Heating element and method of use thereof

Abstract

A heating element and method of using the same are disclosed. The heating element includes a first terminal and a second terminal and one or more heating element segments extending between the first terminal and the second terminal. The one or more heating element segments have a circuit trace including at least a first portion and a second portion configured such that there is a surface temperature difference between the at least first portion and second portion when a voltage is applied between the first terminal and the second terminal. The heating element can also be formed into a three-dimensional shape, including a shape created by securing the heating element to one or more support plates. The heating element can also have a cylindrical shape and be disposed in an insulating medium in a tubular member to provide varying heating capabilities along the length of the tubular member.

Description

[0001] This application claims priority to U.S. Provisional Patent Application 63 / 010,922, filed April 16, 2020, pursuant to 35 USC 119(e), the entire contents of which are incorporated herein by reference. Invention Field

[0002] The present invention discloses a heating element with a Z-shaped pattern, which includes a unique structure that can be used in a variety of heating applications. Background Technology

[0003] Extended heating elements are well known in the field of heating elements. U.S. Patent No. 3,789,417, granted to Bittner, is an example of an extended heating element assembly that includes a zigzag pattern of heating element material that also creates openings in the heating element material.

[0004] Other patterned heating elements are disclosed in U.S. Patent No. 7,763,833 to Hindel et al., U.S. Patent No. 7,211,772 to Carpino II et al., and pre-grant U.S. Patent Application No. 2007 / 0164015 to Carpino II et al., all of which have been assigned to Goodrich Corporation. In most cases, the patterned heating elements patented by Goodrich are foils primarily used for de-icing applications.

[0005] While these heating elements offer flexibility for use in various applications due to their thin size, improvements in heating element design are still needed to provide more functionality and flexibility for these types of elements used in different applications.

[0006] Another heating element was disclosed in the publication of U.S. Patent Application No. 2019 / 0008322, prior to its grant to Feldman et al., the entire contents of which are incorporated herein by reference. Figure 1-4 Describe the heating element.

[0007] Now for reference Figure 1 and 2 One embodiment of the heating element is indicated by reference numeral 100 and includes terminals 101 (including terminals 101A and 101B). Heating element segments 103 (including segments 103A-F) and busbars 105 (including busbars 105A-E) are also included. Figure 1 and 2In the example shown, heating element 100 includes six heating element segments 103A-F connected together via five buses 105A-105E; however, in other examples, heating element 100 may include more or fewer heating element segments 103. Other examples may include heating element segments 103 in numbers ranging from about 1 to about 20 or from about 2 to about 12. Some examples may have an even number of heating element segments 103, such as 2, 4, 6, 8, 10, or 12.

[0008] Heating element 100 has a total width W2, and each heating element segment 103 has a width W1. The total width W2 is greater than the sum of the widths W1 of each heating element segment 103 in heating element 100. In some examples, the total width W2 of the heating element is about 35% to about 45% greater than the sum of the widths W1 of one or more heating element segments. In some examples, the total width W2 of heating element 101 is in the range of about 2 inches to about 18 inches, or in the range of about 3 inches to about 12 inches, or in the range of about 4 inches to about 6 inches.

[0009] The heating element 100 includes terminals 101A and 101B disposed at opposite ends of the heating element 100. Terminal 101 is a conductive contact for connecting the heating element 100 to a power source or other heating element. In this example, terminals 101A and 101B are also respectively connected to at least one heating element segment 103 of the heating element 100. For example, terminal 101A is connected to one end of heating element segment 103A, while terminal 103B is connected to one end of heating element segment 103F.

[0010] The heating element segments 103 can be connected in series, thereby increasing the current path between terminals 101A and 101B compared to having only a single heating element segment 103. For example, the current path is at least six times the length L1 of the first heating element segment 103A. By increasing the current path between terminals 101A and 101B, the power supply can use a higher voltage (e.g., 110V, the same voltage source to which the device is plugged) and / or a lower current, which can help avoid the use of a power converter or otherwise reduce the component cost of a heating device that includes heating elements 100.

[0011] exist Figure 1 and Figure 2 In the example shown, heating element 100 has a total length L0, and the outermost heating element segments of the first group (e.g., segments 103A and 103F) have a first length L1, the innermost heating element segments of the second group (e.g., segments 103B and 103E) have a second length L2, and the innermost heating element segments of the third group (e.g., segments 103C and 103D) have a third length L3. Figure 1 and Figure 2In the example shown, three groups of heating element segments are depicted, with each group comprising two heating element segments. In other examples, a group of heating element segments may include a single heating element segment, or may include more than two heating element segments, and heating element 100 may include more or fewer than three groups of heating element segments.

[0012] The length (e.g., L1, L2, or L3) of each heating element segment 103 is greater than the width W2 of each heating element segment 103. The ratios of lengths L1, L2, L3 to width W2 can be selected sequentially to obtain the desired power output, current, and resistance. In some examples, the width W2 of the heating element segments 103 is in the range of about 0.1 inches to about 6 inches, or about 1 / 4 inch to about 1 inch. In some examples, the width W2 is about 1 / 2 inch. In some examples, the lengths L1-L3 of the heating element segments 103 can be in the range of about 2 inches to about 12 inches, or about 3 inches to about 8 inches. In some examples, the length L1 of the first group of heating elements is about 70% to about 90% of the length L3 of the third group of heating elements. In some examples, the length L2 of the second group of heating elements is about 80% to about 99% of the length L3 of the third group of heating elements.

[0013] exist Figure 1 and 2 In the heating element 100 shown, the bus 105A connecting heating element segments 103A and 103B has an elbow or bend shape to accommodate different lengths L1, L2 between these heating element segments. The bus 105E connecting heating element segments 103E and 103F also has an elbow or bend shape to accommodate different lengths L1, L2 between these heating element segments. Buses 105B, 105C, and 105D all have straight or linear shapes for connecting adjacent heating element segments (e.g., heating element segments 103B and 103C, heating element segments 103C and 103D, and heating element segments 103D and 103E). In some examples, the shapes of terminals 130 (e.g., terminals 101A-B) and buses 105 (e.g., buses 105A-E) can vary.

[0014] Buses 105A-E and terminals 101A, 101B each include one or more holes 107 to provide mechanical contact points. In some examples, electrically insulated mechanical supports are fastened to the holes 107 to hold terminals 101 and buses 105 in the desired position.

[0015] During operation, current can be supplied to the heating element 100 by electrically connecting terminals 101A and 101B to a power source. When current flows through the heating element 100, the material of the heating element segment 103 begins to heat and emit light. Typically, light emission begins at a temperature between about 500 and 550°C (about 1,000°F). When the heating element segments 103 emit light, they generate and emit infrared radiation. In some embodiments, the temperature of the heating element segments 103 is in the range of about 800°C to about 900°C, or about 850°C during operation.

[0016] Now for reference Figure 3 An enlarged view of the heating element 100 shows a heating element segment 103B extending between bus 105A and bus 105B. Each heating element segment 103A-F has a repeating pattern 109 formed by a plurality of cuts 111. The cuts 111 are spaced apart from each other in the repeating pattern 109 and are surrounded by rounded corners. In some examples, the repeating pattern 109 is formed by two columns of cuts 111 and a nested third column of cuts 111, which overlaps and / or is arranged between the first two columns of cuts. The repeating pattern 109 can allow the heating element 100 to provide uniform radiant heating.

