CN114320921A - Double-end claw type pump rotor molded lines - Google Patents
Double-end claw type pump rotor molded lines Download PDFInfo
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- CN114320921A CN114320921A CN202111656647.6A CN202111656647A CN114320921A CN 114320921 A CN114320921 A CN 114320921A CN 202111656647 A CN202111656647 A CN 202111656647A CN 114320921 A CN114320921 A CN 114320921A
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Abstract
The invention relates to a double-head claw type pump rotor profile, which comprises a rotor 1 and a rotor 2, wherein the rotor 1 and the rotor 2 respectively rotate around a rotor shaft rotation center O of the rotor 1 and the rotor 21And the rotor shaft rotation center O2Symmetry; the upper half rotor profile of the rotor 1 is cycloidal a by point meshing1b1Tip to tip rolling arc b1c1C, transition arc1d1Transition arc d1e1Arc e of contact with tooth bottom1f1The upper half part of the rotor profile of the rotor 2 is formed by point meshing cycloid a2b2Round arc b with pairs of tooth bottoms2c2Arc envelope c2d2Arc envelope d2e2And the tooth crest pair rolling arc e2f2Forming; a of the rotors 1 and 21b1And a2Mesh, b1And a2b2Mesh, b1c1And b2c2Mesh, c1d1And c2d2Mesh, d1e1And d2e2Mesh, e1f1And e2f2And (4) meshing. The claw type pump rotor profile ensures that claw type pump rotors are correctly meshed when rotating in a synchronous and opposite direction, solves the problems of complex structure and low volume utilization coefficient of the existing claw type pump rotors, and improves the working performance of the claw type pump.
Description
Technical Field
The invention relates to the technical field of mechanical engineering, in particular to a double-end claw type pump rotor profile.
Background
The claw type pump as a rotary vacuum compressor has the advantages of compact structure, reliable operation, long mechanical life, low vibration noise, dry oil-free compression and the like, is widely applied to various fields of food, medicine, chemical industry and the like, and has good application prospect in low-pressure gas conveying. In particular, the fuel cell has attracted attention because of its oil-free compression characteristic, which is well-behaved in the hydrogen return system of the fuel cell, and thus has a great potential in the field of future hydrogen energy application.
The claw type pump consists of a pair of intermeshing rotors and an 8-shaped compression cavity, and the rotors synchronously rotate in different directions to drive the volume of gas in the compression cavity to periodically change so as to realize the processes of gas suction, compression and exhaust. Therefore, the claw rotor is used as a core component of the claw pump, and the compression performance of the claw pump, such as air tightness, volume utilization rate, working efficiency and service life, is directly affected by the shape design of the claw rotor. The meshed double-head rotor molded lines are composed of multiple sections of curves, each section of curve is correspondingly meshed in the synchronous and opposite-direction rotating process, and the molded line of each rotor is divided into an upper part and a lower part which are symmetrical about a rotating center. However, the existing double-end claw type rotor profile has the defects of complex structure composition, high processing difficulty, high cost, low volume utilization rate and the like.
Disclosure of Invention
To the not enough of above-mentioned prior art, this patent application will provide a double-end claw formula pump rotor molded lines to guarantee that claw formula pump rotor is correctly meshed when synchronous incorgruous rotation, and solve the problem that the structure composition of the claw formula pump rotor that exists is complicated among the prior art, the volume coefficient of utilization is low, thereby greatly improve claw formula pump working property.
