Patent Publication Number: US-2022225818-A1

Title: Coffee grinder with low acoustic impact

Description:
The present invention refers to a coffee machine with reduced acoustic emission and to a soundproofing process for soundproofing a coffee machine. 
     Automatic coffee machines present on the market are particularly noisy during the preparation and dispensing of the drink. 
     The main sources of noise can be attributed to the activation of the water pump, the grinding of the beans and the movement of the brewing unit. Among these, the grinding of the beans is the most significant source of noise. 
     Automatic coffee machines of the known type comprise a hopper of coffee beans, a grinder and a brewing unit housed in a compartment of the coffee machine frame. Normally, the grinder is positioned in the rear part of the coffee machine interposed between the hopper and the brewing unit. During operation, the grinder receives the coffee beans to be ground from the hopper and dispenses the ground coffee powder to the brewing unit through a relevant rigid contact. 
     During the coffee bean grinding step, the grinder develops vibrations that are transmitted to the other components in contact therewith, the hopper, conduit and frame of the machine, and the sound waves are amplified by the large and uninterrupted empty spaces present in the housing compartment of the hopper, grinder and brewing unit. 
     The only anti-vibration elements usually present in coffee machines are dampening elements positioned in the support points of the grinder with the frame. The remaining components are rigid and in connection with each other, therefore the vibrations emitted by the grinder are transmitted to the components generating noise. 
     To overcome the high degree of noise, in recent years, some rigid components have been replaced with others made of rubber material such as, for example, the dispensing conduit of the coffee ground by the grinder to the brewing unit, and anti-vibration gaskets have also been introduced between the hopper and the grinder and acoustic insulation panels above the grinder. 
     However, these modifications suffer from numerous disadvantages. 
     In the first place, a plurality of separate and distinct anti-vibration elements leave empty spaces in the housing compartment around the grinder and above it in which the sound waves and vibrational waves can resonate and act as sound amplification speakers. 
     In the second place, the plurality of separate elements makes the assembly difficult in terms of time and the manufacturing thereof disadvantageous in terms of costs. Furthermore, the use of distinct and separate anti-vibration elements allows not only the propagation of vibrations but also the heat produced by the grinder and the steam produced by the brewing unit to reach the hopper of coffee beans heating it, ruining the organoleptic properties of the coffee beans. 
     Likewise, a further disadvantage of the use of distinct and separate anti-vibration elements is that of having numerous joints that allow the spread of dust and reduce the degree of cleanliness inside the coffee machine. 
     An object of the present invention is to realise a coffee machine that solves the mentioned problems of the prior art, in particular that limits the propagation of the vibrations generated by the grinder. 
     A further object of the present invention is that of providing a coffee machine with improved preservation performance for the coffee beans of the hopper with respect to what is known in the state of the art. 
     Another object of the present invention is also to realise a coffee machine having a high degree of internal cleanliness. 
     Finally, the object of the present invention is to soundproof a coffee machine simply and effectively. 
     The technical task, as well as these and other objects according to the present invention are achieved by realising a coffee machine comprising a brewing unit, a hopper for containing a plurality of coffee beans, a grinder for grinding coffee beans, a frame comprising a compartment, said compartment having a zone for housing said hopper, a zone for housing said grinder and a zone for housing the brewing unit, characterised in that it comprises a shaped elastomeric membrane for sound insulation positioned in said compartment and extending below said hopper to fill the empty space present in said compartment. 
     Advantageously, the membrane interrupts the continuity of the empty space present inside the compartment. 
     Advantageously, the membrane is interposed between the hopper and the grinder. Advantageously, the membrane comprises a first through opening connecting an unloading mouth of the coffee beans of the hopper and a receiving mouth of coffee beans of the grinder. 
     Advantageously, the membrane comprises a first gasket that extends perimetrally to the first opening for the seal between the unloading mouth and the receiving mouth. 
     Advantageously, the housing zone for housing the hopper comprises a perimeter shoulder and the membrane perimetrally has a second gasket engaged with said shoulder. 
     Advantageously, the membrane comprises a primary conduit for conveying to the brewing unit the coffee powder dispensed by the grinder comprising an inlet opening and an outlet opening. 
     Advantageously, the membrane comprises a third inlet gasket that sealingly connects said inlet opening with a dispensing mouth of the coffee powder of the grinder. 
     Advantageously, the primary conveying conduit is positioned through an opening of the compartment that connects the housing zone of the brewing unit and the housing zones of the hopper and the grinder. 
     Advantageously, the membrane comprises a fourth gasket that extends perimetrally outside the conveying conduit for the seal with the opening of the compartment. Advantageously, the membrane comprises a secondary conveying conduit of the coffee powder to the brewing unit and a fifth perimeter gasket of said secondary conduit for the sealing connection thereof with a slide for the manual loading of coffee powder. 
     Other characteristics of the present invention are also defined in the following claims. 
    
