A positioning device for welding a blade of an impeller of a mixed flow fan

Abstract

The present application relates to the technical field of impeller welding, and particularly relates to a positioning device for welding the blades of an impeller of a diagonal flow fan, comprising a plurality of circumferentially arrayed movable blades arranged on the outer side of an impeller cylinder, and a main wheel disc fixed on the inner side of the impeller cylinder, wherein the outer side of the impeller cylinder is provided with a positioning mechanism for limiting the installation position of the plurality of movable blades during welding, the positioning mechanism comprises an upper positioning plate and a lower positioning plate arranged in sequence and spaced apart from each other from top to bottom, and a supporting bottom plate arranged at the bottom of the lower positioning plate and in contact with the bottom of the impeller cylinder. The present application avoids the defects of laser scribing without rigid constraint or single-side positioning in the prior art, which causes the other side of the blade to be in a semi-free state, and simultaneously limits the spatial angle and three-dimensional position of the leading edge and trailing edge of the movable blade during welding, thereby ensuring the precision of the blade after welding and forming, guaranteeing the uniformity of the flow channel, improving the aerodynamic performance of the fan, and prolonging the fatigue service life.

Description

Technical Field

[0001] This invention relates to the field of impeller welding technology, and in particular to a positioning device for welding impeller blades of a mixed-flow fan. Background Technology

[0002] Mixed-flow fans are widely used in industrial ventilation, cooling, and heat exchange systems. As the core working component of a mixed-flow fan, the spatial position and forming precision of its blades directly determine the overall efficiency and operational stability of the machine. For mixed-flow fans, the leading edge (inlet side) and trailing edge (outlet side) of the welded impeller blades have strict spatial angle requirements, demanding extremely high positioning accuracy. Existing technologies use laser scribing on the impeller disc or single-sided (inlet or outlet side) positioning devices for blade positioning before welding. This method results in poor blade positioning accuracy, leading to welding deviations that affect the fan's aerodynamic performance and operational reliability, and may even shorten the fan's service life. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, the present invention provides a positioning device for welded impeller blades of a mixed-flow fan, which solves the problem that the blades are not accurately welded because the laser scribing has no rigid constraint or the single-sided positioning results in the other side of the blade being in a semi-free state.

[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A positioning device for welding impeller blades of a mixed-flow fan includes a plurality of circumferentially arrayed moving blades disposed on the outside of the impeller body, and a main impeller fixed on the inside of the impeller body. The outside of the impeller body is provided with a positioning mechanism for limiting the installation position of the impeller body and the plurality of moving blades during the welding process. The positioning mechanism includes an upper positioning plate and a lower positioning plate arranged at intervals from top to bottom, and a support base plate disposed at the bottom of the lower positioning plate and in contact with the bottom of the impeller body. The lower surface of the upper positioning plate is provided with a plurality of circumferentially arrayed upper slots, and the upper surface of the lower positioning plate is provided with a plurality of circumferentially arrayed lower slots. The support base plate is provided with a locking assembly for fixing the impeller body.

[0005] As a further optimization of the present invention, a limiting ring groove is provided on the lower positioning plate, and a limiting ring body fixed to the supporting base plate is detachably connected to the inner side of the limiting ring groove. A limiting ring matching the bottom of the impeller cylinder is fixed at the top center of the supporting base plate.

[0006] As a further optimization of the present invention, the upper and lower slots are staggered, the upper and lower sides of the moving blade are slidably connected to the upper and lower slots respectively, and one side of the moving blade is in contact with the outer wall of the impeller cylinder.

[0007] As a further optimization of the present invention, the locking assembly includes a positioning shaft disposed inside the impeller cylinder and an upper pressure plate sleeved on the top of the positioning shaft. A limiting groove is formed at the center of the main wheel, and a lower pressure plate matching the limiting groove is provided at the bottom of the upper pressure plate, and the lower pressure plate is movably sleeved with the positioning shaft.

[0008] As a further optimization of the present invention, the top of the upper pressure plate is provided with an anti-slip pad, the top of the positioning shaft is threadedly connected with a fastening nut whose bottom contacts the anti-slip pad, and the center of the support base plate is provided with a threaded hole that is threadedly connected to the bottom end of the positioning shaft.

[0009] As a further optimization of the present invention, the positioning mechanism further includes a connecting component disposed between the upper positioning plate and the lower positioning plate, the connecting component being used to fix the upper positioning plate and the lower positioning plate that are disposed at a fixed interval.

