JPH08285017A - Hollow shaft type planetary reduction device, and centrifugal separator using it - Google Patents

Abstract

PURPOSE: To provide a hollow shaft type reduction device; capable of obtaining a sufficient bearing life and sufficient gear strength, and having excellent high- speed performance while sufficiently ensuring a hollow' shaft diameter; and a centrifugal separator using it. CONSTITUTION: This device is provided with a hollow shaft 2, a planetary frame 7 rotatably journaled to the shaft 2, a second input part 14 for transmitting rotation to the frame 7, a planetary gear 3 rotatably journaled to the frame 7 via a bearing 8, a rotation case 4 for covering the gear 3 to be engaged with the gear 3 via a first internal gear 18, a first input part for transmitting rotation to the case 4, a connecting member for connecting between the shaft 2 and the gear 3 via a second gear 22, a first output part 41 for outputting rotation from the case 4, and a second output part 40 for outputting rotation from the hollow shaft. The gears 18 and 22 are engaged with the gear 3 by differenciating the number of a tooth with each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow shaft type planetary speed reducer used in a centrifugal separator or the like.

[0002]

2. Description of the Related Art Generally, a simple planetary speed reducer or a cyclo speed reducer is used as a hollow shaft type speed reducer used in a centrifugal separator or the like for rotating sludge at high speed to separate sludge and water.

First, as the simple planetary speed reducer 100,
As shown in FIG. 5, the hollow shaft 102 connected to the screw conveyor 201 (rotary carrier) of the centrifuge 200.
And a rotating case connected to the first input pulley 104 and the case 202 (hollow rotating body) of the centrifuge 200 while forming a space Z between the hollow shaft 102 and the bearing 103. 105, a large-diameter sun gear 106 arranged in the space Z, and the sun gear 106 and the first internal gear 1 of the rotating case 105 based on the axis of the sun gear 106.
Two sets of planetary gear mechanisms 110 and 111 composed of a planetary gear 109 that rotates between 07 and a bearing 108, and a frame body 1 that connects the planetary gear mechanism 110 and the second input pulley 112.
13 and a connecting member 114 that connects the planetary gear mechanism 111 and the hollow shaft 102. In addition, the planetary gear mechanisms 110 and 111 have a total speed ratio I of the rotation speeds V1 and V2 of the case 202 connected to the rotating case 105 and the screw conveyor 201 connected to the hollow shaft 102, for example, I = 20. It is supposed to be. The rotating case 105 and the hollow shaft 10 are connected to the input pulleys 110 and 112.
2 and almost the same number of rotations V3, V4 (however, V3> V
When rotated in 4), two sets of planetary gear mechanisms 110, 111
The case 202 connected to the rotating case 105 has a rotation speed V1 = V3, and the screw conveyor 201 connected to the hollow shaft 102 has a rotation speed V2 = V3- (V3-V
4) / I, respectively, that is, the rotation speed difference between the first input unit 101 and the second input unit 112 at the time of input is reduced (decreased) to reduce the hollow of the hollow shaft type speed reducer 100. Axis 10
The water-soluble sludge and the like, which are sequentially fed into the centrifuge 200 from inside 2, are centrifugally separated into an aqueous solution and sludge, and the sludge is conveyed by the screw conveyor 201 and taken out of the centrifuge.

Further, as the cyclodeceleration device 250,
As shown in FIG. 6, a curved plate 251 having a cycloidal curve with the number of teeth equal to the reduction ratio engraved on the outer periphery, and a high speed shaft 252.
And an eccentric body 253 which is fixed to the center of the curved plate 251 via a bearing and is axially supported with an eccentricity θ.
An outer pin 25 provided on the outer circumference of 1 by one more than this number of teeth
4 and a low speed shaft 258 having a plurality of inner pins 257 fitted in through holes 256 formed in the curved plate 251 as main parts. Then, when the high speed shaft 252 rotates, the eccentric body 253 and the curved plate 251 move to the outer pin 25.
4 causes an eccentric movement around the center of the curved plate 25
The tooth profile of 1 is pressed against the outer pin 254, resulting in 1
During one eccentric movement, the curved plate 251 is moved one tooth at a time in the direction opposite to the eccentric movement direction to decelerate, and the decelerated movement is transmitted to the low speed shaft 258 via the inner pin 257.

