Spray nozzle

BACKGROUND OF THE INVENTION

Field of the invention

This invention relates to a new and improved spray nozzle for use with oral hygiene appliances of the type which produce a stream of liquid to be directed against the teeth and gums for cleansing and massaging.

Description of the prior art

Oral lavage appliances of the type mentioned above may produce either a steady stream of liquid or a pulsating stream of liquid in which the pulsations are of variable frequency and kinetic energy to aid in cleansing the teeth and .massaging the gums. The steady of pulsating stream of liquid is directed through a spray nozzle and spray nozzle tip which must be inserted into the mouth so that all parts of the teeth and gums may be sprayed. Spray nozzles presently used with such appliances are tapered to a reduced diameter at the tip or have sharp edges which may irritate ar scratch tender gums when inserted into the mouth.

Spray nozzles presently used also produce a single concentrated high-speed jet of liquid which massages the gums and dislodges food particles, but which does not cover a sufficient area to effectively flotation cleanse the mouth of particles so dislodged.

Furthermore, the spray emerging from spray nozzle tips presently used with oral lavage appliances is subject to minor mechanical variations in the operation of the liquid pump and drive motor. In addition, with oral lavage appliances of the type which produce a pulsating stream, present spray nozzles produce air pockets between pulses resulting in erratic performance and sharp peaks.

SUMMARY OF THE INVENTION

It is an object of this invention to provide an improved spray nozzle tip which produces in addition to a concentrated high-energy jet of liquid, a broad low-energy fan stream surrounding the central jet stream to provide flotation cleansing over a broad area of the mouth to effectively remove particles dislodged by the concentrated jet stream.

A further object of the invention is to provide an improved spray nozzle with spray stability by providing a pre-loaded liquid head at the spray nozzle tip.

An additional object of the invention is to provide a spray nozzle whose tip is set at a convenient angle and formed with a rounded head so that when the nozzle is held by the hand in a relaxed position the liquid jet will be directed at the teeth and gums with no danger of scratching or irritating tender or ailing gums.

Yet another object of the invention is to provide a spray nozzle for use with oral lavage appliances in conjunction with a toothbrush.

In order to accomplish these results my invention contemplates the provision of a spray nozzle comprising an elongated annular tube having therein a liquid channel terminating in a cavity at one end of the tube and having an outlet of reduced diameter leading from the cavity of the atmosphere flared at its outer end to thereby provide in addition to a concentrated jet stream of liquid, a surrounding diffuse fan stream of liquid when liquid is pumped through the liquid channel. Another aspect of my invention contemplates the provision of a toothbrush in conjunction with the spray nozzle, secured at the spray nozzle tip.

Brief description of the drawings

In the accompanying drawings:

FIG. 1 is an environmental view of a spray nozzle embodying my invention in which the spray nozzle is shown in use with accessories of an oral hygiene appliance.

FIG. 2 is a cross-sectional side elevational view of the spray nozzle tip illustrated in FIG. 1.

FIG. 3 is a cross-sectional view of the spray nozzle tip illustrated in FIG. 2, along the line 3—3 in the direction of the arrows.

FIG. 4 is a side elevation cross-sectional view of another embodiment of my invention in which a toothbrush is provided in conjunction with a spray nozzle similar to the one illustrated in FIG. 2.

FIG. 5 is a side elevation view of the spray nozzle and toothbrush assembly illustrated in FIG. 4, looking down on the bristles.

FIG. 6 is a top elevation view of the spray nozzle and toothbrush assembly illustrated in FIG. 5.

FIG. 7 is a partially cross-sectional side elevation view of another spray nozzle and toothbrush assembly similar to the one illustrated in FIG. 4.

Description of the preferred embodiment

In the embodiment of my invention illustrated in FIG. 1, I provide an elongated tube 1 terminating at its outlet end in a rounded tip 2, and terminating at its inlet end in a coupling 3 adapted to be inserted into and held in water-tight relationship by the complementary coupling in an accessory of an oral hygiene appliance, which complementary coupling forms the liquid discharge outlet 30 of the oral hygiene appliance. I also provide a hand grip 4 to facilitate handling the nozzle during use.

The oral hygiene appliance to which the spray nozzle is coupled may produce a steady stream of liquid or it may produce a pulsating stream of liquid in which the pulsations are of a variable frequency and kinetic energy. The spray nozzle of the present invention has been successfully used with the oral hygiene appliance produced by Troy Industries, Tuckahoe, N.Y., under the trademark Dent-O-Pick. The liquid discharge accessories of an oral hygiene appliance 11 of this type are drawn in phantom in the environmental illustration of FIG. 1.

Referring more particularly to the spray nozzle tip as illustrated in FIG. 2, the liquid channel 5 of the spray nozzle tube 1 terminates in a cavity 6 at the spray nozzle tip 2. The cavity 6 is formed by a bend 12 in the spray nozzle tube 1 near the end of the spray nozzle tube. The angle of the bend should be such that when the spray nozzle is held in the hand at a comfortable position the stream of liquid from the tip of the nozzle will be directed towards the gums and teeth. An angle of approximately 90° to 130° has been found satisfactory, and approximately 115° to 120° preferable.

