Diffuser component

Abstract

A diffuser includes an accordion-type material arranged in a ring. The accordion material includes a series of axially extending fins. Each fin extends between peaks and valleys of the accordion material, and the peaks and valleys are curved in a circumferential direction with respect to a central axis of the diffuser. A motor assembly including the diffuser is also disclosed.

Description

Background Technology

[0001] Diffusers are commonly used in fluid flow applications to change the direction of fluid flow. Diffusers are typically found at the inlet or outlet of motor-driven fans or blowers. Known diffusers generally have multiple guide vanes supported between a central axis and surrounding external supports. Summary of the Invention

[0002] The present invention provides a diffuser comprising an accordion-shaped material arranged in a ring and having a central axis, wherein the accordion-shaped material includes a series of axially extending fins, each fin extending between peaks and valleys of the accordion-shaped material, and wherein the peaks and valleys are curved in a circumferential direction relative to the central axis of the diffuser. The ring shape of the accordion-shaped material is advantageous because the diffuser can be positioned around other items, thereby providing encapsulation efficiency.

[0003] Alternatively, when viewed from one end of the diffuser, the peaks and valleys of the accordion-shaped material are inclined in opposite circumferential directions. This arrangement is useful for changing the direction of fluid flow.

[0004] When viewed from one end of the diffuser, each peak of the accordion-shaped material may optionally have a first side and a second side, wherein: each fin on each first side of each peak has the same size and / or geometry as each other; each fin on each second side of each peak has the same size and / or geometry as each other; and the fin on the first side of the peak has a different size and / or geometry than the fin on the second side of the peak.

[0005] The fins may have a curved radial profile. In one example, each peak and / or valley includes a curved circumferential profile or a pointed circumferential profile.

[0006] Alternatively, the accordion-like material can be located within the tubular surround. Surrounding the diffuser with a tubular member can reduce stress at the joints of the accordion-like material. The accordion-like material can optionally surround the tubular member.

[0007] A diffuser can be configured to heat the fluid flow as it passes through it during use. This is advantageous because the diffuser can serve the dual purpose of heating and diffusing the fluid flow.

[0008] In one example, the diffuser includes an induction coil located within or around an accordion-like material. If the diffuser is made of metal, this allows it to be used as an induction heating element.

[0009] In another aspect, the present invention provides a motor assembly including a diffuser as described above. Attached Figure Description

[0010] Figure 1A A schematic diagram of a scraper is shown;

[0011] Figure 1B It shows the use of Figure 1A A schematic diagram of the first process steps of a scraper;

[0012] Figure 1C It shows the use of Figure 1A A schematic diagram of the second process steps of the scraper;

[0013] Figure 1D It shows the use of Figure 1A A schematic diagram of the third process step of the scraper;

[0014] Figure 2A A schematic diagram of the first process step in an alternative scraping operation is shown;

[0015] Figure 2B A schematic diagram of the second process step that replaces the scraping operation is shown;

[0016] Figure 2C A schematic diagram of the third process step that replaces the scraping operation is shown;

[0017] Figure 2D A schematic diagram of the fourth process step that replaces the scraping operation is shown;

[0018] Figure 2E A schematic diagram of the fifth process step, which replaces the scraping operation, is shown;

[0019] Figure 2F A schematic diagram of the sixth process step, which replaces the scraping operation, is shown;

[0020] Figure 2G A schematic diagram of the seventh process step, which replaces the scraping operation, is shown;

[0021] Figure 3 It shows the way Figures 2A to 2G A schematic diagram of a scraping component made using an alternative scraping operation;

[0022] Figure 4 A schematic diagram of an alternative scraper is shown;

[0023] Figure 5 A schematic diagram of an alternative configuration for the cutting element is shown;

[0024] Figure 8A A schematic diagram showing the fin profile of the scraping component is provided;

[0025] Figure 8B A schematic diagram of the fin profile of the alternative scraping component is shown;

[0026] Figure 8CA schematic diagram of the fin profile of another alternative scraping component is shown;

[0027] Figure 6A A schematic diagram of the cutting component configuration is shown, in which the tip angle varies along the length of the cutting component;

