JP2011190909A - Reduction gear - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a reduction gear from being increased in size (structure in which an air bleeder projects to the side of a speed reducer) while preventing a lubricating oil from leaking out by preventing the pressure inside the speed reducer from rising. <P>SOLUTION: This reduction gear 100 includes the speed reducer 104, a motor 102, and an inhibiting structure 106 which is disposed between the motor 102 and the speed reducer 104 and which inhibits the entry of the lubricating oil Oi sealed in the inner space 107 of the speed reducer 104 to the motor 102 side. The motor shaft 103 of the motor 102 or a shaft rotating integrally with the motor shaft 103 configures a hollow shaft 108 having a hollow part 108A. The hollow shaft 108 includes a first opening 108B opening further on the speed reducer 104 side than the inhibiting structure 106, and a second opening 108C opening further on the anti-speed reducer side than the inhibiting structure 106 to discharge the air in the hollow part 108A. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a reduction gear.

  Patent Document 1 discloses a vertical rotating electrical machine (decelerator) as shown in FIG.

  When the vertical rotary electric machine is installed in such a manner that the motor is arranged on the upper side of the speed reducer, it lubricates the high-speed gear that is located on the upper side of the speed reducer. Oil must be enclosed. For this reason, the amount of lubricating oil enclosed with respect to the volume of the middle space of the reduction gear tends to increase (the air space decreases). As a result, when the temperature of the speed reducer rises, the pressure inside the speed reducer tends to rise, and the problem of lubricating oil leaking from the oil seal portion tends to occur.

  In order to cope with this problem, the vertical rotary electric machine 2 of Patent Document 1 is provided with an air vent device 1 separately.

  The air vent device 1 includes an air vent pipe 4 connected to a side portion of the rotating electrical machine main body 6 and an air breather 5 connected to the tip of the air vent pipe 4. When the internal pressure in the oil tank 3 rises, the air in the oil tank 3 is discharged from the air breather 5 through the air vent pipe 4. With this mechanism, the air vent device 1 prevents the internal pressure of the oil tank 3 of the rotating electrical machine 2 from rising excessively.

1-76163 (Fig. 1)

  However, the conventional rotating electrical machine (decelerator) 2 is configured to separately attach the air vent device 1 to the side of the rotating electrical machine main body 6 in order to reduce the internal pressure of its own oil tank 3. For this reason, the number of parts of the rotating electrical machine 2 itself increases, and the air vent device 1 requires a space radially outward from the outer shape of the rotating electrical machine main body 6. As a result, the rotating electrical machine 2 itself becomes large. At the same time, there was a risk of interference with peripheral equipment.

  The present invention has been made to solve the above-described problem, and prevents the lubricating oil from leaking by preventing an increase in the pressure inside the speed reducer, while increasing the size of the speed reducer (the air venting device reduces the speed). It is an object to prevent the structure protruding to the side of the machine).

  The present invention includes a speed reducer, a motor, and a blocking structure that is disposed between the motor and the speed reducer and prevents lubricating oil enclosed in the internal space of the speed reducer from entering the motor side, The motor shaft of the motor or a shaft that rotates integrally with the motor shaft constitutes a hollow shaft having a hollow portion, and the hollow shaft has the speed reducer more than the blocking structure. The above problem has been solved by a configuration including a first opening that opens on the side and a second opening that opens on the side opposite to the speed reducer than the blocking structure and can discharge the air in the hollow portion.

  In the present invention, the motor shaft or the shaft that rotates integrally with the motor shaft constitutes a hollow shaft having a hollow portion, and the hollow shaft prevents the lubricating oil from entering the motor side. A first opening portion is provided on the speed reducer side and a second opening portion is provided on the counter speed reducer side, with the arrangement position as a boundary. With this configuration, the internal space of the speed reducer can communicate with the space outside the speed reducer via the first opening and the second opening of the hollow shaft, and an increase in the internal pressure of the speed reducer can be prevented. As a result, the air venting device or the like does not protrude to the side of the speed reducer, so that interference with peripheral devices can be prevented and an increase in the size of the speed reducer can be prevented.

