Summary of the invention
The main purpose of the present invention is to provide a kind of electric expansion valve and with its refrigeration system, to solve existing skill
Electric expansion valve in art while increasing flow-control scope, be unable to reach high-precision, miniaturization requirement the problem of.
To achieve the goals above, according to an aspect of the invention, there is provided a kind of electric expansion valve, comprising: valve seat,
With cavity and the valve port portion being connected to cavity;Needle is movably disposed in cavity, and needle, which has, opens valve port portion
The closed position in open position and close port portion;Driving mechanism, including coil and rotor;Planetary gear reducing mechanism,
Including output shaft, input terminal of the driving mechanism as planetary gear reducing mechanism, planetary gear reducing mechanism includes sun gear, row
Carrier, planetary gear and the sleeve for being fixedly installed on valve seat, sun gear, planet carrier and sleeve coaxial arrangement, planet carrier setting
There is the first installation axle, planetary gear is sheathed on the first installation axle, and sun gear is rotated by driving mechanism, sun wheel drive row
Star-wheel carries out rotation along planetary gear own axes, and the inner wall of sleeve is provided with internal gear, and planetary gear is engaged with internal gear so that more
A planetary gear revolves along the axis of sleeve to drive planet carrier around own axes rotation, and output shaft is formed in planet carrier;Driver
Structure, output shaft are moved along a straight line by transmission mechanism valve needle, so that needle moves between an open position and a closed.
Further, the first installation axle is the one or more being arranged along the circumferential direction of planet carrier, and planetary gear is and the
The one or more that one installation axle is arranged in a one-to-one correspondence.
Further, planet carrier further includes at least two second installation axles and is arranged in a one-to-one correspondence with the second installation axle
At least two muscle positions, each muscle position are wrapped in the outer circumferential of each second installation axle, and the first installation axle is set with the second installation axle interval
It sets, planetary gear reducing mechanism further includes cover board, and cover board is provided with the mounting hole with the first installation axle and the cooperation of the second installation axle,
The bottom surface of cover board is abutted with the top surface of muscle position.
Further, sun gear is set to rotor.
Further, rotor has roof and side wall, and roof and side wall surround first receiving space, and sun gear is set to
The inside of roof simultaneously extends downwardly, and at least partly planetary gear reducing mechanism is contained in first receiving space.
Further, electric expansion valve further include: shell covers at the top of valve seat, and interior of shell has second to accommodate
Space, planetary gear reducing mechanism and transmission mechanism are arranged in the second accommodation space.
Further, it is fixedly installed upper frame structure in shell, planetary gear reducing mechanism further includes mandrel, and mandrel is from upper
It is successively threaded through in upper frame structure, sun gear and planet carrier under, wherein the axis of mandrel and the axis of sun gear and planet carrier
Axis collinear.
Further, electric expansion valve includes multi-level planet gear speed reducer structure, afterbody planetary gear reducing mechanism
Planetary gear output shaft and transmission mechanism cooperate, upper level planet-gear speed reducer in adjacent two-stage planet deceleration mechanism
The outer wall of the output shaft of structure is provided with external gear, and the output shaft with external gear forms next stage planetary gear reducing mechanism too
The planetary gear of sun wheel, external gear and next stage planetary gear reducing mechanism cooperates, so that next stage planetary gear reducing mechanism
Planetary gear carries out rotation along planetary gear own axes.
Further, multi-level planet gear speed reducer structure shares same sleeve.
Further, output shaft is provided with mating groove, and transmission mechanism includes screw rod and the nut for being fixedly installed on valve seat,
Screw rod includes cooperation section and linkage section, and at least partly cooperation section is movably disposed in mating groove, when output shaft rotation,
The cell wall and cooperation section of mating groove cooperate so that screw rod rotation, the outer wall of linkage section are provided with external screw thread, linkage section and nut spiral shell
Line connection, is converted to linear motion for the rotational motion of screw rod.
Further, sub- expansion valve further include: valve needle cover is set on the outside of needle and is fixedly installed on valve seat, and needle can
It is movably arranged in valve needle cover, valve needle cover includes construction section and the guide section below construction section, construction section and guiding
The junction of section forms step surface, and guide section is adapted to needle;Spring is located in construction section, at the top of one end of spring and needle
Abutting protrusion abut, the other end of spring abuts with step surface, when needle is moved from closed position to open position, needle
Upward elastic-restoring force by spring.
