Patent Description:
In commercial cooking applications, the ventilation hood system can become caked with grease and should be cleaned periodically. Often, the cleaning schedule is based on a standard time period when a certain amount of grease is expected to be deposited from grease-laden cooking vapors and can lead to cleanings that are either done before an excessive amount of grease has been deposited or cleanings that are delayed. That is, if the cleanings are scheduled regularly and without reference to actual grease levels, there exists a potential that the hood is cleaned more or less often than needed. If the cleanings are too frequent, the cleanings can be a costly and time-consuming whereas if the cleanings are too infrequent there could be a time period where the hood has more than a safe amount of grease deposition.

While spot-check sensors are available for checking grease levels, such spot-check sensors do not provide indications of how much grease is present in a whole ventilation hood system.

<CIT> discloses an example of an ventilation hood system comprising a hood body, a collection cup and a weight sensor, wherein weight data of grease inside the collection cup is collected to remind the user to clean the hood.

According to the invention, a ventilation hood system is provided as defined by claim <NUM>.

Each of the one or more support legs may be located at a corner of the hood body.

Each of the one or more support legs may include a first load bearing member affixed at a first end thereof to the hood body, a second load bearing member affixed at a first end thereof to the fixed body and a bracket connecting respective second ends of the first and second load bearing members.

Each weight sensor may be configured to sense a portion of the entire weight of the hood body which is supported by the corresponding one of the one or more support legs.

Each weight sensor may include at least one of a load cell and a strain gauge.

Each weight sensor may be operably interposed between the first load bearing member and the bracket of the corresponding one of the one or more support legs.

The weight sensing system may further include a spot-check sensor configured to execute spot-checks of the hood body and the weight monitor may be further configured to take the action toward cleaning the hood body in an event the spot-check sensor indicates that the action should be taken irrespective of the changes indicating that the entire weight of the hood body exceeds the predefined level.

As will be described below, a system of load-cells is installed in a ventilation hood system (e.g., a commercial ventilation hood system) such that a total weight of the vent hood body can be sensed or measured and monitored over time. By way of a comparison between the measured weight and a baseline value, which is taken when the vent hood body is clean, a value of how much weight the vent hood body has gained over time can be determined. As it can be inferred that this weight gain would be at least partially due to a deposition of grease and other similar materials onto the inner surfaces of the vent hood body, the weight gain could be used to determine if the vent hood body is due for a cleaning.

With reference to <FIG> and to <FIG>, a ventilation hood system <NUM> is provided. The ventilation hood system <NUM> may be configured as a commercial ventilation system that can be used in a commercial kitchen of a restaurant or a hotel, for example. The ventilation hood system <NUM> includes a hood body <NUM>. The hood body <NUM> includes duct sidewalls <NUM> and a screen <NUM>. The duct sidewalls <NUM> are cooperatively formed to define and enclose an interior <NUM> through which cooking vapors or other vapors are passable. The cooking vapors can be generated by cooking operations conducted on a stove or another similar device located approximately beneath the hood body <NUM> and then driven through the interior <NUM> by a fan element or blower that is installed in or adjacent to the interior <NUM>. The screen <NUM> is disposed in the interior <NUM> and is supported therein by the duct sidewalls <NUM>. The screen <NUM> may include screening or filtering media and is positioned such that the cooking vapors pass through the screening or filtering media prior to being exhausted to an exterior.

As the cooking vapors often carry or are suffused with grease, the grease can be deposited on interior surfaces of the duct sidewalls <NUM> and the screen <NUM> over time. This leads to the duct sidewalls <NUM> and the screen <NUM>, which have an initial or baseline weight when they are clean (see <FIG>), having an increased weight when they are dirty and in need of being cleaned but not necessarily periodically cleaned (see the extended legs <NUM> in <FIG> and the compressed weight sensing system <NUM> of <NUM>). Thus, the following description relates to system components and methods that are directed toward measuring a weight gain of the hood body <NUM> as grease and other foreign materials or debris become caked on the interior surfaces of the duct sidewalls <NUM> and the screen <NUM> so that the entire weight of the hood body <NUM> increases over time and then making a determination as to when cleanings should be scheduled based, in at least some cases, at least partially on the weight gain of the hood body <NUM>.

The ventilation hood system <NUM> further includes a support system <NUM> and a weight system <NUM>. The support system <NUM> is generally affixed to a fixed body <NUM> (see <FIG> and <FIG>) and is supportive of an entire weight of the hood body <NUM>. The weight sensing system <NUM> is operably coupled to the support system <NUM> and is configured to sense and monitor the entire weight of the hood body <NUM> over time.

