US3885129A - Positive temperature coefficient resistor heater - Google Patents

Positive temperature coefficient resistor heater Download PDF

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Publication number
US3885129A
US3885129A US446858A US44685874A US3885129A US 3885129 A US3885129 A US 3885129A US 446858 A US446858 A US 446858A US 44685874 A US44685874 A US 44685874A US 3885129 A US3885129 A US 3885129A
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United States
Prior art keywords
electrodes
ptcr
heater
disc
ptcr heater
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Expired - Lifetime
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US446858A
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English (en)
Inventor
John H Fabricius
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Sprague Electric Co
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Sprague Electric Co
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Filing date
Publication date
Application filed by Sprague Electric Co filed Critical Sprague Electric Co
Priority to US446858A priority Critical patent/US3885129A/en
Priority to CA217,538A priority patent/CA1012596A/en
Priority to JP1975027696U priority patent/JPS50113944U/ja
Application granted granted Critical
Publication of US3885129A publication Critical patent/US3885129A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/02—Details
    • H05B3/06—Heater elements structurally combined with coupling elements or holders
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/10—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor
    • H05B3/12—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor characterised by the composition or nature of the conductive material
    • H05B3/14—Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor characterised by the composition or nature of the conductive material the material being non-metallic
    • H05B3/141—Conductive ceramics, e.g. metal oxides, metal carbides, barium titanate, ferrites, zirconia, vitrous compounds
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B3/00—Ohmic-resistance heating
    • H05B3/68—Heating arrangements specially adapted for cooking plates or analogous hot-plates
    • H05B3/74—Non-metallic plates, e.g. vitroceramic, ceramic or glassceramic hobs, also including power or control circuits
    • H05B3/748—Resistive heating elements, i.e. heating elements exposed to the air, e.g. coil wire heater
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B2203/00—Aspects relating to Ohmic resistive heating covered by group H05B3/00
    • H05B2203/02—Heaters using heating elements having a positive temperature coefficient
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
    • H05B2213/00—Aspects relating both to resistive heating and to induction heating, covered by H05B3/00 and H05B6/00
    • H05B2213/07—Heating plates with temperature control means

