Abstract:
A central vacuum unit comprises a cyclonic chamber having a sidewall. A motor causes a swirl of air loaded with debris to centrifugally contact an inner surface of the sidewall of the cyclonic chamber. A lateral outlet is defined through the sidewall to provide for lateral discharge of the debris from the cyclonic chamber.

Description:
RELATED APPLICATION(S)  
       [0001]     This is a continuation of U.S. Provisional Patent Application No. 60/651,077 filed on Feb. 9, 2005. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a central vacuum unit, and more particularly to a compact central vacuum unit.  
         [0004]     2. Background Art  
         [0005]     It is common place for a central vacuum unit to be installed near or even in a living space. However, central vacuum units presently on the market come with many disadvantages. Generally, central vacuum units take up a lot of space, and more particularly vertical space. Consequently, it can be difficult to find a location to install such a unit. Ideally, an individual may want to install such a unit in a closet or in any other small enclosed area. Therefore there is a need for a more compact central vacuum unit with equivalent characteristics to the regular units on the market.  
         [0006]     Another disadvantage lies in the fact that central vacuum units tend to generate unacceptable levels of noise. Even though the prior art reveals the introduction of sound absorbing materials and mufflers as well as other means intended to reduce the levels of noise emitted by existing central vacuum units, there is still a need for a more quiet unit.  
         [0007]     A further disadvantage lies in the fact that typically central vacuum units are problematic to clean. The cage being permanently attached below the motor and the debris being collected in a canister attached below the chamber housing the motor causes the problem. When the canister is detached and removed to empty the contents thereof, any debris left on the filter covering the cage may fall to the floor. Even more, changing the filter results in a very messy outcome. Therefore, there is a strong need for a central vacuum unit that is less problematic to clean.  
         [0008]     Also, the carbon dust generated by the motor of conventional central vacuum units is discharged directly into the surrounding environment preventing the installation of such units in closets where articles of clothing or food are stored.  
         [0009]     There is thus a need for a new central vacuum unit which addresses the above-mentioned problems.  
       SUMMARY OF INVENTION  
       [0010]     It is therefore an aim of the present invention to provide a compact central vacuum unit.  
         [0011]     It is another aim of the present invention to provide a central vacuum unit that is relatively easy to clean.  
         [0012]     Therefore, in accordance with a first aspect of the present invention, there is provided a central vacuum unit comprising a cyclonic chamber having a sidewall, and a motor causing a swirl of air loaded with debris to centrifugally contact an inner surface of the sidewall of said cyclonic chamber, and a lateral outlet defined through said sidewall to provide for lateral discharge of the debris from said cyclonic chamber.  
         [0013]     In accordance with a further general aspect of the present invention, there is provided a central vacuum unit comprising a motor drawing a first flow of air along a working path, and a fan circulating a second flow of air along a cooling path, wherein the second flow of air is drawn out of the cooling path into the working path by the first flow of air before both the first and second flows be jointly discharged through a common outlet. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]     Reference will now be made to the accompanying drawings, showing by way of illustration a preferred embodiment thereof and in which:  
         [0015]      FIG. 1  is a side elevation view of a central vacuum unit in accordance with an embodiment of the present invention, the casing of the unit being illustrated as transparent to reveal the internal details of the unit.  
         [0016]      FIG. 2  is a sectioned perspective view of the central vacuum unit shown in  FIG. 1 ;  
         [0017]      FIG. 3  is a top view of the central vacuum unit shown in  FIG. 1 , the casing being once again shown as transparent for illustration purposes; and  
         [0018]      FIG. 4  is a front elevation view of the central vacuum unit shown in  FIG. 1  with the casing illustrated as transparent to permit visualization of the internal parts of the unit. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0019]     Referring now to the drawings in greater detail and by reference characters thereto, there is illustrated a preferred embodiment of a central vacuum unit identified by reference numeral  10 . The central vacuum unit  10  has a working airflow and a cooling airflow: the former being the air with particles of dust and other matter that requires cleaning, the latter being the air that cools the mechanical components thereof. The central vacuum unit  10  is of the type adapted to interact with a network of suction ducts (not shown) extending into various rooms of a building whereby each duct terminates in a suction inlet for drawing dirt and dust from in the room. The central vacuum unit  10  may also be employed as a conventional portable vacuum cleaner by attaching an extension with a nozzle thereto and manually pointing the nozzle at the area to be cleaned. Also, the central vacuum unit  10  may be utilized independently to filter the air of its surrounding environment.  