[0017] Now for reference Figure 4 The cuts 111 have an elliptical shape, making them substantially elliptical or circular. For example, each cut 111 includes a first wall 113a and a second wall 113b, which are curved and extend in opposite directions along the vertical axis AA. In this way, each cut 111 is separated from another cut 111 along the vertical axis AA. Additionally, each cut 111 is linked to the opposite walls 113a, 113b of an adjacent cut 111. Each cut 111 is symmetrical about the two vertical axes AA and the horizontal axis BB.

[0018] The curved shape of the notch 111 increases the current path between the terminals 101A and 101B of the heating element 100, thereby allowing for higher voltages and / or lower currents to be used to heat the heating element 100. Furthermore, the notch 111 provides complex resistance paths, which can help reduce hot spots in the heating element 100.

[0019] like Figure 4 As shown, each cutout 111 may have a separate width W5 and a separate length L5. In some examples, the width W5 may range from about 0.20 inches to about 0.35 inches, and the length L5 may range from about 0.06 inches to about 0.16 inches.

[0020] Refer again Figure 1-4In some examples, the heating element 100 is a single sheet, such that terminals 101 (including terminals 101A and 101B), heating element segments 103 (including segments 103A-F), and bus 105 (including bus 105A-E) are all continuous with each other. Therefore, no separate elements or parts are used to connect terminals 101, heating element segments 103, and bus 105, as they are all part of the same continuous sheet. In some examples, the heating element 100 is a single sheet of iron-chromium-aluminum alloy or a similar alloy material. In other examples, the heating element 100 is a single sheet of an alloy of at least nickel and chromium, referred to as a nickel-chromium alloy.

[0021] To form the terminal 101, heating element segment 103, and bus 105 as a single piece of material, a blank sheet is cut from a roll of material and then processed. In some examples, photolithography is used to process the blank sheet to remove unwanted portions of the sheet by an etching process, leaving only the desired portion of the heating element 100. In some exemplary embodiments, the photolithography process includes applying a photoresist material to the surface of the blank sheet, aligning a photomask having a pattern opposite to that of the desired heating element 100 with the sheet and the photoresist, exposing the photoresist to ultraviolet light through the photomask, and removing the ultraviolet-exposed portions of the photoresist. Etching is then performed to remove those portions of the sheet not protected by the remaining photoresist. The remaining photoresist is then removed, leaving... Figure 1 and 2 The heating element 100 is shown. In some examples, since the sheet is not attached to the substrate during the photolithography process, the conductive material sheet is etched simultaneously from both sides.

[0022] The photolithography process optimizes the structure of the heating element 100 by providing a continuous and smooth transition between the terminals 101, heating element segment 103, and bus 105, which are all part of the same continuous material sheet. This improves the current flowing through the heating element 100 and thus improves the performance of the heating element 100, allowing the infrared radiation generated by the heating element 100 to reach higher temperatures in a shorter time.

[0023] In another possible example, other techniques such as machining and / or stamping are used to process the blank sheet to form the terminal 101, heating element segment 103, and bus 105 into a continuous single sheet. For example, machining or cutting can be performed by a computer numerical control (CNC) milling machine or similar machine.

[0024] By forming the terminals 101, heating element segments 103, and bus 105 entirely from a single sheet, the heating element 100 eliminates the need for any joints that fasten two separate metal sheets together. This is advantageous for several reasons. One benefit is that joints in the heating element are potential sources of failure because they oxidize over time due to exposure to electricity and oxygen. Oxidation reduces the conductivity at that point, thereby reducing the amount of current that can flow and creating cold spots. Therefore, eliminating joints improves operation and reduces the chance of undesirable oxidation occurring in the heating element 100. Another benefit is that all components (terminals, heating element segments, and bus) are connected together, thus eliminating the need for any manufacturing steps that connect these components together. Using the heating element of the present invention, long or short circuits with simple or complex shapes and traces can be easily designed and constructed without one or more electrical and / or mechanical bus components and designs. These complex shapes can easily incorporate heated circuit traces used to form profiles on complex surfaces while maintaining heat control over specific areas. Furthermore, the absence of additional fasteners not only improves quality and potential lifespan but also reduces costs and assembly labor. The traces can be folded while remaining intact without the need for fasteners that require a specific assembly sequence. Like paper dolls, heaters can be used for specific applications while ultimately maintaining homogeneity.

[0025] After the blank sheet of conductive material has been processed, the completed heating element 100 can have a thickness T1 (in Figure 2 (As shown in the diagram). The thickness T1 of the heating element 100 can be selected to achieve the desired power output, current, and resistance. In some examples, the thickness T1 ranges from about 1 / 8 mm to about 3 / 8 mm or about 1 / 4 mm. In some examples, the finished size and material of the heating element 100 enable it to receive about 55 V and produce about 350 W + / - 10% of energy. However, due to the ease of changing the type and thickness of the material alloy, and the simplicity of segment design, shape, and spacing, it is easy to conceive that it can produce almost any desired combination of practical voltage and power. Considering the many design factors that facilitate configuration and control, its use in heating is virtually limitless. Heaters can be conceived and manufactured for a wide variety of heating technologies, from convection or conduction types to radiant heating techniques.

[0026] However, it is still necessary to address issues such as... Figure 1-4 The heater elements shown are improved because their design causes manufacturing problems and, being essentially two-dimensional, their applications are more limited. This invention addresses this need by providing a variety of different heating element designs. Summary of the Invention

[0027] One object of the present invention is to provide an improved heating element.

[0028] Another object of the present invention is to provide a method for heating a space using an improved heating element.

[0029] To achieve the objectives and advantages associated with this invention, a first embodiment of the heating element of this invention includes a first terminal and a second terminal. The heating element also includes one or more heating element segments extending between the first and second terminals, each heating element segment having a plurality of cuts arranged in a repeating pattern, each cut having an elliptical or oval shape. The first and second terminals, as well as the one or more heating element segments, are a continuous single sheet.

[0030] In one embodiment, the heating segment can be divided into three groups. The first group of heating element segments has a first length, the second group of heating element segments has a second length, and the third group of heating element segments has a third length, with each group having the same length.

[0031] The present invention also includes a method for heating a space, the method comprising providing and powering a heating element of the present invention to generate infrared radiation for heating the space. This heating method may use any of the heating elements of the present invention disclosed herein.

[0032] In one aspect of the invention, a heating element is provided, comprising a first terminal and a second terminal, and one or more heating element segments extending between the first and second terminals. Each heating element segment has a plurality of cutouts arranged in a repeating pattern, each cutout having an elliptical or oval shape. The first and second terminals and the one or more heating element segments are a continuous single sheet, and wherein at least one of the first and second terminals includes an extension that can be folded relative to the heating element. In another embodiment, each of the first and second terminals may include an extension that can be folded relative to the heating element. Folding of the extension allows the heating element to stand upright alone in a given heating application, or to be used to mechanically attach the heating element to a desired structure or location.

[0033] The heating element may also include multiple heating element segments that extend in an arc shape. A set of arc-shaped heating element segments can be arranged to form a larger arc or circle.

