Hypocycloidal pin gear speed reducer assembly, speed reducer and application

Abstract

The invention relates to a hypocycloidal pin gear speed reducer assembly, a speed reducer and application. The speed reducer comprises an input shaft system, a first output shaft system and a second output shaft system; the number ratio of rotors to stators of the input shaft system is N: (N + 1), the section contours of the rotors and the stators are equidistant lines of a pair of conjugated hypocycloids, the rotors do planetary motion in the stators, the rotors rotate around the centers of the rotors and revolve around the centers of the stators at the same time, and the speed ratio of rotation to revolution is (N + 1): N. An input shaft rotates at the revolution speed of the rotors. Output shafts in the first output shaft system and the second output shaft system are connected through splines on the shafts and rotate according to the difference between the rotation speed and the revolution speed of a rotor, the purpose of speed reduction is achieved, and the speed reduction ratio is N: 1; and the rotor and the stator are made of steel with the hardness of over HRC58. The hypocycloid pin wheel speed reducer has the advantages of being high in transmission efficiency, stable in operation and long in service life, the outer diameter of the hypocycloid pin wheel speed reducer is smaller than the allowable maximum outer diameter of an oil well shaft, the hypocycloid pin wheel speed reducer can be suitable for screw pump oil extraction, and the technical problem that a pin wheel speed reducer cannot be suitable for an oil well all the time is solved.

Description

Technical Field

[0001] The present disclosure relates to a reducer used in the technical field of screw pump oil production, and in particular to a hypocycloid pinwheel reducer used in a submersible screw pump oil production system. Background Art

[0002] The screw pump oil production process is a commonly used artificial lifting method in oil field exploitation. It uses a screw pump to lift crude oil from underground oil wells to the ground. Screw pump oil production is divided into ground-driven screw pump oil production system and submersible screw pump oil production system. The submersible screw pump oil production system eliminates the sucker rod, which is more energy-saving and safer than the ground-driven screw pump. The speed range of the submersible screw pump is usually between 100 and 500 rpm, and the speed of the motor is usually higher than that of the submersible screw pump, with 1400 and 2900 rpm being common. Based on the objective need that the motor speed does not match the pump speed, the submersible screw pump oil production system must reduce the speed and increase the torque through the reducer.

[0003] At present, the reducers that can be used in the submersible screw pump oil production system generally use planetary gear reduction, see "Submersible Screw Pump Oil Production Technology and System Design", Metallurgical Industry Press, edited by Wang Shijie and Li Qin. However, the use of planetary gear reducers currently has the following technical problems: the root cutting of the involute causes the minimum number of gear teeth to be greater than 17. After displacement, the minimum number of teeth can be 14. Even so, the module of the involute teeth is limited by the wellbore diameter and can only be 3.25. The tooth thickness is only 5.1mm, which makes the gear teeth very thin, with limited load-bearing capacity and easy to fail. Since the reducer is prone to failure, it limits the promotion and application of submersible screw pump oil production systems using planetary gear reduction in oil fields.

[0004] As shown in Chinese patent document CN113236716B, under this scheme, the designer uses a short hypocycloid as the tooth profile curve, and the minimum number of teeth can be 2, and the commonly used number of teeth is 5-9. This makes it possible for the gear tooth thickness to be more than 8mm even if the number of teeth is 9 when the maximum outer diameter of the reducer is 90mm, and the gear tooth thickness can reach more than 15mm when the number of teeth is 6, greatly improving the bearing capacity and service life of the gear teeth. However, the scheme of CN113236716B also has technical problems that need to be solved: the rotor and the stator are sliding friction, the relative sliding distance of the gear teeth is long, the friction heat is large, and the mechanical efficiency is low, making it difficult to achieve long-term reliable operation in oil wells.

[0005] Although the existing cycloidal pinwheel reducer can theoretically solve the above-mentioned technical problems, the epicycloid and constant angular speed ratio structure it adopts causes its diameter to be too large (the current epicycloidal pinwheel reducer has a minimum diameter of 167 mm, while the conventional oil well has a diameter of 139 mm, and the downhole tool diameter is generally required to be less than 114 mm), and it cannot be lowered into the wellbore, so it has no practical application possibility.

[0006] In summary, the prior art lacks a reducer that can be applied to screw pump oil production to enable the submersible screw pump to maintain long-term efficient and stable operation. Summary of the invention

[0007] In order to solve the technical problems existing in the background technology, the present disclosure proposes an hypocycloidal pinwheel reducer assembly, a reducer and an application. Through the content disclosed by the technical scheme, a short-width hypocycloidal pinwheel reducer with high transmission efficiency, smooth operation, reliable operation, long service life, compact structure and small radial size can be obtained. When the required deceleration is relatively large, multiple reducers can be connected in series by connecting them end to end to form a multi-stage deceleration.