[0010] As a further optimization of the present invention, the connecting assembly includes several limiting shafts arranged in a circumferential array on the outside of the impeller cylinder, and several threaded holes II opened on the lower positioning plate. The bottom of the limiting shaft is threadedly connected to the threaded holes II, and the top of the limiting shaft passes through the upper positioning plate and is slidably connected to it. The top of the limiting shaft is threadedly connected to a fastening nut II.

[0011] By employing the above technical solution, the present invention provides a positioning device for welding impeller blades of a mixed-flow fan, which, compared with the prior art, has at least the following beneficial effects: 1. This invention utilizes interlocking upper and lower positioning plates with staggered upper and lower slots, allowing the upper and lower sides of the moving blade to slide and be limited within their respective slots. One side of the moving blade directly contacts the outer wall of the fixed impeller cylinder. This avoids the shortcomings of existing technologies where laser scribing lacks rigid constraints or single-sided positioning results in the other side of the blade being in a semi-free state. During welding, the spatial angle and three-dimensional position of the leading and trailing edges of the moving blade are simultaneously restricted, ensuring the accuracy of the welded blade, guaranteeing the uniformity of the flow channel, improving the aerodynamic performance of the fan, and extending its fatigue life.

[0012] 2. This invention, by setting a limiting ring at the center of the support base plate that matches the bottom of the impeller cylinder, and combining it with a locking assembly, uses a lower pressure plate precisely fitted into the limiting groove at the center of the main impeller shaft. Under the dual action of axial compression and radial limiting, the impeller cylinder and the main impeller are rigidly locked relative to the support base plate. This structure provides an absolutely stable, non-skewed central assembly reference for each moving blade distributed in the outer circumferential array, avoiding minor displacement of the impeller cylinder and ensuring the operational reliability of the entire positioning device.

[0013] 3. The positioning mechanism of this invention utilizes circumferentially distributed limiting shafts that penetrate the upper and lower positioning plates. Combined with the second fastening nut and the limiting ring and groove at the lower positioning plate, it achieves precise relative fixation of the upper and lower positioning plates in terms of axial spacing and circumferential angle. This design not only ensures that all staggered upper and lower slots are strictly anchored on the designed three-dimensional spatial coordinates, guaranteeing extremely high installation consistency among the circumferentially arrayed moving blades; simultaneously, this detachable mechanical plug-in and threaded connection structure based on the limiting shafts, slots, and limiting rings allows for rapid disassembly of the positioning fixture after welding, maintaining extremely high positioning accuracy while improving the efficiency of welding the impeller of the mixed-flow fan. Attached Figure Description

[0014] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a front sectional view of the present invention; Figure 3 This is a schematic diagram of the positioning mechanism of the present invention; Figure 4 This is a schematic diagram of the impeller blade structure of the present invention; Figure 5 This is an exploded view of the connecting component of the present invention; Figure 6 This is a schematic diagram of the locking assembly of the present invention; Figure 7 for Figure 2 A magnified structural diagram of part A.

[0015] In the diagram: 1. Impeller body; 2. Moving blades; 3. Main impeller disk; 4. Positioning mechanism; 41. Upper positioning plate; 42. Lower positioning plate; 43. Support base plate; 44. Limiting ring groove; 45. Limiting ring body; 46. Limiting ring; 47. Upper slot; 48. Lower slot; 49. Locking assembly; 491. Positioning shaft; 492. Upper pressure plate; 493. Limiting groove; 494. Lower pressure plate; 495. Anti-slip pad; 496. Fastening nut; 497. Threaded hole; 5. Connecting components; 51. Limiting shaft; 52. Threaded hole two; 53. Fastening nut two. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0017] Traditional impeller blade positioning devices suffer from poor blade positioning accuracy during the positioning and welding process, leading to blade welding deviations and consequently affecting the aerodynamic performance and operational reliability of the fan. To ensure the accuracy of the welded blades, improve the aerodynamic performance of the fan, and extend its fatigue life, [further details are needed]. Figure 1 - Figure 7 This invention provides a positioning device for welding impeller blades in a mixed-flow fan. The impeller to be welded includes an impeller body 1, a main impeller 3 fixed inside the impeller body 1, and several moving blades 2 arranged in a circumferential array on the outside of the impeller body 1. In order to implement high-precision spatial constraints on the above components during the welding process, this embodiment provides a positioning mechanism 4 on the outside of the impeller body 1 to limit its installation position relative to the several moving blades 2 during the welding process.