In accordance with embodiments, the support system <NUM> includes one or more support legs <NUM>. In cases in which the support system <NUM> includes only one support leg <NUM>, the support leg <NUM> may be disposed in or proximate to a center of gravity of the hood body <NUM>. In cases in which the support system <NUM> includes multiple support legs <NUM>, the multiple support legs <NUM> may be positioned so as to support the hood body <NUM> substantially evenly. For example, in a case in which the support system <NUM> includes four support legs <NUM>, the four support legs <NUM> may be respectively disposed at corresponding corners of the hood body <NUM>.

Although the support system <NUM> can include one or more support legs <NUM>, the following description will relate to the case in which the support system <NUM> includes a support leg <NUM> at each corner of the hood body <NUM> (see <FIG>). This is done for purposes of clarity and brevity and is not intended to otherwise limit a scope of the disclosure.

As shown in <FIG> and <FIG>, each of the support legs <NUM> includes a first load bearing member <NUM>, a second load bearing member <NUM> and a bracket <NUM>. The first load bearing member <NUM> has first and second opposite ends <NUM> and <NUM> and a head <NUM> at the second end <NUM>. The first load bearing member <NUM> is affixed to the hood body <NUM> at the first end <NUM>. The second load bearing member <NUM> has first and second opposite ends <NUM> and <NUM> and a head <NUM> at the second end <NUM>. The second load bearing member <NUM> is affixed to the fixed body <NUM> at the first end <NUM>. The bracket <NUM> is configured to connect respective second ends <NUM> and <NUM> of the first and second load bearing members <NUM> and <NUM> by way of mechanical interference between the heads <NUM> and <NUM> and first and second opposite end walls <NUM> and <NUM> of the bracket <NUM>.

Each support leg <NUM> supports a portion of the entire weight of the hood body <NUM>.

The weight sensing system <NUM> includes weight sensors <NUM> that are respectively disposed in the bracket <NUM> of a corresponding support leg <NUM>. Each weight sensor <NUM> may include or be provided as at least one of a load cell and a strain gauge and is configured to sense the portion of the entire weight of the hood body <NUM> which is supported by the corresponding support leg <NUM>. In accordance with embodiments, each weight sensor <NUM> may be operably interposed between the head <NUM> of the first load bearing member <NUM> and the first end wall <NUM> of the bracket <NUM> of the corresponding support leg <NUM> or between the second end wall <NUM> of the bracket <NUM> and the head <NUM> of the second load bearing member <NUM> of the corresponding support leg <NUM>.

In either case, when the hood body <NUM> is clean and has its initial or baseline weight, each weight sensor <NUM> experiences an initial or baseline compressive load (see <FIG>). Conversely, when the hood body <NUM> is dirty and has an increased weight, each weight sensor <NUM> experiences an increased compressive load (see <FIG>). As such, while the initial or baseline compressive load of <FIG> can be used to derive the initial or baseline weight of the hood body <NUM>, the increased compressive load of <FIG> can be used to derive the increased weight of the hood body <NUM> and to determine a cleanliness condition of the hood body <NUM>.

With reference to the cantilevering of <FIG>, the cantilevering of <FIG> and opposed cantilevering of <FIG>, alternative embodiments of the ventilation hood system <NUM> are illustrated. As shown in <FIG>, the hood body <NUM> can be supported at an upper edge thereof by lateral support legs <NUM> and at a lower edge thereof by a hinge <NUM> such that the lateral support legs <NUM> are placed in tension and the corresponding weight sensors <NUM> experience compression loading as described above to effectively sense a weight of the hood body <NUM>. As shown in <FIG>, the hood body <NUM> can be supported at a lower edge thereof by lateral support legs <NUM> and at an upper edge thereof by a hinge <NUM> such that the lateral support legs <NUM> are placed in compression and the corresponding weight sensors <NUM> experience torsional loading in a configuration that is generally opposite from what is described above but should be apparent to one of ordinary skill in the art to effectively sense a weight of the hood body <NUM>. As shown in <FIG>, the hood body <NUM> can be supported at a lower edge thereof by lateral support legs <NUM> and at an upper edge thereof by lateral support legs <NUM> such that the lateral support legs <NUM> are placed in compression and the corresponding weight sensors <NUM> experience the torsional loading while the lateral legs <NUM> are placed in tension and the corresponding weight sensors <NUM> experience the compression loading.

With reference to <FIG>, the weight sensing system <NUM> further includes a weight monitor <NUM> and, in some cases, one or more spot-check sensors <NUM> (see <FIG> and <FIG>). The weight monitor <NUM> may include or be provided as a computing device (fixed or portable) and includes a processing unit <NUM>, a memory unit <NUM> and an input/output (I/O) unit <NUM> by which the processing unit <NUM> is communicative with the weight sensors <NUM> and, where applicable, the one or more spot-check sensors <NUM>. The memory unit <NUM> has executable instructions stored thereon, which are readable and executable by the processing unit <NUM>. When the executable instructions are read and executed by the processing unit <NUM>, the executable instructions cause the processing unit <NUM> to operate as described herein.