In order to solve the technical problems, the invention adopts the following technical scheme:
a double-head claw type pump rotor profile comprises a rotor 1 and a rotor 2, wherein the rotor 1 and the rotor 2 are respectively arranged around a rotor shaft rotation center O of the rotor 1 and the rotor 21And the rotor shaft rotation center O2Symmetry;
the upper half part of the rotor profile of the rotor 1 is in point meshing cycloid a1b1Tip to tip rolling arc b1c1C, transition arc1d1Transition arc d1e1Arc e of contact with tooth bottom1f1The upper half part of the rotor profile of the rotor 2 is formed by point meshing cycloid a2b2Round arc b with pairs of tooth bottoms2c2Arc envelope c2d2Arc envelope d2e2And the tooth crest pair rolling arc e2f2Forming;
the rotors 1 and 2 each rotate around the rotor axis rotation center O1And the rotor shaft rotation center O2During synchronous rotation in different directions, points are meshed with cycloids a1b1And point a2Mesh, point b1Cycloidal a engaged with point2b2Meshing, tooth tip to rolling arc b1c1Arc b of contact with tooth bottom2c2Engaging, transition arc c1d1And the arc envelope c2d2Engaging, transition arc d1e1And the arc envelope d2e2Meshing, bottom of tooth pair rolling arc e1f1Arc e of contact with tooth crest2f2Meshing;
the point b1Point a2Is a sharp point, point a1Point c1Point d1Point e1Point f1Point b2Point c2Point d2Point e2Point f2Are both two adjacent sectionsThe common tangent point of the curve forms a smooth curve, so that the meshing process is stable;
the pitch circle radius of the rotor 1 is r1The pitch circle radius of the rotor 2 is r2The rotor 1 and the rotor 2 are synchronously meshed, and the meshing parameter transmission ratio i is r1/r2The pitch radii of rotor 1 and rotor 2 are equal, i.e. r, to 11＝r2And the center distance A is r1+r2＝2r1。
Further, point-meshing cycloids a1b1Satisfies the following formula:
xab1＝acostab-bcosctab
yab1＝-(asintab-bsinctab)
point meshing cycloid a2b2Satisfies the following formula:
xab2＝acostab-bcosctab
yab2＝asintab-bsinctab
wherein a is the distance from the center of the rolling circle to the center of the base circle, a is A, and the swing diameter b is Rh，A、RhIs known wherein RhThe radius of the addendum circle is,
c＝a/r1＝2。
further, the addendum is opposite to the rolling arc b1c1Satisfies the following formula:
xbc1＝rbccostbc
ybc1＝rbcsintbc
round arc b of gear bottom pair rolling2c2Satisfies the following formula:
xbc2＝(A-rbc)costbc
ybc2＝(A-rbc)sintbc
wherein r isbcIs b is1c1Radius of arc of (d), rbc＝Rh；tbc∈(0,α1)，α1Is b is1c1Arc of (a)1Are known.
Further, a transition arc c1d1Satisfies the following formula:
xcd1＝(rbc-rcd)cosα1+rcdcostcd
ycd1＝(rbc-rcd)sinα1+rcdsintcd
circular arc envelope c2d2Satisfies the following formula:
wherein r iscdIs c1d1The radius of the arc of (a) is,
tcd∈(α1,α1+α2)，α2is c1d1Arc of (a)2Are known.
Further, a transition arc d1e1Satisfies the following formula:
circular arc envelope d2e2Satisfies the following formula:
wherein r isdeIs d1e1The radius of the arc of (a) is,
tde∈(α1+α2,π-α4)。
further, the pair of tooth bottoms is rounded by an arc e1f1Satisfies the following formula:
xef1＝refcostef
yef1＝refsintef
tip to tip arc e2f2Satisfies the following formula:
xef2＝(A-ref)costef
yef2＝(A-ref)sintef
wherein r isefIs e1f1Radius of arc of (d), ref＝A-rbc；tef∈(π-α4,π)，α4Is e1f1Arc of (a)4Are known.
In summary, the rotor profile of the double-head claw pump provided by the invention is only composed of cycloid, arc and corresponding meshing curve, and can realize the correct meshing and stable operation of the rotor pair, so as to ensure gas compression and reduce internal leakage. Compared with the existing claw type pump rotor, the air tightness and the volume utilization coefficient of the pump are improved, the pumping speed of the claw type pump is further improved, and the claw type pump rotor has stronger practicability; meanwhile, the method has important significance for enriching the types of the rotor profiles of the claw type pump and promoting the development of the claw type pump.
Drawings
Fig. 1 is a schematic structural diagram of a rotor profile of a double-headed claw pump according to the present invention.
