High-bearing-capacity large-speed-ratio precise speed reduction device

Abstract

The invention relates to a high-bearing large-speed-ratio precise speed reducer which is characterized in that two end parts of a worm are rotatably supported on shell walls on two sides of the front end part of a shell, and one end of the worm is a power input end; two external thread sections with opposite rotation directions are arranged on the worm close to the two ends; the two worm gears are respectively meshed with two external thread sections on the worm; the two worm gears are coaxially and fixedly connected with one ends of the two eccentric shafts respectively; the two ends of the two eccentric shafts are rotationally supported at the two ends of the middle of the machine shell respectively. Two mounting holes in one planet wheel are respectively matched with one eccentric shaft neck in the same direction on the two eccentric shafts in a rotating and supporting manner; two mounting holes in the other planet wheel are respectively matched with the other eccentric shaft neck in the same direction on the two eccentric shafts in a rotating supporting manner; teeth on the outer rings of the two planet gears are meshed with inner teeth of the inner gear ring, and the two meshing positions are arranged at an angle of 180 degrees. The two sides of an inner hole of the inner gear ring are matched with the two ends of the middle of the machine shell in a rotating and supporting mode. The transmission is large in transmission ratio and small in size, and has a self-locking function.

Description

Technical Field

[0001] The invention belongs to the technical field of equipment transmission, and in particular relates to a high-load-bearing, large-speed-ratio precision reduction device. Background Art

[0002] The reducer is the most widely used mechanical device in the transmission field. As one of the four core technologies of industrial robots, it accounts for a large proportion of the production cost of industrial robots. In the existing technology, there are many types of planetary transmission devices with large transmission ratios, each with its own strengths and performance. However, the common problem faced by transmission devices with large transmission ratio spans is that the reducer structure of the angular rotation structure is large, the efficiency is low, the transmission accuracy is low, the structure is relatively complex, the load-bearing capacity is small, the assembly is difficult, and the manufacturing cost is high. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present invention proposes a high-load, high-speed-ratio precision reduction device which has a large transmission ratio, a small volume, a self-locking function, and can realize motion steering.

[0004] The above-mentioned object of the present invention is achieved by the following technical solutions:

[0005] A high-load, high-speed ratio precision reduction device, comprising a housing, a worm, two worm wheels, two eccentric shafts, two planetary wheels, and an inner gear ring; the worm is a power input component, and the inner gear ring is a power output component;

[0006] The two ends of the worm are rotatably supported on the two side walls of the front end of the casing, and one end extends out of the casing to form a power input end; two external thread sections with opposite rotation directions are provided near the two ends of the worm;

[0007] The spiral teeth of the outer rings of the two worm wheels are respectively meshed with the two external thread sections on the worm; the two worm wheels are respectively coaxially fixedly connected with one end of the two eccentric shafts through the center hole;

[0008] The two eccentric shafts are crank eccentric shafts with concentric shaft sections at both ends and two eccentric shaft necks at 180° to each other in the middle, and the two ends of the two eccentric shafts are rotatably supported at the two end positions in the middle of the casing respectively;

[0009] The two planetary wheels are disc gears with teeth on the outer ring and two mounting holes at 180 degrees on the wheel body. The two mounting holes on one planetary wheel respectively form a rotatable support with an eccentric shaft neck in the same direction on the two eccentric shafts; the two mounting holes on the other planetary wheel respectively form a rotatable support with another eccentric shaft neck in the same direction on the two eccentric shafts; the teeth on the outer rings of the two planetary wheels are meshed with the inner teeth of the inner gear ring, and the two meshing positions are arranged at 180 degrees;

[0010] The inner holes of the inner gear ring are located on both sides of the teeth and cooperate with the two ends of the rotation support in the middle of the casing. A flange is arranged in the middle of the outer ring of the inner gear ring, and a plurality of flange connection through holes for connecting with the output structural parts are arranged on the flange.

[0011] Moreover, the casing is composed of a front end shell and a rear end shell, and the two are fixedly connected by screws; the inner gear ring is coaxially arranged between the front end shell and the rear end shell; sealing rings are installed between the end surfaces in contact with the front end shell and the inner gear ring and between the end surfaces in contact with the rear end shell, so that a sealed installation cavity is formed inside the front end shell, the inner gear ring and the rear end shell.

[0012] The advantages and positive effects of the present invention are:

[0013] 1. The transmission part of the present invention adopts a symmetrical structure, which is compact and simple. The first-stage worm gear transmission ratio is i 1 ≈10~100, the second stage cycloid pin gear transmission ratio can reach i 2 ≈40~60, the total transmission ratio can reach i≈400~6000, thus achieving a large transmission ratio.

