Variable frequency pump

Abstract

The invention provides a variable frequency pump, and belongs to the technical field of pumps. The technical problem that a sealing structure of an existing variable frequency pump is prone to being damaged due to frequent starting and stopping is solved. The variable frequency pump comprises a motor shell, a stator, a rotor and a rotating shaft are arranged in the motor shell, the lower portion of the rotating shaft is fixedly connected with an impeller, the upper portion of the motor shell is fixedly connected with an upper cap, a fixing seat is fixedly connected between the upper cap and the motor shell, a variable frequency component is fixedly connected between the fixing seat and the upper cap, and the lower portion of the motor shell is fixedly connected with an oil cylinder cover. An oil storage part is integrally formed on the lower portion of the motor shell, an oil storage cavity is formed between the oil storage part and the oil cylinder cover, and a mechanical sealing assembly is arranged in the oil storage cavity. According to the variable frequency pump, the variable frequency pump can better adapt to large changes of the rotating speed in the starting and stopping stages, vibration is reduced, and operation stability is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of pumps, and in particular relates to a variable frequency pump. Background Art

[0002] A variable frequency pump refers to a pump driven by a variable frequency motor that can adjust the speed and flow rate. In the prior art, there is a variable frequency electric pump with application number 2019108133983, in which the first end of the motor is connected to the pump body, the motor shaft is connected to the impeller, the impeller is in the pump body, and there is a sealing structure between the motor shaft and the pump body. However, during the start and stop phase of the variable frequency pump, the speed of the variable frequency pump will change greatly, which is easy to cause vibration of the pump. Frequent start and stop can easily damage its sealing structure and affect the operation of the variable frequency pump. Summary of the invention

[0003] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a variable frequency pump. The technical problem to be solved by the present invention is how to make the variable frequency pump run more smoothly during the start and stop stages.

[0004] The object of the present invention can be achieved through the following technical solutions: a variable frequency pump, including a motor housing, a stator and a rotor are arranged in the motor housing, a rotating shaft is fixedly connected to the middle of the rotor, an impeller is fixedly connected to the lower part of the rotating shaft, an upper cap is fixedly connected to the upper part of the motor housing, a fixing seat is fixedly connected between the upper cap and the motor housing, a variable frequency component is fixedly connected between the fixing seat and the upper cap, a cylinder cover is fixedly connected to the lower part of the motor housing, an oil storage part is integrally formed at the lower part of the motor housing, and an oil storage cavity is arranged between the oil storage part and the cylinder cover A mechanical seal assembly is arranged in the oil storage cavity, the lower part of the oil cylinder cover is fixedly connected to the pump casing, a pump cavity is formed between the lower end of the oil cylinder cover and the pump casing, the impeller is located in the pump cavity, a bearing seat 1 protrudes downward from the fixed seat, a bearing 1 is arranged in the bearing seat 1, a corrugated washer is arranged between the upper end of the bearing 1 and the bearing seat 1, a bearing seat 2 protrudes upward from the upper part of the oil storage part, a bearing 2 is arranged in the bearing seat 2, the upper part of the rotating shaft is fixed to the bearing 1, the middle part is fixed to the bearing 2, and the lower part is fixed to the impeller after passing through the mechanical seal assembly.

[0005] The frequency conversion component in this solution is fixed between the fixing seat and the upper cap, realizing the integrated design of the frequency conversion control and the motor, which is also beneficial to heat dissipation, simplifies the structure, and improves the compactness and installation convenience of the whole machine; a wave washer is provided between the upper end of the bearing 1 and the bearing seat 1, and the wave washer and the mechanical seal assembly are respectively arranged on the upper and middle parts of the rotating shaft, so that the frequency conversion pump can better adapt to large changes in speed during the starting and stopping stages, reduce vibration, and improve the running stability.

[0006] Furthermore, a control seat is fixedly connected to the middle of the inner wall of the upper cap, and the control seat includes an integrally formed circular fixing plate and a downwardly protruding annular heat dissipation wall, and the annular heat dissipation wall is tightly fitted with the inner wall of the upper cap, and the frequency conversion component is fixedly connected to the circular fixing plate. The annular heat dissipation wall is tightly fitted with the inner wall of the upper cap, which increases the heat dissipation area, can effectively conduct the heat generated by the frequency conversion component to the upper cap, and dissipate it to the external environment through the upper cap, so as to prevent the frequency conversion component from overheating.

