A coaxial planetary gear reducer with shell cooling

Abstract

An embodiment of the present invention discloses a coaxial planetary gear reducer with shell cooling. In this reducer, by setting an annular oil baffle, a oil storage cavity is formed by the gap between the annular oil baffle and the connecting wall. By setting an upper notch and a lower notch on the annular oil baffle, most of the lubricating oil remains in the oil storage cavity, and a small part of the lubricating oil flows back to the oil storage tank through the lower notch directly below the outer wall of the annular oil baffle. Further, when the coaxial planetary gear reducer is working, the amount of lubricating oil in the oil storage tank agitated by the planet carrier is reduced, so the churning loss is reduced. At the same time, the resistance of the lubricating oil to each component of the coaxial planetary gear reducer during movement is reduced, the working efficiency is improved, and the friction between each component of the coaxial planetary gear reducer and the lubricating oil is also reduced, reducing the heat generation of the coaxial planetary gear reducer.

Description

Technical Field

[0001] The present invention relates to the technical field of speed reducers, and more particularly, to a coaxial planetary gear speed reducer with shell cooling. Background Art

[0002] Currently, the lubricating oil of the planetary gear speed reducer is stored below the housing. When the planetary gear speed reducer is working, the planet carrier of the planetary gear speed reducer rotates and stirs the lubricating oil below the housing, causing the lubricating oil to splash so as to lubricate each component inside the housing.

[0003] Since the planet carrier stirs a large amount of lubricating oil, the oil stirring loss of the planetary gear speed reducer is very serious. Moreover, when each component of the planetary gear speed reducer is moving, due to the resistance of the lubricating oil, the working efficiency is low, and each component of the planetary gear speed reducer will rub against the lubricating oil, resulting in serious heating of the planetary gear speed reducer. Summary of the Invention

[0004] The present invention provides a coaxial planetary gear speed reducer with shell cooling to reduce oil stirring loss, improve working efficiency and reduce heating. The specific technical solutions are as follows:

[0005] In a first aspect, the present invention provides a coaxial planetary gear speed reducer with shell cooling, including a sun gear, a plurality of planetary gears, a planet carrier, a ring gear, an annular oil baffle and a housing;

[0006] The housing includes a first chamber and a second chamber that are interconnected and connected to each other by a connecting wall. The diameter of the first chamber is larger than that of the second chamber. The sun gear, the planet carrier, the ring gear and the annular oil baffle are coaxial. The axis of each planetary gear is parallel to the axis of the sun gear, and the sun gear, the plurality of planetary gears, the planet carrier, the ring gear and the annular oil baffle are all installed in the first chamber;

[0007] The power input shaft is connected to the sun gear. The sun gear is externally meshed with the plurality of planetary gears. The plurality of planetary gears are drivingly connected to the planet carrier. The planet carrier is connected to the power output shaft. The power output shaft is installed in the second chamber. The plurality of planetary gears are internally meshed with the ring gear. The ring gear is fixedly installed on the inner wall of the first chamber. A lubricating oil storage groove for storing lubricating oil is provided below the inner wall of the first chamber adjacent to the planet carrier;

[0008] The annular oil baffle is sleeved on the planet carrier. The outer wall of the annular oil baffle is in clearance fit with the inner wall of the first chamber, and the annular oil baffle is fixedly connected to the inner side of the connecting wall. A oil storage cavity is formed by the gap between the annular oil baffle and the connecting wall. An upper notch is arranged above the outer wall of the annular oil baffle, and a lower notch is arranged directly below the outer wall of the annular oil baffle. The size of the upper notch is larger than that of the lower notch.

[0009] Optionally, a cooling oil passage is arranged on the outer side of the connecting wall.

[0010] Optionally, the coaxial planetary gear reducer with housing cooling further includes a breather plug. A vent hole is arranged above the inner wall of the first chamber near the oil storage cavity, and the position of the vent hole is far from the upper notch. The breather plug is installed in the vent hole.

