Patent Description:
A magnetic suspension motor mainly includes a housing, a stator provided in the housing and fixedly connected with the housing, a rotating shaft provided in the stator, a radial magnetic suspension bearing for supporting the rotating shaft to rotate, and an axial thrust bearing for keeping an axial position of the rotating shaft. The magnetic suspension motor further includes a protective bearing provided in the housing, and the protective bearing is configured to bear the static rotating shaft. When the magnetic suspension motor works, the radial magnetic suspension bearing is electrified to separate the rotating shaft from the protective bearing and suspend the rotating shaft.

A magnetic suspension pump includes the magnetic suspension motor and a pump driven by the magnetic suspension motor. When the magnetic suspension pump is powered off, the rotating shaft rotating at a high speed loses buoyancy and impacts the protective bearing, and the protective bearing is prone to damage. <CIT> discloses a seal assembly for a compressor including at least one impeller. At least one seal land is associated with the impeller including a plurality of radially stepped surfaces. A seal is associated with each of at least one seal lands. The seal includes a plurality of radially stepped projections corresponding to the plurality of radially stepped surfaces on at least one seal land. At least one actuator is configured to move at least one seal land relative to the seal.

An object of the present invention is to overcome at least one technical defect of a prior art, and solve a problem that a protective bearing of an existing magnetic suspension pump is prone to damage by an impact of a rotating shaft when a magnetic suspension motor is powered off.

A further object of the present invention is to prolong a service life of a first sealing ring and/or a second sealing ring.

The present invention is defined by the magnetic suspension pump of claim <NUM>, the refrigeration device of claim <NUM> and the air conditioner outdoor unit of claim <NUM>. In the following, in case parts of the description and drawing referring to embodiments, which are not covered by the claims are not presented as embodiments of the invention, but as examples useful for understanding the invention.

In order to achieve the above objects, the present invention provides a magnetic suspension pump, including:.

Optionally, the buffering member is a buffering ring having an annular structure, and the buffering ring is provided between the first sealing ring and the pump housing along a radial direction of the first sealing ring; an inner circumferential surface of the buffering ring abuts against the first sealing ring, and an outer circumferential surface of the buffering ring abuts against the pump housing.

Optionally, the buffering member is a spring, and the spring is provided between the first sealing ring and the pump housing along the axial direction of the first sealing ring; the spring has one axial end connected with the first sealing ring and the other axial end connected with the pump housing.

Optionally, the spring abuts against the first sealing ring and the pump housing, and at least one spring abuts against each of two axial ends of the first sealing ring.

Optionally, the first sealing ring is an annular sleeve; the second sealing ring is an annular tooth, and the annular tooth has a wedge-shaped section.

Optionally, the first sealing ring has a smaller hardness than the second sealing ring.

Optionally, the pump is a centrifugal pump.

Furthermore, the present invention provides a refrigeration device including the magnetic suspension pump according to any one of the above-mentioned technical solutions.

Further, the present invention provides an air conditioner outdoor unit including the magnetic suspension pump according to any one of the above-mentioned technical solutions.

Based on the foregoing description, it can be understood by those skilled in the art that, in the foregoing technical solution of the present invention, by providing the first sealing ring on the pump housing, providing the second sealing ring on the impeller, matching the first sealing ring with the second sealing ring, and scratching the annular groove on one of the first sealing ring and the second sealing ring by the other, the pump housing and the impeller can be dynamically sealed by the first sealing ring and the second sealing ring, and meanwhile, the impeller can freely rotate relative to the pump housing by means of the annular groove.

It can also be appreciated by those skilled in the art that since the annular groove is scratched by the first sealing ring or the second sealing ring (specifically, when the impeller rotates), a gap between the first sealing ring and the second sealing ring is small. Therefore, when the motor is powered off, the first sealing ring and the second sealing ring can come into contact firstly, and then, the rotating shaft comes into contact with the protective bearing. When the first sealing ring and the second sealing ring contact each other, kinetic energy and momentum of the rotating shaft can be absorbed, thereby reducing the impact of the rotating shaft on the protective bearing, and effectively avoiding a risk of damage to the protective bearing.

