Large hollow thin-wall precise speed reducer

Abstract

The invention relates to a large hollow thin-wall precise speed reducer. The head end inner gear ring gland and the tail end inner gear ring gland are coaxially and fixedly connected with the head end and the tail end of the inner gear ring respectively to form a base frame; the crankshaft is a large hollow thin-wall shaft, and the middle of the crankshaft is of an eccentric outer circle structure. A crankshaft is installed in an inner hole of the base frame in a penetrating mode, the portion, close to the head end inner gear ring gland, of the crankshaft is matched with the inner hole of the base frame in a rotating supporting mode through a crossed roller bearing, and the end, close to the tail end inner gear ring gland, of the crankshaft is matched with an inner ring of a power output ring in a rotating supporting mode through a first set of needle bearings. The outer ring of the power output ring is rotationally supported and matched with the inner hole of the base frame close to the tail end part through a second group of needle bearings; the planet gear is arranged on the eccentric outer circle of the crankshaft in a sleeving mode through a third set of needle bearings, and the planet gear is meshed with the inner gear ring and is of a small-tooth-difference structural form; the two ends of the force transmission ring are connected with the tail end of the planet wheel and the head end of the power output ring in a cross-shaped sliding block connection mode. The invention has the characteristics of large mesopore, light weight and high rigidity.

Description

Technical Field

[0001] The invention belongs to the technical field of equipment transmission, and in particular relates to a large hollow thin-wall precision speed reducer. Background Art

[0002] With the continuous upgrading and transformation of the manufacturing industry, especially in the rise of high-end manufacturing, the demand for precision transmission devices such as large hollow reducers has increased significantly. Large hollow reducers have become the first choice of many companies due to their high precision, high load-bearing capacity and unique structural form, including not only traditional manufacturing industries, but also new energy industries, medical equipment, aviation, marine and other fields. These fields require reducers not only high precision and stability, but also hollowness. Large hollowness (i.e. small wall thickness) can achieve lightweight reducer, and more importantly, it can be adapted to special scenarios with limited space. Summary of the invention

[0003] In view of the deficiencies in the prior art, the present invention provides a large hollow thin-wall precision speed reducer.

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

[0005] A large hollow thin-wall precision speed reducer, comprising a crankshaft, a planetary gear, an inner gear ring, a force transmission ring, a power output ring, a cross roller bearing, three sets of needle bearings, a head end inner gear ring gland and a tail end inner gear ring gland;

[0006] The head end inner gear ring pressure cover is coaxially fixedly connected to the head end of the inner gear ring, and the tail end inner gear ring pressure cover is coaxially fixedly connected to the tail end of the inner gear ring, and the three constitute a base frame of the reduction device;

[0007] The crankshaft adopts a large hollow thin-walled shaft, and the middle part of the crankshaft adopts an eccentric outer circle structure; the crankshaft is installed in the inner hole of the base frame, and the part of the crankshaft close to the inner gear ring pressure cover at the head end forms a rotation support cooperation with the inner hole of the base frame through a cross roller bearing, and one end of the crankshaft close to the inner gear ring pressure cover at the tail end forms a rotation support cooperation with the inner ring of the power output ring through a first group of needle bearings, and the outer ring of the power output ring forms a rotation support cooperation with the part of the inner hole of the base frame close to the tail end through a second group of needle bearings;

[0008] The planetary gear is rotatably sleeved on the eccentric outer circle of the middle part of the crankshaft through a third set of needle bearings, the planetary gear is meshed with the inner gear ring, the number of teeth of the planetary gear is less than that of the inner gear ring, forming a structure with a small tooth difference;

[0009] The force transmission ring is sleeved on the outside of the crank shaft and is arranged between the tail end of the planetary wheel and the head end of the power output ring. The two ends of the force transmission ring are connected to the tail end of the planetary wheel and the head end of the power output ring by a cross slider, so as to realize the transmission of the rotation of the planetary wheel to the power output ring and finally realize the output of power.