[0005]

However, in the conventional simple planetary speed reducer, each planetary gear mechanism 110, 1 is used.
Since 11 is composed of the sun gear 106 and the planetary gear 109, when the rotating case 105 and the hollow shaft 102 are rotated, the sun gear 106 and the planetary gear 1 are rotated as shown in FIG.
The centrifugal forces F1 and F2 toward the rotating case 105 are included in 09.
However, the centrifugal force F3 directed to the sun gear 106 acts on the rotating case 105 (however, the centrifugal forces F1 and F3 cancel each other out), and the sun gear 106 and the planet gears 109 as well as the planet gears 109. And the first internal gear 107 (rotating case 105) are tangential force f in the same tangent direction.
1, f2, f3 are generated, and the combined force f of these is generated by the bearing 10
In order to suppress the centrifugal force and the like as much as possible, the hollow shaft 10 acts on the bearing 10 of the planetary gear 109 and the balance between the hollow shaft 102 and the rotating case 105.
It is necessary to keep the space between the rotary case 105 and the rotary case 105 small and to reduce the size of the entire reduction gear device.
In order to send in large quantities of objects that are centrifuged by 0,
When the diameter of the hollow shaft 102 is increased, the sun gear 106, the planetary gear 109, the bearing 108, etc. are reduced in proportion to this. Therefore, when the centrifugal force F3 or the synthetic force f acts, the life of the bearing 108 and each gear There was a problem that the strength of 106 and 109 was shortened and a sufficient rotation speed could not be secured.

Further, in the cyclodeceleration device 250, usually two curved plates are used 180 ° out of phase with each other in order to avoid the vibration due to the eccentricity of the curved plate 251, but even in this case, the high speed shaft is also used. There is a problem in that vibration due to the couple of 252 cannot be avoided, and it is difficult to apply it to a centrifugal separator and rotate at high speed.

The present invention has been made to solve such a problem, and while ensuring a sufficient diameter of the hollow shaft,
It is an object of the present invention to provide a hollow shaft type speed reducer capable of obtaining a sufficient bearing life and gear strength and excellent in high speed performance, and a centrifuge using the same.

[0008]

In order to solve the above problems, in a hollow shaft type speed reducer and a centrifuge having the same according to the present invention, in claim 1, the hollow shaft and the outer periphery of the hollow shaft are rotated. A planet frame that is rotatably supported, a second input portion that transmits rotation to the planet frame, a planet gear that is rotatably supported by a bearing on the planet frame, and a planet gear that covers the planet gear. A rotating case that meshes with a planetary gear via a first internal gear, a first input portion that transmits rotation to the rotating case, and a connecting member that connects the hollow shaft and the planetary gear via a second internal gear. A first output portion that outputs rotation from the rotating case and a second output portion that outputs rotation from the hollow shaft
An output unit is provided, and the first internal gear and the second internal gear are meshed with the planetary gear with different numbers of teeth.

According to another aspect of the present invention, there is provided a hollow rotary body and a rotary carrier rotatably provided in the hollow rotary body, wherein the hollow rotary body and the rotary carrier are hollow shaft type planetary speed reducers. In the centrifuge, the hollow shaft type planetary speed reducer is rotated at a reduced speed by a hollow shaft, a planetary frame rotatably supported outside the hollow shaft, and the planetary frame. A second input portion for transmitting rotation to the planetary gear, a planetary gear rotatably supported by the planetary frame via bearings, and a rotation that covers the planetary gear and meshes with the planetary gear via the first internal gear. A case and a first case for transmitting rotation to the rotating case
An input unit, a connecting member that connects the hollow shaft and the planetary gear via a second internal gear, a first output unit that outputs rotation from the rotating case, and a first output unit that outputs rotation from the hollow shaft Two output parts are provided, and the first internal gear and the second internal gear are meshed with the planetary gears with a difference in the number of teeth, and the first output part has the hollow rotating body. In addition, the second output units are respectively connected to the rotary carrier.