Further, by providing the buffering member between the first sealing ring and the motor housing and/or the pump housing, and/or providing the buffering member between the second sealing ring and the impeller, when the impeller moves along the axial direction of the first sealing ring, the first sealing ring or the second sealing ring can move along with the impeller by virtue of deformation of the buffering member, a side wall of the annular groove is prevented from being continuously scratched by the first sealing ring or the second sealing ring, and then, a width of the annular groove is prevented from being increased, and the annular groove can maintain a small width, thereby guaranteeing the gap between the first sealing ring and the second sealing ring, and prolonging the service life of the first sealing ring and/or the second sealing ring.

Further, by configuring the first sealing ring as the annular tooth, the width of the annular groove can be sufficiently small, thereby reducing an amount of outward leakage of fluid in the pump housing.

Still further, by configuring the first sealing ring to include the first axial sealing ring and the first radial sealing ring and configuring the second sealing ring to include the second axial sealing ring and the second radial sealing ring, the first axial sealing ring and the second axial sealing ring can absorb an axial impact force when the rotating shaft is powered off and limit an axial displacement of the rotating shaft, the first radial sealing ring and the second radial sealing ring can absorb a radial impact force when the rotating shaft is powered off and limit a radial displacement of the rotating shaft, and therefore, the rotating shaft can be prevented from deflecting.

According to the following detailed description of specific embodiments of the present invention in conjunction with drawings, those skilled in the art will better understand the aforementioned and other objects, advantages and features of the present invention.

In order to more clearly explain the technical solution of the present invention, some embodiments of the present invention will be described hereinafter with reference to the accompanying drawings. Those skilled in the art should appreciate that components or parts with the same reference numerals are the same or similar in different drawings; the drawings of the present invention are not necessarily drawn to scale relative to each other. In the drawings:.

Reference is now made in detail to embodiments of the present invention, one or more examples of which are shown in the drawings. The embodiments are provided to explain the present invention and not to limit it. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the present invention. Therefore, it is intended that the present invention covers the modifications and variations within the scope of the appended claims and their equivalents.

It should be understood by those skilled in the art that the embodiments described below are only some embodiments of the present invention and not all embodiments of the present invention, and the embodiments are intended to explain the technical principle of the present invention and not to limit the scope of the present invention. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

It should be noted that, in the description of the present invention, directions or positional relationships indicated by terms "center", "upper", "lower", "top", "bottom", "left", "right", "vertical", "horizontal", "inner", "outer" etc. are based on directions or positional relationships shown in the drawings, and they are used only for facilitating the description, but do not indicate or imply that a described apparatus or element must have a specific orientation or be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention. In addition, the terms such as "first", "second" and "third" are merely used for purposes of description and are not intended to indicate or imply relative importance.

Furthermore, it should also be noted that, in the description of the present invention, unless specified or limited otherwise, the terms "mounted", "connected", "coupled" and the like are used broadly, and may be, for example, fixed connections, detachable connections, or integral connections; may also be mechanical or electrical connections; may also be direct connections or indirect connections via intervening structures; may also be inner communications of two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

<FIG> is a sectional view of a magnetic suspension pump according to some embodiments of the present invention, <FIG> is an enlarged view of portion A of <FIG>, <FIG> is an enlarged view of portion B of <FIG>, and <FIG> is an enlarged view of portion C of <FIG>.

As shown in <FIG>, in some embodiments of the present invention, the magnetic suspension pump includes a motor <NUM> and a pump <NUM>. Preferably, the magnetic suspension pump includes two pumps <NUM>, and the two pumps <NUM> are provided at two axial ends of the motor <NUM> respectively. Furthermore, those skilled in the art can also configure only one pump <NUM> for the magnetic suspension pump as required; that is, the pump <NUM> at the left or right of the motor <NUM> in <FIG> is omitted. Or, those skilled in the art may also connect at least two pumps <NUM> in series on the left or right side of the motor <NUM> as required.

With continued reference to <FIG>, the motor <NUM> includes a motor housing <NUM>, a rotating shaft <NUM>, a radial magnetic suspension bearing <NUM>, an axial magnetic suspension bearing <NUM>, and a protective bearing <NUM>. The rotating shaft <NUM> is rotatably provided in the motor housing <NUM>, and the radial magnetic suspension bearing <NUM>, the axial magnetic suspension bearing <NUM> and the protective bearing <NUM> are fixedly provided inside the motor housing <NUM>.

