Abstract: An aural or visual alarm is arranged to be actuated upon leaving a door to an appliance open longer than a preselected period of time. An automatically resettable disarming device may be included to permit leaving the door open intentionally for an extended time to permit appliance cleaning or the like.

Abstract: A remote temperature sensing and warning system for a temperature controlled vehicle comprising a remote temperature sensing unit for measuring the temperature in the transport container and transmitting the temperature signal within a repeating time frame through the existing vehicle wiring to a remote receiver; the receiver decoding and converting the signal into a displayable form to continuously display the current temperature of the transport container; the receiver further detecting out of range temperatures and signal transmission errors and providing visual and aural alarms therefrom.

Abstract: A temperature controller and method of controlling temperature for use in a refrigerating device includes a temperature sensor for detecting temperature in a compartment of the refrigerator, a conversion element, a refrigerating cycle driving element, a comparison element, and a memory element. The conversion element converts the temperature detected by the temperature sensor into a voltage value. The refrigerating cycle driving element operates a refrigerating cycle to cool the compartment in accordance with the voltage value. The comparison element compares the voltage value with a predetermined voltage range. This predetermined voltage range is wider than a voltage range corresponding to an ordinary operating temperature range at which the temperature in the compartment is maintained.

Abstract: An alarm apparatus is provided for a freezer having a body and a closure member. The alarm apparatus has an electrical control unit having a power supply input. An alarm device and a temperature sensor are connected to the control unit. The temperature sensor is adapted for mounting in the freezer, for detecting temperatures exceeding a pre-set temperature. A flexible lead is provided for connecting at least two of the control unit, the alarm device and the temperature sensor together. The lead has a cross-section enabling it to extend between the lid and the body of a freezer, while permitting closure thereof. The alarm apparatus can include a second lead connecting the alarm device to the control unit, to enable the alarm device to be placed at a location remote from the freezer.

Abstract: An electronic monitoring system for a refrigerated unit has sensing means responsive to temperature within the unit, conditions of the engine driving a compressor, security controls of the unit, all interconnected with solid state programming means in order to provide visual, audio, and transponding alarms in the event of a malfunction within the unit.

Abstract: A temperature controller and method of controlling a refrigerating device includes a temperature sensor for detecting temperature, a conversion circuit, a refrigerating cycle driving circuit, a comparison circuit, a failure decision circuit, and a memory circuit. The conversion circuit converts the temperature detected by the temperature sensor into a voltage value. The refrigerating cycle driving circuit operates a refrigerating cycle to cool a compartment in accordance with the voltage value. The comparison circuit compares the voltage value with a reference voltage range. The reference voltage range is changed by the failure decision circuit to two different states. The reference voltage range in the first state includes an ordinary voltage range corresponding to an ordinary operating temperature range of the refrigerating device. The reference voltage range in the second state includes the first state reference voltage range.

Abstract: The status corresponding to the presence or absence of articles at their reserved locations is detected by means of an optical switch comprising an emitter which sends infra-red rays toward a receiver. The article obstructs these rays and hence its presence is detected. The information obtained from the optical switches is processed and used for servicing or billing.

Abstract: An alarm for a milk cooler which sounds when the temperature of milk within the cooler exceeds a predetermined value. A switch permits the device to be turned off to prevent it from sounding when milk is being discharged from the cooler or when the cooler is being cleaned with hot cleaning solvent. However when fresh milk is being introduced into the cooler that switch is overridden and the alarm sounds should the milk not be cooled to the required temperature after a predetermined interval of time.

Abstract: An alarm is disclosed herein for providing an indication when a certain condition, such as a door ajar condition of a refrigerator, has existed for a predetermined time. The alarm includes a capacitor, means coupled to the capacitor for charging same while the certain condition is in existence, an indicating device and a voltage sensitive switch coupled to the capacitor and to the indicating device for repetitively partially discharging the capacitor through the indicating device when the charge on the capacitor reaches a particular level. A series of alarm pulses are thereby developed by the indicating device once the certain condition has existed for the predetermined time whereby the alarm pulses are separated by equal intervals substantially shorter than the predetermined time. The alarm of the instant invention is simple in construction and inexpensive.

Abstract: A device for indicating that a refrigerator door is open, includes a housing which is mountable on a refrigerator in the vicinity of the refrigerator door during the use of the device. A transducer is mountable at the refrigerator door gasket for changing an electrical parameter in response to the movement of the refrigerator door from its closed position to an open position. Circuitry disposed in the housing senses the change in the electrical parameter of the transducer to produce an alarm after a preselected time delay.

Abstract: An electrically operated thermometer for a cold storage room is normally supplied with current from the secondary winding of a transformer, the primary winding being connected to a conventional alternating current source. A battery is alternatively connected to the thermometer through a manual switch, which is preferably of the momentary type, which must be held engaged.