[0028] Figure 6B A schematic diagram of an alternative cutting element configuration is shown, in which the tip angle varies along the length of the cutting element;

[0029] Figure 6C A schematic diagram of another cutting element configuration is shown, in which the tip angle varies along the length of the cutting element;

[0030] Figure 6D A schematic diagram of yet another cutting component configuration is shown, in which the tip angle varies along the length of the cutting component;

[0031] Figure 7A A schematic diagram of the cut edge profile of a straight-edge cut component is shown;

[0032] Figure 7B A schematic diagram of the cut edge profile of a wavy edge cutter is shown;

[0033] Figure 7C A schematic diagram of the cut edge profile of a curved edge cutter is shown;

[0034] Figure 9A It shows something similar to Figure 6A A schematic diagram of the fin profile of the scraping component;

[0035] Figure 9B A schematic diagram of the fin profile of the alternative scraping component is shown;

[0036] Figure 9C A schematic diagram of the fin profile of another alternative scraping component is shown;

[0037] Figure 9D A schematic diagram of the fin profile of another alternative scraping component is shown;

[0038] Figure 9E A schematic diagram of the fin profile of yet another alternative scraping component is shown;

[0039] Figure 10 A schematic diagram of the process for manufacturing the ring-shaped component is shown;

[0040] Figure 11 A schematic diagram of a scraping component made from a curved-edge cutter is shown;

[0041] Figure 12 It shows the result of Figure 11 A schematic diagram of a ring-shaped article made from a scraping component;

[0042] Figure 13 A schematic diagram of multiple scraping components made using curved-edge cutting parts is shown; and

[0043] Figure 14 A schematic diagram of an alternative scraper is shown. Detailed Implementation

[0044] In the following description, all references to up, down, inside, outside, vertical, horizontal, etc., are made with reference to the orientation in the accompanying drawings. It should be understood that this is not intended to be restrictive, and any suitable orientation may be used in practice.

[0045] Figure 1A A schematic diagram of a scraper 10 is shown, which includes a fixing device 12 for holding a material blank 20 in place during scraping operations. In the illustrated embodiment, the fixing device 12 includes a first support 13a and a second support 13b, between which the material blank 20 is held. The scraper 10 includes a first cutting element 14a and a second cutting element 14b located on opposite sides of the material blank 20. An actuator (not shown) is provided to move the material blank 20 relative to the cutting elements 14a, 14b. In one example, the supports 13a, 13b include rolling supports that operate to gradually move the material blank 20 relative to the cutting elements 14a, 14b.

[0046] Figure 1A The scraper 10 is shown in its initial configuration just before the scraping operation begins. In this initial configuration, the material blank 20 is positioned at the starting position in the fixing device 12, but the scraping operation has not yet started.

[0047] Figure 1B The first process steps of the scraping operation are illustrated, wherein the actuator has moved the material blank 20 upward by a predetermined increment relative to the cutting elements 14a, 14b, and the first cutting element 14a has moved horizontally inward from its starting position to form a first cut 22 in the material blank 20. It should be understood that the material blank itself can move upward relative to the vertical position of the cutting elements 14a, 14b. Optionally or additionally, the cutting elements 14a, 14b can move downward relative to the material blank 20, which can remain stationary.

[0048] The formation of the first cut 22 results in the formation of a first material strip 23, which has a free edge 24 at its first end 25 but remains attached to the material blank 20 at its second end 26. The thickness of the material strip is determined by the relative incremental distance of the material blank's vertical movement relative to the cut pieces 14a, 14b.

[0049] Figure 1CThe second process step of the scraping operation is illustrated, wherein the first cutting element 14a has moved outward away from the material blank 20, the material blank 20 has again moved upward relative to the cutting elements 14a, 14b by a predetermined increment, and the second cutting element 14b has moved horizontally inward from its starting position to form a second cut 32 in the material blank 20. The formation of the second cut 32 results in the formation of a second material strip 33, which is connected at its first end 35 to the second end 26 of the first material strip 23 and remains attached to the material blank 20 at its second end 36.