[0011] Optionally, the coaxial planetary gear reducer with housing cooling further includes tapered roller bearings. The power output shaft is installed in the second chamber through the tapered roller bearings, and an oil supply passage leading to the tapered roller bearings is arranged on the inner side of the connecting wall.

[0012] Optionally, a protrusion is arranged on the outer periphery of the ring gear, and a clamping groove is arranged on the inner wall of the first chamber. The ring gear is clamped into the clamping groove through the protrusion.

[0013] Optionally, a plurality of first bolt holes with protrusions spaced circumferentially around the center are arranged on the inner side of the connecting wall, and a plurality of second bolt holes spaced circumferentially around the center are arranged on the annular oil baffle. The first bolt holes and the second bolt holes are connected by bolts.

[0014] Optionally, the planet carrier includes a plurality of mounting shafts. The axis of each mounting shaft is parallel to the axis of the sun gear. The plurality of planetary gears are respectively installed on the plurality of mounting shafts through bearings. Wherein, the number of the mounting shafts is the same as the number of the planetary gears.

[0015] Optionally, the number of the planetary gears is three.

[0016] Optionally, the number of the upper notches is four, and the number of the lower notches is one.

[0017] Optionally, the planet carrier and the power output shaft are integrally formed.

[0018] As can be seen from the above, in this embodiment, by providing an annular oil baffle, a oil storage cavity is formed by the gap between the annular oil baffle and the connecting wall. By providing an upper notch and a lower notch on the annular oil baffle, most of the lubricating oil remains in the oil storage cavity, and a small part of the lubricating oil flows back to the oil storage tank through the lower notch directly below the outer wall of the annular oil baffle. Further, when the coaxial planetary gear reducer is working, the amount of lubricating oil in the oil storage tank agitated by the planet carrier is reduced, so the churning loss is reduced. At the same time, the resistance of the lubricating oil to each component of the coaxial planetary gear reducer during movement is reduced, the working efficiency is improved, and the friction between each component of the coaxial planetary gear reducer and the lubricating oil is also reduced, reducing the heat generation of the coaxial planetary gear reducer. Of course, it is not necessary for any product or method implementing the present invention to achieve all of the above advantages simultaneously.

[0019] The innovative points of the embodiments of the present invention include:

[0020] 1. By providing an annular oil baffle, a oil storage cavity is formed by the gap between the annular oil baffle and the connecting wall. By providing an upper notch and a lower notch on the annular oil baffle, most of the lubricating oil remains in the oil storage cavity, and a small part of the lubricating oil flows back to the oil storage tank through the lower notch directly below the outer wall of the annular oil baffle. Further, when the coaxial planetary gear reducer is working, the amount of lubricating oil in the oil storage tank agitated by the planet carrier is reduced, so the churning loss is reduced. At the same time, the resistance of the lubricating oil to each component of the coaxial planetary gear reducer during movement is reduced, the working efficiency is improved, and the friction between each component of the coaxial planetary gear reducer and the lubricating oil is also reduced, reducing the heat generation of the coaxial planetary gear reducer.

[0021] 2. Since the gap between the annular oil baffle and the connecting wall forms a oil storage cavity, and the cooling oil passage is arranged outside the connecting wall, the cooling oil passage is close to the oil storage cavity. Also, when the coaxial planetary gear reducer is working, most of the lubricating oil remains in the oil storage cavity, and the lubricating oil in the oil storage cavity does not splash everywhere, so that the cooling oil passage can contact more lubricating oil in the oil storage cavity through the connecting wall, improving the heat exchange efficiency and further improving the cooling effect.

[0022] 3. Since when the coaxial planetary gear reducer is working, the planet carrier rotates and agitates the lubricating oil in the oil storage tank, the flow rate of the lubricating oil in the oil storage cavity is relatively low, and the position of the vent hole is far from the upper notch. Therefore, the lubricating oil is not easily leaked from the vent plug, reducing the probability of vent plug oil leakage.

