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China Custom 51: 1 Corner Low Backlash Belt Conveyor Gearbox planetary gears gear ratio

Product Description

Product Description

The 51: 1 corner low backlash belt conveyor gearbox is a new micro precision cycloid and circular gear reducer developed and manufactured by WEITENSTAN together with German and ZheJiang technicians for many years.

High precision miniature cycloidal gearbox has the characteristics of smaller, ultra-thin, lightweight and high rigidity, anti-overload and high torque. With good deceleration performance, smooth operation and accurate positioning can be achieved. Integrated design, can be directly connected with the motor, to achieve high precision, high rigidity, high durability and other advantages. It is designed for high speed ratio, high geometric accuracy, low motion loss, large torque capacity and high stiffness applications. The compact design (minimum OD ≈40mm, currently the world’s smallest precision cycloidal pin-wheel reducer) allows it to be installed in limited Spaces.

Detailed Photos

 

Product Advantage

51: 1 corner low backlash belt conveyor gearbox advantages:

 

1, fine precision cycloidal structure

Ultra flat shape is achieved through differential reduction mechanism and thin cross roller bearing, contributing to the compact size of the equipment. The combination of small size and unmatched superior parameters achieves the best combination of performance, price and size (high cost performance).

 

2. Excellent accuracy (transmission loss ≤1 arcmin)

Through the complex meshing of precision cycloid gear and high precision roller pin, higher transmission accuracy is achieved while maintaining small size and high speed ratio.

 

3, high rigidity

Increase the mesh rate to disperse the load, so the rigidity is high.

 

4. High overload capacity

It maintains trouble-free operation under abnormally low noise and vibration conditions while ensuring excellent overturning and torsional stiffness parameters. Integrated axial radial cross roller bearings, high load capacity and overload capacity of the reducer, can ensure users to provide a variety of temperature range of applications.

 

5, the motor installation is simple

Electromechanical integration design, can be directly connected with the motor, any brand of motor can be installed directly, without adding any device.

 

6. Maintenance free

Seal grease to achieve maintenance free. No refueling, no mounting direction restrictions.

 

7, stable performance

The manufacturing process of high wear-resistant materials and high precision parts has been certified by ISO9000 quality system, which guarantees the reliable operation of the reducer.

 

Product Classification

 

WF Series
High Precision Miniature Reducer

WF series is a high precision micro cycloidal reducer with flange, which has a wide range of applications. This series of reducers includes precise reduction mechanisms and radial – axial roller bearings. The unique design allows load to act directly on the output flange or housing without additional bearings. WF series reducer is characterized by module design, can be installed through the flange motor and reducer, belongs to the motor directly connected reducer.

WFH Series
High Precision Miniature Reducer

WFH series is a hollow form of high precision miniature cycloidal reducer, wire, compressed air pipeline, drive shaft can be through the hollow shaft, non-motor direct connection type reducer. The WFH series is fully sealed, full of grease and includes precise deceleration mechanism and radial – axial roller bearings. The unique design allows load to be acted directly on the output flange or housing without additional bearings.

 

Product Parameters

Size reduction ratio Rated output moment Allowable torque of start and stop Instantaneous allowable moment Rated input speed Maximum input speed Tilt stiffness Torsional stiffness No-load starting torque Transmission accuracy Error accuracy Moment of inertia Weight
  Axis rotation Shell rotation Nm Nm Nm rpm rpm Nm/arcmin Nm/arcmin Nm arcmin arcmin kg-m² kg
WFH07 21 20 15 30 45 3000 6000 6 1.1 0.12 P1≤±1           P2≤±3 P1≤±1           P2≤±3 0.52 0.42
41 40 0.11 0.47
WFH17 21 20 50 100 150 3000 6000 28 6 0.21 P1≤±1           P2≤±3 P1≤±1           P2≤±3 0.88 0.85
41 40 0.18 0.72
61 60 0.14 0.69
WFH25 21 20 110 220 330 3000 5500 131 24 0.47 P1≤±1           P2≤±3 P1≤±1           P2≤±3 6.12 2
31 30 0.41 5.67
41 40 0.38 4.9
51 50 0.35 4.56
81 80 0.31 4.25
WFH32 25 24 190 380 570 3000 4500 240 35 1.15 P1≤±1           P2≤±3 P1≤±1           P2≤±3 11 4.2
31 30 1.1 10.8
51 50 0.77 9.35
81 80 0.74 8.32
101 100 0.6 7.7
WFH40 25 24 320 640 960 3000 4000 377 50 1.35 P1≤±1           P2≤±3 P1≤±1           P2≤±3 13.2 6.6
31 30 1.32 12.96
51 50 0.92 11.22
81 80 0.81 9.84
121 120 0.72 8.4

