JP6426017B2 - Rotating device - Google Patents

Description

  The present invention relates to a rotating device.

  In a rotating device such as a reduction gear, components such as gears rotate at high speed therein. Therefore, in order to prevent the occurrence of damage such as burn-in, a lubricant is enclosed in the rotating device. Conventionally, a rotating device as described in, for example, Patent Document 1 has been proposed.

JP, 2012-57792, A

  The rotating device is generally provided with a pump mechanism for supplying to the upper part the lubricant accumulated at the lower part by gravity when it is used vertically. The pump mechanism is driven by a cam member attached to the rotational shaft of the rotating device. Since the cam member is usually fixed to the rotating shaft by the key, the cam member requires a key groove. Therefore, the diameter of the cam member is increased by the amount of the key groove.

  The present invention has been made in view of these circumstances, and an object thereof is to provide a rotating device capable of suppressing an increase in diameter of a cam member.

  In order to solve the above problems, a rotating device according to an aspect of the present invention comprises a rotating shaft, a pair of bearings supporting the rotating shaft, a pump mechanism for circulating a lubricant, and a pump mechanism attached to the rotating shaft. And a cam member, and the cam member is disposed between the pair of bearings and has a pressing mechanism that presses the inner ring of the bearing against the cam member. The cam member is circumferentially fixed with respect to the rotation shaft by being pinched by the inner rings of the pair of bearings.

  According to this aspect, the cam member is circumferentially fixed to the rotation shaft by being pinched by the inner rings of the pair of bearings. That is, the cam member is fixed to the rotation shaft without using a key.

  It is to be noted that any combination of the above-described constituent elements, or one obtained by replacing the constituent elements and expressions of the present invention among methods, apparatuses, systems, etc. is also effective as an aspect of the present invention.

  According to the present invention, it is possible to provide a rotating device capable of suppressing an increase in diameter of the cam member.

It is a sectional view of rotation device concerning an embodiment. It is an expanded sectional view expanding and showing near the bearing part of the output shaft of a reduction gear. It is an expanded sectional view expanding and showing a part of rotation device concerning a modification of an embodiment. It is an expanded sectional view expanding and showing a part of rotation device concerning a modification of an embodiment. It is an expanded sectional view expanding and showing a part of rotation device concerning a modification of an embodiment.

  Hereinafter, the same or equivalent constituent elements and members shown in the respective drawings are denoted by the same reference numerals, and redundant description will be appropriately omitted. In addition, dimensions of members in each drawing are shown appropriately enlarged or reduced for easy understanding. In each drawing, a part of members which are not important in describing the embodiment is omitted and displayed.

  FIG. 1 is a cross-sectional view showing a rotation device 10 according to the first embodiment. The rotating device 10 includes a motor 12, a blower 14 for cooling the motor 12, and a reduction gear 16 for reducing the rotational force of the motor 12. The rotation device 10 of the embodiment is a rotation device used vertically, that is, a rotation device in which the reduction gear 16 is disposed vertically lower than the motor 12.

  The motor 12 is, for example, a squirrel cage induction motor, and includes a motor casing 20, a stator 22, a rotor 24, a motor shaft 26, and bearings 28, 30. The motor casing 20 includes a housing 32, a first bracket 34 and a second bracket 36. The housing 32 is formed in a cylindrical shape. The first bracket 34 is coupled to an end of the housing 32 on the blower 14 side, and rotatably supports the motor shaft 26 via a bearing 28. The second bracket 36 is coupled to an end of the housing 32 on the reduction gear 16 side, and rotatably supports the motor shaft 26 via the bearing 30. The first and second brackets 34 and 36 and the housing 32 are fastened by bolts 38 and 40, respectively.

  In the motor casing 20, a stator 22 and a rotor 24 are accommodated. The motor casing 20 is made of, for example, aluminum die-cast, cast iron or steel plate and supports the weight of the stator 22 and the rotor 24 and radiates the heat generated from the stator etc. to the outside of the motor. A plurality of heat dissipating fins 42 extending in a direction parallel to the motor shaft 26 are formed on the outer periphery of the housing 32 in order to enhance the heat dissipating performance.

