Drive mechanism for interproximal flossing device
An interproximal flossing device including a link member that isolates lateral from vertical rotational movement to transfer only translatory arcuate movement. This is done by the combination of a hinge and pivot structure. A tip attachment structure is also included for secure placement of the tip on the link member, and allows easy removal and replacement. A tip member removal structure is also included to allow for easy removal of the tip member from the link member.
The present application is a divisional patent application of U.S. patent application Ser. No. 10/238,666, filed Sep. 9, 2002 and entitled “Drive Mechanism for Interproximal Flossing Device”; which is a divisional patent application of U.S. patent application Ser. No. 09/636,488, filed Aug. 10, 2000 and entitled “Drive Mechanism for Interproximal Flossing Device”, now U.S. Pat. No. 6,447,293; which claims the benefit under 35 U.S.C. § 119(e) to provisional patent application No. 60/148,915, filed Aug. 13, 1999 and entitled “Interproximal Flossing Device”; the disclosures of which are hereby incorporated herein in their entireties.
FIELD OF THE INVENTIONThis invention relates to interproximal flossing devices, and more particularly to the drive mechanisms for interproximal flossing devices and the tip attachment structure associated therewith.
BACKGROUND OF THE INVENTIONAvailable interproximal flossers employ a variety of tip movements to effect cleaning interproximal spaces formed between teeth. The tip movements typically include orbital, rotational, or linear movement. Rotational movement is typically created by a direct linkage between the tip and the drive shaft of a motor mounted in the handle. As the drive shaft rotates, the linkage and tip also rotate accordingly. Typically the rotation occurs in one direction, but can also be rotary oscillation. Rotation also occurs where the tip does not rotate about its longitudinal axis, but instead rotates about an axis offset from but generally parallel to the longitudinal axis of the tip. This Orbital tip movement is often created by using an off-center weight attached to the drive shaft of an electric motor mounted in the handle, which causes the entire device to move in an orbital manner in response to the off-center rotation of the weight. Orbital movement can be considered a subset of rotational movement because the tip rotates by moving along the orbital path.
Linear movement typically requires a linkage that converts the rotational movement of the motor drive shaft into linear oscillating movement at the tip. Oftentimes this structure for converting rotational to linear movement requires an offset cam surface mounted on the shaft of the motor with an end of the linkage attached thereto to follow the eccentric as it rotates. The end of the shaft is generally loosely engaged with the offset cam surface so that the shaft only moves in a direction to create linear motion at the tip end. In the linkage used to convert rotational movement to linear movement, there can be inefficiencies due to linkage connections (such as being loosely engaged), and difficulty in quietly connecting the linkage to the motor to avoid the creation of annoying sounds, due to loose connections, when the motor operates.
In addition, the tip connection structure typically used in interproximal flossing devices utilizes simple friction to attach the tip to the active end of the drive train. This type of connection is not secure, and can wear out and be less effective as the device is used.
It is with the above limitations of the presently available interproximal flossers that the invention described and claimed herein was developed.
SUMMARY OF THE INVENTIONThe instant invention relates to a interproximal flossing device, and more particularly to the drive mechanism used in the device to create linear movement of the flossing tip. The interproximal flossing device of the present invention includes a link member that isolates lateral from vertical rotational movement to transfer only translatory arcuate movement. This is done by the combination of a hinge and pivot structure. A tip attachment structure is also included for secure placement of the tip on the link member, and allows easy removal and replacement. A tip member removal structure is also included to allow for easy removal of the tip member from the link member.
In one aspect of the invention, it includes a drive mechanism for an interproximal flosser having an electric motor with a rotating drive shaft, the drive mechanism comprising a link member having a first portion and a second portion, the first portion having a first end for attachment to the drive shaft in an off-center manner, and a second portion having a second end for receiving a tip member; a laterally-extending pivot axis formed on the link member; and a resiliently flexible hinge portion having a vertical bending axis formed on the link member. When the drive shaft rotates, the first end of the link member is rotated off-center from the drive shaft, creating vertical, lateral, and a combination of vertical and lateral movement, and the hinge isolating the non-vertical movement from the tip member while transmitting to the tip member vertical movement through the pivot, so that the tip member moves through a vertical arc.