When the motor <NUM> is powered on, gaps exist between the radial magnetic suspension bearing <NUM> and the rotating shaft <NUM>, the axial magnetic suspension bearing <NUM> and the rotating shaft <NUM>, and the protective bearing <NUM> and the rotating shaft <NUM>. A radial gap between the radial magnetic suspension bearing <NUM> and the rotating shaft <NUM> is greater than a radial gap between the protective bearing <NUM> and the rotating shaft <NUM>; a radial gap between the axial magnetic suspension bearing <NUM> and the rotating shaft <NUM> is greater than the radial gap between the protective bearing <NUM> and the rotating shaft <NUM>, such that in a power-off state of the motor <NUM>, the rotating shaft <NUM> abuts against the protective bearing <NUM> and does not contact the radial magnetic suspension bearing <NUM> and/or the axial magnetic suspension bearing <NUM>.

With continued reference to <FIG>, the rotating shaft <NUM> is provided with a thrust disc <NUM>, and one axial magnetic suspension bearing <NUM> is provided on each of two sides of the thrust disc <NUM>. When the motor <NUM> is energized, gaps exist between the thrust disc <NUM> and the two axial magnetic suspension bearings <NUM>.

It should be noted that, in the present invention, each of the radial magnetic suspension bearing <NUM> and the axial magnetic suspension bearing <NUM> includes a coil and/or a member capable of generating a magnetic force when energized. Since the radial magnetic suspension bearing <NUM> and the axial magnetic suspension bearing <NUM> are common parts in the art and are commercially available, they are not explained too much in the present disclosure.

With continued reference to <FIG>, the pump <NUM> includes a pump housing <NUM> and an impeller <NUM>. The pump housing <NUM> and the motor housing <NUM> are fixedly connected or integrally manufactured, and the impeller <NUM> is coaxially and fixedly connected with the rotating shaft <NUM>. The rotating shaft <NUM> drives the impeller <NUM> to rotate synchronously when rotating. Further, the pump housing <NUM> is provided with an inlet <NUM> and an outlet <NUM>. The rotating impeller <NUM> creates a negative pressure within the pump housing <NUM>, thereby forcing ambient fluid into the pump housing <NUM> from the inlet <NUM> and forcing fluid within the pump housing <NUM> out of the pump housing <NUM> from the outlet <NUM>.

Although not shown in the drawings, in some embodiments of the present invention, the pump <NUM> is a centrifugal pump and the impeller <NUM> is a centrifugal impeller. Certainly, those skilled in the art can also configure the pump <NUM> as a plunger pump, a gear pump, a vane pump, a rotor pump or other pumps in any form in other embodiments of the present invention as required.

With continued reference to <FIG>, the pump housing <NUM> includes an inner volute <NUM> and an outer volute <NUM>. The inner volute <NUM> and the outer volute <NUM> are fixedly connected together by screws or bolts, and the inner volute <NUM> and the motor housing <NUM> are fixedly connected together by screws or bolts.

As shown in <FIG>, in some embodiments of the present invention, the magnetic suspension pump further includes a first sealing ring <NUM>, a second sealing ring <NUM> and a buffering member <NUM>. The first sealing ring <NUM> and the second sealing ring <NUM> are matched with each other, the first sealing ring <NUM> is provided on the motor housing <NUM> and/or the pump housing <NUM>, the second sealing ring <NUM> is provided on the impeller <NUM>, and when the second sealing ring <NUM> rotates, an annular groove <NUM> is scratched on the first sealing ring <NUM> or by the first sealing ring <NUM>. The buffering member <NUM> is provided between the first sealing ring <NUM> and the motor housing <NUM> and/or the pump housing <NUM>, and the buffering member <NUM> can deform along an axial direction of the first sealing ring <NUM>; and/or the buffering member <NUM> is provided between the second sealing ring <NUM> and the impeller <NUM>, and the buffering member <NUM> can deform along an axial direction of the second sealing ring <NUM>.

Furthermore, those skilled in the art can also provide the first sealing ring <NUM> on the impeller <NUM> and provide the second sealing ring <NUM> on the pump housing <NUM> as required.

