JP2021008955A - Carrier of planetary gear device and planetary gear device - Google Patents

Abstract

To reduce the number of assembly man-hours of a planetary gear device by improving the structure of a carrier.SOLUTION: In a carrier 2 of a planetary gear device 1, a gear housing space 12 housing a sun gear 3 and a planetary gear 4 is formed. The gear housing space 12 is formed between a pair of gear support parts 8 and 11 rotatably supporting the planetary gear 4 with a gear support shaft 9. The pair of gear support parts 8 and 11 are integrally connected by a plurality of beams 10. When a virtual plane orthogonal to a rotation axis 6 of the sun gear 3 is an X-Y plane, and directions radially extending from the rotation axis 6 along the X-Y plane are radial directions, the beams 10 are formed along the radial directions at positions outside the sun gear 3 in the radial directions. The planetary gear 4 is located between the beams 10 and 10.SELECTED DRAWING: Figure 2

Description

The present invention relates to a carrier constituting the planetary gear device, and more particularly to a carrier having a structure capable of reducing the number of man-hours for assembling the planetary gear device, and a planetary gear device provided with the carrier.

In general, planetary gears change the rotation transmitted from a drive source such as a motor into a rotation that is convenient for driving other driven devices.

FIG. 14 is a diagram showing a conventional planetary gear device 101. The planetary gear device 101 shown in FIG. 14 supports the sun gear 102 located at the center, three planetary gears (pinion gears) 103 that mesh with the sun gear 102, and each planetary gear 103 so as to rotate, and supports each planetary gear 103 on the sun gear 102. It has a carrier 104 that revolves around the carrier 104. The carrier 104 has a carrier main body 106 on which the support shaft 105 of the planetary gear 103 is formed, and a carrier cover 107 that accommodates the sun gear 102 and the planetary gear 103 between the carrier main body 106. The carrier cover 107 is fixed to the carrier body 106 with a plurality of bolts 108 (see Patent Documents 1 and 2).

Jikkenhei 5-90011 JP-A-2002-13598

However, as shown in FIG. 14, the conventional planetary gear device 101 accommodates the sun gear 102 and the three planetary gears 103 between the carrier main body 106 and the carrier cover 107, and then attaches the carrier cover 107 with a plurality of bolts 108. Since it was fixed to the carrier body 106, the assembly man-hours were increased.

Therefore, an object of the present invention is to provide a carrier having a structure capable of reducing the number of man-hours for assembling the planetary gear device, and a planetary gear device provided with the carrier.

The present invention relates to a carrier 2 of a planetary gear device 1 in which a gear accommodating space 12 for accommodating a sun gear 3 and a planetary gear 4 is formed. In the present invention, the gear accommodating space 12 is formed between a pair of gear support portions 8 and 11 that rotatably support the planetary gear 4 with a gear support shaft 9. Further, the pair of gear support portions 8 and 11 are integrally connected by a plurality of beams 10. Further, it is assumed that the beam 10 has a virtual plane orthogonal to the rotation axis 6 of the sun gear 3 as an XY plane, and a direction extending radially from the rotation axis 6 along the XY plane as a radial direction. , The sun gear 3 is formed along the radial direction at a position outside the radial direction. Further, the planetary gear 4 is located between the beams 10 and 10.

The carrier of the planetary gear device according to the present invention can reduce the man-hours for assembling the planetary gear device as compared with a conventional carrier assembled with a plurality of parts.

