[0001] The present invention relates to a retaining device for retaining a magnetisable
object which has been thrown into a refuse receptacle.
[0002] One of the problems encountered in the hotel, restaurant and catering trade, as well
as in canteens, is that when food remains are thrown away, the cutlery is inadvertently
also thrown away. This problem occurs in particular in the hotel, restaurant and catering
trade and in canteens where meal trays are used, which are emptied over a waste bin.
However, the problem also occurs with plates containing food remains, which are emptied
over a dustbin.
[0003] In this context, it is known to position magnets at the inlet passage of a refuse
receptacle which then retain magnetisable objects which are inadvertently thrown away.
Thus, it is possible to retain cutlery and other objects which contain a magnetisable
material. The cutlery or other object is attracted by the magnet and can subsequently
be removed again without having ended up in the refuse receptacle itself.
[0004] Examples of such systems can be found, inter alia, in
US 4,782,970,
WO 03/018441,
US 6,129,213,
US 4,494,657 and
US 4,706,818. All these systems comprise a lid design with an inlet chute or inlet funnel which
leads to an inlet passage. The inlet passage in turn ends in the interior of the refuse
receptacle. The material to be thrown away, such as food remains, is deposited in
the inlet chute or inlet funnel and guided to the inlet passage by the inlet chute/inlet
funnel.
[0005] In the case of publication
US 4,782,970, a rectangular inlet duct defining the inlet passage is provided, as are magnets
which are positioned along opposite side walls of said duct.
[0006] In the case of publications
WO 03/018441 and
US 6,129,213, magnets are provided along the bottom of the immovably fixed inlet chute leading
to the inlet passage.
[0007] In the case of publications
US 4,706,818 and
US 4,494,657, magnets are provided which extend substantially horizontally through the passage
area of the inlet opening. A funnel is arranged around the inlet opening in order
to guide the material to the inlet opening.
[0008] In
US 4,706,818, two tubular magnet elements are provided, which are immovable and extend in the
horizontal direction through a round inlet duct.
[0009] In
US 4,494,657, an elongate horizontally extending magnetic retaining element is provided in the
inlet passage below the disposal aperture. The magnetic retaining element in this
case comprises a shaft made of a non-magnetic material, on which spaced-apart pairs
of metal plates in the shape of an equilateral triangle are provided. Between each
pair of metal plates in each case one magnet is provided. The central shaft in this
case runs through the centre of the metal plates. The triangular metal plates can
be rotated about the longitudinal axis of the shaft. The triangular plates are magnetic
on account of the magnets between each pair of plates.
[0010] The systems comprising an inlet chute have the drawback that they require the modification
of the entire lid of the refuse receptacle, which makes this retaining device unsuitable
for use with refuse receptacles if it is envisaged to use the associated original
lid. Providing magnets in the bottom of the inlet chute furthermore has the drawback
that when a magnetisable object has been retained by the magnet, said retained object
forms an obstacle for the expedient discharge of further waste via the inlet chute
to the inlet passage. In this case, it is even conceivable that the further waste
nevertheless pushes the initially retained magnetic object further down the discharge
chute through the discharge passage. The magnetic object to be retained will then
still have ended up in the refuse receptacle.
[0011] Refuse receptacles which are provided with magnets in the walls of the inlet duct,
as is the case with
US 4,782,970, and refuse receptacles in which magnet elements extend horizontally between the
walls of the inlet duct basically have the same drawback. Magnetic objects retained
by the magnets form impediments for further waste to pass through and may, in addition,
also be pushed down further by the further waste and still end up in the refuse receptacle.
[0012] In the case of the system according to
US 4,494,657, the elongate retaining element is arranged in such a manner - see column 6, lines
49-52 - that the entire stream of material is forced to engage with the magnetic retaining
element. This means that all objects made of magnetic material would be retained,
as indeed intended. However, this design has a number of serious drawbacks. Firstly,
elongate objects, such as cutlery, the longitudinal axis of which is at right angles
to the pivot pin, can be caught by the triangular plates magnetised by the magnets.
