CN208734532U - A kind of complete smooth screw rotor of small enclosed volume - Google Patents
A kind of complete smooth screw rotor of small enclosed volume Download PDFInfo
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- CN208734532U CN208734532U CN201821183174.6U CN201821183174U CN208734532U CN 208734532 U CN208734532 U CN 208734532U CN 201821183174 U CN201821183174 U CN 201821183174U CN 208734532 U CN208734532 U CN 208734532U
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- 230000007704 transition Effects 0.000 claims description 51
- 239000011159 matrix material Substances 0.000 claims description 6
- 230000009466 transformation Effects 0.000 claims description 6
- 230000009977 dual effect Effects 0.000 claims description 5
- 230000001360 synchronised effect Effects 0.000 claims description 2
- 238000004804 winding Methods 0.000 claims 1
- 238000000034 method Methods 0.000 abstract description 10
- 230000008569 process Effects 0.000 abstract description 7
- 238000009499 grossing Methods 0.000 abstract 1
- 239000007788 liquid Substances 0.000 description 24
- 238000007789 sealing Methods 0.000 description 4
- 238000005299 abrasion Methods 0.000 description 3
- 238000010992 reflux Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000012938 design process Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 239000012263 liquid product Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
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Abstract
The utility model discloses a kind of complete smooth screw rotors of small enclosed volume, the left side molded line (101) of its left screw rotor (I) includes: 2 sections of circular arcs, 2 sections of elliptic arcs and 2 sections of elliptic arc envelopes, the engagement system of common point and cycloid is replaced by using elliptic arc and its conjugate curves, so that each section of line smoothing connection of profile, obtains complete smooth screw rotor.Two rotors are identical, and can be realized correct engagement, there is lesser enclosed volume in the process of running, make to run more stable.
Description
Technical field
The utility model relates to twin-screw liquid pumps, in particular to are suitable for a kind of small enclosed volume of twin-screw liquid pump
Complete smooth screw rotor.
Background technique
Twin-screw liquid pump is a kind of proof positive displacement liquid pump, and sucking is separated by the active length section of two screw rotors
Chamber and discharge chamber, transmit torque by a pair of of synchromesh gear, seal chamber are made continuously to shift to outlet from suction inlet, realize liquid
Conveying.Common twin-screw liquid pump profile is made of the engagement of point gearing cycloid, and screw rotor generated is deposited
In rough seamed edge, the mechanical characteristic for thereby resulting in Ω type screw rotor is poor, and rotor is easy to happen abrasion, reduces the use of pump
Service life causes the increase of leakage rate, so that the sealing performance of destruction work chamber, reduces the working performance of Quimby pump.
In the Design and manufacturing process of screw pump, the design of screw rotor end face molded line has larger impact to the performance of pump.
For the performance for improving common twin-screw rotor, Chinese patent (patent No. CN201720524780.9) proposes a kind of complete smooth
Quimby pump rotor, which replaces common point gearing cycloid using two sections of circular arcs and its envelope, alleviates at cusp
Wear problem, realize and constitute being smoothly connected and be properly engaged with completely between curve that there is good sealing performance, wear-resisting
The advantages that performance is high, mechanical characteristic is good；But this in the molded line of twin-screw section there are the variation of curvature convex-concave, it is steady to the operation of pump
Qualitative to there is certain influence, capacity utilization decreases.
Utility model content
The utility model to solve the above-mentioned problems, while in order to enrich twin-screw liquid pump screw rotor end face molded line class
Type proposes a kind of complete smooth screw rotor of small enclosed volume.The utility model is replaced using elliptic arc and its conjugate curves
The engagement system of common point and cycloid, is smoothly connected so that realizing between each curved section in profile；And then obtain full light
Sliding screw rotor.In the course of work, screw rotor end face molded line can be realized in the case where synchronizing incorgruous dual AC power movement and correctly nibble
It closes, the engagement between profile becomes line engagement from original point gearing, and then the engagement between screw rotor is by original
Line engagement becomes face engagement；The sealing performance for improving screw rotor reduces the abrasion between rotor, improves screw rotor
Service life；Enclosed volume formed in screw rotor engagement process is also reduced simultaneously, improves twin-screw liquid pump
Performance；It is of great significance to the type of abundant twin-screw liquid pump screw rotor end face molded line with its working performance is improved.