Further, those skilled in the art may also provide a buffering member <NUM> between the second sealing ring <NUM> and the pump housing <NUM>, or provide the buffering member <NUM> only between the second sealing ring <NUM> and the pump housing <NUM> as required.

Preferably, as shown in <FIG>, the first sealing ring <NUM> includes a first radial sealing ring <NUM> and a first axial sealing ring <NUM>, the second sealing ring <NUM> includes a second radial sealing ring <NUM> and a second axial sealing ring <NUM>, the first radial sealing ring <NUM> is matched with the second radial sealing ring <NUM>, and the first axial sealing ring <NUM> is matched with the second axial sealing ring <NUM>.

Further preferably, as shown in <FIG>, the inner volute <NUM> and the outer volute <NUM> are provided with the first radial sealing ring <NUM> and the first axial sealing ring <NUM> respectively. Furthermore, those skilled in the art may also provide the first radial sealing ring <NUM> and the first axial sealing ring <NUM> only on the inner volute <NUM> or the outer volute <NUM> as required; or, the first radial sealing ring <NUM> is provided on one of the inner volute <NUM> and the outer volute <NUM>, and the first axial sealing ring <NUM> is provided on the other of the inner volute <NUM> and the outer volute <NUM>.

As can be seen from the drawings, a plurality of second radial sealing rings <NUM> and a plurality of second axial sealing rings <NUM> are provided, such that the first radial sealing ring <NUM> corresponds to the plurality of second radial sealing rings <NUM>, and the first axial sealing ring <NUM> corresponds to the plurality of second axial sealing rings <NUM>. It can be appreciated by those skilled in the art that the correspondence of the first sealing ring <NUM> to a plurality of second sealing rings <NUM> can reduce stress between the second sealing rings <NUM> and the first sealing ring <NUM>, so as to prevent the second sealing rings <NUM> and the first sealing ring <NUM> from excessively abrading each other. Furthermore, the correspondence of the first sealing ring <NUM> to the plurality of second sealing rings <NUM> can form multiple seals between the second sealing rings <NUM> and the first sealing ring <NUM>, thereby preventing leakage of the fluid in the pump housing <NUM>.

Although not shown in the drawings, the first sealing ring <NUM> is an annular sleeve, or the first sealing ring <NUM> is composed of a plurality of semi-annular structures. That is, the first radial sealing ring <NUM> and/or the first axial sealing ring <NUM> are annular sleeves, or the first sealing ring <NUM> is composed of the plurality of semi-annular structures.

Further, although not shown in the drawings, the second sealing ring <NUM> is an annular tooth; that is, both the second radial sealing ring <NUM> and the second axial sealing ring <NUM> are annular teeth. Preferably, the annular tooth has a wedge-shaped section (as shown in <FIG>).

Preferably, the second radial sealing ring <NUM> and the second axial sealing ring <NUM> are integrally formed on the impeller <NUM>. Or, those skilled in the art may also fix the second radial sealing ring <NUM> and the second axial sealing ring <NUM> to the impeller <NUM> by a threaded connection, welding, interference fit, screw connection, or the like, and selectively provide the buffering member <NUM> between the second radial sealing ring <NUM> and the impeller <NUM> and/or between the second axial sealing ring <NUM> and the impeller <NUM>, as required.

Further, in some embodiments of the present invention, a hardness of the first sealing ring <NUM> is smaller than a hardness of the second sealing ring <NUM>, such that the second sealing ring <NUM> can scratch a shallow scratch, i.e., the annular groove <NUM>, on the first sealing ring <NUM> when rotating with the impeller <NUM> (as shown in <FIG>).

In order to achieve the above object, the first sealing ring <NUM> in the present invention may be made of any feasible material, such as epoxy resin, phenolic resin, or the like.

Preferably, when the magnetic suspension pump according to the present invention is assembled, the first sealing ring <NUM> and the second sealing ring <NUM> are in transition fit. When the magnetic suspension pump is energized, the rotating shaft <NUM> drives the impeller <NUM> and the second sealing ring <NUM> to rotate, and a circumferential edge of the rotating second sealing ring <NUM> scratches the shallow scratch, i.e., the annular groove <NUM>, on the first sealing ring <NUM> (as shown in <FIG>).

