Cyclonic separation device with acceleration ramp

B.0955¹

CYCLONIC SEPARATION DEVICE WITH ACCELERATION RAMP

The invention relates to a body defining a cyclonic chamber, which we will simply call “bowl”, of a device for separating by inertia or cyclone the dust and waste present in an air flow. It is particularly suitable for use for a vacuum cleaner. It also relates to a cyclonic separation device and a dust vacuum cleaner as such comprising such a bowl.

A first type of dust and waste collection device for vacuum cleaners of the state of the art consists of a filter in the form of a paper bag, interposed between an inlet tube for an air flow. , comprising dust and waste sucked from a surface to be cleaned, and a motor-fan unit. The drawback of this solution stems from the fact that the paper filter bag ends up filling up and requires its replacement, which represents an unpleasant and costly maintenance operation for the user. In addition, the filling of the bag is done to the detriment of the performance of the vacuum cleaner since it results in a loss of its power.

In order to remedy these drawbacks, a second type of dust and waste collection device of the state of the art is based on a cyclonic or inertial type separation of this dust and waste. In such a device, an air flow is conducted in a cyclonic separation chamber where it continues a vortex path favorable to the separation of the waste. Indeed, the heaviest waste is separated from the main air flow by the centrifugal effect of the vortex flow. Then, the air flow is evacuated from the cyclonic chamber through a cylindrical grid fitted on a separator filter placed in the center of this chamber, which represents a second additional operation of filtering the waste, generally retaining dust at this stage. . Finally, the dust and waste remain trapped in a storage area set up in the lower part of the cyclone chamber. It is then sufficient to empty them from time to time by simply dumping them into a trash can, via a trap fitted in this storage chamber.

Such a cyclonic separation device can be coupled to a canister-type vacuum cleaner, also comprising a collection bag, as described in documents FR2817138 and FR2848090.

As a variant, such a cyclonic separation device can be used alone, as is particularly the case for low-power vacuum cleaners whose frame is integrated into a rigid handle directly handled by an operator, generally called “broom” vacuum cleaners, as described in EP1611829.

The performance of cyclonic separation devices depends on many parameters such as the speed and direction of the inlet air flow, the quality of the vortex path in order to operate the centrifugal separation of the waste and prevent a part of the flow from polluted air does not pass through the separator grid before the centrifugal discharge of its waste ...

The existing solutions are not entirely satisfactory and the general object of the invention is to provide an improved solution for the separation of the cyclonic type of waste from an air stream sucked in by a vacuum cleaner.

The present invention is achieved with the aid of a device for the cyclonic separation of waste and dust for a vacuum cleaner, comprising a substantially cylindrical interior cyclonic chamber accessible by an air inlet, as well as a separating filter housed in the part. central of the inner chamber, characterized in that it comprises a portion of pipe to conduct an air flow towards the air inlet, this pipe portion being disposed around the substantially cylindrical interior cyclonic chamber, from an initial point to an end point near the air inlet, the section of this pipe portion towards the end point being smaller than its section towards the initial point so as to form an acceleration ramp for the air flow between these two points.

Such an acceleration ramp associated with the separation chamber makes it possible to avoid an excessively large architecture of said chamber by dissociating this acceleration function from the chamber itself. In other words, for a chamber of determined size, this ramp makes it possible to improve the efficiency of separating dust and waste by increasing their speed. This aspect is all the more important when the device is used in a vacuum cleaner where the motors are small and generate relatively low flow rates, such as the motors of vacuum cleaners of the broom type, some of which operate on batteries.

Advantageously, the portion of pipe for conducting the air flow towards the air inlet of the cyclonic chamber travels at least a quarter of a turn around the cyclonic chamber, so that the speeds are significantly increased compared to the absence such a portion of pipe.

Preferably, the portion of pipe for conducting the air flow towards the air inlet of the cyclone chamber travels at least two-fifths of a turn around the cyclonic chamber, which makes it possible to have a more homogeneous flow, while by allowing a more gradual acceleration of the flow.

Furthermore, the portion of pipe for conducting the air flow towards the air inlet of the cyclonic chamber is substantially horizontal.