Fig. 2 is a drawing of the suction stage of the claw pump in fig. 1, in which the air cavity between the rotors is communicated with the suction port to realize the suction process of the compression cavity.
Fig. 3 is a transportation stage diagram of the claw pump in fig. 1, at this time, the air cavity between the rotors is not communicated with the air suction port and the air exhaust port, the volume of the air is not changed, and the transportation process of the compression cavity is realized.
Fig. 4 is a compression stage diagram of the claw pump shown in fig. 1, in which the air chamber between the rotors is not communicated with the air suction port and the air discharge port, but the volume of the air chamber between the rotors is reduced, thereby realizing the compression process of the compression chamber.
Fig. 5 is a diagram of the exhaust stage of the claw pump of fig. 1, in which the air chamber between the rotors is communicated with the exhaust port to realize the exhaust process of the compression chamber.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings. In the description of the present invention, it is to be understood that the orientation or positional relationship indicated by the orientation words such as "upper, lower" and "top, bottom" etc. are usually based on the orientation or positional relationship shown in the drawings, and are only for convenience of description and simplicity of description, and in the case of not making a reverse description, these orientation words do not indicate and imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore, should not be interpreted as limiting the scope of the present invention; the terms "inner and outer" refer to the inner and outer relative to the profile of the respective component itself.
As shown in fig. 1-5, a double-ended claw pump rotor profile comprises a rotor 1 and a rotor 2, wherein the rotor 1 and the rotor 2 are respectively arranged around a rotor shaft rotation center O1And the rotor shaft rotation center O2Symmetry;
the upper half of the rotor 1Rotor profile cycloid a formed by point meshing1b1Tip to tip rolling arc b1c1C, transition arc1d1Transition arc d1e1Arc e of contact with tooth bottom1f1The upper half part of the rotor profile of the rotor 2 is formed by point meshing cycloid a2b2Round arc b with pairs of tooth bottoms2c2Arc envelope c2d2Arc envelope d2e2And the tooth crest pair rolling arc e2f2Forming;
the rotors 1 and 2 each rotate around the rotor axis rotation center O1And the rotor shaft rotation center O2During synchronous rotation in different directions, points are meshed with cycloids a1b1And point a2Mesh, point b1Cycloidal a engaged with point2b2Meshing, tooth tip to rolling arc b1c1Arc b of contact with tooth bottom2c2Engaging, transition arc c1d1And the arc envelope c2d2Engaging, transition arc d1e1And the arc envelope d2e2Meshing, bottom of tooth pair rolling arc e1f1Arc e of contact with tooth crest2f2Meshing;
the point b1Point a2Is a sharp point, point a1Point c1Point d1Point e1Point f1Point b2Point c2Point d2Point e2Point f2The common tangent points of two adjacent curves form smooth curves, so that the meshing process is stable;
the pitch circle radius of the rotor 1 is r1The pitch circle radius of the rotor 2 is r2The rotor 1 and the rotor 2 are synchronously meshed, and the meshing parameter transmission ratio i is r1/r2The pitch radii of rotor 1 and rotor 2 are equal, i.e. r, to 11＝r2And the center distance A is r1+r2＝2r1。
Further, point-meshing cycloids a1b1Satisfies the following formula:
xab1＝acostab-bcosctab
yab1＝-(asintab-bsinctab)
point meshing cycloid a2b2Satisfies the following formula:
xab2＝acostab-bcosctab
yab2＝asintab-bsinctab
wherein a is the distance from the center of the rolling circle to the center of the base circle, a is A, and the swing diameter b is Rh，A、RhIs known wherein RhThe radius of the addendum circle is,
c＝a/r1＝2。
further, the addendum is opposite to the rolling arc b1c1Satisfies the following formula:
xbc1＝rbccostbc
ybc1＝rbcsintbc
round arc b of gear bottom pair rolling2c2Satisfies the following formula:
xbc2＝(A-rbc)costbc
ybc2＝(A-rbc)sintbc
wherein r isbcIs b is1c1Radius of arc of (d), rbc＝Rh；tbc∈(0,α1)，α1Is b is1c1Arc of (a)1Are known.