[0010]

As described above, according to the hollow speed reducer of the present invention and the centrifugal separator using the same, the planetary gear mechanism is configured only with the planetary gears and is arranged in the space, and the planetary gears and the hollow shaft are connected. Since the first internal gear and the second internal gear are connected to each other by the second internal gear formed on the member and mesh with the planetary gears by providing a difference in the number of teeth between them, it is hollow as long as the sun gear is not arranged. The diameter of the shaft and the planetary gear can be increased,
Since the centrifugal force and the tangential force of the first internal gear and the second internal gear act in mutually opposite directions to exert the deceleration effect and the force acting on the bearing can be used as the couple of the tangential force. It is possible to improve high-speed performance while obtaining sufficient bearing life and planetary gear strength.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A hollow shaft type speed reducer and a centrifuge using the same according to an embodiment of the present invention will be described below with reference to the drawings. 1 is a partial cross-sectional view showing the structure of a hollow shaft type speed reducer in the present embodiment, FIG. 2 is a schematic symbol view showing the structure of the hollow shaft type speed reducer in the present embodiment, and FIG. 3 is a hollow shaft type in the present embodiment. FIG. 4 is a cross-sectional view showing the configuration of a centrifuge in which the speed reducer is used, and FIG. 4 is a cross-sectional view taken along the line AA of FIG. 1 showing a force relationship that acts during rotation of the hollow shaft speed reducer in this embodiment.

In FIGS. 1 and 2, reference numeral 1 is a hollow shaft speed reducer, which is mainly composed of a hollow shaft 2, a planetary gear 3, and a rotating case 4. The hollow shaft 2 has a shaft portion 2
A, a flange portion 2B protruding outward in the radial direction on one end side of the shaft portion 2A, and a large-diameter shaft portion 2C extending in the axial direction from the flange portion 2B are integrally formed, and the outer periphery of the flange portion 2B A gear 6 is formed on the surface. Also,
On the shaft portion 2A of the hollow shaft 2, a planetary frame 7 is rotatably supported at both ends via bearings 8 and 9 from the opposite side from which the flange portion 2B projects. This planetary frame 7 includes the first frame portion 7
It is divided into two parts, A and the second frame part 7B, and the planetary gear 3 is arranged between the first frame part 7A and the seventh frame part.
The planetary gear 3 has a shaft portion 12 rotatably through bearings 11 and 11 in recesses 10 and 10 formed in the frame portions 7A and 7B at both ends, and a planetary gear formed integrally with the shaft portion 12. The outer peripheral surface of the frame 7 and the gear portion 13 projecting radially outward. Further, the first frame portion 7A of the planetary frame 7 is
The second input pulley 14 is connected to the input pulley 14 and is rotated by the drive source 60 (drive motor).
The planetary gear 3 is rotated in the same direction via the planetary frame 7.

The rotating case 4 is a shaft-like body having a space A for housing the planetary gear 3 while covering the planetary gear 3 from the outside.
And the large-diameter shaft portion 2C of the hollow shaft 2 are rotatably supported by the planetary frame 7 and the hollow shaft 2 by bearings 15 and 16 which are externally fitted. The end portion of the rotating case 4 on the side of the first frame portion 7A is connected to the first input pulley 17 which is rotated by a drive source 60 (driving motor) and is rotated, and at the same time the inner peripheral surface 7a is covered. Is provided with a first internal gear 18 that meshes with the planetary gear 3. Further, in the gap H between the rotating case 4 and the planetary gear 3, a joint gear 20 serving as a connecting member is arranged. The joint gear 20 has a concave cross-sectional shape that protrudes from the vicinity of the first internal gear 18 of the rotating case 4 toward the large diameter shaft portion 2C of the hollow shaft 2 and is bent to extend to the gear portion 6 of the flange portion 2B. A gear 21 that meshes with the gear 6 of the flange portion 2B and a second internal gear 22 that meshes with the planetary gear 3 and is formed over the circumference are formed. Further, the first internal gear 18 and the second internal gear 22 are provided with a difference in the number of teeth Z1 and Z2. In addition, 30, 31
Is an oil seal material interposed between the planet frame 7 and the hollow shaft 2, and 32 and 33 are the rotating case 4 and the planet frame 7 or the hollow shaft 2.
Oil seal material interposed between the large diameter portion 2C of the
Is a plate member interposed between the first internal gear 18 and the rotating case 4. A plurality of planetary gears 3 are provided at predetermined intervals in the circumferential direction of the first internal gear 18.