  According to the present invention, it is possible to prevent an increase in the size of the reduction gear (a structure in which the air vent device protrudes to the side of the reduction gear) while preventing leakage of lubricating oil by preventing an increase in pressure inside the reduction gear. it can.

The longitudinal cross-sectional view of the reduction gear device concerning an example of embodiment of this invention Enlarged view of the arrow II part of Fig. 1 Front view of an air vent device provided in a conventional rotating electric machine

  Hereinafter, a reduction gear 100 according to an example of an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a longitudinal sectional view of the speed reducer 100, and FIG. 2 shows an enlarged view of an arrow II portion of FIG.

  The upper side of each figure corresponds to the upper side when the speed reducer 100 is actually provided.

  The reduction gear 100 is a so-called vertical-type reduction gear that includes a motor 102 and a reduction gear 104 and arranges the motor 102 above the reduction gear 104. In the case of the vertical type reduction gear 100, the amount of the lubricating oil Oi enclosed with respect to the volume inside the reduction gear 104 tends to increase. For this reason, when the oil level of the lubricating oil Oi rises due to the operation of the speed reducer 100, the pressure inside the speed reducer 104 rises and the lubricating oil Oi may easily leak. In order to prevent this phenomenon, the speed reduction device 100 according to the present embodiment employs the following configuration.

  The speed reducer 104 includes an input shaft 105, external gears 122 and 124 that eccentrically swing around the input shaft 105, and an internal gear 126 that internally meshes while the external gears 122 and 124 swing eccentrically. And a bevel pinion 128 and a bevel gear 130.

  Further, the oil seals 106, 112, 114, 116, 118 and the O-rings 113, 115 prevent this lubricating oil Oi from leaking out of the speed reducer 104. Among these, the oil seal (blocking structure) 106 is disposed between the motor 102 and the speed reducer 104 (specifically, between the casing 110 of the speed reducer 104 and the motor shaft 103 of the motor 102). The lubricating oil Oi enclosed in the space 107 is prevented from entering the motor 102 side.

  The motor shaft 103 of the motor 102 passes through the motor 102 and extends to the inside of the speed reducer 104 (specifically, the side surface of the external gear 124 on the side opposite to the motor). The motor shaft 103 is integrated with the input shaft 105 of the speed reducer 104 and is also used. That is, the input shaft 105 rotates integrally with the motor shaft 103.

  The motor shaft 103 has a motor shaft hollow portion 103A. The input shaft 105 that rotates integrally with the motor shaft 103 has an input shaft hollow portion 105A that is continuous with the motor shaft hollow portion 103A. That is, the motor shaft 103 and the input shaft 105 of the speed reducer 104 that rotates integrally with the motor shaft 103 constitute a hollow shaft 108 having a hollow portion 108A composed of the motor shaft hollow portion 103A and the input shaft hollow portion 105A. Yes.

  The hollow shaft 108 includes a first opening 108 </ b> B that opens closer to the speed reducer 104 than the oil seal 106. Further, the hollow shaft 108 includes a second opening 108 </ b> C that is opened on the side opposite to the speed reducer than the oil seal 106 and can discharge the air in the hollow portion 108 </ b> A.

  In the present embodiment, the first opening 108B is merely an opening hole, and opens to the end 108T of the hollow shaft 108 on the speed reducer 104 side. On the other hand, the second opening 108 </ b> C is configured at the end 108 </ b> U of the hollow shaft 108 on the side opposite to the speed reducer.