Further, the cavity wall of cavity is provided with annular flange, and cavity is divided into the installation of installation nut by annular flange
Chamber and the overcurrent chamber below installation cavity, valve port portion are formed in the cavity wall of overcurrent chamber, are provided at the top of valve needle cover outward
The flange of extension, flange are folded between nut and the upper surface of annular flange.
According to another aspect of the present invention, a kind of refrigeration system, including electric expansion valve are provided, electric expansion valve is upper
The electric expansion valve stated.
It applies the technical scheme of the present invention, electric expansion valve includes the planetary gear reducing mechanism being arranged on valve seat, is driven
Input terminal of the motivation structure as planetary gear reducing mechanism, planetary gear reducing mechanism have output shaft, and output shaft passes through transmission
Mechanism valve needle moves along a straight line so that needle moves between an open position and a closed.Due to planet-gear speed reducer
Inside engaged gear is used in structure, takes full advantage of transmission space, therefore the bulk of entire deceleration mechanism is than identical item
Small more of spur-gear speed reducer structure under part.That is, under conditions of identical size, the deceleration of planetary gear reducing mechanism
Bigger than the reduction ratio than spur-gear speed reducer structure is more, therefore above structure makes while increasing flow-control scope,
Electric expansion valve can reach the requirement of high-precision, miniaturization, solve electric expansion valve in the prior art and increasing flow
While control range, be unable to reach high-precision, miniaturization requirement the problem of.
Detailed description of the invention
The accompanying drawings constituting a part of this application is used to provide further understanding of the present invention, and of the invention shows
Examples and descriptions thereof are used to explain the present invention for meaning property, does not constitute improper limitations of the present invention.In the accompanying drawings:
Fig. 1 shows the schematic diagram of internal structure of electric expansion valve in the prior art;
Fig. 2 shows the structural schematic diagrams of the spur-gear speed reducer structure of the electric expansion valve of Fig. 1;
Fig. 3 shows the schematic perspective view of the embodiment of electric expansion valve according to the present invention;
Fig. 4 shows the schematic diagram of internal structure of the electric expansion valve of Fig. 3;
Fig. 5 shows the enlarged structure schematic diagram at the A of the electric expansion valve of Fig. 4;
Fig. 6 shows the enlarged structure schematic diagram at the B of the electric expansion valve of Fig. 4;
Fig. 7 shows the rotor of the electric expansion valve of Fig. 4 and the structural schematic diagram of multi-level planet gear speed reducer structure cooperation;
Fig. 8 shows the rotor of the electric expansion valve of Fig. 3 and the decomposition texture schematic diagram of multi-level planet gear speed reducer structure;
Fig. 9 shows the upper level planetary gear of the adjacent two-stage planet deceleration mechanism of the electric expansion valve of Fig. 8
The decomposition texture schematic diagram of deceleration mechanism;
Figure 10 shows the next stage planetary gear of the adjacent two-stage planet deceleration mechanism of the electric expansion valve of Fig. 8
The decomposition texture schematic diagram of deceleration mechanism;
Figure 11 shows the schematic perspective view of the rotor of the electric expansion valve of Fig. 3;
Figure 12 shows the schematic diagram of internal structure of the sleeve of the electric expansion valve of Fig. 3;And
Figure 13 shows the structure diagram of the planetary gear reducing mechanism of the electric expansion valve of Fig. 3.
Wherein, the above drawings include the following reference numerals:
1, first receiving space;2, the second accommodation space;4, installation cavity;5, overcurrent chamber;6, cavity;10, valve seat;11, valve
Oral area;12, annular flange;20, needle;21, protrusion is abutted;31, coil;32, rotor;321, roof;322, side wall;40, row
Star gear reduction;41, sun gear;42, planet carrier;421, the first installation axle;422, output shaft;4221, external gear;
4222, mating groove;423, the second installation axle;424, muscle position;425, bottom plate;43, planetary gear;44, sleeve;441, internal gear;45,
Cover board;451, mounting hole;46, mandrel;50, transmission mechanism;51, screw rod;511, cooperate section;512, linkage section;52, nut;60,
Shell;70, upper frame structure;80, valve needle cover;81, construction section;811, flange;82, guide section;83, step surface;90, spring;
100, first pipe;110, second pipe.