[0007] Furthermore, the oil storage portion and the oil storage cavity are both conical, and a sealing seat 1 is provided on the upper portion of the oil storage portion facing away from the bearing seat 2, and the upper end of the mechanical seal assembly is sealed against the sealing seat 1, and a sealing seat 2 is provided on the upper portion of the cylinder cover, and the lower end of the mechanical seal assembly is sealed against the sealing seat 2.

[0008] Furthermore, the mechanical seal assembly includes two dynamic seals sealed and fixed to the rotating shaft and static seals sealed and fixed to the first sealing seat and the second sealing seat respectively, and an elastic member is arranged between the two dynamic seals.

[0009] Furthermore, the elastic member is a double helical spring, the dynamic seal protrudes with a spring seat, the double helical spring fixed sleeve is arranged on the spring seat, and the double helical spring is arranged parallel to the axial direction of the rotating shaft. The inner and outer layers of the double helical spring are parallel to the rotating shaft. The double helical spring enables the dynamic seal and the static seal to better maintain stability, increases the sealing effect of the dynamic seal and the static seal, and improves the service life of the mechanical seal assembly.

[0010] Furthermore, an energy storage component is fixedly connected between the oil storage part and the oil cylinder cover, and the energy storage component is elastic, and an energy storage cavity is formed between the energy storage component and the oil cylinder cover. The energy storage component and the energy storage cavity can store and release pressure energy. When the pressure in the oil storage cavity decreases, the stored energy is released to supplement the pressure, so as to keep the pressure between the sealing surfaces stable, avoid sealing failure due to pressure fluctuations, and thus extend the service life of the mechanical seal assembly. Especially during the start-up and stop stages of the variable frequency pump, the speed changes greatly, and the energy storage structure can effectively buffer the impact of pressure fluctuations on the mechanical seal assembly.

[0011] Furthermore, the upper end of the oil cylinder cover protrudes upward with coaxial circular ring blocks 1 and 2, and the energy storage component includes a flat ring portion and a first sealing fixing portion and a second sealing fixing portion protruding downward along the inner and outer sides of the flat ring portion, and the end of the first sealing fixing portion includes an integrally formed fixed sealing ring, the first sealing fixing portion is sleeved on the outer side of circular ring block 1 and fixed by the oil storage portion and the oil cylinder cover, and the second sealing fixing portion is fixed by the oil cylinder cover and the fixing member. The first sealing fixing portion is sleeved on the outer side of circular ring block 1 and fixed by the oil storage portion and the oil cylinder cover, and combined with the integrally formed fixed sealing ring, it can effectively prevent oil leakage and improve the sealing effect; the second sealing fixing portion is fixed by the oil cylinder cover and the fixing member, which enhances the connection strength between the energy storage component and the oil cylinder cover and ensures the stability and durability of the overall structure.

[0012] Compared with the prior art, the technical effects of the present invention are as follows: 1. The corrugated gasket and the mechanical seal assembly are respectively arranged at the upper and middle parts of the rotating shaft, so that the variable frequency pump can better adapt to large changes in rotation speed during the start-up and stop stages, thereby improving the running stability. 2. The double helical spring enables the dynamic seal and the static seal to better maintain stability, increases the sealing effect of the dynamic seal and the static seal, and improves the service life of the mechanical seal assembly. 3. The energy storage component and the energy storage chamber can store and release pressure energy. When the pressure in the oil storage chamber decreases, the stored energy is released to supplement the pressure, thereby maintaining the pressure of the sealing surface on the mechanical seal assembly stable, avoiding seal failure due to pressure fluctuations, and thus extending the service life of the mechanical seal assembly. Especially during the start-up and stop stages of the variable frequency pump, the rotation speed changes greatly, and the energy storage structure can effectively buffer the impact of pressure fluctuations on the mechanical seal assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a cross-sectional view of the present invention.

[0014] Figure 2 It is an enlarged view of point A of the present invention.

[0015] Figure 3 It is an enlarged view of B of the present invention.

[0016] Figure 4 It is a cross-sectional view of the energy storage component of the present invention.