Abstract: Monitoring apparatus for sensing the temperature within a refrigeration unit that experiences periodic defrosting cycles. The apparatus is capable of discerning the differences between a normal defrost cycle and system failure and provides a warning signal when a failure occurs.

Abstract: A door ajar alarm system for a refrigerator-freezer, the system having a variable alarm delay period. The door ajar alarm system includes a control which may be digital or analog for monitoring various operating conditions of the refrigerator such as the temperatures of the refrigerator compartments and whether the refrigerator is undergoing a defrost operation. The control determines the alarm delay period in accordance with the monitored conditions such that the delay period is decreased in response to each monitored condition which reaches a predetermined status. The door ajar alarm thus alerts the user to operating conditions which are likely to produce an undesirable temperature within the refrigerator more rapidly than usual or to produce temperatures from which recovery is unusually slow.

Abstract: A device simply and effectively senses undesirably high temperatures in a refrigerated volume with an accuracy of about 3 percent, and activates an indicator in response to the sensing. A temperature probe is disposed in a freezer, refrigerator, or cooler volume, the probe including a negative temperature coefficient thermistor forming part of a voltage measurement bridge. The resistors of the voltage measurement bridge are all accurate to one percent, and are connected up to a voltage comparator of an integrated circuit. A 9 volt battery powers the device. The device also includes a low battery voltage sensor for activating the indicator when the battery voltage drops below about 8.2 volts, and a sensor for detecting when the probe is damaged or disconnected. The probe detection circuit includes a Darlington transistor, and resistor, the Darlington transistor being connected through a diode to the indicator. The indicator may include a piezo electric horn driven by a horn oscillator circuit.

Abstract: A door-open alarm device comprises alarm means connected to an electric circuit which comprises, arranged on the stationary part (11), a voltage source, a switch (13) having two positions in which the circuit is interrupted and closed respectively, electrical time delay means responsive to a current flow in the circuit to produce a voltage variation across said alarm means after a time delay, thereby triggering said alarm means. Arranged on the door (12) is a mechanical actuating element (14) for said switch, which opens said switch when the door is wide open or closed, and which closes said switch when the door is ajar.

Abstract: A device for detecting leaks of cryogenic materials from a structure, said device comprising a heat-conductive element which can be brought into contact with the cryogenic material-containing structure, and a shape memory effect element capable of effecting a displacement according to the cryogenic temperature to which the element is subjected.

Abstract: A refrigeration monitor system for monitoring an unattended freezer installation having a number of freezer compartments containing perishable products. The system comprises a network of temperature sensors located in the freezer compartments and connected to a common control which is connected to one or more telephone lines. The common control is capable of dialling in sequence anyone of a group of selected alarm numbers. The person answering the alarm call receives a recorded message and must return a preselected answer code that is received by the system, and which stops the system from sending more alarm calls. The system continues to dial alarm numbers until it receives a satisfactory answer code. As a further safety measure the system, upon initiating an alarm, sets an alarm status indicator that must be manually reset within a preset time by the person attending to the freezer installation in response to the alarm, or else a new alarm sequence is automatically initiated.

Abstract: A microcomputer based monitor and display system for a refrigerator in which visual indicia are provided to indicate to the user the degree of door usage on a rolling average time basis. Threshold time limits are established to correspond to heavy, normal and light usage. The actual door-open time is sensed and accumulated in successive time segments. The rolling average door open time over a predetermined number of time segments is calculated at the end of each time segment and the appropriate lamp is lit depending on how the calculated average door-open time compares to the established threshold values.

Abstract: A diagnostic system for identifying certain disabling abnormal conditions in an ice maker. The system includes a display panel having a pair of indicator lights and a push button switch, which when used together with a legend enables the operator to determine which particular abnormal condition needs correction.

Abstract: A temperature sensing means for a refrigeration apparatus including sensing means responsive to the temperature within a refrigerated space and to an ambient temperature condition for signalling the temperature condition of the refrigeration apparatus. In the disclosed embodiment, the sensing means is mounted in the access door of the refrigeration apparatus and the temperature sensors are mounted within a single housing. The sensor for sensing the ambient temperature is effectively insulated from the refrigerated space and senses the ambient temperature through a portion of the housing and door. In the illustrated embodiment, the sensing means is used to provide an ambient temperature compensated over-temperature alarm for the refrigeration apparatus.

Abstract: An alarm system for sensing temperature in a refrigerated truck trailer and for providing warning when trailer temperature exceeds one of a plurality of selectable monitor temperatures. The system includes a sensor bank adapted to be positioned within the refrigerated compartment being monitored. A control module, preferably positioned within the truck cab in proximity to the owner or driver, is electrically interconnected therewith. The control module is adapted to be switched between test, off and alarm modes. In the test mode a visual and audio indicator provides a test warning. In the alarm mode the circuit will warn the driver when the temperature within the refrigerated compartment exceeds the target temperature selected by a temperature select switch. To initiate operation of the alarm system, a set indicator provides a constant warning until the remote sensor units cool below their trigger point.