[0050] Figure 1D The third step of the scraping operation is illustrated, wherein the second cutting element 14b has moved outward away from the material blank 20, the material blank 20 has again moved upward relative to the cutting elements 14a, 14b by a predetermined increment, and the first cutting element 14a has again moved horizontally inward to form a third cut 42 in the material blank 20. The formation of the third cut 42 results in the formation of a third material strip 43, which is connected at its first end 45 to the second end 36 of the second material strip 33 and remains attached to the material blank 20 at its second end 46.

[0051] Repeat the above about Figures 1A to 1D The described process involves interlacing a first plurality of cuts made by a first cutting element 14a with a second plurality of cuts made by a second cutting element 14b to form an accordion-shaped material 50. This process continues until the desired amount of material blank 20 has been cut. The resulting accordion-shaped material 50 is then removed from the scraper 10 for further processing. In one example, either cutting element 14a or 14b is used to cut the accordion-shaped material 50 from the material blank 20 by cutting the entire material blank 20. Lubricant or cooling fluid may be used during the scraping process if desired.

[0052] The first cutting element 14a and the second cutting element 14b are in Figure 1C and Figure 1D The diagram shows the material billet moving outwards from its position between processing steps, beyond what is shown in the image. Figure 1A The starting position shown is not required, and the cut pieces 14a and 14b can return to their starting position or another position, rather than going beyond their starting position.

[0053] In the aforementioned scraping operation, the cutting elements 14a and 14b move linearly toward and away from the material blank 20 in a reciprocating motion in a direction perpendicular to the direction of movement of the material blank 20 relative to the cutting elements 14a and 14b. This... Figures 1B to 1DThe horizontal movement of the cutting elements 14a and 14b is shown in the figure. It should be understood that this is not necessary, and the cutting elements 14a and 14b can move in a direction not perpendicular to the direction of movement of the material blank 20 relative to the cutting elements 14a and 14b.

[0054] Figures 2A to 2G A modified scraping operation is described, wherein the first cutter 14a and the second cutter 14b each perform two consecutive cuts in the material blank. Figure 2A and Figure 1B Similarly, the material blank 20 has been moved upward by a predetermined increment relative to the cutting elements 14a and 14b, and the first cutting element 14a has been moved horizontally inward from its starting position to form a first cut 122 in the material blank 20. The formation of the first cut 122 results in the formation of a first material strip 123, which has a free edge 124 at its first end 125 but remains attached to the material blank 20 at its second end 126.

[0055] Figure 2B The intermediate process step is shown, in which the first cutting element 14a has been moved outward away from the material blank to allow the material blank 20 to move upward relative to the cutting elements 14a, 14b by a predetermined increment. Figure 2C As shown, the first cutting member 14a then moves inward again to form a second cut 127, which results in the formation of a second material strip 128, which has a free edge 129 at its first end 130 but remains attached to the material blank 20 at its second end 131. The depth of the first cut 122 is greater than the depth of the second cut 127, such that the second material strip 128 forms a rib 174 on the scraping member (see...). Figure 3 ).

[0056] Now for reference Figure 2D The first cutting element 14a has moved outward away from the material blank 20, the material blank 20 has moved upward relative to the cutting elements 14a and 14b by a predetermined increment, and the second cutting element 14b has moved horizontally inward from its starting position to form a third cut 132 in the material blank 20. The formation of the third cut 132 results in the formation of a third material strip 133, which is connected at its first end 135 to the second end 126 of the first material strip 123 and remains attached to the material blank 20 at its second end 136. The second end 131 of the second material strip 128 is attached to the third material strip 133 at a point between the first end 135 and the second end 136 of the third material strip 133.

[0057] Figure 2EAnother intermediate process step is shown, in which the second cutting element 14b has been moved outward away from the material blank to allow the material blank 20 to move upward relative to the cutting elements 14a, 14b by a predetermined increment. Figure 2F As shown, the second cutting member 14b then moves inward again to form a fourth cut 147, which results in the formation of a fourth material strip 148, which has a free edge 149 at its first end 150 but remains attached to the material blank 20 at its second end 151. The depth of the third cut 132 is greater than the depth of the fourth cut 147, such that the fourth material strip 148 forms a rib 174 on the scraping member. Figure 3 ).