To achieve the goals above, the utility model adopts the following technical solution:
A kind of complete smooth screw rotor of small enclosed volume, including left screw rotor (I) and right screw rotor (II)；Left spiral shell
The left side molded line (101) of bar rotor (I) includes: 2 sections of circular arcs, 2 sections of elliptic arcs and 2 sections of elliptic arc envelopes, by side counterclockwise
To successively are as follows: left tooth root circular arc LAB, a left side the first tooth top elliptic arc envelope BC, left First Transition elliptic arc CD, left First Transition
Elliptic arc envelope DE, the first tooth top elliptic arc EF of a left side, left addendum circle arc FGH, the second tooth top elliptic arc HI of a left side, left second transition
Elliptic arc envelope IJ, the second transition elliptic arc JK of a left side, the second tooth top elliptic arc envelope KL of a left side；The left side molded line
(101) be it is complete smooth, be smoothly connected between adjacent curve, rough tie point be not present；The left side molded line
(101) symmetrical about y-axis；The left side molded line (101) of the left screw rotor (I) and the right side of right screw rotor (II)
Molded line (102) is identical；Left side molded line (101) can in synchronous incorgruous dual AC power movement with right side molded line (102)
Realize correct engagement, left tooth root circular arc LAB, the first tooth top elliptic arc envelope BC of a left side, a left side first in left side molded line (101)
Transition elliptic arc CD, left First Transition elliptic arc envelope DE, the first tooth top elliptic arc EF of a left side, addendum circle arc FGH, left second tooth
Push up elliptic arc HI, the second transition elliptic arc envelope IJ of a left side, the second transition elliptic arc JK of a left side, left second tooth top elliptic arc envelope
KL, respectively with right addendum circle arc fgh, the right side the first tooth top elliptic arc ef, right First Transition elliptic arc in right side molded line (102)
Envelope de, right First Transition elliptic arc cd, the first tooth top elliptic arc envelope bc of the right side, right tooth root circular arc lab, right second tooth top
Elliptic arc envelope kl, the second transition elliptic arc jk of the right side, the second transition elliptic arc envelope ij of the right side, the second tooth top elliptic arc ih of the right side
Correct engagement.
A kind of complete smooth screw rotor of the small enclosed volume, the left side molded line (101) of left screw rotor (I)
Equation is:
1. the equation of the first tooth top elliptic arc EF of a left side are as follows: rEF(t)=MEF·r4(t)
In formula: MEFFor the first rotational transformation matrix, r4(t) it is tooth top elliptic arc (4), as follows:
The equation of the first tooth top elliptic arc envelope BC of a left side are as follows: rBC(t)=MBC·r5(t)
In formula: MBCFor the second rotational transformation matrix, r5(t) tooth top elliptic arc envelope (5), as follows:
More than: m1The major semiaxis of-tooth top elliptic arc (4)；n1The semi-minor axis of-tooth top elliptic arc (4)；- it is first
Intermediate variable is determined by following equation:
The equation of left First Transition elliptic arc CD are as follows: rCD(t)=MCD·r6(t)
In formula: MCDFor third rotational transformation matrix, r6(t) it is transition elliptic arc (6), as follows:
The equation of left First Transition elliptic arc envelope DE are as follows: rDE(t)=MCD·r7(t)
In formula: r7It (t) is transition elliptic arc envelope (7), as follows:
More than: m2The major semiaxis of-transition elliptic arc (6)；n2The semi-minor axis of-transition elliptic arc (6)；- it is second
Intermediate variable is determined by following equation:
L-is O1The length of C,Wherein (x5(t0),y5(t0)) it is tooth top elliptic arc envelope
Line (5) crosses the coordinate of the intersection point C of the tangent line L of origin with it；
t0By following equation solution:
And the angle of tangent line L and y-axis are as follows:
Wherein, α, β, γ are rotation angle, and(xd, yd) it is pitch circle (3) and transition elliptic arc (6) two
The coordinate of the intersection point D of curve；Rotate angle [alpha]=β+γ.