The hollow shaft type speed reducer 1 is connected to the centrifuge 50 shown in FIG. The centrifuge 50 shown in FIGS. 1 and 2 has a cylindrical ball body 51 as a hollow rotating body.
And a screw conveyor 52 installed in the cylindrical ball body 51 as main parts. The screw conveyer 52 has a rotating shaft 53 and a plurality of disturbing plate portions 54 extending outward in the radial direction of the rotating shaft 53, and the aqueous solution is disturbed by the disturbing plate portion 54 to dissolve the water-soluble sludge. And centrifuge into sludge. In the centrifuge 50, the hollow shaft 2 of the hollow shaft type speed reducer 1 is connected to the screw conveyor 52 as the second output unit 40, and the rotating case 4 is connected to the tubular ball body 12 as the first output unit 41. Has been done.

The hollow shaft type speed reducer 1 of the present embodiment and the centrifuge 50 using the same are configured as described above.
Next, the hollow shaft type speed reducer 1 and the centrifuge 5 of the present embodiment.
The operation of 0 will be described.

First, by driving a drive source (not shown), the first
The input pulley 17 and the second input pulley 14 are rotated in the same direction at almost the same rotation speeds Va and Vb (where Va> V
Then, the rotating case 4 is rotated via the bearings 15 and 16 and the planetary gear 3 is rotated via the planetary frame 7. When the rotating case 4 and the planet frame 7 rotate,
Since there is a difference in the number of teeth Z1 and Z2 between the first internal gear 18 and the second internal gear 22, the speed ratio I between the rotational speed Vc of the first output unit 41 and the rotational speed Vd of the second output unit 40 is I = Z2 / (Z1
-Z2), the rotation speed V of the first output unit 41
c is Va, and the rotation speed Vd of the second output unit 40 is Vd = Va−
(Va-Vb) / I, which is transmitted to the cylindrical ball body 51 of the centrifuge 50 and the screw conveyor 52 to rotate at the rotation speeds Vc and Vd, respectively. Accordingly, the difference between the rotation speeds Va and Vb of the planetary frame 7 or the rotating case rotated by the input pulleys 14 and 17 is reduced by the difference in the number of teeth between the first internal gear 18 and the second gear 22 (small. Then, the centrifuge 50 rotated by the first output unit 41 or the second output unit 40.
The cylindrical ball body 51 and the screw conveyor 52 can be rotated Vc and Vd.

At this time, when the planetary gear 3 and the rotating case 4 of the hollow shaft type planetary speed reducer 1 rotate, as shown in FIG. 4, the planetary gear 3 has a centrifugal force Fa toward the rotating case 4,
The centrifugal force Fb toward the planetary gears 3 acts on the rotating case 4 in directions opposite to each other, and the first internal gear 18 and the second internal gear 22 meshing with the planetary gears 3 are in opposite directions at their meshing portions. The centrifugal forces Fa and Fb cancel each other out, and since the tangential forces fa and fb are opposite in direction to each other, the bearings 11, 11 of the planetary gear 3, etc. A couple acts only on.

Next, the cylindrical ball body 5 of the centrifuge 50.
When the 1 and the screw conveyor 52 rotate, the hollow shaft 2
Water-soluble sludge sequentially fed into the centrifugal separator 50 through the inside of the tubular ball body 51 through a communication hole 55 formed between the hollow shaft 2 and the rotary shaft 53 of the screw conveyor 52. Flow into. And the screw conveyor 5
By the rotation of 2, the aqueous solution having a small mass due to the centrifugal force while being stirred by the plurality of disturbing plate portions 54 is conveyed along the upper surface of the cylindrical ball 51 to the liquid discharge port (not shown) by the rotation. The sludge, from which the aqueous solution having a large mass is separated, precipitates in the lower part of the cylindrical ball 51 while increasing its concentration (decreasing the content of the aqueous solution) by the centrifugal force generated by the rotation of the screw conveyor 52, and the screw conveyor. 5
It is conveyed to a concentration discharge port (not shown) by the disturbing plate portion 54 of No. 2 and is centrifuged into an aqueous solution and a concentrated sludge.