Further, a transition arc c1d1Satisfies the following formula:
xcd1＝(rbc-rcd)cosα1+rcdcostcd
ycd1＝(rbc-rcd)sinα1+rcdsintcd
circular arc envelope c2d2Satisfies the following formula:
wherein r iscdIs c1d1The radius of the arc of (a) is,
tcd∈(α1,α1+α2)，α2is c1d1Arc of (a)2Are known.
Further, a transition arc d1e1Satisfies the following formula:
circular arc envelope d2e2Satisfies the following formula:
wherein r isdeIs d1e1The radius of the arc of (a) is,
tde∈(α1+α2,π-α4)。
further, the pair of tooth bottoms is rounded by an arc e1f1Satisfies the following formula:
xef1＝refcostef
yef1＝refsintef
tip to tip arc e2f2Satisfies the following formula:
xef2＝(A-ref)costef
yef2＝(A-ref)sintef
wherein r isefIs e1f1Radius of arc of (d), ref＝A-rbc；tef∈(π-α4,π)，α4Is e1f1Arc of (a)4Are known.
The verification of the meshing operation states of the rotor profiles of the claw type pump under different rotation angles in the graphs of fig. 2 to fig. 5 shows that the rotor profiles of the claw type pump are reasonable in design, the driving rotor 1 and the driven rotor 2 can be effectively guaranteed to be correctly meshed in the operation process, the gas inlet, the gas outlet and the gas compression process can be effectively realized by matching the upper gas inlet 4, the gas outlet 5 and the compression cavity 3, the high-pressure gas in the gas compression process is prevented from leaking into the low-pressure gas inlet end by the precise meshing of the rotors, and the gas tightness of the compression cavity is improved. And because the volume of the compression cavity occupied by the rotor is smaller, the higher volume utilization coefficient is ensured, and the performance of the claw pump is improved.
The black shaded portions in fig. 2 to 5 indicate inter-rotor air chambers.
Fig. 2 is a view of the claw type air suction stage, in which the air cavity between the rotors is communicated with the air suction port to realize the air suction process of the compression cavity.
Fig. 3 shows a transportation stage diagram of a claw pump, in which the air cavity, the air suction port and the air exhaust port are not communicated with each other between the rotors, and the volume of air is not changed, so that the transportation process of the compression cavity is realized.
Fig. 4 shows a compression stage diagram of a claw pump, in which the air cavity between the rotors is not communicated with the air suction port and the air exhaust port, but the volume of the air cavity between the rotors is reduced, so as to realize the compression process of the compression cavity.
Fig. 5 shows the exhaust stage of the claw pump, in which the air chamber between the rotors is communicated with the exhaust port to realize the exhaust process of the compression chamber.
Finally, it should be noted that: various modifications and alterations of this invention may be made by those skilled in the art without departing from the spirit and scope of this invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
Claims (6)
1. A double-ended claw pump rotor profile, characterized in that it comprises a rotor 1 and a rotor 2, the rotor 1 and the rotor 2 each having a rotor shaft rotation center O about their own1And the rotor shaft rotation center O2Symmetry;
the upper half part of the rotor profile of the rotor 1 is in point meshing cycloid a1b1Tip to tip rolling arc b1c1C, transition arc1d1Transition arc d1e1Arc e of contact with tooth bottom1f1The upper half part of the rotor profile of the rotor 2 is formed by point meshing cycloid a2b2Round arc b with pairs of tooth bottoms2c2Arc envelope c2d2Arc envelope d2e2And the tooth crest pair rolling arc e2f2Forming;