Definitions

  • a temperature regulating heating element comprises a PTCR body having a surface with a pair of adjacent electrodes oppositely connected to a voltage source by two lead wires, respectively.
  • An electrically insulating layer may cover the electroded surface of the body to prevent shorting of the electrodes by a conducting object that is to be heated by thermal connection to the electroded surface.
  • a PTCR as a heating element whereby electrical energy is provided from a voltage supply to an electroded PTCR body and whereby the object to be heated and temperature regulated is placed adjacent to or surrounds the PTCR heating element. It is known to control the temperature of temperature sensitive electronic components in this way. Small ovens are also constructed employing these principles. It is also known to control and change the impedance of a second PTCR by placing it in thermal contact with a PTCR heating element.
  • the most commonly known PTCR element is characterized as having a sharp transition atthe so-called anomaly temperature, below which the electrical resistance of the PTCR is low and above which it is several orders of magnitude larger.
  • anomaly temperature below which the electrical resistance of the PTCR is low and above which it is several orders of magnitude larger.
  • Such PTCR heating elements are typically formed from a PTCR body having two opposite flat surfaces on which are deposited metal film electrodes which serve as the electrical terminals. Electrical current normally flows between these oppositely disposed electrodes through the PTCR body.
  • the load or object to be heated is thermally coupled to the body at one or both electrodes.
  • at least one of the electroded faces transmits thermal energy from the PTCR body to the load, and the regions of the body adjacent to the thermally coupling electrodes are most readily cooled thereby.
  • the PTCR body tends to switch or change to a high impedance at a plane within the body that is generally parallel to the electroded faces.
  • the aforementioned outer regions tend to remain below the anomaly temperature.
  • the temperature profile within the body from electrode to opposite electrode tends to have a maxima near the center of the body and decreasing therefrom to each electroded face.
  • the maxima is shifted toward the opposite electrode.
  • a temperature regulating heating element comprises a PTCR body, with two sets of alternately disposed electrodes bonded thereto. Each electrode is stripshaped and adjacent electrodes are members of opposite sets, such that when a voltage source is connected between the two electrode sets, electrical currents in the body tend to flow predominantly near the body surface between adjacent electrodes. Thus only a thin region of the PTCR body is interposed between a load, that is thermally connected to the electroded surface, and the dominant source of the heat that is located near the surface in the body.
  • An electrically insulating layer may be disposed over the electroded surface such that an electrically conductive object to be heated may be thermally coupled thereby to the electroded surface without shorting the electrodes to one anotherv BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. I is shown a top face view of a PTCR heating element according to a first preferred embodiment of the present invention.
  • FIG. 2 is shown a side view of the heating element of FIG. 1.
  • FIG. 3 is shown the bottom view of the heating element of FIG. I.
  • FIG. 4 is shown in perspective view the PTCR heating element of FIGS. 1, 2 and 3, having a voltage supply connected thereto.
  • FIG. 5 is shown a top face view of a PTCR heating element according to a second preferred embodiment.
  • FIG. 6 is shown a side view of the heating element of FIG. 5.
  • FIG. 7 is shown a bottom view of the heating element of FIG. 5.
  • FIG. 8 is shown in cross section a third preferred embodiment of a heating element of the present invention, the heating element of FIG. 5 having an insulative layer over the electrodes and being mounted in an insulative base, an object to be heated being mounted on the insulative layer.
  • FIG. 9 is shown a portion of FIG. 8 in magnified detail.
  • the PTCR body 10 has a disc shape having two opposite flat and mutually parallel faces and a perimeter face as seen in FIG. 2.
  • On the top face as seen in FIG. 1 are bonded two metal film electrodes 12 and 13, each having a long strip or more particularly a finger-like shape and being separated from each other by about the same distance along their respective lengths.
  • On the bottom or opposite face of body as seen in FIG. 3 there are two metal film electrodes l4 and each having a long finger-like shape and forming a pattern similar to that of electrodes 12 and 13 on the top face.
  • Electrodes I2 and 14 are connected to one terminal 27 of the supply 29 via lead wires 25 and 24, respectively, and electrodes 13 and 15 are connected to the other terminal 28 of the supply 29 via lead wires 23 and 22, respectively.
  • a voltage exists between interdigitated electrodes 12 and 13 on the top face, between electrodes 14 and 15 on the bottom face, between electrodes 12 and 15 over a portion of the perimeter face, and between electrodes 13 and 14 over another portion of the perimeter face.
  • the thickness of the body 10 is made to be about equal to the aforementioned distance between electrodes on the same face (e.g., l2 and 13 or 14 and 15), there is created a PTCR body 10, having on its surface a first set of electrodes (12 and 14) and interdigitated there with a second set of electrodes (13 and 15), each elec trode being disposed everywhere adjacent to and about equally distant from electrodes of the other set. Therefore adjacent electrodes are oppositely polarized and heating currents are caused to flow predominantly near the surface in the body 10.
  • the temperature regulating heating element of this first preferred embodiment is especially well suited for use as a liquid submersed heating element with substan tially all body surface areas being uniformly capable of transmitting heat to the surrounding liquid.
  • the electrodes on the bottom face namely 14 and 15, are removed or omitted.
  • FIGS. 5, 6 and 7 are shown a top, edge, and bottom view, respectively, of a second preferred embodiment of the present invention.
  • a plurality of metal film electrodes are bonded to the top face of the PTCR body 30. Each electrode is comprised predominantly of long strip or fingershaped portions, the distance between adjacent electrodes being approximately constant.
  • One set of electrodes 32 is interdigitated with respect to another set of electrodes 33.
  • a metal film 34 serves as a connective means tying the set of electrodes 32 together electrically, film 34 having been formed simultaneously with the electrode pattern and being contiguous with electrodes 32.
  • metal film 35 interconnects with the set of electrodes 33.
  • the two metal films 34 and 35 have extensions 36 and 37, respectively, that extend beyond the top face on to the peripheral face (see FIG. 6) and further onto the bottom face (see FIGv 7).
  • Two self-supporting leads may be con nected to any convenient point on the two metal film extensions 36 and 37, respectively; however extensions 36 and 37 themselves serve as film leads to electrode finger sets 32 and 33, respectively, When a voltage source, either a.c. or do is connected to the two leads,
  • the PTCR heating element will heat and regulate the temperature of an object that is placed in thermal contact with the top electroded face.
