JP4588586B2 - Simple planetary gear mechanism planetary gear unit series - Google Patents

Description

The present invention relates to a planetary gear instrumentation 置Shi Leeds simple planetary gear mechanism.

  The simple planetary gear mechanism includes a sun gear, a planetary gear that is supported by a carrier pin supported by a carrier and circumscribes the sun gear, and an internal gear that is inscribed by the planetary gear. This simple planetary gear mechanism is widely used for various applications because of concentric input / output and high transmission efficiency.

  Specifically, a planetary gear device using a simple planetary gear mechanism as described in Patent Document 1 is known.

  FIG. 5 shows a planetary gear device 12 described in Patent Document 1.

  The planetary gear device 12 is configured to receive rotation of a motor shaft (not shown) of a motor that is a power source by an input shaft 18, decelerate, and transmit the rotation to an output shaft 32 via a carrier 30.

  In the market, there is a demand for diversification of the reduction gear ratio, and in such a planetary gear device 12, it is necessary to prepare various reduction gear ratios in advance. In such a case, as shown in FIG. 6, the internal gear 34 is common in order to maintain the compactness of the entire apparatus, and the size of the sun gear 22 and the planetary gear 24 is changed as appropriate so that variations in the reduction ratio can be achieved. Is configured. Note that when the sizes of the sun gear 22 and the planetary gear 24 are appropriately changed in this way so that variations in the reduction ratio are made uniform, the track of the carrier pin 26 (the revolution trajectory during operation) is also changed accordingly. (Refer to FIG. 6, C1 to C3). As a result, the carrier 30 must be prepared for each reduction ratio.

JP 2002-188893 A

  If the planetary gear device is configured to be applied to various reduction ratios by the method as in the conventional example, it means that the total number of parts increases, and accordingly, the total inventory amount increases, Since the number of production per lot part decreases, the part cost increases.

  The present invention has been made in view of such conventional problems, and in a planetary gear device, a common carrier is realized, and a series of planetary gear devices with different reduction ratios using a common carrier. The main challenge is to provide it.

The present invention relates to a simple planetary gear mechanism having different reduction ratios , comprising a sun gear, a planetary gear that is supported by a carrier pin supported by a carrier and circumscribes the sun gear, and an internal gear that is inscribed by the planetary gear. In the planetary gear device series , the carrier pin includes a crank portion that is eccentric with respect to the axis of the carrier pin, and the planetary gear is rotatably supported around the axis of the crank portion. At the same time, the amount of eccentricity from the axial center position of the carrier pin to the axial center position of the crank portion is a diameter ratio of the crank portion of 0.1 to 0.3 , and the carrier is shared between series. The above-mentioned problems are solved.

  In the present invention, the carrier pin that supports the planetary gear is not a simple cylindrical shape, but includes a crank portion that is eccentric with respect to the axis of the carrier pin. The planetary gear is rotatably supported by a crank part having an axis that is eccentric with respect to the axis of the carrier pin (with the axis of the crank part as the center of rotation).

  As a result, the axial center position of the crank portion can be freely adjusted for planetary gears of various sizes, and multiple types of planetary gears having different pitch circles can be connected to the internal gear with carrier pins of the same axial center position. Can be touched.

  The fact that the axial center position of the carrier pin can be kept the same means that the carrier, which is a member connected to the carrier pin, can be kept the same, and the sharing of the parts of the entire apparatus can be greatly facilitated.

  In the present invention, the eccentric amount from the axial center position of the carrier pin to the axial center position of the crank portion is set to be in a range of 0.1 to 0.3 with respect to the diameter of the crank portion.

  This is because when the amount of eccentricity is less than 0.1 with respect to the diameter of the crank portion, the types of planetary gears that can be incorporated are reduced, and the original effect intended by the present invention of “promoting commonality” is obtained. This is because it will disappear. It is to be noted that a planetary gear or the like is manufactured by providing a slight eccentricity that is less than 0.1 with respect to the diameter of the crank portion as the amount of eccentricity from the axial position of the carrier pin to the axial position of the crank portion. Although it is possible to absorb the error, the present invention solves the problem of “promotion of commonality” peculiar to the present invention by deliberately setting an amount of eccentricity above a certain level.

  From the same viewpoint, the amount of eccentricity from the axial center position of the carrier pin to the axial center position of the crank portion should be set in a range of the carrier pin diameter ratio of 0.15 to 0.5.

