CN1815068A - Speed-reduction type electronic expansion valve - Google Patents
Speed-reduction type electronic expansion valve Download PDFInfo
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- CN1815068A CN1815068A CN 200510023886 CN200510023886A CN1815068A CN 1815068 A CN1815068 A CN 1815068A CN 200510023886 CN200510023886 CN 200510023886 CN 200510023886 A CN200510023886 A CN 200510023886A CN 1815068 A CN1815068 A CN 1815068A
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Abstract
Present invention relates to a electronic expansion valve suitable for frequency conversion air conditioner, commercial air conditioner, minitype central air conditioning, chilled food display case and constant temperature and humidity equipment etc, belonging to air conditioning and refrigerating technology field. It contains repeating motor, speed reducing gear, valve body, and shell. Said stepping motor drives underdriving gear set for transferring power, combined with corrugated pipe to make adjustments to valve needle lift range. The decelerating effect of Underdriving gear set increases output torque to obtain large enough output torque by using smaller electromagnetic force, to satisfy large caliber and novel refrigerant requirement.
Description
Technical field
The present invention relates to a kind of electric expansion valve, particularly a kind of speed-reduction type electronic expansion valve is applicable to equipment such as frequency converting air conditioner, business air conditioner, small central air conditioning, chilled food showcase and constant temperature and humidity, belongs to the air conditioner refrigerating technical field.
Technical background
At present, in refrigeration system, electric expansion valve is subjected to the favor of refrigeration industry as refrigeration throttling device of new generation, especially uses very wide in the field of small commercial air-conditioning and central air-conditioner.Novel refrigerant R407c and R410a will have replacement that atmospheric ozone layer is had the trend of the refrigeration agent R22 of destruction in addition, bring some new requirements to electric expansion valve.Electric expansion valve passes through to regulate the aperture of its valve opening, and then regulates the flow of cold (heat) system.In general, each terminal cold of central air-conditioner wants big with respect to the wall hanging detachable air conditioner, and the bore of used electric expansion valve requires also corresponding increase.Yet after the bore of electric expansion valve increased, the driving force of electric expansion valve was wanted corresponding increase.For the air-conditioning that adopts novel refrigerant R407c and R410a, system pressure equally also requires to increase the driving force of electric expansion valve than the height of original R22.Above-mentioned two kinds of driving forces that also can increase electric expansion valve by the gearing friction that reduces screw thread.
Existing electric expansion valve is divided into two kinds of direct-acting type electronics expansion valve and speed-reduction type electronic expansion valves.
The driving force that increases direct-acting type electronics expansion valve can be started with from two aspects: being the electric current that improves stator coil on the one hand, is the magnetic that increases rotor on the other hand.If improve the electric current of stator coil, then coil temperature rise is too high, can influence the life-span of coil and rotor, and the magnetizing field that rotor produced simultaneously can not increase because of the increase of stator current is unlimited; If increase the magnetic of rotor, then be subjected to the restriction of material behavior and magnetizing clamp electric current.
The driving force that increases speed-reduction type electronic expansion valve also has two kinds of methods, the one, the power of motor; The 2nd, the reduction speed ratio of increase train of reduction gears.
Reducing the screw thread gearing friction just needs to improve the thread surface processing method or select novel screw pair material for use, but this has increased the difficulty of processing of manufacturer again simultaneously and has improved cost.
Utility model patent 97243335.X, a kind of direct-acting type electronics expansion valve of domestic air conditioning is disclosed, this expansion valve is to utilize the valve rod rotation mutually direct-connected with stepping motor rotor, make the valve rod front end with needle move up and down, thereby the aperture of control valve bore since this structure in the direct-connected valve rod of stepper motor, make valve body structure compactness, volume little, but because the direct effect of stepper motor, the aperture that makes valve opening is stepping, is not continuous.And overall obturation effect is also undesirable.
