Background of the Invention
As evidenced by representative U.S. Pat. No. 4,048,690 (Wolfson--9/20/1977), the prior art recognizes that previously unattainable dental cleaning benefits are attainable with "twinbrushes rotary toothbrushes" wherein the twin-brushes angular reciprocate in unison. During each co-angular reciprocation of the twinbrushes, the following gingival area cleaning simultaneosuly occurs at the bucal and lingual teeth sides: at the first angular movement, inimical plaque is abradably removed; and at the second angular movement, said removed plague particles are swept directionally away from the sensitive gingival sulcus. Moreover, another heretofore unattainable cleansing simultaneously occurs to the bucal and lingual sides during each co-angular reciprocation of the twin-brushes, namely the vertically extending inter-proxial juncture areas of adjacent teeth are cleansed directionally away from the sensitive gingival sulcus.
Although U.S. Pat. No. 4,048,690 describes "twin-brushes rotary toothbrushes" that have theoretically solved the aforementioned dental cleaning problems, it teaches a bulky and structural mounting and actuation for the twin-brushes and to the extent that a so constructed twin-brushes rotary toothbrush is too large to fit and operationally function within the mouth of persons anatomically endowed with average or small size mandible.
And although U.S. Pat. No. 4,048,690 does teach usage of auxilary bristles (and located between the twin-brushes) for simultaneously cleaning teeth occlusial surfaces, it is difficult for the operator to simultaneously reciprocate the auxiliary occlusial brushes and the bucal/lingual twin-brushes.
General Objective of the Invention
It is accordingly the general objective of the present invention to provide a twin-brushes rotary toothbrush concept that represents marked improvement over those of the prior art. It is an ancillary general objective to provide a twin-brushes rotary toothbrush that is unusually compact and to such extent that it will readily fit and operationally function within the mandible anatomy of most male and female persons, that reliably performs substantially all required dental cleansing tasks, and that is easy for the operator to simultaneously perform required occlusial, bucal, and lingual cleansing tasks.
General Statement of the Invention
With the above general objectives in view, and together with other related and specific objectives which will become more apparent as this description proceeds, the twin-brushes rotary toothbrush concept of the present invention generally comprises: a directionally longitudinally extending hollow barrel having a fore-end and a rear-end; longitudinally extending and longitudinally reciprocatable strokearm means located predominately within and connected to the barrel, the strokearm means having a forward-portion that is always located forwardly of the barrel; and a pair of transversely separated upright rotary brushes located forwardly of the barrel and flanking the strokearm means forward-portion, the strokearm means forward-portion carrying transversely extending crankshafts bearing against slotted portions of the brushes whereby, as the strokearm means longitudinally reciprocates, the twin-brushes are caused to move together and in alternating angular directions.
Brief Description of the Drawing
In the drawing, wherein like characters refer to like parts in the several views, and in which:
FIG. 1 is a top plan view of a representative embodiment "T" of the twin-brushes rotary toothbrush concept of the present invention;
FIG. 2 is a longitudinally extending sectional elevational view of embodiment "T" and taken along line 2--2 of FIG. 1;
FIG. 2A is a sectional elevational view related to FIG. 2 and showing that a powering means has caused a strokearm means to longitudinally reciprocate;
FIG. 3 is a sectional elevational view taken along line 3--3 of FIG. 1;
FIG. 4 is a sectional view taken along line 4--4 of FIG. 3;
FIG. 5 is a longitudinally extending sectional elevational view similar to FIG. 2 but of an alternate toothbrush embodiment "TA"; and
FIG. 6 is a sectional view related to that of FIG. 4.