In this situation, some rotation about the shaft of the retaining element may take
place, but the inlet opening will essentially immediately become blocked. In case
an elongate object, such as a piece of cutlery, the longitudinal direction of which
is substantially parallel to the axis of the retaining element, is retained against
the side edges of the triangular plates - which is not likely in practice since the
magnetic force will be too small there - then the retaining element will rotate on
account of the weight of the retained object so that the retained object will be suspended
from it, as it were. However, waste which follows directly behind the retained objects
will easily knock this suspended object off, so that it still ends up in the refuse
receptacle. Furthermore, it is the case that, when cutlery is thrown in the refuse
receptacle inadvertently, this will usually be not just a single piece of cutlery,
but generally two or more pieces of cutlery. As soon as the first piece of cutlery
is retained and hangs from the retaining element, any further piece of cutlery which
is retained in a corresponding manner will result in the triangular plates which still
have an empty side becoming oriented in the horizontal direction. Thus, the flow of
material through the inlet opening is blocked. In order to remove the retained cutlery
- should it not have been knocked off - from the retaining element, the waste which
is situated on top of the retaining element has to be removed first, which is usually
quite cumbersome. The retaining device disclosed in
US 4,494,657 is therefore not reliable and if the object is retained at all, it is in this case
cumbersome to effectively remove the object from the retaining element. There is a
high risk that the initially retained object is knocked off during the removal of
the other waste and ends up in the refuse receptacle.
[0013] It is an object of the present invention to provide an improved retaining device
for retaining a magnetisable object thrown into a collecting receptacle, which retaining
device according to the invention eliminates the drawbacks of the prior art retaining
devices.
[0014] According to the invention, this object is achieved by providing a retaining device
for retaining a magnetisable object which has been thrown into a refuse receptacle,
such as a waste bin, comprising:
a retaining body;
a pivot pin;
in which the retaining body is in the shape of a saddle roof;
in which each roof surface of the saddle roof, viewed in the direction of inclination
(A) of the respective roof surface, extends between the ridge of the saddle roof and
a longitudinal edge turned away from the ridge;
in which the retaining body is mounted on the pivot pin at the ridge of the saddle
roof so as to be able to pivot to and fro about the pivot pin;
in which the retaining body is provided at and along each longitudinal edge with a
magnet element in order to detain, by means of magnetic attraction, said magnetisable
object which moves along the respective roof surface in the direction of inclination
(A).
[0015] The retaining body in the shape of a saddle roof in this case acts as a kind of guide
surface along which the waste, which may contain a magnetisable object, is guided
into the refuse receptacle. Under the effect of the weight of the waste, the saddle
roof which is able, as it were, to pivot along the ridge, will be able to tilt in
order to facilitate the flow of waste to the interior of the refuse receptacle. Now
if there is a magnetisable object, such as a piece of cutlery, in the waste, then
this will likewise be guided along a roof surface of the saddle roof. As each roof
surface is provided with a magnet element at and along the longitudinal edges turned
away from the ridge - in the case of a real roof, as it were the edges where the gutter
is provided - the retained magnetisable object is retained at the bottom edge of the
roof surface and the saddle roof thus tends to tilt further on account of the weight
and thus assists the further flow of waste by increasing the passage therefor.
[0016] In order to increase the retaining force of the magnet element, it is advantageous
according to the invention if each magnet element is composed of a row of magnets,
in which each magnet has a N-Z centre axis which extends parallel to the longitudinal
edge, and in which the corresponding poles of adjacent magnets in the row are in each
case turned towards one another. In this context, the term N-Z centre axis is understood
to mean the north/south centre axis, which extends from the north pole to the south
pole of the magnet. Turning the corresponding poles of adjacent magnets in the row
of magnets towards one another - that is to say the north pole of one magnet will
be turned towards the north pole of the adjacent other magnet or the south pole of
one magnet will be turned towards the south pole of the adjacent other magnet - achieves
the effect that the magnetic field strength along the row remains strong along the
entire length of the row. If the magnets were placed in a row with the north poles
facing the south poles, then the magnetic field lines would run from the ends of the
row in an arc along the row towards one another, with the concentration of the field
lines - and thus the magnetic field strength - in the centre of the row being relatively
small, resulting in a relatively low retaining force in the centre of the row.
[0017] According to the invention, it is furthermore advantageous if, on the side of each
row of magnets which is turned away from the roof surface, a strip of ferromagnetic
material is provided, so that the magnetic field force is greater on the side of the
row which faces the roof surface than on the side of the row which is turned away
from the roof surface. As a result thereof, the magnetic attraction is greatest on
the top side of the roof surface. This prevents that a magnetisable object, which
partly projects beyond the bottom edge (gutter edge) of the roof surface, can topple
over the bottom edge of the roof surface on account of magnetic forces prevailing
on the underside of the roof surface. This could, for example, be caused by further
waste which is deposited in the refuse receptacle. This also reduces the risk of a
retained magnetisable object becoming stuck exactly along the bottom edge/gutter edge
of the roof surface where it is relatively susceptible to being pushed off the roof
surface by further waste deposited in the refuse receptacle.