[0017] Figure 5 It is a stereogram of the present invention.

[0018] Figure number marking: 1, motor housing; 101, oil storage part; 102, bearing seat 2; 103, sealing seat 1; 2, stator; 3, rotor; 4, rotating shaft; 5, impeller; 6, upper cap; 7, fixed seat; 701, bearing seat 1; 8, frequency conversion component; 9, cylinder cover; 901, sealing seat 2; 902, circular ring block 1; 903, circular ring block 2; 10, oil storage chamber; 11, pump housing; 1101, water inlet; 1102, water outlet Mouth; 12, pump chamber; 13, bearing one; 14, corrugated washer; 15, bearing two; 16, control seat; 1601, circular fixing plate; 1602, annular heat dissipation wall; 17, dynamic seal; 1701, spring seat; 18, static seal; 19, water filter; 20, elastic member; 21, energy storage member; 2101, first sealing fixing part; 2102, second sealing fixing part; 2103, sealing ring; 22, energy storage chamber. DETAILED DESCRIPTION

[0019] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0020] It should be noted that the descriptions of the present invention regarding directions such as “up”, “down”, “left”, “right”, “top” and “bottom” are all defined based on the relationships between the orientations or positions shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device must be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention.

[0021] according to Figures 1 to 5As shown, a variable frequency pump includes a motor housing 1 and a pump housing 11, wherein a stator 2 and a rotor 3 are arranged in the motor housing 1, and a rotating shaft 4 is fixedly connected in the middle of the rotor 3. The pump housing 11 has a water inlet 1101 and a water outlet 1102, and an impeller 5 is arranged in the pump housing 11. A water filter 19 is fixedly connected to the lower end of the pump housing 11, and the water filter 19 surrounds the water inlet 1101. The impeller 5 is fixedly connected to the lower part of the rotating shaft 4. The upper part of the motor housing 1 is fixedly connected to the upper cap 6, and a fixing seat 7 is fixedly connected between the upper cap 6 and the motor housing 1, and a frequency conversion component 8 is fixedly connected between the fixing seat 7 and the upper cap 6, and the frequency conversion component 8 includes a rectifier unit, a capacitor, an inverter and a controller. The frequency conversion component 8 is fixed between the fixing seat 7 and the upper cap 6, which realizes the integrated design of the frequency conversion control and the motor, is also conducive to heat dissipation, simplifies the structure, and improves the compactness and installation convenience of the whole machine. In order to make the frequency conversion component 8 dissipate heat better, the control seat 16 is fixedly connected to the middle of the inner wall of the upper cap 6. There is a large gap between the control seat 16 and the upper end of the upper cap 6 and the upper end of the fixed seat 7 to form an independent frequency conversion space. The control seat 16 includes an integrally formed circular fixed plate 1601 and a downwardly protruding annular heat dissipation wall 1602. The annular heat dissipation wall 1602 is tightly fitted with the inner wall of the upper cap 6, and the frequency conversion component 8 is fixedly connected to the circular fixed plate 1601. The annular heat dissipation wall 1602 is tightly fitted with the inner wall of the upper cap 6, which increases the heat dissipation area, can effectively conduct the heat generated by the frequency conversion component 8 to the upper cap 6, and dissipate it to the external environment through the upper cap 6 to prevent the frequency conversion component 8 from overheating.

