Impeller backlash fine adjustment mechanism

Abstract

The invention relates to an impeller backlash fine adjustment mechanism. The gear box comprises a gear box body, the first transmission assembly is arranged on the gear box body and comprises a first transmission shaft as well as a first thrust disc I, an adjustable bearing, a first thrust disc II and a first gear which are sequentially arranged on the first transmission shaft; the adjusting assembly comprises a mounting seat mounted on the gear box body, a connecting piece and an adjusting pad, and the adjusting part and the mounting seat are connected through the connecting piece so that the adjusting pad can abut against the position between the first face and the second face; the second transmission assembly is arranged on the gear box body and comprises a second transmission shaft as well as a second thrust disc I, a second gear and a second thrust disc II which are sequentially arranged on the second transmission shaft; the impeller assembly comprises a volute and an impeller arranged in the volute and connected with the second transmission shaft, an impeller backlash is formed between the volute and the impeller, and the size of the impeller backlash can be adjusted by adjusting the thickness of an adjusting pad. The impeller backlash can be adjusted without opening a gearbox cover.

Description

Technical Field

[0001] The invention relates to the technical field of centrifugal fans, and in particular to an impeller side clearance fine-tuning mechanism. Background Art

[0002] In the production and maintenance process of existing single-stage high-speed centrifugal fans, the gap between the semi-open impeller and the volute (usually called the impeller side clearance) needs to be precisely adjusted. If the side clearance is too large, the impeller efficiency will decrease; if the side clearance is too small, it may cause scratches, damage the impeller, and even cause the entire high-speed rotor to be scrapped.

[0003] In existing small-sized fans with thrust disc structure and horizontal parting, the adjustment of impeller side clearance usually depends on changing the thickness of the gaskets in the two bearing slots of the low-speed shaft. This adjustment method requires the removal of the gearbox cover, which is complicated and labor-intensive, and greatly increases the difficulty and inconvenience of maintenance, especially in a field environment with limited space. Summary of the invention

[0004] To this end, the present invention provides an impeller side clearance fine-tuning mechanism, which can adjust the impeller side clearance without opening the gear box cover, saving time and labor costs, and can be easily operated even in limited space.

[0005] In order to solve the above technical problems, the present invention provides an impeller side clearance fine-tuning mechanism, comprising: Gear box; A first transmission assembly is arranged on the gear housing, comprising a first transmission shaft and a first thrust plate I, an adjustable bearing, a first thrust plate II and a first gear sequentially arranged on the first transmission shaft; wherein the first adjustable bearing is matched with the axial clearance between the first thrust plate I and the first thrust plate II, the adjustable bearing is provided with an adjustment portion, and the adjustment portion has a first surface; An adjustment assembly, comprising a mounting seat, a connecting member and an adjustment pad mounted on the gear housing, wherein the mounting seat has a second surface facing the first surface, and the connecting member connects the adjustment portion and the mounting seat and allows the adjustment pad to be pressed tightly between the first surface and the second surface; A second transmission assembly is arranged on the gear housing, comprising a second transmission shaft and a second thrust plate I, a second gear and a second thrust plate II which are arranged on the second transmission shaft in sequence; wherein the radial outer end of the first gear is matched with the axial clearance between the second thrust plate I and the second thrust plate II, and the second gear is meshed with the first gear; The impeller assembly comprises a volute and an impeller arranged in the volute and connected to the second transmission shaft. The volute forms an impeller side gap between the impeller and the impeller. The size of the impeller side gap can be adjusted by adjusting the thickness of the adjustment pad.

[0006] In one embodiment of the present invention, the adjusting portion extends radially outward along the adjustable bearing and forms an annular structure.

[0007] In one embodiment of the present invention, the mounting seat includes a mounting portion connected to the gear housing and a connecting portion extending from the mounting portion, and an adjustment groove for the adjustment portion to extend into is formed between the mounting portion, the connecting portion and the gear housing.

[0008] In one embodiment of the present invention, the mounting portion abuts against the gear housing and the two are connected via fixing screws.

[0009] In one embodiment of the present invention, the connecting member comprises a fastening screw, and the fastening screw passes through the connecting portion and the adjusting pad in sequence and is threadedly connected to the connecting portion.

[0010] In one embodiment of the present invention, the diameter of the first gear is greater than the diameter of the second gear, and the rotation speed of the first transmission shaft is lower than the rotation speed of the second transmission shaft.

[0011] In one embodiment of the present invention, a first fixed bearing is installed in the gear box body, and one end of the first transmission shaft close to the volute is installed in the shaft hole of the first fixed bearing.