  • FIG. 8 is shown in cross section the PTCR heating element of FIG. 5, having a thin electrically insulative layer 39 bonded to and covering the top electroded face,
  • the body 30 is held by bonding or by mechanical fasteners (not shown) in a base made of an insulative material such as polysulfone, and is seated at mating surfaces 51 therein.
  • a cavity 52 is provided under the body 30 wherein a leaf spring 53, made for example of steel or of a beryllium-copper alloy, is compressed between the floor of the cavity and metal film extension 36 of the PTCR body.
  • Another leaf spring 54 (not shown) is similarly compressed between base 50 and the other metal film extension 37.
  • Leads 55 and 57 are connected to the leaf springs 53 and 54, respectively.
  • the leads 55 and 57 have insulating jackets 56 and S8, and they exit the base 50 through a hole provided for this purpose.
  • the electrode sets 32 and 33 are oppositely polarized.
  • a metal cup 60 is shown resting in contact with the insulative layer 39.
  • the cup 60 contains a liquid 61 to be heated and temperature regulated.
  • the insulative layer 39 provides electrical insulation between the metal cup 60 and the sets of electrodes 32 and 33.
  • the layer 39 is made only as thick as is necessary to provide this insulating function and may therefore be only a few thousandths of an inch thick over the electrodes when the voltage source is a 1 l0 V.a.c. line and the insulative layer material is a fluorocarbon resin such as Teflon (a Tradename of Dupont) or other high temperature insulating materials such as polysulfone, polyimide, or Parylene (a Tradename of Union Carbide).
  • a number of well known methods of applying a uniform insulating coating are suitable, such as depositing the resin in liquid form over the electroded face, curing at an elevated temperature and bonding the layer to the face. Also vapor deposition of Parylene provides an exceptionally uniform layer and requires no subsequent Curing.
  • the thin layer 39 additionally serves to provide the thermal coupling between the body 30 and the cup 60. It represents a small thermal resistance when its thick' ness to area of thermal contact is as small as 0.001 inch per square inches. However, about one order of magnitude smaller thermal resistance can be realized by mak ing the layer 39 of a ceramic, or glass, or a mixture thereof as described in US. Pat. No. 3,6l9,220 by Maher filed Sept. 26, I968.
  • FIG. 9 is shown a detail of FIG. 8 drawn to a larger scale, wherein a dotted line 300 represents an isothermal surface being at the PTCR anomaly temperature in the PTCR body 30. It is believed that such an isothermal surface exists very close to the electroded face when heat is being taken from that surface by an adjacent object such as the metal cup 60, and electric cur rents flow between adjacent electrodes 32 and 33 in the body 30.
  • the body region 300 is at a temperature below the PTCR anomaly temperature and the body region 30b is at a temperature above the anomaly temperature.
  • the electric heating currents are predominantly flowing in the surface region 30a, and the thermal resistance of the bulk of the body 30 is of no consequence to the dynamics of heating.
  • the conventional PTCR heating element employing oppositely polarized electrodes on opposite faces of a PTCR body operates in a manner analogous to an electrical series resistor circuit. That is, the relative power dissipated in each element is proportional to its resistance.
  • the surface of a conventionally electroded PTCR When the surface of a conventionally electroded PTCR is coupled to a thermal load its temperature will drop. This causes the incremental resistance to drop which lessens the power being dissipated at the surface, and consequently the most power is generated in the warmer higher resistance portions of the PTCR element. Thus the power must be transferred from the higher resistance area deeper within the ceramic through the thermal resistance of the cooler surface layer.
  • electrical heating currents are forced to flow predominantly near the PTCR body surface between adjacent and oppositely polarized electrodes that are disposed thereon, thus decreasing the distance and therefore the thermal resistance between the major source of heat and the object being heated.
  • Prototypes were made according to the third preferred embodiment as shown in FIGS. 5, 6 and 7.
  • the body is comprised of a standard barium titanate doped with niobium as is described in the paper.
  • PTCR Substrate Heaters for Planar Silicon Devices by F. Kahn presented at the Electronics Components Conference in Washington, DC, in May 1972. In principle any PTCR material will be appropriate.
  • the PTCR disc shaped body had a diameter of 1.2 inches and a thickness of 0.1 inch.
  • the electrodes were formed by a standard silver paste screening and firing process.
  • Conven tional PTCR heaters were also made using PTCR bodies as above described but having solid film electrodes oppositely disposed on the two large surfaces. The conventional units served as controls in subsequent testing.
  • the prototypes and the controls were thermally coupled to an aluminum block (weighing 1,050 grams) via an interspersed 0.001 inch thick sheet of MYLAR (a Dupont Tradename for polyethyleneterephthalate) and connected to the I V.a.c. line.
  • MYLAR a Dupont Tradename for polyethyleneterephthalate
  • Table I are shown the best results, where r is the time to raise the temperature of the aluminum block by C, I,,,- is the average current drawn, and lp is the peak inrush current.
  • the prototypes made according to this invention raised the temperature of the block by 30C in about 30 percent less time than the time re quired for the controls.
  • the inrush to aver age current of the prototypes was less than a quarter of that in the controls.
  • a PTCR heater comprising a disc of PTCR material, said disc having two opposed flat surfaces and a perimeter face, a first pair of arcuate interdigitated metal film electrodes bonded to one of said surfaces, said electrodes each having a finger-like shape, the separation between adjacent portions of said electrodes being substantially constant, an electrical connective means for connecting the alternative of said electrodes to one lead and the remained of said electrodes to an other lead, said leads being capable of connection to an electrical energy source such that said adjacent electrodes are oppositively polarized and the heating electric currents in said disc flow predominantly near said one of said surfaces.
  • a second pair of arcuate interdigitated electrodes is bonded to the other of said surfaces, said second pair of electrodes having a pattern similar to the pattern of said first pair of electrodes, said disc having a thickness substantially equal to said separation.
  • the PTCR heater of claim 1 additionally comprising an electrically insulating layer disposed over said electrode pattern and over the intervening areas of said surface.
  • PTCR heater of claim 5 wherein said insulating layer consists of glass.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Ceramic Engineering (AREA)
  • Resistance Heating (AREA)
  • Surface Heating Bodies (AREA)
US446858A 1974-02-28 1974-02-28 Positive temperature coefficient resistor heater Expired - Lifetime US3885129A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US446858A US3885129A (en) 1974-02-28 1974-02-28 Positive temperature coefficient resistor heater
CA217,538A CA1012596A (en) 1974-02-28 1975-01-08 Positive temperature coefficient resistor heater
JP1975027696U JPS50113944U (ja) 1974-02-28 1975-02-28

