CN1904365B - Claw type rotor design method - Google Patents

Abstract

The present invention discloses a claw rotor design method, which can design a defined rotor and a conjugate rotor that are mutually conjugately meshed, and parameterize the motion curves of the two rotors from ineffective compression to the start of intake, and the motion curves from the start of exhaust to the end, so as to evaluate and find the optimal rotor performance. The method can be applied to vacuum pumps, air compressors, compressors, superchargers, etc. that meet actual needs to provide a higher compression ratio and delivery volume, and ensure that no noise or vibration occurs during the operation of the two rotors.

Description

Claw Rotor Design Method

technical field

The present invention relates to a claw-type rotor design method, which is an additional patent application of Taiwan New Patent No. 220027 (compared to the Continuation In Part of U.S. Patent No. 6,776,594; CIP). With the conjugate rotor, four parameters are used to define the motion curve of the two rotors from invalid compression to the beginning of intake, and the motion curve from the beginning to the end of exhaust, so as to evaluate and find the best rotor performance, which can be applied to vacuum pumps, air pressure Machines, compressors, superchargers, etc., to provide a higher compression ratio and delivery volume, and to make the intake and exhaust movement process smooth without noise and vibration.

Background technique

Claw rotors applied to multi-stage compressors, vacuum pumps, air compressors or superchargers generally include: two meshing defined rotors and conjugate rotors, and the two rotors are respectively provided with meshing blades , through the two blades meshing with each other to provide a periodic cycle of intake and exhaust compression movement, therefore, the meshing of the two blades is very important, if the two blades mesh with each other poorly, in the periodic cycle of intake, exhaust, and non-compression Noise and vibration will be generated during the rotation process, and it will also cause wear and tear of the two rotors due to improper meshing, thereby reducing the service life.

The structure of known related rotors can refer to U.S. Patent Nos. 1,426,820, 4,138,848, 4,224,016, 4,324,538, 4,406,601, 4,430,050 and 5,149,256, etc., wherein the blades of the two rotors 8 and 9 of No. 5,149,256, as shown in FIG. , 90 and the arc surface 81, 91 at the intersection of the tip 82, 92, so that the curve of the entire rotor 80, 90 forms a discontinuity at the tip 82, 92, so when it is from invalid compression to the start of intake During the process, the tip portions 83, 93 of the rotors 8, 9 will not run smoothly at the tip portions 82, 92, and noise and vibration will occur. In the same situation, the aforementioned other U.S. patents also have the phenomenon of unsmooth operation and noise and vibration during the actuation process of the two meshing rotors.

The Taiwan New Patent No. 220027 (U.S. Patent No. 6,776,594) before this case has proposed to solve the defects of the above-mentioned known technology, that is, in the stage from the invalid compression of the two rotors to the start of intake air, and the stage from the beginning to the end of exhaust , formed by the smooth connection of two different curves, rather than the intersection of two arcs. Therefore, it is possible to prevent the occurrence of noise and vibration during the operation of the two rotors.

Contents of the invention

The purpose of the present invention is to provide a claw-type rotor design method, which can combine the motion curves from the invalid compression to the start of air intake and the motion curve from the beginning to the end of exhaust of the mutually meshed definition rotor and conjugate rotor with different parameters The definition is obtained, so as to evaluate and obtain the best rotor performance, and can be applied to vacuum pumps, air compressors, compressors, superchargers, etc. that are actually required to provide a higher compression ratio and delivery volume, and to ensure that the two rotors are in the same position. There will be no noise and vibration during the operation.

For this reason, the present invention proposes a claw-type rotor design method, which is used to manufacture defined rotors and conjugate rotors that are conjugated and meshed with each other, and parametrically design the parameters including curve E, arc A, arc B, and arc F. , the arc C, the straight line Y define the body and the blade of the rotor, and form the conjugate rotor with the conjugate curve from the curve and the arc, the method includes: forming the step of defining the rotor and forming the step of the conjugate rotor, wherein:

The forming defined rotor steps include:

Specify the maximum radius R of the defined rotor, the width D of the defined rotor, the pitch circle radius Rp of the defined rotor and the conjugate rotor, and the centers t1 and t3 of the two pitch circles. The center distance between the two pitch circles is 2Rp, Rp is smaller than R, and R and There is an appropriate ratio between the two Rp;

Take the center t1 of the pitch circle as the center of the defined rotor, pass a horizontal line h1, and obtain a point P ₀ on the horizontal line h1, the horizontal distance between this point P ₀ and the center t1 is R, and circle the center of the pitch circle from this point P ₀ t1 produces a conjugate curve E', which is a symmetric curve E with respect to the intersection point _P1 of the two pitch circles, and this curve E is taken as a part of the blade of the rotor. the intersection point _P3 of this curve E on the horizontal line h1;