The dimension of the inner diameter of the liquid

3,487,828 channel 5 in the spray nozzle tube is preferably reduced at the bend as illustrated in FIG. 3, thereby producing the reservior 6. If the spray nozzle were constructed without such a bend, the desired reservoir might be produced by a restriction in the liquid channel at a point near the tip. As an example, if the outer diameter of the annular tube of the spray nozzle is of the order of .187 inch, and the inner diameter of the liquid channel in the annular tube is of the order of .070 inch, then the inner diameter may be as small as .050 inch or .060 inch at the bend or restriction.

When the spray nozzle is used in conjunction with an oral lavage appliance which produces a pulsating stream of liquid, the reservoir or cavity 6 prevents run back of the liquid between pulses. Run back of the liquid may create undersirable air pockets in the liquid so that the pulsating stream is erratic, with sharp peaks. On the other hand the reservoir of liquid in the present invention produces a uniformly pulsating stream. To this end, the reservoir should have a volume at least equal to the volume of water displaced during one cycle or pulsation by an oral lavage appliance pump. That is, the reservoir should have a volume at least equal to the volume of water discharged through the tip during each pulsation.

Furthermore, the pre-loaded liquid head in the reservoir dampens the effect of minor variations in the operation of the pump and driving motor of the oral lavage appliance on the stream of liquid sprayed from the nozzle tip.

Leading from the cavity 6 is the spray nozzle tip outlet 7 of reduced diameter. The outlet 7 is flared at the outer surface of the spray nozzle tip to form a diverging mouth 8. The relative dimensions of the spray nozzle tip are illustrated in FIG. 3 which is a cross-sectional view of the spray nozzle tip through the cavity 6. Thus, the outlet 7 of reduced diameter from reservoir or cavity 6 and the flared mouth 8 of the outlet are shown. As an example, if the inner diameter of the outlet of reduced diameter is of the order of .025 inch and the inner diameter of the reservoir or cavity is of the order of .070 inch, then the diameter of the flared portion of the outlet at the surface of the nozzle tip may be as wide as .065 or .070 inch.

When using the spray nozzle in conjunction with an oral hygiene appliance, liquid at least equal in volume to or in excess of what may be displaced from the spray nozzle outlet during one pulsation, is pumped into the cavity 6 to provide a reservoir of liquid under pressure which acts as a stabilizer when producing a pulsating stream of liquid or in the event of minor variations in the operation of the pump and its driving motor when producing either a pulsating or steady stream thereby providing stability in the steady or pulsating liquid jet propelled from the spray nozzle outlet.

Liquid under pressure escaping through the outlet 7 of reduced diameter produces a central high-energy liquid stream 9. When the liquid reaches the flared portion 8 of the outlet 7, however, the sudden drop in pressure encountered by the outer annular layers of liquid causes the outer annular layers to flare outward to form a diffuse fan stream of liquid surrounding the concentrated central liquid jet.

While the central concentrated liquid jet dislodges food particles and massages the gums, the broader fan stream surrounding the central jet stream effectively irrigates wide areas of the mouth and removes dislodged particles by flotation cleansing. Turbulent movement of the volume of water moved through the spray nozzle tip outlet further effectively cleanses the mouth and stimulates the gums.

In another form of my invention a toothbrush is provided in conjunction with the spray nozzle as illustrated in FIGS. 4-6. Within a toothbrush base 13, tufts 14 of bristles are permanently held. The base 13 is secured to (he elongated {ul?e 15 of the spray nozzle ju§t below the spray nozzle tip 16. The spray nozzle is similar to the one illustrated in FIG. 2 and includes a liquid channel 17, bend 18, reservoir 19, outlet 20, and flared mouth 21 at the discharge end of the outlet.

The base of the toothbrush and the annular tube of the spray nozzle may be formed as a unitary piece from material such as plastic, or as separate pieces secured together.

In the form of the invention illustrated in FIGS. 4-6 the spray nozzle tip projects in a direction parallel to the tufts of bristles, and perpendicular to the liquid channel in the elongated tube. In the form of the invention illustrated in FIG. 7, the spray nozzle and toothbrush are similar to that illustrated in FIGS. 4-6 except that the spray nozzle tip forms an angle of approximately 115° with the liquid channel or approximately 25° with the tufts of bristles. The elongated tube 22, liquid channel 23, reservoir 24, spray nozzle tip 25, outlet 26, flared mouth 27, toothbrush base 28, and tufts 29 of bristles are formed in the manners described above.

Alternatively the elongated tube may be formed without a bend near the tip and the toothbrush secured adjacent the outlet. In such a case the liquid channel may terminate in an outlet along the side of the tube near the tip rather than at the tip itself.

In each case in which the spray nozzle is provided with a toothbrush the bristles may be formed of a material having antifrictional “nonstick” releasing properties such as polytetrafluoroethylene or other fluorinated organic polymers so that they may be readily cleaned in water.

In using the spray nozzle and toothbrush assembly, the spray and brush may be used simultaneously or the teeth may be first brushed and subsequently the teeth and gums subjected to the spray.