Atomizer with improved wire type atomizing element support and method of making same

[0001] 1. Field of the Invention

[0002] This invention relates to atomization devices and more particularly it concerns improvements by which atomization elements are supported in such devices

[0003] 2. Description of the Related Art

[0004] U.S. Pat. No. 5,283,496 shows a crystal resonator which is supported by electrically conductive wires

[0005] U.S. Pat. No. 4,087,495 shows an ultrasonic vibrator assembly which is suspended by means of wire-like stays.

[0006] U.S. patent application Ser. No. 10/154,509, filed on May 24, 2002, and assigned to the assignee of the present invention, discloses an atomization device in which an atomizing assembly comprising a domed orifice plate and an annular piezoelectric actuator, are held in a retainer which in turn is supported by a wire loop. The loop is fitted over support posts and thereby supports the atomizing assembly over a wick which brings liquid to be atomized up from a bottle or reservoir. The wire loop is formed by bending a length of wire to a loop shape and then welding the ends of the wire together to complete the loop.

[0007] This invention provides an improved atomizing assembly support which is easier to manufacture and assemble in the atomizing device and which eliminates the need to weld a wire to form a support loop.

[0008] In one aspect, this invention provides a novel wire support for a piezoelectric actuator and atomizer element vibrated by the actuator. According to this aspect there is provided a novel liquid atomizer which comprises an actuator, an atomizing element, a retainer, a base member, mounting posts and at least one support wire. The atomizing element is connected to the actuator to be vibrated thereby; and the actuator and atomizing element in turn are held by the retainer. The base member is generally horizontal with an opening therein and it is constructed to hold, beneath the opening, a bottle which contains a liquid to be atomized. The mounting posts extend up from the base member above and alongside the opening. A support wire extends from the retainer up to and is wound around the mounting posts to hold the retainer with the actuator and the atomizing element suspended above the opening.

[0009] In another aspect the invention involves a novel method of forming an atomizing device. According to this aspect there is provided an actuator with an atomizing element which is connected to be vibrated by the actuator and a retainer to hold the actuator and the atomizing element. There is also provided a generally horizontal base member having an opening therein and constructed to hold, beneath the opening, a bottle which contains a liquid to be atomized. The base member includes a plurality of mounting posts which extend up above and alongside the opening. At least one support wire is provided to extend from the retainer; and the support wire is wound on a mounting post to hold the retainer with the actuator and the atomizing element suspended above the opening.

[0015] As shown in FIG. 1, an atomizer device 10 comprises a hollow shell-like outer cover 12 which contains a generally horizontal internal chassis 14. The chassis 14 is formed with an opening 16 and a reservoir or bottle 18 containing liquid to be atomized is mounted on the underside of the chassis below the opening 16. A battery holder 20 formed on the lower side of the internal chassis 14.

[0016] As shown in FIG. 2, a plurality of mounting posts 22a, 22b, 22c and 22d extend upwardly from the chassis 14 and are distributed around the opening 16. An atomizing assembly 24 is mounted on the chassis above the opening 16 by means of a support wire 26 which is looped about and extends from the mounting posts 22a, 22b, 22c and 22d to the atomizing assembly 24. A printed circuit board 28 is mounted on the upperside of the chassis 14. This printed circuit board is provided with electrical circuits which are connected to be powered by batteries in the battery holder 20 and which are configured to produce energization voltages for the atomizing assembly 24. These voltages are communicated via electrical lines 29 to a ring-shaped piezoelectric actuator 30 (FIG. 1) in the atomizing assembly 24 where they impose alternating electrical fields across the thickness of the actuator and cause it to expand and contract in radial directions. An orifice plate 32, which is formed in a center region thereof with minute orifices, is secured to and extends across a center opening in the actuator 30. The radial expansion and contraction of the piezoelectric actuator 30 causes it to push the center region of the orifice plate 34 up and down in a vibratory manner. During this vibratory movement liquid from the bottle 18 is delivered by a capillary element or wick 36 up to the underside of the orifice plate 32. The up and down movement of the plate drives the liquid through its orifices so that the liquid becomes separated into small liquid droplets which are then ejected in the form of a mist out through an opening 38 in the outer cover 12.