It is a figure for demonstrating the carrier of the planetary gear device which concerns on 1st Embodiment of this invention, FIG. 1 (a) is a front view of the carrier, FIG. 1 (b) is a side view of a carrier, FIG. 1 (c). 1 (d) is a rear view of the carrier, FIG. 1 (d) is a cross-sectional view of the carrier cut along the line A2-A2 of FIG. 1 (b), and FIG. 1 (e) is the line A1-A1 of FIG. 1 (a). It is sectional drawing of the carrier shown by cutting along. 2A and 2B are a front view of the planetary gear device, FIG. 2B is a side view of the planetary gear device, and FIG. 2C is a side view of the planetary gear device according to a second embodiment of the present invention. The rear view of the planetary gear device, FIG. 2 (d) is a sectional view of the planetary gear device cut along the A3-A3 line of FIG. 2 (b), and FIG. 2 (e) is a front view of the planetary gear, FIG. (F) is a vertical sectional view of the planetary gear (cross-sectional view of the planetary gear shown by cutting along the A4-A4 line of FIG. 2 (g)), and FIG. 2 (g) is a side view of the planetary gear. It is a figure which shows the carrier of the planetary gear device which concerns on 2nd Embodiment of this invention, FIG. 3 (a) is a front view of a carrier, FIG. 3 (b) is a side view of a carrier, and FIG. A rear view, FIG. 3 (d) is a cross-sectional view of a carrier cut along line A6-A6 of FIG. 3 (b), and FIG. 3 (e) is along line A5-A5 of FIG. 3 (a). It is sectional drawing of the carrier shown by cutting. It is a figure which shows the gear support shaft of the planetary gear device which concerns on 2nd Embodiment of this invention, FIG. 4A is a front view of the gear support shaft, FIG. 4B is a side view of the gear support shaft, FIG. (C) is a rear view of the gear support shaft, and FIG. 4 (d) is an external perspective view showing the gear support shaft viewed from diagonally above the front side. It is a figure which shows the assembly state of the planetary gear device which concerns on 2nd Embodiment of this invention, FIG. 5 (a) is the vertical sectional view of the planetary gear device which shows the 1st assembly state, and FIG. 5 (b) is FIG. FIG. 5 (c) is a cross-sectional view taken along the line A7-A7 of (a), FIG. 5 (c) is a vertical sectional view of a planetary gear device showing a second assembled state, and FIG. 5 (d) is FIG. 5 (c). It is sectional drawing which shows by cutting along the A8-A8 line of. FIG. 6A is a first examination view of an assembly positioning surface in the carrier of the planetary gear device according to the second embodiment of the present invention, and FIG. 6B is a second examination view of the assembly positioning surface. It is a figure which shows the 1st modification of the planetary gear device which concerns on 1st and 2nd Embodiment of this invention simplified, and is the figure which corresponds to FIG. 2 (d). It is a figure which shows the 2nd modification of the planetary gear device which concerns on 1st and 2nd Embodiment of this invention simplified, and is the figure which corresponds to FIG. 2D. It is a figure which shows the 3rd modification of the planetary gear device which concerns on 1st and 2nd Embodiment of this invention simplified, and is the figure which corresponds to FIG. 2 (d). It is a figure which shows the 4th modification of the planetary gear device which concerns on 1st and 2nd Embodiment of this invention simplified, and is the figure which corresponds to FIG. 2 (d). 11A is a front view of the planetary gear device, FIG. 11B is a side view of the planetary gear device, and FIG. 11C is a side view of the planetary gear device according to a third embodiment of the present invention. The rear view of the planetary gear device, FIG. 11 (d), is a cross-sectional view of the planetary gear device shown by cutting along the line A9-A9 of FIG. 11 (b). It is a figure which shows the carrier of the planetary gear device which concerns on 3rd Embodiment of this invention, FIG. 12A is a front view of a carrier, FIG. 12B is a side view of a carrier, and FIG. 12C is a view of a carrier. A rear view, FIG. 12 (d) is a cross-sectional view of a carrier cut along line A11-A11 of FIG. 12 (b), and FIG. 12 (e) is along line A10-A10 of FIG. 12 (a). It is sectional drawing of the carrier shown by cutting. It is a figure which shows the assembly state of a carrier and a planetary gear in the planetary gear device which concerns on 3rd Embodiment of this invention, FIG. 13A is a 1st assembly state diagram, and FIG. 13B is a 2nd assembly state diagram. .. It is a figure which shows the conventional planetary gear device, FIG. 14A is a front view of the planetary gear device, and FIG. 14B is a planetary gear device cut along the lines A12-A12 of FIG. 14 (a). It is a cross-sectional view of.

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

[First Embodiment]
FIG. 1 is a diagram for explaining a carrier 2 of the planetary gear device 1 according to the first embodiment of the present invention. Note that FIG. 1A is a front view of the carrier 2. Further, FIG. 1B is a side view of the carrier 2. Further, FIG. 1C is a rear view of the carrier 2. Further, FIG. 1D is a cross-sectional view of the carrier 2 cut along the line A2-A2 of FIG. 1B. Further, FIG. 1 (e) is a cross-sectional view of the carrier 2 cut along the line A1-A1 of FIG. 1 (a).

As shown in FIG. 1, the planetary gear device 1 supports the sun gear 3 located at the center, three planetary gears (pinion gears) 4 that mesh with the sun gear 3, and each planetary gear 4 so as to rotate and supports each planetary gear 4. It has a carrier 2 that revolves around the sun gear 3. The three planetary gears 4 are arranged at equal intervals along the outer circumference of the sun gear 3. Here, as shown in FIG. 1D, a th-order extending along the Y-axis direction on the XY plane and passing through the rotation axis 6 of the shaft portion 5 of the carrier 2 (rotation axis 6 of the sun gear 3). The planetary gear 4 arranged on the virtual line 7 is appropriately referred to as a first planetary gear 4a. Further, in FIG. 1D, the two planetary gears 4 arranged in order from the first planetary gear 4a in the counterclockwise direction (counterclockwise direction) are appropriately referred to as a second planetary gear 4b and a third planetary gear 4c.