[0008] First, in a first aspect of the present disclosure, a hypocycloid pinwheel reducer assembly is provided, including an input shaft system, wherein the input shaft system has an input shaft, a stator and a rotor, and the uniqueness thereof is that:

[0009] The input shaft system also includes a floating plate; the floating plate has a circular hole in the center and four circular grooves on the edge of the floating plate;

[0010] The rotor is assembled in the stator with a fixed eccentricity, and the cross-sectional profiles of the rotor and the stator are a pair of equidistant lines of conjugated hypocycloids. The rotor performs planetary motion in the stator according to the meshing principle of hypocycloids, so that the rotor rotates around its own center, that is, around the center of the eccentric shaft section on the input shaft, and simultaneously revolves around the center of the stator;

[0011] When the input shaft rotates, the eccentric shaft section on the input shaft starts to revolve, driving the second input shaft sliding bearing to revolve, driving the rotor to revolve, and the speed of the input shaft is equal to the revolving speed of the rotor;

[0012] The number of rotor heads is N, the number of stator heads is N+1, N is a natural number greater than or equal to 2, and the reduction ratio of the reducer is N:1;

[0013] The rotor is connected to the eccentric shaft section on the input shaft through the second input shaft sliding bearing;

[0014] The short pin-tooth pin and the long pin-tooth pin cooperate with the pin-tooth sleeve to be mounted on the rotor to realize the rolling of the rotor in the stator, and the long pin-tooth pin and the pin-tooth sleeve matched therewith are inserted into the floating disk;

[0015] The rotor and the stator are made of steel with a hardness of HRC58 or above, preferably stainless steel.

[0016] Furthermore, the input shaft system also includes a counterweight, which is arranged on the input shaft to achieve dynamic balance and offset the vibration, noise and wear caused by the rotation of the eccentric mass when the rotor performs planetary motion in the stator.

[0017] Furthermore, the value of the eccentricity is equal to the rolling radius R constituting the stator hypocycloid multiplied by the amplitude coefficient K.

[0018] The hypocycloid pinwheel reducer assembly also includes a first output shaft system:

[0019] The first output shaft system includes a first output shaft sliding bearing and a first output shaft equipped with a first tapered roller bearing and a second tapered roller bearing;

[0020] The planetary motion output of the rotor is achieved through the cooperation of the rotor, the short pin-tooth pin, the long pin-tooth pin, the stator, the floating plate, the output shaft pin-tooth pin and the first output shaft;

[0021] The center line of the first output shaft coincides with the center line of the stator, that is, the revolution center of the rotor;

[0022] The input shaft is inserted into the center hole of the first output shaft through the circular hole in the center of the floating plate;

[0023] The output shaft pin and the matching pin gear sleeve are inserted into the first output shaft, and the pin gear pin and the matching pin gear sleeve can move the first output shaft;

[0024] The long needle tooth pin and the needle tooth sleeve matched therewith pass through two symmetrical circular grooves on the floating plate, and the output shaft needle tooth pin and the needle tooth sleeve matched therewith pass through another two symmetrical circular grooves on the floating plate;

[0025] When the rotor rotates, the long pin-tooth pin and the pin-tooth sleeve matched therewith move the floating plate, and then the floating plate moves the pin-tooth pin and the pin-tooth sleeve matched therewith, and then the pin-tooth pin of the output shaft moves the first output shaft to rotate around the center of the stator;

[0026] The rotor's rotation is opposite to its revolution direction;

[0027] The ratio of the rotor's rotation angular velocity to its revolution angular velocity is equal to the ratio of the number of stator heads to the number of rotor heads; the rotor's rotation angular velocity is the rotation speed of the rotor around its own center; since the rotation and revolution directions of the rotor are opposite, the rotation speed of the first output shaft is equal to the difference between the rotor's rotation speed (N+1)ω and the revolution speed Nω, which is ω, and the rotation speed of the input shaft is equal to the revolution speed of the rotor, so the reduction ratio of the reducer is N.

[0028] Furthermore, the reducer assembly also includes a second output shaft system:

[0029] The second output shaft system includes a second output shaft, a first cylindrical roller bearing, a second output shaft sliding bearing, a thrust ball bearing and a second cylindrical roller bearing; the first cylindrical roller bearing, the second cylindrical roller bearing and the thrust ball bearing are all arranged on the second output shaft, so that after the second output shaft is subjected to an axial force of external interference, the axial force can be transferred to the outside of the reducer;

[0030] The distance between the center of the eccentric shaft section on the input shaft and the common center of the first output shaft and the second output shaft is equal to the eccentricity of the rotor in the stator; the first output shaft and the second output shaft are connected by a spline between the two shafts, and the rotation speeds are equal, that is, the output speed is the difference between the rotor rotation speed and the revolution speed.

