Cycloidal speed reducer and wear detection method

Abstract

The cycloid speed reducer comprises a motor, and the motor is in power connection with a speed reducer. The motor comprises a motor main shaft, and the output end of the motor main shaft is of an eccentric shaft structure. The speed reducer comprises a speed reducer shell and a cycloidal gear arranged in the speed reducer shell, the cycloidal gear is in power connection with the power output end of the speed reducer, a torque sensor is arranged at the end of the speed reducer shell, and the cycloidal speed reducer abrasion detection method comprises the steps that S1, the no-load resistance torque T0 of a motor spindle is obtained; s2, the torque TT of the output end of the power unit is obtained; calculating the friction coefficient mu between the sliding bearing and the cycloidal gear; s3, the abrasion condition of the main shaft bearing and the cycloidal gear is judged according to the data characteristics of the friction coefficient mu, and early warning is given out for the abnormal abrasion condition. According to the cycloidal gear speed reducer, the sliding bearing simple in structure is used, the cycloidal gear is made of powder metallurgy materials, the bearing fault rate is reduced, maintenance is easy, the lubricating performance of the cycloidal gear can be improved, and part abrasion is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of cycloid reducers, and in particular to a cycloid reducer and a wear detection method. Background Art

[0002] The cycloid reducer is a special type of transmission device that uses the principle of planetary transmission and cycloid pinion meshing. The cycloid reducer transmission device can be divided into three parts: input part, reduction part, and output part.

[0003] The existing cycloidal pinwheel reducer uses a needle roller bearing for transmission between the eccentric wheel and the cycloidal wheel, which is prone to failure under high-speed conditions, has a complex structure, and is difficult to maintain; the existing cycloidal pinwheel reducer mostly uses materials such as bearing steel for the cycloidal wheel, which may cause lubrication failure between the cycloidal wheel and the bearing under high-speed conditions, resulting in high wear of parts and a short lifespan; 3. The existing cycloidal pinwheel reducer lacks corresponding wear detection devices, making it difficult to issue an early warning when abnormal wear occurs. Summary of the Invention

[0004] The purpose of the invention is to provide a cycloid reducer and a wear detection method to solve the problems raised in the above background technology.

[0005] To achieve the above objectives, the invention provides the following technical solutions:

[0006] A cycloid reducer comprises a motor, wherein the motor is dynamically connected to the reducer;

[0007] The motor comprises a motor main shaft, and the output end of the motor main shaft is an eccentric shaft structure;

[0008] The reducer includes a reducer housing and a cycloid wheel arranged in the reducer housing, the cycloid wheel is power-connected to the power output end of the reducer, the cycloid wheel is plugged into the eccentric shaft section of the motor main shaft, and a sliding bearing is provided between the cycloid wheel and the motor main shaft;

[0009] A torque sensor is provided at the end of the reducer housing.

[0010] As a further solution of the invention: the motor is provided with a motor controller, one end of the reducer housing is provided with an end cover, and the torque sensor is provided on the end cover.

[0011] As a further solution of the invention: a main shaft bearing for supporting the main shaft of the motor is provided in the reducer housing, and a rubber-coated wheel is wrapped outside the reducer housing.

[0012] As a further solution of the invention: the power output end of the reducer is the reducer housing, and the reducer housing is connected to the cycloid wheel through a pinion pin.

[0013] As a further aspect of the invention: the sliding bearing is a laminated structure, and the sliding bearing at least includes a surface layer, an intermediate layer, and a substrate layer. The surface layer is made of modified polytetrafluoroethylene, the intermediate layer is made of spherical bronze powder material, and the substrate layer is made of cold-rolled steel sheet.

[0014] As a further aspect of the invention: the material of the cycloid gear is copper infiltrated steel powder metallurgy. Iron powder and / or iron alloy powder, as well as graphite powder and carbon are pre-mixed and pressed into the shape of a cycloid gear blank. During sintering, copper-based material is infiltrated into the connected pores to form a blank, and then it is processed into a finished cycloid gear.