It can be appreciated by those skilled in the art that since the annular groove <NUM> on the first sealing ring <NUM> is scratched by the rotating second sealing ring <NUM>, a gap between the first radial sealing ring <NUM> and the second radial sealing ring <NUM> and a gap between the first axial sealing ring <NUM> and the second axial sealing ring <NUM> are sufficiently small (even <NUM> in some regions). In other words, the annular groove <NUM> is created to accommodate operation of the magnetic suspension pump, which not only saves a production cost, but also allows the second sealing ring <NUM> to be sufficiently tightly fitted with the first sealing ring <NUM> to achieve a good sealing effect on the pump <NUM>, as compared to an annular groove machined by mechanical equipment.

Based on the foregoing description, it can be understood by those skilled in the art that, in the present invention, the annular groove <NUM> is scratched on the first sealing ring <NUM> during the rotation of the second sealing ring <NUM>, such that a pressure generated when the first sealing ring <NUM> comes into contact with the second sealing ring <NUM> is almost zero, and therefore, the second sealing ring <NUM>, the impeller <NUM> and the rotating shaft <NUM> can rotate freely relative to the first sealing ring <NUM>. Therefore, the first sealing ring <NUM> and the second sealing ring <NUM> of the present invention also improve a sealing performance of the pump <NUM> and prevent leakage (including external leakage and internal leakage) of the fluid compressed in the pump <NUM> on the premise of guaranteeing low resistance operation of the magnetic suspension pump.

Further, in the present invention, by configuring the first sealing ring <NUM> to include the first radial sealing ring <NUM> and the first axial sealing ring <NUM> and configuring the second sealing ring <NUM> to include the second radial sealing ring <NUM> and the second axial sealing ring <NUM>, the first radial sealing ring <NUM> and the second radial sealing ring <NUM> can absorb a radial impact force when the rotating shaft <NUM> is powered off and limit a radial displacement of the rotating shaft <NUM>, the first axial sealing ring <NUM> and the second axial sealing ring <NUM> can absorb an axial impact force when the rotating shaft <NUM> is powered off and limit an axial displacement of the rotating shaft <NUM>, and therefore, the rotating shaft <NUM> can be prevented from deflecting.

Furthermore, in other embodiments of the present invention, those skilled in the art may provide only the first radial sealing ring <NUM> and the second radial sealing ring <NUM>, or only the first axial sealing ring <NUM> and the second axial sealing ring <NUM>, on the pump <NUM> as required.

As shown in <FIG>, in some embodiments of the present invention, the buffering member <NUM> is a buffering ring <NUM> having an annular structure. The buffering ring <NUM> is provided between the first sealing ring <NUM> and the pump housing <NUM> in the radial direction of the first sealing ring <NUM>. An inner circumferential surface of the buffering ring <NUM> abuts against the first sealing ring <NUM>, and an outer circumferential surface of the buffering ring <NUM> abuts against the pump housing <NUM>.

Specifically, at least one buffering ring <NUM> is provided between the first radial sealing ring <NUM> and the pump housing <NUM>, and at least one buffering ring <NUM> is provided between the first axial sealing ring <NUM> and the pump housing <NUM>. Or, those skilled in the art may provide the buffering ring <NUM> only between the first radial sealing ring <NUM> and the pump housing <NUM>, or only between the first axial sealing ring <NUM> and the pump housing <NUM>, as required.

Further, in some embodiments of the present invention, the buffering ring <NUM> is made of an elastic material, such that the buffering ring <NUM> can be deformed along the axial direction and/or the radial direction of the first sealing ring <NUM>. The elastic material may be any feasible material, such as rubber, silicone, plastic, or the like.

Next, the deformation of the buffering ring <NUM> will be described in detail with reference to <FIG> is a schematic diagram of an effect of the buffering member in some embodiments of the present invention when the impeller is radially offset, and <FIG> is a schematic diagram of an effect of the buffering member in some embodiments of the present invention when the impeller is axially offset.