From the horizontal line h1 and the center angle α defining the rotor center t1, another point P ₁ defining the rotor motion curve is determined. Connecting the aforementioned points P ₀ and P ₁ can obtain the arc A defining the rotor profile curve, which is smoothly connected with the curve E ;

Obtain the second center point t2 on the side h2 of the center angle α, and obtain the radius r _B of the second center point t2 through the trigonometric function relational formula, then a circular arc B can be obtained as another definition of the outer shape curve of the rotor part, and obtain the two endpoints P ₁ and P ₂ of the arc B, and the vertical position of point P ₂ above the center t2;

Take a point t3 on the horizontal line h1 relative to the center t1 that defines the pitch circle of the rotor as the center point of the pitch circle of the conjugate rotor, and the horizontal distance between t3 and t1 is 2Rp, then a point _P4 that defines another shape curve of the rotor can be obtained by passing The conjugate rotor center t3 is determined by the radius R and the specified central angle β, connecting the aforementioned point _P3 and point _P4 can obtain another shape curve arc F defining the rotor;

Obtain the fourth center point t4 on the side h3 of the center angle β, and obtain the radius r _C of the fourth center point t4 through the trigonometric function relational expression, then a circular arc C can be obtained as another definition of the outer shape curve of the rotor part, and obtain the two endpoints of the arc C, point P ₄ and point P ₅ , and the vertical position of point P ₅ below the center of the circle t4;

The horizontal straight line Y formed by the symmetrical point _P6 connecting point _P2 and point _P5 ; connecting the above-mentioned curve E, arc A, arc B, arc F, arc C, and straight line Y to define the rotor 1 unit The shape curve of the claw is symmetrical to the shape curve of the other claw and the above-mentioned definition curves, so it is the body shape curve that defines the rotor;

The step of forming a conjugate rotor is to use the above steps to determine and define the shape of the rotor, and then to define the conjugate curves of the defined curves in the rotor.

Description of drawings

Fig. 1 is a schematic diagram of the end-point conjugate curve formed by the claw rotor design method of the present invention.

Fig. 2 is a schematic diagram of defining the shape of the rotor formed by the claw rotor design method of the present invention.

3 is a schematic diagram of an application example of the claw rotor design method of the present invention, wherein the maximum rotor radius R is defined as 60mm, the rotor width D is defined as 85mm, the central angle α is 3 degrees, and the central angle β is 6 degrees.

Fig. 4 is a schematic diagram of the shape of a conjugate rotor formed by the claw rotor design method of the present invention.

Fig. 5 is a schematic diagram of defining the shape change of the rotor when the thickness D of the rotor is defined as 52, 55, 60, 65, 75, and 80 mm in the claw rotor design method of the present invention.

Fig. 6 is a schematic diagram of defining the change of the shape of the rotor when the central angle α is 3, 6, 9, and 12 degrees in the claw rotor design method of the present invention.

Fig. 7 is a schematic diagram of defining the shape change of the rotor when the central angle β is 3, 6, 9, and 12 degrees in the claw rotor design method of the present invention.

Fig. 8 is a tabulation of the different values of the blades of the defined rotor and the conjugate rotor obtained by different parameters in Figs. 4, 6, and 7.

Figure 9 is a plan view of US Patent No. 5,149,256.

Explanation of reference signs:

Define Rotor 1 Conjugate Rotor 2 Maximum Radius R

Define rotor width D pitch circle radius Rp straight line Y

Center t1, t2, t3, t4 Horizontal line h1, h2, h3, h4

Point P ₀ , P ₁ , P ₂ , P ₃ , P ₄ , P ₅ , P ₆ , P ₇ central angle α, β

Radius r _B , r _C Curve E, E' Arc A, B, C, F

Detailed ways

The claw-type rotor design method of the present invention first obtains the shape of the defined rotor 1, and then obtains the shape of the conjugated rotor 2 using the conjugate curve, please refer to Figures 1 and 2. The shape of the defined rotor 1 includes the following steps:

1. Define the maximum radius R of the rotor, define the width D of the rotor, define the pitch circle radius Rp of the rotor and the conjugate rotor, the centers of the two pitch circles are t1 and t2 respectively, Rp is less than R, and define the maximum radius R of the rotor The ratio of the circle radius Rp is R=3Rp/2.

2. Take the center t1 of the pitch circle as the center of the defined rotor, pass through a horizontal line h1, and obtain a point P ₀ on the horizontal line h1, the horizontal distance between this point P ₀ and the center of the circle t1 is R, and wind around the node by this point P ₀ The center of the circle t1 produces a conjugate curve E', which is a symmetrical curve E with respect to the pitch circle intersection point _P7 , and this curve E is taken as a part of the blade of the rotor. The intersection point _P3 of this curve E on the horizontal line h1.

