HK1163471B - Centrifugal juicers - Google Patents

Description

Centrifugal juice extractor

The present invention relates to centrifugal juicers and in particular, although not exclusively, to juicers for domestic markets. Such juicers typically comprise a motor-driven appliance capable of extracting juice from a natural agricultural product, such as fruit (typically citrus fruit) and/or vegetables, and delivering the juice into a receptacle, such as a glass, jug or carafe, which is placed adjacent to the appliance body to receive the juice through an outlet tube.

Typically, such juicers employ a shredding (macerate) device, such as a disc cutter plate (chopper plate), which rotates at a relatively high speed to pulp the fruit or vegetable being juiced; the cutting plate includes, or is at least positioned near the bottom of, a frusto-conical filter member that is positioned within the generally cylindrical working space. The frustoconical side wall of the strainer member is pierced or otherwise formed with small holes and/or slots so as to have sufficient holes to allow the juice to pass through. The cutting plate and generally also the filter member are rotated sufficiently rapidly to separate the juice from the pulp residue, mainly comprising fibrous matter; the juice is collected and dispensed through the holes in the frustoconical wall, and the pulp residue is blocked by the filter member and is thrown generally upwardly and outwardly.

The working space is covered by a cover, the top of which passes a feed trough designed to feed the extracted produce, and a pusher is provided so that the produce can be pushed through the feed trough and into abrasive contact with the cutting plate (abrasive contact).

Appliances based on the above general configuration are also well established, can be manufactured economically and work well.

However, difficulties arise in several respects; in particular, the ease and ease with which the pulp residue can be collected and removed after completion of one or more juicing cycles depends on the capacity of the appliance. As mentioned before, pulp remains tend to be flung around inside and above the filter member and to adhere to the inner surface of the juicer, especially surfaces that deviate in any way from a smooth, linear form. Bearing in mind that in this respect, the pulp remains, when wet, are thrown against the inner juicer surface and therefore tend to adhere very strongly, and in practice it has been found that, at least partly due to the formation of eddies associated with the speed of rapid rotation employed, much of the pulp remains enter into the upper part of the working zone and adhere to the inner surface of the lid.

Many attempts have been made to make unwanted pulp residues adhere to the filter or caught instead of to the inner juicer surface, but no structure has been found to date which works effectively and in a user friendly way. It is therefore an object of the present invention to solve this problem.

DE-a-3610741 describes a juice extractor in which the rigid container used to collect pulp ejected from the extractor is replaced by a compressible container to increase the pulp throughput and thus reduce the frequency of removal/emptying.

According to the present invention there is provided a centrifugal juicer having a chopping device located in a working zone of the juicer, the working zone being covered by a lid and circumferentially defined by a substantially vertical wall; said cap having a circumferentially extending depending skirt surrounding, surrounded by, or abutting said generally vertical wall; the juicer further comprising means for rotating the chopping means about an axis of rotation to produce juice and pulp from the produce urged against the chopping means, filter means for separating the juice and pulp, means in communication with the juice outlet tube for collecting the juice and for storing the collected juice, and means for collecting the pulp; said means for collecting pulp communicating with said work area through a letterbox-like aperture in said depending skirt and/or in a generally vertical wall of said lid, and comprising a removable container formed with a filling aperture alignable with the letterbox-like aperture; the letterbox-like aperture and the filling aperture are arranged with respect to the work area to facilitate movement of pulp into the removable container.

In this way, pulp is forced through the letterbox-like aperture and the filling aperture, which are preferably closely juxtaposed and generally aligned when the container is mounted on the juicer, and thus a substantial amount of pulp is collected in the container.

Preferably, the container is mounted for sliding movement towards and away from the juicer for mounting and removal.

It is also preferred that a top plate extending from the lid of the juicer forms a hood of the container when it is mounted on the juicer, and that the filling aperture portion in the container is defined by an upper bridging member having a surface adapted to slide in contact or in close proximity to the underside of the top plate, thereby wiping accumulated pulp from the top plate when the container is slid away from the juicer for removal.

In some cases, it is preferred that the surface of the upper bridging member is shaped or otherwise configured to enhance the wiping action relative to the underside of the top plate.

In a preferred embodiment of the invention, the letterbox-like aperture is formed primarily in the depending skirt of the lid, and its lower edge is formed by an upwardly facing edge of the generally vertical wall.

It is also preferred that the top portion extending from the lid is formed with associated side members which extend at least to the depending skirt of the lid and support chute means which are configured to cooperate with complementary chute means carried by the container to accommodate said reciprocal sliding movement.