  The stator 22 is formed by laminating a large number of thin plate-like (e.g., 0.5 mm thick) electromagnetic steel plates stamped in the same shape. The stator 22 is fitted to the inner periphery 32 a of the housing 32 by, for example, shrink fitting. In a plurality of slots (not shown) formed in the stator 22, coils 44 of copper wire are wound a predetermined number of times.

  Similarly to the stator 22, the rotor 24 is formed by laminating a large number of thin electromagnetic steel plates which are stamped in the same circular shape. A circular hole 24 a for inserting the motor shaft 26 is formed at the center of the rotor 24. A plurality of radially extending slots (not shown) are formed on the outer peripheral side of the rotor 24 at equal intervals, and a conductor such as aluminum or copper is cast in the slots by die casting.

  The motor shaft 26 projects from both sides of the first bracket 34 and the second bracket 36. The first protrusion 26 a protruding from the first bracket 34 extends to the inside of the blower 14 and also functions as a rotation shaft of the fan 50 (described later). The second protrusion 26 b protruding from the second bracket 36 extends to the inside of the reduction gear 16 and also functions as an input shaft of the reduction gear 16. The motor shaft 26 and the input shaft of the reduction gear 16 may be separately configured, and both may be coupled by coupling, spline fitting, or the like.

  The blower 14 includes a fan 50 and a fan cover 52. The fan 50 is fixed to the first protrusion 26 a of the motor shaft 26 and rotates integrally with the motor shaft 26. The fan cover 52 is formed in a substantially cup-shaped predetermined shape and covers the fan 50. The fan cover 52 also has a role of guiding the wind generated by the fan 50 to the radiation fins 42 formed on the outer periphery of the housing 32.

  The reduction gear 16 is a kind of a planetary gear reduction gear called an eccentric rocking mesh type. The reduction gear 16 includes an input shaft 26b, external gears 60 and 62, eccentric bodies 64 and 66, roller bearings 68 and 70, an internal gear 72, a reduction gear casing 74, an output shaft 76, and a carrier. Body 78, inner pin 80, bearings 82, 84, pump mechanism 88, cam member 46, and bearing nut 98.

  The input shaft 26 b is integrally formed with the motor shaft 26 and disposed at the radial center of the external gears 60, 62. On the outer periphery of the input shaft 26b, eccentric bodies 64 and 66 offset from the input shaft 26b are fixed or fitted. The eccentric bodies 64 and 66 are decentered with a phase difference of 180 degrees. Although the eccentric bodies 64 and 66 are integrally formed in FIG. 1, they may be separately formed and separately fixed or fitted to the input shaft 26b. Alternatively, the eccentrics 64, 66 and the input shaft 26b may be integrally formed.

  Two external gears 60 and 62 are rotatably fitted around the outer circumferences of the eccentric bodies 64 and 66 via roller bearings 68 and 70, respectively. The external gears 60 and 62 internally mesh with the internal gear 72, respectively.

  The internal gear 72 rotatably supports a cylindrical internal tooth pin 72a constituting an internal tooth, a holding pin 72b penetrating the internal tooth pin 72a and rotatably holding the same, and a holding pin 72b rotatably. And an internal gear main body 72c integrated with the reduction gear casing 74.

  A carrier body 78 integrally formed with the output shaft 76 of the reduction gear 16 is disposed on the opposite side of the external gear 60, 62 to the motor 12. A plurality of axially extending inner pins 80 are fitted in through holes 78 a formed along the outer periphery of the carrier body 78.

  In the external gear 60, a plurality of through holes of the same diameter are formed at equal intervals at positions offset from the axial center. The inner pins 80 extending from the carrier body 78 are respectively inserted into these through holes. Corrugated teeth are formed on the outer periphery of the external gear 60, and the teeth move while being in contact with the internal tooth pin 72a of the internal gear 72, so that the external is made in a plane normal to the central axis. The tooth gear 60 can swing. The external gear 62 is the same except that there is a phase difference of 180 degrees with respect to the external gear 60.

