A rotary tooth compressor

Abstract

A rotary tooth compressor includes a male rotor and a female rotor that mesh with each other. The male rotor has an outer convex profile, and the female rotor has an inner concave profile. The male rotor and the female rotor are arranged inside a cylinder. An intake port is radially provided on the cylinder, and an exhaust port is axially provided on the cylinder. The cross-section of the outer convex profile consists of an arc portion and an outer convex portion connected to the arc portion. The cross-section of the inner concave profile consists of an arc portion and an inner concave portion connected to the arc portion. The outer convex portion is composed of sequentially connected curve segments CB, BA, AD, and DE. The inner concave portion is composed of sequentially connected curve segments IH, HG, GJ, and JK. The curve segments BA, AD, and point D correspond to the curve segments HG, GJ, and JK and conform to the analytical envelope relationship. The curve segments IH, KI, and point K correspond to the curve segments CB, EC, and DE and conform to the analytical envelope relationship. The present invention avoids the generation of internal leakage channels, has a longer intake time and internal compression time, and can achieve a very high exhaust pressure.

Description

Technical Field

[0001] The present invention belongs to the technical field of compressors, and particularly relates to a rotary tooth compressor. Background Art

[0002] Rotary compressors belong to a type of positive displacement compressors, and rely on the working volume to rotate around the rotor to achieve the increase of gas pressure. Rotary compressors have many advantages such as long service life of rotary machinery, small vibration, and stable operation. At the same time, they have characteristics such as high energy efficiency, no vulnerable parts such as air valves, forced suction and exhaust, and simple structure. At present, the more common rotary compressors include screw compressors, scroll compressors, roots blowers, and sliding vane compressors, etc., and are widely used in modern industry.

[0003] Twin-rotor compressors integrate the advantages of small vibration and stable operation of rotary compressors, and are widely used in industrial air compression, refrigeration and air conditioning, pharmaceutical and food processing and other fields. The most core component of twin-rotor compressors is the rotor. At the same time, the design of the rotor profile determines the structure of the rotor, thus affecting the overall operating performance of the compressor. The innovative design of the rotor is the key technology for manufacturing rotary compressors.

[0004] For twin-rotor compressors, there is a close relationship between the rotor profile and internal leakage. This leakage will cause energy loss, efficiency decline and reduce system performance. Imperfect rotor profile design may lead to the formation of leakage channels. Summary of the Invention

[0005] The purpose of the present invention is to provide a rotary tooth compressor for the problems in the above-mentioned prior art, which can achieve a higher pressure ratio, minimize the leakage channels to the greatest extent, and improve the efficiency of the compressor.

[0006] In order to achieve the above purpose, the present invention has the following technical solutions:

[0007] A rotary tooth compressor includes a male rotor and a female rotor that mesh with each other. The male rotor has an outer convex profile, and the female rotor has an inner concave profile. The male rotor and the female rotor are arranged inside a cylinder. The cylinder has two intersecting circular cylinder bores that respectively accommodate the male rotor and the female rotor. The cylinder is radially provided with an air inlet port, and axially provided with an air outlet port. The air inlet port and the air outlet port communicate with the circular cylinder bores. The cross-section of the outer convex profile of the male rotor consists of an arc portion and an outer convex portion connected to the arc portion. The cross-section of the inner concave profile of the female rotor consists of an arc portion and an inner concave portion connected to the arc portion. The outer convex portion is composed of sequentially connected curve segments CB, BA, AD, and DE. The inner concave portion is composed of sequentially connected curve segments IH, HG, GJ, and JK. The curve segments BA, AD, and point D correspond to the curve segments HG, GJ, and JK, respectively, and conform to the analytical envelope relationship. The curve segments IH, KI, and point K correspond to the curve segments CB, EC, and DE, respectively, and conform to the analytical envelope relationship.

[0008] As a preferred solution, the curve segment BA is a pin tooth arc with a radius of R, and the curve segment IH is an arc with a radius of R1. The parametric equation of the curve segment BA is:

[0009]

[0010] where

[0011]

[0012] In the formula, the pitch circle radii of the male rotor (1) and the female rotor (2) are r p1 and r p2 ;

[0013] The curve segment HG is the conjugate curve segment of the curve segment BA. The parametric equation of the curve segment HG is:

[0014]

[0015] As a preferred solution, the parametric equation of the curve segment AD is:

[0016]

[0017] The curve segment GJ is the conjugate curve segment of the curve segment AD. The parametric equation of the curve segment GJ is:

[0018]

[0019] In the formula, ε is the central angle of the curve segment AD.

