Abstract
Powder chamber for an air polishing device, extending from a top end to a bottom end along an axis, said powder chamber including at least two wall sections, where a first wall section forms a first angle with respect to the axis, and wherein a second wall section forms a second angle with respect to the axis, wherein the angles are measured in a measuring direction from the axis to the appropriate wall section in such a manner so that the acute angles are obtained, wherein the measuring direction) from the top end to the bottom end is counted positive, and wherein the measuring direction from the bottom end to the top end is counted negative, wherein the second wall section is arranged below the first wall section, and wherein the second angle is smaller than the first angle.
Claims
1. Powder chamber for an air polishing device, extending from a top end to a bottom end along an axis, said powder chamber comprising at least two wall sections, wherein a first wall section forms a first angle with respect to the axis, and wherein a second wall section forms a second angle with respect to the axis, wherein the angles (.sub.11, .sub.12) are measured in a measuring direction from the axis to the appropriate wall section in such a manner so that the acute angles are obtained, wherein the measuring direction from the top end to the bottom end is counted positive, and wherein the measuring direction from the bottom end to the top end is counted negative, wherein the second wall section (12) is arranged below the first wall section, and wherein the second angle is smaller than the first angle.
2. Powder chamber according to claim 1, comprising a third wall section that forms a third angle with respect to the axis, wherein the third angle is bigger than the second angle, and wherein the third wall section is arranged below the second wall section.
3. Powder chamber according to claim 1, wherein the first wall section is inclined towards the axis forming a first angle >0.
4. Powder chamber according to claim 2, wherein the first angle and/or the third angle is at least 15.
5. Powder chamber according to claim 1, wherein the second angle is about 0.
6. Powder chamber according to claim 3, wherein a volume of the powder chamber, limited by the third wall section, is less than 25% of a complete volume of the powder chamber.
7. Powder chamber according to claim 1, wherein a length of the second wall section is at least about 5 mm.
8. Powder chamber according to claim 7, wherein a ratio between the length of the second wall section and a length of the third wall section is less than 1.
9. Powder chamber according to claim 7, wherein a ratio between a length of the first wall section and the length of the second wall section is bigger than 1.
10. Powder chamber according to claim 1, wherein the powder chamber is rotation symmetric.
11. Powder chamber according to claim 1, wherein the top end comprises a sealing portion.
12. Powder chamber according to claim 1, wherein the bottom end comprises an air inlet.
13. Powder chamber according to claim 1, wherein a venturi tube is arranged in or at the powder chamber.
14. Air polishing device comprising a powder chamber according to claim 1.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0039] Additional advantages and features of the current invention are shown in the following description of preferred embodiments of the current invention, with reference to the attached drawings. Features and characteristics of respective embodiments are explicitly allowed to be combined within the scope of the current invention.
[0040] FIG. 1: shows the measuring scheme that is used to define the angles;
[0041] FIG. 2: shows two working principles of air-polishing devices;
[0042] FIG. 3: shows a powder chamber comprising a first and a second wall section;
[0043] FIG. 4: shows a powder chamber comprising three wall sections;
[0044] FIG. 5: shows a further embodiment of a powder chamber comprising three wall sections;
[0045] FIG. 6: shows a container comprising a powder chamber with three wall sections;
[0046] FIG. 7a: shows a powder chamber, in particular a bottom end;
[0047] FIG. 7b: shows a powder chamber comprising a bottom plate;
[0048] FIG. 8: shows a perspective view of an air-polishing device.
DETAILED DESCRIPTION
[0049] FIG. 1 shows the measuring scheme used to define the angles. An axis c is shown that extends from a top end t to a bottom end b of a powder chamber (not shown). A first wall section 11 and a second wall section 12 extend along the axis c. The wall sections are only used by way of example to explain a measuring direction md. First angles all are measured from the axis c to the wall section 11, so that the acute angle is obtained. The same applies to second angles .sub.12 that are formed between the second wall section 12 and the axis c. If the measuring direction is directed from the top end t to the bottom end b, the angles are counted positive. If the measuring direction md is directed from the bottom end b to the top end t, the angles are counted negative. Positive angles reach from 0 to <90, negative angles reach from 0 to >90.
[0050] FIG. 2 shows two working principles of air-polishing devices, in particular of powder chambers 10. The powder chambers 10 are filled, for example, with powder 1, such as sodium bicarbonate powder, which is steered up by pressurized air. The pressurized air gets into the powder chambers 10 via air inlets 20. An air/powder-mixture is transported via outlets 30, for example through a tube to a nozzle where water is added. In the left design of FIG. 2, air and powder are mixed by combination of carburetor technique and swirling. Therefore, a venturi tube 83 is located within the powder chamber 10. In the other type (shown right) the air/powder-mixture is created by swirling only.