  The second opening 108 </ b> C includes a filter-type air breather 120. The air breather 120 mainly includes an inner cap 120A, an outer cap 120B that covers the inner cap 120A, and a filter 120D. A channel 120C is formed inside the inner cap 120A and the outer cap 120B, and the hollow portion 108A and the outer space 121 are communicated. The filter 120D is disposed on the flow path 120C. The filter 120D is made of an oil-repellent polyester nonwoven fabric having fine holes with a diameter that allows the air in the hollow portion 108A to be freely discharged but does not allow the lubricating oil Oi to pass through.

  The second opening 108C also serves as an oil supply port for supplying the lubricating oil Oi to the internal space 107 of the speed reducer 104. The filter-type air breather 120 is removed from the hollow shaft 108 (when the operation of the speed reduction device 100 is stopped), and lubricating oil Oi is supplied from the second opening 108C. Although the speed reduction device 100 has a simple configuration in which a dedicated oil supply port is not separately provided, the supply operation of the lubricating oil Oi can be realized through the second opening 108C.

  Next, the operation of the speed reducer 100 centering on the oil seal 106, the hollow shaft 108, etc. will be described.

  For example, due to the operation of the speed reducer 100 described above (e.g., the corresponding volume inside the speed reducer 104 decreases or bubbles are generated in the lubricating oil Oi), the oil level of the lubricating oil Oi rises, and the speed reducer 104 The internal pressure may increase. In this case, the lubricating oil Oi sealed in the internal space 107 of the speed reducer 104 can move from the first opening 108B into the hollow portion 108A of the hollow shaft 108. Even if the lubricating oil Oi moves, the filter 120D of the filter type air breather 120 discharges air in the hollow portion 108A from the second opening portion 108C to the external space 121. Can be prevented from rising. Since the fine holes of the filter 120D prevent the passage of the lubricating oil Oi composed of particles larger than its own diameter, the lubricating oil Oi is prevented from leaking from the second opening 108C to the external space 121. it can. In addition, since the outer cap 120B covers the outside of the filter 120D, dust, dust, and the like are prevented from entering from the second opening 108C.

  As a result, the oil seals 106, 112, 114, 116, 118 and the O-rings 113, 115 can satisfactorily hold the lubricating oil Oi in the internal space 107.

  Since the hollow shaft 108 is a component that is originally provided in the speed reducer 100, the number of components added to prevent an increase in internal pressure can be reduced. Further, the air venting device or the like does not protrude in the radial direction of the speed reduction device 100, and interference between the speed reduction device 100 and peripheral devices can be prevented. As a result, the hollow shaft 108 can reduce the number of parts of the reduction gear 100 itself, and can effectively reduce the internal pressure while reducing the size, weight and cost of the reduction gear 100 itself. Can be achieved.

  Since the hollow shaft 108 serves as the motor shaft 103 of the motor 102 and the input shaft 105 of the speed reducer 104, the lubricating oil Oi inside the speed reducer 104 is (first and second openings 108B, 108C). The hollow shaft 108 can reliably hold the lubricating oil Oi in the hollow portion 108A without leaking from the middle of the hollow portion 108A in the axial direction to the motor 102 side.

  As another embodiment, it is beneficial to configure so that the second opening of the hollow shaft can be completely closed. For example, a plug can be attached to the second opening (in exchange for a filter type air breather) so that the second opening can be completely closed. With this configuration, when the speed reducer is arranged in a form other than “vertically placed”, for example, when the motor and the speed reducer are arranged horizontally with respect to the ground, Even when it is used at a predetermined angle, it is possible to completely prevent the lubricating oil enclosed in the reduction gear from leaking through the hollow shaft. In such an arrangement, the reduction gear needs only to be filled with lubricating oil to a level slightly above the shaft center of the reduction gear. However, there is no problem of entering the motor side beyond the blocking structure. That is, with this configuration, the speed reducer can be freely arranged and used in either “vertical” or “horizontal” positions.