[0020] As a preferred solution, the coordinates of point D are ((r p1 +R)cosε, (r p1 +R)sinε);

[0021] The parametric equation of the curve segment JK is:

[0022]

[0023] Wherein, is an intermediate variable,

[0024]

[0025]

[0026] Wherein, A is the center O of the male rotor (1) m and the center O of the female rotor (2) f The distance between them.

[0027] As a preferred solution, substituting into the parametric equation of the curve segment JK to obtain the coordinates of point K. The parametric equation of the coordinates of point K is:

[0028]

[0029] As a preferred solution, the parametric equation of the curve segment DE is:

[0030]

[0031] Wherein, is an intermediate variable, Among them:

[0032]

[0033]

[0034] As a preferred solution, the parametric equation of the curve segment IH is:

[0035]

[0036] Among them,

[0037]

[0038] As a preferred solution, the curve segment CB is the envelope segment of the curve segment IH. The parametric equation of the curve segment CB is:

[0039]

[0040] Among them, θ ∈ (-γ, α), and the intermediate variable is expressed as:

[0041]

[0042] As a preferred solution, the parametric equation of the curve segment KI is:

[0043]

[0044] The curve segment EC is the conjugate curve segment of the curve segment KI, and the parametric equation of the curve segment EC is:

[0045]

[0046] As a preferred solution, the position of the air inlet orifice is solved by the following formula:

[0047]

[0048] In the formula, μ is the angle size of the upper edge point of the air inlet orifice deviating from the x-axis; ι is the angle size of the point P on the meshing line deviating from the x-axis, and the solution expression is as follows:

[0049]

[0050] The exhaust orifice is composed of four circular arc curves of the curve segments PN, NS, ST, and TP, where:

[0051] The parametric equation of the curve segment PN is:

[0052]

[0053] The curve segment NS is a trajectory line of the curve segment GJ during rotation, and the parametric equation is:

[0054]

[0055] The parametric equations of the curve segments TP and ST are respectively:

[0056]

[0057]

[0058] Compared with the prior art, the present invention has at least the following beneficial effects:

[0059] The compression process of gas is realized through two meshing rotor structures. Compared with the existing double-rotor compressor structures, in the rotary tooth compressor of the present invention, the two rotors are fully meshed in space. Especially in cooperation with the designed suction port and discharge port, the intake and exhaust losses are minimized, and the generation of internal leakage channels is avoided. In addition, the rotary compressor applying the rotor structure of the present invention has a long intake time and internal compression time, enabling the gas to be compressed to a very small volume before being discharged, achieving a very high discharge pressure and greatly increasing the pressure ratio. And due to the reasonable profile design, the generation of internal leakage channels during the compression process is avoided, improving the compression efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 Schematic diagram of the structure of the rotary tooth compressor according to an embodiment of the present invention;

[0061] Fig. 2(a) Schematic diagram of the profile of the male rotor of the rotary tooth compressor according to an embodiment of the present invention;

[0062] Fig. 2(b) Schematic diagram of the profile of the female rotor of the rotary tooth compressor according to an embodiment of the present invention;

[0063] Fig. 3(a) Schematic diagram of the meshing relationship of the rotor profiles according to an embodiment of the present invention;

[0064] Fig. 3(b) Schematic diagram of the meshing line of the rotors according to an embodiment of the present invention;

[0065] Figure 4 Schematic diagram of the design parameters of the rotor profiles according to an embodiment of the present invention;

[0066] Fig. 5(a) Schematic diagram of the suction port of the rotary tooth compressor according to an embodiment of the present invention;

[0067] Fig. 5(b) Schematic diagram of the discharge port of the rotary tooth compressor according to an embodiment of the present invention;

[0068] Figure 6 Schematic diagram of the working process of the rotary tooth compressor according to an embodiment of the present invention;

[0069] Figure 7 Schematic diagram of the discharge process of the rotary tooth compressor according to an embodiment of the present invention;

[0070] In the drawings: 1 - male rotor; 2 - female rotor; 3 - cylinder; 4 - suction port; 5 - discharge port. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0071] The present invention will be further described in detail below with reference to the drawings.