[0058] Now for reference Figure 2G The second cutting element 14b has moved outward away from the material blank 20, the material blank 20 has moved upward relative to the cutting elements 14a and 14b by a predetermined increment, and the first cutting element 14a has moved horizontally inward to form a fifth cut 162 in the material blank 20. The formation of the fifth cut 162 results in the formation of a fifth material strip 163, which is connected at its first end 165 to the second end 136 of the third material strip 133 and remains attached to the material blank 20 at its second end 166. The second end 151 of the fourth material strip 148 is attached to the fifth material strip 163 at a point between the first end 165 and the second end 166.

[0059] Repeat the above about Figures 2A to 2G The described process involves interlacing a first plurality of cuts made by the first cutting element 14a with a second plurality of cuts made by the second cutting element 14b. In particular, in this example, two consecutive cuts made by the first cutting element 14a and two consecutive cuts made by the second cutting element 14b are interlaced in a repeating series.

[0060] Figure 3 A schematic diagram of an accordion-shaped material 170 is shown, comprising a series of fins 171, each fin 171 extending between corresponding peaks 172 and valleys 173 of the accordion-shaped material 170, wherein each fin 171 has an associated rib 174. It should be understood from the above regarding... Figures 1A to 1D The process described produces an accordion-like material 50 with a similar configuration, but without any ribs 174.

[0061] The consecutive cuts formed in the material blank 20 by the same cutting element do not necessarily have to have different lengths, and in another example, the consecutive cuts formed by the same cutting element can have the same length. In another example, the number of consecutive cuts performed by each cutting element may be different, such that one cutting element can perform a first number of consecutive cuts on a first side of the material blank 20, while another cutting element can perform a different number of consecutive cuts on a second side of the material blank 20. In some examples, one cutting element performs a single cut before another cutting element performs a series of consecutive cuts.

[0062] Refer to the above Figures 1A to 1D and Figures 2A to 2G In the described example, the movement of cutting elements 14a and 14b is depicted such that only one of cutting elements 14a and 14b moves at any given time. This is not necessary, and the scraper 10 can be configured such that both cutting elements 14a and 14b are in motion for at least a portion of the operating time.

[0063] Figure 4 A schematic diagram of an alternative scraper 200 is shown, which is configured to simultaneously scrape multiple material blanks 20 to simultaneously produce multiple corresponding accordion-shaped materials 50. Scraper 210 is identical in all respects to scraper 10 described above, except that the fixing device 212 of scraper 210 is configured to hold the multiple material blanks 20 adjacent to each other, and the widths of the first and second cutting elements 214a, 214b are suitable for simultaneously cutting all material blanks 40, respectively. The first cutting element 214a and the second cutting element 214b each have a straight cutting edge 80, although this is not necessary, as will be described in more detail below.

[0064] Many different scraper configurations are possible. Figure 5 In one embodiment schematically shown, the dimensions of the first cutter 14a are different from those of the second cutter 14b, such that the tip angle θa is greater than the tip angle θb.

[0065] Figures 6A to 6D A schematic diagram of the cutting element configuration is shown, where the tip angle θ is along the length of the cutting element (entering as shown). Figures 6A to 6D The page shown has changed. Figure 6A In this configuration, the tip angle θ1 on the side of the cut piece closest to the observer (refer to the figure) is smaller than the tip angle θ2 on the side of the cut piece furthest from the observer. This configuration is... Figure 6B The tip angle θ2 is reversed, so that the tip angle θ2 at the side of the cut piece furthest from the observer (refer to the figure) is smaller than the tip angle θ1 at the side of the cut piece closest to the observer.

[0066] exist Figure 6CIn this configuration, the tip angle θ2 at the edge of the cut farthest from the observer (refer to the figure) is smaller than the tip angle θ1 at the edge of the cut closest to the observer. Furthermore, the cut edge 80 is angled, causing the horizontal range X (refer to the figure) of the cut to increase from X1 to X2 as it enters the page. This configuration... Figure 6D The inverse is reversed so that the tip angle θ1 at the edge of the cut closest to the observer (refer to the figure) is smaller than the tip angle θ2 at the edge of the cut furthest from the observer, and the horizontal range X of the cut (refer to the figure) decreases from X1 to X2 as it enters the page.