[0031] Furthermore, there is an axial gap between the first output shaft and the second output shaft to ensure that the axial force does not affect the first output shaft and the preceding mechanical structure connected thereto.

[0032] The second aspect of the present disclosure provides a hypocycloid pinwheel reducer, including a first reducer housing, which is unique in that:

[0033] Apply the aforementioned hypocycloid pinwheel reducer assembly which only includes the input shaft system and the first output shaft system;

[0034] The input shaft is connected to the first reducer housing through a first input shaft sliding bearing;

[0035] The stator is fixed in the first reducer housing through the stator locating pins. When the reducer is running, the stator and the first reducer housing remain stationary.

[0036] Furthermore, the hypocycloid pinwheel reducer includes a second reducer housing in addition to the first reducer housing, and the hypocycloid pinwheel reducer assembly includes an input shaft system, a first output shaft system, and a second output shaft system. There may be an axial gap between the first output shaft and the second output shaft of the second output shaft system, or there may not be one, but it is obvious that the solution with the axial gap is better.

[0037] The stator is fixed in the first reducer housing through a stator locating pin;

[0038] The first reducer housing and the second reducer housing are fixed by housing locating pins;

[0039] The input shaft is connected to the first reducer housing through a first input shaft sliding bearing;

[0040] The second reducer housing is provided with a first spacer ring and a second spacer ring, which are used to position the first tapered roller bearing and the second tapered roller bearing, and to transmit the pressure of the nut to the inner ring of the bearing to prevent the bearing from being displaced in the axial direction;

[0041] The second reducer housing is provided with a supporting thread.

[0042] The third aspect of the present disclosure provides a screw pump oil production system, that is, the application of the aforementioned hypocycloid pinwheel reducer in the field of submersible screw pump oil production.

[0043] The hypocycloid pinwheel reducer including an input shaft system, a first output shaft system and a second output shaft system is applied to oil production by a submersible screw pump;

[0044] The input shaft of the input shaft system is connected to the motor shaft of the screw pump or the transmission shaft of the protector;

[0045] The second output shaft is connected to a reducer protector, the reducer protector is connected to a coupling, and the coupling is connected to a screw pump.

[0046] The following uses Chinese patent document CN113236716B as a comparison object to illustrate that at least one of the above technical solutions adopted in one or more embodiments of this specification can achieve the following beneficial effects:

[0047] First, the thickness of the stator is significantly reduced, the force transmission performance is improved, and the mechanical efficiency is increased. The formula for thickness calculation is: stator thickness = (0.1-0.2) × stator center circle radius Rz, Rz is Fig.13 shown.

[0048] Secondly, the rotor has been transformed from a single part into an assembly, consisting of a rotor, a short needle tooth pin, a long needle tooth pin and a needle tooth sleeve, thereby converting the sliding friction between the reducer rotor and the stator into rolling friction. The needle tooth sleeve can roll around the short needle tooth pin, reducing frictional heat and improving force.

[0049] Again, this type of reducer uses a floating plate as an output mechanism. There is a circular hole in the center of the floating plate, and the input shaft is inserted into the center hole of the first output shaft through this hole; there are 4 circular grooves on the edge of the floating plate, and the long needle tooth pin and the needle tooth sleeve matched therewith pass through two symmetrical circular grooves, and the output shaft needle tooth pin and the needle tooth sleeve matched therewith pass through the other two symmetrical circular grooves. When the rotor rotates, the long needle tooth pin and the needle tooth sleeve matched therewith move the floating plate, and then the floating plate moves the output shaft needle tooth pin and the needle tooth sleeve matched therewith. Since the output shaft needle tooth pin and the needle tooth sleeve matched therewith are inserted into the first output shaft at the same time, the output shaft needle tooth pin and the needle tooth sleeve matched therewith can move the first output shaft. The structure of the floating plate (15) is as follows: Fig.24 , while reducing the weight of the reducer, it also reduces vibration.

[0050] In addition, the right end of the input shaft extends into the first output shaft and is supported by a bearing, which changes the cantilever beam structure of the input shaft mounted on the rotor in the previous scheme to a simply supported beam, thereby optimizing the force on the input shaft and making the rotor run more smoothly.

[0051] In addition, the second output shaft can provide axial force support, thereby preventing the axial force from being transmitted to the rotor and also reducing friction.

[0052] In addition to the above points, the reducer proposed in the present disclosure does not require the processing of screws, so it does not require a screw machine tool, and can be produced by an ordinary CNC milling machine. Moreover, compared with the stator of the screw reducer made of rubber, the rotor and stator in this solution can be made of steel, and the service life of the reducer is greatly extended.