[0010] Moreover, two through sockets with an angle of 180° are arranged at the tail end of the planetary wheel, and two convex plug-in blocks with an angle of 180° are arranged at the end of the force transmission ring close to the planetary wheel, and the two convex plug-in blocks are respectively embedded in the two through sockets on the planetary wheel, so as to realize the transmission of the torque of the planetary wheel to the force transmission ring; two through sockets with an angle of 180° are arranged on the end face of the force transmission ring close to the power output ring, and the two through sockets are clamped at 90° with the convex plug-in blocks on the other side, and at the same time, two convex plug-in blocks with an angle of 180° are arranged at the inner end of the power output ring, and the two convex plug-in blocks on the power output ring are respectively embedded in the two through sockets on the force transmission ring, so as to realize the transmission of the torque of the force transmission ring to the power output ring.

[0011] Moreover, bearing positioning circular grooves are provided on the inner side surface of the inner gear ring pressure cover at the head end and the head end of the inner gear ring, and the outer ring of the cross roller bearing is embedded in the bearing positioning circular grooves on both sides to realize the radial positioning of the bearing and the axial positioning of the outer ring; a first bearing limiting surface and a retaining spring mounting groove are provided on the outer ring of the crank shaft near the head end, and an earless retaining spring for the shaft is installed in the retaining spring mounting groove, one end of the inner ring of the cross roller bearing contacts with the first bearing limiting surface, and the other end contacts with the inner side surface of the earless retaining spring for the shaft to realize the axial limitation of the inner ring of the cross roller bearing.

[0012] Moreover, a second bearing limiting surface is arranged on the outer ring of the crank shaft near the tail end, and an inner bearing positioning surface is arranged on the inner ring of the power output ring near the head end; one end of the first group of needle roller bearings contacts with the second bearing limiting surface, and the other end of the first group of needle roller bearings contacts with the inner bearing positioning surface, thereby realizing axial limitation of the first group of needle roller bearings.

[0013] Moreover, an outer bearing positioning surface is arranged on the outer ring of the power output ring near the head end; one end of the second set of needle roller bearings contacts the outer bearing positioning surface, and the other end contacts the inner end surface of the inner gear ring pressure cover at the tail end, thereby realizing axial limitation of the second set of needle roller bearings.

[0014] Moreover, a first O-ring is installed on the outside of the earless retaining ring installed between the inner ring of the inner gear ring cover at the head end and the outer ring of the crank shaft; a second O-ring is installed on the outside of the first group of needle bearings between the outer ring of the crank shaft and the inner ring of the power output ring; and a third O-ring is installed on the outside of the second group of needle bearings between the outer ring of the power output ring and the inner ring of the inner gear ring cover at the tail end.

[0015] Moreover, four force transmission protrusions are evenly arranged along the circumferential direction at the head end of the crank shaft and the tail end of the power output ring.

[0016] The advantages and positive effects of the present invention are:

[0017] 1. The crankshaft of the present invention adopts a large hollow thin-wall structure, the meshing transmission mechanism adopts a small tooth difference structure of a planetary gear and an inner gear ring, and needle bearings are used for support between multiple relatively rotating parts. While meeting the use scenario of the large hollow, the radial size of the reduction device is minimized. In addition, a force transmission ring is arranged between the planetary gear and the power output ring, and torque transmission is achieved through an embedded cross slider structure, which realizes structural simplification and minimization of the axis size, thereby achieving the purpose of lightweighting the reduction device.

[0018] 2. The present invention adopts a multi-needle roller design, which also realizes the structural characteristics of high rigidity of the whole machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is an overall cross-sectional view of the present invention;

[0020] Figure 2 It is an overall three-dimensional exploded view of the present invention;

[0021] Figure 3 It is the transmission principle diagram of the present invention;

[0022] Figure 4 is a schematic cross-sectional view of the meshing of gears of the present invention;

[0023] Figure 5 is a schematic cross-sectional view of the head end of the force transmission ring of the present invention;

[0024] Figure 6 It is a schematic cross-sectional view of the tail end of the force transmission ring of the present invention. DETAILED DESCRIPTION

[0025] 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.