[0072] As Figure 1As shown in the figure, the rotary gear compressor according to the embodiment of the present invention includes a male rotor 1 and a female rotor 2 that mesh with each other. The male rotor 1 has an outer convex profile, and the female rotor 2 has an inner concave profile. The male rotor 1 and the female rotor 2 are arranged inside a cylinder 3. The cylinder 3 has two intersecting circular cylinder holes for accommodating the male rotor 1 and the female rotor 2 respectively. An air inlet port 4 is radially provided on the cylinder 3, and an air outlet port 5 is axially provided on the cylinder 3. The air inlet port 4 and the air outlet port 5 communicate with the circular cylinder holes. The cross-section of the outer convex profile of the male rotor 1 is composed of an arc portion and an outer convex portion connected to the arc portion. The cross-section of the inner concave profile of the female rotor 2 is composed of an arc portion and an inner concave portion connected to the arc portion. During the meshing rotation of the male rotor 1 and the female rotor 2 with each other, the processes of air intake, compression, and exhaust can be realized.

[0073] As shown in FIGS. 2(a) and 2(b), in the male rotor 1 and the female rotor 2 that mesh with each other according to the embodiment of the present invention, the outer convex portion of the male rotor 1 is composed of sequentially connected curve segments CB, BA, AD, and DE, and the inner concave portion of the female rotor 2 is composed of sequentially connected curve segments IH, HG, GJ, and JK. The curve segments BA, AD, and point D correspond to the curve segments HG, GJ, and JK and conform to the analytical envelope relationship. The curve segments IH, KI, and point K correspond to the curve segments CB, EC, and DE and conform to the analytical envelope relationship.

[0074] The meshing position of the profiles of the male and female rotors and the meshing line of the corresponding line segments are shown in FIGS. 3(a) and 3(b). As Figure 4 shown, the distance between the centers O m and O f of the two rotors is A. The pitch circle radii of the two rotors are r p1 and r p2 respectively, and they are equal in size. The curve AB on the male rotor is a pin tooth arc with a radius of R, and the curve HI on the female rotor is a small arc with a radius of R1.

[0075] The parametric equation of the curve segment AB is:

[0076]

[0077] where

[0078]

[0079] The conjugate curve segment of the curve segment AB, that is, the curve segment GH, has the following parametric equation:

[0080]

[0081] It can be seen that the curve segment GH is also a pin tooth arc.

[0082] The parametric equation of the curve segment AD on the male rotor is:

[0083]

[0084] The conjugate curve segment of the curve segment AD is the curve segment GJ, and the parametric equation of the curve segment GJ is:

[0085]

[0086] The coordinates of point D on the male rotor are ((r p1 +R)cosε, (r p1 +R)sinε), and the parametric equation of the curve segment JK is:

[0087]

[0088] It can be seen that the curve segment JK is a cycloid. Intermediate variable Where:

[0089]

[0090]

[0091] Substitute into the parametric equation of the curve segment JK to obtain the coordinates of point K:

[0092]

[0093] The conjugate curve segment on its male rotor is the curve segment DE, and the parametric equation of the curve segment DE is:

[0094]

[0095] It can be seen that the curve segment DE is also a cycloid. Intermediate variable Where:

[0096]

[0097]

[0098] The small arc segment on the female rotor is the curve segment HI, and the parametric equation of the curve segment HI is:

[0099]

[0100] Where,

[0101]

[0102] The envelope segment of the curve segment HI is the curve segment BC, and the parametric equation of the curve segment BC is:

[0103]

[0104] where θ ∈ (-y, α), the intermediate variable is expressed as:

[0105]

[0106] The parametric equation of the curve segment KI on the male rotor is:

[0107]

[0108] The conjugate curve segment of the curve segment KI on the male rotor, i.e., the curve segment EC, and the parametric equation of the curve segment EC is:

[0109]

[0110] Among them, the design variables of the rotor profile are: center distance A, pin tooth arc radius R, arc HI radius R1, and central angle ε of the curve AD.

[0111] As shown in FIGS. 5(a) and 5(b), it is a schematic diagram of the whole rotary tooth type compressor according to an embodiment of the present invention, showing the positions of the suction port 4 and the discharge port 5, and having the above-mentioned rotor structure.