[0067] In another example, the horizontal range X of the cut piece can vary with the width of the cut piece, allowing the cut edge 80 to have any desired profile (when viewed from above), such as curved, stepped, wavy, etc. This can be applied to cut pieces with a fixed tip angle θ across the width of the cut piece, or to cut pieces with the above reference. Figures 6A to 6D Any variation of the cutter described. Furthermore, the profile of the material blank (when viewed from above) may optionally be machined to conform to the profile of the cutter. For example, a cutter with a concave curved cut edge 80 (when viewed from above) may be used to scrape a material blank with a convex curved profile (when viewed from above).

[0068] Figures 7A to 7C A schematic diagram showing different cut edge profiles is provided. For ambiguity, please refer to [reference needed]. Figure 1A For reference, the cut edge contour is the vertical variation of the cut edge when viewed inwards from the page. Figure 7A The cutting edge profile 580a shown is the cutting edge profile of a straight cut without vertical profile variation. Figure 4 An example of a straight cut edge profile 80 is shown. Figure 7B The wavy cut edge profile 580b is shown. Figure 7C The curved cut edge profile 580c is shown.

[0069] It should be understood that any of the above-mentioned cutting variations can be used in any combination as needed. Furthermore, cutting elements 14a and 14b do not necessarily need to be oriented in the horizontal plane (see reference). Figure 1A Furthermore, one or both of the cutting parts 14a and 14b can be oriented at a certain angle relative to the horizontal plane (see reference). Figure 1A ).

[0070] exist Figures 8A to 8C The diagram illustrates the effect of different tip angles on the cutting parts 14a and 14b. Figure 8AThe image shows an accordion-shaped material 350a produced by a scraper 10 having a first cutter 14a and a second cutter 14b with equal tip angles. The accordion-shaped material 350a includes a series of fins 371a, each fin 371a extending between corresponding peaks 372a and valleys 373a of the accordion-shaped material 350a. Figure 8A As shown, the peak 372a of the accordion-shaped material 350a points vertically upward, and the valley 373a of the accordion-shaped material 350a points vertically downward.

[0071] Figure 8B and Figure 8C Schematic diagrams of exemplary accordion-shaped materials 350b and 350c are shown, which can be produced by a scraper 10 having a first cutter 14a and a second cutter 14b having unequal tip angles. Figure 8B In the accordion-shaped material 350b, the peak 372b is inclined in the first direction 375, and the valley 373b of the accordion-shaped material 350b is inclined in the second direction 376. Figure 8C In the accordion-shaped material 350c, the peak 372c is inclined in the second direction 376, and the valley 373c of the accordion-shaped material 350c is inclined in the first direction 376.

[0072] Figures 9A to 9E A schematic diagram shows the effect of changing the cutting parameters of the cutting parts 14a and 14b on the profile of the accordion-type material fins (where the cutting parameters include cutting speed, depth and length). Figure 9A A fin 471a with a straight profile is shown, which is made by passing the cut pieces 14a, 14b through the material blank 40 using cutting parameters that do not change during the cutting duration. Figure 9B A fin 471b with a first curved profile is shown. This fin 471b is formed by passing cut pieces 14a and 14b through a material blank 40 using a first cutting parameter variation. Figure 9C A fin 471c with a second curved profile is shown, which is formed by passing cut pieces 14a, 14b through a material blank 40 using a second cutting parameter variation. A first cutting parameter variation produces a curved fin 471b, which results in peaks 472b and valleys 473b with sharp profiles, while a second cutting parameter variation produces a curved fin 471c, which results in peaks 472c and valleys 473c with more curved profiles.

[0073] Figure 9D and Figure 9E Another example of fin profiles achievable by changing the cutting parameters is shown. Figure 9DIn the process, variations in cutting parameters produce curved fins 471d, resulting in accordion folds with a shark fin-like profile. Figure 9E In the process, changes in cutting parameters produce bent fins 471e, which result in fins that are in contact with... Figure 9D Accordion pleats with a shark fin-like outline oriented in the opposite direction.

