BACKGROUND OF THE INVENTION
[0001] The present invention relates to a machine for making ice cubes, including a safety
device against the overload of the water tray or basin tilting mechanism.
[0002] As is known, there are already available on the market machines for making ice cubes,
of the so-called blade type, which comprise a tray or water basin into which, through
a level control float element, there is supplied water; in the water tray there are
engaged the end portions or lugs of an evaporator, which lugs cause ice cubes to be
formed around said lugs, and said formed ice cubes being detached, by reversing the
thermal cycle, and specifically by introducing a hot fluid into the evaporator.
[0003] The formed ice cubes, in particular, are ejected by downward tilting the tray, owing
to the provision of a grid allowing the ice cubes to be outwardly ejected.
[0004] The tray, in particular, is tilted by a cam, controlled by a connecting rod, which
cyclically causes the tray to turn during a lowering step and, then, in a raising
step in order to recover it to the starting conditions thereof.
[0005] In such an operation, it frequently occurs that one or more ice cubes can not be
outward ejected, so that said ice cubes will be arranged or jammed between the grid
and evaporator, and because of this the operator can be damaged under the stress caused
by the jammed ice cubes, or can be damaged the coupling mechanical parts or the driving
geared motor unit.
SUMMARY OF THE INVENTION
[0006] Accordingly, the aim of the present invention is to overcome the above mentioned
drawbacks, by providing an ice cube making machine, including a safety device adapted
to protect the machine against a possible overload of the tray tilting mechanism thereof.
[0007] Within the scope of the above mentioned aim, a main object of the present invention
is to provide such a safety device which is also specifically designed for protecting
both the mechanical parts of the machine and the geared motor unit thereof from possible
overloads.
[0008] Yet another object of the present invention is to provide such an ice cube making
machine which is adapted to automatically remove any damaging obstacles during the
operation thereof.
[0009] Yet another object of the present invention is to provide such an ice cube making
machine which is very reliable and safe in operation, can be easily made starting
from easily available elements and materials and which, moreover, is very competitive
from a mere economic standpoint.
[0010] According to one aspect of the present invention, the above mentioned aim and objects,
as well as yet other objects, which will become more apparent hereinafter, are achieved
by an ice cube making machine including a safety device for protecting against overloads
a tilting mechanism of a water tray thereof, said water tray being pivoted to a machine
bearing framework and coupled, through a rod, to a cam, driven by a geared motor unit,
for cyclically tilting said water tray, characterized in that said machine further
comprises clutch means, arranged between said cam and geared motor unit, for preventing
obstacles for damaging said machine during the tilting operation of said water tray.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Further characteristics and advantages of the invention will become more apparent
hereinafter from the following detailed disclosure of a preferred, though not exclusive,
embodiment of an ice cube making machine, including a safety device, against the overload
of the tray tilting mechanism, which is illustrated, by way of an indicative, but
not limitative, example in the accompanying drawings, where:
Figure 1 is a schematic perspective view of the subject machine for making ice cubes;
Figure 2 is a side elevation view illustrating the coupling of the rod to the water
tray and to the cam in turn coupled to the geared motor unit;
Figure 3 illustrates a first embodiment of the clutch or friction means;
Figure 4 is a cross-sectional view illustrating a further embodiment of the clutch
or friction means;
Figure 5 illustrates yet another embodiment of resilient means associated with the
clutch means; and
Figure 6 schematically illustrates the operation of the cam provided for tilting the
water tray.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] With reference to the number references of the above mentioned drawing figures, the
ice cube making machine 1, including a safety device for protecting the machine elements
against possible overloads of the water tray tilting mechanism, comprises a bearing
framework 2, to which there is pivoted or articulated, at one end portion thereof,
a water tray 3 provided for receiving ice forming water, being supplied to a set level,
through a water controlling float.
[0013] On the bottom of the water tray'there is provided a grid 6, also pivoted on the same
pivoting axis as the water tray; moreover there is provided an evaporator 7, including
lugs 8, immersed in the water tray.
[0014] The machine further comprises a bladed shaft 9, associated with a geared motor unit
therefor, in order to stir the ice forming water and detect the size of the ice cubes
being formed, so as to stop an ice cube making cycle and start another ice cube making
cycle.
[0015] The water tray can be tilted, owing to the provision of a rod 11, which is pivoted
to a middle point of said tray and, at the other end thereof, to the periphery of
a circular cam 13, provided with a notch 14, thereon a microswitch 15 operates, in
order to control or drive a geared motor unit 16 for operating the cam.