[0014] 2. The present invention adopts a combination of worm and worm gear transmission and cycloid planetary transmission. Compared with the existing cycloid planetary reducer, the first-stage reduction mechanism adopts helical gear transmission, which not only improves its gear meshing rate, transmission bearing capacity and running stability, improves its overload resistance and service life, but also can reduce the weight and working noise of the whole machine, and drives the flow of lubricating fluid inside the device through the operation of the helical gear, thereby improving the self-lubricating effect of various parts; in addition, based on the self-locking property of the worm and worm gear transmission mechanism, the reduction device of the present invention has a self-locking function.

[0015] 3. The device of the present invention has the advantages of small overall volume due to the small size of the worm gear and compact structure; the speed ratio of the worm pair is large, generally reaching 10 to 100, and has the advantages of self-locking characteristics, high load-bearing capacity and high rigidity; the transmission power and torque range of the device of the present invention is large, the power can be from a few kW to tens of kW, and the torque can be from hundreds of N·m to thousands of N·m; the present invention can set up a tightening device in the radial direction of the worm to adjust the distance between the axes of the worm pair, and with the help of the worm structure of the opposite rotation direction, the effect of adjusting the tooth gap can be achieved. For example, in the tightening device, a spring pre-tightening structure is introduced to realize the self-clearing function of the reducer. In addition, the device of the present invention has good processing and assembly processability and low manufacturing cost.

[0016] 4. The present invention uses the casing as a fixed component, transmits the rotational motion to the reduction mechanism through the worm pair, and realizes the steering. The same-direction rotation of the turbine is utilized, and with the help of the spline connection, the crankshafts on both sides are driven to rotate synchronously, thereby transmitting the power to the internal cycloid pin-tooth meshing mechanism, and finally realizing the rotational output of the pin-tooth housing, so that the rotation direction of the pin-tooth housing is 90° perpendicular to the rotation direction of the worm, thereby realizing the motion steering. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is the transmission principle diagram of the present invention;

[0018] Figure 2 It is a three-dimensional cross-sectional view of the present invention. DETAILED DESCRIPTION

[0019] The structure of the present invention is further described below with reference to the accompanying drawings and by way of examples. It should be noted that the present examples are descriptive rather than restrictive.

[0020] A high-load, high-speed ratio precision reduction device, see Figure 1-Figure 2 , including a casing 1, a worm 2, two worm wheels 3, two eccentric shafts 4, two planetary wheels 5, an inner gear ring 6, and a rolling bearing 7.

[0021] The casing is a fixed base member, and the casing 1 is an assemblable structure, and its exterior is provided with screw holes and pin holes connected to external mechanisms for connection and installation with the motor and external components, and its interior is provided with a supporting structure for a worm wheel and a worm, and a supporting structure for an eccentric shaft.

[0022] The worm 2 is a shaft-like structure, with the two ends of the worm supported on the two side walls of the front end of the housing through bearings, and one end extending from the housing, and a keyway, a coupling sleeve and other connection structures connected to the input end motor are provided at this end. Two external thread sections with opposite rotation directions are provided near the two ends of the worm for transmitting input rotational motion.

[0023] The two worm wheels are disc-type gear structures, and spline holes are provided in the centers of the two worm wheels for forming a spline transmission with one end of the eccentric shaft. The outer rings of the two worm wheels are respectively provided with helical teeth. The two worm wheels are respectively engaged with two external threaded sections on the worm through the helical teeth, and the external motion is redirected through the worm pair and transmitted to the planetary gear 5.

[0024] The two eccentric shafts 4 are crank eccentric shaft structures, one end of which is provided with an external spline for connecting to the worm gear, and the two ends are concentric shaft segment structures, which are used for positioning and supporting the casing 1, and can withstand axial and radial loads. Two eccentric shaft necks are provided in the middle at an angle of 180° to each other, which are respectively used to support rotatable planetary gears on both sides, and transmit the rotation of the worm gear 3 to the planetary gear 5.

[0025] The two planetary gears 5 have a disc gear structure with a hollow weight-reducing hole inside and an external tooth structure outside for meshing with the internal teeth in the inner gear ring 6. The two planetary gears are provided with two mounting holes at an angle of 180°. Bearings are installed in the mounting holes to form a rotatable support fit with the eccentric shaft necks in the same direction on the two eccentric shafts, thereby realizing the transmission of the rotational motion of the eccentric shaft to the inner gear ring through the gear pair.

