TOOTHBRUSH WITH ADJUSTABLE HAND GRIP Background of the Invention It has been found that there is a preference by users of toothbrushes to have a number of different gripping styles which could be used by the consumers when brushing their teeth. Given these different styles it is difficult to design one handle shape which will accommodate this mul- titude of gripping styles. It would be desirable if it were possible to provide a toothbrush handle having the capabil- ity of being adjustable in its diameter and to a lesser ex- tent in its overall length. Such a handle with an adjust- able grip would lend itself to help people with different types of disabilities, such as arthritis, to properly brush their teeth.

Summary of the Invention An object of this invention is to provide a toothbrush with an adjustable handle grip.

A further object of this invention is to provide such a toothbrush wherein the diameter of the grip could be easily adjusted by a consumer.

In accordance with this invention the toothbrush includes a handle having a head attached at one end of the handle. The head carries cleaning elements, such as bris- tles. The handle is hollow and includes an outer sleeve made of an elastomeric material. The sleeve includes a first end disposed toward the head and a second end located remote from the head with a central portion between the

ends. The central portion is expandable so as to increase its diameter in accordance with the desires of a consumer.

In one practice of the invention, the expansion results from the application of force within the hollow han- dle outwardly against the central portion so that the cen- tral portion expands from a first diameter to a larger sec- ond diameter. During the expansion the first end of the sleeve remains anchored at a constant distance from the head in both the first diameter and second diameter conditions of the central portion. In one embodiment of this invention the sleeve is made from a soft thick compressible material which expands when the longitudinal force is applied against the second or outer end of the sleeve to cause the length of the handle to contract while the sleeve bulges outwardly.

In a further embodiment of this invention the sleeve is in the form of a thin elastic skin which is ex- panded when a knob at the second end of the sleeve is ro- tated to cause force applicating members which are part of an expansion wheel to move outwardly and press against the inner surface of the sleeve. The force applicating members may be curved spokes which are pivoted to the shaft and piv- oted against the sleeve. The spokes are in a generally tight circle before the sleeve is expanded. The spokes are then rotated into a radial direction on their shaft to cause the sleeve to expand.

In a still further embodiment of this invention the sleeve is in the form of a thin elastic skin over the expansion chamber. The skin is stretched outwardly under

the pressure of air within the chamber in the central por- tion of a handle. The air is forced into the chamber by a squeeze pump on the handle.

The Drawings: Figure 1 is a top plan view partially broken away and in section of a toothbrush, in accordance with one em- bodiment of this invention; Figure 2 is a view similar to Figure 1 showing the toothbrush in an expanded condition; Figure 3 is a cross-sectional view taken through Figure 1 along the line 3-3; Figure 4 is a top plan view partially broken away and in section of a further toothbrush in accordance with a second embodiment of this invention; Figure 5 is a cross-sectional view taken through Figure 4 along the line 5-5; Figure 6 is a view similar to Figure 5 showing the toothbrush handle in its expanded condition; Figure 7 is a side elevational view of a modified form of the toothbrush that is shown in Figures 4-6 wherein the expansion is in response to a motor drive; Figure 8 is a fragmental side elevational view of yet another toothbrush handle in accordance with a further embodiment of this invention; and Figure 9 is a fragmental side elevational view of a portion of the toothbrush shown in Figure 8.

Detailed Description

The present invention is directed to providing a single toothbrush handle structure which is capable of being adjusted in its diameter. In one practice of the invention the adjustment results from the application of a force in the longitudinal direction to cause the handle to bulge out- wardly. In a second practice of the invention the adjust- ment results from a rotational movement applied to a portion of the handle. In a third embodiment of this invention the expansion or adjustability results from the application of pressure namely from the pumping of air into the hollow han- dle to cause the handle to bulge outwardly without requiring any longitudinal or rotational movements by the consumer.

Figures 1-3 illustrate a toothbrush 10 in accor- dance with one embodiment of this invention. As shown therein toothbrush 10 includes a handle 12 and a head 14.

Head 14 would carry any suitable number of cleaning elements such as tufts of bristles as is known in the art. Any suit- able number, type, orientation, etc. of cleaning elements may be used in the various practices of this invention. The invention is particularly directed to providing structure which causes a portion of the handle to bulge outwardly so as to increase its diameter.

As shown in Figures 1-2 the handle 12 includes an outer hollow sleeve 16 made of an elastomeric material which is generally soft and thick as well as being compressible.

A first end 18 of the sleeve 16 is anchored at a location in the general area of the head 14. The second or remote end 20 of sleeve 16 is located at the opposite end of handle 12.