In further detail, the hinge resiliently bends about a vertical axis to isolate the lateral movement from the tip member.
In additional detail, the hinge resiliently twists about its axial axis to isolate the non-vertical movement from the tip member motion.
In additional detail, the hinge resiliently bends about a vertical axis to isolate the lateral movement from the tip member, and the hinge resiliently axially twists about its axial axis to isolate the non-vertical movement from the tip member motion.
In further detail, the drive mechanism defined above further includes a drive member for attachment to the drive shaft, the drive member defining a recess positioned offset to the drive shaft; the first end of the link member is a ball; and the recess forms a socket for snugly rotatingly and pivotingly receiving the ball.
In another aspect of the invention, the drive mechanism includes a link member having a first portion and a second portion, the first portion having a first end, and a second portion having a second end for receiving a tip member; a means for attaching the first end of the link member to the drive shaft in an off-center manner; a laterally-extending pivot axis formed between the first and second portions; and a resiliently flexible hinge portion having a vertical bending axis formed on the link member. When the drive shaft rotates, the first end of the link member is rotated off-center from the drive shaft, creating vertical, lateral, and a combination of vertical and lateral movement, and the hinge isolating the non-vertical movement from the tip member while transmitting to the tip member vertical movement through the pivot, so that the tip member moves through a vertical arc.
There are several different means for attaching, including a cam and cam-follower structure, a ball and socket structure, a pair of gears, a pair of opposing flexible hinges, each having a laterally extending flexing axis formed on a sub-frame, a slider and slide channel having a substantially vertical motion, and a track cam surface for engagement with the first end of the link member.
In another aspect of the invention, an attachment structure for attaching a tip member to a link member of an automatic flosser includes a latch tab formed on the link member; and a latch recess formed on the tip member. When the tip member is positioned on the link member, the latch tab engages the latch recess.
In further detail, the tip member has a cup-shaped portion with an open end and an interior wall; the latch recess includes a pair of recesses positioned on the inner wall; and the latch tabs includes a pair of tabs formed on the link member to engage the corresponding latch recesses when the tip member is positioned on the link member.
In further detail, a space is formed between the link member and the inner wall of the cup-shaped portion to allow the cup shaped portion to be resiliently converted from a substantially circular form to a substantially oval shape to disengage the latch tabs from the latch recesses and remove the tip member from the link member.
In additional detail to the attachment structure as described above, the attachment structure includes a primary and secondary keying structure. The primary keying structure requires the tip member to attach to the link member in any of two orientations, with the two orientations including the width of the blade extending vertically. The secondary keying structure requires the tip member to attach to the link member in one orientation, the one orientation including the blade if curving upwardly or downwardly.
In another aspect of the invention, a structure for removing a tip member from a link member of an interproximal flosser includes a slot for receiving the tip member, the slot having side walls that converge along the length of the slot to engage and deform the tip member as the tip member is moved along the slot.
The foregoing and other features, utilities and advantages of the invention will be apparent from the following more particular description of a preferred embodiment of the invention as illustrated in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 17A-D show the tip member without the secondary key structure, and the connection structure for attachment to the link member.
FIGS. 17E-H show another embodiment of the tip member and the connection structure for attachment to the link member.
FIGS. 18A-E show the link member, including the latch tabs.
Referring first to
The linear drive linkage 32 converts orbital or rotational movement of the motor drive shaft 40 to linear movement at the flossing member 48. This is done by combining a horizontally-oriented pivot axis 52 with a vertically-oriented hinge (axis of bending is vertical), on the drive linkage 32, to effectively convert an orbital or rotational movement of the first end of the linkage into a linear movement at the second end 58 of the linkage. This linear movement is believed to be a more desirable flossing action than rotation (whether about the flossing member's axis or an axis offset therefrom).