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Cited By (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5216054U (ja) * 1975-07-23 1977-02-04
JPS5252754U (ja) * 1975-10-15 1977-04-15
JPS5256635U (ja) * 1975-10-22 1977-04-23
JPS5263748U (ja) * 1975-11-07 1977-05-11
JPS5258139A (en) * 1975-11-08 1977-05-13 Murata Manufacturing Co Method of producing heater using positive characteristic thermistor
US4037082A (en) * 1976-04-30 1977-07-19 Murata Manufacturing Co., Ltd. Positive temperature coefficient semiconductor heating device
JPS5298844U (ja) * 1976-01-23 1977-07-26
JPS5298845U (ja) * 1976-01-23 1977-07-26
DE2619312A1 (de) * 1976-01-23 1977-07-28 Murata Manufacturing Co Halbleiter-heizelement
DE2619242A1 (de) * 1976-04-30 1977-11-10 Murata Manufacturing Co Heizvorrichtung mit einem halbleiter-heizelement mit positivem temperaturkoeffizienten
US4058701A (en) * 1974-05-14 1977-11-15 Schoeller & Co. Elektrotechnische Fabrik Gmbh & Co. Glow element arrangement for electric cigarette lighters
FR2350032A1 (fr) * 1976-04-30 1977-11-25 Murata Manufacturing Co Dispositif chauffant a semiconducteur a coefficient de temperature positif
US4092520A (en) * 1976-12-16 1978-05-30 Baxter Travenol Laboratories, Inc. Leakage current thermostat
US4107515A (en) * 1976-09-09 1978-08-15 Texas Instruments Incorporated Compact PTC resistor
US4180901A (en) * 1976-09-09 1980-01-01 Texas Instruments Incorporated Compact PTC resistor
US4236065A (en) * 1978-12-06 1980-11-25 Texas Instruments Incorporated Self-regulating electric heater
US4242567A (en) * 1978-06-05 1980-12-30 General Electric Company Electrically heated hair straightener and PTC heater assembly therefor
US4282003A (en) * 1978-12-06 1981-08-04 Texas Instruments Incorporated Method for constructing a self-regulating electric heater
US4574187A (en) * 1980-08-29 1986-03-04 Sprague Electric Company Self regulating PTCR heater
US4972067A (en) * 1989-06-21 1990-11-20 Process Technology Inc. PTC heater assembly and a method of manufacturing the heater assembly
US6172592B1 (en) * 1997-10-24 2001-01-09 Murata Manufacturing Co., Ltd. Thermistor with comb-shaped electrodes
US6246032B1 (en) 1990-04-14 2001-06-12 Thomas A. Quinn Hot beverage flavor protector
US20040149717A1 (en) * 2003-01-30 2004-08-05 Chia-Hsiung Wu Constant temperature sealed cooking device
US7034259B1 (en) 2004-12-30 2006-04-25 Tom Richards, Inc. Self-regulating heater assembly and method of manufacturing same
US20080122031A1 (en) * 2006-07-11 2008-05-29 Rockwell Scientific Licensing, Llc Vertical electrical device
US20080314893A1 (en) * 2007-06-25 2008-12-25 Adair Joel E Heating device with adjusting electrical contact
US20150305094A1 (en) * 2014-04-16 2015-10-22 Spectrum Brands, Inc. Portable container system for heating a beverage
US9854824B2 (en) 2014-04-16 2018-01-02 Spectrum Brands, Inc. Heating appliance
US20210144810A1 (en) * 2019-10-09 2021-05-13 Mahle International Gmbh Ptc heating element and a ptc heating module