Utility model patent 92234967.3 discloses the micro-processor controlled driving electric expansion valve of a kind of usefulness, and the needle that this electric expansion valve utilizes stepper motor engagement one-level reduction gear and then transmission to be positioned under the bellows moves up and down, thus the aperture of regulating valve opening.The structural volume of this kind electric expansion valve is still very big, and its technical performance to bellows has relatively high expectations, and with existing technical merit, is difficult to process.
Summary of the invention
The invention provides big, the suitable wide speed-reduction type electronic expansion valve of range of flow of a kind of driving force.Electric expansion valve of the present invention reaches the purpose of the moment of torsion that increases rotating shaft by increasing the reduction speed ratio of train of reduction gears.Make the present invention can be applicable to the air-conditioning system of novel cryogen R407c or R410a, and can be suitable for high-power compressor such as central air-conditioner and need.
For achieving the above object, inventive concept of the present invention is as follows: give stepper motor certain driving valve or close the valve pulse by driving power, the train of reduction gears of the gear shaft engagement of drive and stepper motor, train of reduction gears is rotated with thread spindle, drive moving up and down of thread spindle, thereby the needle that promotes the lower end moves up and down, thereby reaches the purpose of control valve port cold medium flux.This refrigeration system is regulated level and smooth stable, and flow curve and direct-acting type electronics expansion valve more more approach linearity.
The present invention adopts following technical proposals to be achieved: a kind of speed-reduction type electronic expansion valve, comprise stepper motor 1, reducing gear 2 and valve body 3, lead 11 on the described stepper motor 1 connects with wire connector 12, be provided with needle 31 and bellows 32 in the described valve body 3, the upper end of needle 31 is enclosed within the bellows 32; It is characterized in that: described reducing gear 2 is installed on the housing 4, is fixed with stepper motor 1 on housing 4; Described reducing gear 2 is made of train of reduction gears 21 and thread spindle 22, and the end tooth wheel of train of reduction gears 21 meshes with the gear shaft 13 of stepper motor 1, the other end gear and thread spindle 22 engagements; Described housing 4 is connected with valve body 3 by valve body joint 5, is provided with axis hole 51 in the middle of the described valve body joint 5, and the upper end of described thread spindle 22 is rotatable fixing by axle bed 41, and its lower end passes the axis hole 51 of valve body joint 5 and the top of the needle 31 in the valve body 3 holds.
Described axis hole 51 is provided with and thread spindle 22 respective threads, and thread spindle 22 is fixed on the valve body joint 5 by the screw thread on it, and the upper end of valve body joint 5 is fixed on the bottom of housing 4.
The top of described valve body 3 is provided with outside thread, and is fixing by nut and valve body joint 5.
The upper end of described thread spindle 22 is equipped with bearing 23, and the surface of contact of described bearing 23 and thread spindle 22 is step-like.
Described train of reduction gears 21 is made of three grades of reduction gear, and the scope of reduction speed ratio was at 20: 1～40: 1.
The lower end of described thread spindle 22 is provided with spherical ball 24.
Described thread spindle 22 adopts stainless steel or the aluminum bronze that has high hardness, highi degree of accuracy, high wear resistance and self lubricity is arranged.
Described needle 31 is for dividing body structure, and upper and lower two-part are fixing by bonding.
Leave the gap between the inner chamber 33 of the bottom of described needle 31 and valve body 3.
Be provided with corrugated header 34 in the upper end of bellows 32.
Described bellows 32 material selection beryllium bronzes, sidewall is even protruding structure, in the tensile elongation of bellows 32, the elasticity coefficient scope of bellows is 7.5～10N/mm, effective wave number 8～12 ripples, bellows thickness is 0.1～0.15mm.
Lead 11 on the described stepper motor 1 is enveloping type joint forms of double row's pin with the Placement of wire connector 12.
The scheme that increases the electric expansion valve driving force among the present invention is recently to realize by the deceleration that increases train of reduction gears.It drives the train of reduction gears transferring power by dc stepper motor, with bellows valve needle lift is regulated.The decelerating effect of train of reduction gears has increased the output torque greatly, makes less electromagnetic force obtain enough big output torque, can satisfy the requirement of heavy caliber and novel refrigerant.That electric expansion valve of the present invention has is energy-conservation, noise is little, action response is fast, the cold medium flux regulation range is wide, reliability and the high advantage of controllability, can obtain extensive use.
