GB2052227A
Expired / Lapsed
GB
⏱️ 0.0 years remaining
Improvements in Electric Immersion Heaters
Assignee: Individual
•
Filing: 1979-06-29
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Granted: —
•
Expires: 1999-06-29
Abstract
Abstract An electric immersion heater particularly for an electric kettle comprises a heater element having a stainless steel sheath mounted in an element head also formed of stainless steel or the like. The head is pressed out and formed from a sheet to provide a cup shaped member having a helical rim formed at its outside end and engaged with an internal thread in mounting ring 14. The hot return portion 6 of the element is brazed to the head opposite a snap acting actuator 12 forming a thermal cut out. The head is mounted in the wall 13 of a kettle employing a sealing washer 15, which need not be as heat resistant as hitherto in view of the poor thermal conductivity of the head resulting in a lower overshoot temperature at the periphery. <IMAGE>
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
GB
Data Source
google_patents
Last Synchronized
2026-11-08 03:41
CPC Classifications
A; A47; A47J; A47J27/00; A47J27/21; A47J27/21008; A47J27/21016; H; H05; H05B; H05B3/00; H05B3/02; H05B3/04; H05B3/78; H05B3/82
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
91 words
An electric immersion heater comprising a heater element mounted in an element head and a thermal control unit including a thermally responsive actuator arranged to open a switch on overheating of the element to terminate the power supply thereto in which the element head includes a plate of flat or dished configuration formed from metal sheet having a thickness of between 0.3mm and 1 mm and low thermal conductivity as compared with brass, the element having a hot return portion thermally connected to the head in close proximity to the actuator.
Claim 2
Dependent Claim
91 words
An electric immersion heater comprising a heater element mounted in an element head and a thermal control unit including a thermally responsive actuator arranged to open a switch on overheating of the element to terminate the power supply thereto in which the element head includes a plate of flat or dished configuration formed from metal sheet having a thickness of between 0.3mm and 1 mm and low thermal conductivity as compared with brass, the element having a hot return portion thermally connected to the head in close proximity to the actuator.
Claim 3
Dependent Claim
19 words
An immersion heater according to claim 1 in which the thickness of the head is less than 0.75 mm.
Claim 4
Dependent Claim
17 words
An immersion heater according to claim 2 in which the thickness of the head is substantially 0.5mm.
Claim 5
Dependent Claim
22 words
An immersion heater according to claim 1,2 or 3 in which the head is made of stainless steel,
Monel, Inconel or Incoloy.
Claim 6
Dependent Claim
32 words
An immersion heater according to any of the preceding claims in which the hot return portion is connected to the element head over a confined area spaced inwardly from the periphery thereof.
Claim 7
Dependent Claim
25 words
An immersion heater according to claim 5 in which the head is formed with a raised portion to which the hot return portion is connected.
Claim 8
Dependent Claim
38 words
An immersion heater according to claim 6 in which the raised portion is pressed out of the head so as to form a depression on the other side which snugly receives and provides a mounting for the actuator.
Claim 9
Dependent Claim
49 words
An immersion heater according to any of the preceding claims in which the head is provided with an integral cylindrical flange adapted to be passed through the kettle wall mounting aperture, the outer end of said flange being provided with a helical rim forming substantially a single thread turn.
Claim 10
Dependent Claim
30 words
An immersion heater according to any of the preceding claims in which the element is substantially 51 Omm long and has a watts density of at least 55 watts cm-1.
Claim 11
Dependent Claim
25 words
An immersion heater according to any of the preceding claims in which the cross section of the element is D-shaped or of race track section.
Claim 12
Dependent Claim
109 words
An electric immersion heater comprising a heater element and a thermal control unit, the heater element having an element head and a hot return portion of the element being thermally connected to the element head, the element head having a relatively low thermal conductivity as compared that of brass, a control unit of the heater including an electrical switch and a thermally responsive switch actuator being arranged to detect heat from said head at a position in proximity to said thermal connection of said hot return portion to said head, and said switch actuator being taken from a selected batch of actuators having operating temperatures of at least 1400C+100C.
Claim 13
Dependent Claim
109 words
An electric immersion heater comprising a heater element and a thermal control unit, the heater element having an element head and a hot return portion of the element being thermally connected to the element head, the element head having a relatively low thermal conductivity as compared that of brass, a control unit of the heater including an electrical switch and a thermally responsive switch actuator being arranged to detect heat from said head at a position in proximity to said thermal connection of said hot return portion to said head, and said switch actuator being taken from a selected batch of actuators having operating temperatures of at least 1400C+100C.
Claim 14
Dependent Claim
110 words
An electric immersion heater comprising a heater element and a thermal control unit, the heater element having an element head and a hot return portion of the element being thermally connected to the element head, the element being in the form of an elongate cylindrical member having a minimum watts density ratio of 55 watts cm-', the element head having a relatively low thermal conductivity as compared with brass, a control unit of the heater including an electrical switch and a thermally responsive switch actuator being arranged to detect heat from said head at a position in proximity to said thermal connection of said hot return portion to said head.
Claim 15
Dependent Claim
110 words
An electric immersion heater comprising a heater element and a thermal control unit, the heater element having an element head and a hot return portion of the element being thermally connected to the element head, the element being in the form of an elongate cylindrical member having a minimum watts density ratio of 55 watts cm-', the element head having a relatively low thermal conductivity as compared with brass, a control unit of the heater including an electrical switch and a thermally responsive switch actuator being arranged to detect heat from said head at a position in proximity to said thermal connection of said hot return portion to said head.
Claim 16
Dependent Claim
117 words
An electric immersion heater comprising a heater element and a thermal control unit, the heater element having an element head and a hot return portion of the element being thermally connected to the element head, the element being in the form of an elongate cylindrical member having an outer tubular sheath of a material having a low thermal conductivity as compared with copper, the element head having a relatively low thermal conductivity as compared with brass, a control unit of the heater including an electrical switch and a thermally responsive switch actuator being arranged to detect heat from said head at a position in proximity to said thermal connection of said hot return portion to said head.
Claim 17
Dependent Claim
117 words
An electric immersion heater comprising a heater element and a thermal control unit, the heater element having an element head and a hot return portion of the element being thermally connected to the element head, the element being in the form of an elongate cylindrical member having an outer tubular sheath of a material having a low thermal conductivity as compared with copper, the element head having a relatively low thermal conductivity as compared with brass, a control unit of the heater including an electrical switch and a thermally responsive switch actuator being arranged to detect heat from said head at a position in proximity to said thermal connection of said hot return portion to said head.
Claim 18
Dependent Claim
42 words
An electric immersion heater according to any of the preceding claims in which the element sheath is formed of stainless steel. 1 5. An electric immersion heater substantially as hereinbefore described with reference to Figs. 1 to 4 of the accompanying drawings.
References Cited (Backward Citations)
No citation records indexed.
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