Advantageously, the pipe portion for conducting the air flow towards the air inlet of the cyclonic chamber is connected to a vertical pipe portion whose section decreases, seen in the direction of air circulation. This vertical duct thus also participates in the acceleration of the flow, and makes it possible to achieve this acceleration over a considerable length, this slow progression of the acceleration of the air flow limiting the turbulence and therefore the associated noise.

According to a preferred embodiment of the invention, the cyclonic separation device comprises a removable bowl delimiting the cyclonic chamber, the bowl carrying the portion of pipe to conduct the air flow towards the air inlet of the cyclonic chamber.

This architecture facilitates cleaning of the separation device, while rationalizing manufacturing and assembly costs.

More precisely, the bowl comprises a tubular body with a cylindrical outer lateral surface delimiting the cyclonic chamber, the portion of pipe for conducting the air flow towards the air inlet of the cyclonic chamber being fixed in contact with the outer lateral surface. cylindrical of the tubular body of the bowl.

In an alternative embodiment, the pipe is formed by a double rib on the bowl closed by the wall in correspondence of the housing receiving the bowl. The pipe thus comes essentially from the housing receiving the bowl.

The present invention also covers embodiments where the pipe is formed partly on the bowl and partly on the housing receiving the bowl.

Advantageously, the bowl comprises an inclined and articulated lower part forming a door in order to facilitate the emptying of the bowl and its cleaning.

The present invention also relates to a dust vacuum cleaner comprising a device for cyclonic separation of dust and waste according to one of the characteristics stated above.

Advantageously, the vacuum cleaner is a stick vacuum cleaner comprising a housing arranged in its handle to receive the cyclonic separation device according to one of the previously stated characteristics where the bowl is removable, this housing comprising a first connection in its lower part connected to a vertical pipe portion of the bowl and a second connection in its upper part connected to the outlet of the cyclonic separation device.

These objects, characteristics and advantages of the present invention will be explained in detail in the following description of a particular embodiment made without limitation in relation to the accompanying figures, among which:

FIG. 1 represents an overall perspective view of a stick vacuum cleaner according to one embodiment of the invention.

FIG. 2 represents an exploded view of a cyclonic separation device according to the embodiment of the invention.

FIG. 3 represents a perspective view of the bowl of the cyclonic separation device according to the embodiment of the invention.

FIG. 4 represents a top view of a section along a horizontal plane P at the level of the acceleration ramp of the bowl of the cyclonic separation device according to the embodiment of the invention.

FIGS. 5 and 6 represent two perspective views from two different angles of the cyclonic separation device according to the embodiment of the invention.

FIG. 7 represents a side view of a separator of the cyclonic separation device according to the embodiment of the invention.

FIG. 8 represents a side sectional view of the separator of the cyclonic separation device according to the embodiment of the invention.

FIG. 9 represents the housing of the frame of the vacuum cleaner to receive the cyclonic separation device according to the embodiment of the invention.

Figure 1 shows a stick vacuum cleaner 1, comprising a triangular nozzle 2 connected to a handle 4 by means of an intermediate connecting part 3. By the term handle is meant here, not only a longilinear part of the device. terminated by a handle 8 at its upper end, but also various elements associated with the elongated part forming a frame, comprising a battery 5, a motor 6, and a device for separating and storing 7 waste.

For the following description, we define the direction z as the axis of the handle 4 of the vacuum cleaner, corresponding to a substantially vertical axis in the rest position of the vacuum cleaner shown in Figure 1, the longitudinal axis x as l 'axis perpendicular to the z axis passing through the handle 4 from rear to front in its plane of symmetry, and the transverse y axis perpendicular to the x and z axes. In the rest position of the vacuum cleaner, the x and y axes will therefore be in a substantially horizontal plane. This mark can be tilted when the handle is tilted. However, for reasons of simplification of the following description, we will call z the vertical direction, x the longitudinal horizontal direction and y the transverse horizontal direction, implying a description made when the vacuum cleaner is in its rest position or when the device cyclonic separation 7 is positioned vertically.

The invention relates in fact to the device for separating and storing waste, an exploded view of which is shown in FIG. 2, which consists of an outer body, which we call bowl 10, within which a separator filter is housed. 20. A foam filter 30 is positioned in the upper part of the separator filter 20. Finally, the cyclonic separation device is closed by a cover 31, comprising a circular opening 32 for the top discharge of the clean air flow after its treatment by the cyclonic separation device 7. This device, once assembled, is positioned in a housing 35 arranged in the handle 4 of the vacuum cleaner.