Company Profile

 

Q: Speed reducer grease replacement time
A: When sealing appropriate amount of grease and running reducer, the standard replacement time is 20000 hours according to the aging condition of the grease. In addition, when the grease is stained or used in the surrounding temperature condition (above 40ºC), please check the aging and fouling of the grease, and specify the replacement time.

Q: Delivery time
A: Fubao has 2000+ production base, daily output of 1000+ units, standard models within 7 days of delivery.

Q: Reducer selection
A: Fubao provides professional product selection guidance, with higher product matching degree, higher cost performance and higher utilization rate.

Q: Application range of reducer
A: Fubao has a professional research and development team, complete category design, can match any stepping motor, servo motor, more accurate matching.

 

Shipping Cost:

Estimated freight per unit.



To be negotiated
Application: Motor, Machinery, Agricultural Machinery, Automatic Equipment
Hardness: Hardened Tooth Surface
Installation: Vertical Type
Customization:
Available

|

Customized Request

helical gearbox

Cyclone Gearbox Vs Involute Gearbox

Whether you’re using a cycloidal gearbox or an involute gearbox for your application, there are a few things you should know. This article will highlight some of those things, including: cycloidal gearbox vs involute gearbox, weight, compressive force, precision, and torque density.

Compressive force

Several studies have been carried out to analyze the static characteristics of gears. In this article, the authors investigate the structural and kinematic principles of a cycloidal gearbox. The cycloidal gearbox is a gearbox that uses an eccentric bearing inside a rotating frame. It has no common pinion-gear pair, and is therefore ideal for a high reduction ratio.
The purpose of this paper is to investigate the stress distribution on a cycloidal disc. Various gear profiles are investigated in order to study the load distribution and dynamic effects.
Cycloidal gearboxes are subject to compression and backlash, which require the use of proper ratios for the bearing rate and the TSA. The paper also focuses on the kinematic principles of the reducer. In addition, the authors use standard analysis techniques for the shaft/gear and the cycloidal disc.
The authors previously worked on a rigid body dynamic simulation of a cycloidal reducer. The analysis used a trochoidal profile on the cycloidal disc periphery. The trochoidal profile is obtained from a manufacturing drawing and takes into account the tolerances.
The mesh density in the cycloidal disc captures the exact geometry of the parts. It provides accurate contact stresses.
The cycloidal disc consists of nine lobes, which move by one lobe per rotation of the drive shaft. However, when the disc is rotated around the pins, the cycloidal disc does not move around the center of gravity. Therefore, the cycloidal disc shares torque load with five outer rollers.
A low reduction ratio in a cycloidal gearbox results in a higher induced stress in the cycloidal disc. This is due to the bigger hole designed to reduce the material inside the disc.

Torque density

Several types of magnetic gearboxes have been studied. Some magnetic gearboxes have a higher torque density than others, but they are still not able to compete with the mechanical gearboxes.
A new high torque density cycloidal magnetic gearbox using Halbach rotors has been developed and is being tested. The design was validated by building a CPCyMG prototype. The results showed that the simulated slip torque was comparable to the experimental slip torque. The peak torque measured was a p3 = 14 spatial harmonic, and it corresponds to the active region torque density of 261.4 N*m/L.
This cycloidal gearbox also has a high gear ratio. It has been tested to achieve a peak torque of 147.8 Nm, which is more than double the torque density of the traditional cycloidal gearbox. The design incorporates a ferromagnetic back-support that provides mechanical fabrication support.
This cycloidal gearbox also shows how a small diameter can achieve a high torque density. It is designed with an axial length of 50mm. The radial deflection forces are not serious at this length. The design uses a small air gap to reduce the radial deflection forces, but it is not the only design option.
The trade-off design also has a high volumetric torque density. It has a smaller air gap and a higher mass torque density. It is feasible to make and mechanically strong. The design is also one of the most efficient in its class.
The helical gearing design is a newer technology that brings a higher level of precision to a cycloidal gearbox. It allows a servomotor to handle a heavy load at high cycle rates. It is also useful in applications that require smaller design envelopes.helical gearbox