In greater detail, the linear drive linkage 32 includes a single elongated link member 60 having a first end operably connected to the drive shaft 46 of the motor 40, and a second end 58 extending from the tip portion 42 of the handle 36 for receiving the tip or flossing member 48. The motor 40 is oriented in the handle 36 to generally rotate the drive shaft 46 about the longitudinal axis of the housing. The linear drive linkage 32 extends at an angle downwardly to follow the shape of the housing. See
As shown in
The first end of the link member 60 can be of any reasonable shape for being received in the similarly-shaped off-center recess in the drive member 62. Preferably, the drive member 62 has a circular or spherical off-center recess 64 formed therein for receipt of the preferably substantially spherically-shaped first end of the link member 60. A ball and socket type of structure is contemplated. It is important that the first end of the link member 60 be tightly held in the recess 64 to minimize noise caused by the relative movement of the drive member and the first end of the link member 60 when the drive member 62 is rotated. Further, the friction between the first end of the link member 60 and the walls of the recess needs to be minimized to reduce wear and tear, and to reduce the energy consumption of the motor.
The link member 60 is divided into two portions, the first portion 63 associated with the first end and the second portion 65 associated with the second end 58. The two halves are generally delineated by a pivot 66. See
A flexible hinge 70 is formed in the link member 60 adjacent to the pivot 66 and in the first portion 63. The flexible hinge 70 has the full dimension of the height of the link member 60 in a vertical direction and is very thin relative to the height of the link member in the side-to-side direction (
The hinge 70, which is flexible, preferably resiliently to automatically be biased back to its original position, in the side-to-side direction (in its thin dimension), and can twist, in combination with the fixed pivot, isolates the vertical motion from the generally rotary motion of the first section 63 of the link member 60. This vertical oscillating motion is transmitted to the second section 65 of the link member 60 to move the flossing tip 48 in a vertical, planar, reciprocating accurate motion.
When the first end of the link member 60 moves up and down as the off-center recess 64 in the drive member 62 moves from top to bottom during rotation, the hinge 70 bends laterally and twists axially, yet the larger (vertical) dimension of the hinge 70 is substantially rigid and thus transfers vertical motion through the pivot point to cause the pivot 66 to rotate or pivot along its horizontal axis This in turn causes the second end 58 of the link member 60 to move through a vertical arc with respect to
The second end 58 of the link member 60 is free to move in the translatory motion inside the housing 34 and outside the housing such that when a tip member 48 is attached to the second end 58 of the link member 60 the tip member also moves in a translatory motion. The flexible hinge section 70 of the link member 60 acts as a living hinge to effectively absorb and isolate the side-to-side or lateral movement and twisting motion of the first end of the link member 60 and allows only the vertical up-and-down movement of the first end of the link member 60 to be transferred through the pivot 66 to the second end 58 of the link member 60 to cause the tip member 48 attached thereto to move up and down in a translatory linear oscillating motion defining an arc. This isolates the vertical movement components from the lateral movement components. The pivot restraint (yokes) 68 also isolates the lateral movement components from the vertical movement components.
Typical cam and follower structures, because of the clearance required, generate significant noise when the motor operates at approximately 9,000 rpm (the desired speed). To reduce this noise, the instant invention employs a ball-shaped first end of the link member 60 to be received in the off-center recess 64 (socket) of the drive member 62. The ball or spherical shape of the first end of the link member 60 can be more tightly toleranced with the off-center recess 64 in the drive member 62 to minimize the clearances and thereby reduce the noise level during operation. A ball and socket structure is shown in
The stroke of the flossing member 48 is thus represented by the plane formed between dashed line ww and yy. Ideally, the motion of the tip of the flossing member 48 is approximately between 0.050 inches to 0.070 inches, at an angle of between 5 and 30 degrees (no angle required if entire flossing tip translates, as described below), and at a speed of 9,000 cycles per second. The flossing member 48 is moved through this stroke efficiently and with reduced noise.
The structure described above with respect to
The cam-followers 88 and 116 of the structures of
Another option to obtain more pure “single plane” oscillation would be to create a “living flex” cantilever beam structure 160 utilizing a subframe 162 in the housing. This could take the eccentric rotational motion from the motor and turn it into “single plane” translatory oscillation. See
Another variation on this structure would be to replace the living flex portion of the mechanism with a slide channel 200 in the subframe of the housing, as shown in
Another embodiment using pure rotary input motion with the motor 40 somewhat remote from the tip 210 would include a track cam 212 attached to the motor shaft 214 with the second end of the link member 216 engaging the track cam 212. See
The linear drive linkage of the present invention efficiently converts pure rotary motion to oscillating translatory motion (pivotal up and down movement through a vertical plane) for effective flossing action in the interproximal gaps between one's teeth. The structures described herein minimize or eliminate any side to side movement of the tip member by isolating the up and down movement from the lateral movements through the drive structure between the rocker arm and the motor drive shaft. Preferably, a combination horizontal pivot and vertically oriented flexible section of the rocker arm are used in combination to isolate the up and down vertical motion and eliminate the side to side or lateral motion.
