JP2003222229A - Gear driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gear driving device which facilitates machinability and increases a seal function in a power transmission part, and has an appropriate constitution. <P>SOLUTION: This gear driving device 1 in which a planetary gear mechanism 10 is assembled is constituted in such a way that an inner ring 19a of a support bearing 19 of a shaft body (input shaft 15) connected with a carrier 11 of a planetary gear directly and protruding to the outside of a casing 2 is extended on an outer side to be longer than a bearing width and an oil seal 21 mounted on a bearing housing is brought into contact with a peripheral face of an extension part 19a' of the inner ring. Moreover, a sun gear 16 meshing with the planetary gear 13 is inserted from the inside of the input shaft 15 of the carrier 11, one end of a sun gear support shaft 16a is fitted in and supported on a boss part of the gear 31 at a second step, and a center part is supported by a holder 27 in which a tip of the sun gear support shaft 16a is detachably attached to the inside of the input shaft 15. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-output gear acceleration / deceleration drive mechanism, and in particular, an assembly of a bearing portion and a planetary gear structure on an input side (output side when decelerating) for increasing output. The present invention relates to a gear drive device having ease.

[0002]

2. Description of the Related Art Generally, in a gear device that obtains a high output, for example, a gear device (gearbox) that outputs a high output at a high speed, the input shaft portion thereof receives a higher torque than the final output shaft portion and rotates. Therefore, the planetary gear mechanism is used to make the device compact. Usually, in this type of gearbox, a low-speed carrier equipped with a planetary gear is directly connected to its input portion, and a plurality of planetary gears supported by the carrier are formed on the inner peripheral surface of the casing. And the sun gear provided on the same axis as the input shaft engages to increase the speed of the second stage, and the rotation is sequentially transmitted from the gear attached to the sun gear shaft to the next speed increasing gear train. The desired high speed rotation is obtained and output.

An oil seal, a dust seal, a labyrinth seal or a mechanical seal is always provided on the outer side of the bearing provided in the casing of the gear drive device to prevent foreign matter from entering the bearing portion from the outside and from the inside. It is designed to prevent the lubricant (oil) from leaking.

[0004]

However, when a large power transmission element is attached to the input shaft or the output shaft of the gear drive device, for example, the sealing element (dust seal or oil seal) provided outside the bearing portion is
In many cases, it is not possible to easily remove the large power transmission element on the shaft located on the outside thereof, so if the sealing element is damaged, the operation of the gear drive device will be abnormal and this gear drive device will be the main part. In the case of equipment (device), there is a problem of causing a serious accident.

From the above, in the mounting portion of the seal element, the surface of the outer peripheral surface of the rotary shaft is processed more precisely to improve the surface accuracy, and the contact condition with the seal element is stabilized, and It is necessary to increase the surface hardness in order to extend the life. However, in a large gear drive device, particularly in a device that employs a planetary gear mechanism, the carrier arranged as the low speed stage is a cast product because of its structure. It is very difficult to make the contact portion of the lip of the seal element, which comes into contact with the input shaft (output shaft in the case of a speed reducer) integrated with the above, correspond with high accuracy in terms of work. In addition, even if it is possible to finish with high precision on the work, it is necessary to perform treatments such as induction hardening and nitriding in order to make the surface hardness of the sliding part hard, which increases the number of processing steps and increases the manufacturing cost. The problem arises. In other words, when the carrier is made of cast steel, it is difficult to avoid the occurrence of cavities if it is a large product due to its shape, and it is not possible to identify the location where it occurs, so it is safe to use. Causes problems.

On the other hand, when the carrier is made of cast iron, the flowability of the molten metal is better than that of cast steel, so that the formation of cavities can be avoided and the carrier having a complicated shape can be easily formed. It can be obtained, and safety can be ensured even in use. However, in the case of this cast iron, there arises a problem that the surface roughness of the outer peripheral surface of the input shaft portion cannot be finished to be equal to that of the cast steel product.

On the other hand, in the gear drive device adopting this type of planetary gear mechanism, it is required that the assembling structure can be rationalized, and in particular, as the size increases, the combination structure of the carrier of the planetary gear and the sun gear is increased. Rationalization of will affect accuracy.

The present invention has been made in view of the above-mentioned problems, and provides a gear drive device having a purposeful structure, which facilitates workability and enhances a sealing function in a power transmission portion. The purpose is to do.