Weight

Compared to planetary gearboxes, the weight of cycloidal gearboxes is not as significant. However, they do provide some advantages. One of the most significant features is their backlash-free operation, which helps them deliver smooth and precise movement.
In addition, they provide high efficiency, which means that servo motors can run at higher speeds. The best part is that they do not need to be stacked up in order to achieve a high ratio.
Another advantage of cycloidal gearboxes is that they are usually less expensive than planetary gearboxes. This means that they are suitable for the manufacturing industry and robotics. They are also suited for heavy-duty robots that require a robust gearbox.
They also provide a better reduction ratio. Cycloidal gears can achieve reduction ratios from 30:1 to 300:1, which is a huge improvement over planetary gears. However, there are few models available that provide a ratio below 30:1.
Cycloidal gears also offer more resistance to wear, which means that they can last longer than planetary gears. They are also more compact, which helps them achieve high ratios in a smaller space. The design of cycloidal gears also makes them less prone to backlash, which is one of the major shortcomings of planetary gearboxes.
In addition, cycloidal gears can also provide better positioning accuracy. In fact, this is one of the primary reasons for choosing cycloidal gears over planetary gears. This is because the cycloid disc rotates around a bearing independently of the input shaft.
Compared to planetary gearboxes, cycloidal gears are also much shorter. This means that they provide the best positioning accuracy. They are also 50% lighter, meaning that they have a smaller diameter.

Precision

Several experts have studied the cycloidal gearbox in precision reducers. Their research mainly focuses on the mathematical model and the method for precision evaluation of cycloidal gears.
The traditional modification design of cycloidal gears is mainly realized by setting various machining parameters and center position of the grinding wheel. But it has some disadvantages because of unstable meshing accuracy and uncontrollable tooth profile curve shape.
In this study, a new method of modification design of cycloidal gears is proposed. This method is based on the calculation of meshing backlash and pressure angle distribution. It can effectively pre-control the transmission accuracy of cycloid-pin gear. It can also ensure good meshing characteristics.
The proposed method can be applied in the manufacture of rotary vector reducers. It is also applicable in the precision reducer for robots.
The mathematical model for cycloidal gears can be established with the pressure angle a as a dependent variable. It is possible to calculate the pressure angle distribution and the profile pressure angle. It can also be expressed as DL=f(a). It can be applied in the design of precision reducers.
The study also considers the root clearance, the backlash of gear teeth and the profile angle. These factors have a direct effect on the transmission performance of cycloidal gear. It also indicates the higher motion accuracy and the smaller backlash. The modified profile can also reflect the smaller transmission error.
In addition, the proposed method is also based on the calculation of lost motion. It determines the angle of first tooth contacts. This angle is an important factor affecting the modification quality. The transmission error after the second cycloid method is the least.
Finally, a case study on the CZPT RV-35N gear pair is shown to prove the proposed method.helical gearbox

Involute gears vs cycloidal gears

Compared to involute gears, cycloidal gears have a lower noise, less friction, and last longer. However, they are more expensive. Cycloidal gears can be more difficult to manufacture. They may be less suitable for certain applications, including space manipulators and robotic joints.
The most common gear profile is the involute curve of a circle. This curve is formed by the endpoint of an imaginary taut string unwinding from the circle.
Another curve is the epicycloid curve. This curve is formed by the point rigidly attached to the circle rolling over another circle. This curve is difficult to produce and is much more expensive to produce than the involute curve.
The cycloid curve of a circle is also an example of the multi-cursor. This curve is generated by the locus of the point on the circle’s circumference.
The cycloid curve has the same diameter as the involute curve, but is tangentially curving along the circle’s diameter. This curve is also classified as ordinary. It has several other functions. The FE method was used to analyze the strain state of cycloidal speed reducers.
There are many other curves, but the involute curve is the most widely used gear profile. The involute curve of a circle is a spiraling curve traced by the endpoint of an imaginary tautstring.
Involute gears are a lot like a set of Lego blocks. They are a lot of fun to play with. They also have a lot of advantages. For example, they can handle center sifts better than cycloidal gears. They are also much easier to manufacture, so the cost of involute teeth is lower. However, they are obsolete.
Cycloidal gears are also more difficult to manufacture than involute gears. They have a convex surface, which leads to more wear. They also have a simpler shape than involute gears. They also have less teeth. They are used in rotary motions, such as in the rotors of screw compressors.
China Custom 51: 1 Corner Low Backlash Belt Conveyor Gearbox   planetary gears gear ratioChina Custom 51: 1 Corner Low Backlash Belt Conveyor Gearbox   planetary gears gear ratio
editor by CX 2023-05-09

