Patent Publication Number: US-10768053-B2

Title: Telescopic thermometer

Description:
RELATED PATENT APPLICATIONS 
     This patent application claims priority from U.S. Provisional Application 62/551,797 filed Aug. 30, 2017 and U.S. Provisional Application 62/62,182 filed Feb. 5, 2018. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to temperature measuring devices, and in particular, to temperature measuring devices for maintenance and repair of air conditioning units. 
     BACKGROUND OF THE INVENTION 
     Conventional hand-held thermometers may facilitate measuring the temperature but are not very accurate in measuring the temperature of the surfaces or of the air flows. Also, the conventional hand-held thermometers are not effective in measuring temperature the temperature of remote places as the distance between the thermometer and the place of interest can cause errors in the reading. This a significant problem for HVAC (Heating, Ventilation and Air Conditioning) devices. 
     There are two types of thermometers that are most commonly used in the HVAC field for measuring the temperature in an operating forced air unit. A first type is the electronic probe thermometer, more commonly recognized as a meat thermometer. This type of thermometer has a rigid pointy probe (metal probe) that one, in cooking applications, would stick into the center of a cooked roast. The electronic probe thermometer works by generating a small current across the electrodes of the metal probe, measuring how much current flows through the probe and thus the electrical resistance across the probe. Inside the thermometer, a microchip is used to convert this resistance into a temperature measurement that is displayed on the screen of the thermometer. The screen is provided on the opposite side of the probe, in front of the user, for enabling the user to see and record the temperature. This type of thermometer is also used in the HVAC field, and it comes in different shapes of housing. The electronic probe thermometer is without a doubt the most accurate thermometer and the most trusted for accuracy by a HVAC technician for many years. 
     However, all versions of electronic thermometers in the HVAC field use the same rigid straw-like metal probe with a pointy end to obtain air temperatures. 
     A disadvantage of using an electronic probe thermometer for obtaining air temperatures for HVACs is when a HVAC technician is seeking air temperature in a conditioned space. In this case, in most settings (90%), the technician needs a ladder because the metal air vent register that conditioned air is blowing out of, is in many cases over 10 feet above the floor. Therefore, in this scenario a technician would walk into a home, set up a ladder, climb the ladder to get within arm&#39;s length of the of an air supply grill to measure the temperature. He/she would then pull out a probe thermometer and insert the rigid probe inside, or very near, the air vent register so that the stream of conditioned air passes over the probe triggering the display unit to show the temperature on the screen. However, the correct temperature of the air is not provided immediately; it can take a few minutes for the probe thermometer to read the true temperature of the air. The main factor for the time delay is that the thermometer has been stored in a tool bag that has been sitting in a hot environment outdoors therefore heating up the probe of the thermometer. So, when being used to measure cold air, the cold air stream must first cool down the hot probe then bring it down to conditioned air temp. The hotter the probe, the longer the wait for accurate air temperature blowing from the air vent. Because of this, an HVAC technician might have his arms up holding the probe in a fixed position on a ladder for up to 4 minutes. This can be very tiering and frustrating for the technician. 
     To reduce the strain of the art held-out for such a long time, some technicians use a piece of duct tape and tape the thermometer to the air vent with the probe inside the grill to catch the air temperature, freeing the arms from holding the thermometer. This allows the technician to save time and perform other tasks as for example to check the refrigerant level or change the filter while the thermometer is taking time to record accurate air temperature. After the technician has recorded the air temperature coming from the air vent and the thermometer is no longer needed, the technician must climb back up the ladder, remove the tape and detach the probe thermometer from the air vent. 
     To summarize, the probe thermometer is the most accurate device in use today, but it requires the use of a ladder or the like for obtaining air temperature from air vents which is inconvenient and time consuming. 