Still further preferably, the container is formed with a handle so that the container can be lifted up and also operated for the sliding movement; in addition, the handle is formed with a latch arrangement configured to engage with a complementary latch arrangement of the top panel to releasably lock the container to the juicer when the latch arrangement is fully engaged with the latch arrangement.

In a particularly preferred embodiment of the invention, the cover is made of a transparent or at least substantially transparent plastic material, so that the juicing process taking place in the working area can be observed. It is also preferred that the top plate is made of the same or similar plastic material, allowing the user to monitor the status of the container with respect to the pulp accumulation. The top plate may be integrally formed with the cover.

Further preferably, said letterbox-like aperture and said filling aperture are juxtaposed to define for said removable container a collecting aperture circumferentially offset with respect to the diameter of the working area aligned with said juice outlet duct; the biasing is such that a majority of the collection apertures are directed in a direction of rotation of the chopping device; forming a retaining wall for capturing the ejected pulp in the removable container and blocking recirculation of the pulp from the removable container into the work area.

In some preferred embodiments of the invention, the juicer further comprises a safety interlock device configured such that said means for rotating the shredding means is inoperative when the removable container is not operatively mounted to said juicer.

In some preferred embodiments the letter box-like outlet opening of the juice extractor's working area is provided with side walls and possibly also a bottom wall protruding through the filling hole into the removable container, thereby creating a chute that helps to guide pulp into the container.

Advantageously, the juicer may further comprise means to provide a tactile indication when the container is operatively mounted to the juicer body, and in a preferred embodiment such means may comprise first and second spring-loaded locking balls provided on the body of the juicer and positioned to snap into corresponding grooves formed in the bottom of the removable container.

Drawings

In order that the invention may be clearly understood and readily put into practical effect, an embodiment will now be described, by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 is a cross-sectional view of the essential components of a centrifugal juicer according to one example of the present invention;

figure 2 shows a perspective view of the juicer component shown in figure 1;

figure 3 shows a view from the rear of the juicer of figures 1 and 2 with parts broken away for clarity; and

figure 4 shows a plan view of a juicer with the lid and top extension removed to illustrate an alternative construction according to one particular example of the invention.

Detailed Description

Referring to the drawings, a centrifugal juicer is shown as part 10 and includes an open-topped, frusto-conical strainer bowl 12 rotatable about its vertical central axis 14 and formed with an apertured side wall 16 through which juice is intended to flow to a juice outlet duct 18 formed at or adjacent a bottom 20b of a generally cylindrical wall 20a, the generally cylindrical wall 20a defining a working area 20 of the juicer 10. In this particular example, the side wall 16 of the strainer bowl 12 forms a strainer arrangement for separating juice from unwanted debris of the juicing process, and it will be appreciated that the lower portion of the working zone constitutes a juice collection arrangement in communication with the juice outlet duct 18. In some cases, the filtering action of the wall 16 may be enhanced or supplemented by providing additional filters; some of these additional filters are disposable, others are washable and reusable.

A disk-shaped chopping plate 22 is typically introduced or mounted directly above the bottom of the frusto-conical filter bowl 12. In some embodiments, the bowl 12 and chopper plate 22 are integrally formed or attached to one another and rotate in the same direction and at the same speed. In alternative embodiments, the two components may rotate in the same direction at different speeds or in opposite directions. In some sophisticated applications, different combinations of the aforementioned rotating structures may be available, either automatically for use according to the function selection made by the user, or manually according to directly selectable user options.

A lid 26 of the appliance covers the working area 20 and is formed with a supply tube 28 through which agricultural products from which juice is extracted can be introduced into the appliance; a cover is removably mounted on the generally cylindrical wall 20a to define an upper portion of the working area 20 within which the frusto-conical filter bowl 12 and chopper plate 22 rotate. Pusher means 24 are also provided; the pusher is in the nature of a rod shaped and sized to pass through the supply tube and be used in a known manner, i.e., to push the produce against the chopping plate 22. Typically, pusher 24 is slidably mounted in supply tube 28; the external configuration of the pusher matches the shape of the inner surface of the supply tube. It will be appreciated that the supply tube 28 provides an aperture through the cap 26 that is closed by insertion of the pusher 24.

The plate 22 may include or be formed with any convenient structural design, such as upstanding vanes, ribs, teeth or other projections for chopping the produce being juiced.