[0034] In yet another embodiment, the heating element is configured such that its surface temperature varies across the entire heating element, thereby providing differential heating. In this embodiment, the heating element has at least a first terminal and a second terminal, and one or more heating element segments extending between the at least first terminal and the second terminal, the one or more heating element segments having circuit traces comprising at least a first portion and a second portion. The at least first portion and the second portion are configured such that a surface temperature difference exists between the at least first portion and the second portion when a voltage is applied between the at least first terminal and the second terminal.

[0035] Heating elements that provide differential heating can be made into three-dimensional shapes. The three-dimensional shape can be any one of the following: a semi-cylindrical shape, a cylindrical shape, and a sinusoidal shape.

[0036] The heating element of the present invention can also be used in tubular heater applications. That is, the heating element can have a cylindrical shape and be arranged in an insulating medium for heating. The insulating medium can be further located between the inner tube and the outer tube to differentially heat the material flowing through the inner tube.

[0037] The heating element can be configured to have different power connectors; for example, at least one power connector can be arranged between at least the first and second portions of a given circuit trace rather than at the terminals of the heating element.

[0038] Heating elements can also utilize individual bridging connections, which simplifies the design of heating elements and allows multiple heating elements with simpler shapes to be connected together using bridging connections.

[0039] For differential heating of the heating element, the circuit traces of the heating element can have different configurations. For example, the circuit traces can have multiple first rhombuses and multiple second rhombuses, with the multiple first rhombuses configured to have a lower resistance than the multiple second rhombuses.

[0040] Alternatively, the circuit trace may have multiple rhombuses, wherein the width of the multiple rhombuses gradually narrows continuously between at least the first terminal and the second terminal, or the width of one or more of the multiple rhombuses varies along the length of the circuit trace.

[0041] The circuit trace may also have multiple rhombuses, each rhombus having a wire harness width, and the width of the connection between at least one of the first terminal and the second terminal and the rhombus adjacent to at least one of the first terminal and the second terminal is greater than the wire harness width.

[0042] The circuit trace may also have at least a first set of rhombuses and a second set of rhombuses. The first set of rhombuses has a resistor and a first shape, and the second set of rhombuses has the same resistor and a second shape, the second shape being different from the first shape and constituting a smaller mass. When a voltage is applied to the circuit trace, the second set of rhombuses operates at a surface temperature higher than the surface temperature of the first set of rhombuses. The difference in shape may be based on one of the following: the width of the rhombus bundles in the circuit trace, the width of the rhombuses, the number of rhombuses in a set, or the internal width or height spacing between the bundles forming the rhombuses.

[0043] In addition to forming a heating element with a three-dimensional shape and using that three-dimensional shape in a given heating application, a heating element can be formed in a three-dimensional shape as part of a heater having a given support structure. In one embodiment, the heating element may or may not have the aforementioned differential heating capabilities. The heating element, together with one or more support plates, has a first shape, such as a flat state. When a portion of the heating element is attached to one or more support plates, the shape of the heating element differs from its original shape. For example, a two-dimensional planar shape, when attached to at least one support plate having a shape different from that of the heating element, produces a three-dimensional shape for the heating element, even if only by a difference in length. When a flat shape is used for the heating element, making the length of the heating element greater than the length of one or more support plates results in the heating element forming a three-dimensional sinusoidal shape.

[0044] While one support plate can be used, multiple support plates can also be used. In this embodiment, a portion of the heating element can be attached to the support plate first, and when the support plates are assembled together, the three-dimensional shape of the heating element is created. Attached Figure Description

[0045] Figure 1 This is a front view plan view of a first embodiment of a prior art heating element.

[0046] Figure 2 yes Figure 1 An isometric view of the heating element shown.

[0047] Figure 3 yes Figure 1 An enlarged view of the heating element shown.

[0048] Figure 4 yes Figure 1 Another enlarged view of the heating element shown.

[0049] Figure 5 A front view plan view of an embodiment of the heating element of the present invention is shown.

[0050] Figure 6 shows another embodiment of the heating element of the present invention, which is a single segment.

[0051] Figure 7 shows another single-stage heating element with improved terminals.

[0052] Figure 8 shows an enlarged view of the cut of the heating element in Figure 6.

[0053] Figure 9 Another embodiment of the present invention's heating element, which is fan-shaped, is shown.

[0054] Figure 10A and 10B It shows the use of Figure 9 Other heating element constructions of the heating element.

[0055] Figures 11a-11d Different diamond-shaped wire bundles constituting the heater traces of the present invention are shown.

[0056] Figure 12 An example of the heating element or heater trace of the present invention employing multiple wire harnesses is shown.

[0057] Figure 13a and 13b The heater traces of different sizes are shown.

[0058] Figure 14a and 14b Different sizes of heater tracks using more than one track are shown.

[0059] Figure 15 The heater trace using two different sub-traces is shown.

[0060] Figure 16 Heating elements with various types of traces are shown.

[0061] Figure 17 A conical heating element with multiple heater traces is shown.

[0062] Figures 18a and 18b show heater traces with different terminal configurations.

[0063] Figures 19a-19e show examples of heater traces of different shapes.

[0064] Figures 20a and 20b show heater traces with different wire harness shapes to achieve different heating effects.

[0065] Figure 21 Numerous heater traces are shown, which, together with jumper wires, form heating elements.

[0066] Figures 22a and 22b show heater traces, which can be designed for different heating applications depending on the connection of the terminals to the power supply.

[0067] Figures 23a and 23b show two different heater trace designs with intermediate power connectors.

[0068] Figure 24a -b shows the heater traces integrated with a mica plate as a radiant heater assembly.

[0069] Figure 25a -c shows a variation of a heater assembly that uses a pair of mica plates for conductive heating.

[0070] Figures 26a-b show another variation of the heater assembly using heater traces and mica plates as vertical heater assemblies.

[0071] Figure 27a -c shows a variation of the vertical heater assembly in Figure 26.

[0072] Figure 28a -b shows the heater traces formed in a three-dimensional shape.

[0073] Figure 29a -b shows the three-dimensional heater trace as part of a heating element using an insulator.

[0074] Figure 30 Another variation is shown, forming a three-dimensional heater trace for manufacturing a tubular heater.

[0075] Figure 31a -b shows another three-dimensional heater trace as part of the heater assembly, where the heater trace is pre-formed before heater assembly.

[0076] Figure 32a-3 2c illustrates another embodiment of the heater trace and heater assembly, wherein the heater trace has a three-dimensional shape when the heater assembly is assembled.

[0077] Figure 33a-3 3e shows Figure 32a-3 A variation of the heater assembly of 2c, wherein multiple mica plate supports are used when assembling the heater assembly.

[0078] Figures 34a-34e show another embodiment of the heater assembly, wherein the heater traces, as part of the heater assembly, are formed in a three-dimensional shape. Detailed Implementation

[0079] The following provides many different heating element designs that offer improvements to heating element design, as described above. Figure 1-4 As shown in the image.

[0080] Figure 5An embodiment of the heating element of the present invention is shown, indicated by reference numeral 200. The heating element 200 has terminals 201A and 201B, heating element segments 203A-F, and busbars 205A-205E.

[0081] and Figure 1 Compared to terminals 101A and 101B, terminals 201A and 201B are custom-designed. Specifically, each terminal 201A, 201B includes a fastener 207 fixed to the backplate 209. The terminals also include a connector 211 designed for connecting power cords or other heating elements.