The utility model has the following beneficial effects:
1. using the engagement system of elliptic arc and the conjugate curves of elliptic arc, light between each curved section in realization profile
Slip avoids the abrasion condition of cusp, improves the mechanical characteristic of screw rotor, improves the service life of screw rotor；
2. in the course of work, the engagement between screw rotor becomes face from original line engagement and engages；Screw rod is improved to turn
The wearability and sealing performance of son, improve the service life of screw rotor, reduce the contact line length between screw rotor, thus
Reduce leakage, improves the operational efficiency of pump；
3. reducing enclosed volume formed in screw rotor engagement process, reduce in Quimby pump operational process
Reflux impact, to improve the performance and stability of twin-screw liquid pump；
4. enriching twin-screw liquid pump screw rotor end face molded line type.
Detailed description of the invention
Fig. 1 is the screw rotor end face molded lines of existing Ω shape twin-screw liquid pump.
Fig. 2 for the left screw rotor of twin-screw liquid pump proposed left side molded lines.
Fig. 3 for the left side molded line of the left screw rotor of twin-screw liquid pump proposed generating process figure.
Fig. 4 is that 2 complete smooth profiles engage figure.
Fig. 5 is that the screw rotor end face molded line of existing Ω shape twin-screw liquid pump engages figure.
Fig. 6 is by the engagement figure of the left side molded line of the left screw rotor of twin-screw liquid pump proposed under equal angular.
Fig. 7 is the engagement figure of 2 complete smooth twin-screw liquid pump screw rotors.
In figure: R2- it is pitch radius；R1- it is radius of addendum；R3- it is root radius；m1- tooth top elliptic arc
(4) major semiaxis；n1The semi-minor axis of-tooth top elliptic arc (4)；- it is the first intermediate variable；m2- transition elliptic arc (6)
Major semiaxis；n2The semi-minor axis of-transition elliptic arc (6)；- it is the second intermediate variable；101-left side molded line；102—
Right side molded line；I-left screw rotor；II-right screw rotor；1-root circle；2-outside circles；3-pitch circles；4-tooth tops are ellipse
Circular arc；5-tooth top elliptic arc envelopes；6-transition elliptic arcs；7-transition elliptic arc envelopes；α, beta, gamma-rotation angle.
Specific embodiment:
The utility model is described in further detail with embodiment with reference to the accompanying drawing.
As shown in Figure 1, be existing Ω shape twin-screw liquid pump screw rotor end face molded lines, by tooth root circular arc AB,
Prolate epicycloid BC, epicycloid CD, addendum circle arc DE, epicycloid EF, prolate epicycloid FA composition；Wherein C, D, F, E are point
Point；Due to the presence of cusp, there are curvature mutations for screw rotor end face molded line, reduce the wearability and stress of screw rotor
Energy.
As shown in Fig. 2, for the left side molded lines of the left screw rotor of twin-screw liquid pump proposed, comprising: 2 sections of circles
Arc, 2 sections of elliptic arcs and 2 sections of elliptic arc envelopes, counterclockwise successively are as follows: left tooth root circular arc LAB, left first tooth top are oval
Arc envelope BC, left First Transition elliptic arc CD, left First Transition elliptic arc envelope DE, a left side the first tooth top elliptic arc EF, a left side
Addendum circle arc FGH, the second tooth top elliptic arc HI of a left side, the second transition elliptic arc envelope IJ of a left side, a left side the second transition elliptic arc JK, a left side
Second tooth top elliptic arc envelope KL；The left side molded line (101) is complete smooth profile, between adjacent curve
It is smoothly connected, rough tie point is not present；The left side molded line (101) is symmetrical about y-axis；The left screw rotor
(I) left side molded line (101) is identical with right side molded line (102) of right screw rotor (II)；
As shown in figure 3, the generating process figure of the left side molded line for the left screw rotor of twin-screw liquid pump proposed, step
It is rapid as follows:
1. establishing coordinate system O1Xy, O1For origin；
2. generating root circle (1), outside circle (2), pitch circle (3) by following equation, equation is as follows:
The equation of root circle (1) are as follows:
The equation of outside circle (2) are as follows:
The equation of pitch circle (3) are as follows:
More than: t-is angle parameter, rad；R1- it is radius of addendum, mm；R2- it is pitch radius, mm；R3- it is tooth