[0026] The inner gear ring 6 is the power output part of the reduction device. The inner gear ring is an annular structure, and an inner gear structure is arranged in the middle of its inner hole. Bearing support surfaces are arranged on both sides of the inner hole. A bearing 7 is installed on each side to achieve coaxial rotation with the casing 1 and withstand axial and radial loads. A flange is arranged in the middle of its outer ring, and a plurality of flange connection through holes are arranged on the flange, which can be used to connect with the output structural parts.

[0027] The two eccentric shafts are connected to two planetary gears. The teeth on the outer rings of the two planetary gears connected to the two eccentric shaft necks of the eccentric shafts are meshed with the inner teeth of the inner gear ring, and the two meshing positions are set at 180 degrees to achieve double-sided torque drive of the inner gear ring. The meshing gear pair of the planetary gear and the inner gear ring adopts a pin-tooth structure. The cycloid gear and the pin-tooth transmission pair are a small-tooth-difference planetary transmission gear pair. The speed ratio of the gear pair is generally 40 to 60, and the single-stage reduction ratio of the small-tooth-difference planetary transmission gear pair is 10 to 100.

[0028] In the above structure, the housing is composed of a front housing and a rear housing, which are fixedly connected by a circle of screws, and the inner gear ring is coaxially arranged between the front housing and the rear housing; a sealing ring is installed between the end faces of the front housing and the inner gear ring and between the end faces of the inner gear ring and the rear housing, so that a sealed installation cavity is formed inside the front housing, the inner gear ring and the rear housing. The front housing is mainly used to install the worm and accommodate the worm and the worm wheel, and the space between the front housing and the rear housing is used to install two eccentric shafts, two planetary gears and the inner gear ring.

[0029] The working principle of the high-load and high-speed ratio precision reduction device of the present invention is:

[0030] High-speed rotational power is transmitted from the worm 2, and the spiral tooth part of the worm 2 drives the eccentric shaft 4 to rotate by meshing with the worm wheel 3, and the planetary gear 5 is meshed with the pin teeth on the inner ring gear 6 to realize the speed reduction output of the inner ring gear 6.

[0031] Although the embodiments and drawings of the present invention are disclosed for illustrative purposes, those skilled in the art will appreciate that various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A high-load, high-speed ratio precision reduction device, characterized in that: It includes a casing, a worm, two worm wheels, two eccentric shafts, two planetary wheels, and an inner gear ring; the worm is a power input component, and the inner gear ring is a power output component; The two ends of the worm are rotatably supported on the two side walls of the front end of the casing, and one end extends out of the casing to form a power input end; two external thread sections with opposite rotation directions are provided near the two ends of the worm; The spiral teeth of the outer rings of the two worm wheels are respectively meshed with the two external thread sections on the worm; the two worm wheels are respectively coaxially fixedly connected with one end of the two eccentric shafts through the center hole; The two eccentric shafts are crank eccentric shafts with concentric shaft sections at both ends and two eccentric shaft necks at 180° to each other in the middle, and the two ends of the two eccentric shafts are rotatably supported at the two end positions in the middle of the casing respectively; The two planetary wheels are disc gears with teeth on the outer ring and two mounting holes at 180 degrees on the wheel body. The two mounting holes on one planetary wheel respectively form a rotatable support with an eccentric shaft neck in the same direction on the two eccentric shafts; the two mounting holes on the other planetary wheel respectively form a rotatable support with another eccentric shaft neck in the same direction on the two eccentric shafts; the teeth on the outer rings of the two planetary wheels are meshed with the inner teeth of the inner gear ring, and the two meshing positions are arranged at 180 degrees; The inner holes of the inner gear ring are located on both sides of the teeth and cooperate with the two ends of the rotation support in the middle of the casing. A flange is arranged in the middle of the outer ring of the inner gear ring, and a plurality of flange connection through holes for connecting with the output structural parts are arranged on the flange.

2. The high-load, high-speed ratio precision reduction device according to claim 1 is characterized in that: The housing is composed of a front end housing and a rear end housing, which are fixedly connected by screws; the inner gear ring is coaxially arranged between the front end housing and the rear end housing; sealing rings are installed between the end surfaces contacting the front end housing and the inner gear ring and between the end surfaces contacting the inner gear ring and the rear end housing, so that a sealed installation cavity is formed inside the front end housing, the inner gear ring and the rear end housing.

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