     A second type of thermometer is a hand-held infrared laser thermometer which does not require the use of a ladder when seeking air temp from elevated air vents in the ceiling. With the infrared laser thermometer, a technician can be at ground level and shoot an infrared laser beam at the surface of the air vent and get near accurate air temperature. This measurement is displayed on a digital screen that is located on the hand-held device. This thermometer is convenient because no ladder is needed and it can provide temperatures on air vents that are hard to access even with a ladder because of obstructions like furniture or shelves. 
     However, it is well recognized that these infrared devices display wrong temperature readings; the readings may be so far off the technician knows there is a malfunction. The cause of errors in infrared thermometers include the reflection of radiation from a hotter body rather than radiated by the object measured. Sometimes, especially near ambient temperatures, the readings may be subject to error due to the body of the person holding the instrument. Also, the infrared thermometers do not capture the temperature of the air itself but only of the surface of the grill near the flowing air. For example, a user can take a temperature reading from 8 feet and get a reading of 105° F. At this distance, the user can feel the air from the air vent blowing and assume the reading will be between 75° F. and 80° F., to immediately realize that the reading is wrong. 
     Moreover, infrared laser thermometers are expensive since they employ infrared technology. In addition, conventionally, the measured temperature readings are temporarily stored in the memory of the thermometer and are then recorded manually by the user. Manually recording the temperature is prone to human errors. Also, the recorded temperature readings are prone to loss since the readings are stored temporarily. Conventionally, there are no ways of extracting the temperature reading from the telescopic thermometer. 
     To summarize, the infrared thermometer is convenient because no ladder or the like is required to obtain near accurate air temperature readings from an air vent, but it is an unreliable source if an exact air temp is desired by a technician. 
     Considering the pros and cons of both the probe type and the infrared laser type thermometers, there is need to have a thermometer that would give an accurate air temperature reading like a probe thermometer and at the same time be able to reach air vents and read air temperature of air vents or inside the air vents that are out of reach, without the use of a ladder like a infrared thermometer. 
     It is extremely important to use accurate air temperature readings in the formula for calibrating the operation of an AC system, called target super heat and sub cooling formula, to obtain a system running at maximum efficiency. Another important formula that requires accurate air temperature measurements is called the “temperature split” which is uses the difference in temperature between the return and supply air temperatures. Temperature split formula is used in almost every service call in the HVAC industry. 
     Also, there is a need to enable proper record keeping for the temperature readings, in order to enable comprehensive maintenance and repair for HVAC devices. 
     It is to be noted that while the specification describes the preferred embodiments with reference to the HVAC field, the telescopic thermometer presented here may be used in any other field of activity where remote measurements are necessary. 
     SUMMARY OF THE INVENTION 
     It is an object of this specification to provide a telescopic thermometer that allows a user to measure the temperature in places that are difficult to access. The telescopic thermometer described in this specification includes a telescopic body having a temperature sensing unit attached at an end of the body for reaching the place of interest for temperature readings. The device is enabled to measure the temperature on the surfaces of objects (appliances) or the air temperature, as needed. 
     Another object of the embodiments described in this specification is to provide a device that can be temporarily attached at a place of interest and released at will. In this way, the device can take a plurality of measurements while the user can perform other operations, related or unrelated to the temperature measurements. 
     Still another object of the embodiments described in this specification is to provide the telescopic thermometer with a display unit provided with a screen and a memory. The memory enables the user to store the temperature readings, alleviating the need for manually recording the temperature readings. The screen enables the user to readily see the temperature readings obtained with the temperature sensor placed at the remote location. The display unit may be enabled with a wireless transmitter to transmit the temperature readings to a networked device such as e.g. a smartphone, or laptop, or the like, over a wireless network. The display unit can also be provided with a microprocessor or a microchip for performing some basic processing of the temperature readings. 