  The reduction gear casing 74 rotatably supports the output shaft 76 via a pair of bearings 82 and 84. The output shaft 76 is disposed coaxially with the motor shaft 26. A lubricant is enclosed inside the reduction gear casing 74. This lubricant also acts as a coolant. The lubricant collects under the reduction gear casing 74 by gravity.

  FIG. 2 is an enlarged sectional view showing the vicinity of the bearing portion of the output shaft 76 of the reduction gear 16 in an enlarged manner. The bearing 82 includes an inner ring 82a fitted on the output shaft 76, a rolling element 82b, a retainer 82c holding the rolling element 82b, and an outer ring 82d. The bearing 84 includes an inner ring 84a fitted on the output shaft 76, a rolling element 84b, a retainer 84c holding the rolling element 84b, and an outer ring 84d.

  The cam member 46 includes a cam body 48, a spacer 54, and a spacing adjustment body 56. The cam body 48 is a plate cam having a substantially petal shape as viewed in the axial direction, and the output shaft 76 is inserted into a circular hole 48 a formed at the center thereof. The cam body 48 may have a substantially egg shape or another shape in an axial direction. The spacer 54 is an annular member surrounding the output shaft 76, and is provided between the bearing 82 and the cam body 48. When viewed in the radial direction, the spacer 54 overlaps the retainer 82c. The spacer 54 may be separate from or integral with the cam body 48.

The space adjustment body 56 is an annular member surrounding the output shaft 76, and is provided between the bearing 84 and the cam body 48. When viewed from the radial direction, the space adjusting member 56 overlaps the retainer 84 c. In the present embodiment, the axial length L4 of the space adjusting member 56 is adjusted such that the “inner gap of the bearing” expressed by the following equation has a desired value.
Bearing internal clearance = (L1 + L2 + L3 + L4 + L5)-(L6 + L7 + L8)
L1: axial length of the inner ring 82a of the bearing 82 L2: axial length of the spacer 54 L3: axial length of the cam body 48 L4: axial length of the space adjusting member 56 L5: the inner ring 84a of the bearing 84 Axial length L6: An axial distance between the non-load side end face of the inner ring 82a and the load side end face of the outer ring 82d when the bearing 82 is incorporated L7: anti-protrusion 74a of the reduction gear casing 74 for positioning the outer ring 82d Axial distance between the load side end face 74b and the load side end face 74d of the projection 74c of the reduction gear casing 74 for positioning the outer ring 84d L8: The load side end face 74d of the projection 74c and the load side end face of the inner ring 84a Axial distance

  The bearing nut (pressing mechanism) 98 presses the bearing 84 toward the bearing 82 by being screwed into an external thread formed on the outer peripheral surface of the output shaft 76. The bearing nut 98 in particular presses the inner ring 84 a of the bearing 84 against the cam member 46.

  The pump mechanism 88 includes a pump portion 90 and a lubricating passage 92. The lubricating passage 92 has one end leading to the pump portion 90 and the other end leading to the inside of the reduction gear casing 74 on the motor 12 side of the external gear 60. That is, the lubricating passage 92 communicates the vertically lower side and the vertically upper side of the reduction gear casing 74 via the pump portion 90.

  The pump portion 90 includes a cylinder 94 and a piston 96. The piston 96 is driven along the cam surface 48 b (outer peripheral surface) of the cam body 48 to reciprocate in the cylinder 94. The lubricant is drawn from the reduction gear casing 74 into the cylinder 94 by the reciprocating motion, and is discharged from the cylinder 94 to the lubricating passage 92. As a result, the lubricant accumulated under the reduction gear casing 74 by gravity is supplied to the upper portion of the reduction gear casing 74 through the lubricating passage 92, and the lubricant circulates in the reduction gear casing 74.