3. Another point P ₁ defining the rotor profile curve is determined by defining the rotor center t1 with the radius R and the designated center angle α. The arc A can be obtained by connecting the points P ₀ and P ₁ .

4. Take the side h2 with the central angle α, and get a center point t2 on the side h2 with a radius of r _B .

5. The radius r _B is obtained as follows: (wherein R = defines the maximum radius of the rotor; that is, the length from the center of circle t1 to point _P1 )

${\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; D.</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}$

${\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; B</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; D.</span>}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}$

6. Obtain the radius r _B and then take the center of the circle t2 as the center, then the arc B whose two ends are point P ₁ and point P ₂ can be obtained as another part of the profile curve defining the rotor, and the point P ₂ is above the center of the circle t2 vertical position.

7. Obtain the pitch circle center t3 of the conjugate rotor on the horizontal line h1, the horizontal distance between t1 and t3 is 2Rp, then another point _P4 defining the rotor profile curve can be obtained by passing through the conjugate rotor center t3 with the radius R and the specified The central angle β is determined. The contour curve obtained by connecting the point _P3 and the point _P4 is an arc F.

8. Take the side h3 of the central angle β, and obtain a center point t4 on the side h3 with a radius of r _C .

9. The radius r _C is obtained as follows: (wherein R = defines the maximum radius of the rotor; that is, the length from the center of circle t3 to point _P4 )

${\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; C</span>}}<span\; class="notranslate">\; +</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; R</span>}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; C</span>}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; D.</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}}$

${\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; C</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; D.</span>}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; R</span>}\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&beta;</span>}}{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; sin</span>}\mathrm{<span\; class="notranslate">\; \&beta;</span>}}$

10. Obtain the radius r _C and then take the center t4 as the center of the circle, then the arc C whose two ends are point P ₄ and point P ₅ can be obtained as another part of the profile curve defining the rotor, and the point P ₅ is perpendicular to the center t4. Location.

11. A horizontal straight line Y formed by the symmetrical point _P6 connecting the point _P2 and the point _P5 .

12. Connect the above-mentioned curve E, arc A, arc B, arc F, arc C, straight line Y, etc. to form the profile curve defining the single claw of rotor 1, and the profile curve of the other claw is consistent with the above-mentioned defined curves. Symmetrical relationship (shown by dotted lines).

Therefore, through the above-mentioned steps, a defined profile curve of the rotor body with two-claw blades can be obtained.

Please refer to Fig. 3, after using the above steps to determine and define the shape of the rotor 1, the shape of the conjugate rotor 2 is then defined by the above-mentioned respective definition curves of the rotor 1 (curve E, arc A, arc B, arc F, arc C. The conjugate curve of straight line Y).

Please refer to Fig. 4 for the application example of the claw rotor design method of the present invention, wherein the maximum rotor radius R is defined as 60mm, the rotor width D is defined as 85mm, the central angle α is 3 degrees, and the central angle β is 6 degrees, as shown in the figure. Under these conditions, the shapes of the defined rotor 1 and the conjugated rotor 2 are almost the same, therefore, they have relatively similar mechanical properties in practical applications.

Please refer to Figure 5 again. When the maximum radius R of the rotor is defined as 60mm and remains unchanged, and the width D of the rotor 1 is defined as 52, 55, 60, 65, 70, 75, and 80 mm, according to the characteristics of conjugate meshing, It is defined that the smallest value of the width D of the rotor 1 (S1) corresponds to the largest shape of the conjugated rotor 2 (L1), and so on, and corresponding adjustments can be made as required in practical applications.

In addition, please refer to Figs. 6 and 7, in the claw rotor design method of the present invention, 60 mm is used to maintain the maximum radius R of the rotor 1, and 85 mm is used to define the rotor width D, and the central angle α and the central angle β are respectively 3, 6, 9, When it is 12 degrees, there are different changes in the definition of the shape of the rotor 1. It can be clearly shown from the figure that when the central angle α is at different angles, the outer side of the blade defining the rotor 1 will increase with the increase of the angle (Fig. 6), while the conjugated rotor 2 becomes smaller as the angle becomes larger. Similarly, when the central angle β is at different angles, the other outer side of the blade defining the rotor 1 will increase as the angle increases, while the conjugate rotor 2 will decrease as the angle increases (Figure 7) . Please refer to Fig. 8, which is a collection of Fig. 5 to Fig. 7. Different definitions of the width D of the rotor 1 and different central angles α and β are used to obtain different parameter values of the radius r _B and radius r _C. According to these parameter values, The shapes of the defined rotor 1 and the conjugated rotor 2 can be adjusted relative to each other.