As shown in <FIG>, when the impeller <NUM> moves radially from a normal rotation position (position coaxial with the protective bearing <NUM>) in a direction indicated by the arrow in <FIG>, the second radial sealing ring <NUM> presses the first radial sealing ring <NUM> in the radial direction thereof, and therefore, the first radial sealing ring <NUM> presses the corresponding buffering ring <NUM> in the direction indicated by the arrow in <FIG>, thereby deforming (i.e., thinning) a corresponding part of the buffering ring <NUM> in the radial direction. Meanwhile, the second axial sealing ring <NUM> presses the first axial sealing ring <NUM> in the axial direction thereof (specifically, a circumferential edge of the second axial sealing ring <NUM> presses the side wall of the annular groove <NUM> on the first axial sealing ring <NUM>), and therefore, the first axial sealing ring <NUM> presses the corresponding buffering ring <NUM> in the direction indicated by the arrow in <FIG>, thereby deforming a corresponding part of the buffering ring <NUM> in the axial direction.

As shown in <FIG>, when the impeller <NUM> moves axially from the normal rotation position in a direction indicated by the arrow in <FIG>, the second radial sealing ring <NUM> presses the first radial sealing ring <NUM> in the axial direction thereof (specifically, a circumferential edge of the second radial sealing ring <NUM> presses the side wall of the annular groove <NUM> on the first radial sealing ring <NUM>), and therefore, the first radial sealing ring <NUM> presses the corresponding buffering ring <NUM> in the direction indicated by the arrow in <FIG>, thereby deforming a corresponding part of the buffering ring <NUM> in the axial direction. Meanwhile, the second axial sealing ring <NUM> presses the first axial sealing ring <NUM> in the radial direction thereof, and therefore, the first axial sealing ring <NUM> presses the corresponding buffering ring <NUM> in the direction indicated by the arrow in <FIG>, thereby deforming and thus thinning a corresponding part of the buffering ring <NUM> in the radial direction.

Based on the foregoing description, it can be understood by those skilled in the art that due to the arrangement of the buffering ring <NUM>, when the impeller <NUM> moves along the radial direction or the axial direction thereof, the first radial sealing ring <NUM> and the first axial sealing ring <NUM> can move together with the impeller <NUM> by means of the deformation of the buffering member <NUM>, the side walls of the annular grooves <NUM> on the second radial sealing ring <NUM> and the second axial sealing ring <NUM> are prevented from being further scratched by the first radial sealing ring <NUM> and the first axial sealing ring <NUM>, and a width of the annular groove <NUM> is prevented from being increased, such that the annular groove <NUM> can maintain a small width, thereby guaranteeing the gap between the first sealing ring <NUM> and the second sealing ring <NUM>, and prolonging a service life of the first sealing ring <NUM>.

It can also be understood by those skilled in the art that since the buffering ring <NUM> can absorb impacts of the rotating shaft <NUM> and the impeller <NUM> during the deformation, the buffering ring <NUM> can reduce an impact of the rotating shaft <NUM> on the protective bearing <NUM>, thereby prolonging a service life of the protective bearing <NUM>.

<FIG> is a schematic diagram of the effect of the buffering member in some other embodiments of the present invention.

In some other embodiments of the present invention, as shown in <FIG>, the buffering member <NUM> is a spring <NUM>, the spring <NUM> is provided between the first sealing ring <NUM> and the pump housing <NUM> in the axial direction of the first sealing ring <NUM>, and one axial end of the spring <NUM> is connected with the first sealing ring <NUM> and the other axial end of the spring <NUM> is connected with the pump housing <NUM>. The connection may be a hook connection or abutment.

Specifically, the spring <NUM> abuts against the first sealing ring <NUM> and the pump housing <NUM>, and at least one spring <NUM> abuts against each of two axial ends of the first sealing ring <NUM>.

More specifically, one spring <NUM> abuts against each of two axial ends of the first radial sealing ring <NUM>, and the end of the spring <NUM> apart from the first radial sealing ring <NUM> abuts against the pump housing <NUM>. One spring <NUM> abuts against each of two axial ends of the first axial sealing ring <NUM>, and the end of the spring <NUM> apart from the first axial sealing ring <NUM> abuts against the pump housing <NUM>. Or, those skilled in the art may configure only one spring <NUM> for the first radial sealing ring <NUM> and/or the first axial sealing ring <NUM>, fixedly connect one end of the spring <NUM> to the first radial sealing ring <NUM> and/or the first axial sealing ring <NUM>, and fixedly connect the other end of the spring <NUM> to the pump housing <NUM>, as required.