[0012] In one embodiment of the present invention, a second fixed bearing and a third fixed bearing are installed in the gear box body, and two ends of the second transmission shaft are respectively installed in the shaft holes of the second fixed bearing and the third fixed bearing.

[0013] In one embodiment of the present invention, the first thrust plate I and the first thrust plate II respectively form a bidirectional thrust bearing with the axial ends of the first adjustable bearing, and the second thrust plate I and the second thrust plate II respectively form a bidirectional thrust surface with the axial ends of the radial outer side of the first gear.

[0014] In one embodiment of the present invention, the impeller side clearance is controlled at 0.5-0.7 mm.

[0015] The above technical solution of the present invention has the following advantages compared with the prior art: The impeller side clearance fine-tuning mechanism described in the present invention realizes external fine-tuning of the impeller side clearance through the cooperation of an adjustable bearing, a connecting piece and an adjusting pad. The adjustment can be completed only by adjusting the thickness of the adjusting pad. This solves the problem that the adjustment of the existing impeller side clearance usually requires disassembly of the gear box cover, which is cumbersome to operate and difficult to implement in a small space. It greatly reduces maintenance time and labor costs and improves maintenance efficiency.

[0016] Since the adjustment assembly of the present invention is arranged outside the gear box, no additional disassembly space is required, and convenient impeller side clearance adjustment can be achieved even under space-constrained working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0018] Figure 1 It is a schematic diagram of the overall structure of the impeller side clearance fine-tuning mechanism of the present invention.

[0019] Figure 2 yes Figure 1 A partial enlarged schematic diagram of .

[0020] Description of the Figures in the Specification: 1. Gear box; 2. First transmission shaft; 21. First thrust plate I; 22. First thrust plate II; 23. First gear; 3. Adjustable bearing; 31. Adjustment part; 32. First surface; 4. Connecting piece; 5. Adjusting pad; 6. Fixing screw; 7. Mounting seat; 71. Second surface; 72. Mounting portion; 73. Connecting portion; 74. Adjusting groove; 8. First fixed bearing; 9. Second transmission shaft; 10. Second fixed bearing; 11. Third fixed bearing; 12. Volute; 91. Second gear; 92. Second thrust plate I; 93. Second thrust plate II; 94. Impeller; 95. Fastening component. DETAILED DESCRIPTION

[0021] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0022] In the present invention, if directions (up, down, left, right, front and back) are described, it is only for the convenience of describing the technical solution of the present invention, and does not indicate or imply that the technical features referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, it cannot be understood as a limitation of the present invention.

[0023] In the present invention, "several" means one or more, "multiple" means more than two, "greater than", "less than", "exceed" and the like are understood to exclude the number itself; "above", "below", "within" and the like are understood to include the number itself. In the description of the present invention, if there is a description of "first" or "second", it is only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0024] In the present invention, unless otherwise clearly defined, the words "set", "install", "connect" and the like should be understood in a broad sense, for example, they can be directly connected or indirectly connected through an intermediate medium; they can be fixedly connected or detachably connected or integrally formed; they can be mechanically connected or electrically connected or able to communicate with each other; they can be the internal connection of two elements or the interaction relationship between two elements. Those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0025] Reference Figure 1 , Figure 2 As shown, an impeller side clearance fine-tuning mechanism of the present invention comprises: Gear box 1; The first transmission assembly is arranged on the gear box body 1, and includes a first transmission shaft 2 and a first thrust plate Ⅰ21, an adjustable bearing 3, a first thrust plate Ⅱ22 and a first gear 23 which are arranged on the first transmission shaft 2 in sequence; wherein the first adjustable bearing 3 is matched with the axial clearance between the first thrust plate Ⅰ21 and the first thrust plate Ⅱ22, the adjustable bearing 3 is provided with an adjustment portion 31, and the adjustment portion 31 has a first surface 32; the clearance (oil film thickness) between the first thrust plate Ⅰ21 and the adjustable bearing 3 is 0.01-0.05mm, and the total clearance is 0.15-0.25mm; since the first thrust plate Ⅰ21 basically bears all the axial force, the clearance at the first thrust plate Ⅰ21 is relatively small; An adjustment assembly, comprising a mounting seat 7, a connecting member 4 and an adjustment pad 5 mounted on the gear housing 1, wherein the mounting seat 7 has a second surface 71 facing the first surface 32, and the connecting member 4 connects the adjustment portion 31 and the mounting seat 7 and allows the adjustment pad 5 to be pressed tightly between the first surface 32 and the second surface 71; The second transmission assembly is arranged on the gear box body 1, including a second transmission shaft 9 and a second thrust plate I 92, a second gear 91 and a second thrust plate II 93 which are arranged on the second transmission shaft 9 in sequence; wherein the radial outer end of the first gear 23 is matched with the axial clearance between the second thrust plate I 92 and the second thrust plate II 93, and the second gear 91 is meshed with the first gear 23; the clearance (oil film thickness) between the second thrust plate I 92 and the first gear 23 is 0.01-0.05mm, and the total clearance is 0.15-0.25mm; since the second thrust plate I 92 basically bears all the axial force, the clearance at the second thrust plate I 92 is relatively small; The impeller assembly includes a volute 12 and an impeller 94 disposed in the volute 12 and connected to the second transmission shaft 9. The impeller 94 is fixedly connected to the second transmission shaft 9 through a fastening component 95. The volute 12 forms an impeller side gap between the impeller 94 and the impeller 94. By adjusting the thickness of the adjustment pad 5 ( Figure 2 m), it is possible to adjust the impeller side clearance ( Figure 1 The size of X in the image.