[0053] In summary, the publicly provided solution combines a needle wheel reducer and an inner cycloid reducer to form a short-amplitude inner cycloid needle wheel reducer. The outer diameter of this inner cycloid needle wheel reducer can be smaller than the maximum outer diameter allowed by the oil well bore, and can be used in screw pump oil production. This solves the technical problem that needle wheel reducers have not been suitable for screw pump oil production, and also has the advantages of high transmission efficiency, smooth operation, reliable operation and long service life.

[0054] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

[0055] Further features and aspects of the present disclosure will become apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The drawings herein are incorporated into the specification and constitute a part of the specification. These drawings illustrate embodiments consistent with the present disclosure and are used to illustrate the technical solutions of the present disclosure together with the specification.

[0057] Figure 1 It is a schematic diagram of the structure of the stator described in the present invention.

[0058] Figure 2 It is a schematic structural diagram of the rotor assembly disclosed in the present invention.

[0059] Figure 3 It is a schematic structural diagram of the input shaft and the counterweight thereon described in the present invention.

[0060] Figure 4 This is a structural diagram of the stator and rotor assembly described in the present disclosure.

[0061] Figure 5 A cross-sectional shape diagram of a rotor and a stator when the ratio of the number of rotor heads to the number of stators is 6:7 in a specific embodiment provided by the present disclosure.

[0062] Figure 6 This is an exploded view of the input shaft system described in the present disclosure.

[0063] Figure 7It is a schematic diagram of the structure of the input shaft system disclosed in the present invention.

[0064] Figure 8 This is an exploded view of the first output shaft system disclosed in the present invention.

[0065] Fig. 9 It is a schematic diagram of the structure of the first output shaft system disclosed in the present invention.

[0066] Fig.10 It is an exploded view of the second output shaft system disclosed in the present invention.

[0067] Fig.11 It is a schematic diagram of the structure of the second output shaft system disclosed in the present invention.

[0068] Fig.12 It is an exploded view of the connection between the input shaft and the first output shaft described in the present invention.

[0069] Fig.13 1 is a cross-sectional profile diagram of the stator described in the present disclosure.

[0070] Fig.14 It is an assembly exploded view of the reducer disclosed in the present invention.

[0071] Fig.15 This is a structural diagram of the reducer assembly disclosed in the present invention.

[0072] Fig.16 It is a schematic diagram of the structure of the stator locating pin and the casing locating pin of the reducer disclosed in the present invention.

[0073] Fig.17 It is a schematic structural diagram of the first output shaft of the present invention.

[0074] Fig.18 It is a schematic structural diagram of the first output shaft sliding bearing disclosed in the present invention.

[0075] Fig.19 It is a schematic structural diagram of the second output shaft sliding bearing disclosed in the present invention.

[0076] Fig. 20 It is a schematic structural diagram of the short needle tooth pin disclosed in the present invention.

[0077] Fig.21 It is a schematic structural diagram of the long needle tooth pin disclosed in the present invention.

[0078] Fig. 22 It is a schematic diagram of the matching structure of the short needle tooth pin and the needle tooth sleeve.

[0079] Fig.23 It is a schematic diagram of the matching structure of the long needle tooth pin and the needle tooth sleeve.

[0080] Fig.24It is a schematic diagram of the structure of the floating disk disclosed in the present invention.

[0081] In the figure, 1-first reducer housing, 2-input shaft, 3-counterweight, 4-first input shaft sliding bearing, 5-second input shaft sliding bearing, 6-rotor, 7-stator, 8-short pin, 9-long pin, 10-pin sleeve, 11-stator positioning pin, 12-stator positioning hole, 13-casing positioning pin, 14-casing positioning hole, 15-floating plate, 16-output shaft pin, 17-first output shaft, 18-first output shaft sliding shaft Bearing, 19-first spacer ring, 20-first tapered roller bearing, 21-second spacer ring, 22-second tapered roller bearing, 23-hexagonal thin nut, 24-second output shaft, 25-support thread, 26-first sleeve ring, 27-first cylindrical roller bearing, 28-second sleeve ring, 29-thrust ball bearing, 30-second output shaft sliding bearing, 31-hexagonal fine pitch nut, 32-second cylindrical roller bearing, 33-second reducer housing. DETAILED DESCRIPTION

[0082] Various exemplary embodiments, features and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0083] In addition, in order to better illustrate the present disclosure, numerous specific details are given in the following specific embodiments. It should be understood by those skilled in the art that the present disclosure can also be implemented without certain specific details. In some examples, methods and means well known to those skilled in the art are not described in detail in order to highlight the main purpose of the present disclosure.