[0023] 4. Since an oil supply channel leading to the tapered roller bearing is provided on the inner side of the connecting wall, during the operation of the coaxial planetary gear reducer, the lubricating oil in the oil storage cavity can be transported along the oil supply channel to the tapered roller bearing through the oil supply channel, ensuring the normal operation of the tapered roller bearing. Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] Figure 1 A cross-sectional view of the coaxial planetary gear reducer with shell cooling provided by an embodiment of the invention from an angle;

[0026] Figure 2 A cross-sectional view of the housing provided by an embodiment of the present invention from an angle;

[0027] Figure 3 A structural view of the housing provided by an embodiment of the present invention from an angle;

[0028] Figure 4 A structural view of the annular oil baffle provided by an embodiment of the present invention;

[0029] Figure 5 A structural view of the housing provided by an embodiment of the present invention from another angle;

[0030] Figure 6 A structural view of the cooling oil channel provided by an embodiment of the present invention.

[0031] Figures 1 - 6 In the figure, 1 is the sun gear, 2 is the planetary gear, 3 is the planet carrier, 4 is the ring gear, 5 is the annular oil baffle, 51 is the second bolt hole, 52 is the upper notch, 53 is the lower notch, 6 is the housing, 61 is the connecting wall, 611 is the first bolt hole, 62 is the first chamber, 63 is the second chamber, 7 is the oil storage cavity, 8 is the cooling oil channel, 9 is the breather plug, 10 is the tapered roller bearing, and 11 is the oil supply channel. Detailed Embodiments

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0033] It should be noted that the terms "including" and "having" and any variations thereof in the embodiments of the present invention and the accompanying drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0034] The embodiment of the present invention discloses a coaxial planetary gear reducer with shell cooling, which can reduce oil stirring loss, improve working efficiency and reduce heat generation. The embodiment of the present invention is described in detail below.

[0035] Figure 1 A schematic cross-sectional view at one angle of a coaxial planetary gear reducer with shell cooling provided in an embodiment of the present invention. Figure 2 A schematic cross-sectional view at an angle of a housing provided in an embodiment of the present invention.

[0036] See also Figure 1 The coaxial planetary gear reducer with shell cooling provided in an embodiment of the present invention includes a sun gear 1, a plurality of planetary gears 2, a planet carrier 3, a ring gear 4, an annular oil baffle 5 and a shell 6.

[0037] See also Figure 2 The housing 6 includes a first chamber 62 and a second chamber 63 which are interconnected and connected to each other through a connecting wall 61 .

[0038] Since the sun gear 1 , the plurality of planetary gears 2 , the planet carrier 3 , the ring gear 4 and the annular oil baffle 5 are all installed in the first chamber 62 , the diameter of the first chamber 62 is relatively large, and the diameter of the first chamber 62 is greater than the diameter of the second chamber 63 .

[0039] Continue to see Figure 1 , the sun gear 1, the planet carrier 3, the gear ring 4 and the annular oil baffle 5 are coaxial, and the axis of each planetary gear 2 is parallel to the axis of the sun gear 1. The sun gear 1 is rigidly connected to the power input shaft as the power input end, that is, the power input shaft is connected to the sun gear 1. The sun gear 1 is externally meshed with a plurality of planetary gears 2, and the plurality of planetary gears 2 are transmission-connected to the planet carrier 3. Exemplarily, the planet carrier 3 includes a plurality of mounting shafts, and the axis of each mounting shaft is parallel to the axis of the sun gear 1. The plurality of planetary gears 2 are respectively mounted on the plurality of mounting shafts through bearings, wherein the number of mounting shafts is the same as the number of planetary gears 2.

[0040] Exemplarily, the number of the planetary gears 2 is three.

[0041] Continue to see Figure 1The planet carrier 3 is rigidly connected to the power output shaft as the power output end, that is, the planet carrier 3 is connected to the power output shaft. For example, the planet carrier 3 can be integrally formed with the power output shaft.