[0015] A method for detecting wear of a cycloid speed reducer includes the following steps:

[0016] S1. Obtain the parameters under the control state of the motor 1 and calculate the no-load resistance torque T0 of the motor spindle under no-load;

[0017] S2. Under the load state, collect the torque T at the output end of the power unit in real time through a torque sensor T ; calculate the friction torque T between the sliding bearing and the cycloid gear f ; and calculate the friction coefficient μ between the sliding bearing and the cycloid gear in real time according to the friction torque T between the sliding bearing and the cycloid gear f ;

[0018] S3. Analyze the data of the friction coefficient μ collected in real time. The motor controller judges the wear condition of the main shaft bearing and the cycloid gear according to the data characteristics of the friction coefficient μ, and issues a warning for abnormal wear conditions.

[0019] As a further aspect of the invention: in S1, under the no-load working condition, run the motor 1, and after stabilization, read the no-load input voltage U0 and current I0, as well as the input speed n0 of the motor 1 at this time, and calculate the no-load resistance torque T0 of the main shaft of the power unit under no-load. The calculation formula of T0 is as follows:

[0020]

[0021] P I0 = U0I0

[0022] In the above formula, P I0 represents the input power under no-load, and n represents the input speed of the main shaft at this moment.

[0023] As a further aspect of the invention: in S2, under the load working condition, read the input voltage U and current I in real time, as well as the input speed n of the motor at this time, and collect the torque T at the output end of the power unit in real time T , calculate the friction torque T between the sliding bearing and the cycloid gear f . T fThe calculation formula is as follows:

[0024]

[0025]

[0026] P I = UI

[0027] In the above formula, T I represents the input torque under load, i represents the reduction ratio of the reducer, and P I represents the input power under load;

[0028] The friction coefficient μ between the sliding bearing and the cycloid gear is calculated in real time. The calculation formula of μ is as follows:

[0029]

[0030] In the above formula, F represents the normal pressure between the cycloid gear and the main shaft bearing, and R represents the distance from the contact point to the rotation center, that is, the rotation radius.

[0031] As a further solution of the invention: The data characteristics, corresponding problems and treatment methods of the friction coefficient μ between the sliding bearing and the cycloid gear are as follows:

[0032] When the μ data gradually decreases and then stabilizes, it belongs to the normal situation, and only regular maintenance is required according to the requirements;

[0033] When the μ data suddenly increases, there is adhesive wear or scuffing, and the surface material of the parts may be transferred, and the parts need to be replaced;

[0034] When the μ data shows abnormal values, such as negative values or exceeding 1, there are large assembly errors or assembly mistakes in the equipment, resulting in abnormal detection data, and it needs to be disassembled and reassembled;

[0035] When the μ data shows irregular fluctuations, there is abrasive wear, and the surface of the parts may be damaged. Maintenance or replacement of parts needs to be carried out according to the situation.

[0036] When the μ data shows periodic fluctuations, there may be eccentric wear or fatigue wear, which will cause cracks or spalling of the parts in the long term, and it is necessary to disassemble and check in time, and reassemble or replace the parts according to the situation.

[0037] Compared with the prior art, the beneficial effects of the invention are:

[0038] 1. The cycloid gear reducer of the present application uses a sliding bearing with a simple structure, and the cycloid gear uses a powder metallurgy material, which reduces the bearing failure rate, is easy to maintain, can increase the lubrication performance of the cycloid gear, and reduces part wear;

[0039] 2. The wear detection method of the present application can issue a warning for abnormal wear during the operation of the power unit, prompting technicians to take corresponding measures to reduce the failure rate and maintenance cost. Description of the Drawings

[0040] Figure 1 It is a schematic diagram of the side of the reducer shaft in this embodiment;

[0041] Figure 2 It is a sectional view of the reducer in this embodiment;

[0042] Figure 3 It is a flowchart of the wear method in this embodiment.