[0016] The main feature of the invention is that the cam 13 is connected to the shaft 17
projecting from the geared motor unit 16 through the interposition of clutch means.
[0017] Said clutch or friction means, as is clearly shown in Figure 3, are provided with
a conic end piece 20, keyed on the shaft 17, which engages in a conic seat or recess
21, provided on the hub 22 of the cam 13.
[0018] The friction contact is performed owing to the provision of one or more cup springs
24, arranged on the shaft 17 and held in a pressed condition by a nut 25, coupled
to the threaded end portion 26 of the shaft 17; the cup springs, in particular, affect
a washer 27, which axially presses on the hub 22, including the mentioned conic recess.
[0019] In the case of an obstacle, which will be conventionally constituted by one or more
ice cubes interposed between the grid and lugs, the conic end piece 20 and conic recess
21 will mutually slide, thereby affording a free operation of the geared motor unit,
without damaging this latter or other mechanical elements.
[0020] As shown in Figure 4, the clutch or friction means can comprise a cylindric end piece
30, including a flange 31 and keyed on the shaft 17.
[0021] In this case, there is moreover provided a hub 22 including a cylindric recess 33,
which is still axially pressed by a washer 27 urged by cup springs 24.
[0022] If desired, as clearly shown in Figure 5, the mentioned resilient means, instead
of being formed by one or more cup springs, can comprise a coil spring 40 or any suitable
resilient means.
[0023] Figure 6 is a detail view illustrating the operation cycle of the cam, and clearly
shows the locating of the coupling rod which, during the cyclical rotation of the
cam, will cause the water tray to be lowered and then raised again.
[0024] In the case of jammed ice cubes, the operation of the motor can continue without
the rotation of the cam.
[0025] During this step, the ice cube, being in contact with the evaporator therethrough
a hot fluid is caused to pass, will be dissolved, thereby the obstacle will be automatically
removed without causing any damages.
[0026] From the above disclosure it should be apparent that the invention fully achieves
the intended aim and objects.
[0027] In particular, the fact is to be pointed out that there are used clutch or friction
means which have been specifically designed for disengaging the geared motor unit
and water tray, by providing two sliding surfaces which are precisely made of materials
adapted to allow a continuous type of sliding, for a time which is sufficient to provide
a perfect operation of the machine.
[0028] In this connection it should be moreover pointed out that the sliding or slipping
force can be suitably calibrated, by simply operating the nut or bolt 25, which allows
to adjust the load on the springs urging the washer which axially operates on the
cam hub.
[0029] Moreover, it should be also pointed out that the provided mechanism allows to reduce
the weight of the mechanical assembly, since it overcome the requirements of resisting
against high efforts due to the presence of obstacles.
[0030] The invention as disclosed is susceptible to several variation and modifications
all of which will come within the scope of the invention.
[0031] Moreover, all of the details can be replaced by other technically equivalent elements.
[0032] In practicing the invention, the used materials, as well as the contigent size and
shapes, can be any, according to requirements.
1. An ice cube making machine including a safety device for protecting against overloads
a tilting mechanism of a water tray thereof, said water tray being pivoted to a machine
bearing framework and coupled, through a rod, to a cam, driven by a geared motor unit,
for cyclically tilting said water tray, characterized in that said machine further
comprises clutch means, arranged between said cam and geared motor unit, for preventing
obstacles for damaging said machine during the tilting operation of said water tray.
2. A machine, according to Claim 1, characterized in that said clutch means comprise
a conic end piece keyed on an output shaft of said geared motor unit and engaging
in a conic recess provided on the hub of said cam, at an axial end portion of said
hub there being provided resilient urging means.
3. A machine, according to the preceding claims, characterized in that said machine further
comprises a cylindric end piece, with a flange keyed on the output shaft of said geared
motor unit and engaging in a cylindric recess formed on the hub of the cam, at one
axial end portion of which is provided a washer urged by resilient means.
4. A machine, according to one or more of the preceding claims, characterized in that
said resilient means comprise one or more cup springs.
5. A machine, according to one or more of the preceding claims, characterized in that
said resilient means comprise a coil spring.
6. A machine, according to one or more of the preceding claims, characterized in that
said machine comprises calibrating means for calibrating the resilient load on said
resilient means, comprising a nut element engaging with a threaded end portion of
said output shaft.
7. A machine, according to one or more of the preceding claims, characterized in that
said rod, at one end thereof, is pivoted to a middle portion of said water tray and,
at the other end portion thereof, is pivoted to the periphery of said cam, said cam
having a circular configuration and being peripherally provided with a notch therein
is engaged a geared motor unit controlling microswitch.