Fire pump capable of improving large-flow hump phenomenon

Abstract

The invention discloses a fire pump capable of improving a large-flow hump phenomenon. The fire pump comprises an impeller, a rotating shaft and a volute, and the impeller comprises a front cover plate, a rear cover plate, blades and a hub; the impeller is characterized in that the impeller further comprises a connecting disc, the radial inner side end of the rear cover plate is provided with an embedded ring and a connecting neck part which are sequentially connected, the left end face of the hub is provided with a first groove, the right end face of the connecting disc is provided with a second groove, and the embedded ring is installed in an installation cavity formed by the first groove and the second groove in a matched mode. The connecting neck part is mounted in a mounting channel formed by matching the radial outer end of the hub and the radial outer end of the connecting disc, an internal thread is arranged on the sleeve body at the radial inner side end of the connecting disc, and the connecting disc is in threaded connection with the rotating shaft through the internal thread. The pressure pulsation of the fire pump can be reduced / adjusted, the pressure loss / flow loss can be reduced, and the large-flow hump phenomenon can be improved or eliminated, so that the hydraulic performance and the multi-working-condition operation efficiency of the fire pump can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of fire pumps, and in particular to a fire pump capable of improving a large flow hump phenomenon. Background Art

[0002] The existing fire pump includes a centrifugal impeller, a rotating shaft, and a volute. The impeller is rotatably installed in the volute, and the impeller is installed on the rotating shaft. The rotating shaft is connected to the motor transmission. The impeller includes a front cover plate, a rear cover plate, blades, and a hub. A plurality of blades are distributed along the circumference and connected between the front cover plate and the rear cover plate. A hub is provided on the radial inner side of the rear cover plate, and the hub is installed on the rotating shaft. However, the existing fire pump still has problems such as pressure pulsation, large flow loss, and hump phenomenon, which affect the hydraulic performance and multi-condition operation efficiency of the fire pump. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a fire pump that improves the large flow hump phenomenon. Through the innovative design of the impeller structure, it can reduce / adjust the pressure pulsation of the fire pump, reduce the pressure loss / flow loss, and improve or eliminate the large flow hump phenomenon, thereby improving the hydraulic performance and multi-operating efficiency of the fire pump.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A fire pump for improving the large flow hump phenomenon comprises an impeller, a rotating shaft and a volute, wherein the impeller comprises a front cover plate, a rear cover plate, blades and a hub, wherein a plurality of blades are distributed circumferentially and connected between the front cover plate and the rear cover plate, a hub is arranged on the radial inner side of the rear cover plate, and the hub is mounted on the rotating shaft; the characteristic is that the impeller also comprises a connecting disk, an embedded ring and a connecting neck which are connected in sequence are arranged on the radial inner end of the rear cover plate, a first groove is provided on the left end face of the hub, a second groove is provided on the right end face of the connecting disk, the embedded ring is installed in an installation cavity formed by the cooperation of the first groove and the second groove, the connecting neck is installed in an installation channel formed by the cooperation of the radial outer end of the hub and the radial outer end of the connecting disk, an internal thread is arranged on the sleeve body at the radial inner end of the connecting disk, and the connecting disk is threadedly connected to the rotating shaft through the internal thread.

[0006] Furthermore, an elastic member is arranged in the first groove, one end of the elastic member is connected to the bottom of the first groove, and the other end is connected to the right end surface of the embedded ring.

[0007] Furthermore, the front cover plate, the rear cover plate and the blades are connected as a whole, the left end face of the sleeve body of the connecting disk is connected with a first nut, the first nut is threadedly connected to the rotating shaft, the right end face of the hub is connected with a second nut, and the second nut is threadedly connected to the rotating shaft.

[0008] Furthermore, the cross section of the embedded ring is rectangular, the first groove is an annular groove, the second groove is an annular groove, and the connecting neck is an annular neck.