To this end, as mentioned above, the juicer includes (among other things) a chopping device 22 and a filter bowl 12 located in the working area 20 of the juicer. The upper part of the working area 20 is covered by a cover 26 and is circumferentially defined by a substantially cylindrical vertical wall 20a provided outside the frusto-conical filter bowl 12; the bounding wall 20a is surrounded by, surrounds, or abuts the depending skirt 30 of the cap 26. A motor (not shown) is provided which is operated and controlled in a known manner to rotate the chopper apparatus 22 and strainer bowl 12 about its axis of rotation 14 to produce juice and pulp from the produce being urged by the aforementioned pushers 24. The foraminous wall 16 of the strainer bowl 12 acts to separate the juice from the pulp; the juice is collected and distributed as described previously. As mentioned previously, additional filter components may be provided to supplement the action of the wall 16 if desired. In this regard, for example, some juicers employ a disposable filter to line the interior of the wall 16 and thus improve the filtration efficiency, but the applicability of the invention is not affected by the particular filtration arrangement used.

The pulp, which is prevented by the wall 16 of the filter bowl 12 from advancing towards the outlet 18, tends to be flung upwardly and outwardly towards the upper part of the working zone and in particular towards the underside of the lid 26 and the upper part of the wall 20a and/or depending skirt 30 of the lid 26, depending on the particular arrangement used in that zone. According to the present example of the invention, as will now be described, a removable container for collecting pulp, such as a tank 32, is provided. The tank 32 communicates with the juice extractor working area via a letterbox-like aperture 34, in this example the aperture 34 is formed primarily through the depending skirt 30 of the lid 26, the lower edge of which is formed by the upwardly facing edge of the wall 20 a.

It will be appreciated that in other embodiments, depending on the precise configuration of the cap 26, the extent of the length of the depending skirt 30, and the connection between the skirt and wall, the aperture 34 may be formed to a greater extent within the wall 20a or even entirely within the wall 20 a.

The tank 32 is formed to be slidably removable from the juicer in a direction perpendicular to the axis of rotation 14 of the juicer and it is formed with a fill aperture 36 which aligns with the letterbox-like aperture 34. The apertures 34 and 36 are arranged so that pulp produced by the upwardly and outwardly thrown and rotated airflow as described above preferentially leaves the working area 20 of the juicer through them and is thrown into the sump 32. In this way, most of the pulp produced during the juicing process is effectively collected in the tank 32. In some practical embodiments of the invention, more than 90% of the pulp is consistently collected in the manner described above, leaving the inner surface of the juicer, and in particular leaving the lid 26 relatively free of unwanted pulp residue.

It is preferred (although not necessary at present) to provide a safety interlock to ensure that the motor of the centrifugal juicer 10 cannot operate when the bin 32 is not properly positioned and placed on the juicer body. In one embodiment, this interlock is provided by a reed switch mounted on the juicer body which controls the supply of current to the motor and does not open (i.e. blocks the supply of current) unless it detects the presence of a magnet carried by the reservoir 32. However, any suitable form and type of safety interlock may be used.

In a particularly advantageous construction, as shown in the figures, the top plate 38 extends outwardly from the lid 26 of the juicer and forms a hood for the tank 32 when the tank 32 is mounted on the juicer. In this example, the top plate 38 is integrally formed with the lid 26, but this is not required and the top plate may be formed separately from the lid 26 and attached to the lid 26, if preferred.

In any event, the bin 32 is mounted for sliding movement toward and away from the juicer for mounting thereto and removal therefrom. In this regard, as shown, it is preferred that the upper portion of the fill aperture 36 of the tank 32 is defined by an upper bridge member 40, the upper bridge member 40 being configured and adapted to slide in contact or in close proximity with the underside of the top plate 38 to automatically wipe accumulated pulp from the top plate when the container is slid away from the juicer for removal and emptying. If desired, the surface of the upper bridge member 40 facing the underside of the top plate 38 may be shaped or configured to enhance the wiping action. For example, the material of the bridging member may be thinned in the region of the facing surfaces to allow it to bend. In an alternative arrangement, the facing surface may be fitted with a flexible, resilient wiping member.

In some embodiments of the invention, bores 34 and 36 are generally the same size, and in this exemplary embodiment, bore 36 is slightly larger than bore 34 as measured from the circumference of working chamber 20. As such, the two holes are positioned to be closely juxtaposed and generally aligned when the tank 32 is assembled to the juicer 10. It will therefore be appreciated that the two apertures do not necessarily have to be of the same size, but that they together determine the overall size of the outlet aperture through which the pulp exits the working area 20 of the juicer and enters the hopper 32.