[0026] A large hollow thin wall precision speed reducer, see Figure 1-Figure 6 The invention point is: it includes a crankshaft 3, a planetary gear 7, an inner gear ring 8, a force transmission ring 9, a power output ring 14, a cross roller bearing 5, three sets of needle bearings, a shaft earless retainer 4, three O-rings, a head end inner gear ring gland 1 and a tail end inner gear ring gland 13. The three sets of needle bearings are respectively a first set of needle bearings 10, a second set of needle bearings 11, and a third set of needle bearings 6. The three O-rings are respectively a first O-ring 2, a second O-ring 16, and a third O-ring 15.

[0027] The head end inner gear ring pressure cover is coaxially fixedly connected to the head end of the inner gear ring by screws, and the tail end inner gear ring pressure cover is fixedly connected to the tail end of the inner gear ring by screws 12, and the three constitute the base frame of the reduction device.

[0028] The crankshaft adopts a large hollow thin-walled shaft, and the middle part of the crankshaft adopts an eccentric outer circle structure. The crankshaft is installed in the inner hole of the base frame, and the part of the crankshaft near the head end inner gear ring gland forms a rotation support match with the inner hole of the base frame through a cross roller bearing, and one end of the crankshaft near the tail end inner gear ring gland forms a rotation support match with the inner ring of the power output ring through a first set of needle bearings 10, and the outer ring of the power output ring forms a rotation support match with the part of the inner hole of the base frame near the tail end through a second set of needle bearings 11.

[0029] In order to achieve radial and axial positioning of the crossed roller bearing, a bearing positioning circular groove is provided on the inner side surface of the head end inner gear ring pressure cover and the head end of the inner gear ring. The diameter of the bearing positioning groove is consistent with the outer diameter of the crossed roller bearing, and the distance between the bottoms of the two bearing positioning circular grooves is consistent with the thickness of the crossed roller bearing. The outer ring of the crossed roller bearing is embedded in the bearing positioning circular grooves on both sides to achieve radial positioning of the bearing and axial positioning of the outer ring. In addition, a first bearing limiting surface and a retaining ring installation groove are provided on the outer ring of the crankshaft near the head end, and an earless retaining ring for the shaft is installed in the retaining ring installation groove. One end of the inner ring of the crossed roller bearing contacts the first bearing limiting surface, and the other end contacts the inner side surface of the earless retaining ring for the shaft to achieve axial positioning of the inner ring of the crossed roller bearing.

[0030] The above-mentioned limiting method for the first group of needle roller bearings is as follows: a second bearing limiting surface is arranged on the outer ring of the crank shaft near the tail end, and an inner bearing positioning surface is arranged on the inner ring of the power output ring near the head end; one end of the first group of needle roller bearings contacts with the second bearing limiting surface, and the other end of the first group of needle roller bearings contacts with the inner bearing positioning surface, thereby realizing axial limiting of the first group of needle roller bearings.

[0031] The above-mentioned limiting method for the second group of needle roller bearings is: an outer bearing positioning surface is set on the outer ring of the power output ring near the head end; one end of the second group of needle roller bearings contacts with the outer bearing positioning surface, and the other end contacts with the inner end surface of the inner gear ring pressure cover at the tail end, thereby realizing the axial limiting of the second group of needle roller bearings.

[0032] The planetary gear is rotatably sleeved on the eccentric outer circle of the middle part of the crankshaft through the third set of needle bearings 6. The planetary gear is meshed with the inner gear ring. The number of teeth of the planetary gear is less than that of the inner gear ring, forming a small tooth difference structure, which greatly improves the transmission ratio of the reduction device itself. The above crankshaft is connected to an external power drive. The planetary gear is in contact and meshing with the inner gear ring. Due to the eccentric design characteristics of the crankshaft, the planetary gear produces a reverse deceleration motion under the action of the contact force.

[0033] The force transmission ring is sleeved on the outside of the crankshaft and is arranged between the tail end of the planetary wheel and the head end of the power output ring, and is used to transmit the rotation of the planetary wheel to the power output ring and finally realize the output of power.