[0018] In this case, it is furthermore advantageous if the magnetic field force is at least
twice as large on the side of the row which faces the roof surface as on the side
of the row which is turned away from the roof surface.
[0019] In order to make it possible to retain magnetisable objects along the entire roof
surface, it is advantageous according to the invention if the magnet element extends
along substantially the entire longitudinal edge.
[0020] In order to make it possible to install the retaining device in a refuse receptacle
easily and to readily remove it therefrom for the purpose of, for example, cleaning,
it is advantageous according to the invention if the pivot pin, at its free ends,
has supports in order to be supported on an edge, such as the top edge of the wall
of a refuse receptacle. Thus, the retaining device according to the invention can
easily be placed inside the top of a refuse receptacle by placing it on the top edge
of the wall of a refuse receptacle by means of the supports. If desired, the usual
lid construction associated with the respective refuse receptacle can simply be placed
on the refuse receptacle when the retaining device according to the invention is suspended
therein. In this case, it is advantageous according to the invention if the supports
have an L-shaped or U-shaped cross section. In the case of an L-shaped cross section,
one leg of the L will point downwards in the vertical direction and the other leg
of the L will be in line with the shaft, in the horizontal direction. A support of
this type can be supported on many kinds of edges. If desired, the support can also
be of a U-shaped design. However, in that case, the legs of the U-shape have to be
sufficiently wide apart in order to accommodate the edge therebetween on which the
retaining device is supported. In addition, the L-shaped or U-shaped supports make
it easy to displace the retaining device along the edge on which it is supported,
in a direction transverse to the longitudinal direction of the pivot pin. Thus, the
position of the retaining device can be adjusted.
[0021] With the retaining device according to the invention, it is furthermore advantageous
if the pivot pin is of a telescopic design so that the length thereof is adjustable.
This makes it possible to match the length of the pivot pin to the width of the inlet
passage of the refuse receptacle in which the retaining device is to be fitted. Such
a telescopic pivot pin can be designed in many different ways. In this case, it is
advantageous according to the invention if the pivot pin comprises a central tube
part with a shaft part at both ends, which shaft parts are displaceable in the tube
part. Thus, the pivot pin can be adjusted at both ends and the position of the retaining
device in the inlet passage of the refuse receptacle can be more readily adjusted.
[0022] According to the invention, it is furthermore advantageous if the retaining body
is displaceable along the pivot pin. Thus, the position of the retaining body with
respect to the inlet passage of the refuse receptacle can be adjusted in the longitudinal
direction of the pivot pin.
[0023] With the invention, it is advantageous if the roof surfaces between them enclose
an angle which, on the one hand, is 90° or greater, preferably 120° or greater, and,
on the other hand, is 160° or smaller, preferably 150° or smaller. The angle enclosed
by the roof surfaces is thus in the range of 90-160° or 90-150° or 120-160° or 120-150°.
The angle enclosed by the roof surfaces may be, for example, approximately 135°. On
the one hand, it is important that the roof surfaces are not excessively steep, as
the waste otherwise passes through much too easily, even at a neutral position. This
determines the lower threshold of at least 90°. In practice, it was found that 90°
(at which each roof surface is at an angle of 45° with respect to the vertical) is
at a relatively steep angle, but still works well. Preferably, the lower threshold
of the angle enclosed by the roof surfaces is therefore 120°, that is to say, in the
starting position, each roof surface is at an angle of 30° with respect to the horizontal.
On the other hand, it is important in this case that there is an already sufficiently
steep initial incline in the starting position since the waste would otherwise not
have a tendency to slide along the roof surface and could remain stuck (if the saddle
roof remains balanced). This results in a maximum angle of approximately 160° enclosed
by the roof surfaces, which is preferably at most 150°.
[0024] In order to concentrate the magnetic effect as much as possible around the magnet
elements, it is advantageous according to the invention if the roof surfaces are made
of a non-magnetisable material.
[0025] In order to further improve the magnetic action of the retaining device according
to the invention, it is advantageous according to the invention if the retaining device
is substantially - that is to say except for the magnet elements and the optional
ferromagnetic strip underneath - made from a non-magnetisable material.
[0026] According to a further aspect, the invention relates to a refuse receptacle, such
as a waste bin, having an inlet passage, in which a retaining device according to
the invention is provided in the inlet passage.