[0022] The lower part of the motor housing 1 is fixedly connected to the oil cylinder cover 9. The lower part of the motor housing 1 is integrally formed with an oil storage part 101. The oil storage part 101 is located inside the motor housing 1. An oil storage chamber 10 is formed between the oil storage part 101 and the oil cylinder cover 9. A mechanical seal assembly is arranged in the oil storage chamber 10. The mechanical seal assembly is sleeved on the rotating shaft 4. The lower part of the oil cylinder cover 9 is fixedly connected to the pump housing 11. A pump chamber 12 is formed between the lower end of the oil cylinder cover 9 and the pump housing 11. The impeller 5 is located in the pump chamber 12. The fixed seat 7 protrudes downward with a bearing seat 1 701. A bearing 13 is arranged in the bearing seat 1 701. A wave washer 14 is arranged between the upper end of the bearing 13 and the bearing seat 1 701. The upper part of the oil storage part 101 protrudes upward with a bearing seat 2 102. A bearing 2 15 is arranged in the bearing seat 2 102. The upper part of the rotating shaft 4 is fixed to the bearing 13, the middle part is fixed to the bearing 2 15, and the lower part is fixed to the impeller 5 after passing through the mechanical seal assembly. The corrugated gasket 14 and the mechanical seal assembly are respectively arranged at the upper and middle parts of the rotating shaft 4, so that the variable frequency pump can better adapt to the large change of speed during the start and stop stages, reduce vibration, and improve the running stability. The oil storage part 101 and the oil storage cavity 10 are both conical, and the upper part of the oil storage part 101 is provided with a sealing seat 103 facing away from the bearing seat 2 102, and the upper end of the mechanical seal assembly is sealed against the sealing seat 103, and the upper part of the oil cylinder cover 9 is provided with a sealing seat 2 901, and the lower end of the oil cylinder cover 9 is provided with a sealing groove, and the sealing groove and the sealing seat 2 901 are arranged back to back, and a concave seal is arranged in the sealing groove, and the lower end of the mechanical seal assembly is sealed against the sealing seat 2 901.

[0023] The mechanical seal assembly includes two dynamic seals 17 and a static seal 18. An elastic member 20 is fixedly connected between the two dynamic seals 17. The two static seals 18 are respectively sealed and fixed to the seal seat 103 and the seal seat 2 901. The two dynamic seals 17 are respectively sealed and fixed to the rotating shaft 4. The end faces of the dynamic seals 17 and the static seals 18 are sealed. The elastic member 20 can be a single helical spring or a double helical spring. The dynamic seal 17 protrudes with a spring seat 1701. The double helical spring is fixedly sleeved on the spring seat 1701. The double helical spring is arranged parallel to the axial direction of the rotating shaft 4. The inner and outer layers of the double helical spring are parallel to the rotating shaft 4. The double helical spring enables the dynamic seal 17 and the static seal 18 to better maintain stability, increases the sealing effect of the dynamic seal 17 and the static seal 18, and improves the service life of the mechanical seal assembly.

[0024] An energy storage component 21 is fixedly connected between the oil storage portion 101 and the oil cylinder cover 9. The energy storage component 21 is elastic, and an energy storage cavity 22 is formed between the energy storage component 21 and the oil cylinder cover 9. The energy storage component 21 and the energy storage cavity 22 can store and release pressure energy. When the pressure in the oil storage cavity 10 decreases, the stored energy is released to supplement the pressure, so as to keep the pressure of the end face seal between the dynamic seal 17 and the static seal 18 stable, avoid seal failure due to pressure fluctuation, and thus extend the service life of the mechanical seal assembly. During the start-up and stop stages of the variable frequency pump, the speed changes greatly, and the energy storage structure can effectively buffer the influence of pressure fluctuation on the mechanical seal assembly. The upper end of the oil cylinder cover 9 protrudes upward with coaxial circular ring block 1 902 and circular ring block 2 903. The energy storage component 21 includes a flat ring portion and a first sealing fixed portion 2101 and a second sealing fixed portion 2102 protruding downward along the inner and outer sides of the flat ring portion. The end of the first sealing fixed portion 2101 includes an integrally formed fixed sealing ring 2103. The first sealing fixed portion 2101 is sleeved on the outer side of the circular ring block 1 902 and fixed by the oil storage portion 101 and the oil cylinder cover 9. The second sealing fixed portion 2102 is fixed by the oil cylinder cover 9 and the fixing member. The first sealing fixed portion 2101 is sleeved on the outer side of the circular ring block 1 902 and fixed by the oil storage portion 101 and the oil cylinder cover 9. Combined with the integrally formed fixed sealing ring 2103, it can effectively prevent oil leakage and improve the sealing effect; the second sealing fixed portion 2102 is fixed by the oil cylinder cover 9 and the fixing member, which enhances the connection strength between the energy storage component 21 and the oil cylinder cover 9 and ensures the stability and durability of the overall structure.

[0025] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope defined by the claims of the present invention.