Specific embodiment
It should be noted that in the absence of conflict, the features in the embodiments and the embodiments of the present application can phase
Mutually combination.The present invention will be described in detail below with reference to the accompanying drawings and embodiments.
As shown in Fig. 3, Fig. 4 and Fig. 7, the electric expansion valve of the present embodiment includes valve seat 10, needle 20, driving mechanism, row
Star gear reduction 40 and transmission mechanism 50.Wherein, the valve port portion 11 that valve seat 10 has cavity 6 and is connected to cavity 6.
Needle 20 is movably disposed in valve cavity 6, and needle 20 has the open position and close port portion for opening valve port portion 11
11 closed position.It should be noted that open position is the standard-sized sheet position that needle 20 moves upward to the limit with respect to valve port portion 11
It sets;Closed position is that the opposite valve port portion 11 of needle 20 is moved downwardly to the fully closed position that extreme position is abutted with valve port portion 11
It sets.Driving mechanism includes coil 31 and rotor 32.Planetary gear reducing mechanism 40 includes output shaft 422, driving mechanism conduct
The input terminal of planetary gear reducing mechanism 40, planetary gear reducing mechanism 40 include sun gear 41, planet carrier 42, planetary gear 43 with
And it is fixed at the sleeve 44 on valve seat 10, sun gear 41, planet carrier 42 and sleeve 44 are coaxially disposed, and are set on planet carrier 42
It is equipped with the first installation axle 421, planetary gear 43 is set in the first installation axle 421, and sun gear 41 turns under the driving of driving mechanism
Dynamic, sun gear 41 drives planetary gear 43 to carry out rotation along 43 own axes of planetary gear, is provided with internal gear on the inner wall of sleeve 44
441, planetary gear 43 engaged with internal gear 441 so that multiple planetary gears 43 along sleeve 44 axis revolution with drive planet carrier 42 around
Own axes rotation, output shaft 422 are formed on planet carrier 42.50 output shaft 422 of transmission mechanism is driven by transmission mechanism 50
Needle 20 moves along a straight line, so that needle 20 moves between an open position and a closed.
It applies the technical scheme of the present invention, electric expansion valve includes the planetary gear reducing mechanism being arranged on valve seat 10
40, planetary gear reducing mechanism 40 has output shaft 422, and output shaft 422 is transported by 50 valve needle 20 of transmission mechanism along straight line
It moves so that needle 20 moves between an open position and a closed.Due to using internal messing in planetary gear reducing mechanism 40
Gear takes full advantage of transmission space, therefore the bulk of entire deceleration mechanism is slowed down than the spur gear under the same terms
Small more of mechanism (fixed shaft gear train).In addition, as shown in figure 13, since the reduction ratio calculation formula of planetary gear reducing mechanism isWherein a is sun gear, and b is fixed gear, and c is planetary gear, and H is planet carrier, therefore, in the item of identical size
Under part, more, the raising of reduction ratio bigger than the reduction ratio of spur-gear speed reducer structure of the reduction ratio of planetary gear reducing mechanism 40
So that the stroke control precision of needle 20 is higher.Therefore above structure enables electric expansion valve to reach high-precision, miniaturization
Requirement, solve electric expansion valve in the prior art be unable to reach when increasing flow-control scope high-precision, miniaturization
Requirement the problem of.
It should be noted that transmission mechanism 50 can convert the rotary motion of output shaft 422 to the axial fortune of needle 20
It is dynamic.
In the present embodiment, planetary gear reducing mechanism 40 is specially NGW type planetary gear reducing mechanism, NGW planet tooth
Wheel has that small in size, light-weight, power bracket is big for transmitting, high-efficient and stable working, axial dimension are small compared with fixed shaft gear train
The features such as, so that electric expansion valve when increasing flow-control scope, can reach the requirement of high-precision, miniaturization.
It should also be noted that, it will be appreciated by those skilled in the art that NGW type planetary gear reducing mechanism is common subtracts
Fast mechanism, the N in NGW type planetary gear reducing mechanism indicate that internal messing, W indicate external toothing, and G indicates common gear.