The bowl 10 is in the form of a substantially cylindrical body, particularly visible in Figures 3 to 5, comprising an inlet 13 in its upper part, visible in Figure 4, connected to an inlet pipe, which leads the air flow from the nozzle to a substantially cylindrical interior chamber 19 of the bowl 10. This inlet pipe, linked to the bowl 10, comprises a first substantially vertical portion 11, forming an elbow in its upper part, followed by a second substantially horizontal portion 12, forming an acceleration ramp 40 for the air flow, visible in Figure 4, which thus enters the inner chamber 19 of the bowl with a speed and direction adapted to the formation of a vortex flow.

Furthermore, the first vertical portion 11 advantageously has a reduction in section from the lower part towards the upper part connected to the portion 12, also in order to achieve an acceleration of the flow.

Indeed, the reduction in section on the vertical portion 11 is at least 30% between the inlet of the duct and its connection with the portion 12.

In addition, the elbow has been dimensioned, in particular at the level of its radii of curvature at the junction of the portions 11 and 12, to limit turbulence during the straightening of the air flow. In particular, angular areas conducive to the flow stalling, sources of aeraulic disturbance, have been avoided.

The lower face of the bowl 10 is closed by a door 14 articulated by a hinge 15, making it possible to empty the dust and waste accumulated in the lower part 16 which serves as a storage area. The door 14 has an inclination of about 45 degrees with respect to a horizontal plane. This inclination makes it possible to reduce the speed of the vortex flow in the lower storage part 16 of the bowl, thus allowing less disturbed storage of the waste, limiting their rise. Such an inclination could be between 20 and 50 degrees to give suitable results.

According to an essential element of the invention, the acceleration ramp 40 formed by the horizontal portion of the pipe 12 travels at least a quarter of a turn around the inner chamber 19 of the bowl 10, preferably at least two fifths of a turn, in order to to include a sufficient length for the acceleration of the incoming air flow. On this length, which starts from an initial point 41 at the level of the elbow between the vertical 11 and horizontal 12 portions of the inlet pipe, up to an end point 42 where the horizontal portion 12 opens onto the inlet 13 provided in the cylindrical chamber 19, the section of the pipe 12 gradually decreases in order to induce the acceleration of the air flow. Between points 41 and 42, the section is reduced by at least 30%, i.e. a section reduction greater than 50% between the lower part of the portion 11, as visible in FIG. 3, and point 42 opening into the chamber 19.

When the air flow arrives at the end 42 of the acceleration ramp 40, the air flow continues its course along an extension 43 of the outer wall of the portion of pipe 12, from sort of ending up in the inner chamber 19 of the bowl in a direction tangential to this chamber.

According to the embodiment described, the reduction of the section of the pipe portion 12 to form the acceleration ramp 40 is progressive. This acceleration ramp could however have other geometries, other shapes of circular, elliptical, ovoid, or rectangular section ...

In addition, the reduction of this section could be obtained according to different approaches, linear or non-linear, continuous or discontinuous. This pipe portion can be manufactured by assembling two separately molded half-pipes then assembled by welding.

Furthermore, this portion of pipe may be the union of two half-pipes, one being placed on the bowl, in correspondence with an indentation at the bottom of the housing 35 forming the second half-pipe.

Finally, the pipe portion 12 may not be horizontal, but inclined downwards or upwards. The portion of pipe 12 forming the acceleration ramp is therefore arranged around the lateral wall outside the main body of the bowl delimiting the interior chamber 19 of the bowl 10, which makes it possible to form an acceleration ramp without modifying the geometry of this. main body of the bowl or of the inner chamber 19, and without encumbering its upper part dedicated to the discharge of the treated air flow.

The portion of pipe 12 forming the acceleration ramp preferably remains in contact with the lateral outer wall of the main body of the bowl 10 to limit the overall size of the bowl 10 while promoting the stable maintenance of the portion of pipe forming the ramp. acceleration, since it can be fixed over its entire length to the bowl 10, or even simply remain in support to reduce its vibrations. This main body of the bowl 10, delimiting the inner chamber 19, has been shown as a tubular body, having a cylindrical outer wall as well as a cylindrical inner wall defining the inner chamber 19. However, the outer wall of this body could have d 'other forms. Likewise, the inner wall could have a different shape, with a variable circular section, or even an elliptical or ovoid section.

