
assembly 11 includes a first flexible arm 70 extending substantially 
coplanar with the top cap 25, The first flexible arm 70 is substantially 
rectangular in cross-section and defines a groove 72 on an upper surface 
thereof for guiding a length of dental floss therealong. The groove 72 is 
defined by an outer member 74 and an inner member 76. Likewise, a second 
flexible arm 80 has an inner member 82, an outer member 84 and a groove 86 
defined thereon. As best shown in the enlarged sectional view of FIG. 7, 
the outer member 84 extends higher above the groove 86 than does the inner 
member 82 so as to facilitate the user's insertion of the floss into the 
groove 86. Similarly, the outer member 74 on the arm 70 extends higher 
above the groove 72 than does the inner member 76. 
At the unsupported ends of the arms 70 and 80, the inner members 76 and 82 
extend slightly past the outer members 74 and 86 to terminate, 
respectively, at an ear 90 formed integrally with the inner member 76 and 
an ear 92 formed integrally with the inner member 82. Immediately adjacent 
the ears 90 and 92 are, respectively, a second ear member 84 adjacent ear 
member 90 and a second ear member 96 adjacent ear member 92, Ear members 
92 and 96 define a floss entrapment slot 98. Ear members 90 and 94 define 
a floss entrapment slot 100. In order to provide additional strength for 
the flexible arms 70 and 80, there is provided a curved web assembly 102 
formed integrally therebetween. 
The arms 70 and 80 terminate in an apex portion 106. Adjacent the apex 
portion 106 there is supported on the fork assembly 11 a metal floss 
cutter assembly 108 which is a generally U-shaped clip adapted to snap 
into assembled relation with the fork assembly 11. The metal floss cutter 
108 is composed of 310 or 410 stainless steel having a thickness of 0.010 
to 0.012 inches. The stainless steel is spring tempered. The cutter 108 
consists of a rounded tongue 110 formed integrally with a horizontal base 
112. A vertical wall 114 is formed integrally with the horizontal base 112 
and a spring leg 116 is formed integrally with the wall 114 extending 
generally parallel to the base 112. The cutter assembly 108 extends 
through an opening 119 in the cap 25 and is positioned adjacent to the 
aperture 26 as may be seen in FIG. 6. 
The spring leg 116 is formed with a locking tab or barb 120 which extends 
from the leg 116 upwardly toward the base 112. The locking tab 120 engages 
a recess in the lower surface of the cap 25. The recess includes a 
vertical wall 121 against which the locking tab 120 engages to prevent the 
cutter assembly 108 from being withdrawn to the right from the assembled 
positioned as shown in FIG. 8. It should be understood that the cutter 
assembly 108 is sufficiently resilient to permit the base 112 and the leg 
116 to be separated during assembly after which the locking tab 120 seats 
in the recess against the wall 121 to retain the cutter assembly 108 
rigidly secured to the cap 25 and the fork assembly 11. 
The top cap 25 includes a plurality of tapered shoulders 122, 124, 126 and 
128 which are adapted to engage in a snap fit relationship the lip 40 of 
the cup assembly 13. The tapered shoulders are supported on a downwardly 
extending peripheral flange 123 on the cap 25. Above each of the four 
shoulders 122, 124, 126 and 128 there are provided slots 125, 127, 129 and 
131 which facilitate the molding of the fork assembly 11. The tapered 
shoulders are angled inwardly or beveled from the bottom upwardly so that 
as the cup assembly 13 is assembled to the bottom of the fork assembly 11, 
the wall 22 and the lip 40 of the cup assembly deflect inwardly as the cup 
rim or lip 40 passes over the tapered shoulders until the lip 40 snaps 
into position over the top of the shoulders which retain the cup assembly 
13 assembled against the bottom of the cap 25. In such assembled position, 
the opening 62 in the wall 22 of the cup assembly is closed by the support 
60 which engages the reinforcing vanes 64 and 66 in the side wall 22 
providing added support for the cup assembly 13. 
The lock means 16 includes a button 130 having a tapered or conical 
interior face 132. The tapered interior face 132 is in close proximity 
with an oppositely tapered face 134 forming a back portion of the support 
60 to thereby define a locking groove 136 which is adapted to receive a 
quantity of dental floss therein. The conical faces 132 and 134 intersect 
at a sharp angle forming a very thin slot into which the floss 32 may be 
forced to lock it against displacement. 
The dental floss spool 30 holds 50 yards of waxed or unwaxed nylon dental 
floss 32 and is commercially available from Belding Corticelli Thread 
Company of Charlotte, N.C. or other well known suppliers. 
In order to assemble the dental floss tool 10, the molded cup assembly 13 
receives the dental floss spool 30 over the shaft 24 in press fitted 
engagement. The fork assembly 11 is brought into proximity with the floss 
32 and a length of floss 34 is drawn through the aperture 26. The top cap 
25 is then snap fitted over the cup rim 40 for secure engagement 
therewith. Finally, the spring leg 116 of the cutter assembly 108 is slid 
through the opening 119 in the top cap 25 and into assembled engagement 
with the fork assembly 11 as shown in FIG. 3 to complete the assembly of 
the tool 10. 
In use, an 18 inch length of floss 34 is initially withdrawn from the 
aperture 26 and the portion adjacent aperture 26 is secured by wrapping it 
once around the lock means 16 in the groove 136 whereby it is securely 
entrapped. The floss is then run along the groove 72, through the slot 
100, past the ear 90, across to the arm 80, past the ear 92, through the 
slot 98, back down the groove 86 to the locking means 16 where the floss 
34 is again wrapped two times around the locking means 16 in the groove 
136. While the floss is thus being secured, the arms 70 and 80 are bent 
inwardly toward each other so as to be approximately 3/4" apart at their 
free ends. Thus, in order to make sure that the floss 34 is adequately 
tensioned for use, while the floss is being threaded along the arms 70 and 
80, the arms 70 and 80 are squeezed together slightly taking advantage of 
their flexible nature. When the floss 34 has been secured at both ends, 
the arms 70 and 80 are released, thereby drawing the length of floss 34 
taut between the arms 70 and 80. After the dental floss tool 10 has been 
used, if it is desired to reuse it, it is first necessary to unlock the 
ends of the floss 34 from the locking means 16 to permit the user to 
withdraw an additional 8" of floss from the storage housing 12 through the 
aperture 26. The floss is then locked again to the lock means 16 engaging 
first the attached end into the groove 134 and then inserting the floss 
into the grooves 72 and 86 as described above. The other end of the floss 
is then secured in the lock means 16 and the used portion of the floss, 
about 8" is cut off in the cutter assembly 108. 
Thus, it may be appreciated that an economical dental floss tool 10 is 
herein disclosed which uses very little dental floss and is very compact. 
The dental floss tool 10 also provides positive securing of both ends of a 
length of dental floss 34 to prevent it from loosening while the floss is 
in the user's mouth. The structure of the arms 70 and 80 with their 
grooves 72 and 86 provides an improved means for protecting the floss that 
is not actually engaged with the teeth and protecting the portions of 
mouth from engaging the floss. 
While there has been illustrated and described a particular embodiment of 
the present invention, it will be appreciated that numerous changes and 
modifications will occur to those skilled in the art, and it is intended 
in the appended claims to cover all those changes and modifications which 
fall within the true spirit and scope of the present invention.