[0051] FIG. 3 shows a powder chamber 10 that extends along an axis c from a top end t to a bottom end b. The powder chamber 10 comprises a first wall section 11 and a second wall section 12. The first wall section 11 forms a first angle .sub.11 with the axis c. The second wall section 12 forms a second angle .sub.12 with the axis c. The first angle is, according to one embodiment, at least 20, preferably at least about 27. The second angle is smaller, as can be seen from FIG. 3. This provides more space for the powder that is located within the powder chamber. Along the axis c, the first wall section 11 has a length l.sub.11 and the second wall section 12 has a length l.sub.12 which form appropriate volumes.
[0052] FIG. 4 shows a powder chamber 10 similarly to that known from FIG. 3. However, the powder chamber 10 comprises also a third wall section 13. A second wall section 12 is basically parallel orientated with respect to an axis c forming a pit. In other words, a second angle .sub.12 is basically 0 and thus smaller as a first angle .sub.11 of the first wall section 11. A third angle .sub.13 of the third wall section 13 is bigger than the second angle .sub.12 of the second wall section 12. The wall sections 11, 12 and 13 extend along the axis c from a top end t to a bottom end b and have a length l.sub.11, l.sub.12 or l.sub.13, forming/defining appropriate volumes. FIG. 4 shows a double cone-design. The first and the third angles .sub.11, .sub.13 are at least about 20, preferably at least about 25 or at least about 27. This means that an angulation of the cones is at least about 50, preferably at least about 55.
[0053] FIG. 5 shows a further embodiment of a powder chamber 10 comprising three wall sections 11, 12, 13 extending along an axis c from a top end t to a bottom end b. The first wall section 11 forms a first angle .sub.11 with respect to the axis c. The first angle .sub.11 is bigger than 0 thus forming a first cone. A second angle .sub.12 of the second wall section 12 is smaller than the first angle .sub.11. In particular, the second angle .sub.12 is negative whereby self-blockade can be prevented very effectively. A third angle .sub.13 formed by the third wall section 13 is bigger than the second angle .sub.12. Actually, the third angle an is again positive (forming a second cone), similar to the first angle .sub.11 whereby a very small third volume is formed which optimizes the emptying-behavior and which reduces the residual powder left within the powder chamber 10.
[0054] FIG. 6 shows a container 80 as it is used in air-polishing devices. Within the container 80 a powder chamber 10 is arranged. The powder chamber 10 comprises a first wall section 11, a second wall section 12 and a third wall section 13. The powder chamber 10 extends along an axis c from a top end t to a bottom end b. The top end t of the powder chamber 10 comprises a sealing portion 40 which seals in particular the first wall section 11 with respect to the container 80. The bottom end b of the powder chamber 10 comprises an air inlet 20. In the embodiment shown in FIG. 6, the top end t of the powder chamber 10 is adapted to arrange an insert 82. The insert 82 comprises a venturi tube 83. An outlet 30 is adapted to bring/conduct an air/powder-mixture to an air polishing device (not shown). Expediently, the walls of the third wall section 13 do not converge into an apex. Instead, a flat bottom plate 14 is formed which is adapted to avoid blocking of the air inlet 20 due to the powder which is in the powder chamber 10. FIGS. 7a and 7b deal with this aspect in a more detailed way.
[0055] FIG. 7a shows a powder chamber 10, in particular a bottom end b and a third wall section 13. An air inlet 20 extends into the powder chamber 10, in particular into the volume formed by the third wall section 13. A distance l.sub.22 which extends between the bottom end b and a nozzle 22 of the air inlet 20 lies preferably within a range of about 1 to 5 mm. This prevents the air inlet 20 or the nozzle 22, respectively, from plugging/blocking with powder.
[0056] FIG. 7b shows a powder chamber 10, similar to the one shown in FIG. 7b. However, at a bottom end b a bottom plate 14 is formed. A diameter d.sub.14 lies according to some embodiments within a range of about 3 to 25 mm, preferably within a range of about 4 to 20 mm, in particular within a range of about 10 mm. The bottom plate 14 avoids blocking/plugging of the air inlet 20 or the nozzle 22, respectively. As can be seen from FIG. 7b, the nozzle 22 extends also a little bit into the volume formed by a third wall section 13. This increases the effect of the bottom plate 14.
[0057] FIG. 8 shows by way of example an air polishing device 90 comprising two containers 80 that are arranged at a basic device of the air polishing device 90. A flexible tube 92 is arranged at the basic device. The flexible tube 92 ends in a hand sample 94 that includes a nozzle 96. Preferably, the container 80 can be easily removed if a (inserted) powder chamber is empty. Alternatively, only the powder chamber that is arranged within the container may be removed to insert a new (full) one.