[0018] Specifically, the positioning mechanism 4 includes, in terms of spatial hierarchy, an upper positioning plate 41 and a lower positioning plate 42 arranged sequentially from top to bottom, and a support base plate 43 located at the bottom of the lower positioning plate 42 and in contact with the bottom of the impeller cylinder 1. In existing technologies for welding mixed-flow fan impellers, there is typically a lack of an absolutely rigid centering reference for the main impeller 3 and the impeller cylinder 1. This leads to the impeller body being prone to microscopic radial eccentricity or axial movement when the fixture applies force or undergoes welding thermal cycles, resulting in dynamic imbalance after overall forming. The support base plate 43 serves as the basic bearing surface of the entire tooling set, and a locking assembly 49 for fixing the impeller cylinder 1 is provided on it.

[0019] The locking assembly 49 specifically comprises: a positioning shaft 491 disposed inside the impeller cylinder 1, and an upper pressure plate 492 sleeved on the top of the positioning shaft 491. A limiting groove 493 is pre-formed at the axis of the main impeller 3, and a lower pressure plate 494 matching the limiting groove 493 is disposed at the bottom of the upper pressure plate 492, with the lower pressure plate 494 movably sleeved with the positioning shaft 491. To apply a tightening force, a threaded hole 497 is provided at the axis of the support base plate 43, threaded to the bottom end of the positioning shaft 491, and a fastening nut 496 is threaded to the top of the positioning shaft 491. Preferably, an anti-slip pad 495 is provided on the top of the upper pressure plate 492, and the bottom of the fastening nut 496 is pressed against the anti-slip pad 495. Furthermore, a limiting ring 46 matching the bottom of the impeller cylinder 1 is fixed at the top center of the support base plate 43.

[0020] It is worth mentioning that the bottom limiting ring 46 pre-positions the radial centering of the impeller cylinder 1, while the positioning shaft 491, inserted in the center, works in conjunction with the screw-on fastening nut 496 to force the upper pressure plate 492 to press downwards. The lower pressure plate 494 precisely fits into the limiting groove 493 at the axis of the main impeller 3, thus forming a three-dimensional locking mechanism of axial gravity pressing and radial concave-convex fitting. This provides an absolutely stable and deformation-resistant central assembly reference for the various moving blades 2 distributed in the outer circumferential array, eliminating the problem of misalignment of the main body during the welding process.

[0021] Based on the aforementioned center reference locking, this invention features a specific design for the reference alignment of the lower positioning plate 42. Specifically, a limiting ring groove 44 is formed on the bottom surface of the lower positioning plate 42, and a limiting ring body 45 is detachably connected to the inner side of the limiting ring groove 44. This limiting ring body 45 is fixedly connected to the supporting base plate 43 below. The insertion and engagement of the limiting ring body 45 and the limiting ring groove 44 ensures the coaxiality of the lower positioning plate 42 relative to the center positioning axis 491, thereby ensuring the precise positioning coordinates of the circumferential array arrangement at the root of the moving blades 2.

[0022] To achieve high-precision installation of the spatially twisted moving blade 2, several upper slots 47 arranged in a circular array are formed on the lower surface of the upper positioning plate 41, and several lower slots 48 arranged in a circular array are formed on the upper surface of the lower positioning plate 42; the upper slots 47 and lower slots 48 are staggered in spatial phase. In the assembled state, the upper and lower sides of each moving blade 2 are slidably connected to and limited by the corresponding upper slots 47 and lower slots 48, and the inner edge of the moving blade 2 is tightly fitted to the outer wall of the impeller cylinder 1.

[0023] Because existing processes rely on laser scribing to assist manual visual alignment, or use fixtures that only fix one side of the air inlet or outlet for constraint, the unconstrained end of the blades of the mixed-flow fan inevitably sags due to gravity or thermal strain due to the complex three-dimensional torsion and self-weight of the blades. This results in the blades' three-dimensional spatial angles exceeding tolerances, which in turn severely deteriorates the aerodynamic performance of the fan.