In the above described embodiments of the invention the letterbox-like aperture 34 is formed primarily in the depending skirt 30 of the lid 26, but if preferred the aperture 34 may extend into the outer wall 20a of the juicer body, or primarily or wholly therein, depending on the precise nature of the relationship between the wall 20a and the depending skirt 30 of the lid 26 which may (as mentioned previously) surround, be surrounded by or abut an upper portion of the wall 20 a.

In this exemplary embodiment, the top plate portion 38 extending from the lid 26 is formed with associated side members 42 and 44 which extend outwardly at least to the depending skirt 30 of the lid 26, and chute means such as 46 are provided for cooperation with complementary chute means such as 48 carried by the tank 42 to accommodate said reciprocating sliding movement. The depth and length dimensions of the side members 42 and 44 are sized to provide an adequate seal against material leakage, taking into general consideration the operating parameters of the present device; the dimensions shown in the drawings are not intended to limit any preferred configuration in this respect.

In a preferred embodiment, the outlet opening 34 from the working area 20 is provided with a side wall and possibly also a bottom wall, which protrudes through the filling hole 36 into the tank 32 and thus forms a chute (cut) for facilitating the entry of the pulp into the tank.

In some embodiments, it is preferable to provide a tactile cue when the bin 32 has been pushed fully into position against the body of the juicer 10, and thus properly installed for use. In one such embodiment, two spring-loaded ball traps are provided on the juicer body, positioned for snapping into corresponding grooves formed in the bottom of the tank 42. This configuration also helps to support and position the tank 42 in the correct position for use.

In this example, the container is formed with a handle 50 so that the tank can be lifted up and also operated to perform the sliding movement described above. A latch device (not shown) of any convenient type is provided for releasably locking the tank 32 to the juicer. The latching means preferably comprises a manually actuable lock introduced into the handle 50 having elements which engage with cooperating elements provided or formed in the underside of the top plate portion 38. In the locked condition, it will be appreciated that the two letterbox-like apertures 34 and 36 are at least substantially aligned and closely juxtaposed. It will be appreciated that the latch means should provide sufficient holding strength to resist the separating force caused by the ejected pulp.

Typically, the cover 26 is made of a transparent, or at least substantially transparent, plastic material so that the juicing process that takes place in the working area 20 can be observed. It is also preferred that the top plate 38 is made of the same or similar plastic material, allowing the user to monitor the status of the tank 32 with respect to the content of the accumulated pulp. As mentioned previously, the top plate may be integrally formed with the cover.

Depending on the dynamics of the flow of the pulp ejected into the tank 32, it may in some cases be useful to provide the top plate 38 with curved deflecting guide ribs (deflectors) that extend along the peripheral edge of the top plate 38 and serve to improve the sealing of the top plate with the tank. Such ribs are effective in guiding pulp away from the seal without adversely affecting the wiping action of the upper wall surface of the bridging member 40 along the underside of the roof 38.

It will be appreciated that the dimensions of the apertures 34 and 36 are influenced by various criteria specific to the individual juicer design, such as the size of the shredder plate, filter and working area or centrifuge. In one particular example, not intended to limit the scope of the claims of the present invention, for a working area between 160mm and 180mm in diameter and between 40mm and 50mm in height, typical dimensions for the holes 34 are between 100mm and 110mm in width and between 35mm and 55mm in height, and corresponding typical dimensions for the holes 36 are between 110mm and 120mm in width and between 50mm and 60mm in height.

In some embodiments of the invention, as shown in fig. 4, the collection apertures formed by the juxtaposition of apertures 34 and 36 are circumferentially offset, with the greater part of the open area of the collection apertures facing in the direction of rotation of the frusto-conical filter bowl 12. This configuration forms a retaining wall 52, the retaining wall 52 being formed by the edge of the wall 20a, the skirt 30 of the lid 20 and the sump 32, trapping the ejected pulp in the sump 32 and helping to inhibit recirculation of the pulp into the work zone 20.

As shown in fig. 4, the letterbox-like aperture 34 and the filling aperture 36 are juxtaposed so as to define a collecting aperture for the removable container 32, which is circumferentially offset with respect to the diameter of the working area aligned with the juice outlet duct 18 (and, in this case, the handle 50 of the container 32); this offset is such that if the size of the collecting aperture is measured in the direction of rotation (i.e. in the circumferential direction of the wall 20a defining the working area) as a whole as (a + b), then a large part of the relevant collecting aperture size faces the direction of rotation of the chopping device; thus forming a retaining wall 52 on the downstream side of rotation for capturing the ejected pulp in the removable container and inhibiting recirculation of pulp from the removable container into the work area.

With the invention described herein, large quantities of unwanted pulp residue are conveniently and cleanly collected and held in the bin 32 for disposal.