When the executable instructions are read and executed by the processing unit <NUM>, the executable instructions may cause the processing unit <NUM> to periodically request and receive data that is reflective of the portions of the entire weight of the hood body <NUM> over time that is supported by each support leg <NUM> from each of the weight sensors <NUM> and to calculate the entire weight of the hood body <NUM> over time from this data. In addition, when the executable instructions are read and executed by the processing unit <NUM>, the executable instructions may further cause the processing unit <NUM> to interpret the data so as to monitor changes in the entire weight of the hood body <NUM> over time and to take an action toward cleaning the hood body <NUM> in an event the changes indicate that the entire weight of the hood body <NUM> exceeds a predefined level.

In accordance with embodiments, the predefined level may be set as a weight of the hood body <NUM> which is historically indicative of a dirty condition. The predefined level may be manually or automatically adjustable over time.

In accordance with embodiments and as shown in <FIG>, the one of more spot-check sensors <NUM> may be operable by the processing unit <NUM> in accordance with the executable instructions and configured to execute spot-checks of the hood body <NUM>. The spot-check sensors <NUM> may be optical sensors or any other suitable type of sensor <NUM> that can be employed to inspect various components or locations of the hood body <NUM> for certain conditions, such as grease build-up. Here, the weight monitor <NUM> may be further configured to take the action toward cleaning the hood body <NUM> in an event the operations of the one or more spot-check sensors <NUM> indicate that the action should be taken irrespective of the changes indicating that the entire weight of the hood body <NUM> exceeds the predefined level. That is, in an event the spot-check sensors <NUM> find a dirty condition that needs to be cleaned even when the hood body <NUM> is not overweight, such as when the screen <NUM> is dirty but the duct sidewalls <NUM> are not yet dirty, the weight monitor <NUM> can take the action toward cleaning at least the screen <NUM>.

With reference to <FIG>, a method of monitoring a cleanliness of the hood body <NUM> of the ventilation hood system <NUM> as described above is provided. As shown in <FIG>, the method includes installing the weight sensors <NUM> at the support legs <NUM> of the hood body <NUM> (block <NUM>), sensing, at each weight sensor <NUM>, a portion of an entire weight of the hood body <NUM> which is supported by the corresponding support leg <NUM> (block <NUM>) and generating data reflective of the entire weight of the hood body <NUM> over time from results of the sensing of block <NUM> (block <NUM>). The method may further include interpreting the data to monitor changes in the entire weight of the hood body <NUM> over time (block <NUM>) and taking an action toward cleaning the hood body <NUM> in an event the changes indicate that the entire weight of the hood body <NUM> exceeds the predefined level (block <NUM>).

In accordance with embodiments, the interpreting of the data of block <NUM> may include comparing the data with baseline or prior data and the taking of the action of block <NUM> may include scheduling the cleaning irrespective of a cleaning schedule. Also, the method may further include executing spot-checks of the hood body <NUM> (block <NUM>) and taking the action toward cleaning the hood body <NUM> in an event the executing of the spot-checks indicates that the action should be taken irrespective of the changes indicating that the entire weight of the hood body <NUM> exceeds the predefined level (block <NUM>).

Claim 1:
A ventilation hood system (<NUM>) comprising:
a hood body (<NUM>) defining an interior (<NUM>) through which cooking vapors are passable, the hood body (<NUM>) comprising duct sidewalls (<NUM>) enclosing the interior (<NUM>), a screen (<NUM>) through which the cooking vapors are passable, and a fan element or blower that is installed in or adjacent to the interior, the screen (<NUM>) being disposed in the interior (<NUM>) and supported by the duct sidewalls (<NUM>);
a support system (<NUM>) affixed to a fixed body (<NUM>) and supportive of an entire weight of the hood body (<NUM>), the support system comprising one or more support legs (<NUM>) each respectively comprising a bracket (<NUM>); and
a weight sensing system (<NUM>) including weight sensors (<NUM>) respectively disposed in the corresponding brackets (<NUM>) and a weight monitor (<NUM>), wherein the weight monitor (<NUM>) comprises a processing unit (<NUM>) and the weight sensing system (<NUM>) is operably coupled to the support system (<NUM>) to sense and monitor the entire weight of the hood body (<NUM>) over time,
wherein the weight monitor (<NUM>) is configured to: receive data reflective of the entire weight of the hood body (<NUM>) over time, interpret the data to monitor changes in the entire weight of the hood body (<NUM>) over time, and take an action toward cleaning the hood body in an event the changes indicate that the entire weight of the hood body (<NUM>) exceeds a predefined level.