As shown in Fig. 4, Fig. 7 to Figure 12, in the present embodiment, planetary gear reducing mechanism 40 includes sun gear 41, planet
Frame 42, planetary gear 43 and the sleeve 44 being fixed on valve seat 10, sun gear 41, planet carrier 42 and sleeve 44 are coaxially set
It sets, planet carrier 42 includes at least one spaced first installation axle 421 in circumferential direction, and planetary gear 43 is set in the first peace
It fills on axis 421, when the driving sun gear 41 of driving mechanism rotates, sun gear 41 drives planetary gear 43 along itself axis of planetary gear 43
Line carries out rotation.Internal gear 441 is provided on the inner wall of sleeve 44, planetary gear 43 is engaged with internal gear 441 so that planetary gear 43
Axis along sleeve 44 revolves, final that planet carrier 42 is driven to carry out rotation around the own axes of planet carrier 42.Due to output shaft 422
Be formed on planet carrier 42, thus output shaft 422 can along the axis rotation of output shaft 422, output shaft 422 again with driver
Structure 50 cooperates, to realize that needle 20 moves between an open position and a closed.
First installation axle 421 can be one, and when the first installation axle 421 is one, planetary gear 43 is and the first installation
421 corresponding one, axis, the first installation axle 421 is located at the outer circumferential of the axis of planet carrier 42.
Preferably, the first installation axle 421 be in the circumferential direction of planet carrier 42 it is spaced it is multiple (it is more than two,
Such as 2,3,4 ...), planetary gear 43 be arranged in a one-to-one correspondence with the first installation axle 421 it is multiple (it is more than two, such as
2,3,4 ...).Above structure is simple, stable transmission.Above structure makes the operation of planetary gear reducing mechanism more
Stablize.Preferably, in the present embodiment, the first installation axle 421 is three, and planetary gear 43 is a pair of with the first installation axle 421 1
Three for should being arranged.
As shown in Figure 7 to 10, each planetary gear 43 is set in correspondingly in each first installation axle 421, when work, respectively
43 high speed rotation of planetary gear, planetary gear 43 is deviate from from the first installation axle 421 in order to prevent, as shown in Figure 1, in the present embodiment
In, planet carrier 42 further include at least two second installation axles 423 and be arranged in a one-to-one correspondence with the second installation axle 423 at least two
A muscle position 424, each muscle position 424 are wrapped in the outer circumferential of each second installation axle 423, the first installation axle 421 and the second installation axle
423 interval settings, planetary gear reducing mechanism 40 further includes cover board 45, and cover board 45 is provided with and the first installation axle 421 and second
The mounting hole 451 that installation axle 423 cooperates, the bottom surface of cover board 45 is abutted with the top surface of muscle position 424.In said structure, planetary gear
43 lower end can prevent planetary gear 43 from first by 45 backstop of cover board by 42 backstop of planet carrier, the upper end of planetary gear 43
Deviate from installation axle 421.Preferably, in the present embodiment, planet carrier 42 further includes bottom plate 425, bottom plate 425, the first installation axle
421, the second installation axle 423 and muscle position 424 together form planet carrier 42.Wherein, the first installation axle 421 and the second installation axle
423 are arranged at intervals on the top surface of bottom plate 425, and cover plate lid is located on the top surface of multiple muscle positions 424.
As shown in Fig. 3, Fig. 4 and Fig. 7, in the present embodiment, driving mechanism includes coil 31 and rotor 32, sun gear 41
It is arranged on rotor 32.Specifically, when coil 31 is powered, it will generate magnetic field, rotor 32 starts height under the influence of a magnetic field
Speed rotation.Since sun gear 41 is arranged on rotor 32, sun gear 41 can be rotated with it, and final realize drives multiple planets
Wheel 43 carries out the purpose of rotation along the own axes of planetary gear 43.Above structure is simple, it is easy to accomplish.Certainly, art technology
Personnel should be known that can also be rotated by motor direct-drive sun gear, such as motor output shaft is arranged in sun gear
End is to drive sun gear to rotate.
As shown in Fig. 4, Fig. 7 and Figure 11, in the present embodiment, rotor 32 has roof 321 and side wall 322, roof 321
First receiving space 1 is surrounded with side wall 322, sun gear 41 is arranged on the inside of roof 321 and extends downwardly, and at least partly goes
Star gear reduction 40 is contained in first receiving space 1.Above structure takes full advantage of the space in rotor 32, makes at least
Partial planetary gear reducing mechanism 40 is contained in the first receiving space 1 of rotor 32, therefore it is swollen to effectively reduce electronics
The volume of swollen valve realizes the purpose of miniaturization.