[0043] In the figure: 1 - motor, 2 - motor controller, 3 - motor main shaft, 4 - main shaft bearing, 5 - cycloid gear, 6 - pin tooth pin, 7 - reducer housing, 8 - end cover, 9 - torque sensor, 10 - sliding bearing, 11 - rubber-coated wheel. Detailed Embodiment

[0044] Next, the technical solutions in the embodiments of the invention will be clearly and completely described in conjunction with the drawings in the embodiments of the invention. Obviously, the described embodiments are only a part of the embodiments of the invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the invention without creative efforts shall fall within the scope of protection of the invention.

[0045] Please refer to Figure 1 , in the embodiment of the invention, a cycloid reducer includes a motor 1, and the motor 1 is power-connected to a reducer;

[0046] The motor 1 includes a motor main shaft 3. The motor 1 is provided with a motor controller 2 to control the operation of the motor 1 through the motor controller 2. At the same time, the working device of the motor 1 is monitored through the motor controller 2. The output end of the motor main shaft 3 is an eccentric shaft structure, and the output power of the motor 1 is transmitted to the reducer through the motor main shaft 3.

[0047] The reducer includes a reducer housing 7 and a cycloid gear 5 arranged in the reducer housing 7. In this embodiment, the reducer housing 7 is power-connected to the cycloid gear 5 through a pin tooth pin 6. The cycloid gear 5 is power-connected to the power output end of the reducer. The cycloid gear 5 is inserted into the eccentric shaft section of the motor main shaft 3. A sliding bearing 10 is arranged between the cycloid gear 5 and the motor main shaft 3. At the same time, a main shaft bearing 4 for supporting the motor main shaft 3 is arranged in the reducer housing 7, and the rotation of the motor main shaft 3 is made more stable through the main shaft bearing 4;

[0048] One end of the reducer housing 7 is provided with an end cover 8, and a torque sensor 9 is arranged at the end of the reducer housing 7. The torque sensor 9 is arranged on the end cover 8.

[0049] The power output end of the speed reducer is the speed reducer housing 7, and the outside of the speed reducer housing 7 is wrapped with a rubber-coated wheel 11, and the rubber-coated wheel 11 is driven to rotate by the speed reducer housing 7.

[0050] The sliding bearing has strong load-bearing capacity and simple structure, and has a low failure rate under high-speed operating conditions. The surface layer of the sliding bearing material contacts the cycloid gear, and the surface layer has a small friction coefficient, which can reduce the wear of the cycloid gear. In this embodiment, the sliding bearing 10 is a layered structure, and the sliding bearing 10 at least includes a surface layer, an intermediate layer, and a base material layer. The surface layer is made of modified polytetrafluoroethylene, the intermediate layer is made of spherical bronze powder material, and the base material layer is made of cold-rolled steel plate.

[0051] The cycloid gear 5 is made of powder metallurgy. The cycloid gear material is copper-infiltrated steel powder metallurgy. Iron powder and / or ferroalloy powder, as well as graphite powder (carbon) are pre-mixed powder, and then the iron powder or iron-based powder is pressed into the shape of the cycloid gear blank, and the copper-based material is infiltrated into the connected pores during sintering to make a blank part, and then processed into a finished cycloid gear. Since the copper-infiltrated steel powder metallurgy material contains graphite powder, it can achieve self-lubrication function during operation, with a small friction coefficient, which can reduce the wear of the sliding bearing.

[0052] A method for detecting the wear of a cycloid speed reducer includes the following steps:

[0053] S1. Obtain the parameters under the control state of the motor 1 and calculate the no-load resistance torque T0 of the motor spindle 3 under no-load;

[0054] In this embodiment, due to the compact internal structure of the power unit, it is impossible to add sensor equipment, so the spindle torque is calculated by collecting motor data. Under no-load conditions, the power unit is operated, and after stabilization, the no-load input voltage U0, current I0, and the motor input speed n0 at this time are read. Calculate the no-load resistance torque T0 of the power unit spindle under no-load. The calculation formula of T0 is as follows:

[0055]

[0056] P I0 =U0I0

[0057] In the above formula, P I0 represents the input power under no-load, and n represents the spindle input speed at this moment.