     Accordingly, this patent specification presents a thermometer system for measuring temperatures, comprising: a telescopic body with a remote end that is adapted to be magnetically attached to a metallic air vent, and a gripping end that is adapted to accept forces that enable positioning of the remote end near the vent; a temperature sensing unit attached to the sensing end, and adapted to collect temperature measurements at the vent; and, a display unit attached to the gripping end and communicatively connected to the temperature sensing unit, the display unit arranged to enable viewing of the temperature measurements received from the temperature sensing unit, wherein the magnetic force of the remote end is strong enough to enable the thermometer system to remain attached to the vent event without any force being applied at the gripping end, after the magnetic sense becomes magnetically attached to the vent. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The drawings accompanying and forming part of this specification are included to depict certain aspects of embodiments of the invention. A clearer impression of embodiments of the invention, and of the components and operation of systems provided with embodiments of the invention, will become more readily apparent by referring to the exemplary, and therefore non-limiting, embodiments illustrated in the drawings, wherein identical reference numerals designate the same components. Note that the features illustrated in the drawings are not necessarily drawn to scale. 
         FIG. 1  illustrates an example of a system for temperature measuring using a telescopic thermometer. 
         FIG. 2  illustrates an embodiment of the telescopic thermometer. 
         FIG. 3A  shows a front view of another embodiment of the telescopic thermometer in an 180° setup. 
         FIG. 3B  shows a lateral view of the embodiment of  FIG. 3A , illustrating further details of the telescopic thermometer in a 90° setup. 
         FIGS. 4A and 4B  show the telescopic temperature device in operation. 
     
    
    
     DETAILED DESCRIPTION 
     The various features, details and advantages of the various telescopic thermometer are provided in this specification with reference to the non-limiting embodiments illustrated in the accompanying drawings. Descriptions of well-known starting materials, processing techniques, components and equipment are omitted so as not to unnecessarily obscure the disclosure in detail. Skilled artisans should understand, however, that the detailed description and the specific examples, while disclosing preferred embodiments, are given by way of illustration only and not by way of limitation. Various substitutions, modifications, additions or rearrangements within the scope of the underlying inventive concept(s) will become apparent to those skilled in the art after reading this disclosure. 
       FIG. 1  illustrates a system  100  using a telescopic thermometer  200 , for measuring the temperature of a plurality of appliances  102 - 1 ,  102 - 2 ,  102 - 3 , collectively referred to as the appliances  102 . In one example, the appliances  102  may be air conditioning units, room heaters, or the like. In the illustrated example, the appliances  102  are installed at a height above ground. As seen, the telescopic thermometer  200  has telescopic body  202  with a first end, also referred to as the remote end  202 - 1 , also referred to as remote end, and a second end, also referred to as the gripping end  202 - 2 . A temperature sensing unit  110  is provided at the at the remote end  202 - 1  and a display unit  120  is provided at the griping end  202 - 2 . 
     The temperature sensing unit  110  includes a sensor  204  (see  FIG. 2 ) of a modified probe type connected with the display unit through wires provided through the telescopic body. The sensor may be placed close or on the surface of interest for the temperature measurement by steering the telescopic body  202  from the gripping end  202 - 2 . This enables the user to measure temperatures of objects and places that are out of reach. Also, as seen later, the sensor  204  is provided at the end of a probe  220  that enables its positioning for a particular application. The remote end  202 - 1  is also provided with a releasable attachment  206  (see  FIG. 2 ) which enables the user to attach the telescopic thermometer to the appliance  102  and detach it at will. 
     The display unit  120  is provided with a digital display also referred as a screen  116 , a processor  112  with a memory (not shown) and a transmitting unit  114 . The screen  116  enables the user to see the temperature readings in real time, being placed in a position accessible to viewing by the user, preferably at on a bottom face  211  of the telescopic thermometer  200 . The processor  112  receives the measurement signal from the temperature sensing unit  110  as shown by arrow A and processes these measurements to a measurement data format appropriate for viewing on the screen  116 . As well, the processor  112  stores the measurement data in its internal memory for future viewing and/or local processing. Transmitter  114  receives the measurement data from the processor and provides it over wireless network  108  to a networked device  106 . Alternatively, the networked device  106  can be used to store the temperature reading recorded by the telescopic thermometer  200 . In this case, the networked device  106  may perform the processing of the recorded data, if/as needed. The networked device  106  could be for example a smartphone, a tablet, a PDA, a desktop, a laptop, or the like. For example, the wireless network  108  can be a Wi-Fi network, or Bluetooth or both. 