Because bellows 32 structures that the present invention adopts itself have elasticity and sealing function, can not only control the aperture between needle 31 and the valve port rapidly and accurately, can be because of the stuck valve port of the deviation of needle 31, phenomenon swings in the time of overcoming direct-acting type electronics expansion valve rotor rotation simultaneously.
Description of drawings
Fig. 1 is a structural representation of the present invention;
Fig. 2 is the structural representation of reducing gear of the present invention;
Fig. 3 is the structural representation of the bellows among Fig. 1 of the present invention;
Fig. 4 a is the single row needle construction schematic representation of stepper motor lead-in wire of the present invention with the lead wiring;
Fig. 4 b is the single row pin welding manner structural representation of stepper motor lead-in wire of the present invention with the lead wiring;
Fig. 5 a is the double row needle construction schematic representation of stepper motor lead-in wire of the present invention with the lead wiring;
Fig. 5 b is the double row pin welding manner structural representation of stepper motor lead-in wire of the present invention with the lead wiring.
Embodiment
Illustrated in figures 1 and 2, a kind of speed-reduction type electronic expansion valve comprises stepper motor 1, reducing gear 2 and valve body 3.The outside of described stepper motor 1 is covered with electrical machinery cover 14, and the lead 11 on the stepper motor 1 connects with wire connector 12, and wire harness assembly is inserted in the lower end of wire connector 12, and uses epoxy sealing.Acceptance is from the drive pulse signal of frequency conversion system microprocessor.Described reducing gear 2 is installed on the housing 4, is fixed with stepper motor 1 on housing 4.Described reducing gear 2 is made of train of reduction gears 21 and thread spindle 22, and the end tooth wheel of described train of reduction gears 21 meshes with the gear shaft 13 of stepper motor 1, the other end gear and thread spindle 22 engagements that gear is housed.Diapire at housing 4 has a hole, and valve body joint 5 is installed in this hole, and the upper end of valve body joint 5 is fixed on the housing 4.The top of described valve body 3 is provided with outside thread, fixes by the nut 6 and the lower end of valve body joint 5.Be provided with needle 31 and bellows 32 in the described valve body 3, the upper end of needle 31 is enclosed within the bellows 32, is provided with corrugated header 34 in the upper end of bellows 32.The centre of valve body joint 5 is provided with axis hole 51, on axis hole 51, be provided with and thread spindle 22 respective threads, thread spindle 22 is spun on the valve body joint 5 by the screw thread on it, the upper end of described thread spindle 22 is rotatable fixing by the axle bed on the housing 4 41, and the top of the needle 31 that the axis hole 51 that its lower end passes valve body joint 5 and valve body 3 are interior holds mutually.
The upper end of described thread spindle 22 is equipped with bearing 23, and the surface of contact of this bearing 23 and thread spindle 22 is step-like.Make the upper end of thread spindle 22 be in vacant state like this, can prevent thread spindle 22 in assembly process,, and then cause the screw thread dieback, the thread pitch when having reduced power screw, make the screw thread pressurized and produce wear phenomenon because of the concentricity problem produces crookedly.
Wherein train of reduction gears 21 is three grades of reduction gear.Under the prerequisite that satisfies intensity and moment output requirement, the scope of reduction speed ratio is 20: 1～40: 1.For example reduction speed ratio is 20: 1 o'clock, and the modulus of three pairs of gear trains is 0.4, and the number of teeth is 12: 32,10: 25, and 10: 25.Reduction speed ratio is 40: 1 o'clock, and the modulus of three pairs of gear trains is 0.3, and the number of teeth is 10: 36,9: 30, and 9: 30.Reduction speed ratio is 30: 1 o'clock, and the modulus of three pairs of gear trains is respectively 0.3,0.3,0.4,0.4,0.4,0.4, and the number of teeth was respectively 13: 39,9: 30; 12: 36.When reduction speed ratio changed, each was to the centre distance respective change of gear.With respect to direct-acting type electronics expansion valve, the speed-reduction type electronic expansion valve structure is more compact, and the bore that is suitable for is bigger.