         [0020]     Referring concurrently to FIGS.  1  to  4 , the central vacuum unit  10  comprises first and second sections  12  and  14  adapted to mate in an overlapping configuration with the second section  14  overlapping the first section  12 . The first and second sections  12  and  14  may be interlocked by various attachment means such as clips and the like (not shown). Particularly, the first section  12  has a step-shaped side cross-section and the second section  14  has a corresponding inverted step-shaped cross-section.  
         [0021]     Now referring more specifically to  FIG. 1 , it can be seen that the first section  12  of the central vacuum unit  10  is made up of a front face  16 , a rear face  18 , two side faces  20  and  22  ( FIG. 4 ), horizontal and vertical step faces  24  and  26 , and is enclosed by a bottom and a top face  28  and  30  respectively. Preferably, the vertical step face, rear and side faces  26 ,  18 ,  20 ,  22  respectively are interconnected in a continuous manner with a smooth transition from one face to the other. As best illustrated in  FIG. 3 , the corners of the aforementioned faces are generally rounded while the step portion of the first section  12  is rectangular, consisting of the front face  16  intersecting the horizontal step face  24  and a portion of the bottom face  28  and side faces  20  and  22 . Furthermore, the confines of the interconnected faces of the first section  12  define a hollow space  32  ( FIG. 2 ). The first section  12  is compartmentalized such that the hollow space  32  is divided into chambers. Particularly, a central horizontal partition  34  divides the hollow space  32  into an upper chamber  36  and a lower chamber  38 . Both the upper and lower chambers  36  and  38  are preferably lined with sound absorbing material (not shown), the lining keeping with the smooth contours of the faces. For example, acoustic foam may be utilized as an acoustic dampening means.  
         [0022]     Referring particularly to  FIG. 2 , the upper chamber  36  houses a central by-pass motor  40  which creates the suction force required for the central vacuum unit  10  to be operational. The motor  40  is encircled by a perforated cylindrical partition  42  extending the height of the upper chamber  36  between the top face  30  and the horizontal partition  34 . An exhaust pipe  44  ( FIG. 3 ) departing tangentially from the motor  40  extends outwards through the perforated cylindrical partition  42  but remains within the confines of the first section  12  in the upper chamber  36 . The exhaust pipe  44  is preferably an elbow pipe for redirecting airflow in the tangential direction around the exterior of the perforated cylindrical partition  42 .  
         [0023]     Still referring to  FIG. 2 , the lower chamber  38  houses a fan  46  for cooling the motor  40 . In this preferred embodiment, the fan  46  is disposed beneath the motor  40  in line therewith and exposed thereto by way of an opening  48  in the horizontal partition  34 . The opening  48  is preferably centrally located beneath the motor  40 . According to another embodiment, a through-flow motor could be used in place of a by-pass motor and a fan.  
         [0024]     Moreover, the fan  46  is partially enclosed by a surrounding wall  50  preferably extending the height of the lower chamber  38  between the horizontal partition  34  and the bottom face  28 . The surrounding wall  50  includes an entrance  52  allowing for an airflow originating from a cooling air inlet  54  to enter within the confines thereof. The cooling air inlet  54  for admitting air into the lower chamber  38  may be a perforated floor section  56  in the bottom face  28  of the first section  12 .  