  In addition, like the speed reducer according to the above-described embodiment, when the first opening of the hollow shaft is invaded by the lubricating oil inside the speed reducer, the lubricating oil enters the hollow portion from the first opening of the hollow shaft. However, when the first opening is not immersed in the lubricating oil, the air inside the speed reducer enters the hollow shaft. Even in this case, the effect of preventing an increase in internal pressure in the internal space of the reduction gear can be obtained in the same manner as described above.

  In addition, the configuration that allows air to pass through the second opening such as the cap mechanism is not limited to the configuration in which the filter-type air breather is disposed. For example, the air pressure in the hollow portion is greater than or equal to a predetermined level. A pressure adjustment type air breather that discharges air in the hollow shaft and the like may be disposed. The configuration in which the air is discharged only after the pressure in the hollow portion reaches a predetermined value or higher enables a stronger occlusion at a level where the internal pressure does not cause a problem, so that the effect of preventing leakage of the lubricating oil can be further enhanced.

  The hollow shaft does not necessarily have to serve as both the motor shaft and the input shaft of the speed reducer. The motor shaft and the input shaft of the speed reducer are configured separately, and are connected by, for example, a coupling, etc. A rotating hollow shaft may be configured.

  Moreover, in the said embodiment, although the 2nd opening part serves also as a fueling port, it does not necessarily need to serve as a fueling port, for example, it comprises a separate dedicated fueling port in the casing, and decelerates from this fueling port. Lubricating oil may be supplied to the inside of the machine. In this case, since the fuel filler port can have a simple configuration, the maximum outer shape of the reduction gear is not increased.

  In the above embodiment, the oil seal is used as the blocking structure. However, the oil seal is not limited to the oil seal, and other members, structures, etc. may be used as long as the lubricating oil can be prevented from entering the motor side. Also good. For example, the labyrinth structure or the like may be used to prevent the lubricating oil from entering the motor side.

  Moreover, in the said embodiment, although the 1st, 2nd opening part of the hollow shaft was each formed in the end surface of a hollow shaft, it does not necessarily need to be an end surface, for example, the 1st, 2nd opening You may make it form a part in the side surface of the radial direction of a hollow shaft.

  The type of the speed reducer when applying the present invention is not limited to the swing inscribed meshing speed reducer according to the above embodiment. For example, the present invention can also be applied to a reduction gear that employs a simple planetary gear type reduction gear, a reduction gear using a parallel shaft gear, or the like.

DESCRIPTION OF SYMBOLS 100 ... Reduction gear 102 ... Motor 103 ... Motor shaft 104 ... Reduction gear 105 ... Input shaft 106 ... Blocking structure 107 ... Internal space (of reduction gear) 108 ... Hollow shaft 108A ... Hollow portion 108B ... First opening 108C ... First 2 openings Oi ... Lubricating oil

Claims (6)

A speed reducer comprising: a speed reducer; a motor; and a blocking structure that is disposed between the motor and the speed reducer and prevents the lubricating oil sealed in the internal space of the speed reducer from entering the motor side. In the device
The motor shaft of the motor or the shaft that rotates integrally with the motor shaft constitutes a hollow shaft having a hollow portion,
The hollow shaft includes a first opening that opens on the speed reducer side with respect to the blocking structure, and a second opening that is open on the side opposite the speed reducer with respect to the blocking structure to discharge air in the hollow portion. A speed reducer comprising the opening. In claim 1,
A filter type air breather having a filter that allows air to pass but does not allow lubricating oil to pass therethrough is disposed in the second opening. In claim 1,
A pressure adjustment type air breather is disposed in the second opening to discharge the air in the hollow shaft by opening the air in the hollow with a pressure of a predetermined magnitude or more. Characteristic reduction gear. In any one of Claims 1-3,
The speed reduction device, wherein the second opening is configured to be able to be completely closed. In any one of Claims 1-4,
The second opening portion also serves as an oil supply port for supplying the lubricating oil to the internal space of the speed reducer. In any one of Claims 1-5,
The speed reducing device, wherein the hollow shaft serves as a motor shaft of the motor and an input shaft of the speed reducer.

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