[0009] Furthermore, the diameter of the central inlet hole of the front cover plate is larger than the outer diameter of the hub; during assembly, the front cover plate, the rear cover plate and the blades are first connected as a whole, and then the hub and the second nut are installed on the right end of the rotating shaft in sequence, and then the embedded ring of the whole is installed in the first groove, and then the connecting plate is pressed onto the rear cover plate from the left end so that the embedded ring is installed in the installation cavity formed by the first groove and the second groove, and the first gap between the connecting plate and the hub is adjusted by the axial tightening position of the internal thread, and the axial position of the whole is adjustable under the action of the preset elastic force of the elastic member, and the gap between the corresponding right end face of the front cover plate, the left end face of the rear cover plate and the corresponding side wall of the volute is adjustable, and locked by the first nut.

[0010] Furthermore, under different working conditions, the whole can be adjusted to different axial positions; under the first working condition, the whole can be adjusted to the first axial position, at this time there is a first gap between the connecting plate and the hub, the elastic member has a preset elastic force, and the whole can automatically adjust its axial position under the action of water pressure, and the range of automatic adjustment of its axial position depends on the preset elastic force of the elastic member; under the second working condition, the whole can be adjusted to the second axial position; under the third working condition, the whole can be adjusted to the third axial position.

[0011] Furthermore, a reflux flow hole is provided on the connecting disk, a first gap is provided between the right end surface of the connecting disk and the first left end surface of the hub, a first connecting groove is provided on the inner circumference of the embedded ring, a second connecting groove is provided on the outer circumference of the embedded ring, and a second gap is provided between the right end surface of the connecting neck and the second left end surface of the hub; the reflux path formed is: the back pressure cavity on the left side of the rear cover plate → reflux flow hole → first gap → first connecting groove → mounting cavity → second connecting groove → second gap → impeller inner cavity.

[0012] Further, the plurality of first connecting grooves are distributed along the circumferential direction, and the plurality of second connecting grooves are distributed along the circumferential direction.

[0013] Furthermore, the inner side surface of the front cover plate is provided with a first inclined surface and a first plane connected in sequence, the outer diameter of the first plane is equal to the outer diameter of the impeller, and the inner side surface of the rear cover plate is provided with a second inclined surface and a second plane connected in sequence, the outer diameter of the second plane is equal to the outer diameter of the impeller, and an angle a is formed between the first inclined surface and the second inclined surface, a=5-30°.

[0014] Further, the blade has a trailing edge end, the outer diameter of the trailing edge end is equal to the outer diameter of the first inclined surface and / or the second inclined surface, and the outer diameter of the trailing edge end is equal to the inner diameter of the first plane and / or the second plane.

[0015] The present invention discloses a fire pump for improving the large flow hump phenomenon. Through the innovative design of the impeller structure, the fire pump can reduce / adjust the pressure pulsation of the fire pump, reduce the pressure loss / flow loss, and can improve or eliminate the large flow hump phenomenon, thereby improving the hydraulic performance and multi-operating efficiency of the fire pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the structure of a fire pump for improving the large flow hump phenomenon of the present invention;

[0017] Figure 2 The schematic diagram of the fire pump structure for improving the large flow hump phenomenon of the present invention.

[0018] In the figure: centrifugal impeller 1, rotating shaft 2, front cover plate 3, rear cover plate 4, blades 5, hub 6, connecting plate 7, first nut 8, second nut 9, first inclined surface 31, first plane 32, embedded ring 41, connecting neck 42, first connecting groove 43, second connecting groove 44, second inclined surface 45, second plane 46, trailing edge end 51, first groove 61, elastic member / spring 62, second groove 71, internal thread 72, balance / reflux hole 73, first gap g1, second gap g2. DETAILED DESCRIPTION

[0019] In order to make the technical solution and advantages of the present invention clearer, the technical solution of the present invention will be further described in detail in detail with reference to the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present invention, which are only used to explain the present invention, not to limit the present invention. It should be noted that, for the convenience of description, only the parts / structures related to the present invention are shown in the accompanying drawings, and other related parts can refer to the general design. In the absence of conflict, the embodiments of the present invention and the technical features in the embodiments can be combined with each other to obtain new embodiments.

[0020] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. In addition, unless otherwise defined, the technical terms or scientific terms used in the description of the present invention should be the common meanings understood by ordinary technicians in the field to which the present invention belongs.