Preferably, the first radial sealing ring <NUM> is slidable relative to the pump housing <NUM> in the axial direction thereof, and the first axial sealing ring <NUM> is also slidable relative to the pump housing <NUM> in the axial direction thereof.

Further, when the impeller <NUM> is radially offset from a working position (where a rotation center of the impeller is coaxial with a rotation center of the protective bearing <NUM>), the second axial sealing ring <NUM> presses the first axial sealing ring <NUM> in the axial direction thereof (specifically, the circumferential edge of the second axial sealing ring <NUM> presses the side wall of the annular groove <NUM> on the first axial sealing ring <NUM>), and therefore, the first axial sealing ring <NUM> presses the corresponding spring <NUM> to compress the spring <NUM>.

When the impeller <NUM> is axially offset from the working position, the second radial sealing ring <NUM> presses the first radial sealing ring <NUM> in the axial direction thereof (specifically, the circumferential edge of the second radial sealing ring <NUM> presses the side wall of the annular groove <NUM> on the first radial sealing ring <NUM>), and therefore, the first radial sealing ring <NUM> presses the corresponding spring <NUM> to compress the spring <NUM>.

Furthermore, in other embodiments of the present invention, those skilled in the art may configure the buffering member <NUM> as any other feasible structure as required, for example, a plurality of arc-shaped plate-like members which are provided between the first sealing ring <NUM> and the pump housing <NUM> in the radial direction of the first sealing ring <NUM>. An inner circumferential surface of each plate-like member abuts against the first sealing ring <NUM> and an outer circumferential surface of each plate-like member abuts against the pump housing <NUM>.

Further, although not shown in the drawings, still further embodiments of the present invention further provide a refrigeration device including the magnetic suspension pump according to any one of the foregoing embodiments. In these embodiments of the present invention, the magnetic suspension pump is used as a compressor of the refrigeration device for compressing a refrigerant. The refrigeration device includes a refrigerator, a freezer and/or a cooler.

Claim 1:
A magnetic suspension pump, comprising:
a magnetic suspension motor (<NUM>) comprising a motor housing (<NUM>) and a rotating shaft (<NUM>);
a pump (<NUM>) comprising a pump housing (<NUM>) and an impeller (<NUM>), the pump housing (<NUM>) and the motor housing (<NUM>) being fixedly connected or integrally formed, and the impeller (<NUM>) being coaxially and fixedly connected with the rotating shaft (<NUM>);
a first sealing ring (<NUM>) provided on the motor housing (<NUM>) and/or the pump housing (<NUM>);
a second sealing ring (<NUM>) provided on the impeller (<NUM>) and matched with the first sealing ring (<NUM>), when the second sealing ring (<NUM>) rotates, an annular groove being scratched on the first sealing ring (<NUM>) or by the first sealing ring (<NUM>); and
a buffering member (<NUM>), wherein the buffering member (<NUM>) is provided between the first sealing ring (<NUM>) and the motor housing (<NUM>) and/or the pump housing (<NUM>), and the buffering member (<NUM>) can deform along an axial direction of the first sealing ring (<NUM>); and/or, the buffering member (<NUM>) is provided between the second sealing ring (<NUM>) and the impeller (<NUM>), and the buffering member (<NUM>) can deform along an axial direction of the second sealing ring (<NUM>);
characterized in that
the first sealing ring (<NUM>) comprises a first axial sealing ring (<NUM>) and a first radial sealing ring (<NUM>);
the second sealing ring (<NUM>) comprises a second axial sealing ring (<NUM>) and a second radial sealing ring (<NUM>);
the first axial sealing ring (<NUM>) is matched with the second axial sealing ring (<NUM>);
the first radial sealing ring (<NUM>) is matched with the second radial sealing ring (<NUM>); and
each of the first axial sealing ring (<NUM>) and the first radial sealing ring (<NUM>) corresponds to the buffering member (<NUM>);
the first axial sealing ring (<NUM>) and the second axial sealing ring (<NUM>) absorb an axial impact force when the rotating shaft (<NUM>) is powered off and limit an axial displacement of the rotating shaft (<NUM>), the first radial sealing ring (<NUM>) and the second radial sealing ring (<NUM>) absorb a radial impact force when the rotating shaft (<NUM>) is powered off and limit a radial displacement of the rotating shaft (<NUM>).