Claims

1. A variable frequency pump, comprising a motor housing (1), wherein a stator (2) and a rotor (3) are arranged in the motor housing (1), a rotating shaft (4) is fixedly connected to the middle of the rotor (3), and an impeller (5) is fixedly connected to the lower part of the rotating shaft (4), characterized in that: The upper portion of the motor housing (1) is fixedly connected to an upper cap (6), a fixing seat (7) is fixedly connected between the upper cap (6) and the motor housing (1), a frequency conversion component (8) is fixedly connected between the fixing seat (7) and the upper cap (6), the lower portion of the motor housing (1) is fixedly connected to an oil cylinder cover (9), an oil storage portion (101) is integrally formed at the lower portion of the motor housing (1), an oil storage chamber (10) is provided between the oil storage portion (101) and the oil cylinder cover (9), a mechanical seal assembly is provided in the oil storage chamber (10), the lower portion of the oil cylinder cover (9) is fixedly connected to a pump housing (11), a portion between the lower end of the oil cylinder cover (9) and the pump housing (11) is provided with a seal assembly. A pump chamber (12) is formed between the fixing seat (7) and the impeller (5), the impeller (5) being located in the pump chamber (12); a bearing seat (701) protruding downward from the fixing seat (7); a bearing seat (13) being arranged in the bearing seat (701); a wave washer (14) being arranged between the upper end of the bearing (13) and the bearing seat (701); a bearing seat (102) protruding upward from the upper portion of the oil storage portion (101); a bearing seat (15) being arranged in the bearing seat (102); the upper portion of the rotating shaft (4) being fixed to the bearing seat (13), the middle portion being fixed to the bearing seat (15), and the lower portion being fixed to the impeller (5) after passing through a mechanical seal assembly.

2. A variable frequency pump according to claim 1, characterized in that: A control seat (16) is fixedly connected to the middle of the inner wall of the upper cap (6), and the control seat (16) comprises an integrally formed circular fixing plate (1601) and a downwardly protruding annular heat dissipation wall (1602), wherein the annular heat dissipation wall (1602) is tightly fitted to the inner wall of the upper cap (6), and the frequency conversion component (8) is fixedly connected to the circular fixing plate (1601).

3. A variable frequency pump according to claim 1 or 2, characterized in that: The oil storage portion (101) and the oil storage chamber (10) are both conical in shape; a sealing seat 1 (103) is provided at the upper portion of the oil storage portion (101) facing away from the bearing seat 2 (102); the upper end of the mechanical seal assembly is sealed against the sealing seat 1 (103); the upper portion of the oil cylinder cover (9) is provided with a sealing seat 2 (901); the lower end of the mechanical seal assembly is sealed against the sealing seat 2 (901).

4. A variable frequency pump according to claim 3, characterized in that: The mechanical seal assembly comprises two dynamic seals (17) sealed and fixed to the rotating shaft (4) and a static seal (18) sealed and fixed to the sealing seat 1 (103) and the sealing seat 2 (901) respectively, and an elastic member (20) is arranged between the two dynamic seals (17).

5. A variable frequency pump according to claim 4, characterized in that: The elastic member (20) is a double helical spring, the dynamic seal (17) protrudes with a spring seat (1701), the double helical spring is fixedly sleeved on the spring seat (1701), and the double helical spring is arranged parallel to the axial direction of the rotating shaft (4).

6. A variable frequency pump according to claim 3, characterized in that: An energy storage component (21) is fixedly connected between the oil storage portion (101) and the oil cylinder cover (9); the energy storage component (21) is elastic, and an energy storage cavity (22) is formed between the energy storage component (21) and the oil cylinder cover (9).

7. A variable frequency pump according to claim 6, characterized in that: The upper end of the oil cylinder cover (9) is provided with a coaxial circular ring block 1 (902) and a circular ring block 2 (903) protruding upward, and the energy storage component (21) comprises a flat ring portion and a first sealing fixing portion (2101) and a second sealing fixing portion (2102) protruding downward along the inner and outer sides of the flat ring portion, and the end of the first sealing fixing portion (2101) comprises an integrally formed fixed sealing ring (2103), the first sealing fixing portion (2101) is sleeved on the outer side of the circular ring block 1 (902) and fixed by the oil storage portion (101) and the oil cylinder cover (9), and the second sealing fixing portion (2102) is fixed by the oil cylinder cover (9) and the fixing component.

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