Detailed Description of the Drawing
Turning initially to drawing FIGS. 1-4 which depict a representative embodiment "T" of the twin-brushes rotary toothbrush concept of the present invention. Embodiment "T" generally comprises: a horizontally and directionally longitudinally extending barrel 10 having an upright fore-end 12, an upright rear-end 19, and horizontally longitudinally extending topside 10A and bottomside 10B; as an angularly reciprocatable coordinator, a pinion 20 co-revolvably surrounding a barrel-pivot (e.g. pin 15) that directionally transversely intersects barrel 10; as a reciprocatable strokearm means, a pair of substantially parallel, longitudinally extending, and vertically offset strokearms 30 and 40, the strokearms forward-portions (32, 42) always being located forwardly beyond barrel fore-end 12 and the strokearms rack-teeth rearward-portions (37, 47) being within the barrel and there engaged with vertically opposite sides of pinion 20 whereby the strokearms might longitudinally reciprocate and respectively in opposite longitudinal directions; a pair of transversely separated upright rotary brushes 60(M) and 60(N) positioned wholly forwardly of barrel fore-end 12 and being respectively actuatably associated with strokearm crankshafts (31, 41) whereby the brushes move together in angular reciprocation as the strokearms longitudinally reciprocate; and together with ancillary features such as powering means (e.g. 50), a manually graspable handle (e.g. 70), etc.
Barrel 10 at its fore-end 12 is centrally open (13) to permit passage therethrough of the strokearm means (e.g. 35, 45) and which means is predominately located within the barrel hollow interior (14). Between barrel ends 12 and 19, there is a horizontal and directionally transversely extending barrel-pivot such as a barrel-pin 15 and is rotatably secured to the barrel longitudinally extending upright sides.
A contra-directional coordinator (e.g. 20, 25) is locatable within barrel 10. For example, as seen in FIGS. 2 and 2A, a said coordinator ensures that two strokearms (35, 45) simultaneously longitudinally reciprocate, and respectively in opposite longitudinal directions. In embodiment "T", the contra-directional coordinator comprises a pinion 20 that co-revolvably surrounds barrel-pin 15.
Upper strokearm 35 has a medial-portion 33 that is longitudinally slidably disposed along the medial-portion 43 of the lower-strokearm 45. Upper-strokearm 35 has a longitudinally extending rack-teeth rearward-portion 37 overlying and enmeshed with pinion 20. Similarly, lower-strokearm 45 has a longitudinally extending rack-teeth rearward-portion 47 underlying and enmeshed with pinion 20. Forwardly beyond barrel fore-end 12, the upper strokearm forward-portion carries a pair of transversely extending and transversely aligned crankshafts 31. Similarly, the lower-strokearm forward-portion carries a pair of transversely extending and transversely aligned crankshafts 41. Inasmuch as the strokearms 30 and 40 are longitudinally slidably engaged (e.g. at 33, 43): crankshafts 31 remain at constant elevation as upper-strokearm 35 longitudinally reciprocates; and crankshafts 41 remain at a constant elevation (though below crankshafts 31) as lower-strokearm 45 longitudinally reciprocates. The upper-strokearm forward-portion can be provided with an upwardly extending bristles array 30U; and similarly, the lower-strokearm forward-portion can be provided with a downwardly extending bristles array 40L.
Transversely separated and upright brushes 60(M) and 60(N), which circularly surround a common transverse-axis 59, respectively include an array of bristles 62 extending transversely toward the strokearm means to terminate at bristles upright-planes 62G. Radially above transverse-axis 59, the leadward-side upright 61 of each brush is provided with an elliptically upper slotted portion 63 for journalling crankshafts 31. Analagously, but radially below transverse-axis 59, the leadward-side 61 of each brush is provided with an elliptically lower slotted portion 64 for journalling crankshafts 41. Accordingly, as stroke-arms 30 and 40 reciprocate in opposite longitudinal directions, the crankshafts 31 and 41 bear longitudinally against the brushes whereby the brushes move together and in synchronization with the angular reciprocation of the contra-directional coordinator (20, 25).