[0082] Figure 5 The heating element 200 in Figure 1 One difference between the heating elements in these components is that the segment lengths are all the same. Due to this similarity in length, buses 205A-205E are identical and do not require... Figure 1 Any curved section or bend like the heating element 101.

[0083] Figures 6 and 7 illustrate other embodiments of the heating element of the present invention. In Figure 6, the heating element is indicated by reference numeral 300 and consists of a single heating segment 301 having opposing terminals 303A and 303B. The heating element 300 also has, as shown in the figure... Figure 1 The cuts 305 are arranged similarly to those shown.

[0084] Figure 7 shows another type of single-segment heating element 400, which also has the cutout 404 shown in Figure 6. This heating element has specially constructed terminals 401A and 401B. Terminal 401A has one type of extension 403, and terminal 401B has another type of extension 405. Each terminal 401A and 401B has an opening 407. The extensions can be folded along line XX. This folded extension can be used for mechanical attachment of the heating element using the opening 407. The shapes of the extensions 403 and 405 can position the opening 407 in different locations during folding to accommodate variations in mechanical attachment requirements.

[0085] Additionally, when the heating elements 400 have the necessary thickness and sufficient strength, they can be supported by the extensions once folded. Therefore, if needed, the heating elements 400 can stand upright for specific heating applications.

[0086] It should also be noted that, with Figure 4Compared to the cuts shown, cuts 305 and 404 have different shapes. Cut 305 in Figure 6 is shown enlarged in Figure 8. Cut 305 is flatter, with rounded ends 307, flat side portions 309, and grooves 311 separating a pair of side portions 309. Each groove 311 is created by the progression of each heating section portion 313, and by forming adjacent cuts (not shown in Figure 8) in the pattern of cut 305. The flattened round shape of cut 305 in Figure 6 is different from... Figure 4 The elliptical shape of the cut 111, for example, includes the slotted shape of the cut 305, wherein the flat portion of the cut is opposite to the curved first and second walls of the cut 111.

[0087] Figure 9 A schematic diagram of another construction of the heating element of the present invention is shown, which is shaped like a handheld fan or extends in an arc. For example, Figure 9 The fan-shaped element in the heating element can span 120 degrees. This heating element is indicated by reference numeral 500 and includes terminals 501A and 501B, heating sections 503A-503F, although only the lateral outer end sections are given reference numerals. The heating element 500 also includes busbars 505A-505G.

[0088] Heating element 500 can be combined with other heating elements to create a larger heating element area. Although Figure 9 The fan-shaped element shown is approximately 120 degrees in span, but other spans can also be used. Furthermore, if two heating elements are placed side-by-side, the heating element span can be 240 degrees; see [link to relevant documentation]. Figure 10A Furthermore, if three heating elements 500 are used, a ring-shaped structure can be formed, as shown in Figure 10b. This heating element design also demonstrates that heating element segments can be constructed in different shapes to suit specific heating requirements.

[0089] Once powered on, the heating element of this invention can be used to heat any kind of space. Examples of applications for the heating element include clothes dryers, particularly for... Figure 9 Examples of heaters include dishwasher pump heaters, and other heater applications such as test tube heaters, hot plate heaters, miniature air heaters, small igniters, box heaters, flow-through fluid heaters, radiant process and baking heaters, heaters for furnaces and ovens, heating radiators, storage heaters, fuel oil and fuel heaters, glow plugs, irons and ironing heaters, water heaters, plastic molding heaters, soldering irons, hair dryers, and hand dryers. It should be understood that these are merely examples of heaters in which the heating element of the present invention can be used, and the uses of the heating element of the present invention are not limited to the disclosed examples.

[0090] Although the cutout is shown as an oval or flattened circle, other shapes may be used, as long as the shape provides the required resistance heating for the given heating element.

[0091] Another embodiment of the invention relates to a heating element capable of providing two or more regions with different surface temperatures. Utilizing this feature, the heating element can be configured to provide heating at different temperatures for a specific application; for example, one region of the heating element operates at a higher temperature than another region.

[0092] In this embodiment, the heating element is conceived to consist of a plurality of wire bundles, each having a certain length, and these wire bundles forming a rhombus, which is part of the heating element. From the viewpoint of length and width, the rhombuses are joined together to form the heating element.

[0093] Figures 11a-11d An example of a wire harness and rhombus shape used for a heating element is shown. Figure 11a A single wire harness 601 is shown. Figure 11b shows two wire harnesses combined together to form a rhombus 603. When additional wire harnesses, totaling three, are added, as shown in Figure 11c, 1.5 rhombuses are formed. Figure 11d The diagram shows two rhombuses 603 formed by using four wire harnesses.

[0094] Using this configuration and controlling the wire harness dimensions, heating elements can be manufactured using monolithic resistive material, and the circuit traces of the sheet can be intentionally designed so that different areas of the sheet or heating element operate at different surface temperatures under the same operating conditions for the heating element. This capability allows the heating element to be designed to vary the surface temperature along the length of the circuit as needed. The sheet is based on the combination of the aforementioned wire harness and rhombuses. It should be understood that the number of wire harnesses and rhombuses is limited only by the heating application required for the heating element.

[0095] Figure 12 This is an example of heating element 605. This heating element has numerous wire bundles and full or half rhombuses. A full rhombus is shown as 607, and a half rhombus as 609. The rhombuses form the circuit traces of the heating element, along which current flows when a specific voltage is applied. Under a given applied voltage, Figure 12 The circuit traces shown can be made from a single sheet, which allows for the extension of the traces to increase the current path and produce more or less total resistance and wattage.

[0096] for Figure 12In the case of heating element 605, when considering the surface temperature of such a heating element, it is understood that certain areas of the final sheet may operate cooler than other areas. For heating element 605, the area consisting of more material (designated 611) will be used to cool a portion of the end of the trace 613 of the heating element, and the area of ​​the trace designated by 615 will become hotter.

[0097] As mentioned above, it can be modified as follows: Figure 12 The heating element shown is configured to vary the surface temperature of the heating element along the length of the trace. Figure 13a and Figure 13b An exemplary trace is shown, which is designed to provide a desired surface temperature difference for the heating element. Figure 13a Trace 617 is shown. Figure 13b Trace 617 is shown, and both are made of the same heating element resistive material with a defined thickness. Trace 617 consists of 6 rhombuses, and trace 619 consists of 5 rhombuses. Figure 13a and 13b The dimensions of each trace 617 and 619 are also shown. More specifically, the six-diamond trace 617 has a diamond width of 0.591 inches, which is larger than the 0.586-inch width of the five-diamond trace 619. The bundle width of the six-diamond trace 617 (0.036 inches) is also larger than that of the five-diamond trace 619 (0.030 inches). The six-diamond trace 617 also has a longer length (2.346 inches) compared to the five-diamond trace 619 (1.955 inches). In some respects, trace 619 is larger than trace 617. The inner width of the diamond in trace 619 is 0.526 inches, while the width of trace 617 is 0.520 inches. The inner length of the diamond in trace 619 is 0.166 inches, which is larger than the inner length of trace 617 (0.160 inches). It should also be noted that the rhombus heights of traces 617 and 619 are actually the same, or 0.391 inches. This means that combining different rhombuses, as described below, will result in only a slight change in the overall appearance of the heating element.