[0042] Continue to see Figure 1 The power output shaft is installed in the second chamber 63, and multiple planetary gears 2 are meshed with the ring gear 4. The ring gear 4 is fixedly installed on the inner wall of the first chamber 62. Exemplarily, a protrusion is provided on the outer periphery of the ring gear 4, and a groove is provided on the inner wall of the first chamber 62. The ring gear 4 is inserted into the groove through the protrusion, thereby fixing the ring gear 4 to the inner wall of the first chamber 62.

[0043] Continue to see Figure 1 The annular oil baffle plate 5 is sleeved on the planet carrier 3 , the outer wall of the annular oil baffle plate 5 is gap-matched with the inner wall of the first chamber 62 , and the annular oil baffle plate 5 is fixedly connected to the inner side of the connecting wall 61 .

[0044] For example, see Figure 3 and Figure 4 , Figure 3 This is a schematic structural diagram of a housing 6 provided at an angle according to an embodiment of the present invention. Figure 4 A schematic diagram of the structure of the annular oil baffle plate 5 provided in an embodiment of the present invention. The inner side of the connecting wall 61 is provided with a plurality of protruding first bolt holes 611 spaced apart around the center circumference, and the annular oil baffle plate 5 is provided with a plurality of second bolt holes 51 spaced apart around the center circumference, and the first bolt holes 611 and the second bolt holes 51 are connected by bolts.

[0045] Thus, the annular oil baffle plate 5 is fixedly connected to the inner side of the connecting wall 61 by bolts.

[0046] Continue to see Figure 2 and Figure 4 The gap between the annular oil baffle plate 5 and the connecting wall 61 forms an oil storage cavity 7, an upper notch 52 is provided above the outer wall of the annular oil baffle plate 5, and a lower notch 53 is provided just below the outer wall of the annular oil baffle plate 5, and the size of the upper notch 52 is larger than the size of the lower notch 53.

[0047] For example, the number of the upper notches 52 may be four, and the number of the lower notch 53 may be one.

[0048] When the coaxial planetary gear reducer provided by the embodiment of the present invention is working, the power input shaft drives the sun gear 1 to rotate. Since the multiple planetary gears 2 are transmission-connected to the planet carrier 3 and are respectively meshed with the sun gear 1 externally and the ring gear 4 internally, the sun gear 1 drives the multiple planetary gears 2 to revolve and rotate.

[0049] Multiple planetary gears 2 drive the planet carrier 3 to rotate. Since an oil storage groove for storing lubricating oil is provided below the inner wall of the first chamber 62 adjacent to the planet carrier 3, when the planet carrier 3 rotates, it stirs the lubricating oil in the oil storage groove, and the lubricating oil enters the oil storage cavity 7 through the upper notch 52 above the outer wall of the annular oil baffle 5.

[0050] Since the size of the upper notch 52 is larger than that of the lower notch 53, most of the lubricating oil remains in the oil storage cavity 7, and a small part of the lubricating oil flows back to the oil storage groove through the lower notch 53 directly below the outer wall of the annular oil baffle 5.

[0051] The rotation of the planet carrier 3 continues to stir the lubricating oil that has flowed back into the oil storage groove. The lubricating oil that has flowed back into the oil storage groove enters the oil storage cavity 7 through the upper notch 52 above the outer wall of the annular oil baffle 5, and continues to repeat the process of flowing back to the oil storage groove through the lower notch 53.

[0052] In the embodiment of the present invention, the housing 6 is provided with a first chamber 62 and a second chamber 63 that are interconnected and connected to each other by a connecting wall 61. The diameter of the first chamber 62 is larger than that of the second chamber 63. The sun gear 1, multiple planetary gears 2, the planet carrier 3, the ring gear 4, and the annular oil baffle 5 are all installed in the first chamber 62. By providing the annular oil baffle 5, a gap between the annular oil baffle 5 and the connecting wall 61 forms the oil storage cavity 7. By providing the upper notch 52 and the lower notch 53 on the annular oil baffle 5, most of the lubricating oil remains in the oil storage cavity 7, and a small part of the lubricating oil flows back to the oil storage groove through the lower notch 53 directly below the outer wall of the annular oil baffle 5. Further, when the coaxial planetary gear reducer is working, the amount of lubricating oil in the oil storage groove stirred by the planet carrier 3 is reduced, so the churning loss is reduced. At the same time, the resistance of the lubricating oil to each component of the coaxial planetary gear reducer during movement is reduced, the working efficiency is improved, and the friction between each component of the coaxial planetary gear reducer and the lubricating oil is also reduced, and the heat generation of the coaxial planetary gear reducer is reduced.