Abstract: A pair of electrical conductors is positioned in an elongated flexible insulating member and enclosed in an elongated tubular member filled with water or an aqueous solution having a known freezing temperature, the tubular member being sealed at its ends with the electrical conductors in their insulating member extending outwardly of one of the sealed ends and connected with an alarm actuating circuit. A portion of the insulating member is removed from one of the pair of electrical conductors adjacent one end of the same within the tubular member and a portion of the insulating member is removed from the other one of the pair of electrical conductors adjacent the opposite end thereof so that an electrical circuit is completed through the water or aqueous solution in the elongated tubular member and interrupted when the water or aqueous solution freezes.

Abstract: A freezer alarm sensor has a body in which there is an elongated vertically extending chamber. Contactors connectable in an alarm energizing circuit, normally insulated from one another, are exposed in the chamber, near one of its ends and diametrically opposite one another. A current conducting slider is freely slidable in the chamber between a raised position spaced from the contactors and a dropped position engaging the contactors and electrically connecting them. The chamber is partially filled with material that is solid at temperatures below a predetermined value and by which the slider is bound to the body and thus held in its raised position, but said material melts at temperatures above that value, releasing the slider to fall to its dropped position. Also disclosed are a heat sensor and a flood sensor embodying principles of the invention.

Abstract: An electrical outlet is connected in a parallel circuit to the compressor unit of a standard household refrigerator. A lamp can be connected to the outlet and will thus provide random lighting in the house in accordance with the on-off cycle of the refrigerator refrigeration unit thus giving the appearance that there is activity within the house to discourage burglars or the like.

Abstract: A plurality of detector units are positioned to sense the refrigerated air temperature of a refrigerated air supply to a retail frozen food case or counter. The detector units are battery powered and supply a modulated radio frequency output reflecting the existence of a temperature condition integrated over time together with identification codes identifying a particular detector unit. A receiver unit receives the transmitted radio frequency signal, demodulates and decodes the signal, and supplies an output to an alarm unit. The alarm unit develops the alarm signal and supplies it to an indicator, as well as to an external alarm circuit which is a phone dialer which automatically dials a phone number in an external telephone system. In addition, the detector unit periodically generates an operational check signal which is also transmitted to and decoded by the receiver unit and supplied to the alarm unit. The alarm unit indicates the existence of the operational check signal.

Abstract: A refrigerant compressor for use with an air conditioner for vehicles, which comprises a housing in which a vane pump is accommodated, and a covering disposed so as to enclose said housing in a fashion that its inner wall cooperates with the outer wall of said housing to define a refrigerant delivery chamber, characterized by that a temperature sensor is embedded in a portion of the outer wall of said housing. The sensor may be composed of a semiconductor thermo-sensitive device or a conductor wire made of a metal including a high resistance metal. Thus, accurate and stable detection of the internal temperature of the compressor is feasible, thereby making it possible to avoid seizure of the sliding machine parts of the compressor.

Abstract: A housing enclosing a control for use in an electrical apparatus having structure defining a control space arranged to preclude access to the control in the housing when the housing is in the control space. The apparatus may include a connecting device for connecting the apparatus to an alternating current power supply for normal electrical operation of the apparatus. The control may comprise an alarm device which causes operation of the alarm upon a malfunctioning of the apparatus, and includes a battery for operating the alarm in the event of a failure of the power supply. The battery is removably connected to a circuit board portion of the control and a structural portion of the electrical apparatus prevents replacement of the battery and exposure of the control circuit when the housed control is in the control space and connected to the alternating current power source.

Abstract: An alarm signal device sounded by a self-contained power source is activated responsive to a variance of temperature within a refrigerator or freezer beyond set limits. A timing circuit in the form of an integrated circuit causes the alarm to sound or flash intermittently for periods of extremely short duration compared to the relatively long periods between warning signals, thus extending the life of the alarm power source.

Abstract: A device having a single elongated non-metallic sealed container provided with electrical contacts is connected by appropriate electrical wiring to an alarm device. The electrical contacts are in a circuit with a displaceable electrically conductive member which may bridge the contacts for completing the circuit to the alarm device. A re-useable congealable material is contained within the sealed container, the congealable material having a predetermined low congealation temperature for maintaining the electrically-conductive member above the contacts as long as the device is at the suitable low temperature. On subjection of the sealed container to a sufficiently high temperature for a sufficient period of time, the congealable material takes on a liquid state and the electrically-conductive member is allowed to fall toward and bridge the contacts, thereby permitting electrical closure of the contacts when an undesirable temperature condition is present within the freezer compartment.