  It is to be noted that the eccentric amount is set in these common ranges, that is, the diameter ratio of the crank portion is 0.1 to 0.3 and the diameter ratio of the carrier pin is 0.15 to 0.5. Even better.

  According to the present invention, it is possible to reduce the cost of parts by reducing the total number of parts, reducing the total inventory, and increasing the number of production per lot.

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

FIG. 1 is a schematic longitudinal sectional view of a geared motor GM110 to which a planetary gear device employed in a planetary gear device series according to the present invention is applied.

  The geared motor GM110 includes a motor 114 and a planetary gear unit 112.

  The simple planetary gear mechanism S1 of the planetary gear device 112 includes a sun gear 122, three planetary gears 124 circumscribing the sun gear 122, and an internal gear 134 inscribed by the planetary gear 124.

  The sun gear 122 is press-fitted into the input shaft 118. The input shaft 118 has an insertion hole 118A into which the motor shaft 116 of the motor 114 is inserted. With the motor shaft 116 inserted into the insertion hole 118A, a fastening bolt (not shown) is screwed into the screw portion 119. Thus, the input shaft 118 and the motor shaft 116 are frictionally coupled by the generated fastening force.

  The motor 114 is connected to the joint cover 140 via a connecting bolt hole 140A, and the joint cover 140 is connected to the casing 138 of the planetary gear unit 112 via a bolt 136.

  The planetary gear 124 is rotatably supported via a carrier pin 126 supported by the carrier 130. The structure around the carrier pin 126 will be described in detail later.

  The carrier 130 is rotatably supported by the casing 138 via bearings 144 and 146, and is disposed between the three planetary gears 124 which are provided upright on the thick disk-shaped main body plate 130A and the main body plate 130A. It is mainly composed of three positioned columns 130B and a cover plate 130C connected to the end surface of the column 130B via bolts 142.

  An output shaft 132 is integrated with the main body plate 130 </ b> A of the carrier 130, and the rotation of the carrier 130 is taken out as rotation of the output shaft 132.

  The internal gear 134 is formed integrally with the casing 138. The casing 138 is fixed to an external fixing member (not shown) through the mounting hole 138A.

  Therefore, this planetary gear unit 112 includes a simple planetary gear mechanism of sun gear input, internal gear fixed, and carrier output.

  Here, the support structure of the planetary gear 124 which is the greatest feature of this embodiment will be described in detail.

  FIG. 2 is a diagram showing a relationship among the internal gear 134, the sun gear 122, and the planetary gear 124 in a cross section taken along the line II-II in FIG. 1. When (A) has a large reduction ratio, (B) When the reduction ratio is medium, (C) shows the case where the reduction ratio is small.

  2 to 4 (FIG. 4 is a conceptual diagram), three planetary gears 124 are provided and supported by carrier pins 126 that are rotatably supported by the carrier 130, respectively. The carrier pin 126 is provided with an eccentric cam that is eccentric with respect to the axis Po of the carrier pin 126 so as to be integrated in the rotation direction, and a crank portion 152 is formed. As a result, the eccentric direction (eccentric angle α) of the axis Co of the crank portion 152 relative to the axis Po of the carrier pin 126 is variable while the carrier pin 126 is supported by the carrier 130. Here, the “eccentric angle α” is a reference eccentric direction (a direction serving as a reference for the direction in which the crank portion axis is eccentric = a straight line connecting the carrier pin axis Po and the crank portion axis Co). , A tangent line at the intersection of a circle drawn by the carrier pin axis Po when the carrier pin revolves) and an angle formed by a straight line connecting the axis of the carrier pin and the axis of the crank portion. . In addition, although this reference | standard eccentric direction Ta is made to correspond with a tangent direction in this example, it does not necessarily need to make it correspond completely. The crank portion 152 is swung by an eccentric angle α about the axis Po of the carrier pin 126 with reference to the reference eccentric direction, so that the position of the axis Co of the crank portion 152 is changed in the circumferential direction (of the carrier pin 126). It is possible to rotate in the circumferential direction around the axis Po.

  The planetary gear 124 is supported rotatably about the axis Co of the crank portion 152 as a rotation center.