When the thread spindle 22 in the reducing gear 2 was done axially reciprocating, the needle stroke final error was in 5 μ m.In order to improve the transmission efficiency of thread spindle 22, double thread axle 22 adopts high hardness, highi degree of accuracy, high wear resistance and the material of self lubricity is arranged, can select stainless steel material for use, the aluminium bronze can improve the precision of screw pair like this as the screw pair material, makes the accuracy of thread of thread spindle reach 6g or more than the 6g.
Bellows can bear the bursting pressure more than the 12MPa after moulding and welding, then the bursting pressure requirement is higher to novel refrigerant, is 16.68MPa.Bellows of the present invention, as shown in Figure 3, in the length that bellows 32 stretches, the elasticity coefficient scope of bellows 32 is 7.5～10N/mm, the life-span of bellows is more than 100,000 times, effective wave number 8～12 ripples, bellows thickness is 0.1～0.15mm.
Needle 31 is for dividing body structure, and upper and lower two-part are fixing by bonding.Needle 31 adopts this kind structures, and is not only easy to process, and its upper and lower two-part can adopt unlike material, can save cost.
Because the spring function that bellows 32 has when needle 31 moves downward close port, leaves the gap between the inner chamber 33 of the bottom of needle 31 and valve body 3.Can guarantee the buffering and the self-aligning of needle 31, thereby improve the working life of needle 31 and reduced internal leakage when closing.In addition, when electric expansion valve closes valve, rotate, compress needle 31, then by the elasticity of bellows 32 itself, needle 31 is pulled, so bellows 32 has the function that needle 31 is resetted when driving valve by thread spindle 22.
In addition, bellows 32 has seal action again, because the volume of housing 4 is relatively large, if there is high-pressure refrigerant to enter, can cause stepper motor cover and housing riveted joint place to break, and cause freezing medium leakage, simultaneously also can be to the material production adverse effect of reduction gear, motor coil and rotor, so need refrigeration agent to be sealed in the valve body 3 with bellows 32.
When give stepper motor 1 certain drive valve or close the valve pulse time, the gear shaft 13 of stepper motor 1 drives the train of reduction gears 21 with its engagement, this train of reduction gears 21 is rotated with thread spindle 22, promote needle 31 by the spherical ball on the thread spindle 22 and move up and down, thus the size of control valve port opening.
Fig. 4 a and Fig. 4 b, Fig. 5 a and Fig. 5 b are the Type of Welding of stepper motor lead-in wire and lead fitting.Wherein Fig. 4 a and Fig. 4 b are that single row's pin and stepper motor lead bonding adopt direct joint form, and this mode is for some contact welding, and is relatively simple for structure, can directly purchase standard piece and use.Fig. 5 a and Fig. 5 b are that double row's pin and stepper motor lead bonding adopt enveloping type; This structure can effectively prevent to produce rosin joint and the generation that is connected unreliable these two problems in course of working, and because the direct overlapping mode of spacing wants big, is convenient to workman's operation.
Speed-reduction type electronic expansion valve of the present invention adopts claw polar type step motor.By selecting for use neodymium-iron-boron magnetic material to make rotor, optimize the slenderness ratio of rotor, and optimize the methods such as line footpath, the number of turn of coil, make stepper motor satisfy under the prerequisite of output torque request, power has only about 2W, and also increase greatly of reliability.The stepper motor of speed-reduction type electronic expansion valve adopts 12 pairs of pawl utmost points, and driving mode is 4 phases, 4 bat formulas, and it is 2000/48/30 ≈ 1.39 that whole process moves radially the number of turns, and promptly the omnidistance moving displacement of needle 31 is about 0.7mm.