         [0025]     Naturally, the cooling air inlet  54  may consist of other means and may be located elsewhere. However, it is preferable that the entrance  52  be positioned away from the cooling air inlet  54  so as to reduce the noise level generated by the fan  46  as will be explained in detail furtheron. In the exemplary embodiment illustrated in  FIG. 2 , the entrance  52  of the surrounding wall  50  is facing the front face  16  while the perforated floor section  56  is adjacent the rear face  18  behind the surrounding wall  50 .  
         [0026]     Referring to  FIG. 2 , an exhaust port  58  is situated in the lower chamber  38  disposed in the rear face  18 . An elbow duct  60  extends from the exhaust port  58  to an aperture  62  in the central horizontal partition  34  allowing for flow communication therebetween.  
         [0027]     Now referring to  FIG. 1 , first and second working air intake ports  64  and  66  situated in the lower chamber  38  of the first section  12  are shown. The first working air intake port  64  is disposed on the rear face  18  and is intended to be joined to a principal duct (not shown) of the network of suction ducts aforementioned. Naturally, the first intake port  64  may be plugged if not used.  
         [0028]     The second working air intake port  66  is disposed on the front face  16  and is intended to be in flow communication with an extension attached thereto: the extension for use as a manual cleaning device as above-described. Preferably, when not being employed, the second intake port  66  is blocked by way of a cap  68  as best shown in  FIG. 1 .  
         [0029]     Still referring to  FIG. 1 , it can be seen that extending from the first and second intake ports  64  and  66  within the lower chamber  38  are first and second suction ducts  70  and  72  respectively. The ducts  70  and  72  amalgamate at a junction point  74  whereby a third suction duct  76  emerges extending vertically from the lower chamber  38  through the central horizontal partition  34  to an aperture  78  in the top face  30  of the first section  12 . Thus, airflow may be communicated from the first and second air intake ports  64  and  66  to the aperture  78  in the top face  30  of the first section  12 .  
         [0030]     Moreover, the first section  12  houses in the forefront of the lower chamber the electrical controls (not shown) of the central vacuum unit  10 . Switches (not shown) for activating and deactivating the central vacuum unit  10  may be operably connected to the controls. The switches may be located at any desired location on the central vacuum unit  10 . However, it is understood that the unit could be actuated by other suitable means and as such it could be devoid of any switch.  
         [0031]     Now referring to the second section  14  of the central vacuum unit  10  as shown in  FIGS. 1 and 2 , it can be seen that the second section  14  is adapted to mate with the first section  12  in an overlapping arrangement. The second section  14  is also made up of a front face  80 , a rear face  82 , two side faces  84  and  86 , horizontal and vertical step faces  88  and  90 , and is enclosed by a bottom and a top face  92  and  94  respectively. Preferably, the rear and side faces  82 ,  84 ,  86  respectively are interconnected in a continuous manner with a smooth transition from one face to the other. As best illustrated in  FIG. 3 , the corners of the aforementioned faces are generally rounded while the step portion of the second section  14  consisting of the horizontal step face  88  intersecting the vertical step face  90  and a portion of the front face  80  is rectangular.  
         [0032]     Notably, the bottom face  92  of the second section  14  is designed to sit upon the top face  30  of the first section  12 . Also, the horizontal and vertical step faces  88  and  90  of the second section  14  are configured to match up with the horizontal and vertical step faces  24  and  26  of the first section  12  when in an overlapping arrangement.  
         [0033]     Moreover, the confines of the interconnected faces of the second section  14  define a hollow space  96 . The second section  14  is compartmentalized such that the hollow space  96  is divided into chambers. Particularly, a pair of smoothed partitions  98  and  100  ( FIG. 3 ) extend towards the front face  80  within the side faces  84  and  86  respectively mirroring the curvature of the rounded corners of the interconnected rear  82  and side faces  84  and  86  ( FIG. 3 ). The smoothed partitions  98  and  100  curve towards each other so as to form a relatively symmetrical cylindrical chamber that will be referred to from hereon as the cyclonic chamber  104 .  