[0098] Due to the difference in size and material quantity resulting from using 6 rhombuses versus 5 rhombuses, the two traces 617 and 619 have the same resistance (ohms). At the same resistance, if the same voltage is applied to each trace, each trace will produce the same wattage and the same current in amperes.

[0099] However, under these equal conditions, since circuit trace 619 has less total material than circuit trace 617 and operates at the same ampere rate, the surface temperature will be higher for the circuit trace with less material. For example, assuming each circuit trace shown here will operate at 10 watts at 2.875 volts, this will result in trace 619 operating at a surface temperature T2 under the same operating conditions, which is greater than the surface temperature T1 of trace 617.

[0100] Figure 14a and 14b It shows Figure 13a and 13b Variations of the illustrated embodiment. Here, in Figure 14a The diagram shows trace 621, which consists of two sub-traces 617 and has a total of 12 rhombuses. Figure 14b Trajectory 623 is shown, which consists of 10 rhombuses or two sub-trajectories 619. Trajectories 621 and 623 are used under operating conditions of 5.75 volts and 20 watts. In this design, each sub-trajectorie 617 in trace 621 will operate at temperature T1 compared to each sub-trajectorie 619 in trace 623 operating at temperature T2. T2 is greater than T1 because less material in trace 623 with 10 rhombuses competes with trace 621 with 12 rhombuses. (As combined...) Figure 13a and 13b As explained, the resistance values ​​of traces 621 and 623 are the same because they are simply combinations of sub-traces 617 and 619, respectively.

[0101] As shown above, both traces 621 and 623 can operate at 20 watts at 575 volts, and it is further determined that the trace with less material (i.e., trace 623) will produce a higher surface temperature due to material content. Modifying this trace design by combining sub-traces 617 and 619 into a single trace can provide heating elements operating at two different surface temperatures. This is in Figure 15 As shown, a new trace 625 is provided, in which a sub-trace 617 with six rhombuses is paired with a sub-trace 619 with five rhombuses. This trace will generate 20 watts of heat at 5.75 volts, but a portion of the circuit trace will operate at a surface temperature T1, which is lower than the surface temperature T2 at which the other portion operates, because there is less material in that portion of the trace.

[0102] The trace 625 is just one example of a heating element design that will have different surface temperatures and therefore different heating effects for the desired application. Figure 16 This is another example of multiple traces combined together to provide a variety of different surface temperatures for circuit traces. Figure 16In the figure, the trace is indicated by reference numeral 627. The trace consists of multiple sub-traces. Viewed from top to bottom, trace 627 provides a first sub-traces 629 composed of two rhombuses. A second sub-traces 631, also composed of two rhombuses, is added to the first sub-traces 629. A third sub-traces 633, made of a single rhombus, is added to the second sub-traces 631. A fourth rhombus sub-traces 635 and a fifth rhombus sub-traces 637 are provided after the third sub-traces 633. Two additional sixth rhombus sub-traces 639 and a seventh rhombus sub-traces 641 are provided after the fifth sub-traces. Adjacent sub-traces can be designed such that there are different surface temperatures between adjacent traces. For example, sub-traces 629 and 631 can be designed to have the same resistance but less material in sub-traces 631, such that the surface temperature T2 of sub-traces 633 is greater than the surface temperature T1 of sub-traces 631. Therefore, sub-trace 635 with a diamond shape will be hotter than sub-trace 633, and surface temperature T3 will be greater than surface temperature T2. The remaining sub-traces 635, 637, 639, and 641 can be designed to increase surface temperatures in an orderly manner. However, sub-traces can also be designed using material quantities and resistance so that, in heating applications requiring such temperature variations, the surface temperature can decrease from a specific sub-trace or fluctuate between lower and higher surface temperatures.

[0103] although Figure 16 The rhombus shape remains essentially unchanged, while the number, linewidth, and width of the rhombuses in the sub-tracks may vary. However, the shape of the rhombuses may also change along the length of the track, resulting in different surface temperature effects. Figure 17 This embodiment is shown in the heating element, indicated by reference numeral 643, and has a conical shape. The shape of this heating element is similar to that shown above. Figure 9 The shape shown has a contour that varies along its length. Figure 17The diagram shows seven traces constituting the heating element, identified by reference numeral 645. Trace 645 is composed of a plurality of rhombuses, the size of which decreases towards the narrower diameter portion of the heater. Thus, rhombus 647 is larger than rhombus 649, and rhombus 649 is larger than rhombus 651. Along the length of trace 645, the length of material within the trace decreases, such that as the conical region gradually shrinks to its smaller end, the heating element will provide fewer watts to that smaller surface area. If the element wiring is designed equally, the portion of the trace with fewer watts will be suitable for a smaller surface area, thus the density of watts added to the shape will be equal. In this way, the cone can therefore have a uniform surface temperature, even though the surface area decreases as the shape gradually tapers. Furthermore, as previously described in detail, the design of the traces can be varied to change the element temperature along their length. In this way, the density of heat added to the conical surface can be made unequal, thus making the temperature of the conical surface non-uniform, and therefore the temperature of the conical surface can be variably controlled by the trace design. This control may be necessary when heat loss is uneven during application operation.

[0104] When considering the terminal portion of the heating element, another aspect of the heating element of the present invention relates to improving the performance of the heating element. Figure 18a shows a type of heating element, indicated by reference numeral 653. This heating element includes a trace 655 and a terminal end 657, with a wire harness width of 0.125 inches. With this wire harness width, the width of the joint 659 between the terminal end 657 and the trace 655 is 0.250 inches. In Figure 18b, the heating element indicated by reference numeral 661 has a trace 663 and a terminal end 665. The trace 663 has the same wire harness width as in Figure 18a, i.e., 0.125 inches. However, unlike the 0.250-inch thickness of the joint 659 in the heating element of Figure 18a, the thickness of the joint 667 between the terminal end 663 and the trace 661 is 0.375 inches. In this way, the additional material at the joint 667 cools this portion of the heating element and reduces any problem of excessive heat being received by the terminal portion of the heating element.

[0105] It should be understood that the diamond shape shown above is merely an example of a trace circuit used to achieve variable surface temperature functionality. Figures 19a-19e show different embodiments of the traces for the heating element. Figure 19a shows a heating element 671 with a slot, without the outwardly flared central portion of the diamond shape shown in Figure 18b. Figure 19b shows another heating element 673 with traces 675 comprising elongated portions 677, each portion disposed between a power connector 679 and a terminal end 681. Figure 19c shows yet another heating element 683, where the traces 685 consist of circular portions 687. These extend between the terminal ends 689. Figure 19d shows another heating element 691, where the traces 693 consist of multiple portions 695, wherein for each portion 695, the wire harness forms a U-shape and an inverted U-shape, with a single connector 697 in between. Figure 19e is a variation of the cross-sectional shape of Figure 19d, in which, for the heating element 699, instead of using a single connector for a pair of wire harnesses for both cross-sectional shapes, separate wire harnesses 700 and 701 are used to connect the U-shaped portion of the cross-section to the inverted U-shaped portion of the cross-section.