During use, give driving valve or closing the valve pulse of 2000 of stepper motors by driving power, the train of reduction gears 21 of the gear shaft engagement of drive and stepper motor 1, train of reduction gears 21 is rotated with thread spindle 22, reduction speed ratio is 30: 1,48 pulse/commentaries on classics of motor, the outside thread that passes through thread spindle 22 and the thread engagement of valve body joint 5 promote lower end needle 31 and move up and down, thereby reach the purpose of control valve port cold medium flux.The pitch of thread spindle 22 is 0.5mm, and the omnidistance moving displacement of needle 31 is about 0.7mm.This refrigeration system is regulated level and smooth stable, and flow curve and direct-acting type electronics expansion valve more more approach linearity.
Adopt electric expansion valve of the present invention, its transmission efficiency height, action response are fast, the cold medium flux regulation range is wide, driving moment and the loading moment fluctuation is little, output torque speed-reduction type electronic expansion valve greatly and flexibly in the rotor turning course, can be adapted to the air-conditioning system of novel refrigerant R407c or R410a.
Claims (14)
1. speed-reduction type electronic expansion valve, comprise stepper motor (1), reducing gear (2) and valve body (3), lead (11) on the described stepper motor (1) connects with wire connector (12), be provided with needle (31) and bellows (32) in the described valve body (3), the upper end of needle (31) is enclosed within the bellows (32); It is characterized in that: described reducing gear (2) is installed on the housing (4), is fixed with stepper motor (1) on housing (4); Described reducing gear (2) is made of train of reduction gears (21) and thread spindle (22), the end tooth wheel of train of reduction gears (21) and gear shaft (13) engagement of stepper motor (1), the other end gear and thread spindle (22) engagement; Described housing (4) is connected with valve body (3) by valve body joint (5), be provided with axis hole (51) in the middle of the described valve body joint (5), the upper end of described thread spindle (22) is rotatable fixing by axle bed (41), and the top of the needle (31) that the axis hole (51) that its lower end passes valve body joint (5) and valve body (3) are interior holds mutually.
2. a kind of speed-reduction type electronic expansion valve according to claim 1, it is characterized in that: described axis hole (51) is provided with and thread spindle (22) respective threads, thread spindle (22) is fixed on the valve body joint (5) by the screw thread on it, and the upper end of valve body joint (5) is fixed on the bottom of housing (4).
3. a kind of speed-reduction type electronic expansion valve according to claim 1 and 2 is characterized in that: the top of described valve body (3) is provided with outside thread, and is fixing by nut and valve body joint (5).
4. a kind of speed-reduction type electronic expansion valve according to claim 1 and 2 is characterized in that: the upper end of described thread spindle (22) is equipped with bearing (23), and the surface of contact of described bearing (23) and thread spindle (22) is step-like.
5. a kind of speed-reduction type electronic expansion valve according to claim 1 and 2 is characterized in that: described train of reduction gears (21) is made of three grades of reduction gear, and the scope of reduction speed ratio was at 20: 1～40: 1.
6. a kind of speed-reduction type electronic expansion valve according to claim 3 is characterized in that: described train of reduction gears (21) is made up of three groups of reduction gear, and the scope of reduction speed ratio was at 20: 1～40: 1.
7. a kind of speed-reduction type electronic expansion valve according to claim 1 and 2 is characterized in that: the lower end of described thread spindle (22) is the structure of spherical ball.
8. a kind of speed-reduction type electronic expansion valve according to claim 3 is characterized in that: the lower end of described thread spindle (22) is the structure of spherical ball.
9. a kind of speed-reduction type electronic expansion valve according to claim 1 and 2 is characterized in that: described thread spindle (22) adopts stainless steel or the aluminum bronze that has high hardness, highi degree of accuracy, high wear resistance and self lubricity is arranged.
10. a kind of speed-reduction type electronic expansion valve according to claim 1 and 2 is characterized in that: described needle (31) is for dividing body structure, and upper and lower two-part are fixing by bonding.
