JP4750371B2 - Decelerator - Google Patents

Description

  The present invention relates to a speed reducer, and more particularly to a speed reducer having cooling fins.

  For example, in a reduction gear for driving a cooling fan or the like of a cooling tower, the heat load on the installation environment is high. Even without such a special installation environment, for example, a reduction gear that is continuously operated often has a severe heat load state particularly in summer.

  For a reduction gear used in such applications, for example, in Patent Document 1, a cooling structure in which a cooling fan is provided in the reduction gear is proposed. As shown in FIG. 6, the cooling fan 2 is integrally attached to the input shaft 3 rotating at a high speed in order to obtain a corresponding rotational speed. Further, the speed reducer 4 is provided with an oil pump 5 so that each part in the casing 6 can be cooled by circulating lubricating oil in the casing 6. The speed reducer 4 itself is a parallel axis type helical two-stage speed reducer having an intermediate shaft 7 and an output shaft 8 in addition to the input shaft 3.

  On the other hand, Patent Document 2 discloses a structure in which the cooling fan is cooled by directly applying air from a cooling fan to a so-called oil cooler unit with fins (lubricating oil cooling device in the lubricating oil passage). ing. Patent Document 2 further proposes a cooling structure in which a fan cover having a spiral protrusion on the inner periphery thereof is provided at an outer position of the cooling fan. The fan cover is provided with a discharge port, and an air passage through which air generated by the cooling fan passes is formed between the discharge port and the lubricating oil passage.

JP 2003-322224 A JP-A-8-105521

  However, the cooling method in which a cooling fan is attached to the speed reducer as in Patent Document 1 tries to cool the entire casing of the speed reducer with a large volume, so that the temperature reduction effect is low.

  In addition, a speed reducer equipped with an oil cooler unit as in Patent Document 2 can lower the temperature of the lubricating oil itself, so that it can be expected to have a corresponding cooling effect, but is expensive and complicated. Moreover, since the size and weight of the entire speed reducer also increase, a wider installation place is required.

  The present invention has been made in order to solve such a conventional problem, and has a simple structure, is inexpensive, and can reduce the speed at which the heat load is most likely to be efficiently cooled. The challenge is to provide a machine.

The present invention, reduction gear casing having a bearing supporting the gear shaft, a bearing casing for accommodating the casing surface or et collision out formed the bearing of teeth around the axle of the casing surface of the gear shaft extends through And cooling fins that are disposed on the outer surface of the bearing casing portion of the reduction gear casing and cool the bearing casing portion , and at least a part of the cooling fins is detachable, It solves the problem.

  In the present invention, attention is paid to the fact that the portion that really requires cooling does not occur evenly in the entire speed reducer, and the bearing portion of the gear shaft (for example, the input shaft) that requires cooling is accommodated. The bearing casing portion to be protruded from the casing surface is formed, and cooling fins are arranged on the protruding and formed bearing casing portion.

  Therefore, most of the bearing portion is surrounded by a dedicated bearing casing portion, and the wide outer surface of the bearing casing portion can effectively contribute to heat dissipation. And since the cooling fin is arrange | positioned in the said casing part using this wide outer side surface, the heat | fever dissipation can be performed very efficiently using the large surface area of a cooling fin.

  The intended cooling can be realized with a simple configuration and without reducing the original transmission torque of the reduction gear.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a sectional view of a speed reducer to which an embodiment of the present invention is applied, and FIG. 2 is a plan view thereof.

  The reduction gear 10 is a parallel shaft type two-stage reduction gear using a helical gear, and is used by being connected to a motor (not shown). The speed reducer 10 includes gear shafts of an intermediate shaft 16 and an output shaft 18 in addition to an input shaft 14 that receives power from a motor via a key 12.

  The input shaft 14 is supported by a pair of bearings 20 and 22 and a first helical pinion 24 is mounted. The intermediate shaft 16 is supported by bearings 26 and 28, and a first helical gear 30 and a second helical pinion 32 that mesh with the first helical pinion 24 are mounted. The output shaft 18 is supported by bearings 34 and 36, and an output gear 38 that meshes with the second helical pinion 32 on the intermediate shaft 16 is mounted. Each of the bearings 20, 22, 26, 28, 34, and 36 is a tapered roller in order to receive an axial load applied to each gear shaft (14, 16, 18) due to rotation of a helical pinion or a helical gear. It is a type bearing. Of the pair of bearings 20 and 22 that support the input shaft 14, the motor-side bearing 20 is a bidirectional type that can receive an axial load in both directions by itself.

  The input shaft 14 rotates at a high speed, a temperature rise due to friction in the bearings 20 and 22 is large, and the input shaft 14 is placed in a severe state due to heat load.