The second end of the link member is designed to receive the tip member. Preferably, the tip member is both securely attached to the second end of the link member, yet can be easily released therefrom for replacement.
Adjacent the closed end 256 of the tip cap a keying feature 264 is formed on the lower side walls thereof. See
The secondary key is necessary where the tip is curved and thus has a proper up and down orientation. A preferred keying feature 276 is defined near the second end 270 of the link member 272 to mate with the secondary keying feature 264 inside the tip cap 252. This secondary keying feature allows the tip cap 252 to be positioned in only one orientation on the second end of the link member in the event the flossing element is curved and requires a particular orientation for proper use. The secondary keying feature is not required unless the particular orientation of the tip cap 252, when mounted on the second end of the link member, is desired. Other types of secondary keying features can be used, including other geometrical shapes, notches and grooves, or the like, to allow an engagement of the keying features for insertion of the second end of the link member into the tip cap. The preferred secondary keying feature described herein is preferred because of its ease of manufacture and simplicity.
A sealing surface 280 is defined on the second end 270 of the link member 272 spaced away from the latch tabs 274 and on the side of the latch tabs away from the free end of the link member. The rim of the tip cap 252 engages the sealing surface 280 (which can be an annular boss formed around the link member).
FIGS. 18A-E shows an alternative embodiment of the second end of the link member not requiring a keying feature. The link member is similar to that shown in
In operation the enclosed latching recess 260 in the tip cap 252 engages the latching tabs 272 on the mechanism (the second end of the link member) to hold the tip in place. The keying feature prevents the tip from being installed in the improper orientation if that feature is desired. The tip is disengaged from the second end of the link member by compressing the sides of the tip cap 252 to deform it into essentially an elliptical shape. This would create a major axis of an ellipse which would be larger than the distance across the latching tabs 272 on the second end of the link member. The tip could then be easily removed because the latch tabs disengage from the latch grooves when the sidewalls are squeezed.
A tip-holding cartridge could provide the compression means for insertion or removal without the user having to directly contact the tip. There is a gap formed on either side of the second end of the link member when inserted in the tip cap to allow the tip cap to be squeezed to form an elliptical shape. The tip cap can deformed to an ovalized or non-circular shape to release the latch tabs 272 from the latch recesses 260.
This detent-style tip connection allows for secure placement of the tip member on the second end of the link member yet also allows for convenient removal of the tip member from the second end of the link member. When the tip member is positioned on the second end of the link member, an audible “click” is heard when the tip member is correctly seated thereon. This is a positive feature for assuring the user that the tip member is firmly attached to the device.
The latch tabs 274 can have at least a sloped front surface 290 (see
The tip can be removed from the second end of the link member by squeezing the sides of the tip that are offset approximately 90 degrees from the engagement of the latch members 274 with the latch recesses 260 in the tip cap 252. Compressing the tip cap 252 at this location causes the tip cap to form an elliptical or oval shape, disengaging the latch tabs from the latch recesses 260 and allows the tip cap 252 to be removed from the device. This can be done by hand, with a tool, such as pliers, or by the tip removal device shown in
The first end 306 of the slot 304 has a substantially circular shape to allow the insertion of the tip 250 therethrough. The upper edges 308 of the slot 304 slope outwardly at the first end 306 and gradually transition to a vertical orientation about half way between the first end 306 and the second end 310 of the slot. The seal collar 280 (
At the second section 314 of the slot 304A, a second downwardly sloping ramp 318 (
The automatic removal of the flosser tip from the end of the device is a convenience to allow the user to easily replace the tips by sliding the second end of the link member along the slot, removing the tip member and easily replacing the tip by simply inserting it into a new flosser tip stored adjacent to the slot.