     It is to be noted that the data processing at the thermometer  200  can be minimal, involving only the display of the temperature readings. Alternatively, the display unit may be more complex and adapted to perform additional processing of the temperature readings that may be required for maintenance and repair of HVAC devices. Alternatively, a wired connection between the thermometer  200  and the device  106  may also be used. 
     During operation, when the temperature of the appliance surface is to be measured, the user operates the telescopic thermometer  104  to bring the sensor  204  (see  FIG. 2 ) of the temperature sensing unit  110  in contact with the appliance  102 . When air temperature is to be measured, the sensor  204  is placed in the space inside the vent, in the air passageway. One or more readings are performed, which are viewed and collected using the display unit  120 . 
     The structural details of one embodiment of the telescopic thermometer  200  and the manner the telescopic thermometer  200  operates are described with reference to  FIG. 2 . The telescopic thermometer  200  includes, as indicated above, a telescopic body  202  that has a variable length.  FIG. 2  also shows the remote end  202 - 1  of the telescopic body  202 , also referred as the first end, and the griping end  202 - 2 , also referred to as the second end. Sensor  204  of the temperature sensing unit  110  (see  FIG. 1 ) is placed at the end of probe  220 . 
     Telescopic thermometer  200  also includes a releasable attachment  206  adapted to releasably attach the thermometer  200  to an appliance or a nearby point of interest. Preferably, this may be a magnetic head  206  provided at the remote end  202 - 1 . Further, the telescopic thermometer  200  includes a thumb lock at the remote end  202 - 1  for controlling the releasable attachment  206 . In one example, once the user has placed the temperature sensor  204  at the place whose temperature is to be measured, the magnetic head  206  attaches the body  200  to the appliance  102  such that the sensor  204  assumes a desired position, which is a position in the air path exiting the vent in the example of  FIG. 2 , in this example. In one example, the magnetic head  206  can be made of a small earth magnet. For instance, the small earth magnet can be a rare earth magnet. Alternatively, the arrangement to releasably attach the thermometer may be a mechanical device, such as a clasp, hook or any type of removable, mechanical attachment. As indicated above, the use of the thermometer  200  is not limited to measuring air temperature; it could be used as well to measure the temperature on the surface of appliances of interest. If the temperature of a surface were to be measured, the sensor would be placed in contact with that surface. 
     In this example, to attain the place of interest in the air passageway, the probe  220  with the sensor  204  is arranged in a position suitable for the respective environment, which appliance in this example is the vent register  102 . Then, the user will simply extend the telescopic body  202  to a length allowing him/her to reach the vent register while standing on the ground/floor level and place the sensor  204  in the air passageway inside the vent register  102 . 
     The telescopic thermometer  200  may include a gripper  207  at the second end  202 - 2 , shaped to enable the user to firmly hold the telescopic body  202 . As well, the second end  202 - 2  may be provided with a housing  205  for the display unit  120 . As indicated above, the screen  116  is provided on the bottom face  221  of the housing  205 , to enable the user to see the temperature readings measured by the temperature sensor  204 in real time, from a position under the thermometer. In one example, the display unit is connected to the temperature sensor  204  by a wire that runs through the telescopic body  202 , as seen for example in  FIG. 3B . 
     During operation, the screen  116  receives the temperature readings from the temperature sensor  204  and displays the temperature readings to the user. In this setting, the wireless module  114  relays the temperature readings to the network device  106  for storing and processing, thereby eliminating the need of manually recording the temperature reading by the user. As indicated above, the display unit  120  may include a local memory for storing the temperature readings for future use (viewing or transmission, or both). 