  Therefore, in this embodiment, the present invention is applied to the vicinity of the motor-side bearing 20 among the pair of bearings 20 and 22 that support the input shaft (gear shaft) 14. More specifically, the bearing 20 (at least half of the bearing 20) is disposed outside the basic center line (center line ignoring small protrusions) L1 in the vicinity of the input shaft 14 of the casing 40 of the speed reducer 10. .

  On the other hand, the casing 40 of the speed reducer 10 has a bearing casing portion 44 that houses the bearing 20. The bearing casing portion 44 corresponds to an outer shift of the bearing 20 and is formed in a state of protruding from the casing surface 40A1 in the vicinity of the input shaft 14 in the casing surface 40A through which the input shaft 14 passes. An oil seal 48 is mounted between the front end of the bearing casing portion 44 and the input shaft 14 so that the airtightness inside and outside the casing 40 is maintained.

  As shown in FIG. 3, a part of the outer surface 44 </ b> A of the bearing casing portion 44 is cut in parallel to the vertical direction to form a pair of flat surface portions 50 (50 </ b> A, 50 </ b> B). Cooling fins 52 (52A, 52B) are detachably attached to the flat portion 50 by means such as bolts (not shown).

  Although not depicted in FIG. 3, as shown in FIGS. 1 and 2, a cooling fan mounting member 54 is press-fitted or attached to the input shaft 14 by a bolt (not shown). A cooling fan 58 is attached to the cooling fan attachment member 54 via the via.

  In addition, a fan cover 60 that covers the cooling fan 58 together with the bearing casing portion 44 and the cooling fins 52 is attached to the casing 40 of the speed reducer 10 by bolts (not shown) or the like. A part of the fan cover 60 extends through the side surface 40B of the casing 40 of the speed reducer 10 to the side opposite to the motor of the speed reducer 10, and is formed between the side surface 40B and the back surface 40C of the casing 40. The vicinity of the bearing 22 on the non-motor side of the input shaft 14 can also be cooled via the air passage 62.

  Next, the operation of the speed reducer 10 according to this embodiment will be described.

  When a motor shaft of a motor (not shown) rotates, the input shaft 14 connected to the motor shaft via the key 12 rotates. When the input shaft 14 rotates, the intermediate shaft 16 rotates through the engagement of the first helical pinion 24 and the first helical gear 30, and further, the output shaft 18 rotates through the engagement of the second helical pinion 32 and the output gear 38. To do.

  At this time, the cooling fan 58 rotates integrally with the input shaft 14 as the input shaft 14 rotates, and supplies cooling air to the bearing casing portion 44 of the casing 40. Since the bearing casing portion 44 protrudes from the casing surface 40A1 in the vicinity of the input shaft 14 of the casing 40, the surface area thereof is large. Moreover, since the pair of cooling fins 52 (52A, 52B) are attached to the outer surface 44A (specifically, the flat surface portion 50) of the bearing casing portion 44, a very large heat radiation area in the vicinity of the bearing 20 is ensured. Therefore, the heat in the vicinity of the bearing 20 is radiated efficiently.

  Furthermore, since the cooling fan 58 always carries away the warmed air in the vicinity of the cooling fins 52 to other places, the cooling fins 52 are continuously supplied with cold air that is more easily heat-exchanged. Thus, heat dissipation is further promoted. Since the air flow by the cooling fan 58 is guided along the side surface 40C and the back surface portion 42C of the casing 40 without being unnecessarily diffused by the fan cover 60, the side surface 40B and the back surface 40C of the casing 40, particularly its The vicinity of the bearing 22 on the non-motor side of the input shaft 14 is also efficiently cooled.

  Further, a flat surface portion 50 is formed on the outer surface 44 </ b> A of the bearing casing portion 44, and the cooling fins 52 are detachably disposed on the flat surface portion 152. Therefore, when the environment changes, depending on the application, for example, the cooling fin 52 is replaced with a larger one, or only one side (for example, only the right cooling fin 52A in FIG. 3) is attached due to the installation location. It can also be used with a large degree of freedom in mounting.

  In the above-described embodiment, the two-stage parallel shaft type speed reducer 10 having the helical gear set is shown, but the speed reducer according to the present invention is not particularly limited. For example, as shown in FIGS. 4 and 5, in addition to the gear shaft 114 (in this case, the input shaft) 114 to be cooled, a gear shaft orthogonal to the gear shaft (in this embodiment, the intermediate shaft 116 and the output shaft 118). The effect of the present invention can be obtained in a similar manner even with a so-called quadrature reduction gear. That is, in this embodiment, a bevel pinion 124 is provided at the tip of the input shaft 114, and a bevel gear 130 that meshes with the bevel pinion 124 is attached to the intermediate shaft 116.