China Custom Drive Gear – 3222314238 – CZPT Gearbox for Drilling Machine cycloidal drive efficiency

Product Description

Rexroth Planetary Gearbox

DRIVE GEAR – – Atlas Copco

Gft60W3b86-06 CZPT China GFT110W3B129 Planetary Gearbox Reducer GFT80W3B99 GFT110W3B96
 Gft17/Gft24/Gft26/Gft34/Gft36/Gft40/Gft50  
322
atlas copco original drive gear.

2312904 DRIVE UNIT · HOLDER · CLAMP · ROOF PLATE · CONTROL MODULE · SEAL 
– – – – DRIVE UNIT – – – – DRIVENHET 31 GFT 24 T3 – – – – – HYDRAULIC MOTOR – – – – – HYDRAULMOTOR 33 A6VE 55HZ3 – – – – TRACK CHAIN – – – – LARVBAND – – – TRACK FRAME – – – BANDRAM 37 LEFT – – – – BANDPULLEY – – – – BANDRULLE – – – – LIMBEROLLER – – – – BÄRRULLE – – – – FRONT WHEEL – – – – FRAMHJUL – – – – DRIVE UNIT – – – – DRIVENHET 31 GFT 24 T3 – – – – – HYDRAULIC MOTOR – – – – – HYDRAULMOTOR 33 A6VE 55HZ3

Product Application  Gft110W3b115-06  GFT60W GFT80W GFT110W
Rexroth GFT 110 GFT80 Hydraulic Reducers For Concrete Mixers
Excavators CZPT Final Winch Drive Gearbox GFT 110 GFT80 Reducers
GFT80 GFT160 Reducer Gearbox CZPT Hydraulic Gearbox For Excavators

GFT walking reducer is widely used in rotary drilling rig walking, the main winch, small size, compact structure, large output torque, easy installation, direct connection with the walking tire,

GFT hydrostatic transmission (travel reducer / travel motor) is a gear or chain drive vehicles and other mobile devices ideal drive. In addition, where there is movement, rotation and rotation are applicable. Due to its particularly compact construction, the GFT transmission can also be used where the installation environment is extremely difficult. The use of surface hardened gears and quenched and tempered and surface nitrided gears, coupled with good manufacturing quality, enables the device to have excellent load carrying capacity and operational reliability.
 Brake: Spring loaded, hydraulically released spring pressure in the actuator – Multi-disc – Stop brake. Collectively: multi-chip parking brake. Whenever necessary, even at the project stage, we are always ready to advise you on how to find the most suitable solution for you.

HangZhou Yuan Yi Hydraulic Equipment Co., Ltd. is located in the provincial capital of HangZhou, ZheJiang Province, agents and distribution of foreign CZPT brands Rexroth, Sauer 

Hydraulic control components of the technology-oriented enterprises. Committed to providing customers with high-quality hydraulic control components and hydraulic system design, maintenance, etc.

Surface services. The company has long been CZPT with foreign hydraulic enterprises to maintain close cooperative partnership to ensure that the original products for customers; for customers

To provide rapid response and comprehensive pre-sale, sales, after-sales service; provide reasonable, preferential products. Company’s main products are: import Rexroth

, CZPT CZPT hydraulic piston pumps, motors, gear pumps, reducer assembly and accessories. China-made CZPT brands Xihu (West Lake) Dis. hydraulic professional sales. public

Division customers in the mixing truck, underground scraper, grain combine harvesters, ship machinery, concrete pump truck, coal mining machinery, road rollers,

Paver, port machinery, oilfield machinery, rotary drilling rig and other industries supporting the application.

Package product:

MF21, PV22, MF22, PV23, MF23, and so on, which are widely used in agriculture, forestry, agriculture,

MV23, PV23 + PV23 double piston pump, and motor.