[0027] The present invention will be explained below with reference to an exemplary embodiment
which is illustrated diagrammatically in the drawing, in which:
Fig. 1 shows a diagrammatic, perspective view of a refuse receptacle according to
the invention;
Fig. 2 shows a diagrammatic, perspective view of the disposal passage of the refuse
receptacle from Fig. 1, but with the lid removed; and
Fig. 3, in the direction indicated by arrow III from Fig. 2, a diagrammatic top view
of a retaining device according to the invention;
Fig. 4 shows a diagrammatic, perspective view of the retaining device according to
Fig. 3.
[0028] Figs. 1 and 2 show a refuse receptacle 1 in the shape of a waste bin provided with
a bin liner 5. As illustrated in Fig. 1, the refuse receptacle 1 is provided with
a lid construction having a lid frame 2, to which a lid 3 is hingedly attached. The
lid frame 2 rests on the top edge 9 of the refuse receptacle. In the inlet passage,
in this case a disposal passage 11, of the refuse receptacle 1, a retaining device
4 according to the invention is provided. This retaining device 4 is provided with
supports 10 having an L-shaped cross section. With a vertical limb of the L-shape,
these supports rest against the inside of the wall of the refuse receptacle 1 and
with a horizontal limb of the L-shape, these supports 10 rest on the top edge 9 of
the refuse receptacle 1.
[0029] As Fig. 1 furthermore shows, it is possible, once the lid 3 has been opened, to throw
food remains 8 from a plate 6 into the refuse receptacle 1 via the disposal passage
11. If there are still pieces of cutlery 7 between the food remains 8, they will also
be thrown from the plate 6 through the disposal passage 11. These pieces of cutlery
7 are retained by the magnet elements of the retaining device 4 which are still to
be described. If these pieces of cutlery 7 were not retained, they would end up in
the interior of the refuse receptacle 1, together with the remainder of the waste
and be disposed of together with the rest of the waste, resulting in an economic loss.
[0030] The retaining device according to the invention will now be described in more detail
with reference to Figs. 3 and 4. The retaining device 4 according to the invention
is substantially composed of a retaining body 12 and a pivot pin 13. The retaining
body 12 is preferably substantially made of stainless steel and/or galvanised steel,
at least all external surfaces of the retaining body will preferably be made of stainless
steel and/or galvanised steel. The reason for this is that stainless steel and galvanised
steel can be cleaned in a simple and hygienic way, even after prolonged use, which
is desirable for applications in the hotel, restaurant and catering trade and canteens.
In addition, many grades of stainless steel, in particular the good grades, are not
magnetic. As can readily be seen in particular in Fig. 4, but also in Figs. 1 and
2, the retaining body 12 has the shape of a saddle roof. The saddle roof has two roof
surfaces 14 and 15 which enclose an angle α. Each of the roof surfaces 14 and 15,
in the neutral position of the retaining body 12, extends at the same angle β with
respect to the horizontal 16. The relation between the angles α and β is defined as
180° = α + 2β. In this exemplary embodiment, the angle β is approximately 22°.
[0031] Each roof surface 14, 15 extends in a direction of inclination A of the respective
roof surface 14, 15 between the ridge 17 of the saddle roof 12 and a longitudinal
edge 18 turned away from the ridge 17. In the case of a real roof on a building, the
longitudinal edge 18 would be the edge where the gutter is provided and is therefore
also referred to as the gutter edge of the saddle roof 12.
[0032] The retaining body 12 in the shape of a saddle roof is substantially composed of
a hollow box with stainless-steel walls.
[0033] The pivot pin 13 has a pivot axis 19 which extends along the ridge 17 of the saddle
roof. A magnet element 20 is provided along the longitudinal edges/gutter edges 18
of each roof surface 14, 15. This magnet element is provided inside the retaining
body, so that the magnet element 20 is protected from waste which passes along the
retaining body. Each magnet element 20 is in this case composed of a row of magnets
21, 22 and 23. As is indicated in Figs. 3 and 4 by means of the letters N and Z, the
corresponding poles of the magnets which are adjacent to one another in the row are
in this case turned towards one another. The south pole of magnet 21 is thus turned
towards the south pole of magnet 22. The north pole of magnet 22 is turned towards
the north pole of magnet 23. Thus, the concentration of the magnetic field strength
lines along the row 20 is increased in the longitudinal direction of the row of magnets
20. In order to make the magnetic field strength of rows 20 of magnets 21, 22, 23
on the underside of said rows 20 (the side of the row turned away from the roof surface
14, 15) smaller than the magnetic field strength on the top side of the rows 20 of
magnets 21, 22, 23 (the side of the row turned towards the roof surface 14, 15), the
rows 20 of magnets 21, 22, 23 are arranged on a strip 24 of ferromagnetic material,
in particular steel plate having a thickness of approximately 8 mm.