[0017] The construction of the atomizing assembly 24 is shown in the exploded view of FIG. 3. This assembly includes a retainer 40, a coil compression spring 42, the piezoelectric actuator 30 and the orifice plate 32. The retainer is made of plastic and has a hollow cylindrical body 44. An upper rim (not shown) extends inwardly at the upper end of the body 44 and a pair of lower flanges 46 extend downwardly from its lower end. Each of the flanges 46 is formed with an elongated circumferentially extending slot 48. In assembling the subassembly 24, the coil compression spring 42 is inserted into the bottom of the retainer 40 and pushed up against its not shown upper rim. The piezoelectric actuator 30 with the orifice plate 32 soldered thereto is then pushed up against the spring 42 until the actuator 30 is located above the slots 48. Then the support wire 26 is squeezed inwardly in the direction of the arrows A, A so that projections 26a thereon can fit between the lower flanges 46. The projections 26a are aligned with the slots 48 and allowed to spring back to their normal configuration upon release of the squeezing force on the wire 26. This allows the projections 26a to become inserted into the slots 48 where they are held by the resilient characteristics of the support wire 26. Further, the portions of the wire support 26 adjacent the projections 26a extend into the retainer 40 and support the piezoelectric actuator 30 and the orifice plate 32 against the force of the coil spring 42.

[0018] The support wire 26, with the atomizing subassembly 24 thus secured thereto, is then mounted on the atomizer device by looping the support wire over upper cylindrical portions 22e, 22f, 22g and 22h of the mounting posts 22a, 22b, 22c and 22d, respectively, as shown in FIG. 2. The support wire 26 is held in place by detents 23 formed in the upper cylindrical portions of the mounting posts.

[0019] The support wire 26 is made of thin resilient material such as metal. A preferable material is type 302 or type 304 stainless steel wire having a diameter of 0.020 inches (0.5 mm). These are not critical criteria. If is sufficient that the support wire be strong enough to support the atomizing subassembly 24 and that it be thin enough to minimize migration of any liquid that may become deposited thereon. The material of the support wire 26 should also retain its resiliency when bent to insert the projections 26a into the retainer 40 so that they will spring back and become inserted and held in the slots 48 in the retainer body 44.

[0020] As shown in FIG. 4, the support wire 26 is a single piece which is bent to form a central portion 26b and two side portions 26c. The side portions 26c extend at an angle α of 65° relative to the central portion 26b. This angle may range between 60° and 70° although a range of 62.5° to 67.5° is preferable. The projections 26a are formed in the middle of the side portions 26c and project outwardly. As can be seen from FIGS. 2 and 3, the dimensions of the projections 26a are such that they can fit into the slots 48 in the retainer body 44.

[0021] It will be noted that a partial loop is formed at the intersections of the central portion 26b and the side portions 26c of the wire support 26. This partial loop extends out from the retainer 40 and can be fitted over the upper cylindrical portions 22g and 22h of two of the mounting posts 22c and 22d. The free ends of the side portions 26c of the wire support 26, which also extend out from the retainer 40, are bent into partial loops 26d. These partial loops have a diameter which permits them to fit closely over the upper cylindrical portions 22e and 22f of the other mounting posts 22a and 22b.

[0022] FIG. 5 shows the support wire 26 bent so that the projections 26a fit inside the retainer body 44. This bending takes place in the regions where the side portions 26c join the central portion 26b. When the wire is released and the projections 26a fit into the slots 48 of the retainer body 44, the regions where the side portions 26c join the central portion 26b are dimensioned to fit over the upper cylindrical portions 22g and 22h of the mounting posts 22c and 22d (FIG. 2). Also the partial loops 26d are positioned to fit over the upper cylindrical portions 22e and 22f of the mounting posts 22a and 22b. Thus the atomizing subassembly 24, including the wire support 26 can easily be fitted onto the mounting posts of the chassis 14 and held in place by the detents 23 on the posts.

[0023] By means of the wire support described herein, it is not necessary to form the wire support into a complete loop. Consequently it is possible to eliminate welding and thereby facilitate and reduce fabrication expenses of an atomizer device.