A procedure for assembling the bearing portion of the output shaft 76 of the reduction gear 16 in the rotating device 10 configured as described above will be described.
1. The outer ring 82 d of the bearing 82 is fitted to the reduction gear casing 74.
2. The inner ring 82 a of the bearing 82, the rolling element 82 b and the cam member 46 are fitted on the output shaft 76.
3. The output shaft 76 in which the inner ring 82a and the like of the bearing 82 are fitted is inserted into the reduction gear casing 74 in which the outer ring 82d of the bearing 82 is fitted.
4. The bearing 84 is fitted on the output shaft 76.
5. The bearing nut 98 is tightened to press the inner ring 84 a of the bearing 84 against the inner ring 82 a of the bearing 82, and the cam member 46 is sandwiched between the inner ring 84 a of the bearing 84 and the inner ring 84 a of the bearing 82.
The spacing adjustment body 56 of the cam member 46 may be fitted to the output shaft 76 between procedure 3 and procedure 4.

  The operation of the rotating device 10 configured as described above will be described. When the motor 12 is driven, the rotor 24 and the motor shaft 26 rotate relative to the stator 22, and the input shaft 26b of the reduction gear 16 integrated with the motor shaft 26 rotates. When the input shaft 26 b rotates, the outer circumferences of the eccentrics 64 and 66 perform eccentric movement, and the external gears 60 and 62 swing through the roller bearings 68 and 70. Due to this rocking, a phenomenon occurs in which the meshing positions of the external teeth of the external gear 60, 62 and the internal tooth pin 72a of the internal gear 72 are sequentially shifted.

  The difference in number of teeth between the external gears 60 and 62 and the internal gear 72 is set to "1" in the present embodiment. Further, since the internal gear 72 is integral with the reduction gear casing 74, the rotation of the internal gear 72 is restrained. Therefore, each time the input shaft 26b makes one rotation, the external gears 60, 62 rotate (rotate) by an amount corresponding to the difference in the number of teeth with respect to the internal gear 72 whose rotation is restricted. The rotation is transmitted to the carrier body 78 through the inner pin 80 inserted in the through hole of the external gears 60, 62. As a result, due to the rotation of the input shaft 26b, the carrier 78 and the output shaft 76 integral with the carrier 78 are rotated at a rotational speed reduced to 1 / (the number of teeth of the external gear).

  In addition, when the output shaft 76 rotates, the piston 96 follows the cam surface 48 b of the cam body 48 and reciprocates in the cylinder 94. The lubricant is drawn from the reduction gear casing 74 into the cylinder 94 by the reciprocating motion, and is discharged from the cylinder 94 to the lubricating passage 92. As a result, the lubricant accumulated under the reduction gear casing 74 by gravity is supplied to the upper portion of the reduction gear casing 74 through the lubricating passage 92.

  According to the rotation device 10 according to the embodiment described above, the cam member 46 is sandwiched between the bearing 82 and the bearing 84 so that the bearing 82 and the bearing 84 are circumferentially extended with respect to the output shaft 76. It is fixed not to rotate. That is, since the cam member 46 can be fixed to the output shaft 76 without using a key as in the prior art, no key groove is required in the cam member 46. When the key groove is not provided in the cam member 46, the diameter can be reduced as compared with the case where the key groove is provided. Further, since the cam member 46 can be used as a member for adjusting the distance between the bearing 82 and the bearing 84, it is not necessary to separately provide such a member. Therefore, the number of parts is reduced and the cost is reduced.

  Further, according to the rotation device 10 according to the embodiment, manufacturing errors of the cam body 48, the bearings 82, and the bearings 84 are absorbed by changing the axial length of the gap adjusting member 56, and the bearings 82 and 84 Interval can be adjusted to a desired interval. That is, since the distance can be adjusted by changing the axial length of the distance adjusting body 56 which has a simple shape as compared with the cam main body 48, the adjustment becomes easy. Further, in this case, a plurality of types of spacing adjustment bodies 56 having different axial lengths are prepared in advance, and among them, the spacing of the axial length according to the manufacturing error of the cam main body 48, the bearing 82 and the bearing 84 The adjuster 56 may be selected. With regard to the space adjusting body 56 having a simple shape, a plurality of kinds of space adjusting bodies 56 having different axial lengths are prepared, while the cam body having a complicated shape can be suppressed to one type or several types. The manufacturing cost can be reduced.