As illustrated a hollow tubular member 22 is mounted within the hollow sleeve 16. Member 22 includes a passageway 24 which is provided with locking structure 26 at spaced loca- tions along its length. An elongated shaft 28 is located axially within the passageway 24 of tubular structure 22.

Shaft 28 may terminate in a knob 30 which abuts against the outer surface of second or remote end 20 of sleeve 16. A portion of sleeve 16 between ends 18 and 20 is the central portion which is capable of being expanded from a first minimum diameter illustrated in Figure 1 to an enlarged sec- ond diameter the size of which would vary in accordance with the intent of the consumer. Figure 2, for example, shows one enlarged diameter illustrated in solid lines and a sec- ond larger diameter illustrated in phantom lines.

In order to expand the size or diameter of the central portion of sleeve 16 force is applied in the longi- tudinal direction as shown by the arrow 32 in Figure 2. Be- cause end 18 is anchored, the application of the longitudi- nal force causes the sleeve 16 to bulge outwardly thereby increasing its diameter. As the diameter is increased the overall length of the handle and particularly the sleeve 16 is decreased. This is also shown in Figure 2.

Any suitable structure may be used for creating the inward movement of remote end 20 of sleeve 16 and then locking the remote end in position to prevent a return move- ment when the desired diameter has been reached. Figures 1- 3 illustrate one form of force applicating structure which includes the shaft 28 to have a retaining pin 34. Such a

pin 34 could extend on each side of shaft 28 as shown in Figure 3. In practice shaft 28 would be moved inwardly by pressing against knob 30. Retaining pins 34 are located for movement through passageway 24 by either pressing against the locking structure 26 as the pins are forced past the locking structure. When the desired diameter has been reached the force 32 is no longer applied. Pins 34 are then permitted to enter the locking structure 26 to prevent a rearward or return movement of shaft 28 which would other- wise result in the sleeve 16 returning to its original posi- tion.

The locking structure may be of any suitable form.

Figures 1-2 illustrate the locking structure 26 to be of the bayonet type. If desired the locking structure could be similar to a rack with the teeth inclined in a direction op- posite that of structure 26. The pins 34 would act as pin- ions which would travel over the teeth of the rack and then be held in position when the desired diameter is reached.

Other mechanisms could include some slight rotational move- ment in addition to the longitudinal movement so that the shaft 28 could be rotated sufficiently to engage the pins 34 with the locking structure 26 of tubular member 22 when the desired diameter has been reached. Still other mechanisms such as screw threads could also be used.

If desired the expansion of the soft outer sleeve 16 could be assisted by a set of longitudinal plastic slats or wires which would also provide for a more uniform expan- sion. Such slats or wires would be mounted at one end to

shaft 28 near its knob 30 and mounted at the opposite end near anchor end 18 of sleeve 16. When force 32 is applied to move shaft 28 inwardly the slats or wires would bulge outwardly. Since the slats or wires would be disposed against the inner surface of sleeve 16 the outward bulging of the slats or wires would cause the sleeve 16 to similarly bulge outwardly. The provision of such slats or wires could be in addition to or could be instead of having the tubular member 24 and its locking structure 26.

Figures 4-6 illustrate a further embodiment of this invention wherein the toothbrush 10A has its sleeve in the form of a thin expandable skin 40. The skin 40 of hol- low handle 14A would have an anchor end 18A and a remote end 20A. Sleeve 40 would be expanded as a result of a rotational movement applied to the handle rather than the longitudinal movement of the handle in Figures 1-3.

As shown in Figures 4-6 a shaft 28A is provided within the hollow handle 14A. Shaft 28A terminates in an exposed knob 30A which abuts against remote end 20A of skin 40. An expansion wheel 42 is mounted on shaft 28A. Expan- sion wheel 42 is in the form of a plurality of force trans- mitting members. As best shown in Figures 5-6 these force transmitting members are spokes 44 which are preferably curved. One end 46 of each spoke 44 is pivotally mounted to shaft 28A. The opposite end 48 of each spoke 44 is pivo- tally mounted to skin 40 such as by being mounted to rein- forcing shoe 50 with each shoe 50 being permanently secured to the inner surface of skin 40. In the initial condition

shown in solid lines in Figure 4 and also shown in Figure 5 the spokes 44 are disposed in a very tight circle in this collapsed condition. Thus, skin 40 is at its minimum diame- ter. As knob 30A is rotated shaft 28A is also rotated caus- ing the spokes 44 to move toward a radial condition pointing outwards from the longitudinal axis of the handle as shown in Figure 6. By moving the spokes 44 in a radial direction the skin 40 is caused to expand outwardly to the position shown in Figure 6 and also shown in phantom in Figure 4.