[0034] Since the movement of the planetary wheel is an eccentric rotational movement, and the power output ring is arranged concentrically with the crankshaft. In order to transmit the rotational movement of the planetary wheel to the power output ring, a cross slider connection is adopted between the two ends of the force transmission ring and the tail end of the planetary wheel and the head end of the power output ring. Specifically, two through sockets with an angle of 180° can be set at the tail end of the planetary wheel, and two convex plug-in blocks with an angle of 180° are set at the end of the force transmission ring close to the planetary wheel. The two convex plug-in blocks are respectively embedded in the two through sockets on the planetary wheel to transmit the torque of the planetary wheel to the force transmission ring. Two through sockets with an angle of 180° are set on the end face of the force transmission ring close to the power output ring. The two through sockets are clamped at 90° with the convex plug-in blocks on the other side. At the same time, two convex plug-in blocks with an angle of 180° are set at the inner end of the power output ring. The two convex plug-in blocks on the power output ring are respectively embedded in the two through sockets on the force transmission ring to transmit the torque of the force transmission ring to the power output ring.

[0035] During the meshing transmission between the planetary gear and the inner gear ring, the force transmission ring will automatically fine-tune its position in the radial direction to achieve smooth torque transmission. Sufficient clearance is left between the inner ring of the force transmission ring and the corresponding part of the crankshaft, and between the outer ring of the force transmission ring and the corresponding part of the inner ring of the base frame.

[0036] In order to prevent impurities in the use environment from entering the interior of the reduction gear and causing adverse effects on gear meshing and bearings, a first O-ring is installed on the outer side of the inner ring of the head end inner gear ring gland and the outer ring of the crank shaft where the earless retaining ring is installed. This can be achieved by providing a sealing ring installation groove on the inner ring of the head end inner gear ring gland. A second O-ring 16 is installed on the outer side of the first set of needle roller bearings between the outer ring of the crank shaft and the inner ring of the power output ring. This can be achieved by providing a sealing ring installation groove on the inner ring of the power output ring. A third O-ring 15 is installed on the outer side of the second set of needle roller bearings between the outer ring of the power output ring and the inner ring of the tail end inner gear ring gland. This can be achieved by providing a sealing ring installation groove on the outer ring of the power output ring.

[0037] In addition to the above main technical features, in order to facilitate the connection between the reduction device and the power source and the load, four force transmission protrusions are evenly arranged along the circumferential direction at the head end of the crankshaft, which can realize the quick plug-in connection with the power source. In addition, four force transmission protrusions are evenly arranged along the circumferential direction at the tail end of the power output ring, which can realize the quick plug-in connection with the load.

[0038] The transmission principle of the large hollow thin-wall precision speed reducer of the present invention is:

[0039] The crankshaft is connected to the external power drive. The planetary gear is in contact and meshing with the inner gear ring. Due to the eccentric design of the crankshaft, the planetary gear produces a reverse deceleration motion under the action of the contact force. The planetary gear and the force transmission ring, and the force transmission ring and the power output ring are connected by a cross slider. The movement of the planetary gear finally reaches the output ring through the force transmission ring, forming the final deceleration motion output.

[0040] The reduction gear device of the present invention can meet the requirements of the use scenario for the reducer's inner and outer diameter dimensions to be extremely close, adopt a large hollow structure inside, facilitate internal wiring while reducing the reducer's own weight, and at the same time achieve the structural characteristics of high rigidity of the entire machine.