    
     
       Further characteristics and advantages of the invention will become more apparent from the description of a preferred, but not exclusive, embodiment of the coffee machine, which is illustrated by way of approximate and non-limiting example in the attached drawings, of which: 
         FIG. 1  shows an exploded view of the coffee machine, which is the object of the present invention, in accordance with an embodiment; 
         FIG. 2  shows a first section of the coffee machine of  FIG. 1  assembled, in accordance with an embodiment; 
         FIG. 3  shows a second section of the coffee machine of  FIG. 1  assembled, in accordance with an embodiment. 
     
    
    
     With reference to the figures cited, a coffee machine is shown, which is generally indicated by number  1 . 
     The coffee machine  1  comprises a brewing unit (not shown), a hopper  2  containing a plurality of coffee beans equipped with an unloading mouth  7  for unloading the coffee beans and a grinder  3  for grinding the coffee beans equipped with a receiving mouth  8  for receiving the coffee beans. 
     The coffee machine  1  comprises a frame  4  that has a compartment  5 . 
     The compartment  5  has a housing zone for housing the hopper  2 , a housing zone for housing the grinder  3  and a housing zone for housing the brewing unit. 
     The grinder  3 , fixed to the frame, is positioned in the compartment  5  in an interposed position between the hopper  2  and the brewing unit. 
     According to a particular aspect of the invention the coffee machine  1  comprises a shaped elastomeric membrane  6  for sound insulation positioned in the compartment  5 . 
     The membrane  6  extends below the hopper  2  filling the empty space present in the compartment  5 . 
     The membrane  6  in particular is interposed between the hopper  2  and the grinder  3 . Advantageously, the membrane  6  forms a physical barrier to the propagation of the vibrations and noise generated by the grinder when it is operating. 
     The membrane  6  comprises a first through opening  9  connecting the unloading mouth  7  of the hopper  2  and the receiving mouth  8  of the grinder  3 . 
     Advantageously, the membrane  6  comprises a first gasket  10  that extends perimetrally to the first opening  9  for the sealing connection between the unloading mouth  7  of the hopper  2  and the receiving mouth  8  of the grinder  3 . 
     Preferably, the first gasket  10  is a bellows gasket. 
     In particular, the first gasket  10  is positioned outside the unloading mouth  7  and inside the receiving mouth  8 . 
     According to a particular aspect of the invention, the membrane  6  has a concave portion surrounding a lower portion of the hopper including the unloading mouth  7 . 
     It is to be noted that the housing zone for housing the hopper  2  comprises a perimeter shoulder  11 , which is preferably flat. 
     Even more preferably, the perimeter shoulder  11  extends along a closed line that perimetrally delimits the upper end of said compartment  5 . 
     The membrane  6  perimetrally has a second gasket  12 , particularly but not necessarily with a U-shaped section, engaged with the shoulder  11 . 
     In particular, the second gasket  12  delimits an upper end of the membrane  6 . 
     In a preferred embodiment, the second gasket  12  extends from a flat perimeter flange  30  of the membrane  6  conjugated to the shoulder  11 . 
     It is to be noted that the coffee machine  1  comprises a closing cover  13  for closing the compartment  5 . 
     The cover  13  clamps the second gasket  12  against the shoulder  11 . 
     In a preferred embodiment, the hopper  2  is supported in a fixed way by said cover  13 . 
     The first gasket  10  enables the vibrations transmitted to the hopper  2  to be dampened while the second gasket  12  allows the vibrations transmitted to the cover  13  to be dampened, whereas the membrane  6 , thanks to its position interposed between the hopper  2 , the grinder  3  and the frame  4 , reduces the empty space present in the compartment and interrupts the continuity of the empty space present in the compartment between the hopper  2  and the grinder  3  so as to limit the amplification and propagation upwards of the sound waves generated by the grinder. 
     Advantageously, on one hand, the membrane  6 , thanks to the first gasket  10  and the second gasket  12 , forms not only a physical barrier for the propagation of noise but also a thermal insulation barrier for the heat generated by the motor of the grinder  3 . 
     Therefore, the membrane  6  also allows the organoleptic properties of the coffee beans contained in the hopper  2  to be left unaltered. 
     Preferably, the membrane  6  comprises a primary conduit  15  for conveying to the brewing unit the coffee powder dispensed by the grinder  3 . 