[0021] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0022] like Figure 1-2As shown, a fire pump for improving the hump phenomenon of large flow rate comprises a centrifugal impeller 1, a rotating shaft 2, and a volute. The impeller 1 is rotatably mounted in the volute. The impeller 1 is mounted on the rotating shaft 2. The rotating shaft 2 is connected to the motor transmission. The impeller 1 comprises a front cover plate 3, a rear cover plate 4, blades 5, and a hub 6. A plurality of blades 5 are distributed along the circumferential direction and connected between the front cover plate 3 and the rear cover plate 4. A hub 6 is arranged on the radial inner side of the rear cover plate 4. The hub 6 is mounted on the rotating shaft 2. The impeller 1 also comprises a connecting plate 7. The radial inner side of the rear cover plate 4 is provided with a hub 6. The hub 6 is mounted on the rotating shaft 2. The impeller 1 also comprises a connecting plate 7. The radial inner side of the rear cover plate 4 is provided with a hub 6. The hub 6 is mounted on the rotating shaft 2. The inner end is provided with an embedded ring 41 and a connecting neck 42 which are connected in sequence. The left end face of the hub 6 is provided with a first groove 61, and the right end face of the connecting disk 7 is provided with a second groove 71. The embedded ring 41 is installed in an installation cavity formed by the first groove 61 and the second groove 71. The connecting neck 42 is installed in an installation channel formed by the radial outer end of the hub 6 and the radial outer end of the connecting disk 7. An internal thread 72 is provided on the sleeve body at the radial inner end of the connecting disk 7, and the connecting disk 7 is threadedly connected to the rotating shaft 2 through the internal thread 72.

[0023] An elastic member / spring 62 is disposed in the first groove 61 , one end of the elastic member 62 is connected / abutted against the bottom of the first groove 61 , and the other end is connected / abutted against the right end surface of the embedded ring 41 .

[0024] The front cover plate 3, the rear cover plate 4 and the blade 5 are connected as a whole. The left end face of the sleeve body of the connecting disk 7 is connected with a first nut 8, and the first nut 8 is threadedly connected to the rotating shaft 2. The right end face of the hub 6 is connected with a second nut 9, and the second nut 9 is threadedly connected to the rotating shaft 2.

[0025] The cross section of the embedded ring 41 is rectangular, the first groove 61 is an annular groove, the second groove 71 is an annular groove, and the connecting neck 42 is an annular neck.

[0026] In one embodiment, the diameter of the central inlet hole of the front cover plate 3 is larger than the outer diameter of the hub 6; during assembly, the front cover plate 3, the rear cover plate 4 and the blade 5 are first connected as a whole, and then the hub 6 and the second nut 9 are installed on the right end of the rotating shaft 2 in sequence, and then the embedded ring 41 of the whole is installed in the first groove 61, and then the connecting plate 7 is pressed onto the rear cover plate 4 from the left end so that the embedded ring 41 is installed in the installation cavity formed by the first groove 61 and the second groove 71, and the first gap g1 between the connecting plate 7 and the hub 6 is adjusted by the axial tightening position of the internal thread 72, and the axial position of the whole can be adjusted or changed under the action of the preset elastic force of the elastic member 62, and the gap between the corresponding right end face of the front cover plate 3, the left end face of the rear cover plate 4 and the corresponding side wall of the volute can be adjusted or changed, and locked by the first nut 8.

[0027] The fire pump of the present invention improves the large flow hump phenomenon. Through the innovative design of the impeller 1 structure, the rear cover plate 4 is pressed from the left end by the connecting plate 7 so that the embedded ring 41 is installed in the installation cavity formed by the first groove 61 and the second groove 71, and the first gap g1 between the connecting plate 7 and the hub 6 is adjusted by the axial tightening position of the internal thread 72. Under the action of the preset elastic force of the elastic member / spring 62, the axial position of the whole can be adjusted or changed, and the gap between the right end face of the front cover plate 3, the left end face of the rear cover plate 4 and the corresponding side wall of the volute can be adjusted or changed. It can reduce / adjust the pressure pulsation of the fire pump, reduce the pressure loss / flow loss, improve or eliminate the large flow hump phenomenon, and thus improve the hydraulic performance and multi-operating efficiency of the fire pump.