the rotors 1 and 2 each rotate around the rotor axis rotation center O1And the rotor shaft rotation center O2During synchronous rotation in different directions, points are meshed with cycloids a1b1And point a2Mesh, point b1Cycloidal a engaged with point2b2Meshing, tooth tip to rolling arc b1c1Arc b of contact with tooth bottom2c2Engaging, transition arc c1d1And the arc envelope c2d2Engaging, transition arc d1e1And the arc envelope d2e2Meshing, bottom of tooth pair rolling arc e1f1Arc e of contact with tooth crest2f2Meshing;
the point b1Point a2Is a sharp point, point a1Point c1Point d1Point e1Point f1Point b2Point c2Point d2Point e2Point f2The common tangent points of two adjacent curves form smooth curves, so that the meshing process is stable;
the pitch circle radius of the rotor 1 is r1The pitch circle radius of the rotor 2 is r2The rotor 1 and the rotor 2 are synchronously meshed, and the meshing parameter transmission ratio i is r1/r2The pitch radii of rotor 1 and rotor 2 are equal, i.e. r, to 11＝r2And the center distance A is r1+r2＝2r1。
2. A double-ended claw pump rotor profile according to claim 1, characterised by point-meshing cycloids a1b1Satisfies the following formula:
xab1＝a costab-b cos ctab
yab1＝-(a sin tab-b sin ctab)
point meshing cycloid a2b2Satisfies the following formula:
xab2＝a cos tab-b cos ctab
yab2＝a sin tab-b sin ctab
wherein a is the distance from the center of the rolling circle to the center of the base circle, a is A, and the swing diameter b is Rh，A、RhIs known wherein RhThe radius of the addendum circle is,
c＝a/r1＝2。
3. a double-ended claw pump rotor profile according to claim 1, wherein the addendum is directed towards the rolling arc b1c1Satisfies the following formula:
xbc1＝rbccos tbc
ybc1＝rbcsin tbc
round arc b of gear bottom pair rolling2c2Satisfies the following formula:
xbc2＝(A-rbc)cos tbc
ybc2＝(A-rbc)sin tbc
wherein r isbcIs b is1c1Radius of arc of (d), rbc＝Rh；tbc∈(0,α1)，α1Is b is1c1Arc of (a)1Are known.
4. A double-ended claw pump rotor profile according to claim 1, characterised in that the transition arc c1d1Satisfies the following formula:
xcd1＝(rbc-rcd)cosα1+rcdcos tcd
ycd1＝(rbc-rcd)sinα1+rcd sintcd
circular arc envelope c2d2Satisfies the following formula:
wherein r iscdIs c1d1The radius of the arc of (a) is,
tcd∈(α1,α1+α2)，α2is c1d1Arc of (a)2Are known.
5. A double-ended claw pump rotor profile according to claim 1, characterised in that the transition arc d1e1Satisfies the following formula:
circular arc envelope d2e2Satisfies the following formula:
wherein r isdeIs d1e1The radius of the arc of (a) is,
tde∈(α1+α2,π-α4)。
6. a double-ended claw pump rotor profile according to claim 1, characterised in that the pair of tooth-bottom rolling arcs e1f1Satisfies the following formula:
xef1＝refcos tef
yef1＝refsin tef
tip to tip arc e2f2Satisfies the following formula:
xef2＝(A-ref)cos tef
yef2＝(A-ref)sin tef
wherein r isefIs e1f1Radius of arc of (d), ref＝A-rbc；tef∈(π-α4,π)，α4Is e1f1Arc of (a)4Are known.
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| CN202111656647.6A CN114320921B (en) | 2021-12-30 | 2021-12-30 | Design method of double-head claw pump rotor molded line |
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| CN202111656647.6A CN114320921B (en) | 2021-12-30 | 2021-12-30 | Design method of double-head claw pump rotor molded line |
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| CN113779721A (en) * | 2021-09-08 | 2021-12-10 | 浙江理工大学 | Special claw type vacuum pump molded line design method based on envelope surface correction |
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2021
- 2021-12-30 CN CN202111656647.6A patent/CN114320921B/en active Active
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| CN1676936A (en) * | 2004-03-30 | 2005-10-05 | 肖文伟 | Rotor tooth-profile for screw pump |
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| GB2557681A (en) * | 2016-12-15 | 2018-06-27 | Edwards Ltd | A claw pump and method of operation |
| WO2018132019A2 (en) * | 2017-01-10 | 2018-07-19 | John Fleming | Improvements in rotary claw pumps |
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