Acting Sales:

Bosch Rexroth: A2F, A6V, A7V, A8V, A11VO, A4VG, A10VSO.

Kawasaki: K3V, K3VG, K5V.

Linde: HPV-02, HPR-02, HMF-02, HMV-02.

SAUER: 90 series, 40 series, 45 series, 20 series, such as assembly and accessories

Companies to undertake professional import hydraulic pump, motor repair, commissioning, and provide free advisory services.

Construction machinery:

Digging machine, paver, road roller, press, paver, drilling machine, bulldozer, heavy CZPT machine, road mixer and so on.

 

Shipping Cost:

Estimated freight per unit.



To be negotiated
Application: Motor
Function: Distribution Power
Layout: Cycloidal
Customization:
Available

|

Customized Request

How to Use a Cyclone Gearbox

Often, a cycloidal gearbox is used in order to achieve a torque transfer from a motor or pump. This type of gearbox is often a common choice as it has a number of advantages over a regular gearbox. Its main advantage is that it is easy to make, which means that it can be incorporated into a variety of applications. However, if you want to use a cycloidal gearbox, there are a few things that you need to know. These include the operation principle, the structure and the dynamic and inertial effects that come with it.helical gearbox

Dynamic and inertial effects

Several studies have been carried out on the static and dynamic properties of cycloidal gears. The study of these effects is beneficial in assisting optimal design of cycloidal speed reducers.
In this paper, the dynamic and inertial effects of a two-stage cycloidal speed reducer have been investigated using the CZPT program package. Moreover, a new model for cycloidal reducers based on non-linear contact dynamics has been developed. The new model aims to predict several operational conditions.
The normal excitation contact force for the cycloid discs of the first and second stage is very similar. However, the total deformation at the contact point is different. This effect is mainly due to the system’s own oscillations. The cycloid discs of the second stage turn around the ring gear roller with a 180deg angle. This angle is a significant contributor to the torque loads. The total excitation force on the cycloid discs of first and second stage is 1848 N and 2068.7 N, respectively.
In order to analyze the contact stress, different gear profiles were investigated. The mesh density was considered as an important design criterion. It was found that a bigger hole reduces the material content of the cycloidal disc and results in more stresses.
Moreover, it is possible to reduce the contact forces in a more efficient manner by changing the geometric parameters. This can be done by mesh refinement along the disc width. The cycloidal disc has the greatest influence on the output results.
The efficiency of a cycloidal drive increases with the increase in load. The efficiency of a cycloidal reducer also depends on the eccentricity of the input shaft and the cycloidal plate. The efficiency curve for small loads is linear. However, for the larger loads, the efficiency curve becomes more non-linear. This is because the stiffness of the cycloid reducer increases as the load increases.

Structure

Despite the fact that it looks like a complicated engineering puzzle, the construction of a cycloidal gearbox is actually quite simple. The key elements are the base, the load plate and the thrust bearing. All these elements work together to create a stable, compact gearbox.
The base is a circular section with several cylindrical pins around its outer edge. The pins are fixed on a fixed ring that holds them in a circular path. The ring serves as a reference circle. The circle’s size is approximately 5mm in diameter.
The load plate is a series of threaded screw holes. These are arranged 15mm away from the center. These are used to anchor external structures. The load plate must be rotated around the X and Y axis.
The thrust bearing is placed on top of the load plate. The bearing is made of an internal diameter of 35mm and an external diameter of 52mm. It is used to allow rotation around the Z axis.
The cycloidal disc is the centerpiece of the cycloidal gearbox. The disc has holes for the pins that drive the output shaft. The holes are larger than those used in output roller pins. The disc also has a reduced eccentricity.
The pins are attached to the cycloidal disc by rolling pins. The pins are made of a material that provides mechanical support for the drive during high-torque situations. The pins have a 9mm external diameter. The disc has a number of lobes and is rotated by one lobe per shaft revolution.
The cycloidal gearbox also has a top cover that helps keep the components together. The cover has a pocket for tools. The top cover also has threads that screw into the casing.helical gearbox