       FIGS. 3A and 3B , collectively referred to as  FIG. 3 , show another embodiment of the telescopic thermometer, denoted with  300 . Similar to the embodiment of  FIG. 2 , telescopic thermometer  300  includes a telescopic body  302  with a first end  302 - 1  equipped with a temperature sensing unit, and a second end  302 - 2 , equipped with a display unit. 
     The temperature sensing unit in this embodiment includes an elongated, flexible temperature probe  320 , with a diode element (the sensor)  304  at the end of the probe. The flexible temperature probe  320  is preferably 3-4 inches long and completely flexible to all angles. As a comparison, the flexible temperature probe  320  is flexible like a piece of 12-gauge romex wire that can bend at a certain angle and then keeps its position. The actual material the flexible probe  320  is made of is a hollow stainless-steel flexible conduit. Two very thin gauge probe wires are ran inside the conduit and connected to the diode element  304  at the tip of the probe which is used as a sensor. 
     The flexibility of the probe  320  carrying the sensor  304  provides significant advantages over the conventional probe thermometers used currently in the HVAC field, which are always rigid and straight, though the entire device can be positioned in many different angles. The current rigid straight probes used in the HVAC industry, although accurate, are limited in the ability to enter remote, difficult to reach places, as for example an internal air vent register, because they cannot get past the curved blades of a register grill easily. Even when penetration between the blades of a register is achieved by a conventional probe, the tip of the probe will be shallow in the air stream and the available adjustments are minimal. In contrast, the flexible probe  320  is much more versatile in terms of being able to enter deep in between the curved blades of a metal air vent register so the probe can be put inside the vent and in direct path of flowing conditioned air where there is no other unconditioned ambient air that can mix with the targeted conditioned air and cause an inaccurate air temperature reading. The ability to place the sensor inside the air vent register where only conditioned air is present is vital in successfully recording the most accurate temperature reading as possible. This mode of operation enables the user to obtain accurate air temperature readings that may be then used by the target super heat and sub cooling formula, and by the temperature split formula for calibrating the operation of an AC system, to obtain a system running at maximum efficiency. 
     The temperature sensing unit  310  of telescopic thermometer  300  also includes releasable attachment  306  enabled to releasably attach the thermometer  300  to an appliance or a nearby point of interest. In the embodiment of  FIG. 3 , the attachment  306  includes an adjustable magnetic swivel head  307 . The adjustable magnetic swivel head  307  is placed at the very top of the telescopic body  302 . The purpose of the magnetic swivel head  307  is enable a technician to attach the entire telescopic thermometer  300  magnetically to a metal air vent register located high on the ceiling or high on a wall, while standing on the floor, without the use of a ladder. 
     As in the embodiment of  FIG. 2 , a display unit  320  is provided at the gripping end of the telescopic body  302 . This unit preferably includes an electronic temperature display (screen)  316  facing downwards when the thermometer  300  is in the vertical position, so that when the technician is below the dangling thermometer  300  he/she can look upwards at the screen  316  and read the temperature being recorded by the flexible probe  320  with sensor  304  placed inside the air vent. This gives the technician a major advantage, as it provides him/her with the best of both worlds: the accuracy of a conventional electronic probe thermometer and the ability to reach high elevated air vents without a ladder just like an infrared laser thermometer. In addition, it enables the technician to perform other operations while the thermometer performs the measurement, including noting the readings. 
     In one embodiment, the display unit  320  and the sensor  304  are connected to each other by two very thin gauge wires  322 ,  324  that are housed together in a single plastic-coated shell  318  that is a coil and acts like a slinky, as seen in  FIG. 3B .  FIG. 3B  shows the inside of the body  302  and of the probe  320 . When the telescopic body  302  is extended to full length, the slinky coil  318  uncoils, and recoils when the thermostatic body is retracted to ensure that the wire connections are not in danger of being pulled out by pressure when the body  302  is extended or crushed when the body is retracted. The wires  322 ,  324 , exiting the slinky coil  318  are connected to the display unit  320  at the gripping end, as shown in the enlargement B in  FIG. 3B . At the remote end, the wires  322 ,  324  exit the slinky coil  318  and connect to the wires  342 ,  344 . The wires  342 ,  344  are housed in a protective plastic shell  316  to ultimately connect the sensor  304  to the display unit. This arrangement is shown in enlargement C. Alternatively, the wires  342 ,  344  may run unprotected inside the probe  320 . 