[0009]

In order to achieve the above-mentioned object, the gear drive according to the first aspect of the present invention is a gear drive in which a planetary gear mechanism is incorporated, and is directly connected to a carrier of a planetary gear. The inner ring of the support bearing of the shaft body protruding outside the casing is extended to the outside longer than the bearing width, and the seal ring mounted on the bearing housing is brought into contact with the outer peripheral surface of the inner ring extension. It is characterized by that.

According to the present invention, the seal portion provided outside the bearing portion that supports the low speed side shaft body of the carrier of the integrally formed planetary gear, which is projected to the outside of the casing for transmitting power, By making the inner ring of the bearing longer than the bearing width and contacting the outer peripheral surface extended outward, the function of oil seal or dust seal can be achieved by using a member with high dimensional accuracy. As a result, the problem of the low-speed-side shaft body of the carrier, which is difficult for the surface accuracy in processing to satisfy the sealing function, can be solved without difficulty, and the function of the bearing portion can be maintained. In addition, the surface hardening to improve the durability of the seal ring is originally a hardening treatment of the bearing itself, so it is not necessary to bother to increase the surface hardness of cast iron in a separate process (for example, the bearing inner ring). Has a hardness of H _{RC of} 65 or more, and when cast iron is induction hardened, the surface hardness is at most H _RC 58.) Furthermore, the durability of the seal ring can be enhanced, and the workability can be facilitated to reduce the cost.

In the present invention, a roller bearing is incorporated in the bearing portion, the inner ring of the bearing is extended outward by a required dimension, and the outer peripheral surface of the extended portion of the inner ring is mounted on the outer surface portion of the housing of the bearing. It is preferable that the seal ring fitted to the bearing pressing member is brought into contact with the bearing pressing member (second invention). By doing so, the outer peripheral surface of the inner ring of the bearing fitted and axially supported by the shaft portion integral with the carrier of the planetary gear can be the sealing surface by the seal ring, and a highly accurate contact surface can be easily obtained. It is possible to obtain the effect that the sealing effect can be enhanced.

According to a third aspect of the present invention, there is provided a gear drive device in which a planetary gear mechanism is incorporated, wherein the sun gear arranged inside the carrier of the planetary gear so as to mesh with the planetary gear is the carrier of the carrier. It is inserted from the inside of the low speed side hollow shaft, one end of the sun gear support shaft is fitted and supported by the boss portion of the gear of the second step, and the other end of the sun gear support shaft is detachably attached inside the low speed side hollow shaft. The center part is supported by the holder.

According to the present invention, when the planetary gear mechanism is assembled, the carrier of the planetary gear is assembled in the gear casing and then the sun gear is incorporated through the inside of the hollow shaft on the low speed side. Even if the device is large, the planet gear carrier, which is difficult to handle due to its weight, can be stored in the gear casing first, and then the lightweight sun gear can be assembled to the center of the gear casing. There is an advantage that productivity can be improved.

A float bearing is preferably arranged in the center portion of the holder for supporting one end of the sun gear support shaft in the third invention (fourth invention). In this way, even if a minute meshing error occurs when the sun gear and the planetary gear mesh with each other, the sun gear can be finely displaced correspondingly, and therefore it is possible to avoid the influence of the local load. Further, it is preferable that the holder also serves as a lid that closes the internal space of the planetary gear carrier (fifth invention). By doing so, one end of the sun gear support shaft is supported, and the inside of the casing of the gear drive device is closed via the planetary gear carrier to prevent foreign matter from entering and lubricating oil from leaking from the outside. .

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Next, specific embodiments of a gear drive device according to the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of the gear drive system of this embodiment.
A developed sectional view along the line A-A in FIG.
FIG. 2 is a right side view of FIG. 1, and FIG. 3 is a view showing a center part support structure of a sun gear support shaft. FIG. 2 is a support structure view using a ball (a) and a support structure diagram by a flat type sliding piece (b). Respectively indicated by.

Although not shown, the gear drive device 1 of this embodiment is a speed increaser used for increasing the rotational force from a wind turbine in a wind turbine generator and transmitting it to the generator.
The relationship with the windmill is omitted.

This gear drive device 1 is a machine body (not shown).
A casing 2 provided with a mounting portion mounted on the outside
Is composed of a front cover 2a constituting a main body portion, a casing body portion 2b having an internal gear formed on an inner periphery thereof, a rear casing 2c having a speed increasing gear train incorporated therein and a cover 2d thereof. The planetary gear mechanism 10 is arranged in the body portion 2b, and the speed increasing gear train 3 is arranged in the rear casing 2d.
The speed is increased by 0 and the output shaft 35 is connected to the connected power generator.