  The configuration and operation of the rotation device according to the embodiment have been described above. It is understood by those skilled in the art that this embodiment is an exemplification, and that various modifications can be made to the combination of the respective constituent elements, and such modifications are also within the scope of the present invention.

(Modification 1)
Although the embodiment has described the case where the reduction gear 16 includes one pump mechanism, it is not limited thereto. The reduction gear 16 may include two or more pump mechanisms.
FIG. 3 is an enlarged cross-sectional view showing the vicinity of the bearing portion of the output shaft 76 of the reduction gear 16 of the rotation device according to the modification of the embodiment. FIG. 3 corresponds to FIG. In the present variation, the reduction gear 16 includes a pump mechanism 89 in addition to the pump mechanism 88. The pump mechanism 89 is configured similarly to the pump mechanism 88. The two pump mechanisms 88 and 89 are provided at intervals of 180 in the circumferential direction. In this case, the lubricant can be lubricated more by the amount of the pump mechanism.

  Further, in the present modification, the cam member 46 includes a cam main body 148 and a distance adjustment body 56. The cam main body 148 is a member in which the cam main body 48 of the embodiment and the spacer 54 are integrated. The circular hole 148a and the cam surface 148b (the outer peripheral surface) of the cam body 148 correspond to the circular hole 48a and the cam surface 48b of the cam body 48, respectively.

  Furthermore, in the present modification, the reduction gear 16 includes high friction members 104 and 106. The high friction member 104 is provided between the inner ring 82 a of the bearing 82 and the cam body 148. The high friction member 106 is provided between the inner ring 84 a of the bearing 84 and the distance adjusting member 56. For example, urethane resin or rubber is used as the high friction members 104 and 106. More specifically, in the high friction member 104, the coefficient of friction between the high friction member 104 and the inner ring 82a and the coefficient of friction between the high friction member 104 and the cam body 148 The member which becomes large also is adopted. Similarly, in the high friction member 106, the coefficient of friction between the high friction member 106 and the inner ring 84a and the coefficient of friction between the high friction member 106 and the distance adjusting member 56 are higher than the coefficient of friction between the inner ring 84a and the distance adjusting member 56. A member which becomes large is adopted. The high friction member may be provided on either of the inner ring 82 a and the cam body 148 or the inner ring 84 a and the distance adjusting member 56. In addition, a high friction member may be provided between the cam body 148 and the distance adjustment body 56. According to this modification, the cam member 46 can be more firmly fixed to the motor shaft 26 in the circumferential direction.

(Modification 2)
In the embodiment, the case where the bearing 84 is pressed against the cam member 46 by tightening with the bearing nut 98 has been described, but the pressing mechanism of the present invention is not limited to this. For example, the bearing 84 may be pressed against the cam member 46 by a snap ring or other means.
FIG. 4 is an enlarged cross-sectional view showing the vicinity of the bearing portion of the output shaft 76 of the reduction gear 16 of the rotation device according to the modification of the embodiment. In the present variation, the reduction gear 16 includes a retaining ring 100 and a shim 102 instead of the bearing nut. The retaining ring 100 is a C ring and fits in an annular groove 76 a formed in the output shaft 76. The shim 102 is inserted between the retaining ring 100 and the inner ring 84 a of the bearing 84. The axial movement of the bearing 84 and the cam member 46 is restricted by the snap ring 100 via the shim 102. Further, by adjusting the axial thickness of the shim 102, the force with which the bearing 84 presses the cam member 46 is adjusted. According to the rotation device of the present modification, the same effects as those of the rotation device 10 according to the embodiment can be obtained.