[0019]

As described above, according to the hollow planetary speed reducer of the present invention, the planetary gear mechanism is composed only of the planetary gears and arranged in the space, and the planetary gears and the hollow shaft are formed in the connecting member. Since the first gear and the second gear are connected to each other by the second internal gear and are meshed with the planetary gear with a difference in the number of teeth between them, the diameter of the hollow shaft and the planetary gear are not increased because the sun gear is not arranged. The gear can be made larger, and the first internal gear and the second gear
The centrifugal force and tangential force with the internal gear act in mutually opposite directions to exert the deceleration effect and the force acting on the bearing can be used as the couple of the tangential force. Even if it is increased, it is possible to improve high-speed performance while obtaining a sufficient bearing life and planetary gear strength. As a result, even when the hollow shaft type planetary speed reducer of the present invention is used in a centrifugal separator, while reducing the rotational speed difference between the hollow rotor and the rotary carrier while obtaining the life of the bearing and the strength of the gear, It becomes possible to quickly separate the separated object that is conveyed from inside the hollow shaft by rotating at high speed.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing the structure of a hollow shaft type planetary speed reducer according to an embodiment of the present invention.

FIG. 2 is a schematic symbol diagram showing a configuration of a hollow shaft type planetary speed reducer in one embodiment of the present invention.

FIG. 3 is a cross-sectional view illustrating the configuration of a centrifuge in which a hollow shaft type planetary speed reducer according to an embodiment of the present invention is used.

FIG. 4 is a cross-sectional view taken along the line AA of FIG. 1 showing a force relationship that acts during rotation of the hollow shaft reduction gear device according to the embodiment of the present invention.

FIG. 5 is a schematic symbol diagram showing a configuration of a simple planetary speed reducer in a conventional technique.

FIG. 6 is a perspective view showing a configuration of a cyclo speed reducer in the related art.

FIG. 7 is a cross-sectional view showing a relationship of forces acting during rotation of a simple planetary speed reducer in the related art.

[Explanation of symbols]

 2 Hollow shaft 3 Planetary gear 4 Rotating case 13 Planetary gear 14 Second input pulley (second input part) 17 First input pulley (first input part) 18 First internal gear 20 Joint gear (connecting member) 22 Second internal Gear 40 Second output section 41 First output section 51 Cylindrical ball body (hollow rotating body) 52 Screw conveyor (rotary carrier)

Claims (2)

[Claims] 1. A hollow shaft, a planetary frame rotatably supported on the outside of the hollow shaft, a second input section for transmitting rotation to the planetary frame, and a planetary frame rotatable via bearings. A planetary gear that is axially supported by the rotary gear, a rotary case that covers the planetary gear and meshes with the planetary gear via a first internal gear, a first input portion that transmits rotation to the rotary case, and the hollow shaft. A connecting member that connects the planetary gears through a second internal gear;
A first output unit that outputs rotation from the rotating case and a second output unit that outputs rotation from the hollow shaft are provided, and the first internal gear and the second internal gear have mutually the number of teeth. A hollow-diameter planetary speed reducer characterized in that the planetary gears are meshed with each other with a difference. 2. A hollow rotary body and a rotary transfer body rotatably provided in the hollow rotary body, wherein the hollow rotary body and the rotary transfer body are decelerated by a hollow shaft type planetary speed reducer. A centrifugal separator rotated at a rotation speed, wherein the hollow shaft type planetary speed reducer transmits a rotation to a hollow shaft, a planetary frame rotatably supported outside the hollow shaft, and the planetary frame. A second input portion, a planetary gear rotatably supported by the planetary frame via a bearing, a rotary case that covers the planetary gear and meshes with the planetary gear via a first internal gear, A first input section for transmitting rotation to the rotating case;
A connecting member that connects the hollow shaft and the planetary gear via a second internal gear, a first output unit that outputs rotation from the rotating case, and a second output unit that outputs rotation from the hollow shaft. The first internal gear and the second internal gear are meshed with the planetary gear with a difference in the number of teeth, and the first output portion is provided in the hollow rotating body, A centrifuge characterized in that two output parts are connected to the rotary carrier, respectively.