Preferably, in the present embodiment, sun gear 41 is integrally formed on the inside of roof 321, and above structure is simple, subtracts
Lack installation step, improves production efficiency.
As shown in figure 4, in the present embodiment, electric expansion valve further include: shell 60 is located at the top of valve seat 10, outside
There is the second accommodation space 2, planetary gear reducing mechanism 40 and transmission mechanism 50 are arranged in the second accommodation space 2 inside shell 60
It is interior.Above structure can either anti-locking system intermediary matter (refrigerant) loss can prevent again steam, dust and other impurities enter more
In accurate planetary gear reducing mechanism 40 and transmission mechanism 50, to improve planetary gear reducing mechanism 40 and transmission mechanism
50 service life.
Preferably, in the present embodiment, shell 60 is connected on valve seat 10 by connector.Certainly, those skilled in the art
Member is it should be known that shell 60 can also directly be connect with valve seat 10.Compared with being directly connected to, valve seat 10 is connected to by connector
On can effectively reduce the volume of valve seat 10, to further realize the purpose of miniaturization.
As shown in figure 4, in the present embodiment, upper frame structure 70, planetary gear reducing mechanism are fixedly installed in shell 60
40 further include mandrel 46, and mandrel 46 is threaded through from top to bottom in upper frame structure 70, sun gear 41 and planet carrier 42, wherein mandrel
The axis collinear of the axis and output shaft 422 of 46 axis and the axis of sun gear 41 and planet carrier 42.Above structure can
Guarantee the axis of sun gear 41 and the axis collinear of planet carrier 42, so that planetary gear reducing mechanism 40 runs well,
Avoid bite phenomenon occur between gear.
In order to further increase reduction ratio, as shown in Fig. 4, Fig. 7 to Figure 12, in the present embodiment, electric expansion valve includes
Multi-level planet gear speed reducer structure 40, output shaft 422 on the planetary gear 43 of afterbody planetary gear reducing mechanism 40 and passes
Motivation structure 50 cooperates, the output shaft 422 of upper level planetary gear reducing mechanism 40 in adjacent two-stage planet deceleration mechanism 40
Outer wall on be provided with external gear 4221, with external gear 4221 output shaft 422 formed next stage planetary gear reducing mechanism
Multiple planetary gears 43 of 40 sun gear 41, external gear 4221 and next stage planetary gear reducing mechanism 40 cooperate, so that next
Multiple planetary gears 43 of grade planetary gear reducing mechanism 40 are along its axis rotation.
Specifically, it is illustrated by taking two-stage planet deceleration mechanism 40 as an example, coil 31 is powered first, drives rotor 32
It rotates, the sun gear 41 on rotor 32 rotates with it.Sun gear 41 drives multiple planetary gears 43 of the first order along its axis rotation.
Multiple planetary gears 43 of the first order engaged with internal gear 441 so that the first order multiple planetary gears 43 along the first order sleeve 44
Axis revolution, the revolution of multiple planetary gears 43 of the first order so that the planet carrier 42 of the first order around its axis rotation so that
The output shaft 422 of the first order can be along its axis rotation.External gear 4221 is provided on the outer wall of the output shaft 422 of the first order.
The output shaft 422 of the first order with the external gear is equivalent to the sun gear 41 of the second level, the 422 rotation band of output shaft of the first order
Multiple planetary gears 43 of the dynamic second level are along its axis rotation.Multiple planetary gears 43 of the second level are engaged with internal gear 441 so that
Multiple planetary gears 43 of second level revolve along the axis of the sleeve 44 of the second level.The revolution of multiple planetary gears 43 of the second level is so that
The planet carrier 42 of second level finally enables the output shaft 422 of the second level along its axis rotation around its axis rotation.The second level
Output shaft 422 cooperates with transmission mechanism 50 again, to realize that needle 20 moves between an open position and a closed.
As shown in fig. 7, in the present embodiment, multi-level planet gear speed reducer structure 40 shares same sleeve 44.Above structure
Simply, reduce installation step, reduce production cost.Certainly, it will be appreciated by those skilled in the art that multi-stage planetary gear subtracts
The sleeve 44 of fast mechanism 40 can also be with split settings, as long as without relative rotation between sleeve 44 at different levels after guaranteeing installation.
As shown in fig. 7, in the present embodiment, multi-level planet gear speed reducer structure 40 shares same mandrel 46.Certainly, ability
Field technique personnel should be known that the mandrel 46 of multi-level planet gear speed reducer structure 40 can also be with split settings, as long as mandrel at different levels
It is coaxial between 46.