[0028] Under different working conditions, the whole can be adjusted to different axial positions; for example, under the first working condition, the whole can be adjusted to the first axial position, at which time there is a first gap g1 between the connecting disk 7 and the hub 6, and the elastic member / spring 62 has a preset elastic force. The whole can automatically adjust its axial position under the action of water pressure, and the range of automatic adjustment of its axial position depends on the preset elastic force of the elastic member 62; under the second working condition, the whole can be adjusted to the second axial position; under the third working condition, the whole can be adjusted to the third axial position...

[0029] In one embodiment, a balancing / recirculation hole 73 is provided on the connecting disk 7, a first gap g1 is defined between the right end surface of the connecting disk 7 and the first left end surface of the hub 6, a first connecting groove 43 is defined on the inner circumference of the embedded ring 41, a second connecting groove 44 is defined on the outer circumference of the embedded ring 41, and a second gap g2 is defined between the right end surface of the connecting neck 42 and the second left end surface of the hub 6.

[0030] The reflux path formed is: the back pressure cavity on the left side of the rear cover plate 4 → the balance / reflux flow hole 73 → the first gap g1 → the first connecting groove 43 → the installation cavity → the second connecting groove 44 → the second gap g2 → the impeller inner cavity.

[0031] The plurality of first communicating grooves 43 are distributed along the circumferential direction, and the plurality of second communicating grooves 44 are distributed along the circumferential direction.

[0032] Through the design of the return path, the present invention can further reduce / regulate the pressure pulsation of the fire pump, reduce the pressure loss / flow loss, and can further improve or eliminate the large flow hump phenomenon, thereby further improving the hydraulic performance and multi-operating efficiency of the fire pump.

[0033] In one embodiment, the inner side surface of the front cover plate 3 is provided with a first inclined surface 31 and a first plane 32 connected in sequence, and the outer diameter of the first plane 32 is equal to the outer diameter of the impeller. The inner side surface of the rear cover plate 4 is provided with a second inclined surface 45 and a second plane 46 connected in sequence, and the outer diameter of the second plane 46 is equal to the outer diameter of the impeller. The first inclined surface 31 and the second inclined surface 45 have an angle a, a=10-20°.

[0034] The blade 5 has a trailing edge 51 , the outer diameter of which is equal to the outer diameter of the first inclined surface 31 and / or the second inclined surface 45 , and the outer diameter of which is equal to the inner diameter of the first plane 32 and / or the second plane 46 .

[0035] The fire pump is a centrifugal pump and the impeller is a centrifugal impeller.

[0036] The present invention can further reduce / regulate the pressure pulsation of the fire pump, reduce the pressure loss / flow loss, and further improve or eliminate the large flow hump phenomenon through the design of the impeller flow channel outlet end, thereby further improving the hydraulic performance and multi-operating efficiency of the fire pump.

[0037] The present invention discloses a fire pump for improving the large flow hump phenomenon. Through the innovative design of the impeller structure, the fire pump can reduce / adjust the pressure pulsation of the fire pump, reduce the pressure loss / flow loss, and can improve or eliminate the large flow hump phenomenon, thereby improving the hydraulic performance and multi-operating efficiency of the fire pump.

[0038] The above-mentioned implementation modes are for explanation of the present invention rather than limitation of the present invention. It can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A fire pump for improving the large flow hump phenomenon, comprising an impeller (1), a rotating shaft (2), and a volute, wherein the impeller comprises a front cover plate (3), a rear cover plate (4), blades (5), and a hub (6), wherein a plurality of blades are distributed along the circumferential direction and connected between the front cover plate and the rear cover plate, and a hub is arranged on the radial inner side of the rear cover plate, and the hub is mounted on the rotating shaft; the characteristics are as follows: The impeller also includes a connecting disk (7), the radial inner end of the rear cover plate is provided with an embedded ring (41) and a connecting neck (42) connected in sequence, the left end surface of the hub is provided with a first groove (61), the right end surface of the connecting disk is provided with a second groove (71), the embedded ring is installed in an installation cavity formed by the first groove and the second groove, the connecting neck is installed in an installation channel formed by the radial outer end of the hub and the radial outer end of the connecting disk, an internal thread (72) is provided on the sleeve body at the radial inner end of the connecting disk, and the connecting disk is threadedly connected to the rotating shaft through the internal thread.