Root radius, mm；And 2R2=R1+R3；
3. generating tooth top elliptic arc (4), tooth top elliptic arc envelope (5) by following equation, equation is as follows:
The equation of tooth top elliptic arc (4) are as follows:
The equation of tooth top elliptic arc envelope (5) are as follows:
More than: m1The major semiaxis of-tooth top elliptic arc (4)；n1The semi-minor axis of-tooth top elliptic arc (4)；- it is first
Intermediate variable is determined by following equation:
4. generating transition elliptic arc (6), transition elliptic arc envelope (7) by following equation, each section of curvilinear equation is as follows:
The equation of transition elliptic arc (6) are as follows:
The equation of transition elliptic arc envelope (7) are as follows:
More than: m2The major semiaxis of-transition elliptic arc (6)；n2The semi-minor axis of-transition elliptic arc (6)；- it is second
Intermediate variable is determined by following equation:
L-is O1The length of C, is determined by following methods:
Wherein (x5(t0),y5(t0)) it is that tooth top elliptic arc envelope (5) is excessively former with it
The coordinate of the intersection point C of the tangent line L of point；
t0It is determined by following equation:
And the angle of tangent line L and y-axis
As shown in figure 4,2 complete smooth profiles engage figure, left side molded line (101) and right side molded line (102)
It can be realized correct engagement in synchronizing the movement of incorgruous dual AC power, left tooth root circular arc LAB in left side molded line (101), left the
One tooth top elliptic arc envelope BC, left First Transition elliptic arc CD, left First Transition elliptic arc envelope DE, left first tooth top are ellipse
Circular arc EF, addendum circle arc FGH, the second tooth top elliptic arc HI of a left side, the second transition elliptic arc envelope IJ of a left side, left second transition are oval
Arc JK, the second tooth top elliptic arc envelope KL of a left side, respectively with right addendum circle arc fgh, right first tooth in right side molded line (102)
Push up elliptic arc ef, right First Transition elliptic arc envelope de, right First Transition elliptic arc cd, right first tooth top elliptic arc envelope
Bc, right tooth root circular arc lab, the second tooth top elliptic arc envelope kl of the right side, the second transition elliptic arc jk of the right side, right second transition elliptic arc
Envelope ij, right second tooth top elliptic arc ih correct engagement.
As shown in Figure 5, Figure 6, respectively existing Ω shape twin-screw liquid pump screw rotor end face molded line engagement figure and
Engagement figure by the left side molded line of the left screw rotor of twin-screw liquid pump proposed under equal angular；The presence of enclosed volume
It will lead to working rotor and generate closed working chamber in the process, and due to the Incoercibility of liquid, will lead to liquid product phenomenon, make
It is impacted at reflux, extreme influence is generated to the stable operation of Quimby pump；The full light of the small enclosed volume as proposed in Fig. 6
The enclosed volume of sliding screw rotor during the work time holds compared with the closing of Ω shape Quimby pump existing in Fig. 5 during the work time
Product is smaller, so, the complete smooth screw rotor of the small enclosed volume proposed has more stable operating condition, higher work effect
Rate and longer service life.
As shown in fig. 7, for the engagement figure of 2 complete smooth twin-screw liquid pump screw rotors.Left screw rotor (I) and the right side
Screw rotor (II) is unfolded to generate by corresponding section molded line along the axis spiral of two screw rotors respectively, the adjacent flank of tooth
Between be completely smooth connection；When two screw rotors synchronize the movement of incorgruous dual AC power, it is able to satisfy nibbling completely for the corresponding flank of tooth
It closes, there is no the parts for interfering or having neither part nor lot in engagement.
It is above-mentioned although specific embodiments of the present invention are described with reference to the accompanying drawings, but it is not practical new to this
The limitation of type protection scope, those skilled in the art should understand that, based on the technical solution of the present invention, ability
Field technique personnel do not need to make the creative labor the various modifications or changes that can be made still in the protection model of the utility model
Within enclosing.