[0084] The deceleration principle of this reducer is as follows:

[0085] The cross-sectional profile of the rotor 6 and the stator 7 is a pair of equidistant lines of the conjugate hypocycloid. The rotor 6 performs planetary motion in the stator 7. The rotor 6 rotates around its own center at a speed of ω1 while revolving around the center of the stator 7 at a speed of ω2. The number of rotors 6 is N, and the number of stators 7 is N+1. ω1:ω2=(N+1):N. By using this feature, a reducer is made. The input speed is the revolution of the rotor 6, and the output speed is the difference between the rotation and revolution of the rotor 6, so as to achieve the purpose of deceleration. When the required deceleration is relatively large, multiple reducers can be connected in series by connecting them end to end to form a multi-stage deceleration. For example, two reducers are connected in series to obtain a reduction ratio of 36, and three reducers are connected in series to obtain a reduction ratio of 216.

[0086] In summary, the optimal structure of this type of hypocycloid pinwheel reducer includes three major shaft system components, namely the input shaft system, the first output shaft system and the second output shaft system.

[0087] The present invention will be further described below in conjunction with the accompanying drawings:

[0088] Input shaft system Figure 6 , Figure 7 As shown, it includes an input shaft 2, a first input shaft sliding bearing 4, a counterweight 3, a second input shaft sliding bearing 5, a rotor 6, a stator 7, a short needle tooth pin 8, a long needle tooth pin 9, a needle tooth sleeve 10, and a floating plate 15.

[0089] The rotor is connected to the eccentric shaft section on the input shaft through the second input shaft sliding bearing; the short pin and the long pin are mounted on the rotor in conjunction with the pin gear sleeve to achieve the rolling of the rotor in the stator, and the long pin and the pin gear sleeve are inserted into the floating plate; when the rotor performs planetary motion in the stator, the counterweight on the input shaft is used to achieve dynamic balance, offset the vibration, noise and wear caused by the rotation of the eccentric mass, and extend the service life of the machine.

[0090] like Fig.24 As shown, there is a circular hole in the center of the floating plate 15, and the input shaft is inserted into the center hole of the first output shaft through this hole; there are 4 circular grooves on the edge of the floating plate, and the long needle tooth pin and the needle tooth sleeve matched therewith pass through two symmetrical circular grooves, and the needle tooth pin 16 and the needle tooth sleeve matched therewith pass through the other two symmetrical circular grooves. When the rotor rotates, the long needle tooth pin and the needle tooth sleeve matched therewith move the floating plate 15, and then the floating plate 15 moves the needle tooth pin 16 and the needle tooth sleeve matched therewith 10. Since the needle tooth pin 16 and the needle tooth sleeve matched therewith 10 are inserted into the first output shaft 17 at the same time, the needle tooth pin 16 and the needle tooth sleeve matched therewith can move the first output shaft.

[0091] The number of rotor heads is N, the number of stator heads is N+1, N is a natural number greater than or equal to 2, and the reduction ratio of the reducer is N:1. By changing the number of rotor heads N, reducers with different reduction ratios can be obtained. Figure 5 It is an assembly schematic diagram in which the ratio of the number of rotors 6 to stators 7 is 6:7, and the reduction ratio is 6:1.

[0092] The stator is fixed in the first reducer housing 1 by the stator locating pin 11. During operation, the stator and the first reducer housing and the second reducer housing 33 remain stationary. The rotor is assembled in the stator with a certain eccentricity. The cross-sectional profiles of the rotor and the stator are a pair of equidistant lines of conjugated hypocycloids. The rotor performs planetary motion in the stator according to the meshing principle of hypocycloids, so that the rotor rotates around its own center, that is, around the center of the eccentric shaft section on the input shaft, and revolves around the center of the stator at the same time, achieving the purpose of deceleration.

[0093] The second reducer housing 33 is provided with a first spacer ring 19 and a second spacer ring 21, which are used to position the first tapered roller bearing 20 and the second tapered roller bearing 22, and can also transmit the pressure of the nut to the inner ring of the bearing to ensure stable pressure to prevent unnecessary axial displacement of the bearing; the second reducer housing 33 is provided with a support thread 25.

[0094] The rotor is assembled in the stator with a certain eccentricity, and the value of the eccentricity is equal to the rolling radius R constituting the stator inner cycloid multiplied by the amplitude coefficient K; when the input shaft rotates, the eccentric shaft section on the input shaft starts to revolve, driving the second input shaft sliding bearing 5 to start revolving, driving the rotor to start revolving, and the rotation speed of the input shaft is equal to the revolution speed of the rotor.

[0095] The first output shaft is Figure 8 , Fig. 9 As shown, it includes a first output shaft 17, a first output shaft sliding bearing 18, an output shaft needle gear pin 16, a needle gear sleeve 10, a first tapered roller bearing 20 and a first tapered roller bearing 22, and a nut 23; a pair of tapered roller bearings installed on the first output shaft can reduce friction and heat during operation and ensure precise alignment between the shaft and the bearing seat.