[0041] 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 large hollow thin-wall precision speed reducer, characterized in that: It includes a crankshaft, a planetary gear, an inner gear ring, a force transmission ring, a power output ring, a cross roller bearing, three sets of needle bearings, a head end inner gear ring gland and a tail end inner gear ring gland; The head end inner gear ring pressure cover is coaxially fixedly connected to the head end of the inner gear ring, and the tail end inner gear ring pressure cover is coaxially fixedly connected to the tail end of the inner gear ring, and the three constitute a base frame of the reduction device; The crankshaft adopts a large hollow thin-walled shaft, and the middle part of the crankshaft adopts an eccentric outer circle structure; the crankshaft is installed in the inner hole of the base frame, and the part of the crankshaft close to the inner gear ring pressure cover at the head end forms a rotation support cooperation with the inner hole of the base frame through a cross roller bearing, and one end of the crankshaft close to the inner gear ring pressure cover at the tail end forms a rotation support cooperation with the inner ring of the power output ring through a first group of needle bearings, and the outer ring of the power output ring forms a rotation support cooperation with the part of the inner hole of the base frame close to the tail end through a second group of needle bearings; The planetary gear is rotatably sleeved on the eccentric outer circle of the middle part of the crankshaft through a third set of needle bearings, the planetary gear is meshed with the inner gear ring, the number of teeth of the planetary gear is less than that of the inner gear ring, forming a structure with a small tooth difference; The force transmission ring is sleeved on the outside of the crank shaft and is arranged between the tail end of the planetary wheel and the head end of the power output ring. The two ends of the force transmission ring are connected to the tail end of the planetary wheel and the head end of the power output ring by a cross slider to transmit the rotation of the planetary wheel to the power output ring and finally realize the output of power.

2. The large hollow thin-wall precision speed reducer according to claim 1 is characterized in that: Two through sockets at an angle of 180° are arranged at the tail end of the planetary wheel, and two convex plug-in blocks at an angle of 180° are arranged at the end of the force transmission ring close to the planetary wheel. The two convex plug-in blocks are respectively embedded in the two through sockets on the planetary wheel, so as to transmit the torque of the planetary wheel to the force transmission ring; two through sockets at an angle of 180° are arranged on the end face of the force transmission ring close to the power output ring, and the two through sockets are clamped at 90° with the convex plug-in blocks on the other side. At the same time, two convex plug-in blocks at an angle of 180° are arranged at the inner end of the power output ring, and the two convex plug-in blocks on the power output ring are respectively embedded in the two through sockets on the force transmission ring, so as to transmit the torque of the force transmission ring to the power output ring.

3. The large hollow thin-wall precision speed reducer according to claim 1 is characterized in that: Bearing positioning circular grooves are provided on the inner side surface of the inner gear ring pressure cover at the head end and the head end of the inner gear ring. The outer ring of the cross roller bearing is embedded in the bearing positioning circular grooves on both sides to realize the radial positioning of the bearing and the axial positioning of the outer ring; a first bearing limiting surface and a retaining ring installation groove are provided on the outer ring of the crank shaft near the head end, and an earless retaining ring for the shaft is installed in the retaining ring installation groove. One end of the inner ring of the cross roller bearing contacts with the first bearing limiting surface, and the other end contacts with the inner side surface of the earless retaining ring for the shaft to realize the axial limitation of the inner ring of the cross roller bearing.

4. The large hollow thin-wall precision speed reducer according to claim 1 is characterized in that: A second bearing limiting surface is arranged on the outer ring of the crank shaft near the tail end, and an inner bearing positioning surface is arranged on the inner ring of the power output ring near the head end; one end of the first group of needle roller bearings contacts with the second bearing limiting surface, and the other end of the first group of needle roller bearings contacts with the inner bearing positioning surface, thereby realizing axial limiting of the first group of needle roller bearings.

5. The large hollow thin-wall precision speed reducer according to claim 1 is characterized in that: An outer bearing positioning surface is arranged on the outer ring of the power output ring near the head end; one end of the second set of needle roller bearings contacts the outer bearing positioning surface, and the other end contacts the inner end surface of the inner gear ring pressure cover at the tail end, thereby realizing axial limitation of the second set of needle roller bearings.

6. The large hollow thin-wall precision speed reducer according to claim 1 is characterized in that: A first O-ring is installed on the outside of the earless retaining ring installed between the inner ring of the inner gear ring cover at the head end and the outer ring of the crank shaft; a second O-ring is installed on the outside of the first group of needle bearings between the outer ring of the crank shaft and the inner ring of the power output ring; and a third O-ring is installed on the outside of the second group of needle bearings between the outer ring of the power output ring and the inner ring of the inner gear ring cover at the tail end.

7. The large hollow thin-wall precision speed reducer according to claim 1 is characterized in that: Four force transmission protrusions are evenly arranged along the circumferential direction at the head end of the crank shaft and the tail end of the power output ring.

Images