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5929359Y2 (ja) * 1976-02-09 1984-08-23 株式会社村田製作所 正特性サ−ミスタを用いた発熱体装置
JPS5934067Y2 (ja) * 1976-03-09 1984-09-21 株式会社村田製作所 正特性サ−ミスタを用いた発熱体装置
JPS5613746Y2 (ja) * 1976-03-10 1981-03-31
JPS5933194Y2 (ja) * 1976-03-10 1984-09-17 株式会社村田製作所 正特性サ−ミスタを用いた発熱体装置
JPS5934068Y2 (ja) * 1976-03-10 1984-09-21 株式会社村田製作所 正特性サ−ミスタを用いた発熱体装置
JPS6019347Y2 (ja) * 1976-12-21 1985-06-11 株式会社村田製作所 正特性サ−ミスタを用いた発熱体装置
JPS53101739A (en) * 1977-02-18 1978-09-05 Toshiba Corp Exothermic device
JPS6029196Y2 (ja) * 1977-03-18 1985-09-04 株式会社村田製作所 正特性サ−ミスタを用いた発熱体装置
JPS6029197Y2 (ja) * 1977-03-30 1985-09-04 株式会社村田製作所 正特性サ−ミスタを用いた発熱体装置

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2804581A (en) * 1953-10-05 1957-08-27 Sarkes Tarzian Semiconductor device and method of manufacture thereof
US3092704A (en) * 1959-12-28 1963-06-04 Ace Glass Inc Resistance coating for articles of glassware and the like
US3375774A (en) * 1967-01-05 1968-04-02 Matsushita Electric Ind Co Ltd Fully automatic electric coffee pot
US3452314A (en) * 1967-05-22 1969-06-24 Victory Eng Corp Low noise thermistor assembly and method
US3645785A (en) * 1969-11-12 1972-02-29 Texas Instruments Inc Ohmic contact system
US3719796A (en) * 1970-08-14 1973-03-06 Danfoss As Heating unit having a ptc heating resistor
US3767597A (en) * 1970-07-15 1973-10-23 Matsushita Electric Ind Co Ltd High temperature thermistor composition

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5213745B2 (ja) * 1972-04-17 1977-04-16

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2804581A (en) * 1953-10-05 1957-08-27 Sarkes Tarzian Semiconductor device and method of manufacture thereof
US3092704A (en) * 1959-12-28 1963-06-04 Ace Glass Inc Resistance coating for articles of glassware and the like
US3375774A (en) * 1967-01-05 1968-04-02 Matsushita Electric Ind Co Ltd Fully automatic electric coffee pot
US3452314A (en) * 1967-05-22 1969-06-24 Victory Eng Corp Low noise thermistor assembly and method
US3645785A (en) * 1969-11-12 1972-02-29 Texas Instruments Inc Ohmic contact system
US3767597A (en) * 1970-07-15 1973-10-23 Matsushita Electric Ind Co Ltd High temperature thermistor composition
US3719796A (en) * 1970-08-14 1973-03-06 Danfoss As Heating unit having a ptc heating resistor

