Battery water level detector for a battery operated device

A battery water level detector assembly for a battery operated device comprising a control unit configured for use with a battery of the device, with the control unit including an electronic sensor operative to provide a signal indicative of the water level within the battery and with the control unit being operative to provide a control signal in response thereto. The electronic sensor is operative to detect when a visual indicator operably connected to the battery provides a display that the water level within the battery has decreased below a desired level. The control signal in turn may be used to generate an alert, including a remotely transmitted alert, and/or alter operational functionality of the battery operated device.

BACKGROUND OF THE INVENTION

The present invention is directed to a device, system and method for detecting the water level in a battery operated device, and in particular for providing an alert and/or controlling operation of the device.

Numerous types of equipment or devices operate utilizing rechargeable lead-acid batteries, such as floor scrubbers, carpet extractors, floor burnishers, vacuums, golf carts, forklift trucks, automated guided vehicles, electric transportation carts, such as people movers used in airports, utility carts, man lifts, tuggers, and the like. The batteries of such devices require water because the water off gasses during use of the battery. Accordingly, intermittent maintenance to the batteries is required to replenish the water as needed based on use of the device and batteries. It is important in such batteries that the proper water level be maintained in order to prevent damage to the battery that otherwise can occur when the batteries are used with low water levels.

SUMMARY OF THE INVENTION

The present invention provides a battery water level detector for a battery operated device, and a method of detecting water level within a battery and providing a signal in response thereto to provide a warning and/or control operation of the device.

According to an aspect of the present invention, a battery water level detector comprises a control unit mountable to a battery, with the control unit including an electronic sensor. The electronic sensor is operative to provide a signal indicative of the water level within the battery, with the control unit in turn being operative to provide a control signal in response thereto. In particular embodiments the electronic sensor detects when a visual indicator on the battery provides a display that the water level within the battery has decreased below a predetermined level. The detector assembly may further include a cap assembly that is mountable to the battery within one or more holes provided on the battery by the manufacturer, where the cap assembly includes the visual indicator for providing a display that the water level within the battery has decreased below a predetermined level.

According to a further aspect of the present invention, a battery operated device is provided that employs a battery water detector assembly, where the output signals from the detector assembly control sensory signals and/or operational parameters of the battery operated device. In particular embodiments the battery operated device includes an alert mechanism that is operative to provide a visible warning light, an audible sound, or a tactile warning when the controller provides a control signal in response to detection of a low battery water level. Alternatively or additionally, the control signal output by the controller is operative to alter the battery powered operational functionality of the battery powered device in response to detection of a low battery water level condition.

According to an aspect of the present invention, a floor scrubber includes a battery water level detector assembly comprising a controller and an electronic sensor, with the floor scrubber further comprising a battery, a scrubber head, and a scrubber head motor for operating the scrubber head, with the scrubber head motor being powered by the battery and with the battery including a battery opening. The electronic sensor is operative to provide a signal to the controller indicative of the water level within the battery with the controller being operative to provide control signals in response thereto to control operation of the floor scrubber. In particular embodiments, the controller provides a control signal to prevent the scrubber head motor from operating upon detection that the water level within the battery is below a predetermined limit and/or the floor scrubber further includes an indicator light with the controller providing a control signal to illuminate the indicator light upon detection that the water level within the battery is below a predetermined limit. Still further, a drive motor for providing motive power to the floor scrubber may continue to operate even in the condition of a low battery water level in order to enable the floor scrubber to be returned to a storage or maintenance location.

The battery water level detector assembly includes an indicator extending into the battery through the battery opening and has a lower end and an upper end, with the lower end configured to contact internal water of the battery when the battery water level is at a desired height. The electronic sensor in turn provides a signal to the controller indicative of a low water level condition in response to the water level within the battery dropping below the lower end of the indicator. In a particular embodiment the indicator is an optical indicator and the electronic sensor comprises a light sensor, such as an infrared light sensor, aligned with the upper end of the indicator.

In still further embodiments, the battery water level detector assembly comprises a cap assembly mountable to the battery over the battery opening and a control unit that includes the electronic sensor and controller. The control unit may further comprise a separate housing that is mountable to the cap assembly.

The battery water level detector system of the present invention avoids the necessity of having an individual manually check the battery water level, and is operationally employed to provide alert signals regarding a low water level condition and/or control operation of the battery powered device without requiring additional holes or openings in the battery that could void battery warranties. In the case of a floor scrubber battery powered device, for example, refilling of the batteries is further ensured by preventing the scrubber head motor or motors from operating when a low level condition is detected. Thus, problems associated with drawing current from the batteries by operation of a battery powered device, such as a floor scrubber, when the water level is too low are thereby avoided.