11. a kind of speed-reduction type electronic expansion valve according to claim 1 and 2 is characterized in that: leave the gap between the inner chamber (33) of the bottom of described needle (31) and valve body (3).
12. a kind of speed-reduction type electronic expansion valve according to claim 1 and 2 is characterized in that: be provided with corrugated header (34) in the upper end of bellows (32).
13. a kind of speed-reduction type electronic expansion valve according to claim 1 and 2, it is characterized in that: described bellows (32) material selection beryllium bronze, sidewall is even protruding structure, in the tensile elongation of bellows (32), the elasticity coefficient scope of bellows is 7.5～10N/mm, effective wave number 8～12 ripples, bellows thickness is 0.1～0.15mm.
14. a kind of speed-reduction type electronic expansion valve according to claim 1 and 2 is characterized in that: the lead (11) on the described stepper motor (1) is the enveloping type joint form of double row's pin with the Placement of wire connector (12).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510023886 CN1815068A (en) | 2005-02-06 | 2005-02-06 | Speed-reduction type electronic expansion valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510023886 CN1815068A (en) | 2005-02-06 | 2005-02-06 | Speed-reduction type electronic expansion valve |
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| CN1815068A true CN1815068A (en) | 2006-08-09 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN 200510023886 Pending CN1815068A (en) | 2005-02-06 | 2005-02-06 | Speed-reduction type electronic expansion valve |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101761708B (en) * | 2008-11-06 | 2011-10-12 | 浙江三花股份有限公司 | Corrugated pipe and electronic expansion valve using the same |
| CN101761709B (en) * | 2008-11-06 | 2012-07-25 | 浙江三花股份有限公司 | Corrugated pipe and electronic expansion valve using the same |
| CN103453201A (en) * | 2012-06-04 | 2013-12-18 | 浙江三花股份有限公司 | Electronic expansion valve and assembling method |
| CN103673426A (en) * | 2012-09-10 | 2014-03-26 | 青岛海信日立空调系统有限公司 | Opening feedback electronic expansion valve and control system thereof |
| CN108061191A (en) * | 2017-11-22 | 2018-05-22 | 北京动力机械研究所 | A kind of valve motor drive mechanism |
| WO2018177284A1 (en) * | 2017-03-28 | 2018-10-04 | 浙江三花智能控制股份有限公司 | Electronic expansion valve and refrigeration system having same |
| CN110375103A (en) * | 2018-04-13 | 2019-10-25 | 浙江三花智能控制股份有限公司 | Motor-driven valve |
-
2005
- 2005-02-06 CN CN 200510023886 patent/CN1815068A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101761708B (en) * | 2008-11-06 | 2011-10-12 | 浙江三花股份有限公司 | Corrugated pipe and electronic expansion valve using the same |
| CN101761709B (en) * | 2008-11-06 | 2012-07-25 | 浙江三花股份有限公司 | Corrugated pipe and electronic expansion valve using the same |
| CN103453201A (en) * | 2012-06-04 | 2013-12-18 | 浙江三花股份有限公司 | Electronic expansion valve and assembling method |
| CN103673426A (en) * | 2012-09-10 | 2014-03-26 | 青岛海信日立空调系统有限公司 | Opening feedback electronic expansion valve and control system thereof |
| CN103673426B (en) * | 2012-09-10 | 2016-11-23 | 青岛海信日立空调系统有限公司 | A kind of open degree feedback electric expansion valve and control system thereof |
| WO2018177284A1 (en) * | 2017-03-28 | 2018-10-04 | 浙江三花智能控制股份有限公司 | Electronic expansion valve and refrigeration system having same |
| CN108061191A (en) * | 2017-11-22 | 2018-05-22 | 北京动力机械研究所 | A kind of valve motor drive mechanism |
| CN108061191B (en) * | 2017-11-22 | 2019-05-10 | 北京动力机械研究所 | A kind of valve motor drive mechanism |
| CN110375103A (en) * | 2018-04-13 | 2019-10-25 | 浙江三花智能控制股份有限公司 | Motor-driven valve |
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