[0096] The planetary motion output of the rotor is completed through the cooperation of the rotor, the short pin pin, the long pin pin, the pin sleeve, the stator, the floating plate, the output shaft pin and the first output shaft. The rotor 6 is connected to the eccentric shaft section on the input shaft 2 through the second input shaft sliding bearing 5. When the input shaft 2 rotates, the eccentric shaft section on the input shaft 2 starts to revolve, driving the second input shaft sliding bearing 5 to revolve, and then driving the rotor 6 to revolve. The speed of the input shaft 2 is equal to the revolution speed of the rotor 6.

[0097] The rotor 6 is assembled in the stator 7 with a certain eccentricity, and performs planetary motion around the center of the stator 7 according to the meshing principle of the hypocycloid. The meshing motion of the rotor 6 and the stator 7 is reflected in the cross-sectional profile as the guide circle of the rotor 6 performing pure rolling in the guide circle of the stator 7. This pure rolling is equivalent to two motions of the rotor 6, one is the revolution of the rotor 6 around the center of the stator 7, and the other is the rotation of the rotor 6 around its own center. The rotation of the rotor 6 is opposite to the revolution direction, and the ratio of the angular velocity of the rotation of the rotor 6 to the revolution is inversely proportional to the number of heads of the rotor and the stator. The rotation speed of the first output shaft 17 is equal to the difference between the rotation speed of the rotor and the revolution speed. The first output shaft 17 and the second output shaft 24 are connected by a spline between the two shafts, and the rotation speed is equal, that is, the output speed is the difference between the rotation speed of the rotor 6 and the revolution speed.

[0098] The second output shaft is Fig.10 , Fig.11As shown, it includes a second output shaft 24, a first cylindrical roller bearing 27, a second output shaft sliding bearing 30, a thrust ball bearing 29, a pair of nuts 31, and a second cylindrical roller bearing 32; when the second output shaft 24 is subjected to an axial force of external interference, the axial force is transferred to the second reducer housing 33 through the two cylindrical roller bearings on the shaft, a pair of nuts, the thrust ball bearing, the first ring 26 and the second ring 28 on the second reducer housing 33, and the supporting thread 25, and finally the axial force is transferred to the fixed machinery outside the reducer. At the same time, due to the axial gap between the first output shaft 17 and the second output shaft 24, it is ensured that the axial force will not affect the first output shaft and the front mechanical structure connected thereto.

[0099] The distance between the center of the eccentric shaft section on the input shaft and the common center of the first output shaft 17 and the second output shaft 24 is equal to the eccentricity of the rotor in the stator; the first output shaft 17 and the second output shaft 24 are connected by a spline between the two shafts, and the rotation speeds are equal, that is, the output speed is the difference between the rotor rotation speed and the revolution speed.

[0100] The first reducer housing and the second reducer housing are fixed by the housing locating pin 13; the input shaft is connected to the first reducer housing through the first input shaft sliding bearing 4; the stator 7 is fixed to the first reducer housing through the stator locating pin 12; during operation, the stator and the first reducer housing and the second reducer housing are stationary. A counterweight 3 is installed on the input shaft 2 to achieve dynamic balance when the rotor 6 performs planetary motion in the stator 7, to offset the vibration, noise and wear caused by the rotation of the rotor 6, and to extend the mechanical life.

[0101] The first output shaft 17 is provided with a first spacer ring 19, a second spacer ring 21 and a hexagonal thin nut 23 for positioning the first tapered roller bearing 20 and the second tapered roller bearing 22. The pressure from the nut to the inner ring of the bearing can be transmitted to ensure a stable pressure to prevent unnecessary axial displacement of the bearing.

[0102] When the second output shaft 24 is subjected to an axial force caused by external interference, the axial force is transferred to the second reducer housing 33 through the first cylindrical roller bearing 27 and the first cylindrical roller bearing 32, a pair of hexagonal fine-pitch nuts 31, the thrust ball bearing 29 and the first ring 26, the second ring 28 and the supporting thread 25 on the second reducer housing 33, and then the axial force is transferred to the fixed machinery outside the reducer. At the same time, due to the axial gap between the first output shaft and the second output shaft, it is ensured that the axial force will not affect the first output shaft and the front mechanical structure connected to it.

[0103] The input shaft 2 is provided with a first input shaft sliding bearing 4 and a second input shaft sliding bearing 5, and the first output shaft 17 and the second output shaft 24 are provided with an output shaft sliding bearing 30 and a plurality of rolling bearings, including a first tapered roller bearing 20, a second tapered roller bearing 22, a first cylindrical roller bearing 27 and a second cylindrical roller bearing 32. These bearings can ensure that the input shaft 2 and the first output shaft 17 and the second output shaft 24 rotate around the center of the reducer.