[0112] As Figure 6 shown, it shows the actual working process of the rotary tooth type compressor according to an embodiment of the present invention. Figure 6 In (a), it is the moment when the intake starts. Subsequently, the gas enters the annular area surrounded by the rotor and the left cylinder hole through the intake port. When the outer convex tooth of the male rotor passes through the intake port for the second time, the gas compression process starts, as Figure 6 shown in (b), and at the same time, the intake process of the next cycle also starts. When reaching Figure 6 in (c), the gas is compressed to the designed maximum pressure. The area S1 surrounded by the female rotor curve and the cylinder has been connected to the discharge port. At this time, the compressed gas is in the area S2 surrounded by the two rotors and the cylinder. As the rotors continue to rotate, the compressed gas will be connected to the discharge port and start to discharge.

[0113] Figure 7 It shows the detailed discharge process. Due to the reasonable rotor profile design of the embodiment of the present invention, the two rotors start to mesh at the intersection of the two cylinder holes, as Figure 7 shown in (b), that is, the meshing line extends to the intersection of the two cylinder holes (the position shown in Figure 1 ), thereby completely isolating the intake process from the discharge process and avoiding reverse leakage of the gas. Finally, the discharge process is completed at the position shown in Figure 6 in (d). As the two rotors rotate, the above process is repeated.

[0114] Next, through Figure 4The rotor profile design parameters shown determine the positions of the suction port and the discharge port. As Figure 6 shown in (a) of it, at the suction start point, in order to ensure no intake loss, when point D on the male rotor reaches the edge of the intake port, it is required that point K on the female rotor reaches the intersection of the two cylinder holes, so that in the subsequent rotation, all the gas enters the annular area enclosed by the male rotor and the cylinder. At the same time, in order to ensure the intake volume, it is desired to compress the gas of the previous cycle before the intake starts, which requires that the central angle corresponding to the intake port cannot be greater than ε. When the central angle corresponding to the intake port is exactly equal to ε, the start of intake corresponds to the start of compressing the gas of the previous cycle. According to the above, the position of the intake port can be determined:

[0115]

[0116] Among them,

[0117]

[0118] The discharge port curve of the present invention is composed of four circular arc curves, such as Figure 4 the closed curve PTSN shown.

[0119] Among them, the curve PN is the meshing line of point D on the male rotor and the curve KJ of the female rotor, and point P coincides with the intersection of the two cylinder holes. As the rotor rotates, when reaching Figure 6 the discharge end point shown in (d) of it, point D on the male rotor meshes with point J on the female rotor at point N, and all the gas has been discharged through the discharge port.

[0120] The parametric equation of the curve PN is:

[0121]

[0122] The curve NS is a trace line of the curve GJ of the female rotor during rotation, and its parametric equation is:

[0123]

[0124] The parametric equations of the curves PT and TS on the discharge port are respectively:

[0125]

[0126]

[0127] For the discharge port curve, the design variable is the central angle σ corresponding to the circular arc NS.

[0128] In the embodiment of the present invention, the rotor profile of the rotary tooth compressor is composed of an arc and its envelope line, point meshing cycloid, pin tooth arc, etc. Its specific shape can be flexibly adjusted by changing the center distance A, the radius R of the pin tooth arc, the radius R1 of the arc HI, and the magnitude of the central angle ε of the curve segment AD. And by precisely designing the positions of the intake port and the exhaust port and coordinating with the rotation of the rotor, the intake, compression, and exhaust processes can proceed smoothly.

[0129] The following gives the design process of a rotary tooth compressor of the present invention in combination with specific parameters:

[0130] As Figure 4 shown, take the center distance A between the two rotors as 60 mm, the radius R of the pin tooth arc as 0.1A = 6 mm, the radius R1 of the small arc as 0.1R = 0.6 mm, the central angle ε as 1 / 18π, and the central angle σ as 1 / 16π.

[0131] Using the following formula

[0132]

[0133] the parameter α = 1.3694 can be determined. Using the following formula

[0134]

[0135] the parameter γ = 0.2218 can be determined, and then all the profile equations of the two rotors can be determined.

[0136] Using the following formula

[0137]

[0138] the parameter ι = 0.4735 can be determined, and the curve equations of each exhaust port can be jointly determined with the parameter σ.

[0139] Using the following formula

[0140]

[0141] the parameter μ = 0.5571 can be determined, and the position of the intake port can be determined.