FIGS. 5 and 6 illustrate the assembled cyclonic device, the separator filter being integrated into the central part of the interior chamber 19 of the bowl 10. Its operation will now be explained. The polluted air flow, that is to say comprising dust and waste, coming from the nozzle 2 of the vacuum cleaner, rises through the tube portions 11, 12 to the inlet 13 of the bowl 10, in which it enters with an appropriate speed and direction thanks to the acceleration generated by the acceleration ramp 40. A ramp 23 and more exactly its lower surface 25, which will be described later, forms an upper surface for guiding the flow, which will therefore be driven downwards under this surface 25, according to a helical movement, in the space delimited by the grid 21 and the side wall of the bowl 10 within the inner chamber 19 of the bowl 10 which is also called the cyclonic chamber 19. This swirling movement will continue to the bottom of the bowl 10, the waste being progressively propelled towards the side walls of the bowl 10 under the effect of centrifugal force, before falling into the storage zone 16 represented by the lower part of the bowl 10. The air flow arriving at the bottom of the bowl 10 reverses its direction and rises in the central part of the device, under the grid 21, in an ascending swirling movement, before going up along the side walls of the grid 21 to finally s 'escape through areas of openings 22 made in the side wall of the grid 21 to go up inside this filtering grid 21. During this upward journey, the last small dust still present in the flow will be blocked either in the volume 26 under the grid 21, or by the openings 22 of the grid 21.

FIG. 7 illustrates the upper part of the separator filter 20, which comprises in its upper part a cylindrical cap 27 of diameter corresponding substantially to the diameter of the upper part 17 of the bowl 10, in order to ensure a tight mechanical connection between these two elements when 'they are assembled, as shown in figure 6. Tabs 28 arranged on the outer circumference of the cylindrical cap 27 of the separator filter 20 cooperate with notches 18 in the upper part of the bowl 10, thus ensuring good positioning and retention of the two elements. The cylindrical cap 27 of the separator filter forms an upper housing 29 in which a disc-shaped foam filter 30 is housed. The separator filter further comprises a filter grid 21 of substantially cylindrical shape of smaller diameter than the cap 27, which extends under this cap so as to extend into the central part of the cyclonic chamber 19 as has been done. described above. This filtering grid 21 comprises zones 22 with small openings on its circumference, in order to allow an air flow to pass while fulfilling a filtering function.

The separator filter 20 further comprises an element forming a ramp 23, which we will simply call a ramp, of helical shape, positioned under the cap 27 of the separator filter. This ramp 23 extends from an initial point 24 at the level of the lower surface of the cap 27, so that the final end of the ramp is located near the air inlet 13 of the bowl 10 when the cyclonic device is assembled. This ramp 23 then extends downward, traversing substantially half a turn, and occupying substantially the entire volume between the grid 21 and the side wall of the bowl 10, as can be seen in FIG. 6. The lower surface 25 of this ramp 23 therefore forms a helical guide surface for the incoming air flow, allowing it to initiate the downward swirling movement around the grid 21. The downward slope of this guide surface ensures that the air flow, after having made its first turn around the inner grille 21 in the cyclonic chamber 19, does not collide with the incoming air flow through the opening 13 of the bowl but continues its swirling path below. In addition, the guide surface 25 of the ramp 23 has a second inclination of the order of 10 to 15 degrees outwards, particularly visible in FIG. 8. It forms a slope in a direction going from the filter 21 towards the wall of the bowl 10, which favors the guiding of the air flow towards the wall of the bowl 10, thus increasing the centrifugal effect provided by the speed of rotation and preventing that the still polluted air does not pass through the openings of the zones 22 of the filtering grid 21 in this initial phase of treatment within the device.

Naturally, the invention is not limited to the geometry of the ramp 23 chosen in this embodiment. This ramp can in fact extend over at least a quarter of a turn and go up to the full turn, however preferably extending at least over a half-turn. In addition, its outward inclination is advantageous because it makes it possible to reduce the difference in diameter between the grid 21 and the bowl 10, that is to say the distance between the grid 21 and the wall of the bowl 10, while obtaining a satisfactory solution. An inclination of between 5 and 20 degrees is satisfactory, this angle being measured with respect to a plane perpendicular to the plane tangent to the grid 21 at the level of the guide surface 25. However, this inclination remains optional and not compulsory.