[0106] Figures 20a and 20b depict further examples of rhombuses of different shapes in the traces of the heating element. In Figure 20a, the heating element, indicated by reference numeral 703, has a trace 704 and rhombuses 705 and 707. Rhombus 705 represents the lower ohmic portion of trace 704, while rhombus 707 represents the higher ohmic portion of trace 704. Figure 20b shows a variation on the heating element of Figure 20a, indicated by reference numeral 709, in which a pair of traces 704 are used with four wire bundles 711, 713, 715, and 717.

[0107] As shown in Figures 20a and 20b, the actual “diamond” shape can be made larger or smaller as needed. This variation allows current to flow along a longer path desired by the designer. Depending on the application requirements, this effect will induce Joule heating in specific areas. For the heating elements of Figures 20a and 20b, the trace resistance value increases per unit trace length in areas with longer wire bundles. However, the actual individual wire bundle resistance per trace length remains constant; that is, for Figure 20b, the resistance per wire bundle length of each of the wire bundles 711, 713, 715, and 717 is equal. For the heating elements in Figures 20a and 20b, the lower ohmic portion will operate at a lower total wattage than the higher ohmic portion, thus providing the ability to deliver different levels of heat for a given trace.

[0108] For general heating elements, it is known that manufacturing these heating elements using the extended metal technique described above is a more efficient use of the heating element's resistive material. However, as mentioned above, this technique also introduces problems such as cracking at the junctions of the wire harness and the resulting uneven heating. From a material usage point of view, forming heating elements using stamping, photolithography, or other similar techniques is less efficient than these various extended metal heating elements, but these heating elements do not have the cracking problems inherent in extended metal heating elements.

[0109] By fabricating smaller trace circuits and connecting them together using jumpers or other connecting devices, the problem of having to use more material when manufacturing heating elements without extending the metal can be alleviated. (See now for reference.) Figure 21 The heating element, indicated by reference numeral 719, consists of four separate circuit traces, each identified as 721. Each trace has terminal ends 723 and 725. The heating element 719 includes three jumpers 727, 729, and 731. Jumper 727 connects the first trace to the second trace. Jumper 729 connects the second trace to the third trace, and jumper 729 connects the third trace to the fourth trace. With this configuration, much less material is wasted from the heating element's resistive material, as the jumpers only need to be made of conductive material, rather than the material used for resistance heating. Although four-trace circuits are shown, any number of circuits and circuit configurations can be used in this heating element design.

[0110] Figure 21 The heating element also allows voltage to be applied at different locations. Figures 22a and 22b illustrate embodiments of this. In Figure 22a, the heating element 733 has two traces 735 and 737 and a jumper wire 739. Voltage can be applied to trace 735 by connecting L1 and L2 to terminals 741 and 743 of the heating element 733, with only trace 735 used for heating. In Figure 22b, voltage is applied to terminal 741 of each of traces 735 and 737, such that both traces are used for heating.

[0111] Figures 23a and 23b illustrate another embodiment of the heating element construction. Figure 23a shows a single-trace heating element 745 having traces 747, terminals 749 and 751, and a power connector 753. The power connector 753 divides trace 747 into two trace portions 748 and 750. Figure 23b shows a three-trace heating element having the same type of power connector 753 as shown in Figure 23a, and similarly, each trace has a trace portion 756 separated by the power connector 753. The heating element 755 links the traces together using bus connectors 757 and 759. Using multiple power connectors, many different heating levels can be provided. For example, one or two trace portions from Figure 23a can be used. Similarly, one to all six portions of the three traces shown in Figure 23b can be used and connected to the terminals or power connectors that separate the trace portions using appropriate power connectors. Furthermore, the point defined as the power connector 753 can be used to attach the element to some object or surface to be heated. When the component is secured in position 753, it will be held more firmly during heating and thermal expansion. This additional securing, as a thermal expansion control fastener, can prevent excessive movement of the component at high temperatures, where thermal expansion could become a problem.

[0112] The heating element of this invention can be used in combination with an insulator in different ways, the insulator forming part of the heater structure to provide different types of heat. Figure 24a In section -b, it is shown that fasteners 765 are used to secure the foil heater trace 761 to the mica plate 763 (or other insulator). Figure 24a The top view is shown, and Figure 24b A side view is shown. With the heater trace 761 mounted on one side of the mica plate 763, the heater trace provides radiant heat in the direction indicated by the arrow for the intended application.

[0113] Figure 25a -c shows another variation of the heating application of the heater trace, in a top view ( Figure 25a An exploded side view (Fig. 25b) and an assembled side view (Fig. 25c) are shown. In this embodiment, the heater trace 761 is sandwiched between two mica plates 763, all secured together using fasteners 765. Utilizing the heater trace 761, between the mica plates 763, the heating element functions as a conductive heater with hot surfaces 766 and 768, wherein an object placed on the outer surface of the top mica plate 763 will be conductively heated due to contact with the hot surface 766.

[0114] The heating element of the present invention can also be used as an air heating device, wherein heat transfer is achieved by convection rather than conduction or radiation. In this embodiment, as shown in Figures 26a-b, and again referring to the description of Figures 6 and 7 above, a heating element 767 with extensions 769 and 771 is shown. The extensions can be folded along line XX to form a vertical heater 772 as shown in Figure 26b. Here, the folded heater portions 769 and 771 are attached to a mica plate 773 to produce a vertical heater.

[0115] Another variation of the vertical heater is as follows: Figure 27a As shown in -c, and indicated by reference numeral 775 in the attached figure. Figure 27a The heater is shown in a partially disassembled state. Figure 27b shows a top view of one of the traces, and Figure 27c shows the assembled heater. In this embodiment, four heater traces are used with four mica plates, a base mica plate 789, and three separate mica plates 793, 795, and 797, along with 12 fasteners 791. Heater traces 777, 779, 781, and 783 each have extensions 785 and 787 to allow the heater traces to be secured to the base mica plate 789 using the fasteners 791. The heater traces are also connected to the other three separate mica plates 793, 795, and 797 using the fasteners 799. This configuration creates a small heater whose heater traces are spaced apart from the mica plates, for example, see gap 800 in Figure 27c. This lack of contact eliminates heat loss through conduction across the mica surface, and the heater can be used for convective heating as air travels in the direction shown in the figure. The heater also requires very little airflow to prevent visible radiant heat from being generated on the surface of the heater trace.

[0116] Another aspect of the invention is the ability to remove heater traces and form them in three dimensions to provide heating elements that are not just two-dimensional. Figure 28a and 28b An example of such a three-dimensional heater is shown, which has a flat heater trace 800, whose Figure 28a Terminals 801 and 803 are formed as follows Figure 28b The diagram shows a semi-circular construction or a rolled-up circle. The heater trace 800 can be of the type where the heater trace is designed to have two or more distinct surface temperatures, such that the heat provided in a three-dimensional shape varies along the length of the heater. Alternatively, the heater trace can resemble the heating element disclosed in Figure 6, where the heater trace will have a uniform surface temperature along its length.