         [0034]     Referring to  FIG. 3 , it can be seen that the smoothed partitions  98  and  100  are separated by a gap  102 , the latter preferably opposing the rear face  82  of the second section  14 . As will be seen hereinafter, the gap  102  provides a lateral discharge for the cyclonic chamber  104 . Furthermore, the smoothed partition  98  has a deflector  106  ( FIGS. 1 and 2 ) disposed thereon. The deflector  106  is located at the end of the smoothed partition  98 , adjacent the gap  102 , extending inwardly with respect to the confines of the cyclonic chamber  104 . Preferably the deflector  106  is angled towards the gap  102  as shown in  FIG. 3 .  
         [0035]     Now referring concurrently to FIGS.  1  to  4 , the cyclonic chamber  104  houses a cylindrical cage  108  for supporting a filter (not shown) of the type designed to cover the cage  108 . The cage  108  is aligned with the motor  40  and preferably centered within the cyclonic chamber  104  and attached to the bottom face  92  thereof. In an exemplary embodiment, the cage  108  is attached to a removable portion  110  of the bottom face  92  of the second section  14 . Particularly in  FIG. 3 , the removable portion  110  is shown as a circular portion greater in diameter than that of the cage  108 . Therefore, the cage  108  may be removed from within the cyclonic chamber  104  when the second section  14  is removed from over top the first section  12  by detaching the removable portion  110  from the bottom face  92  and retracting the cage  108  thereby. Notably, the removable portion  110  may be secured to the bottom face  92  by way of various attachment means  112  such as screws and the like.  
         [0036]     Referring to FIGS.  1  to  4 , it is shown that the cage  108  is centered over a screen  114  disposed in the top face  30  of the first section  12 . A second overlapping screen (not shown) could be disposed in the bottom face  92  of the second section  14 . The first and second screens allow for flow communication between the first and the second sections  12  and  14  to take place.  
         [0037]     More particularly, the first screen  114  is circumscribed by the perforated cylindrical partition  42  acting as a working air inlet for the motor  40  as will be explained in detail furtheron. The second screen could be part of the removable portion  110 .  
         [0038]     Furthermore, the cyclonic chamber  104  has an aperture  118  ( FIG. 3 ) in the bottom face  92  in line with the aperture  78  in the top face  30  of the first section  12  previously disclosed. Preferably extending from the aperture  118  in the cyclonic chamber  104  is an elbow duct  120  ( FIG. 2 ) for redirecting the airflow in the tangential direction about the cage  108 .  
         [0039]     Adjacent the cyclonic chamber  104  and disposed in the forefront of the second section  14  on the opposite side of the smoothed partitions  98  and  100  is a debris collecting chamber  122 . The debris collecting chamber  122  is delimited by the front face  80 , the horizontal and vertical step faces  88  and  90 , a portion of the side faces  84  and  86  and the exterior of the smoothed partitions  98  and  100 . The gap  102  between the smoothed partitions  98  and  100  acts as a passageway between the cyclonic chamber  104  and the debris collecting chamber  122 .  
         [0040]     Referring to  FIG. 2 , the debris collecting chamber  122  may be provided with a trap door  124  disposed in the bottom thereof, particularly in the horizontal step face  88 . The trap door  124  can be utilized to dispose of the contents that accumulate in the debris collecting chamber  122  when the central vacuum unit  10  is in operation. Notably, the second section  14  must be removed from on top of the first section  12  to access the trap door  124 .  
         [0041]     Preferably, the debris collecting chamber  122  has a window (not shown) located in one of the faces: the window allowing verifying the amount of debris present in the chamber  122 .  