[0053] Currently, the lubricating oil of the existing planetary gear reducer is stored below the housing, and the cooling oil passage of the cooling system is arranged at the bottom of the housing. When the planetary gear reducer is working, the planet carrier of the planetary gear reducer rotates and stirs the lubricating oil below the housing, causing the lubricating oil to splash. Therefore, there is less lubricating oil remaining below the housing, so that the cooling oil passage can contact less lubricating oil through the housing, and the heat exchange efficiency is low, resulting in poor cooling effect.

[0054] See Figure 5 and Figure 6 , Figure 5 which is a schematic structural diagram of the housing 6 provided by the embodiment of the present invention from another angle, Figure 6The schematic diagram of the structure of the cooling oil channel provided in the embodiment of the present invention is that in order to avoid the above-mentioned poor cooling effect, a cooling oil channel 8 is provided on the outer side of the connecting wall 61, wherein: Figure 6 The rightward arrow in the middle indicates that the lubricating oil in the first chamber 62 can enter the oil storage cavity 7 from above the annular oil baffle plate 5, and the leftward arrow indicates that the lubricating oil in the oil storage cavity 7 can flow back to the first chamber 62 from below the annular oil baffle plate 5.

[0055] Since the gap between the annular oil baffle plate 5 and the connecting wall 61 forms the oil storage cavity 7, and the cooling oil channel 8 is arranged on the outside of the connecting wall 61, the cooling oil channel 8 is close to the oil storage cavity 7. Figure 6 It can be seen that there is a connecting wall 61 between the cooling oil passage 8 and the oil storage cavity 7. Also, since most of the lubricating oil remains in the oil storage cavity 7 when the coaxial planetary gear reducer is working, and the lubricating oil in the oil storage cavity 7 will not splash around, the cooling oil passage 8 can contact more lubricating oil in the oil storage cavity 7 through the connecting wall 61, thereby improving the heat exchange efficiency and further improving the cooling effect.

[0056] When the existing planetary gear reducer is working, the planet carrier rotates and stirs the lubricating oil under the housing, causing the lubricating oil to splash, resulting in the lubricating oil quickly flowing to the position of the vent plug, causing the vent plug to leak oil, seriously affecting the operation of the planetary gear reducer.

[0057] Continue to see Figure 5 In order to avoid the above-mentioned oil leakage of the vent plug, the embodiment of the present invention further provides a vent plug 9, and a vent hole is provided above the inner wall of the first chamber 62 near the oil storage cavity 7, and the position of the vent hole is far away from the upper notch 52, and the vent plug 9 is installed in the vent hole.

[0058] When the coaxial planetary gear reducer is working, the planet carrier 3 rotates to stir the lubricating oil in the oil storage tank, so the flow speed of the lubricating oil in the oil storage cavity 7 is relatively low, and the position of the vent hole is far away from the upper notch 52. Therefore, the lubricating oil is not easy to leak from the vent plug 9, reducing the probability of oil leakage from the vent plug.

[0059] Continue to see Figure 1 and see Figure 3 The coaxial planetary gear reducer provided in the embodiment of the present invention may further include a tapered roller bearing 10. The power output shaft is installed in the second chamber 63 through the tapered roller bearing 10. An oil supply passage 11 leading to the tapered roller bearing 10 is provided on the inner side of the connecting wall 61.