The planetary gear mechanism 10 is located inside the casing main body (body 2b) and is integrally formed with the input shaft 15 (corresponding to the shaft of the present invention or the low speed side hollow shaft) 11 A plurality of planet gears 13 (for example, three) that are rotatably supported by a shaft 12 on a circle drawn on the carrier 11 with a required radius, and fixed on the inner circumference of the casing body 2b. Internal gear 14 and the carrier 1
1 and a sun gear 16 located coaxially inside the planetary gear 13 and the planetary gear 13 having the required gear ratio.
The sun gear 16 meshes with the sun gear 16 to make a planetary motion, and the sun gear support shaft 16a is accelerated to transmit power to the speed increasing gear train 30 arranged in the rear casing 2c.

The carrier 11 is supported by a roller bearing 19 that allows one integral input shaft 15 to be loaded into a bearing housing 18 provided in the central portion of the casing front cover 2a, and the other shaft portion 15 'to the rear casing. It is supported by the bearing portion 17 provided in 2c,
It is rotatably supported. Further, the input shaft 15 is formed as a hollow shaft, and a mounting seat portion 26 of a holder 27 described later is provided therein. The carrier 11 is made of cast iron.

In the bearing portion that supports the input shaft 15 of the carrier 11, the inner ring 19a of the roller bearing 19 that directly supports the input shaft 15 is replaced by the bearing 19 thereof.
Is made longer than the width of the inner ring extension 19
a'is projected toward the outside of the bearing housing 18, and the lip portion of the oil seal 21 fitted into the inner diameter portion of the bearing retainer 20 fitted and inserted into the bearing housing 18 from the outside is the bearing inner ring extension portion. It is configured to contact and seal the outer peripheral surface of 19a. In the gear drive device of this embodiment, the interior of the gear drive unit is lubricated with an oil bath.

In the gear drive device 1 (gearbox) of the present embodiment thus configured, when the input shaft 15 connected to the wind turbine rotates, the planet gear carrier 11 directly connected to the input shaft 15 rotates. In the casing 2, the supporting planetary gear 13 rolls on the sun gear 16 while rotating while meshing with the fixed internal gear 14.
Is rotated at the set gear ratio. The rotational force transmitted to the sun gear 16 is transmitted through the speed increasing gear 31 of the second step in the rear casing 2c connected by the support shaft 16a thereof to the speed increasing gear train 30 (gears 31, 32,
33, 34), the speed is increased to the required speed, and the rotational force is transmitted from the output shaft 35 to the power generator at high speed.

In the gear drive 1 thus configured, the bearing portion of the input shaft 15 in the casing 2 is
An inner ring 19a of a roller bearing 19 provided in the bearing housing 18 is extended outward, and the lip portion of the oil seal 21 is brought into contact with the peripheral surface of the extension 19a ′ of the inner ring 19a. Therefore, the surface that comes into contact with the oil seal 21 is a high-precision surface, and is a finished surface that far exceeds the surface accuracy of the input shaft 15 that is originally formed integrally with the carrier 11,
It is possible to maintain the sealing function for a long time without damaging the lip of the seal.

Therefore, as a speed increaser in a facility such as a wind power generator in which parts cannot be replaced for a long period of time, it has an excellent effect of protecting the inside of the casing and continuing stable operation.

On the other hand, the sun gear 16 in the planetary gear mechanism 10 is formed integrally with the support shaft 16a thereof, and meshes with the planetary gear 13 inside the carrier 11 to transmit power, as described above. The spline 16c is fitted and connected and supported by the spline 16c in the boss portion 31a of the second step gear 31 rotatably supported by the bearings 22 and 23 in the rear casing 2c by extending one end rearward. The other end (tip) of the support shaft 16a
Is concentrically float-supported by a holder 27 that is detachably attached inside the input shaft 15 (hollow shaft) of the carrier 11.

The structure in which the end portion of the sun gear support shaft 16a is float-supported by the holder 27 is shown in FIG.
As illustrated in (a), it projects at the center of the inside of the holder 27 (the inside of the casing) that is fitted and bolted to the stepped mounting seat 26 formed inside the input shaft 15 (see FIG. 1). The steel ball 28 fitted and supported in the center of the installed boss 27a is
The sun gear 16 is pressed against and supported by the center of the tip end of the support shaft.

The stepped mounting seat 26 provided inside the input shaft 15 in which the holder 27 is mounted has an inner diameter D larger than the outer diameter dimension d of the sun gear 16. By doing so, when manufacturing a large gearbox (gear drive) as in this embodiment, when assembling the planetary gear mechanism 10 inside the casing 2, a heavy carrier is first incorporated. It is a preferable work procedure to assemble the sun gear 16 from the above, and therefore, the sun gear 16 and its supporting shaft 16a can be inserted into the inside through the inner diameter portion of the input shaft 15.