[0117] Figure 28a and 28bAnother variation of the heater is to take two heater traces and connect them to form a cylindrical shape. Voltage can be applied to the unconnected ends of the heater traces to form a series circuit using two semi-circular heater traces. This cylindrical construction can be used as... Figure 29a -b shows a cylindrical heater, wherein the cylindrical heater is marked 810, and the heater 811 is located in an insulating medium 813, which is, for example, a ceramic insulator, potting compound, etc. Figure 29a A side view of the heater is shown, while Figure 29b A schematic cross-sectional view of the heater is shown. The trace will be connected at one end 814 using terminal 816, and the other end of the trace will be connected to a power source. With this configuration and the ability to control the surface temperature along the length of the trace, the heater can be inserted into a pipe and provide additional control over the heat distribution per unit length of the pipe. Figure 28a and 28b As in the previous embodiment, the heater trace will have the same surface temperature over its entire length or a varying surface temperature over its entire length.

[0118] Figure 30 Another embodiment of the invention is shown, which is related to Figure 29a The embodiment of -b is similar. In this embodiment, the heater is indicated by reference numeral 815. The heater includes an outer tube 817 and an inner tube 819, a heater trace 821, and a lead 823 extending through the outer tube 817. The heater trace 821 is held in place between the tubes using an insulating medium 825, such as a ceramic insulating material, potting compound, etc. The heater 815 can be used to heat the material flowing through the inner tube 819. (Similar to...) Figure 28a As with embodiments 28b, 29a and 29b, the heater trace can be a trace that provides a uniform surface temperature over its varying surface length, with the surface temperature varying with the length.

[0119] exist Figure 31a -b illustrates yet another three-dimensional heater embodiment using heater traces. In these figures, the heater is indicated by reference numeral 827. Figure 31a Showing the main view, Figure 31bA bottom view is shown. The heater includes a frame 829. An end 831 of the frame 829 has a flange to support a mica plate 833. A heater trace 835 is arranged and formed in a sinusoidal shape, with the heater trace 835 passing through an opening (not shown) in the central mica plate 833. Another mica plate, or a bottom mica plate 837, is provided to electrically isolate a portion of the heater trace 835 from the frame bottom 839. The terminal ends of the frame bottom 839, the mica plate 837, and the heater trace 835 are secured together at 841. This securing can be any type of fastener to provide electrical isolation between the frame bottom 839 and the heater trace, while leaving a clearance hole 843 through the frame bottom 839 to allow the heater trace 835 to be connected to a power source for heating purposes. This embodiment is ideally suited for use along... Figure 31b The airflow direction shown is used to heat the airflow. In this design, the heater trace surface can be shaped and rotated to achieve dimensional stability and can be compactly formed in a small space, which is difficult to achieve in existing designs.

[0120] exist Figure 32a-3 4c illustrates other embodiments of the invention. These embodiments relate to the concept of avoiding the need to pre-form circuit traces before manufacturing the heating element assembly. Figure 31a In option -b, pre-formed heating elements may be required for assembly into the support structure. Figure 32a-3 In 2c, it is not necessary to pre-form the heater trace portion because the construction of the heater trace portion allows the shape of the heater trace portion to be determined as part of the heater element assembly.

[0121] Figure 32a A heater trace 851 for use in a heater assembly is shown. The heater trace 851 includes a pair of heater trace portions 853. The heater trace 851 has two terminals 855 and a bus connector 857. A fastening portion 859 is provided in the middle of each heater trace portion 853. Each terminal 855 has an opening 861 for securing purposes. The fastening portion 859 also has openings 863, and the bus connector 857 has a pair of fastening openings 865.

[0122] Heater trace 851 in Figure 32a The image is shown lying flat, and arrow 867 indicates the preferred airflow direction that will flow through the trace 851 when it is in the heater assembly during heating.

[0123] Figures 32b and 32c show the heater trace 851 in its assembled state with the mica support plate 869. Figure 32c shows a bottom view of the support plate 869. More specifically, the heater trace is formed into a sinusoidal shape by fastening the terminals 855, fastening portions 859, 863, and bus connector 857 to the mica plate at points 871a-e. That is, due to the positioning of the fasteners on the mica support plate 869, the shape of the heater trace naturally extends outward from the mica support plate 869 due to the fastening process. This self-forming shape eliminates the need to pre-form the heater trace 851 before installation.

[0124] In this configuration, the moving fluid can flow over the heater surface of the trace in order to maximize the heat absorbed from the surface and transfer it to the moving fluid. Flow is optimal if it flows parallel to the width of the heater trace to best prevent the heater trace from heating itself.

[0125] Although Figure 32a The heater trace of -c is shown as having a pair of heater trace portions, but a single heater trace as shown in FIG. 6 can be used to form a three-dimensional heating element. In the embodiment of FIG. 6, terminals 301A and 301B will be fastened to a support plate whose length is less than that of the heater trace, such that the heater trace 300 is bent after being attached to the support plate using fasteners. That is, unlike the two curves shown in FIG. 32b, only one curve will appear. Other combinations of terminals, bus connectors, one or more support plates, and the number of heater trace portions can be combined to form various three-dimensional shapes. Similarly, although the relative shapes of the heater trace and the support plate differ in length, other shape differences between the heater trace and the support plate can be employed so that the fixing of the heater trace to the support plate will produce a three-dimensional shape different from the sinusoidal shape shown in FIG. 32b.

[0126] exist Figure 33a-3 It is shown in 3e Figure 32a-3 A variation of design 2c, and this heater assembly is indicated by reference numeral 875. Instead of using a single support plate like in Figure 32c, multiple support plates 877a, 877b, and 877c are provided. Each plate has a connecting feature 878, allowing the plates to be linked together to form a plate assembly larger than the individual support plates 877a-c. The plates 877a, 877b, and 877c shown have an exemplary length of 0.875 inches.

[0127] exist Figure 33b The image shows heater trace 851 secured to each support plate 877a-c when in a flat state. Figure 33cPlates 877a-c, held in a spaced-out arrangement by fasteners 879, are shown. The fasteners hold the plates in place to allow heater traces 851 to be secured to the plates.

[0128] Once the heater traces are secured to the board, connecting features 878 are used to join boards 877a-c together to form heater traces with their sinusoidal shape, as shown in Figures 33d and 33e. For the three 0.875-inch boards 887a, 877b, and 877c, the total length of the joined boards is 2.625 inches. The dimensions shown are for illustrative purposes only; other dimensions may be used. Using connecting features 878, which are part of boards 877a-877c, the boards can be joined together as if stitched together. Figure 1 The plates are snapped together. If reinforcement is required, additional base plates (not shown) that match or approximate the shape of the assembly plates can be used for further support. The flexibility of the heater traces makes it possible to eliminate any preforming steps and improves the manufacturing efficiency of the heater assembly. Although the connection features are shown as an opening in one plate and opposing convex connectors in adjacent plates, other shapes or configurations can be used to allow adjacent plates to be joined together.

[0129] Figures 34a-e illustrate another variation using a flat heater trace shaped as part of a heater assembly. Figure 34a shows a heater trace 879 having a terminal 881, a bus connector 883, and a pair of intermediate portions 885. A central support plate 887 is provided for this trace 879. The central support plate 887 has two slots 889, each slot 889 being designed to mate with each intermediate portion 885 of the trace 879. More specifically, each intermediate portion has a slot (not shown) sized to accommodate each tab 891 within the slot 889 of the central support plate 887. The central support plate 887 itself is shown on the right side of Figure 34a and is also attached to the intermediate portions 885.