  More specifically, an eccentric cam 150 is provided on the outer periphery at the center in the axial direction of the carrier pin 126 as a crank portion and shifted by an eccentric amount e from the axis Po of the carrier pin 126. The eccentric cam 150 rotatably supports the planetary gear 124 (via a bearing 151) on its outer periphery. The eccentric cam 150 is integrated with the carrier pin 126 in the rotational direction.

  Further, the carrier pin 126 itself is rotatably supported by a hole 130D formed in the main body plate 130A of the carrier 130 and a hole 130E formed in the cover plate 130C (see FIG. 1).

  In other words, the carrier pin 126 includes a crank portion 152 that is eccentric by an eccentric amount e with respect to the shaft center Po of the carrier pin 126, and the position of the shaft center Co of the crank portion 152 is the carrier This means that the pin 126 can rotate in the circumferential direction around the position of the axis Po of the pin 126, and the planetary gear 124 is supported rotatably about the axis Co of the crank portion 152 as the center of rotation. .

  Next, the operation of the geared motor GM110 including the planetary gear device 112 will be described.

  When the motor 114 is energized, the motor shaft 116 rotates, and the input shaft 118 and the sun gear 122 also rotate accordingly.

  The rotation of the sun gear 122 rotates the meshing planetary gear 124. Since the planetary gear 124 meshes with the sun gear 122 and also with the internal gear 134, the planetary gear 124 revolves slowly while rotating around the sun gear 122. By taking out this slow revolution component through the carrier 130, the rotation of the input motor shaft 116 is decelerated and output to the output shaft 132.

  The reduction ratio at this time is (the number of teeth of the sun gear 122 + the number of teeth of the internal gear 134) / (the number of teeth of the sun gear 122), and the gear ratio of both the gears 122 and 134 is adjusted. Thus, the reduction ratio can be adjusted.

  A description will be given based on a configuration example for obtaining a moderate reduction ratio (about 5 in this case) as shown in FIG. 2B. In operation, the center Co of the crank portion 152 (the center of the eccentric cam 150, and further, The trajectory C5 through which the planetary gear 124 rotates) and the trajectory through which the axis Po of the carrier pin passes substantially coincide, and the eccentric angle α2 is a value close to approximately 180 °.

  Here, the reason that the reference eccentric direction Ta of the crank portion 152 of each carrier pin 126 is aligned in the same direction (all directions on the R side in the illustrated example) is the radius generated in each planetary gear 124. This is because the directions of the moments in the direction (the push-out direction toward the outer peripheral side or the pull-in direction toward the inner peripheral side) can be made uniform, and as a result, the moments on the entire circumference can be easily canceled out.

  On the other hand, when the gear device 112 having a large reduction gear ratio is configured using the same internal gear 134, the gear device 112 is as shown in FIG. 2A (here, the reduction gear ratio 9).

  In order to obtain a large reduction ratio, the sun gear 122 is small and its number of teeth is reduced, and the planetary gear 124 is enlarged to compensate for it. With the change in the configuration, the trajectory C4 of the axial center Co of the crank portion 152 is positioned more inward (on the sun gear 122 side) as compared with the above-described medium reduction ratio (FIG. 2B). To do.

  If the present invention is not applied, the change in the trajectory (C5 → C4) is exactly the change in the trajectory of the carrier pin, so two types of carriers supporting the carrier pin must be prepared. Therefore, the number of parts inevitably increases.

  However, by applying the present invention, as shown in FIG. 2A, the crank portion 152 is rotated with respect to the axis of the carrier pin at an eccentric angle α1, so that the crank portion 152 is rotated. Even if the axis Co of the rotation of the planetary gear 124 changes, the trajectory of the axis Po of the carrier pin 126 does not change (is still C5) and can rotate. This means that even when the reduction ratio is changed within a certain range (the reduction ratio is increased), it is possible to use a single type of carrier 130 (common carrier). ing.

  The same applies to the case where a planetary gear device having a smaller reduction gear ratio is configured (see FIG. 2C, here, the reduction gear ratio is about 3.67). That is, even when the trajectory C6 of the shaft center Co of the crank portion becomes large within a certain range (toward the internal gear 134), the crank portion 152 is rotated at an eccentric angle α3. This change can be absorbed.

  As shown in FIG. 3, the eccentric amount e between the axis Po of the carrier pin and the axis Co of the crank portion 152 (eccentric cam 150) is set so as to satisfy any of the following conditions.