[0024] The upper and lower slots 48 interlock simultaneously clamp the leading edge inlet and trailing edge outlet of the moving blade 2, achieving true three-dimensional double-end constraint. The upper and lower sides of the moving blade 2 slide into the upper slot 47 and lower slot 48 respectively, and its three-dimensional spatial angle is forcibly limited, effectively resisting the slippage due to the blade's own weight and welding thermal deformation. This ensures that the actual flow pattern after molding is highly consistent with the theoretical design flow pattern, thereby significantly guaranteeing the aerodynamic performance of the fan, such as flow rate and total pressure.

[0025] In a double-end constraint positioning fixture, if the axial spacing and circumferential phase between the upper and lower constraint plates cannot be forcibly fixed, the correspondence between the upper slot 47 and the lower slot 48 will be disordered; and after welding, due to the complex structure of the impeller, the rigid fixing fixture is often extremely difficult to disassemble and demold.

[0026] Furthermore, in order to maintain the relative spatial coordinates of the upper and lower slots 48, the positioning mechanism 4 also includes a connecting component 5 disposed between the upper positioning plate 41 and the lower positioning plate 42, for fixing the interval size between the two. Specifically, the connecting component 5 includes several circumferentially arrayed limiting shafts 51 disposed on the outside of the impeller cylinder 1, and several threaded holes 52 opened on the lower positioning plate 42. The bottom of the limiting shaft 51 is screwed into the threaded hole 52 to achieve a rigid threaded connection; the top of the limiting shaft 51 passes through the upper positioning plate 41 and forms a sliding fit guide with it; finally, a fastening nut 53 is threadedly connected to the top of the limiting shaft 51 to lock the upper positioning plate 41.

[0027] By using the circumferentially distributed limiting shafts 51 in conjunction with the bottom thread and the top fastening nut 53, a stable support frame is formed between the lower positioning plate 42 and the upper positioning plate 41. This precisely locks the relative three-dimensional axial spacing and torsion angle between the upper slot 47 and the lower slot 48, ensuring the consistency of the installation posture of all moving blades 2. Simultaneously, the detachable design of the bottom threaded connection, top sliding guide, and nut locking allows the upper positioning plate 41 to be smoothly pulled upwards along the limiting shafts 51 after welding, simply by removing the second fastening nut 53. Subsequently, the limiting shafts 51 and the lower positioning plate 42 can be removed, achieving rapid and non-destructive demolding of the welded impeller, greatly improving production efficiency.

[0028] In actual use, the impeller blade positioning device first places the lower positioning plate 42 on top of the support base plate 43, so that the limiting ring groove 44 at the bottom of the lower positioning plate 42 is precisely engaged with the outer side of the limiting ring 45 fixed on the support base plate 43, thereby completing the initial anchoring of the lower positioning plate 42 in circumferential and radial coordinates. Next, the impeller cylinder 1 to be welded, together with the internal main impeller 3, is hoisted onto the support base plate 43, so that the bottom edge of the impeller cylinder 1 is tightly nested around the outer circumference of the limiting ring 46 in the center of the support base plate 43, completing the radial centering of the bottom of the impeller body. Subsequently, the bottom end of the positioning shaft 491 is passed through the center of the main wheel 3 and screwed into the threaded hole 497 in the center of the support base plate 43 for column anchoring; the lower pressure plate 494 is fitted over the positioning shaft 491, so that its bottom protruding structure is precisely fitted into the limiting circular groove 493 at the axis of the main wheel 3; the upper pressure plate 492 and the anti-slip pad 495 are then fitted onto the top of the positioning shaft 491, and the fastening nut 496 is tightened. With the downward stroke of the fastening nut 496, the upper pressure plate 492 transmits the clamping force evenly to the main wheel 3 through the lower pressure plate 494, thereby rigidly pressing the impeller cylinder 1 onto the support base plate 43 in the axial direction.

[0029] Subsequently, several moving blades 2 are inserted sequentially between the lower positioning plate 42 and the upper positioning plate 41 along the circumferential direction, so that the upper and lower sides of the moving blades 2 are respectively inserted into the upper slot 47 and the lower slot 48, and at the same time, the inner edge of each moving blade 2 is tightly fitted with the outer wall of the impeller cylinder 1, completing the root positioning. At this stage, the bottom ends of several limiting shafts 51 are screwed into the corresponding threaded holes 52 of the lower positioning plate 42, so that the limiting shafts 51 are arranged in a circumferential array and upright along the outer side of the impeller cylinder 1.