(Modification 3)
FIG. 5 is an enlarged sectional view showing the vicinity of the bearing portion of the output shaft 76 of the reduction gear 16 of the rotation device according to the modification of the embodiment. The cam member 46 includes the cam main body 148 and the spacing adjustment body 56 as in the first modification. In this modification, the output shaft 76 is formed such that the outer diameter D1 of the portion where the bearing 82 is disposed is larger than the outer diameter D2 of the portion where the bearing 84 is disposed. Therefore, each member of the bearing 82 is formed larger in diameter than each member of the bearing 84. Thus, the gap between the output shaft 76 and the retainer 82c is increased, and the radial thickness t1 of the cam main body 148 entering the gap can be increased. In particular, the radial thickness t1 of the cam body 148 can be made thicker than the radial thickness t2 of the space adjusting member 56.

(Modification 4)
In the embodiment, as the reduction gear mechanism of the reduction gear 16, the case of adopting the rocking inscribed meshing type reduction gear mechanism of the type in which the input shaft (eccentric body shaft) 26b is disposed at the center of the internal gear 72 has been described. However, the reduction mechanism of the reduction gear 16 used with the motor 12 according to the present invention is not limited to this. For example, a simple planetary gear reduction mechanism or a planetary gear reduction mechanism of a type in which a plurality of eccentric body shafts are disposed at a position offset from the center of the internal gear may be adopted. Further, instead of the single-stage reduction mechanism in which the input shaft 26 b and the output shaft 76 are coaxial, a multi-axial or multi-stage reduction mechanism may be employed. Furthermore, the reduction gear is not limited to any one, and includes a rotation shaft, a pair of bearings for supporting the rotation shaft, a pump mechanism for circulating a lubricant, and a cam member attached to the rotation shaft to drive the pump mechanism. The technical idea of the present embodiment can be applied to any rotating device.

(Modification 5)
In the embodiment, the case is described in which the eccentrically oscillating mesh-type reduction mechanism is configured such that the reduction gear casing 74 is fixed and the rotation is output from the carrier body 78, but the present invention is not limited thereto. The speed reduction mechanism may be configured to fix the carrier body 78 and output the rotation from the speed reducer casing 74.

(Modification 6)
Although the embodiment has described that a squirrel cage induction motor is adopted as the motor 12, the type of the motor 12 is not particularly limited. For example, synchronization of an IPM (Interior Permanent Magnet) motor, an SPM (Surface Permanent Magnet) motor, etc. A motor may be employed.

  Combinations of any of the embodiments and variations described above are also useful as embodiments of the present invention. The new embodiments resulting from the combination combine the effects of each of the combined embodiments and variations.

  10 rotating devices, 46 cam members, 48 cam bodies, 82 bearings, 82a inner rings, 82c retainers, 84 bearings, 84a inner rings, 84c retainers, 88 pump mechanisms, 104, 106 high friction members.

Claims (3)

A rotating device comprising: a rotating shaft; a pair of bearings for supporting the rotating shaft; a pump mechanism for circulating a lubricant; and a cam member attached to the rotating shaft for driving the pump mechanism.
The cam member is disposed between the pair of bearings.
A pressing mechanism for pressing the inner ring of the bearing against the cam member;
The cam member is fixed in the circumferential direction with respect to the rotating shaft by being sandwiched by the inner rings of the pair of bearings .
The cam member has a cam body, and a space adjuster disposed between the cam body and the inner ring of the bearing.
The cam body has a cam surface portion having a cam surface, and an annular portion integrated with the cam surface provided on the side opposite to the space adjustment body with respect to the cam surface portion.
The radial thickness of the annular portion is larger than the radial thickness of the space adjusting member . A high friction member is disposed between the cam member and the inner ring of the bearing,
The coefficient of friction between the cam member and the high friction member and between the inner ring of the bearing and the high friction member is larger than the coefficient of friction between the cam member and the inner ring of the bearing. The rotating device according to Item 1. The outer diameter of the portion of the pair of bearings in which the bearing on the cam body side is disposed is larger than the outer diameter of the portion in which the bearing on the interval adjustment body is disposed, and the rotary shaft is viewed from the radial direction The rotating device according to claim 1 or 2 , wherein the retainer of the bearing on the cam body side and the cam body, and the retainer of the bearing on the spacing adjustment body side overlap the spacing adjustment body.

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