  The first condition is that the eccentricity e is a ratio of the diameter D of the crank portion 152 (the diameter of the eccentric cam 150) of 0.1 to 0.3.

  This is because when the amount of eccentricity is less than 0.1 with respect to the diameter of the crank portion, the types of planetary gears that can be incorporated are reduced, and the original effect intended by the present invention of “promoting commonality” is obtained. This is because it will disappear. Conversely, the larger the amount of eccentricity, the greater the reduction ratio that can be accommodated by one carrier. However, in reality, when the amount of eccentricity is 0.3 or more with respect to the diameter of the crank part, it becomes difficult to incorporate the planetary gear. Or a radial moment applied to the crankshaft increases, which is undesirable.

  The second condition is that the amount of eccentricity e is a diameter d ratio of the carrier pin 126 of 0.15 to 0.5.

  Similarly to the above, when the amount of eccentricity is less than 0.15 with respect to the diameter of the carrier pin, the number of types of planetary gears that can be incorporated is reduced, and the original intention of the present invention “promoting commonality” This is because a special effect cannot be obtained. Conversely, the larger the amount of eccentricity, the more the reduction gear ratio can be accommodated with one carrier. However, in reality, when the amount of eccentricity is 0.5 or more with respect to the diameter of the carrier pin, it becomes difficult to incorporate the planetary gear. Or a radial moment applied to the crankshaft increases, which is not preferable.

  It is more preferable that both the first and second conditions are satisfied.

  The eccentricity e is a minimum diameter PCDmin (corresponding to PCD4 in FIG. 2A) in the configuration of the maximum reduction ratio to share the carrier and the axis Co of the crank portion. This is a value obtained by dividing the difference from the diameter PCDmax (corresponding to PCD6 of (C) in FIG. 2) by 2 in the configuration of the reduction gear ratio.

  In the present invention, how the crank portion is specifically formed is not particularly limited, and various configurations can be employed.

  For example, as described above, when an eccentric cam capable of rotatably supporting the planetary gear is "integrated in the rotational direction" on the carrier pin, it may be formed as a single unit, and a plurality of members are combined. As a result, it may be integrated in the rotational direction. Further, the crank portion of the carrier pin can be formed by incorporating an eccentric cam capable of rotatably supporting the planetary gear on the outer periphery of the carrier pin so as to be rotatable with respect to the carrier pin. When the carrier pin is “supported rotatably” on the carrier, a bearing or the like may be interposed between them.

  In the above embodiment, the reference eccentric direction Ta of each planetary gear is directed to the same side with respect to a straight line connecting the axis of the simple planetary gear mechanism and the axis of the carrier pin.

  This is because in the present invention, the planetary gear is pushed out or pulled inward due to the shift of the axis of the carrier pin and the rotational center of the planetary gear in each planetary gear in the present invention. This is because a moment (a radial force) to be generated may be generated. However, in the present invention, it is not always required to maintain the reference eccentric direction of the carrier pins of all the planetary gears on the same side.

  For example, in order to minimize the difference in the effect in the forward and reverse directions with respect to the generation of this moment, the even number of planetary gears is provided, and the reference eccentric direction of the adjacent crank portion is the same as that of the axis of the simple planetary gear mechanism. It is preferable to be directed alternately to the opposite side with respect to the straight line connecting the axis of the crank portion.

  That is, the force that pushes the planetary gear outward or pulls it inward is reversed between forward rotation and reverse rotation. Therefore, in order to reduce the difference in the influence of the moment in forward rotation and reverse rotation, it is reasonable to assemble with a correspondence that stochastically equalizes the behavior during forward rotation and the behavior during reverse rotation.

  In the case of the above embodiment, the crank portion has an automatic alignment function. By this function, for example, even during operation, an advantage is obtained that the torque relationship (the torque relationship in the radial direction) of the internal gear, the planetary gear, and the sun gear at that time is maintained in a balanced state. Therefore, when the sun gear is incorporated in a float state (a state where the shaft center can be slightly changed with respect to the shaft center Ro of the speed reducer: for example, a coupled state by a spline), all the planetary gears A state in which the radial torque relationships are balanced with each other is maintained in real time. In particular, when the number of planetary gears is three, it is possible to operate in a state where the torque relation in the radial direction of all planetary gears is always perfectly balanced, and this is a great advantage depending on the application. obtain.