[0130] Referring now to Figure 34b, the central support plate 887 also has a pair of mounting brackets 893 disposed at the ends of the central support plate 887, the top and side views of which are shown in the circled diagram. A pair of support plates 895 are provided, each having a fastening portion 897 designed to engage with openings 899 in the terminals 881 and the bus connector 883. Once the support plates 895 are fastened to the terminals 881 and the bus connector 883, the heater assembly 900 is in a flat position, as shown in Figure 34c.

[0131] The support plate 895 is then moved so that the heater trace 879 bends, and the ends of the plate 895 are arranged to face each other at the joint 902. This configuration is shown in Figure 34d, and the heater trace has a C-shaped cross-sectional profile.

[0132] After moving the support plate 895 to the adjacency shown in Figure 34d, the mounting bracket 893 is fixed using the opening 901 in the support plate 895 to form a fully assembled heater 900.

[0133] The final shape of heater trace 879 is complex, achievable only through the flexibility of the heater trace and the ability to form that shape using fastening steps that connect all heater components together. Figure 32a-3 As with other embodiments of 4e, complex assembled heaters can be manufactured efficiently without requiring a heater trace pre-forming step. That is, the component shown in Figure 34c is laid flat and only its complex shape is used, with the steps of connecting plates 895 using mounting brackets 893. The mounting bracket is just one example of how plates 895 can be joined together, and another example is also possible. Other methods can also be used. For example, plates 895 can first be joined together at 902, and then a central support plate 887 is attached. In any case, as... Figure 32a-3 As shown in 4e, using heater traces can significantly save manufacturing time, thereby reducing the cost of heater assemblies.

[0134] The various embodiments described above are provided by way of illustration only and should not be construed as limiting the appended claims.

[0135] Those skilled in the art will readily recognize that various modifications and changes may be made without following the exemplary embodiments and applications shown and described herein, and without departing from the true spirit and scope of the appended claims.

Claims

1. A heating element, comprising: First terminal and second terminal; and At least one heating element segment extending between the first terminal and the second terminal, each heating element segment having a plurality of cuts arranged in a repeating pattern, each cut having an elliptical or oval shape; The first terminal and the second terminal, as well as the at least one heating element segment, are continuous single sheets. At least one of the first terminal and the second terminal includes an extension that extends from at least one of the first terminal and the second terminal and terminates at a free end. A fold line is provided between the free end of the extension and at least one of the first terminal and the second terminal, the fold line facilitating the folding of the extension relative to the heating element.

2. The heating element according to claim 1, wherein, Each of the first terminal and the second terminal includes the extension portion, with the heating element standing upright individually on the folded extension portion.

3. The heating element according to claim 1, comprising a plurality of heating element segments extending in an arc shape.

4. The heating element according to claim 1, comprising a plurality of heating element segments, wherein the plurality of heating element segments are formed in an arc shape or a circle.

5. A heating method, comprising: a) Providing a heating element according to claim 1 in space, and b) Power is supplied to the heating element to heat the space.

6. A heating element comprising: At least the first terminal and the second terminal; and At least one heating element segment extending between the at least first terminal and the second terminal, the at least one heating element segment having a circuit trace comprising at least a first portion and a second portion, the at least first portion and the second portion being configured to have different dimensions from each other, such that when a voltage is applied between the at least first terminal and the second terminal, there is a surface temperature difference between the at least first portion and the second portion of the at least one heating element segment.

7. The heating element according to claim 6, wherein, The at least one heating element segment has a three-dimensional shape.

8. The heating element according to claim 7, wherein, The three-dimensional shape is one of a semi-cylindrical shape, a cylindrical shape, and a sinusoidal shape.

9. The heating element of claim 6, further comprising at least one power connector or thermal expansion control fastener location disposed between the at least first portion and the second portion of the circuit trace.

10. The heating element according to claim 6, wherein, The circuit trace has a plurality of first rhombuses and a plurality of second rhombuses, wherein the plurality of first rhombuses are configured such that their resistance is less than that of the plurality of second rhombuses.

11. The heating element according to claim 6, wherein, The circuit trace has a plurality of rhombuses, and the width of the plurality of rhombuses gradually narrows continuously between the at least first terminal and the second terminal, or the width of one or more of the plurality of rhombuses varies along the length of the circuit trace.

12. The heating element according to claim 6, wherein, The circuit trace has a plurality of rhombuses, each rhombus having a wire harness width, and the width of the connection between at least one of the first terminal and the second terminal and the rhombus adjacent to at least one of the first terminal and the second terminal is greater than the wire harness width.

13. The heating element according to claim 6, wherein, The circuit trace includes at least a first set of rhombuses having resistance and a first shape and a second set of rhombuses having said resistance and a second shape, the second shape being different from the first shape and having a smaller mass than the first shape, and the second set of rhombuses operating at a surface temperature higher than the surface temperature of the first set of rhombuses when a voltage is applied to the circuit trace.

14. The heating element according to claim 13, wherein, The shape difference is based on one of the following: the width of the rhombus of the circuit trace, the width of the rhombus, the number of a set of rhombuses, or the internal width or height spacing between the wire bundles forming the rhombuses.

15. A heating element assembly, comprising: The heating element according to claim 6 includes a plurality of heating element segments and at least one jumper wire connecting the plurality of heating element segments together at least the first terminals.

16. A heater having a heating element, comprising: At least the first terminal and the second terminal; and At least one heating element segment extending between at least one first terminal and a second terminal, the at least one heating element segment having a circuit trace comprising at least one first portion and a second portion, the at least one first portion and the second portion being configured to have different dimensions from each other, such that when a voltage is applied between the at least one first terminal and the second terminal, there exists a surface temperature difference between the at least one first portion and the second portion of the at least one heating element segment; wherein the heating element has a cylindrical shape and the heating element is disposed in an insulating medium for heating, or the insulating medium is located between an inner tube and an outer tube for heating material flowing through the inner tube.

17. A three-dimensional heating element, comprising: At least one support plate; At least one heater trace having at least a first terminal and a second terminal, the heater trace having opposing first and second surfaces and cutouts formed thereon, the shape of the heater trace differing from the shape of the at least one support plate. Fasteners for connecting at least a first terminal and a second terminal to the at least one support plate at a first fastening position and a second fastening position, such that the heater trace forms a three-dimensional shape, thereby forming an attachment between the first terminal and the second terminal and the first fastening position and the second fastening position on the at least one support plate.

18. The three-dimensional heating element according to claim 17, wherein, The shape difference also includes the fact that the length of the heater trace is greater than the length of the at least one support plate.

19. The three-dimensional heating element according to claim 17, wherein, The heater trace includes a pair of heater trace portions connected at one end by a bus connector, and each heater trace portion has a terminal at its other end, the bus connector and the terminal being fixed to at least one support plate.

20. The three-dimensional heating element of claim 17, comprising at least two support plates, one end of the heater trace being fastened to one of the at least two support plates, and the other end of the heater trace being fastened to the other of the at least two support plates, the at least two support plates being fastened together to form the three-dimensional heating element.

21. The three-dimensional heating element according to claim 20, further comprising: A central support plate is attached to the heater trace at its midpoint, and the central support plate is also attached to the at least two support plates to further change the shape of the heater trace when the at least two support plates are fastened together.

Images