Claims (15)

1. A centrifugal juicer (10) having a chopping device (22) located in a working zone (20) of the juicer, the working zone (20) being covered by a lid (26) and circumferentially defined by a generally vertical wall (20 a); the cap having a circumferentially extending depending skirt (30) surrounding the substantially vertical wall (20 a), surrounded by the substantially vertical wall (20 a), or abutting the substantially vertical wall (20 a); the juicer further comprising means for rotating the chopping means about an axis of rotation (14) to produce juice and pulp from the agricultural product urged against the chopping means (22), filter means (12) for separating the juice and pulp, means in communication with the juice outlet duct (18) for collecting the juice and for storing the collected juice, and means for collecting the pulp; -said means for collecting pulp communicates with said work area (20) through a letterbox-like aperture (34) in said depending skirt (30) and/or said substantially vertical wall (20 a) of said lid, characterized in that it further comprises a removable container (32) formed with a filling aperture (36) alignable with the letterbox-like aperture (34); the letterbox-like aperture and the filling aperture being arranged with respect to the work area (20) to facilitate movement of pulp to the removable container (32); wherein the container is mounted for sliding movement towards and away from the juicer (10) for mounting and removal; the juicer also has a roof (38) extending from the lid (26) of the juicer and forming a hood for the container (32) when mounted to the juicer; wherein the filling aperture (36) in the container (32) is partially defined by an upper bridging member (40), the upper bridging member (40) having a surface adapted to slide in contact or in close proximity to the underside of the top plate (38) so as to wipe accumulated pulp from the top plate when the container (32) is slid away from the juicer (10) for removal.

2. A juicer according to claim 1, wherein the letterbox-like aperture (34) is formed wholly in the depending skirt (30) of the lid (26).

3. A juicer according to claim 1, wherein the letterbox-like aperture (34) is formed primarily in the depending skirt (30) of the lid (26) and its lower edge is formed by an upwardly facing edge of the substantially vertical wall (20 a).

4. A juicer according to any preceding claim, wherein the roof (38) extending from the lid (26) is formed with associated side members (42; 44) that extend at least to the depending skirt (30) of the lid and support chute means configured to cooperate with complementary chute means carried by the container (32) to accommodate said sliding movement.

5. A juicer according to any one of claims 1 to 3, wherein the container (32) is formed with a handle (50) so that it can be lifted and also operated for said sliding movement.

6. A juicer according to claim 5, wherein the handle (50) is formed with latch means configured and adapted to engage with complementary latch means provided on the top panel (38) to releasably latch a container (32) to the juicer (10) when the latch means is fully engaged with the complementary latch means.

7. A juicer according to any one of claims 1 to 3, wherein the lid (26) is made of a transparent or at least substantially transparent plastics material, so that the juicing process taking place within the working zone (20) can be observed.

8. A juicer according to claim 7, wherein the roof (38) is made of the same or similar plastics material as the lid (26), allowing a user to monitor the condition of the container (32) with respect to the accumulation of pulp.

9. A juicer according to any one of claims 1 to 3, wherein the roof (38) is integrally formed with the lid (26).

10. A juicer according to any one of claims 1 to 3, wherein the letterbox-like aperture (34) and the filling aperture (36) are juxtaposed to define for the removable container (32) a collection aperture circumferentially offset with respect to the diameter of the working area (20) aligned with the juice outlet duct (18); the biasing is such that a majority of the collection apertures are directed in a direction of rotation of the chopping device (22); thereby forming a retaining wall for capturing the ejected pulp in the removable container (32) and blocking recirculation of the pulp from the removable container into the work area (20).

11. A juicer according to any one of claims 1 to 3, further comprising a safety interlock device configured such that said means for rotating the shredding means is inoperative when the removable container (32) is not operatively mounted to the juicer (10).

12. A juicer according to any one of claims 1 to 3, wherein the surface of the upper bridging member (40) is shaped or configured to enhance the wiping action against the underside of the top plate (38).

13. A juicer according to any one of claims 1 to 3, wherein the letterbox-like aperture (34) of the working area (20) of the juicer (10) is provided with side walls and a bottom wall projecting through the filling aperture (36) into the removable container (32) forming a chute to assist in directing pulp into the container (32).

14. A juicer according to any one of claims 1 to 3, further comprising means to provide a tactile indication when the container (32) is operatively mounted to the body of the juicer (10).

15. A juicer according to claim 14, wherein the means to provide a tactile indication comprises first and second spring-loaded locking balls provided on the body of the juicer (10) and positioned to snap into corresponding grooves formed in the base of the removable container (32).