     The magnetic swivel head  307  is also unique because it has the ability to lock in angles within one radian. This feature is provided for air vents in other settings than the ceiling. Not all air vents are placed up on a horizontal ceiling. It is common for air vents to be placed high on a vertical wall, for example, right above a bedroom door. In this scenario, in order for the magnetic swivel head  307  to stick properly to the grill on a vertical wall, the proper angle would need to be locked in on the magnetic swivel head  307 . For example, in the first scenario the air vent register was on the horizontal ceiling. In such a scenario, the surface of the magnetic swivel head 37 had to be locked in at a 90° angle with the magnets pointing up, as shown in  FIG. 3B . In the second scenario, with the air register on the vertical wall, the magnetic surface must be locked in at an 180° angle with the magnet pointing toward the wall and the thermometer body  302  parallel with the vertical wall, as shown in  FIG. 3A . This angle allows the magnet to support the weight of the entire thermometer  300 . Before the magnetic swivel head  307  is raised up and attached to the air vent the flexible probe  320  will also need to be bent into a near 180° angle direction so when the magnetic swivel head is raised and attached to the air vent the flexible probe  320  easily enters between the blades of the air vent register and into the internal stream of the conditioned air. 
       FIGS. 4A and 4B  show the mode of operation of the telescopic thermometer  300  in two different scenarios. For example, a technician will enter a home and locate an air vent register in the ceiling. The technician would then take out his telescopic thermostat  300 , extend the telescopic body  302  to a length that would reach the metal air vent register, then extending his arms towards the ceiling with his hands on the gripper end  302 - 2  raising the magnetic swivel head  307  up towards the metal air vent and attaching the magnet surface of the head to the metallic air vent register magnetically, while positioning the flexible probe  320  inside the air vent register in direct contact with the conditioned air stream. The technician needs also to ensure that the probe is not in contact with any surface, if the air temperature measurement is to be measured. 
     After the magnetic swivel head  307  has been attached magnetically to the air vent register, the technician would let go of the entire thermometer unit  300  from the gripping end  302 - 2  and leave the thermometer  300  stuck to the air vent with the extended telescopic body  302  dangling from the air vent in midair, with the gripping end  302 - 2  of the of the thermometer  300  over the head of the technician, within arm length. In this way, the technician will be able to pull and detach the thermometer  300  from the vent after the temperature measurement. 
     Other advantages are while the telescopic thermostat  300  is stuck to the air vent and reading air temperature, it takes a few minutes for the warm probe to cool down to the accurate air temperature. While the probe cool-down takes place, the technician hands are free to perform other tasks involved in an a/c repair. For example, the technician can check the refrigerant pressure or change the air filter. 
     After any additional tasks are complete, the technician will return to the telescopic thermostat  300  that is dangling from the air vent, look up at the screen  309  and record the temperature. The technician will then grab the bottom gripper that is within arm reach, pull down and detach the magnetic swivel head  307  from the air vent register. The technician will then push down on the telescopic body  302  to retract it to its smallest length, then put it away in a tool bag to most likely be used again on the next service call. 
     Reference throughout this specification to “one embodiment”, “an embodiment”, or “a specific embodiment” or similar terminology means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment and may not necessarily be present in all embodiments. Thus, respective appearances of the phrases “in one embodiment”, “in an embodiment”, or “in a specific embodiment” or similar terminology in various places throughout this specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, or characteristics of any particular embodiment may be combined in any suitable manner with one or more other embodiments. Other variations and modifications of the embodiments described and illustrated herein are possible in light of the teachings herein and are to be considered as part of the spirit and scope of the invention.