  Conversely, the carrier pin and the crank portion may be configured to be fixed to the carrier so that the self-aligning function is intentionally disabled once the integration is completed in the optimum situation. This is because, for example, when used for an application that rotates at high speed, smooth rotation and support are possible even if there is a slight manufacturing variation.

  In the present invention, when the carrier pin and the crank part are fixed to the carrier, the axis of the crank part in the fixed state is the same as the “normal” simple planetary gear mechanism corresponding to the axis of the conventional carrier pin. It becomes the composition of.

  By applying the present invention in this way, it is possible to expect a reduction in parts cost due to a reduction in the total number of parts, a reduction in the total inventory, and an increase in the number of production per lot.

  The present invention can be widely used as a transmission including the geared motor shown as the embodiment.

Schematic longitudinal sectional view of a geared motor GM110 to which a planetary gear device employed in a planetary gear device series according to the present invention is applied. FIG. 1A shows the relationship between the internal gear, the sun gear, and the planetary gear in the cross section taken along the line II-II in FIG. 1. FIG. 1B shows a case where the reduction ratio is large, FIG. Is a diagram showing a small reduction ratio It is an enlarged view of the carrier pin provided with the eccentric cam, (A) is a side view, (B) is a front view. The figure which showed the positional relationship of a sun gear, a planetary gear, and a carrier pin in each reduction ratio shown in FIG. Sectional drawing of geared motor GM10 provided with the planetary gear apparatus substantially the same as the planetary gear apparatus of patent document 1 FIG. 5A shows the relationship between the internal gear, the sun gear, and the planetary gear in the cross-section along the line VI-VI in FIG. 5. FIG. 5A shows a large reduction ratio, FIG. 5B shows a medium reduction ratio. Is a diagram showing a small reduction ratio

Explanation of symbols

GM110 ... Geared motor S1 ... Simple planetary gear mechanism 112 ... Planetary gear unit 118 ... Input shaft 122 ... Sun gear 124 ... Planetary gear 126 ... Carrier pin 130 ... Carrier 134 ... Internal gear 138 ... Casing 140 ... Joint cover 150 ... Eccentric cam 152 ... Crank part Ro ... Center of reduction gear (simple planetary gear mechanism) Po ... Center of carrier pin Co ... Center of crank part (eccentric cam) Ta ... Reference eccentricity e ... Eccentricity α ... Eccentric angle

Claims (3)

A planetary gear device of a simple planetary gear mechanism having different reduction ratios, comprising a sun gear, a planetary gear supported by a carrier pin supported by a carrier and circumscribed with the sun gear, and an internal gear with which the planetary gear is inscribed In the series,
The carrier pin includes a crank portion that is eccentric with respect to the axis of the carrier pin;
The planetary gear is supported rotatably about the axis of the crank portion as a center of rotation, and the amount of eccentricity from the axis position of the carrier pin to the axis position of the crank portion is a ratio of the diameter of the crank portion. A planetary gear unit series of a simple planetary gear mechanism, wherein the carrier is common between series. A planetary gear device of a simple planetary gear mechanism having different reduction ratios, comprising a sun gear, a planetary gear supported by a carrier pin supported by a carrier and circumscribed with the sun gear, and an internal gear with which the planetary gear is inscribed In the series,
The carrier pin includes a crank portion that is eccentric with respect to the axis of the carrier pin;
The planetary gear is supported rotatably about the axis of the crank portion as a center of rotation, and the amount of eccentricity from the axis position of the carrier pin to the axis position of the crank portion is the ratio of the diameter of the carrier pin. A planetary gear unit series of a simple planetary gear mechanism, wherein the carrier is common between series. A planetary gear device of a simple planetary gear mechanism having different reduction ratios, comprising a sun gear, a planetary gear supported by a carrier pin supported by a carrier and circumscribed with the sun gear, and an internal gear with which the planetary gear is inscribed In the series,
The carrier pin includes a crank portion that is eccentric with respect to the axis of the carrier pin;
The planetary gear is supported rotatably about the axis of the crank portion as a center of rotation, and the amount of eccentricity from the axis position of the carrier pin to the axis position of the crank portion is a ratio of the diameter of the crank portion. The planetary gear of a simple planetary gear mechanism, wherein the carrier pin has a diameter ratio of 0.1 to 0.3 and a carrier pin diameter ratio of 0.15 to 0.5. Equipment series.

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