[0104] The rotor 6 is connected to the eccentric shaft section on the input shaft 2 through the second input shaft sliding bearing 5. When the input shaft 2 rotates, the eccentric shaft section on the input shaft starts to revolve, driving the second input shaft sliding bearing 5 to revolve accordingly, and then driving the rotor 6 to revolve. The rotation speed of the input shaft 2 is equal to the orbital speed of the rotor 6.

[0105] The rotor 6 is assembled in the stator 7 with a certain eccentricity, and performs planetary motion around the center of the stator 7 according to the meshing principle of the hypocycloid. The meshing motion of the rotor 6 and the stator 7 is reflected in the cross-sectional profile as the guide circle of the rotor 6 performing pure rolling in the guide circle of the stator 7. The pure rolling is equivalent to two motions of the rotor 6, one is the revolution of the rotor 6 around the center of the stator 7, and the other is the rotation of the rotor 6 around its own center. The rotation of the rotor 6 is opposite to the revolution direction. The ratio of the angular velocity of the rotation of the rotor 6 to the revolution is inversely proportional to the number of heads of the rotor and the stator. The rotation speed of the first output shaft 17 is equal to the difference between the rotation speed and the revolution speed of the rotor 6.

[0106] The first output shaft 17 and the second output shaft 24 are connected by a spline between the two shafts, and the rotation speeds are equal, that is, the output speed is the difference between the rotation speed and the revolution speed of the rotor 6.

[0107] The counterweight 3 installed on the input shaft 2 can achieve dynamic balance when the rotor 6 performs planetary motion in the stator 7, offset the vibration, noise and wear caused by the rotation of the rotor 6, and extend the mechanical life.

[0108] The first output shaft 17 is provided with a first tapered roller bearing 20 and a second tapered roller bearing 22, which can reduce friction and heat generation during operation and ensure accurate alignment between the shaft and the bearing seat.

[0109] Compared with the previous reducer for oil wells based on the hypocycloid meshing principle, the reducer provided in the present disclosure significantly reduces the thickness of the stator 7, improves the force transmission performance, and improves the mechanical efficiency; compared with the previous patent, the rotor is changed from a single part to an assembly, consisting of a rotor, a short needle tooth pin, a long needle tooth pin, and a needle tooth sleeve. The advantage of this is that the sliding friction between the reducer rotor and the stator of the previous design is converted into rolling friction. The needle tooth sleeve can roll around the short needle tooth pin, which greatly reduces frictional heat and improves force.

[0110] The working process of this reducer is as follows:

[0111] The power of an electric motor, an internal combustion engine or other high-speed rotating engine is transmitted to the reducer through the input shaft, and the input shaft starts to rotate, and at the same time, the eccentric shaft section on the input shaft starts to revolve, and at the same time, the sliding bearing of the second input shaft starts to revolve, and at the same time, the rotor starts to revolve, and the speed of the input shaft is equal to the speed of the rotor's revolution. The rotor is assembled in the stator with a certain eccentricity, and performs planetary motion around the center of the stator according to the meshing principle of the hypocycloid. The first output shaft and the second output shaft are connected by a spline between the two shafts, and the speed is equal, that is, the output speed is the difference between the rotor's rotation speed and the revolution speed, thereby achieving the purpose of deceleration.

[0112] When the required deceleration is relatively large, multiple reducers are connected in series end to end to form a multi-stage reduction.

[0113] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A hypocycloid pinwheel reducer assembly, comprising an input shaft system, wherein the input shaft system has an input shaft, a stator and a rotor, and is characterized in that: The input shaft system also includes a floating plate; the floating plate has a circular hole in the center and four circular grooves on the edge of the floating plate; The rotor is assembled in the stator with a fixed eccentricity, and the cross-sectional profiles of the rotor and the stator are a pair of equidistant lines of conjugated hypocycloids. The rotor performs planetary motion in the stator according to the meshing principle of hypocycloids, so that the rotor rotates around its own center, that is, around the center of the eccentric shaft section on the input shaft, and simultaneously revolves around the center of the stator; When the input shaft rotates, the eccentric shaft section on the input shaft starts to revolve, driving the second input shaft sliding bearing to revolve, driving the rotor to revolve, and the speed of the input shaft is equal to the revolving speed of the rotor; The number of rotor heads is N, the number of stator heads is N+1, N is a natural number greater than or equal to 2, and the reduction ratio of the reducer is N:1; The rotor is connected to the eccentric shaft section on the input shaft through the second input shaft sliding bearing; The short needle tooth pin and the long needle tooth pin cooperate with the needle tooth sleeve to be mounted on the rotor to realize the rolling of the rotor in the stator, and the long needle tooth pin and the needle tooth sleeve matched therewith are inserted into the floating disk; The rotor and the stator are both made of steel, with a hardness of HRC58 or above.