Claims (2)
1. a kind of complete smooth screw rotor of small enclosed volume, including left screw rotor (I) and right screw rotor (II)；Its feature
Be: the left side molded line (101) of left screw rotor (I) includes: 2 sections of circular arcs, 2 sections of elliptic arcs and 2 sections of elliptic arc envelopes, by inverse
Clockwise is successively are as follows: left tooth root circular arc LAB, the first tooth top elliptic arc envelope BC of a left side, left First Transition elliptic arc CD, left the
One transition elliptic arc envelope DE, the first tooth top elliptic arc EF of a left side, left addendum circle arc FGH, the second tooth top elliptic arc HI of a left side, left the
Two transition elliptic arc envelope IJ, the second transition elliptic arc JK of a left side, the second tooth top elliptic arc envelope KL of a left side；The left side
Molded line (101) be it is complete smooth, be smoothly connected between adjacent curve, rough tie point be not present；The left side
Molded line (101) is symmetrical about y-axis；The left side molded line (101) of the left screw rotor (I) and the right side of right screw rotor (II)
Profile (102) is identical；Left side molded line (101) is with right side molded line (102) in synchronous incorgruous dual AC power movement
It can be realized correct engagement, left tooth root circular arc LAB, a left side the first tooth top elliptic arc envelope BC, a left side in left side molded line (101)
First Transition elliptic arc CD, left First Transition elliptic arc envelope DE, the first tooth top elliptic arc EF of a left side, addendum circle arc FGH, left the
Two tooth top elliptic arc HI, the second transition elliptic arc envelope IJ of a left side, the second transition elliptic arc JK of a left side, left second tooth top elliptic arc packet
Winding thread KL, it is ellipse with right addendum circle arc fgh, the first tooth top elliptic arc ef of the right side, the right First Transition in right side molded line (102) respectively
Arc envelope line de, right First Transition elliptic arc cd, the first tooth top elliptic arc envelope bc of the right side, right tooth root circular arc lab, the right side second
Tooth top elliptic arc envelope kl, the second transition elliptic arc jk of the right side, the second transition elliptic arc envelope ij of the right side, right second tooth top are oval
Arc ih correct engagement.
2. a kind of complete smooth screw rotor of small enclosed volume as described in claim 1, the left side of left screw rotor (I)
Molded line (101) is characterized in:
1) equation of the first tooth top elliptic arc EF of a left side are as follows: rEF(t)=MEF·r4(t)
In formula: MEFFor the first rotational transformation matrix, r4(t) it is tooth top elliptic arc (4), as follows:
The equation of the first tooth top elliptic arc envelope BC of a left side are as follows: rBC(t)=MBC·r5(t)
In formula: MBCFor the second rotational transformation matrix, r5(t) tooth top elliptic arc envelope (5), as follows:
More than: m1The major semiaxis of-tooth top elliptic arc (4)；n1The semi-minor axis of-tooth top elliptic arc (4)；- it is among first
Variable is determined by following equation:
The equation of left First Transition elliptic arc CD are as follows: rCD(t)=MCD·r6(t)
In formula: MCDFor third rotational transformation matrix, r6(t) it is transition elliptic arc (6), as follows:
The equation of left First Transition elliptic arc envelope DE are as follows: rDE(t)=MCD·r7(t)
In formula: r7It (t) is transition elliptic arc envelope (7), as follows:
More than: m2The major semiaxis of-transition elliptic arc (6)；n2The semi-minor axis of-transition elliptic arc (6)；- it is among second
Variable is determined by following equation:
L-is O1The length of C,Wherein (x5(t0),y5(t0)) it is tooth top elliptic arc envelope
(5) coordinate of the intersection point C for the tangent line L for crossing origin with it；
t0By following equation solution:
And the angle of tangent line L and y-axis are as follows:
Wherein, α, β, γ are rotation angle, and(xd, yd) it is pitch circle (3) and (6) two songs of transition elliptic arc
The coordinate of the intersection point D of line；Rotate angle [alpha]=β+γ.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201821183174.6U CN208734532U (en) | 2018-07-25 | 2018-07-25 | A kind of complete smooth screw rotor of small enclosed volume |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201821183174.6U CN208734532U (en) | 2018-07-25 | 2018-07-25 | A kind of complete smooth screw rotor of small enclosed volume |
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| CN208734532U true CN208734532U (en) | 2019-04-12 |
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| CN201821183174.6U Expired - Fee Related CN208734532U (en) | 2018-07-25 | 2018-07-25 | A kind of complete smooth screw rotor of small enclosed volume |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108757438A (en) * | 2018-07-25 | 2018-11-06 | 中国石油大学(华东) | A kind of complete smooth screw rotor and its design method of small enclosed volume |
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- 2018-07-25 CN CN201821183174.6U patent/CN208734532U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108757438A (en) * | 2018-07-25 | 2018-11-06 | 中国石油大学(华东) | A kind of complete smooth screw rotor and its design method of small enclosed volume |
| CN108757438B (en) * | 2018-07-25 | 2023-08-18 | 中国石油大学(华东) | Full-smooth screw rotor with small enclosed volume and design method thereof |
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