Fixing the ramp 23 directly on the separator filter 20 is advantageous since it makes it possible to obtain a high-performance final configuration of the cyclonic separation device by assembling a minimum of separate elements. This ramp can be obtained directly by molding and form a single piece with at least the cylindrical cap 27 of the separator filter 20 or as a variant be manufactured separately and then fixed by any means on the separator filter.

The different components of the separator filter could have other geometries without departing from the concept of the invention. Thus, the filtering grid 21 may not be cylindrical but may have a variable circular section, for example decreasing downwards as shown in the embodiment where it is thus more exactly a portion of a cone. This section could have another shape, for example elliptical or ovoid. The expression substantially cylindrical has been used to integrate these different variants. Likewise, the cap 27 could have any other rectangular, square, elliptical, etc. geometry.

FIG. 8 illustrates the separator filter 20 in section, and further illustrates the lower part of the filter according to this embodiment. The lower part of the cylindrical grid 21 forms a blind zone 26 delimited by a horizontal bottom of the grid 21, and by the lateral surfaces of the cylinder or cone ending in an inclined plane, of the order of 45 degrees, substantially parallel to lower bowl door 10. This geometry makes it possible to obtain a larger volume than that of the solutions of the state of the art in which the cylinder ends in a horizontal plane near the bottom of the grid, while having an attractive aesthetic appearance.

FIG. 9 illustrates the portion of the frame of the handle 4 of the vacuum cleaner forming a housing 35 for receiving the cyclonic separation device. This housing comprises a connection 36 in its lower part, at the end of a vertical suction pipe 40 coming from the nozzle 2. This connection is intended for a connection with the vertical pipe 11 integral with the bowl 10, in order to form a continuous and vertical suction pipe. On the other hand, this housing 35 comprises in its upper part a second connection 37 intended for the connection to the motor of the vertical air flow leaving the cyclonic separation device through the passage in the center of the cover 32. The bottom of the housing 35 comprises a vertical hollow part 38 to receive a part of the vertical pipe 11 of the cyclone separation device and a horizontal hollow part 39 to receive a part of the horizontal pipe 12 of the cyclone separation device and thus allow sufficient interlocking. of the cyclonic separation device within the handle 4 of the vacuum cleaner, so that its main body is in continuity with the rest of the handle 4, by at least partially masking the pipe portions 11, 12 to achieve an attractive aesthetic.

Such an architecture allows the bowl 10 to be guided during its repositioning in the apparatus.

By this solution, the assembly and disassembly of the cyclonic separation device 7 on the handle 4 of the vacuum cleaner is simple and user-friendly, which facilitates the emptying of the waste stored in the device.

Indeed, the mounting of the cyclonic separation device is done by positioning the lower end of the vertical pipe 11 in its connection 36 in the lower part of the housing 35, then by rotating the entire device towards the bottom of the housing. 35, while pressing down the cyclonic separation device to allow the downward retraction of a lower part of the pipe 11, by retracting a movable part held in the rest position by a spring, until the entire cyclonic separation device comes into abutment at the bottom of the housing 35. Releasing the downward pressure of the device allows the moving part to rise again under the effect of its return spring, at the same time driving upward the cyclonic separation device which finally comes to rest in the upper part of the housing 35, sufficient to guarantee a good top connection 32, 37 for the evacuation of the treated air flow, while ensuring an operational and efficient maintenance of the cyclonic separation device within the handle 4. Disassembly of the device is done in reverse, by first pressing it down before pivoting it forward.

The invention has been illustrated in the context of an implementation on a stick vacuum cleaner. However, the concept of the invention is compatible with any vacuum cleaner, whatever its power, even for high powers between 1500 and 1800 W, whatever the mode of operation of the vacuum cleaner, autonomously at the same time. using a battery or by connecting to the mains. In such cases, the dimensions of the device will be adapted to the flow conditions of the air streams. In addition, the cyclonic separation device could be used as the sole waste separator or in combination with a filter bag, such as in a canister vacuum cleaner, making it possible to reduce the amount of waste reaching the bag and therefore to reduce the inconvenience caused by it. maintenance operations for this solution.