2. The hypocycloid pinwheel reducer assembly according to claim 1, characterized in that: The input shaft system also includes a counterweight, which is arranged on the input shaft to achieve dynamic balance and offset the vibration, noise and wear caused by the rotation of the eccentric mass when the rotor performs planetary motion in the stator.

3. A hypocycloid pinwheel reducer assembly according to claim 1 or 2, characterized in that: The value of the eccentricity is equal to the rolling radius R constituting the stator inner cycloid multiplied by the amplitude coefficient K.

4. The hypocycloid pinwheel reducer assembly according to claim 3, characterized in that: The assembly includes a first output shaft system; The first output shaft system includes a first output shaft sliding bearing and a first output shaft equipped with a first tapered roller bearing and a second tapered roller bearing; The planetary motion output of the rotor is achieved through the cooperation of the rotor, the short pin-tooth pin, the long pin-tooth pin, the stator, the floating plate, the output shaft pin-tooth pin and the first output shaft; The center line of the first output shaft coincides with the center line of the stator, that is, the revolution center of the rotor; The input shaft is inserted into the center hole of the first output shaft through the circular hole in the center of the floating plate; The output shaft pin and the matching pin gear sleeve are inserted into the first output shaft, and the pin gear pin and the matching pin gear sleeve can move the first output shaft; The long needle tooth pin and the needle tooth sleeve matched therewith pass through two symmetrical circular grooves on the floating plate, and the output shaft needle tooth pin and the needle tooth sleeve matched therewith pass through another two symmetrical circular grooves on the floating plate; When the rotor rotates, the long pin-tooth pin and the pin-tooth sleeve matched therewith move the floating plate, and then the floating plate moves the pin-tooth pin and the pin-tooth sleeve matched therewith, and then the pin-tooth pin of the output shaft moves the first output shaft to rotate around the center of the stator; The rotor's rotation is opposite to its revolution direction; The ratio of the rotor's rotational angular velocity to its revolution angular velocity is equal to the ratio of the number of stator heads to the number of rotor heads; the rotor's rotational angular velocity is the speed at which the rotor rotates around its own center; The rotation speed of the first output shaft is equal to the difference between the rotation speed of the rotor and the revolution speed; the rotation speed of the input shaft is equal to the revolution speed of the rotor.

5. The hypocycloid pinwheel reducer assembly according to claim 4, characterized in that: The reducer assembly also includes a second output shaft system; The second output shaft system includes a second output shaft, a first cylindrical roller bearing, a second output shaft sliding bearing, a thrust ball bearing and a second cylindrical roller bearing; the first cylindrical roller bearing, the second cylindrical roller bearing and the thrust ball bearing are all arranged on the second output shaft, so that after the second output shaft is subjected to an axial force of external interference, the axial force can be transferred to the outside of the reducer; The distance between the center of the eccentric shaft section on the input shaft and the common center of the first output shaft and the second output shaft is equal to the eccentricity of the rotor in the stator; the first output shaft and the second output shaft are connected by a spline between the two shafts, and the rotation speeds are equal, that is, the output speed is the difference between the rotor rotation speed and the revolution speed.

6. The hypocycloid pinwheel reducer assembly according to claim 5, characterized in that: An axial gap is provided between the first output shaft and the second output shaft to ensure that the axial force does not affect the first output shaft and the preceding mechanical structure connected thereto.

7. A hypocycloid pinwheel reducer, comprising a first reducer housing, characterized in that: Using the hypocycloid pinwheel reducer assembly described in claim 4; The input shaft is connected to the first reducer housing through a first input shaft sliding bearing; The stator is fixed in the first reducer housing through the stator locating pins. When the reducer is running, the stator and the first reducer housing remain stationary.

8. A hypocycloid pinwheel reducer, comprising a first reducer housing and a second reducer housing, characterized in that: Any one of the hypocycloid pinwheel reducer assemblies described in claim 5 or 6 is used; The stator is fixed in the first reducer housing through a stator locating pin; The first reducer housing and the second reducer housing are fixed by housing locating pins; The input shaft is connected to the first reducer housing through a first input shaft sliding bearing; The second reducer housing is provided with a first spacer ring and a second spacer ring, which are used to position the first tapered roller bearing and the second tapered roller bearing, and to transmit the pressure of the nut to the inner ring of the bearing to prevent the bearing from being displaced in the axial direction; The second reducer housing is provided with a supporting thread.

9. A screw pump oil production system, characterized in that: The hypocycloid pinwheel reducer according to claim 8 is used; The input shaft of the input shaft system is connected to the motor shaft of the screw pump or the transmission shaft of the protector; The second output shaft is connected to a reducer protector, the reducer protector is connected to a coupling, and the coupling is connected to a screw pump.

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