[0034] In the embodiment illustrated in Figs. 3 and 4, the pivot pin 13 is designed as a
central tube part 25 with a shaft part 26 at both ends which can be displaced therein.
Thus, as is indicated by means of double arrows in Fig. 3, the distance between the
supports 10 and the retaining body 12 can be adjusted. As a result, the position of
the supports can be adjusted depending on the width of the disposal passage 11 of
the refuse receptacle 1. The central tube part 25 may be one long tube part which
extends from one side of the retaining body 12 to the other side, but may also comprise
two separate tube elements. As has been indicated in Fig. 2 by means of the double
arrow, the supports 10 can also be displaced in a direction transverse to the pivot
pin along the top edge 9 of the refuse receptacle 1.
[0035] It will be clear that various variants and modifications can be made to the refuse
receptacle and retaining device illustrated in Figs. 1-4 without departing from the
scope of the invention defined in the subclaims. Thus, for example, it is not necessary
for the refuse receptacle to have a lid construction 2, 3. Furthermore, the retaining
body may be of a different design.
1. Retaining device (4) for retaining a magnetisable object (7) which has been thrown
into a refuse receptacle (1), such as a waste bin, comprising:
a retaining body (12);
a pivot pin (13);
in which the retaining body (12) is in the shape of a saddle roof;
in which each roof surface (14, 15) of the saddle roof, viewed in the direction of
inclination (A) of the respective roof surface (14, 15), extends between the ridge
(17) of the saddle roof and a longitudinal edge (18) turned away from the ridge (17);
in which the retaining body (12) is mounted on the pivot pin (13) at the ridge (17)
of the saddle roof so as to be able to pivot to and fro about the pivot pin (13);
in which the retaining body (12) is provided at and along each longitudinal edge (18)
with a magnet element (20) in order to detain, by means of magnetic attraction, said
magnetisable object (7) which moves along the respective roof surface (14, 15) in
the direction of inclination (A).
2. Retaining device (4) according to Claim 1, in which each magnet element (20) is composed
of a row of magnets (21, 22, 23); in which each magnet has a N-Z centre axis which
extends parallel to said longitudinal edge (18); in which the corresponding poles
of adjacent magnets in the row are in each case turned towards one another.
3. Retaining device (4) according to Claim 2, in which, on the side of each row of magnets
(21, 22, 23) which side is turned away from the roof surface (14, 15), a strip (24)
of ferromagnetic material is provided, so that the magnetic field force is greater
on the side of the row (20) which faces the roof surface (14, 15) than on the side
of the row (20) which is turned away from the roof surface (14, 15).
4. Retaining device (4) according to Claim 3, in which the magnetic field force, on the
side of the row (20) turned towards the roof surface (14, 15), is at least twice as
large as on the side of the row (20) which is turned away from the roof surface (14,
15).
5. Retaining device (4) according to one of the preceding claims, in which the magnet
element (20) extends along substantially the entire longitudinal edge (18).
6. Retaining device (4) according to one of the preceding claims, in which the pivot
pin (13), at its free ends, has supports (10) in order to be supported on an edge
(9), such as the top edge of the wall of a refuse receptacle (1).
7. Retaining device (4) according to Claim 6, in which said supports (10) have an L-shaped
or U-shaped cross section.
8. Retaining device (4) according to one of the preceding claims, in which the pivot
pin (13) is of a telescopic design so that the length thereof is adjustable.
9. Retaining device (4) according to Claim 8, in which the pivot pin (13) comprises a
central tube part (25) with a shaft part (26) at both ends which shaft parts are displaceable
in the tube part.
10. Retaining device (4) according to one of the preceding claims, in which the retaining
body (12) is displaceable along the pivot pin (13).
11. Retaining device (4) according to one of the preceding claims, in which the roof surfaces
(14, 15) between them enclose an angle which, on the one hand, is 90° or greater,
preferably 120° or greater, and, on the other hand, is 160° or smaller, preferably
150° or smaller.
12. Retaining device (4) according to one of the preceding claims, in which the roof surfaces
(14, 15) are made of a non-magnetisable material.
13. Retaining device (4) according to one of the preceding claims, in which the retaining
device (4) is substantially made of a non-magnetisable material.
14. Refuse receptacle (1), such as a waste bin, having an inlet passage (11), in which
a retaining device (4) according to one of the preceding claims is provided in the
inlet passage (11).