These and other objects, advantages, purposes and features of this invention will become apparent upon review of the following specification in conjunction with the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will now be described with reference to the accompanying figures, wherein the numbered elements in the following written description correspond to like-numbered elements in the figures. A battery operated device, which in one embodiment comprises a floor scrubber30with a head32for cleaning floors is shown inFIG. 1, where floor scrubber30is an operator walk-behind type scrubber having a base assembly with forward wheels34and rear wheels36for supporting movement of scrubber30on a floor, as well as various tanks for providing cleaning fluid and suctioning and retaining used fluid from the floor. Floor scrubber30includes multiple batteries38retained within a battery compartment40, where batteries38are used to provide operational power to floor scrubber30. Batteries38, for example, are used for powering drive motors42for driving wheels34to assist in moving floor scrubber30, and for powering motor44of cleaning head32, as well as for providing power to the motor46used to create a vacuum in tank48and thereby suction fluid from the floor being cleaned.

Batteries38are conventional batteries that include multiple cells containing water for operation of batteries38. As shown inFIG. 2, batteries are provided with a battery water level detector assembly50(one shown inFIG. 2), which in the illustrated embodiment comprises a cap assembly or manifold assembly52and a control unit54. As discussed in detail below, assembly50is operable to detect when the water level within battery38has dropped below a desired, pre-set level. Assembly50then provides a warning or an alert to the operator of floor scrubber30, such as illuminating low level water light51alocated on a control panel53at the rear of floor scrubber30(FIG. 3). Assembly50also controls operation of floor scrubber30to limit or alter battery powered operational usage or functionality of scrubber30upon detection of a low level water condition to thereby inhibit damage to batteries38that may occur as a result of being used with a low water level. For example, to prevent operation of motor44whereby floor scrubber30is inoperable to clean floors until the water within batteries38is replenished to the required level. As discussed below, although the battery water level detector assembly50is shown in connection with a battery operated device comprising a floor scrubber30, it should be appreciated that battery water level detector assemblies in accordance with the present invention may be employed with numerous alternative battery operated devices.

Referring now toFIGS. 4 and 4A, assembly50is shown in relation to battery38. As shown, battery38includes three separate ports or openings60a,60b,60cthat are provided in battery38by the manufacturer of the battery38and into which water is selectively supplied for the internal cells of battery38. Cap assembly52is attachable to battery38and includes three filler tubes54a,54b,54cthat align with respective ones of the openings60a,60b,60cof battery38. Cap assembly52further includes a fluid fitting56to which water lines (not shown) are connected for supplying water into battery38through internal passages (not shown) leading to filler tubes54a,54b,54c.

Cap assembly52also includes a water level indicator, which in the embodiment shown comprises an optical indicator device58having a second or lower end60and a first or upper end62. When cap assembly52is affixed to battery38, indicator58extends into opening60bof battery38. As understood fromFIG. 4A, the underside or bottom55of cap52includes annular flanges57that mate with annular flanges59on battery38, where a seal ring may be disposed there between. Indicator58passes through cap52to extend past the bottom55internally of one of the flanges57to extend into battery38.

In operation, end60of indicator58will extend into and be in contact with the water within battery38when the water level within battery38is within the proper specified range. The length of indicator58is constructed such that when the water level within battery38decreases beyond a pre-set limit end60will no longer be in contact with the water. In the illustrated embodiment indicator58comprises or operates in the manner of a light pipe, with lower end60being conical whereby end62is able to provide an indication of when the water has decreased beyond a desired limit, such as based on the refraction of light. By way of explanation, when control unit54is not installed end62has a dark visual appearance when end60is submerged in water within battery38, and end62has a white visual appearance when the water level decreases below end60. Although cap assembly52is shown to include three filler tubes for use on a battery having three ports, it should be understood that alternative cap assemblies having more or fewer than three filler tubes may be employed for use with correspondingly constructed batteries.

In the illustrated embodiment, battery38and cap assembly52comprise a battery and cap assembly provided by the Trojan Battery Company of Santa Fe Springs, Calif., U.S.A., with the cap assembly being provided as part of the HYDROLINK watering system. It should be appreciated, however, that alternative cap assemblies may be readily employed.

Referring now toFIGS. 4-8, control unit54includes a housing64comprising a base66and lid68within which a controller or control module70is contained, such as a microprocessor contained within housing71, with controller70having wires or leads72that extend out of housing64and including fasteners74to hold lid68on base66to retain controller70within housing64. Leads72are used to provide power to controller70, as well as to enable various operations or controls to be provided to scrubber30by way of control signals provided by controller70. Base66includes a pair of integral downward projecting members or clips76,77with inwardly projecting latches78,79, respectively, for attaching or clipping housing64to the edge or lip80that projects outwardly from cap assembly52. It should be appreciated that controller70may be constructed of various circuitry components, such as may be mounted on a circuit board.