[0026] The adjustment of the existing impeller side clearance usually requires the removal of the gear box cover, which is cumbersome and difficult to implement in a small space. The present invention realizes external fine adjustment of the impeller side clearance through the combination of the adjustable bearing 3, the connecting member 4 and the adjustment pad 5. The adjustment can be completed by simply adjusting the thickness of the adjustment pad 5, which greatly reduces maintenance time and labor costs and improves maintenance efficiency.

[0027] Reference Figure 2 As shown, in one embodiment, the adjusting portion 31 extends radially outward along the adjustable bearing 3 and forms an annular structure.

[0028] Specifically, the mounting seat 7 includes a mounting portion 72 connected to the gear housing 1 and a connecting portion 73 extending from the mounting portion 72 , and an adjusting slot 74 for the adjusting portion 31 to extend into is formed between the mounting portion 72 , the connecting portion 73 and the gear housing 1 .

[0029] Specifically, the mounting portion 72 abuts against the gear housing 1 and the two are connected via a fixing screw 6 .

[0030] The connecting member 4 includes a fastening screw, which passes through the connecting portion 73 and the adjusting pad 5 in sequence and is threadedly connected to the connecting portion 73 .

[0031] In addition, the mounting seat 7 is composed of a mounting portion 72 and a connecting portion 73. The mounting portion 72 is connected to the gear box body 1 by a fixing screw 6 to ensure the stability of the overall structure. At the same time, an adjustment slot 74 is reserved for the adjustment portion 31 to extend into, thereby achieving flexible adjustment.

[0032] In one embodiment, a diameter of the first gear 23 is greater than a diameter of the second gear 91 , and a rotation speed of the first transmission shaft 2 is lower than a rotation speed of the second transmission shaft 9 .

[0033] Specifically, a first fixed bearing 8 is installed in the gear box 1 (fixed through a slot), and one end of the first transmission shaft 2 close to the volute 12 is installed in the shaft hole of the first fixed bearing 8 .

[0034] Specifically, a second fixed bearing 10 and a third fixed bearing 11 are installed in the gear box body 1 , and two ends of the second transmission shaft 9 are installed in the shaft holes of the second fixed bearing 10 and the third fixed bearing 11 , respectively.

[0035] Specifically, the first thrust plate I21 and the first thrust plate II22 are integrally structured with the first transmission shaft 2, and respectively form bidirectional thrust bearings with the axial ends of the first adjustable bearing 3, thereby axially positioning the first transmission shaft 2 and reducing axial movement during operation; the second thrust plate I92 and the second thrust plate II93 respectively form bidirectional thrust surfaces with the axial ends of the radial outer side of the first gear 23.

[0036] In one embodiment, the impeller side clearance is controlled at 0.5-0.7 mm to improve the working efficiency of the fan.

[0037] The working principle of this embodiment is as follows: the thickness of the adjustment pad 5 is increased, and the adjustable bearing 3 moves to the right. Since the force direction (to the right) and size of the first transmission shaft 2 are not changed, the first thrust plate I21 is subjected to the main axial force during operation, and the gap (oil film thickness) between the first thrust plate I21 and the adjustable bearing 3 remains unchanged. The axial force forces the first transmission shaft 2 and the first gear 23 to move to the right. Similarly, since the force direction (to the right) and size of the second transmission shaft 9 remain unchanged, the second thrust plate I92 on the second transmission shaft 9 is subjected to the main axial force, and the gap (oil film thickness) between the second thrust plate I92 and the first gear 23 remains unchanged. The axial force forces the second transmission shaft 9 and the impeller 94 to move to the right, thereby synchronously reducing the impeller side clearance; similarly, reducing the thickness of the adjustment pad 5 increases the impeller side clearance synchronously. The above adjustment operation does not require opening the gear box cover. It only needs to unscrew the fixing screw 6 from the side, remove the mounting seat 7, adjust the thickness of the adjustment pad 5, and then reinstall the mounting seat 7. In summary, by adjusting the thickness of the gasket 5 to increase or decrease △ on the original m, the impeller side clearance can be increased or decreased by △ on the original x, and finally the impeller side clearance can be controlled within 0.5~0.7mm, that is, m±△=x∓△=0.5~0.7mm. By reasonably controlling the impeller side clearance, the efficient and safe operation of the fan is ensured.