[0058] S2. Under the load state, obtain the torque T output by the power unit in real time through the torque sensor 9 T . Calculate the frictional torque T f between the sliding bearing and the cycloid gear; and calculate the friction coefficient μ f between the sliding bearing and the cycloid gear in real time according to the frictional torque T

[0059] Install a strain torque sensor on the end face of the end seal cover of the power unit. Under load conditions, read the input voltage U and current I in real time, as well as the motor input speed n at this time. Collect the torque T at the output end of the power unit in real time T Calculate the frictional torque T between the sliding bearing and the cycloid gear f T f The calculation formula is as follows:

[0060]

[0061] P I = UI

[0062] In the above formula, T I represents the input torque under load, i represents the reduction ratio of the reducer, and P I represents the input power under load

[0063] Calculate the friction coefficient μ between the sliding bearing and the cycloid gear in real time. The calculation formula of μ is as follows:

[0064]

[0065] In the above formula, F represents the normal pressure between the cycloid gear and the main shaft bearing, and R represents the distance from the contact point to the center of rotation, that is, the radius of rotation

[0066] S3. Analyze the friction coefficient μ data collected in real time. The motor controller judges the wear condition of the main shaft bearing and the cycloid gear according to the data characteristics of the friction coefficient μ, and issues a warning for abnormal wear

[0067] The data characteristics of the friction coefficient μ, the corresponding problems and treatment methods are as follows:

[0068] (1) The μ data gradually decreases and then stabilizes, which is a normal situation. Just perform regular maintenance as required

[0069] (2) The μ data suddenly increases, there is adhesive wear or scuffing, and the surface material of the parts may be transferred. Replace the parts

[0070] (3) Abnormal values appear in the μ data. If negative values or values exceeding 1 appear, there are large assembly errors or assembly mistakes in the equipment, resulting in abnormal detection data. Disassemble and reassemble

[0071] (4) The μ data fluctuates irregularly, there is abrasive wear, and the surface of the parts may be damaged. Perform maintenance or replace parts according to the situation

[0072] (5) The μ data shows periodic fluctuations, there may be uneven wear or fatigue wear, and cracks or spalling of the parts will occur in the long term. Disassemble and check in time, reassemble or replace parts according to the situation

[0073] For those skilled in the art, it is obvious that the invention is not limited to the details of the above exemplary embodiments, and the invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the invention. Any reference signs in the claims should not be construed as limiting the claims involved.

[0074] In addition, it should be understood that although this specification is described in terms of embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A cycloid speed reducer, comprising a motor (1), characterized in that, The motor (1) is power-connected to a speed reducer; The motor (1) includes a motor main shaft (3), and the output end of the motor main shaft (3) is an eccentric shaft structure; The speed reducer includes a speed reducer housing (7) and a cycloid gear (5) disposed within the speed reducer housing (7). The cycloid gear (5) is power-connected to the power output end of the speed reducer. The cycloid gear (5) is inserted into the eccentric shaft section of the motor main shaft (3), and a sliding bearing (10) is provided between the cycloid gear (5) and the motor main shaft (3); A torque sensor (9) is provided at the end of the speed reducer housing (7).

2. The cycloid speed reducer according to claim 1, characterized in that, The motor (1) is provided with a motor controller (2). One end of the speed reducer housing (7) is provided with an end cover (8), and the torque sensor (9) is disposed on the end cover (8).

3. A cycloidal speed reducer according to claim 1, characterized in that, A main shaft bearing (4) for supporting the motor main shaft (3) is provided within the speed reducer housing (7), and the outside of the speed reducer housing (7) is wrapped with a rubber-coated wheel (11).