As shown inFIGS. 6-8, controller70includes an electronic sensor or optical sensor, which comprises a light sensor82in the illustrated embodiment that, when assembled into housing64, aligns with an opening84in the bottom86of base66. Housing64of control unit54is then affixed to cap assembly52with opening84being aligned with upper end62of indicator58and a seal ring85being positioned at opening84between base66and the top87of cap assembly52. In the illustrated embodiment sensor82is a reflective sensor that consists of an infrared emitting diode88mounted side-by-side to a photo detector or phototransistor90. In operation, sensor82is able to detect when the water level in battery38has decreased beyond the pre-set desired limit due to the change in reflectivity of lower end62of indicator58when the water level drops below lower end62of indicator58. That is, sensor82provides an output signal indicative of a low water level condition. The level of light detection by sensor82is then processed by controller70, with output signals being provided by controller70based thereon. Sensor82may be a QRD1113 or QRD1114 Reflective Object Sensor provided by Fairchild Semiconductor Corp. of San Jose, Calif., U.S.A.

As previously noted, upon detecting a low water level condition of battery, controller70operates to cause warning light51to be illuminated. In addition, leads72extend to control relays92, such as may be located adjacent control panel53(FIG. 1) where, upon detection of a low water level condition, relays92are tripped by a signal from controller70to stop the operation of head32, as well as prevent further discharge of cleaning fluid from the scrubber30. For example, in the case of a rotary scrubber head or an orbital scrubber head the motors for imparting movement to the cleaning pads are prevented from operating. Power may still be permitted to be supplied to the drive wheels and/or vacuum, however, to enable discharged water to be collected and to enable the operator to return the floor scrubber30to a storage or service location. Detector assembly50, therefore, prevents the floor scrubber30from being used to actually clean floors once the battery water level has decreased below a desired level, but may be configured to still enable an operator to transport the floor scrubber30to a location where it may be more readily serviced. Alternatively, instead of relays92, floor scrubber30may be provided with various types of conventional switches or an additional controller for receiving a signal from controller70and, in turn, altering operational functionality, such as limiting or preventing certain operations of floor scrubber30.

Upon re-filling batteries38with water to the required level, lower end62of indicator58will again be submerged, which will be detected by control unit54via operation of sensor82. Upon detection of a proper water level, control unit54will turn off warning light51and re-set relays92to allow continued operation of the scrubber head32.

The schematic operation of one embodiment of the battery water level detector assembly50is shown inFIG. 9. As there illustrated, sensor82provides an output indicative of the water level within a battery38, which signal is then processed by controller70to determine whether or not the water level within battery is appropriate. If the water level is determined to be appropriate, normal operation of the floor scrubber30is continued. If the water level is determined to be low, controller70outputs control signals94that may be used to cause a sensory alert or warning to be triggered, such as causing light51ato be illuminated, and/or trips relays92to prevent operation of scrubber head32.

Changes and modifications in the specifically described embodiments can be carried out without departing from the principles of the present invention which is intended to be limited only by the scope of the appended claims, as interpreted according to the principles of patent law including the doctrine of equivalents. For example,FIG. 2discloses a battery water level detector assembly50on one of the batteries38, with cap assemblies52on each of batteries38. It should be appreciated that assemblies50may be placed on each battery38by the inclusion of control units54on each of the cap assemblies52. In which case scrubber30may be configured to trigger light51aand trip relays92upon detection of a low level water condition in any one of the batteries.

As understood fromFIG. 9, output signals94from controller70may also be used to additionally or alternatively cause other types of sensory alerts or warnings to be triggered. For example, an audible alarm51b(FIG. 3) may be triggered, such as a beeping sound upon detection of a low water condition, or a tactile warning, such as a vibration of handle51c(FIG. 3) may be triggered via a vibratory motor. Still further a battery powered device may also be equipped with a transmitter to provide an indication of a low water level condition remote from the battery powered device. With regard to the floor scrubber30, for example, a transmitter96(FIG. 1) is provided that receives an output control signal94from controller70, and in turn transmitter96sends an alert signal to provide a remote alert regarding the low water level condition. Various types and forms of transmitters96may be employed for providing various types of alert messages. For example, alerts such as a text message or email may be sent by transmitter96, such as are viewable on a smart phone or other type of computing device.