2. A fire pump for improving large flow hump phenomenon as claimed in claim 1, characterized in that: An elastic member (62) is arranged in the first groove, one end of the elastic member is connected to the bottom of the first groove, and the other end is connected to the right end surface of the embedded ring.

3. A fire pump for improving large flow hump phenomenon as claimed in claim 2, characterized in that: The front cover plate, the rear cover plate and the blades are connected as a whole; the left end surface of the sleeve body of the connecting disk is connected with a first nut (8) which is threadedly connected to the rotating shaft; the right end surface of the hub is connected with a second nut (9) which is threadedly connected to the rotating shaft.

4. A fire pump for improving large flow hump phenomenon as claimed in claim 3, characterized in that: The cross section of the embedded ring (41) is rectangular, the first groove (61) is an annular groove, the second groove (71) is an annular groove, and the connecting neck (42) is an annular neck.

5. A fire pump for improving large flow hump phenomenon as claimed in claim 3, characterized in that: The diameter of the central inlet hole of the front cover plate is larger than the outer diameter of the hub; during assembly, the front cover plate, the rear cover plate and the blades are first connected as a whole, and then the hub and the second nut are installed on the right end of the rotating shaft in sequence, and then the embedded ring of the whole is installed in the first groove, and then the connecting plate is pressed onto the rear cover plate from the left end so that the embedded ring is installed in the installation cavity formed by the first groove and the second groove, and the first gap (g1) between the connecting plate and the hub is adjusted by the axial tightening position of the internal thread, and the axial position of the whole can be adjusted under the action of the preset elastic force of the elastic member, and the gap between the corresponding right end face of the front cover plate, the left end face of the rear cover plate and the corresponding side wall of the volute can be adjusted, and locked by the first nut.

6. A fire pump for improving large flow hump phenomenon as claimed in claim 3, characterized in that: Under different working conditions, the whole can be adjusted to different axial positions; under the first working condition, the whole can be adjusted to the first axial position, at which time there is a first gap (g1) between the connecting disk and the hub, and the elastic member (62) has a preset elastic force, and the whole can automatically adjust its axial position under the action of water pressure, and the range of automatic adjustment of its axial position depends on the preset elastic force of the elastic member; under the second working condition, the whole can be adjusted to the second axial position; under the third working condition, the whole can be adjusted to the third axial position.

7. A fire pump for improving large flow hump phenomenon as claimed in claim 3 or 6, characterized in that: A reflux hole (73) is provided on the connection disk, a first gap (g1) is provided between the right end surface of the connection disk and the first left end surface of the hub, a first connecting groove (43) is provided on the inner circumference of the embedded ring, a second connecting groove (44) is provided on the outer circumference of the embedded ring, and a second gap (g2) is provided between the right end surface of the connecting neck and the second left end surface of the hub; the reflux path formed is: the left back pressure cavity of the rear cover plate (4) → the reflux hole (73) → the first gap (g1) → the first connecting groove (43) → the installation cavity → the second connecting groove (44) → the second gap (g2) → the inner cavity of the impeller.

8. A fire pump for improving large flow hump phenomenon as claimed in claim 7, characterized in that: The plurality of first communicating grooves are distributed along the circumferential direction, and the plurality of second communicating grooves are distributed along the circumferential direction.

9. A fire pump for improving large flow hump phenomenon as claimed in claim 3 or 6, characterized in that: The inner side surface of the front cover plate is provided with a first inclined surface (31) and a first plane (32) connected in sequence, the outer diameter of the first plane is equal to the outer diameter of the impeller, and the inner side surface of the rear cover plate is provided with a second inclined surface (45) and a second plane (46) connected in sequence, the outer diameter of the second plane is equal to the outer diameter of the impeller, and an angle a is formed between the first inclined surface and the second inclined surface, a=5-30°.

10. A fire pump for improving large flow hump phenomenon as claimed in claim 9, characterized in that: The blade has a trailing edge end (51), the outer diameter of which is equal to the outer diameter of the first inclined surface and / or the second inclined surface, and the outer diameter of which is equal to the inner diameter of the first plane and / or the second plane.

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