Cited By (38)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4058701A (en) * 1974-05-14 1977-11-15 Schoeller & Co. Elektrotechnische Fabrik Gmbh & Co. Glow element arrangement for electric cigarette lighters
JPS5216054U (ja) * 1975-07-23 1977-02-04
JPS5252754U (ja) * 1975-10-15 1977-04-15
JPS5256635U (ja) * 1975-10-22 1977-04-23
JPS5910712Y2 (ja) * 1975-10-22 1984-04-03 株式会社村田製作所 正特性サ−ミスタを用いた発熱体装置
JPS5263748U (ja) * 1975-11-07 1977-05-11
FR2331229A1 (fr) * 1975-11-07 1977-06-03 Murata Manufacturing Co Unite de chauffage de fluide
JPS5553100Y2 (ja) * 1975-11-07 1980-12-09
JPS5258139A (en) * 1975-11-08 1977-05-13 Murata Manufacturing Co Method of producing heater using positive characteristic thermistor
JPS5614221B2 (ja) * 1975-11-08 1981-04-02
DE2619312A1 (de) * 1976-01-23 1977-07-28 Murata Manufacturing Co Halbleiter-heizelement
FR2339313A1 (fr) * 1976-01-23 1977-08-19 Murata Manufacturing Co Element chauffant a semiconducteur a coefficient de temperature positif
JPS5298845U (ja) * 1976-01-23 1977-07-26
JPS5298844U (ja) * 1976-01-23 1977-07-26
DE2619242A1 (de) * 1976-04-30 1977-11-10 Murata Manufacturing Co Heizvorrichtung mit einem halbleiter-heizelement mit positivem temperaturkoeffizienten
FR2350032A1 (fr) * 1976-04-30 1977-11-25 Murata Manufacturing Co Dispositif chauffant a semiconducteur a coefficient de temperature positif
US4037082A (en) * 1976-04-30 1977-07-19 Murata Manufacturing Co., Ltd. Positive temperature coefficient semiconductor heating device
US4107515A (en) * 1976-09-09 1978-08-15 Texas Instruments Incorporated Compact PTC resistor
US4180901A (en) * 1976-09-09 1980-01-01 Texas Instruments Incorporated Compact PTC resistor
US4092520A (en) * 1976-12-16 1978-05-30 Baxter Travenol Laboratories, Inc. Leakage current thermostat
US4242567A (en) * 1978-06-05 1980-12-30 General Electric Company Electrically heated hair straightener and PTC heater assembly therefor
US4236065A (en) * 1978-12-06 1980-11-25 Texas Instruments Incorporated Self-regulating electric heater
US4282003A (en) * 1978-12-06 1981-08-04 Texas Instruments Incorporated Method for constructing a self-regulating electric heater
US4574187A (en) * 1980-08-29 1986-03-04 Sprague Electric Company Self regulating PTCR heater
US4972067A (en) * 1989-06-21 1990-11-20 Process Technology Inc. PTC heater assembly and a method of manufacturing the heater assembly
US6246032B1 (en) 1990-04-14 2001-06-12 Thomas A. Quinn Hot beverage flavor protector
US6172592B1 (en) * 1997-10-24 2001-01-09 Murata Manufacturing Co., Ltd. Thermistor with comb-shaped electrodes
US20040149717A1 (en) * 2003-01-30 2004-08-05 Chia-Hsiung Wu Constant temperature sealed cooking device
US6909072B2 (en) * 2003-01-30 2005-06-21 Chia-Hsiung Wu Constant temperature sealed cooking device
US7034259B1 (en) 2004-12-30 2006-04-25 Tom Richards, Inc. Self-regulating heater assembly and method of manufacturing same
US20080122031A1 (en) * 2006-07-11 2008-05-29 Rockwell Scientific Licensing, Llc Vertical electrical device
US7989915B2 (en) * 2006-07-11 2011-08-02 Teledyne Licensing, Llc Vertical electrical device
US20080314893A1 (en) * 2007-06-25 2008-12-25 Adair Joel E Heating device with adjusting electrical contact
WO2009002431A1 (en) * 2007-06-25 2008-12-31 S. C. Johnson & Son, Inc. Heating device with adjusting electrical contact
US20150305094A1 (en) * 2014-04-16 2015-10-22 Spectrum Brands, Inc. Portable container system for heating a beverage
US9642191B2 (en) * 2014-04-16 2017-05-02 Spectrum Brands, Inc. Portable container system for heating a beverage
US9854824B2 (en) 2014-04-16 2018-01-02 Spectrum Brands, Inc. Heating appliance
US20210144810A1 (en) * 2019-10-09 2021-05-13 Mahle International Gmbh Ptc heating element and a ptc heating module

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Publication number Publication date
JPS50113944U (ja) 1975-09-17
CA1012596A (en) 1977-06-21

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