[0074] It should be understood that cutting parameter variations can be selected as needed for any specific cut, and the same cutting parameters need not be used for continuous cuts made from the same or different cutting elements. Furthermore, variations in cutting parameters can be used in combination with cutting elements of different sizes and / or geometries to achieve peak / valley "tilting" in conjunction with curved profile fins.

[0075] Figure 10 A method for forming an annular article from a material blank 20, which has been scraped into an accordion-shaped material 50 using any of the scraping methods described above, is shown. After the accordion-shaped material 50 is removed from the scraper 10, it is wound around a mandrel 500 such that the peaks 572 of the accordion-shaped material are radially outward of the valleys 573 of the accordion-shaped material. The two free ends of the accordion-shaped material are secured together by any suitable method, such as welding, brazing, or gluing, and the resulting annular article 550 is removed from the mandrel 500. It should be understood that if the accordion-shaped material 50 has been manufactured such that the peaks and valleys are inclined in opposite directions (e.g., ...), ... Figure 8B and 8C As shown), the peak of the annular item 550 will tilt in the first circumferential direction, while the valley will tilt in the other circumferential direction.

[0076] One example application of the ring-shaped article 550 is in the production of induction heating elements 560. For example... Figure 10 As shown, the annular article 550 is placed within a retainer 552, which is sized to hold the annular article 550 in a compressed state to reduce stress on the peaks and valleys of the annular article 550 and stress on the connections between the ends of the accordion-like material 50. An induction coil 554 is placed inside the annular article to generate the induction heating element 560. The annular article 550 being located within the retainer 552 is not necessary and can be omitted if desired. Furthermore, in any case, the induction coil 554 may surround the annular article 550 rather than being located within it.

[0077] The ring-shaped article 550, the induction coil 554, and the retainer 552 can be made from any suitable material. In one example, the ring-shaped article 550 includes stainless steel, aluminum, or copper. The accordion-like material 50 may be coated with an electromagnetic material, such as nickel or a nickel-chromium alloy, before or after it is formed into the ring-shaped article 550.

[0078] Figure 11 A schematic diagram of an accordion-shaped material 600 is shown, which has been manufactured using materials with curved edges (e.g., Figure 7C A pair of cut pieces (shown as curved edge 580c) are scraped from the material blank 20. As... Figure 11 As shown, the fins 671 of the accordion-shaped material 60 are curved. In one example, the material blank 20 is machined before the scraping process begins so that the top surface of the material blank 20 conforms to the shape of the cut piece.

[0079] Figure 12 An annular article 610 is shown, which is made of accordion-shaped material 600 wound around a mandrel, such that the peaks 672 of the accordion-shaped material are located radially outside the valleys 673 of the accordion-shaped material. Because the fins of the accordion-shaped material 600 are curved, when viewed along the axis from the indicated direction 617, the peaks 672 and valleys 673 of the annular article 610 are curved in a counterclockwise circumferential direction relative to the central axis 615 of the annular article 610.

[0080] The annular article 610 can be used as a diffuser 620 to change the flow direction of the fluid as it passes through the diffuser 620. If desired, the diffuser 620 can be placed within a retainer (not shown) sized to hold the diffuser 620 in a compressed state to reduce stress on the peaks 672, valleys 673, and the connection between the ends of the accordion-shaped material 600.

[0081] In another example, an induction coil (such as...) Figure 10 The induction coil 554 may be located within or around the diffuser 620 to form a diffuser capable of heating the fluid flow as the fluid flows through the diffuser 620. Such a diffusion induction heating element can be usefully used, for example, at the outlet of a motor-driven blower or fan.

[0082] In another example, a non-inductive method of heating the fluid flow through the diffuser 620 can be used, such as a resistance heating element, which can be configured to directly heat the fluid flow or to heat the material of the diffuser 620 such that heat is transferred to the fluid flow via the diffuser 620 when the fluid passes through the diffuser 620 in use.