The defined rotor 1 and the conjugated rotor 2 produced by the method of the present invention, in the stages from the ineffective compression to the start of intake and the stage from the beginning to the end of the exhaust, are smoothly connected by two different curves, Therefore, it is possible to avoid noise and vibration during the operation of the two rotors, and it has a relatively high compression ratio and delivery volume.

However, the above-mentioned ones are only preferred embodiments of the present invention, and all modifications and changes made according to the present invention should still be included in the scope of the patent application of this case.

Claims (2)

1. designing method of claw type rotor, this method is used to make the definition rotor and the conjugation rotor of mutual conjugation engagement, design the body and the blade of the definition rotor that comprises curve E, circular arc A, circular arc B, circular arc F, circular arc C, straight line Y with parametrization, and form the conjugation rotor with conjugate curve by described curve, circular arc and straight line, this method comprises: forms definition rotor step and forms conjugation rotor step, wherein:

This formation definition rotor step comprises:

Specify definition rotor maximum radius R, the width D of definition rotor, definition rotor and the Pitch radius Rp of conjugation rotor and the center of circle t1 of this two pitch circle, t3, this two centre of pitch circle distance is 2Rp, Rp is less than R, and R and Rp the two a proper proportion is arranged;

Get the center of circle of the center of circle t1 of pitch circle,, and on this horizontal line h1, obtain 1 P by a horizontal line h1 as the definition rotor ₀, this P ₀With the horizontal equivalent of center of circle t1 be R, by this P ₀Produce conjugate curve E ' around center of circle t1, curve E ' is with respect to two pitch circle intersection point P ₇Symmetrical curve E, get the blade part of this curve E as rotor; The intersection point P of this curve E on horizontal line h1 ₃

With radius R and specified central angle alpha, decision defines another P of rotor motion curve by this horizontal line h1, center of circle t1 ₁, connect aforementioned some P ₀With P ₁Can obtain the circular arc A of definition rotor contour, and be connected with curve E is smooth-going;

On the contained side h2 of this central angle alpha, obtain the second centre point t2, and try to achieve the radius r of the second centre point t2 via the trigonometric function relation _B, then can obtain one is the circular arc B in center of circle another part of appearance curve as the definition rotor with the second centre point t2, and obtains two end points P of this circular arc B ₁With P ₂, and some P ₂Vertical position above the t2 of the center of circle;

The center of circle t1 that goes up with respect to definition rotor pitch circle in this horizontal line h1 gets the centre point of 1 t3 as conjugation rotor pitch circle, and the horizontal equivalent of center of circle t3 and center of circle t1 is 2Rp, then defines 1 P of another appearance curve of rotor ₄Can connect aforementioned some P by determining with radius R and specified central angle β by center of circle t3 ₃With a P ₄Can obtain another appearance curve circular arc F of definition rotor;

On the contained side h3 of this central angle β, obtain the 4th centre point t4, and try to achieve the radius r of the 4th centre point t4 via the trigonometric function relation _C, then can obtain one is the circular arc C in center of circle another part of appearance curve as the definition rotor with the 4th centre point t4, and obtains two end point P of this circular arc C ₄With a P ₅, and some P ₅Vertical position below the t4 of the center of circle;

Tie point P ₂An and P ₅Symmetric points P ₆Formed horizontal linear Y; The appearance curve that connects above-mentioned curve E, circular arc A, circular arc B, circular arc F, circular arc C, straight line Y composition definition rotor (1) monodactyle, the appearance curve of another pawl becomes symmetric relation with the appearance curve of above-mentioned monodactyle relatively, so for defining the body appearance curve of rotor;

This formation conjugation rotor step is, utilize the profile of above-mentioned steps decision definition rotor after, the profile of conjugation rotor then is made up of the conjugate curve that respectively define curve in the above-mentioned definition rotor;

Described radius r _BBe to try to achieve by following trigonometric function relation:

$r_B+(R-r_B)\sin \mathrm{\&alpha;}=\frac{D}{2}$

$r_B=\frac{D/2-R\sin \mathrm{\&alpha;}}{1-\sin \mathrm{\&alpha;}}$

Wherein R=defines the maximum radius of rotor; Be that center of circle t1 is to putting P ₁Length;

Described radius r _CBe to try to achieve by following trigonometric function relation:

$r_C+(R+r_C)\sin \mathrm{\&beta;}=\frac{D}{2}$

$r_C=\frac{D/2-R\sin \mathrm{\&beta;}}{1+\sin \mathrm{\&beta;}}$

Wherein R=defines the maximum radius of rotor; Be that center of circle t3 is to putting P ₄Length.

2. designing method of claw type rotor according to claim 1 is characterized in that the ratio of described definition rotor maximum radius R and Pitch radius Rp is R=3Rp/2.

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