[0060] Since an oil supply oil passage 11 leading to the tapered roller bearing 10 is provided inside the connecting wall 61, when the coaxial planetary gear reducer is working, the lubricating oil in the oil storage cavity 7 can be transported to the tapered roller bearing 10 along the oil supply oil passage 11 to ensure the normal operation of the tapered roller bearing 10.

[0061] Those of ordinary skill in the art can understand that: The drawings are only schematic diagrams of an embodiment, and the modules or processes in the drawings are not necessarily essential for implementing the present invention.

[0062] Those of ordinary skill in the art can understand that: The modules in the device in the embodiment can be distributed in the device of the embodiment according to the description of the embodiment, or can be correspondingly changed and located in one or more devices different from this embodiment. The modules of the above embodiments can be combined into one module, or can be further split into multiple sub-modules.

[0063] Finally, it should be noted that: The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: They can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A coaxial planetary gear reducer with shell cooling, characterized in that, It includes a sun gear, multiple planetary gears, a planet carrier, a ring gear, an annular oil baffle, and a housing; The housing includes a first chamber and a second chamber that are interconnected and connected to each other by a connecting wall. The diameter of the first chamber is larger than that of the second chamber. The sun gear, the planet carrier, the ring gear, and the annular oil baffle are coaxial. The axis of each planetary gear is parallel to the axis of the sun gear, and the sun gear, the multiple planetary gears, the planet carrier, the ring gear, and the annular oil baffle are all installed in the first chamber; The power input shaft is connected to the sun gear. The sun gear is externally meshed with the multiple planetary gears. The multiple planetary gears are drivingly connected to the planet carrier. The planet carrier is connected to the power output shaft. The power output shaft is installed in the second chamber. The multiple planetary gears are internally meshed with the ring gear. The ring gear is fixedly installed on the inner wall of the first chamber. An oil storage groove for storing lubricating oil is provided below the inner wall of the first chamber and adjacent to the planet carrier; The annular oil baffle is sleeved on the planet carrier. The outer wall of the annular oil baffle is in clearance fit with the inner wall of the first chamber, and the annular oil baffle is fixedly connected to the inner side of the connecting wall. A storage oil cavity is formed by the gap between the annular oil baffle and the connecting wall. An upper notch is provided above the outer wall of the annular oil baffle, and a lower notch is provided directly below the outer wall of the annular oil baffle. The size of the upper notch is larger than that of the lower notch; A cooling oil passage is provided on the outer side of the connecting wall; It further includes a breather plug. An air vent is provided above the inner wall of the first chamber near the storage oil cavity, and the position of the air vent is far from the upper notch. The breather plug is installed in the air vent.

2. The speed reducer according to claim 1, characterized in that, It further includes a tapered roller bearing. The power output shaft is installed in the second chamber through the tapered roller bearing. An oil supply passage leading to the tapered roller bearing is provided on the inner side of the connecting wall.

3. The speed reducer according to claim 1, characterized in that, A protrusion is provided on the outer periphery of the ring gear, and a clamping groove is provided on the inner wall of the first chamber. The ring gear is clamped into the clamping groove through the protrusion.

4. The speed reducer according to claim 1, characterized in that, A plurality of first bolt holes with raised portions spaced circumferentially around the center are provided on the inner side of the connecting wall. The annular oil baffle is provided with a plurality of second bolt holes spaced circumferentially around the center. The first bolt holes and the second bolt holes are connected by bolts.

5. The speed reducer according to claim 1, wherein The planet carrier includes a plurality of mounting shafts. The axis of each mounting shaft is parallel to the axis of the sun gear. The multiple planetary gears are respectively installed on the plurality of mounting shafts through bearings. Among them, the number of mounting shafts is the same as the number of planetary gears.

6. The speed reducer according to claim 1, wherein The number of the planetary gears is three.

7. The speed reducer according to claim 1, characterized in that, The number of the upper notches is four, and the number of the lower notches is one.

8. The speed reducer according to claim 1, wherein The planet carrier and the power output shaft are integrally formed.

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