[0083] Figure 13 A schematic diagram shows multiple accordion-style materials 600 arranged side by side. This arrangement can be achieved by using materials similar to... Figure 4The arrangement shown involves a pair of cutting blades scraping multiple material blanks 20 arranged side-by-side to produce a plurality of accordion-shaped materials 600. Each cutting blade has a wavy cut edge profile configured to cut curved strips of material from each material blank 20. Each accordion-shaped material 600 can then be further processed in any desired manner, including forming a diffusion 620.

[0084] It should be understood that all references to variations and substitutions in the dimensions, geometry, and uses of the cutting elements 14a and 14b described above also apply to cutting elements configured to simultaneously cut multiple material blanks 20 (e.g., Figure 4 Variations and substitutions in the size, geometry, and application of the cut parts 214a and 214b.

[0085] Figure 14 An alternative scraper 700 is shown, which includes a fixing device 712 for holding the material blank 720 in place during scraping operations. The fixing device 712 includes a fixing portion 713a and a rotating portion 713b to which the material blank 20 is attached. The scraper 700 includes a single cutting element 714.

[0086] During the scraping operation, the material blank is positioned correctly for a first cut on its first side 721. After the first cut, the cutter 714 is withdrawn from the material blank 20, and the material blank is rotated 180 degrees by the rotating portion 713b of the fixing device 712. A second cut is then made on the second side 722 of the material blank. This process is repeated until the desired amount of material blank 20 has been cut. The fixing device 712 can be used to increase the relative height of the material blank with respect to the cutter 714. Alternatively or additionally, the cutter 714 can be moved relative to the fixing device 712. Figure 13 The cutter 714 shown has a straight cut edge 780. However, it should be understood that the cut edge of the cutter 714 may have any suitable configuration, such as curved.

[0087] It should be understood that the material blank 20 can be cut from any series of directions. For example, the rotating portion 713b of the scraper 700 can rotate the material blank 20 in 90-degree increments, such that a first plurality of cuts are made from a first direction relative to the material blank, a second plurality of cuts are made from a second direction relative to the material blank, a third plurality of cuts are made from a third direction relative to the material blank, and a fourth plurality of cuts are made from a fourth direction relative to the material blank. In another embodiment, the material blank can be rotated 120 degrees, such that a first, second, and third plurality of cuts are made relative to the material blank 20 from different orientations. (Refer to above) Figures 1A to 1DThe described scraper 10 can also be used to cut from different orientations by providing a cutting element arranged in a desired orientation relative to the material blank 20.

[0088] It should be understood that regardless of the tip angle, cutting speed variation, cutting edge profile, or scraper type, any number of consecutive cuts can be made from the same workpiece to any desired depth. For example, as Figure 3 The accordion-style material with ribs 170 shown can be made from any shape of cut piece on any type of scraper described above.

Claims

1. A diffuser comprising an accordion material arranged in a ring and having a central axis, wherein the accordion material comprises a series of axially extending fins, wherein each fin extends between a peak and a valley of the accordion material, and wherein the peaks and valleys are curved in a circumferential direction relative to the central axis of the diffuser.

2. The diffuser of claim 1, wherein, The peaks and valleys of the accordion material are inclined in opposite circumferential directions when viewed from one end of the diffuser.

3. The diffuser of claim 1 or 2, wherein, Each peak of the accordion material has a first side and a second side when viewed from one end of the diffuser, wherein: Each fin located on each first side of each peak has the same size and / or geometry as each other; Each fin located on each second side of each peak has the same size and / or geometry as each other; and The fins located on the first side of a peak have a different size and / or geometry to the fins located on the second side of a peak.

4. The diffuser of any one of claims 1 to 3, wherein, The fins have a curved radial profile.

5. The diffuser of any one of claims 1 to 4, wherein, Each peak and / or valley comprises: a curved circumferential profile; or a pointed circumferential profile.

6. The diffuser of any one of claims 1 to 5, wherein, The accordion material is located within a tubular surround.

7. The diffuser of any one of claims 1 to 6, wherein, The accordion material surrounds a tubular member.

8. The diffuser of any one of claims 1 to 7, wherein, The diffuser is configured to heat a fluid flow when the fluid flow passes through the diffuser in use.

9. The diffuser of claim 8, comprising an induction coil located within or around the accordion material.

10. A motor assembly comprising the diffuser of any one of claims 1 to 9.

Images