As shown in Fig. 5, Fig. 7, Fig. 8 and Figure 10, in the present embodiment, it is provided with mating groove 4222 on output shaft 422, is driven
Mechanism 50 includes screw rod 51 and the nut 52 being fixed on valve seat 10, and screw rod 51 includes cooperation section 511 and linkage section
512, at least partly cooperation section 511 is movably disposed in mating groove 4222.When output shaft 422 rotates, mating groove 4222
Cell wall and cooperation section 511 cooperates so that screw rod 51 rotates, be provided with external screw thread on the outer wall of linkage section 512, linkage section 512 with
Nut 52 is threadedly coupled, and the rotational motion of screw rod 51 is converted to linear motion.At this point, the cooperation section 511 of screw rod 51 is gradually
Far from mating groove 4222, needle 20 moves between an open position and a closed under the action of screw rod 51.
As shown in Figure 4 and Figure 6, in the present embodiment, electric expansion valve further include: valve needle cover 80 is set in outside needle 20
Side is simultaneously fixed on valve seat 10, and needle 20 is movably disposed in valve needle cover 80, valve needle cover 80 include construction section 81 with
And the guide section 82 positioned at 81 lower section of construction section, the junction formation step surface 83 of construction section 81 and guide section 82, guide section 82
It is adapted to needle 20;Spring 90 is located in construction section 81, and the abutting protrusion 21 at 20 top of one end and needle of spring 90 abuts,
The other end of spring 90 is abutted with step surface 83.Spring 90 is in compressive state always in construction section 81.When needle 20 is by closing
When closed position is mobile to open position, upward elastic-restoring force of the bottom surface of protrusion 21 by spring 90 is abutted, so that needle
20 are gradually distance from valve port portion 11.Specifically, when needing needle 20 to open valve port portion 11, screw rod is rotated and is moved upwards, needle
The power of supporting at 20 tops reduces therewith.When the downward power that screw rod 51 applies to needle 20 is less than the upward bullet that needle 20 is subject to
Property restoring force when, needle 20 then starts with the trend that moves upwards, and the stroke size that specific needle 20 moves up also is wanted
It is determined by the stroke that screw rod moves.Above structure is simple, and construction section 81 realizes the installation of spring 90, and guide section 82 realizes pair
The guiding of needle 20.
As shown in figure 4, in the present embodiment, there is cavity 6 in valve seat 10, be provided with annular flange in the cavity wall of cavity 6
12, the installation cavity 4 and the overcurrent chamber 5 below installation cavity 4 that cavity 6 is divided into installation nut 52 by annular flange 12, valve
Oral area 11 is formed in the cavity wall of overcurrent chamber 5, and the top of valve needle cover 80 is provided with outwardly extending flange 811,811 sandwiched of flange
Between nut 52 and the upper surface of annular flange 12.Above structure is simple, and valve needle cover 80 is enabled to be securely seated between valve
On seat 10.In the present embodiment, first pipe 100 and second pipe 110 are provided on valve seat 10, first pipe 100 passes through valve
Oral area 11 is connected to overcurrent chamber 5, and second pipe is directly connected to overcurrent chamber 5.Refrigerant can enter overcurrent by first pipe 100
Chamber 5 is simultaneously flowed out from second pipe 110, overcurrent chamber 5 can also be entered by second pipe 110 and flowed out from first pipe 100.
As shown in figure 4, in the present embodiment, the lower part of the cavity wall of overcurrent chamber 5 is provided with the second collar flange, second is cyclic annular
The inner side edge of flange cooperates along valve port portion 11, the lower surface of the second collar flange and first pipe 100 is formed.
Present invention also provides a kind of refrigeration systems, include: electronics according to the refrigeration system (not shown) of the application
Expansion valve, electric expansion valve are above-mentioned electric expansion valve.Since above-mentioned electric expansion valve has high-precision, small in size etc. excellent
Point, therefore also had the above advantages with its refrigeration system.
The foregoing is only a preferred embodiment of the present invention, is not intended to restrict the invention, for the skill of this field
For art personnel, the invention may be variously modified and varied.All within the spirits and principles of the present invention, made any to repair
Change, equivalent replacement, improvement etc., should all be included in the protection scope of the present invention.