Where skin 40 is made of a stretchable material, the length of the handle remains the same when the skin has been ex- panded. Where skin 40 is less stretchable, the handle length decreases as skin 40 expands.

If desired, the inner surface of skin or sleeve 40 may include an inwardly extending partition 52 having de- tents 54. Wheel 42 may likewise include one or more pins 56 such as located on the spokes 44 so that as the spokes ex- tend in a more radial direction causing the skin 40 to ex- pand the pins 54, which could also function as the pivot pins for the ends 48 of spokes 44, would remain generally in line with the detents 52. The knob 30A could be moved in- wardly to cause the pins 56 to be locked into detents 54 thereby preventing any reverse rotation of shaft 28A. Al- ternatively, such added anti-rotational structure could be omitted and the length of handle and its sleeve 40. could re- main constant even while the skin or sleeve 40 expands since the skin 40 is made of a stretchable or expandable material

which need not be reduced in length in order to permit the expansion as was the case for sleeve 16 of Figures 1-3.

Figure 7 shows a variation of the embodiment of Figures 4-6 where the rotation of the shaft is electrically controlled. Thus, as shown in Figure 7 the shaft 28A is the shaft of a motor 58 powered by batteries 60 under the con- trol of switch 62 so that the actuation of switch 62 turns on the motor 58 to rotate shaft 28A and expansion wheel 42.

The handle may be closed by threaded cap 64 which would per- mit selective access into the interior of the handle for the installation and replacement of batteries 60.

Figures 8-9 illustrate yet another embodiment of this invention wherein the toothbrush 70 has a sleeve in the form of an elastic outer skin 40 anchored at one end near the head and anchored at the other end 72 to a pump struc- ture 74. Pump structure 74 includes a squeeze pump 76. At- mospheric air enters the pump 76 through an air intake pas- sage 78 having a one way valve 80. When pump 76 is squeezed the air within the pump 76 flows through passage 82 past one way valve 84 into the hollow interior which is covered by skin 40. The pump also includes a bleed valve 86. As air is pumped into the hollow interior the chamber of the hollow interior must expand to accommodate the incoming air. This expansion results in providing an air pressure against the inner surface of skin 40 to cause the skin 40 to bulge out- wardly. In this embodiment of the invention the length of the handle remains the same as its diameter is increased or inflated. Alternatively where skin 40 is less stretchable,

the expansion of skin 40 pulls the pump end of the handle inwardly to decrease the length of the handle.

A variation of the toothbrush 70 shown in Figures 8-9 would be to provide a bellows formation within the cham- ber closed by the elastomeric sleeve or skin 40. Air could be pumped into the bellows formation to cause the bellows to expand and thereby expand the skin. The invention could also be practiced where instead of air a liquid or other fluid or gas could be provided in a sac and forced into the bellows formation where the fluid could pressurize and cause the bellows to expand.

In each of the embodiments described herein it is possible to reduce the diameter of the handle after a pre- selected expansion has been achieved if it is desired to use a smaller diameter handle. With the embodiment of Figures 1-3 there would be a disengagement of the locking structure between shaft 28 and inner tubular member 24 to permit the shaft 28 to be moved toward its original position in a di- rection away from the head 14. In the embodiment of Figures 4-6 the diameter of the expanded handle could be reduced by reversing the direction of rotation of shaft 28A so that the spokes 44 again begin to approach a tighter condition which is less radial. In the embodiment of Figures 8-9 air could be expelled through the bleed valve 86 to reduce the amount of air within the hollow handle thereby permitting skin 40 to contract until the desired reduced diameter is reached.

While the various figures illustrate the toothbrushes to be of the manual type the invention could

also be practiced with an electrical toothbrush having at least one movable section in the head. The motor and bat- teries for powering the section could be mounted in a cen- tral portion of the handle. The motor shaft for moving the one or more sections of the head would extend through the remainder of the handle and into the head. Such electric toothbrush could include one or more sections which are power driven in one or more different types of manners such as by rotational oscillation, continuous rotation in the same direction, linear oscillation in a longitudinal direc- tion and/or linear oscillation in a transverse direction, as well as a rocking back and forth.

Where a power operated toothbrush is used the bat- teries for powering the motor could be arranged in longitu- dinal series instead of being side by side to minimize space requirements. Additionally, small disc type batteries such as used in watches, cameras, etc. could be used for powering the motor.

As should be apparent the invention thus provides a toothbrush having a handle of an initial reduced diameter size. The consumer may then increase the diameter of the handle to achieve the. desired diameter for that consumer by simple manipulations of the handle. The invention also pro- vides for the possibility of having different size handle adjustment selectability including reducing the handle di- ameter from an expanded to a less expanded condition.