While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various other changes in the form and details may be made without departing from the spirit and scope of the invention.
Claims
1. A connection structure formed on an interproximal flosser; comprising:
- a link member;
- a first latch tab formed on a first portion of the link member;
- a second latch tab formed on a second portion of the link member, the second latch tab diametrically opposite the first latch tab; and
- an orientation structure formed on the link member; wherein
- the orientation structure facilitates connection of the connection structure to a tip when the tip and the connection structure are properly oriented with respect to one another.
2. The connection structure of claim 1, wherein the tip is a flossing element.
3. The connection structure of claim 1, the orientation structure comprising a first key.
4. The connection structure of claim 3, wherein:
- the first key imparts a rectangular cross-section to the link member; and
- the first key facilitates connection of connection structure to the tip only when the tip is oriented in one of a first or second position.
5. The connection structure of claim 4, wherein:
- the tip comprises a blade having a first axis and a second axis;
- the link member oscillates the tip; and
- the first and second positions correspond to the tip oscillating along the first axis.
6. The connection structure of claim 5, wherein the tip is curved.
7. The connection structure of claim 5, wherein the tip is straight.
8. The connection structure of claim 1, wherein the orientation structure comprises a pie-shaped structure.
9. The connection structure of claim 1, the orientation structure comprising:
- a first key; and
- a second key cooperating with the first key to facilitate connection of the connection structure to the tip.
10. The connection structure of claim 9, wherein the tip is curved.
11. The connection structure of claim 9, wherein the second key cooperates with the first key to accept the tip in a single orientation.
12. The connection structure of claim 11, wherein the second key comprises a first arcuate groove extending from a distal end of the link member at least partially along a longitudinal axis of the link member.
13. The connection structure of claim 11, wherein the second key further comprises a second arcuate groove extending from a distal end of the link member at least partially along a longitudinal axis of the link member, formed on a side of the link member opposite the first arcuate groove.
14. The connection structure of claim 11, wherein the second key comprises a geometrical shape formed on the link member.
15. The connection structure of claim 14, wherein the geometrical shape extends into the link member.
16. The connection structure of claim 1, further comprising a sealing surface formed on the link member, the sealing surface spaced away from the first and second latch tabs and operative to engage a rim of the tip when the tip is connected to the link member.
17. A connection structure formed on an interproximal flosser;
- comprising:
- a link member;
- a first latch tab formed on the link member;
- a second latch tab formed on the link member;
- the first latch tab comprising a first sloped front surface;
- the second latch tab comprising a first sloped front surface; wherein
- the first and second sloped front surfaces permit attachment of a tip to the connection structure.
18. The connection structure of claim 17, wherein:
- the tip is configured to accept the link member therein;
- the tip comprises: a generally circular, deformable sidewall having an exterior and an interior; a first latching recess formed in the interior of the sidewall; and a second latching recess formed in the interior of the sidewall;
- the tip is configured to deform as it passes over the first and second latch tabs;
- the tip is further configured to accept the first latch tab in the first latching recess and the second latch tab in the second latching recess; and
- the tip is further configured to rebound to an original shape upon accepting the first and second latching tabs.
19. The connection structure of claim 18, wherein the link member comprises:
- a generally flat front wall;
- a generally flat first sidewall perpendicularly offset from the front wall;
- a generally flat second sidewall perpendicularly offset from the front wall;
- a first angled wall connecting the front wall to the first sidewall; and
- a second angled wall connecting the front wall to the second sidewall.
20. A method for attaching a tip to a connection structure of a flossing device, comprising:
- inserting a link member of the flossing device into an interior of a tip;
- aligning a first latch tab with a first latching recess;
- aligning a second latch tab with a second latching recess; and
- aligning a key formed on the link tab with a corresponding recess formed in the tip; wherein
- the tip may be connected to the connection structure only when the key and recess are aligned.
Type: Application
Filed: Aug 11, 2005
Publication Date: Dec 1, 2005
Inventors: Gary Sokol (Longmont, CO), Cliff Snyder (Fort Collins, CO)
Application Number: 11/202,473