         [0042]     Furthermore, the central vacuum unit  10  is adapted for use with a wall installation kit (not shown). The kit includes a metal box having an air intake duct, an exhaust duct and a flange. The metal box is designed for installment within a wall such that only the flange extends out of the wall. The rear side-by-side air intake port  64  and the exhaust port  58  are adapted to be abutted in flow communication with the principal ducts of the network of suction ducts running through the walls of a building as previously described. The central vacuum unit  10  has a hook  126 , as illustrated in  FIG. 1  to  3 , for hooking into a slot in the flange of the box such that the first working air intake port  64  and the exhaust port  58  abut the air intake and exhaust ports of the box respectively to for a but joint therewith. Therefore, the central vacuum unit  10  is adapted for installation on a wall by way of attachment to the box.  
         [0043]     Now, the working airflow and cooling airflow paths of the central vacuum unit  10  with respect to the above-described components will be described in detail. In the case of the working air flow, the motor  40  of the central vacuum unit  10  creates a suction force so as to draw working air into the unit  10 . The working air is admitted into the central vacuum unit  10  from either the first and/or the second working air intake ports  64 ,  66 . Then the working air flows through the first and/or second suction ducts  70 ,  72  to the third suction duct  76  which redirects the working air upwardly out of the first section  12  of the central vacuum unit  10 . Thus, the working air exits the aperture  78  in the top face  30  of the first section  12  and enters the cyclonic chamber  104  of the second section  14  through the aperture  118  in the bottom face  92  thereof. The working air is then redirected by the elbow duct  120  to flow around the cyclonic chamber  104  such that the flow is tangential to the cage  108 .  
         [0044]     Thus, a cyclonal effect is created within the cyclonic chamber  104 . The working air is consequently subjected to a centrifugal force such that a majority of the air and debris is forced towards the faces of the cyclonic chamber  104 . More specifically, the whirlwind that is created causes a majority of the debris including dust particles and other matter in the working air to move radially outwards only to be contained by the faces of the cyclonic chamber  104 . When the debris reaches the gap  102  between the smoothed partitions  98  and  100  and makes contact with the deflector  106 , it is subsequently deflected laterally. Preferably, the debris is laterally deflected into the debris collecting chamber  122 .  
         [0045]     The debris accumulates in the debris collecting chamber  122  until it is emptied whereby the trap door  124  is opened so that the debris may be disposed of. Advantageously, collecting the debris in a chamber  122  separate from the chambers housing the cage  108  and the motor  40  eliminates the loss of vacuum or suction force. More specifically, the vacuum force derived from the motor  40  may be maintained at a high level when the filter (not shown) on the cage  108  remains unblocked. Thus, in the present embodiment the debris collecting chamber  122  may be filled up until the height of the vertical step portion  90  without hindering the performance of the motor and more specifically the vacuum force. After this point however, the debris may begin to fill the cyclonic chamber  104  rather than remain in the debris collecting chamber  122  and consequently affect the vacuum force.  
         [0046]     Moreover, the vacuum force created by the motor  40  sucks a portion of the working air in the center of the cyclonic chamber  104  into the cage  108  through the filter thereon. The filtered working air then enters the upper chamber  36  within the confines of the perforated cylindrical partition  42  and is inhaled by the motor  40 . The latter ejects the air out through the exhaust pipe  44  such that it flows around the upper chamber  36  outside the perforated cylindrical partition  42 . Thus, the noise level generated may be dampened by having the air flow around the motor  40  before exhausting it from the central vacuum unit  10 .  
         [0047]     After circling around the upper chamber, the air is then exhausted by way of the aperture  62  in the horizontal partition, through the elbow duct  60  in the lower chamber  38 , and out the exhaust port  58 . The exhaust port  58  may be adjoined to a exhaust receiving duct (not shown) that directs the air through the walls of a building to an exterior environment, or the exhaust port  58  may be covered by a filter (not shown) and exposed to the immediate environment.  
         [0048]     In the case of the cooling air, the fan  46  draws cooling air into the central vacuum unit  10  through the cooling air inlet  54 . The cooling air then travels around the exterior of the surrounding wall  50  of the fan  46  and in through the entrance  52  leading to the fan  46 . It is preferable that the cooling air surrounds the surrounding wall  50  so as to dampen the noise generated by the fan  46 .  