4. A cycloidal speed reducer and a wear detection method according to claim 1, characterized in that, The power output end of the speed reducer is the speed reducer housing (7), and the speed reducer housing (7) is power-connected to the cycloid gear (5) through a pin tooth pin (6).

5. A cycloid speed reducer according to claim 1, characterized in that, The sliding bearing (10) is a layered structure. The sliding bearing (10) at least includes a surface layer, an intermediate layer, and a base material layer. The surface layer is made of modified polytetrafluoroethylene, the intermediate layer is made of spherical bronze powder material, and the base material layer is made of cold-rolled steel sheet.

6. A cycloid speed reducer according to claim 1, characterized in that, The material of the cycloid gear (5) is copper-infiltrated steel powder metallurgy. Iron powder and / or iron alloy powder, as well as graphite powder carbon, are pre-mixed and pressed into the shape of a cycloid gear blank. During sintering, a copper-based material is infiltrated into the connected pores to form a blank part, and then it is processed into a finished cycloid gear.

7. A method for detecting wear of a cycloid reducer, characterized in that, It includes the following steps: S1. Obtain the parameters under the control state of the motor (1) and calculate the no-load resistance torque T0 of the motor main shaft (3) under no-load; S2. Under the load condition, the torque T at the output end of the power unit is collected in real time through the torque sensor (9). T Calculate the frictional torque T between the sliding bearing and the cycloid gear. f And calculate the friction coefficient μ between the sliding bearing and the cycloid gear in real time according to the frictional torque T between the sliding bearing and the cycloid gear. f ​ S3. Analyze the data of the friction coefficient μ collected in real time. The motor controller judges the wear conditions of the main shaft bearing and the cycloid gear according to the data characteristics of the friction coefficient μ, and issues a warning for abnormal wear conditions.

8. A cycloid speed reducer wear detection method according to claim 7, characterized in that, In S1, under no-load working conditions, run the motor 1. After stabilization, read the no-load input voltage U0 and current I0, and the input speed n0 of the motor 1 at this time, and calculate the no-load resistance torque T0 of the power unit main shaft under no-load. The calculation formula of T0 is as follows: P I0 = U0I0 In the above formula, P I0 represents the input power at no load, and n represents the input speed of the spindle at this moment.

9. A cycloid speed reducer wear detection method according to claim 7, characterized in that In S2, under the load condition, the input voltage U, current I, and the input speed n of the motor at this time are read in real time, and the torque T at the output end of the power unit is collected in real time. T , and calculate the frictional torque T between the sliding bearing and the cycloid gear f . T f The calculation formula is as follows: P I = UI In the above formula, T I represents the input torque at load, i represents the reduction ratio of the reducer, and P I represents the input power at load; Calculate the friction coefficient μ between the sliding bearing and the cycloid gear in real time. The calculation formula of μ is as follows: In the above formula, F represents the normal pressure between the cycloid gear and the main shaft bearing, and R represents the distance from the contact point to the rotation center, that is, the rotation radius.

10. A cycloid speed reducer wear detection method according to claim 7, characterized in that, The data characteristics, corresponding problems and treatment methods of the friction coefficient μ between the sliding bearing and the cycloid gear are as follows: When the μ data gradually decreases and then tends to be stable, it belongs to the normal situation, and only regular maintenance is required according to the requirements; When the μ data suddenly increases, there is adhesive wear or scuffing, and the surface material of the parts may be transferred, and the parts need to be replaced; When the μ data shows abnormal values, such as negative values or exceeding 1, there are large assembly errors or assembly mistakes in the equipment, resulting in abnormal detection data, and it needs to be disassembled and reassembled; When the μ data shows irregular fluctuations and there is abrasive wear, damage may occur on the surface of the part. Maintenance or replacement of the part should be carried out according to the situation. When the μ data shows periodic fluctuations, there may be uneven wear or fatigue wear. In the long term, cracks or spalling may occur on the part. It is necessary to disassemble and inspect it in time, and reassemble or replace the part according to the situation.

Images