Although shown in connection with a floor scrubber30, it should be appreciated that battery water level detector assemblies in accordance with the present invention may be employed with alternative battery operated devices as well. Other such battery operated devices may include golf carts, forklift trucks, automated guided vehicles, electric transportation carts, such as people movers used in airports, utility carts, man lifts, tuggers, and the like. It should further be appreciated that the battery water level detector assembly may also be used with non-mobile battery operated devices.

Still further, control signals94may also be used to effect the operation of alternative or additional control parameters of a battery powered device, or provide further enhancements. Although discussed above in regard to preventing operation of motor44of floor scrubber30, a control signal may be used to alter functionality of a battery powered device, such as to prevent or limit numerous other types of operations of a battery powered device. For example, a vacuum and/or a pump motor may be shut off or prevented from operating until the battery water level is again within specification, or if so equipped, a burnisher motor may be prevented from operation. Still further, the transport speed of a battery powered device may be limited. The lifting operation, such as for the forks of a forklift or the head of a floor scrubber could be prevented, such as preventing forks from lifting or the head of a floor scrubber from lowering. It should be understood that numerous different limitations or enhancements to the operation of battery powered devices may be employed to both prevent damage to the batteries, and provide an impetus for replenishing the battery water.

Battery water level detector assembly50is discussed above in regard to the use of a cap assembly52and an electronic sensor82configured as a reflective sensor. However, in alternative embodiments, battery water level detector assembly50does not require cap assembly52and/or may be used with alternative types of electronic sensors and alternative physical configuration. For example, one or more of batteries38may be provided with one or more unitary cap assemblies or plugs, each of which fit directly into one of the holes provided on a battery, such as one of holes60a,60b,60cprovided on battery38. Various examples of such alternative cap assemblies are shown inFIGS. 10-12, where various such cap assemblies may be provided by Flow-Rite Controls of Byron Center, Mich.

As shown inFIG. 10, cap assembly152includes an optical indicator158that is substantially similar to optical indicator58discussed above, with indicator158including a lower end160and an upper end162. As with indicator58, lower end160contacts water in a battery when the water level is within the desired range, with upper end162displaying a dark visual appearance when end160is submerged in water within the battery38, and end162having a white visual appearance when the water level decreases below end160. Cap assembly152, however, includes a sleeve portion100and a shoulder102, where sleeve portion100is configured to be inserted into an opening on a battery, such as one of holes60a,60b,60cprovided on battery38, with shoulder102then contacting flange59disposed about the respective hole60on battery38. When used with cap assembly152, a control unit may be constructed to align electronic sensor82with upper end162by affixing the control unit to the battery.

FIG. 11illustrates an alternative cap assembly252that includes a sleeve portion200, a shaft204, upper end206and lower end208. Sleeve portion200is configured for insertion into a manufacturer provided hole on a battery, with lower end208contacting water within the battery when the water level is within specification and lower end208not contacting water within the battery when the water level decreases beyond a desired level. As understood fromFIGS. 11A and 11B, upper end206provides an alternative visual indication of the water level relative to cap assembly152. Upper end206includes a lens through which the water within the battery can be viewed with a pattern being visible through the lens, which in the illustrated embodiment comprises a striation pattern. As understood fromFIG. 11A, when the water level is within specification and contacting lower end208, the striation pattern is shown to be distorted, such as may be caused by surface tension of the water contacting the lower end208. And as understood fromFIG. 11B, when the water level is below lower end208and therefore out of specification the striation pattern is not distorted. A control unit may therefore be provided with an alternative electronic optical sensor for operatively aligning with upper end206for detecting the change in the pattern, whereupon the appropriate output control signals may be provided.

Referring now toFIG. 12still another cap assembly352is disclosed which also includes a sleeve portion300for inserting into a single hole provided by a manufacturer on a battery, with cap assembly352operating in the manner of a mechanical float device. Cap assembly352further includes a shoulder portion302, a float member310with a bulbous lower float end312and an upper end314, where the upper end314of float member310moves within an optical scale member316that includes upper and lower gradations318,320. As water within the battery decreases, upper end314moves downward within member316, and once upper end314is level with lower gradation320the battery is required to be replenished. Accordingly, a control unit may be provided with an electronic optical sensor for operatively detecting this position to thereby provide an appropriate output control signal.

The battery water level detector assembly is thus operative to detect a visual indication of a low battery water condition, with the detector assembly then providing output control signals to trigger a sensory alert, such as an audible sound or visual light, and/or limit operational parameters of the device or provide enhancements for providing an impetus to replenish the water within the batteries. The various cap assemblies discussed above thereby operate as visual indicators, with the electronic sensor of the battery water level detector detecting the indication of a low water condition.