         [0049]     The fan  46  inhales the cooling air redirecting it upwardly into the motor  40  through the opening  48  in the horizontal partition  34 . Hence, the cooling air cools the motor  40  as it circulates within the confines of the perforated cylindrical partition  42 .  
         [0050]     Furthermore, the cooling air is then drained out through the perforations in the partition  42  due to an existing pressure difference between the region outside of the partition and the region within the partition. As the pressure of the outside region is less than that of the inside region, naturally the cooling air is induced to flow radially outwards through the perforations from a region of high pressure to a region of low pressure. The cooling air is drawn out of the central space circumscribed by the perforated partition  42  by the flow of working air discharged from the motor  40 . The cooling air then mixes with the filtered working air flowing around the partition  42 . The mixture of both the filtered working air and the cooling air is then exhausted out of the central vacuum unit  10  via the exhaust port  58  as previously explained.  
         [0051]     Advantageously, having the cooling air drain out through the perforated cylindrical partition  42  increases the overall heat transfer whereby heat is eliminated from the motor  40 . Therefore, the motor  40  may perform with greater efficiency as the heat eliminated is maximized. Also, it is preferable to have the cooling air mix with the filtered working air and be expulsed thereafter so as to eliminate the need for any additional components that may be required to exhaust the cooling air separately. This also advantageously allows to trap and evacuate the carbon dust generated by the motor  40  in the outgoing flow of working air and cooling air through the outlet  58  and into the duct network of the apartment or the house, thereby preventing release of carbon dust in the immediate environment of the central vacuum unit  10 .  
         [0052]     As should be apparent from the above detailed description, the present invention provides significant advantages over existing central vacuum units. Another advantage being that the central vacuum unit  10  is compact in the vertical direction which enables it to fit into places where other existing central vacuum units cannot fit. The debris collecting chamber  122  is located laterally rather than vertically with respect to the chambers housing the cage  108  and motor  40 , thus resulting in a more compact unit configuration. The above described embodiment is also advantageous in that it has a debris collecting chamber  122  which is separate from the chambers housing the cage  108  and the motor  40 , thereby preventing premature clogging of the filter and thus rapid loss of suction power.  
         [0053]     A further advantage being that it is easy to clean. Firstly, this is due to the fact that the cage  108  does not remain attached to the motor  40  when the debris collecting chamber  122  is removed in order to be emptied. The central vacuum unit  10  has detachable separate first and second sections  12 ,  14 . Thus, the second section  14  may be entirely removed from the first  12  and transported to the disposal area to avoid any mishaps when disposing of the debris. The debris is collected in a chamber separate from the chamber housing the cage  108  and filter; therefore, the debris collecting chamber  122  may be emptied without exposing the cage  108  and filter thereon. Since the filter conventionally does not need to be changed as often as the debris must be disposed of, the cleaning procedure is shortened and facilitated. Thirdly, when the filter does necessitate changing, the cage  108  may be removed by way of the removable portion  110  in the bottom face  92  of the second section  14 . Once removed, the cage  108  may be easily cleaned over a trash can or the like.  
         [0054]     Still another advantage being that the motor  40  is disposed below the cage  108 . This component orientation in combination with the above described features enables the central vacuum unit  10  to overcome some of the disadvantages previously set forth.  
         [0055]     Still a further advantage being that the present invention with safety in mind. Due to the fact that the motor  40  is entirely enclosed in the first section  12 , the motor  40  remains covered even when the second section  14  is detached from the first  12 .  
         [0056]     Yet another advantage being that the present invention can be sold as a kit including: the central vacuum unit  10  and the wall installation kit.  
         [0057]     Although the present central vacuum unit has been described with a certain degree of particularity, it is to be understood that the disclosure has been made by way of example only and that the present invention is not limited to the features of the embodiments described and illustrated herein, but includes all variations and modifications within the scope of the invention as hereinafter claimed.