There are means for maintaining a fixed transverse spacing between brushes 60(M) and 60(N). For example, as alluded to in FIG. 6, one such means might take the form of an axle member 58 extending along transverse-axis 59 and affirmatively connecting the two brushes with an axle. And as suggested by FIG. 4, an alternate such means entails affirmatively attaching the crankshafts 31 and 41 to the brushes, such as with fastener grommets (31K, 41K). In the latter regard, the trailward-side of each brush is recessed (65) to communicate with the leadward-side slots (63, 64) to accommodate the grommet fasteners (31K, 41K) for crankshafts 31 and 41, respectively. The brush trailward-side is then provided with a smoothly contoured removable cap 66 that is frictionally engaged within said recess 65. However, both such means (i.e. axle 58 and fasteners 31K, 41K) might be simultaneously employed for enhancing the toothbrush durability.
The aforementioned elements (10, 20, 35, 45, 60(M), 60(N)) represent a self-sustaining structure that might be removably attached to an upright and manually graspable handle member (e.g. 70). For example, horizontal screws 79 extending through handle apertures 79 might threadedly engage barrel rear-wall 19. Herein, and immediately above its lower-end 71, handle member 70 is optionally provided with a handle-grip frontal contour 72.
Apt powering means might be employed for longitudinally reciprocating the strokearm means so that the two brushes are caused to co-movably angularly reciprocate about common transverse-axis 59. In the case of dual-strokearms (e.g. 35, 45), such powering means might be directly connected to one or both strokearms, or alternatively, to the contra-directional coordinator. For embodiments "T" and "TA", the powering means 50 comprises a finger actuatable trigger 51 flanking barrel 10 and affirmatively attached to barrel-pin 15. The trigger 51 extends below barrel bottomside 10B, and hence, locatable forwardly of handle member 70. A helical spring 56, herein surrounding a rod extension 73 of handle 70, is interposed between trigger 51 and handle 70 whereby spring 56 tends to maintain the strokearms positions of FIG. 2. However, whenever trigger 51 is resiliently depressed toward handle 70, the strokearms assume the positions depicted in FIG. 2A. Thus, for each depression and release of trigger 51, the reciprocating strokearm bristles 30U and 40L brush the dental occlusial surfaces while the brush bristles 62 simultaneously efficaceously sweep the dental bucal and lingual surfaces.
As previously mentioned, powering means for the strokearm means might be other than the trigger style and other than power directly applied to a dual-directional coordinator (e.g. 20, 25). For example, hydraulic, pneumatic, and cordless-rechargeable electric cable type powering means might be made to act directly upon the strokearm means.
In drawing FIG. 3, solid lines for crankshafts 31 and 41 and for the brush slotted portions indicate the FIG. 2 strokearm positions, while phantom lines for elements 31, 41, 63, and 64, indicate the FIG. 2A strokearm positions. Also in FIG. 3, the two double-headed curved arrows indicate that the two brushes 60(M) and 60(N) move together between FIGS. 2 and 2A conditions at angular reciprocations of substantially 75.degree. to 105.degree., and preferably of about 90.degree..
A comparison of analagous drawing FIGS. 2 and 5 reveals that the FIG. 5 alternate embodiment "TA" differs from embodiment "T" in the following respects:
(i) the embodiment "TA" strokearms 30A and 40A have shapes differing slightly from those of embodiment "T". Moreover, forwardly adjacent their rearward ends (39A, 49A), the respective strokearms 30A and 40A are provided with openings 36 and 46, respectively; racks 37 and 47 of strokearms 30 and 40 are eliminated; and
(ii) the embodiment "TA" contra-directional coordinator comprises a dual-fingers rocker member 25 having respective fingers extending through openings 36 and 46; rocker member 25 corevolvably surrounds barrel-pin 15.
Accordingly, as a powering means (e.g. 50) causes barrel-pin 15 and rocker member 25 to angularly reciprocate, strokearms 30A and 40A longitudinally reciprocate and cause brushes 60(M) and 60(N) to angularly reciprocate in synchronization with rocker member 25. By virtue of threaded apertures 18, which are engageable with said screws 79, embodiments "T" or "TA" can be readily replaced with another such unit.
From the foregoing, the construction and operation of the twin-brushes rotary toothbrush concept will be readily understood and further explanation is believed to be unnecessary. However, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact constructions shown and described, and accordingly, all suitable modifications and changes be resorted to, falling within the scope of the appended claims.