Operation principle

Among many types of gear transmissions, cycloidal gearboxes are used in heavy machinery and multi-axis robots. They are highly effective, compact and capable of high ratios. In addition, they have an overload capability.
Cycloid disks are driven by eccentric shafts that rotate around fixed ring pins. Roller pins of the pin disc engage with holes in the cycloidal disc. These roller pins drive the pin disc and the pin disc transfers the motion to the output shaft.
Unlike conventional gear drives, cycloidal drives have low backlash and high torsional stiffness. They are ideally suited to heavy loads and all drive technologies. The lower mass and compact design of the cycloidal disk also contributes to its high efficiency and positioning accuracy.
The cycloidal disc plays a central role in the gearbox kinematics. It rotates around a fixed ring in a circle. When the disc is pushed against the ring gear, the pins engage with the disc and the roller pins rotate around the pins. This rotating motion generates vibration, which travels through the driven shafts.
Cycloid discs are typically designed with a short cycloid, so that the eccentricity is minimized. This reduces unbalance forces at high speeds. Ideally, the number of lobes on the cycloid is smaller than the number of surrounding pins. This reduces the amount of Hertzian contact stress.
Unlike planetary gears, cycloidal gears have high accuracy and are capable of withstanding shock loads. They also experience low friction and less wear on tooth flanks. They also have higher efficiency and load capacity.
Cycloid gears are generally more difficult to manufacture than involute gears. Cycloid gears are not suitable for stacking gear stages. They require extreme accuracy for manufacturing. However, their smaller size and low backlash, high torsional stiffness, and low vibration make them ideal for use in heavy machines.

Involute gear tooth profile

Almost all gears are manufactured with an involute gear tooth profile. Cycloid gears are also produced with this profile. Compared with involute gears, cycloid gears are stronger and can transmit more power. However, they can also be more difficult to manufacture. This makes them costlier.
The involute gear tooth profile is a smooth curve. It is derived from the involute curve of a circle. A tangent to the base circle is the normal at any point of an involute.
This curve has properties that allow the involute gear teeth to transfer motion in perpendicular direction. It is also the path traced by the end of the string unwrapping from a cylinder.
An involute profile has the advantage of being easy to manufacture. It also allows for smooth meshing despite misalignment of the centre distance. This profile is also preferred over a cycloid tooth profile, but it is not the best in every regard.
Cycloid gear teeth are also made of two curves. Unlike involute teeth, cycloid gear teeth have a consistent radius. Cycloid gears are less likely to produce noise. But they are also more expensive to manufacture.
Involute teeth are easier to manufacture because they have only one curve. Cycloid gears can also be made with a rack type cutter. This makes them cheaper to manufacture. However, they require an expert design. They can also be manufactured with a gear shaper that includes a pinion cutter.
The tooth profiles that satisfy the law of gear-tooth action are sometimes called conjugate profiles. The involute profile is the most common of these. It allows for constant torque transmission.helical gearbox

Backlash

Typically, cycloidal drives provide a high ratio of transmission with no backlash. This is because the cycloid disc is driven by an eccentric shaft. During rotation, the cycloid disc rotates around a fixed ring. This ring also rotates independently of the center of gravity.
The cycloid disc is typically shortened to reduce the eccentricity. This helps to minimize the unbalance forces that may occur at high speeds. The cycloid also offers a larger gear ratio than traditional gears. This provides a better positional accuracy.
Cycloid drives also have a high torsional stiffness. This provides greater torsional resilience and shock load capabilities. This is important for a number of reasons, such as in heavy-duty applications.
Cycloid drives also have lower mass. These benefits make them ideally suited for all drive technologies. The design also allows for higher torsional stiffness and service life. These drives also have a much smaller profile.
Cycloid drives are also used to reduce speed. Because of the high torsional stiffness of the cycloid, they also have high positioning accuracy.
Cycloid drives are well-suited to a variety of applications, including electric motors, generators, and pump motors. They are also highly resistant to shock loads, which is important in a variety of applications. This design is ideal for applications that require a large transmission ratio in a compact design.
Cycloid drives also have the advantage of minimizing the clearance between the mating components. This helps to eliminate interference and ensure a positive fit. This is particularly important in gearboxes. It also allows for the use of a load cell and potentiometer to determine the backlash of the gearbox.
China Custom Drive Gear - 3222314238 - CZPT Gearbox for Drilling Machine   cycloidal drive efficiencyChina Custom Drive Gear - 3222314238 - CZPT Gearbox for Drilling Machine   cycloidal drive efficiency
editor by CX