[0142] In the embodiment of the present invention, the internal compression process of the rotary tooth compressor can be realized by the meshing rotation of the designed male rotor 1 and female rotor 2 in cooperation with the cylinder bore. The rotary tooth compressor of the present invention has a very long intake time and internal compression time, so that the gas can be compressed to a very small volume before being discharged, and a very high exhaust pressure can be achieved, greatly increasing the pressure ratio. And due to the reasonable profile design, the generation of internal leakage channels during the compression process is avoided, improving the compression efficiency. In summary, the rotary tooth compressor of the embodiment of the present invention can be applied to the compressor field under high pressure ratio conditions in the future.

[0143] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A rotary tooth type compressor, characterized in that, It includes a male rotor (1) and a female rotor (2) that mesh with each other. The male rotor (1) has an outer convex profile, and the female rotor (2) has an inner concave profile. The male rotor (1) and the female rotor (2) are arranged inside a cylinder (3). The cylinder (3) has two intersecting circular cylinder bores that respectively accommodate the male rotor (1) and the female rotor (2). An intake port (4) is radially provided on the cylinder (3), and an exhaust port (5) is axially provided on the cylinder (3). The intake port (4) and the exhaust port (5) communicate with the circular cylinder bores. The cross-section of the outer convex profile of the male rotor (1) consists of an arc portion and an outer convex portion connected to the arc portion. The cross-section of the inner concave profile of the female rotor (2) consists of an arc portion and an inner concave portion connected to the arc portion. The outer convex portion is composed of sequentially connected curve segments CB, BA, AD, and DE. The inner concave portion is composed of sequentially connected curve segments IH, HG, GJ, and JK. The curve segments BA, AD, and point D correspond to the curve segments HG, GJ, and JK and conform to the analytical envelope relationship. The curve segments IH, KI, and point K correspond to the curve segments CB, EC, and DE and conform to the analytical envelope relationship; The parametric equation of the curve segment AD is: The curve segment GJ is the conjugate curve segment of the curve segment AD, and the parametric equation of the curve segment GJ is: Wherein, is the central angle of the curve segment AD; The coordinates of point D are (( r p1 +R )) cosε , ( r p1 +R )) sinε ); The parametric equation of the curve segment JK is: In the formula, is an intermediate variable, ; In the formula, A is the center of the male rotor (1) O m and the center of the female rotor (2) O f the distance between; The curve segment BA is a pin tooth arc with a radius of R , and the curve segment IH is an arc with a radius of R 1. The parametric equation of the curve segment BA is: Wherein, In the formula, the pitch circle radii of the male rotor (1) and the female rotor (2) are respectively r p1 and r p2 ; The curve segment HG is the conjugate curve segment of the curve segment BA, and the parametric equation of the curve segment HG is: 。 2. The rotary tooth type compressor according to claim 1, wherein, Substitute into the parametric equation of the curve segment JK to obtain the coordinates of point K. The parametric equation of the coordinates of point K is as follows: 。 3. The rotary tooth type compressor according to claim 2, characterized in that, The parametric equation of the curve segment DE is: In the formula, is an intermediate variable, , where: 。 4. The rotary tooth type compressor according to claim 3, characterized in that, The parametric equation of the curve segment IH is: Wherein, 。 5. The rotary tooth type compressor according to claim 4, wherein, The curve segment CB is the envelope segment of the curve segment IH, and the parametric equation of the curve segment CB is: Among them, , the intermediate variable is expressed as: 。 6. The rotary tooth type compressor according to claim 5, characterized in that, The parametric equation of the curve segment KI is: The curve segment EC is the conjugate curve segment of the curve segment KI, and the parametric equation of the curve segment EC is: 。 7. The rotary tooth type compressor according to claim 6, characterized in that, The position of the intake port (4) is solved by the following formula: Wherein, is the angle of the upper edge point of the aspiration orifice deviating from the x-axis; is the angle of point P on the meshing line deviating from the x-axis, and the solution expression is as follows: The exhaust port (5) is composed of four arc curves of curve segments PN, NS, ST, and TP, wherein: The parametric equation of the curve segment PN is: The curve segment NS is a trajectory line of the curve segment GJ during rotation, and the parametric equation is: The parametric equations of the curve segments TP and ST are respectively: 。

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