[0038] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. An impeller side clearance fine-tuning mechanism, characterized in that: include: Gear box (1); A first transmission assembly is arranged on the gear housing (1), comprising a first transmission shaft (2) and a first thrust plate I (21), an adjustable bearing (3), a first thrust plate II (22) and a first gear (23) which are arranged on the first transmission shaft (2) in sequence; wherein the first adjustable bearing (3) is matched with the first thrust plate I (21) and the first thrust plate II (22) by an axial clearance, the adjustable bearing (3) is provided with an adjustment portion (31), and the adjustment portion (31) has a first surface (32); An adjustment assembly, comprising a mounting seat (7), a connecting member (4) and an adjustment pad (5) mounted on the gear housing (1), the mounting seat (7) having a second surface (71) facing the first surface (32), the screw (4) connecting the adjustment portion (31) and the mounting seat (7) and causing the adjustment pad (5) to be pressed tightly between the first surface (32) and the second surface (71); a second transmission assembly, arranged on the gear housing (1), comprising a second transmission shaft (9) and a second thrust plate I (92), a second gear (91) and a second thrust plate II (93) arranged in sequence on the second transmission shaft (9); wherein the radial outer end of the first gear (23) is matched with the axial clearance between the second thrust plate I (92) and the second thrust plate II (93), and the second gear (91) is meshed with the first gear (23); An impeller assembly comprises a volute (12) and an impeller (94) disposed in the volute (12) and connected to the second transmission shaft (9), wherein an impeller side clearance is formed between the volute (12) and the impeller (94), and the size of the impeller side clearance can be adjusted by adjusting the thickness of the adjustment pad (5).

2. The impeller side clearance fine-tuning mechanism according to claim 1, characterized in that: The adjustment portion (31) extends radially outward along the adjustable bearing (3) and forms an annular structure.

3. An impeller side clearance fine-tuning mechanism according to claim 1 or 2, characterized in that: The mounting seat (7) comprises a mounting portion (72) connected to the gear housing (1) and a connecting portion (73) extending from the mounting portion (72), and an adjustment groove (74) for the adjustment portion (31) to extend into is formed between the mounting portion (72), the connecting portion (73) and the gear housing (1).

4. The impeller side clearance fine-tuning mechanism according to claim 3, characterized in that: The mounting portion (72) abuts against the gear housing (1) and the two are connected via a fixing screw (6).

5. The impeller side clearance fine-tuning mechanism according to claim 3, characterized in that: The connecting member (4) comprises a fastening screw, which passes through the connecting portion (73) and the adjusting pad (5) in sequence and is then threadedly connected to the connecting portion (73).

6. The impeller side clearance fine-tuning mechanism according to claim 1, characterized in that: The diameter of the first gear (23) is greater than the diameter of the second gear (91), and the rotation speed of the first transmission shaft (2) is lower than the rotation speed of the second transmission shaft (9).

7. The impeller side clearance fine-tuning mechanism according to claim 1, characterized in that: A first fixed bearing (8) is installed in the gear housing (1), and one end of the first transmission shaft (2) close to the volute (12) is installed in the shaft hole of the first fixed bearing (8).

8. The impeller side clearance fine-tuning mechanism according to claim 1, characterized in that: A second fixed bearing (10) and a third fixed bearing (11) are installed in the gear housing (1), and two ends of the second transmission shaft (9) are respectively installed in the shaft holes of the second fixed bearing (10) and the third fixed bearing (11).

9. The impeller side clearance fine-tuning mechanism according to claim 1, characterized in that: The first thrust plate I (21) and the first thrust plate II (22) respectively form bidirectional thrust bearings with the two axial ends of the first adjustable bearing (3), and the second thrust plate I (92) and the second thrust plate II (93) respectively form bidirectional thrust surfaces with the two axial ends of the radial outer side of the first gear (23).

10. The impeller side clearance fine-tuning mechanism according to claim 1, characterized in that: The impeller side clearance is controlled at 0.5-0.7 mm.

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