     In particular, the primary conduit  15  is equipped with an inlet opening  16  and an outlet opening  31 . 
     The outlet opening  31  of the primary conduit  15  faces the housing zone of the brewing unit for loading a brewing chamber. 
     The membrane  6  has a third gasket  17  perimetral to said inlet opening  16  that sealingly connects the inlet opening  16  with the dispensing mouth  14  for dispensing the ground coffee powder to the brewing unit normally provided by the grinder  3 . 
     Preferably, the third gasket  17  is a lip seal gasket connected to the dispensing mouth  14  of the grinder  3 . 
     Thanks to the primary conduit  15  and the third sealing gasket  17  with the dispensing outlet of the grinder, the membrane  6  further reduces the propagation spaces of the noise generated by the grinder. 
     The third gasket  17  also prevents the dispersion of coffee powder into the compartment  5 . 
     According to an embodiment, the compartment  5  comprises an opening  18  connecting the housing zone for housing the brewing unit and the housing zones for housing the hopper  2  and the grinder  3 , and the primary conduit  15  is positioned through said connection opening  18 . 
     Preferably, the membrane  6  comprises a fourth gasket  19  that extends perimetrally outside the conveying conduit  15  for the sealing connection with the opening  18  of the compartment  5 . 
     Preferably, the fourth gasket  19  is a lip seal gasket. 
     The fourth gasket  19  separates the housing zone for housing the grinder from the housing zone for housing the brewing unit and, as well as further reducing the propagation of noise of the grinder, it represents a barrier against steam rising into the compartment  5 . 
     According to a further preferred embodiment, the coffee machine comprises a slide  20  for the manual loading of coffee powder, and the membrane  6  comprises a secondary conveying conduit  21  for conveying the coffee powder to the brewing unit. 
     In particular, the membrane  6  comprises a fifth perimeter gasket  22  of said secondary conduit  21  for the sealing connection thereof with the slide  20 . Preferably, the fifth gasket  22  is a lip seal gasket. 
     Preferably, the fifth gasket  22  extends inside the secondary conveying conduit  21  and sealingly connects it with a tubular shaped unloading outlet of the slide  20 . According to a preferred embodiment, the slide  20  is supported by the cover  13 . The secondary conveying conduit  21  flows into the primary conveying conduit  15 . Therefore, the membrane  6 , sealingly connected with the opening  18  of the compartment  5  thanks to the fourth gasket and sealingly connected with the slide  20  thanks to the fifth gasket  22 , forms together with the slide  20  a preferential conveying conduit towards the outside of the coffee machine  1  of the steam emitted by the brewing unit during the operation thereof. 
     In other words, the membrane forms a physical barrier that prevents the steam emitted by the brewing unit from reaching the hopper and compromising the organoleptic qualities of the coffee beans contained in the hopper. 
     The present invention further relates to a soundproofing process for soundproofing the coffee machine  1 . 
     The process comprises the step of introducing into the compartment  5  reaching below the hopper  2 , the shaped elastomeric membrane  6 , interposing it between the grinder  3 , the frame  4  and the hopper  2  to fill the empty space present in the compartment  5 . 
     The process comprises the step of forcing the shaped elastomeric membrane  6  to deform to be fitted sealingly into related seats provided in the components of the coffee machine  1 . 
     In particular, according to the present soundproofing process, the membrane  6  is forced to deform to be fitted sealingly between the unloading mouth  7  of the hopper  3  and the receiving mouth  8  of the grinder  3 , with the dispensing mouth  14  of the grinder  3  and with an opening  18  of the compartment that connects the housing zone of the brewing unit and the housing zones of the hopper and the grinder. 
     Advantageously, the provision of a single multifunctional elastomeric membrane  6  makes the soundproofing process extremely simple and intuitive to perform, and the assembly step quick and easy to implement. 
     The elastomeric membrane can be made for example of silicone or another type of rubber. 
     The coffee machine  1  as conceived herein is susceptible to many modifications and variations, all falling within the scope of the inventive concept; furthermore, all the details are replaceable by technically equivalent elements. In practice, the materials used, as well as the dimensions, can be any according to the needs and the state of the art.