  However, also in this embodiment, the bearing 120 on the motor (not shown) side of the input shaft 114 is disposed outside the basic center line L2 near the input shaft 114 in the casing 140 of the speed reducer 110. Correspondingly, the bearing casing portion 144 protrudes from the casing surface 140A1 in the vicinity of the input shaft 114 of the casing surface 140A through which the input shaft 114 passes. Cooling fins 152 (152A, 152B) are attached to the outer surface 144A of the bearing casing 144. Therefore, also in this embodiment, efficient cooling can be performed by the synergistic effect of the protrusion of the bearing casing portion 144 and the arrangement of the cooling fins 152.

  In this embodiment as well, the speed reducer 110 is provided with a cooling fan 158 and a fan cover 160. However, in this embodiment, considering that the casing 140 of the speed reducer 110 is long in the axial direction of the input shaft 114, the fan cover 160 forms a ring-shaped opening 160A on the non-motor side of the fan cover 160, The entire casing 140 of the speed reducer 110 is designed to be cooled through the opening 160A.

  Other configurations are almost the same as those in the previous embodiment, and therefore, in the figure, the parts having the same functions are decremented by the same reference numerals, and redundant description is omitted.

  In the above embodiment, the input shaft is selected as the gear shaft to which the cooling fins 152 and the cooling fan 158 are attached. However, in the present invention, the gear shaft to be attached is not particularly limited to the input shaft. For example, if the vicinity of the gear shaft other than the input shaft such as the intermediate shaft and the output shaft is required to be cooled in relation to the installation location, the gear shaft bearing is accommodated instead of the input shaft or together with the input shaft. The bearing casing portion may be protruded from the surface of the casing surface in the vicinity thereof. The present invention may be applied only to a gear shaft other than the input shaft, or the present invention may be applied to both bearings of a specific gear shaft. In any case, the vicinity of the bearing of the gear shaft can be efficiently cooled as in the previous embodiment by attaching a cooling fin to the outer surface of the projected bearing casing portion.

  Moreover, in the said embodiment, although the cooling fan was further provided, this invention does not necessarily require the attachment of a cooling fan. This is because sufficient cooling is often possible only by the protrusion of the bearing casing portion and the attachment of the cooling fins. If the cooling fan is not installed, noise can be further reduced and the original transmission torque does not need to be reduced. Therefore, it is preferable not to install the cooling fan unless it is used under particularly high heat load conditions. There are many things.

  Further, in the present invention, a flat portion is provided on a part of the outer surface of the bearing casing portion, and consideration has been given so that the cooling fin can be easily attached using this flat portion. However, the formation of the flat portion is not necessarily required. Not necessary.

  The present invention is applicable to a reduction gear used under severe heat load environments or operating conditions.

The top view of the reduction gear to which an example of embodiment concerning the present invention was applied Sectional view View of arrow III in FIGS. 1 and 2 showing the vicinity of the cooling fin The top view of the reduction gear which concerns on an example of embodiment of this invention Sectional view Sectional view showing an example of a conventional speed reducer considering the cooling function

Explanation of symbols

10 ... Reducer 14 ... Input shaft (gear shaft)
16 ... Intermediate shaft (gear shaft)
18 ... Output shaft (gear shaft)
20, 22, 26, 28, 34, 36 ... Bearing 40 ... Casing 40A ... Casing surface 40A1 ... Surface 42A ... Surface 44 ... Bearing casing portion 44A ... Outer surface 46 ... Side portion 48 ... Back portion 50 ... Plane portion 52 ... Cooling Fin 54 ... Cooling fan mounting member 58 ... Cooling fan 60 ... Fan cover 62 ... Air path L1 ... Basic center line

Claims (6)

A bearing that supports the gear shaft;
A reduction gear casing having a bearing casing portion that is formed to project from a casing surface in the vicinity of the gear shaft in a casing surface through which the gear shaft passes;
A cooling fin disposed on an outer surface of the bearing casing portion of the reduction gear casing and cooling the bearing casing portion ;
With
A speed reducer in which at least a part of the cooling fin is detachable. In claim 1,
A speed reducer having a plurality of the cooling fins and detachable individually . In claim 1 or 2,
A reduction gear provided with a cooling fan at a position where the cooling air can be supplied to the bearing casing portion of the gear shaft. In claim 3 , further:
A fan cover for guiding wind generated by the cooling fan ;
The gear shaft is supported by a bearing of the bearing casing portion and a bearing different from the bearing,
The speed reducer in which the fan cover extends to the other bearing side through a side surface of the speed reducer. In any one of Claims 1-4 ,
A part of the outer surface of the bearing casing part comprises a flat part,
A speed reducer in which the cooling fin is disposed on the flat portion. In any one of Claims 1-5,
The speed reducer includes another gear shaft that is orthogonal to the gear shaft.

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