[0030] Next, the upper positioning plate 41 is moved horizontally to directly above the limiting shaft 51, so that the top of the limiting shaft 51 passes through the guide hole of the upper positioning plate 41. The upper positioning plate 41 is then smoothly pressed down vertically along the limiting shaft 51. During the downward pressing and closing process, the top of each moving blade 2 is inserted into the corresponding upper slot 47. After installation, the second fastening nut 53 is tightened on the top of each limiting shaft 51. The axial preload applied by the second fastening nut 53 forces the upper positioning plate 41 and the lower positioning plate 42 to maintain a fixed interval, so that the upper and lower ends of all moving blades 2 are rigidly physically limited by the upper slot 47 and the lower slot 48, completing the precise positioning. Finally, the welding operator or automatic welding equipment performs welding operations on the fitting gap between the moving blades 2 and the outer wall of the impeller cylinder 1.

[0031] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A positioning device for welded impeller blades of a mixed-flow fan, comprising a plurality of circumferentially arrayed moving blades (2) disposed on the outer side of the impeller cylinder (1), and a main impeller disk (3) fixed on the inner side of the impeller cylinder (1), characterized in that: The outer side of the impeller cylinder (1) is provided with a positioning mechanism (4) for limiting its installation position with several moving blades (2) during the welding process. The positioning mechanism (4) includes an upper positioning plate (41) and a lower positioning plate (42) arranged sequentially from top to bottom, and a support base plate (43) arranged at the bottom of the lower positioning plate (42) and in contact with the bottom of the impeller cylinder (1). The lower surface of the upper positioning plate (41) is provided with a plurality of upper slots (47) arranged in a circular array, and the upper surface of the lower positioning plate (42) is provided with a plurality of lower slots (48) arranged in a circular array. The support base plate (43) is provided with a locking assembly (49) for fixing the impeller cylinder (1).

2. The positioning device for welding impeller blades of a mixed-flow fan according to claim 1, characterized in that: The lower positioning plate (42) has a limiting ring groove (44), and a limiting ring body (45) fixed to the supporting base plate (43) is detachably connected to the inner side of the limiting ring groove (44).

3. The positioning device for welding impeller blades of a mixed-flow fan according to claim 1, characterized in that: The top center of the support base plate (43) is fixed with a limiting ring (46) that matches the bottom of the impeller cylinder (1).

4. The positioning device for welding impeller blades of a mixed-flow fan according to claim 1, characterized in that: The upper slot (47) and the lower slot (48) are arranged alternately. The upper and lower sides of the moving blade (2) are slidably connected to the upper slot (47) and the lower slot (48) respectively, and one side of the moving blade (2) is in contact with the outer wall of the impeller cylinder (1).

5. The positioning device for welding impeller blades of a mixed-flow fan according to claim 1, characterized in that: The locking assembly (49) includes a positioning shaft (491) disposed inside the impeller cylinder (1) and an upper pressure plate (492) sleeved on the top of the positioning shaft (491). A limiting groove (493) is provided at the center of the main wheel (3). A lower pressure plate (494) matching the limiting groove (493) is provided at the bottom of the upper pressure plate (492), and the lower pressure plate (494) is movably sleeved with the positioning shaft (491).

6. The positioning device for welding impeller blades of a mixed-flow fan according to claim 5, characterized in that: The top of the upper pressure plate (492) is provided with an anti-slip pad (495), the top of the positioning shaft (491) is threaded with a fastening nut (496) whose bottom contacts the anti-slip pad (495), and the center of the support base plate (43) is provided with a threaded hole (497) that is threaded to the bottom end of the positioning shaft (491).

7. The positioning device for welding impeller blades of a mixed-flow fan according to claim 1, characterized in that: The positioning mechanism (4) further includes a connecting component (5) disposed between the upper positioning plate (41) and the lower positioning plate (42), the connecting component (5) being used to fix the upper positioning plate (41) and the lower positioning plate (42) at fixed intervals.

8. The positioning device for welding impeller blades of a mixed-flow fan according to claim 7, characterized in that: The connecting assembly (5) includes several circumferentially arrayed limiting shafts (51) arranged on the outside of the impeller cylinder (1), and several threaded holes (52) opened on the lower positioning plate (42). The bottom of the limiting shaft (51) is threadedly connected to the threaded holes (52), and the top of the limiting shaft (51) passes through the upper positioning plate (41) and is slidably connected to it. The top of the limiting shaft (51) is threadedly connected to a fastening nut (53).

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