In addition, since the work is carried out with the shaft center line oriented in the vertical direction at the time of assembly, the rear end of the sun gear support shaft 16a is the second assembly of the speed increasing gear train 30 previously assembled.
Spline 16 provided in the shaft hole of step gear 31
Since the procedure is such that it is fitted with c and assembled, the fine adjustment is required to the degree of meshing between the plurality of planetary gears 13 and the sun gear 16 after assembly even if the processing accuracy is improved.

As described above, the steel ball 28 supported by the holder 27 arranged on the axis of the input shaft 15 is brought into contact with the other end of the sun gear 16 so that it is automatically driven during rotational driving. Therefore, it is possible to finely adjust the float support portion so that the meshing drive of the sun gear 16 and the planetary gear 13 can be smoothly performed.

As shown in FIG. 3 (b), the support shaft 16a of the sun gear 16 has a float support portion at the tip end thereof, and a contact surface (reception seat 16d) is formed at the center of the end surface on the support shaft 16a side. Then, a ring-shaped flat sliding piece 29 is held on the end surface of the boss portion 27b projecting from the center of the inside of the holder 27A attached to the input shaft 15 side, and the sliding piece 29 is attached to the supporting shaft 16a side. It can also be supported by abutting on the seat 16d. In this case, it is preferable that the sliding piece 29 is formed in a ring shape and is made of a metal having lubricity.

In the above description of the embodiments, the speed increaser incorporated in the wind turbine generator is described, but the invention is not limited to this, and a device in which the power transmission element attached to the input shaft is difficult to easily attach and detach. It is more effective when adopted in the gear drive device used in. Further, it can be similarly adopted when it is used as a speed reducer as well as a speed reducer.

[Brief description of drawings]

FIG. 1 is a developed cross-sectional view taken along the line AA in FIG. 2 of a gear drive system of this embodiment.

FIG. 2 is a right side view of FIG.

FIG. 3 is a diagram showing a support structure of a center portion of a sun gear support shaft, that is, a support structure diagram using a ball (a) and a support structure diagram using a flat type sliding piece (b).

[Explanation of symbols]

1 Gear drive 2 casing 2a Front cover 2b Casing body 2c Rear casing 10 Planetary gear mechanism 11 Planetary gear carriers 13 planetary gears 14 Internal gear 15 Input axis 16 Sun Gear 16a Sun gear support shaft 16c spline 16d seat 18 Bearing housing 19 Roller bearing 19a Bearing inner ring 19a 'Inner ring extension 20 Bearing retainer 21 oil seal 26 Holder mounting seat 27,27A holder 28 steel balls 29 Sliding piece 30 speed increasing gear train 35 Output shaft

Continued front page    F term (reference) 3J016 AA02 BB03 CA02 CA03                 3J027 FA18 FB40 GA01 GB03 GC13                       GC22 GD03 GD09 GD12 GE01                       GE22                 3J063 AA40 AB02 AB12 AC01 BA01                       BA05 CA01 CB03 CB06 XA01

Claims (5)

[Claims] 1. In a gear drive device incorporating a planetary gear mechanism, an inner ring of a support bearing of a shaft body which is directly connected to a carrier of the planetary gear and projects to the outside of the casing is extended to the outside longer than the bearing width. A gear drive device characterized in that a seal ring mounted on a bearing housing is brought into contact with an outer peripheral surface of an inner ring extension portion. 2. A roller retainer is incorporated in the bearing portion, an inner ring of the bearing is extended outwardly by a required dimension, and a bearing retainer is attached to an outer peripheral surface of the extended portion of the inner ring on an outer surface portion of the housing of the bearing. The gear drive device according to claim 1, wherein the seal ring fitted to the member is brought into contact with the seal ring. 3. A gear drive device incorporating a planetary gear mechanism, wherein a sun gear arranged inside the carrier of the planetary gear so as to mesh with the planetary gear is inserted from the inside of a low speed side hollow shaft of the carrier. , One end of the sun gear support shaft is fitted and supported by the boss portion of the gear of the second step, and the other end of the sun gear support shaft is supported by the holder by a holder detachably attached to the low speed side hollow shaft. Gear drive device characterized by the following. 4. A float bearing is arranged at the center of the holder that supports one end of the sun gear support shaft.
The gear drive device according to. 5. The gear drive device according to claim 3, wherein the holder also serves as a lid that closes an internal space of the planetary gear carrier.