The carrier 2 includes a shaft portion 5 concentric with the rotation shaft center 6 of the sun gear 3, a first gear support portion (first gear support plate) 8 integrally formed at one end of the shaft portion 5, and the first gear. The support portion 8 has a second gear support portion (second gear support plate) 11 integrally formed via a plurality of beams 10. The carrier 2 is formed with a gear accommodating space 12 for accommodating the sun gear 3 and the three planetary gears 4 between the pair of gear support portions (first gear support portion 8 and second gear support portion 11). .. Both the first gear support portion 8 and the second gear support portion 11 are formed in a disk shape, and three pin holes 13 and 14 are formed at equal intervals along the circumferential direction, and each pin hole 13 and A gear support shaft (gear support pin) (not shown) that rotatably supports the planetary gear 4 is inserted into 14. The second gear support portion 11 is formed with a sun gear insertion hole 15 (a hole formed having a diameter larger than the outer diameter of the sun gear 3) for inserting the sun gear 3 into the gear accommodating space 12. Further, the shaft portion 5 is processed according to the usage state of the carrier 2. For example, the shaft portion 5 is formed with teeth that mesh with gears (not shown) on the outer peripheral side, or serration holes are formed along the rotation axis 6.

The beam 10 is formed at three positions so as to be located between the adjacent planetary gears 4 and 4, and the first gear support portion 8 and the second gear support portion 11 are connected to the rotation axis 6 of the shaft portion 5 (the rotation shaft of the sun gear 3). It is integrally connected along the center 6). The beam 10 is outside the radial direction of the sun gear 3 when the virtual plane orthogonal to the rotation axis 6 is the XY plane and the direction extending radially from the rotation axis 6 along the XY plane is the radial direction. From one position (a position on the outer side in the radial direction where a gap is generated between the sun gear 3 and the same diameter as the sun gear insertion hole 15) toward the outer direction in the radial direction (first gear support portion 8 and second gear support portion 8 and second). It is formed in a flat plate shape having a uniform plate thickness (up to the outer end in the radial direction of the gear support portion 11). Here, the beam located between the second planetary gear 4b and the third planetary gear 4c and on the first virtual line 7 is appropriately referred to as the first beam 10a, and is between the first planetary gear 4a and the second planetary gear 4b. The positioned beam 10 is appropriately referred to as a second beam 10b, and the beam 10 located between the first planetary gear 4a and the third planetary gear 4c is appropriately referred to as a third beam 10c. Such first to third beams 10a to 10c are located on radial lines extending in a Y shape on the XY plane and passing through the rotation axis 6 of the sun gear 3.

As shown in FIG. 1 (d), the second beam 10b is clockwise with respect to the second virtual line 16 that passes through the rotation axis 6 of the shaft portion 5 and extends along the XY plane along the X-axis direction. It is tilted by θ in the direction (clockwise). Further, the third beam 10c passes through the rotation axis 6 of the shaft portion 5 and extends in the XY plane along the X-axis direction in the counterclockwise direction (counterclockwise direction) with respect to the second virtual line 16. It is tilted by θ. The second beam 10b and the third beam 10c have a shape symmetrical with respect to the first virtual line 7. Further, since the second beam 10b and the third beam 10c are located close to the second virtual line 16, the first slide piece 17 and the second slide piece 18, which will be described later, can be smoothly moved.

Positioning protrusions (positioning protrusions) 20 are formed on the side surfaces 8a and 11a of the first gear support portion 8 and the second gear support portion 11 so as to correspond to the planetary gear 4. The positioning projections 20 formed on the first gear support portion 8 and the second gear support portion 11 restrict the planetary gear 4 from shifting along the gear support pin (not shown) by abutting on the side surface of the planetary gear 4. By positioning the planetary gear 4 in the direction along the rotation axis 6, the planetary gear 4 and the sun gear 3 are accurately meshed with each other.

The first positioning projection 20 formed corresponding to the first planetary gear 4a is formed from a position outside the radial direction of the sun gear 3 toward the outside in the radial direction and along the first virtual line 7. The shape is line-symmetrical with respect to 1 virtual line 7. Further, the radial inner end of the first positioning protrusion 20 has an arc shape having the same diameter as the outer diameter of the sun gear insertion hole 15 of the second gear support portion 11, and the radial outer end thereof is It is formed in a semicircular shape concentric with the pin holes 13 and 14. The first positioning protrusion 20 has a protrusion surface (convex surface) 20a facing the side surface of the first planetary gear 4a formed in parallel with the XY plane, and the first gear support portion 8 and the second gear support portion 20 are formed. The protrusion side surface (convex side surface) 20b that stands up from each of the facing side surfaces 8a and 11a of 11 and extends to the protrusion surface 20a is formed in parallel with the first virtual line 7. The first positioning protrusion 20 of the first gear support portion 8 and the first positioning protrusion 20 of the second gear support portion 11 have the same shape.

Further, the second positioning projection 20 formed corresponding to the second planetary gear 4b is located between the first planetary gear 4a and the second planetary gear 4b in the direction opposite to the first positioning projection 20 from the second beam 10b. Is formed along the first virtual line 7. The second positioning protrusion 20 has a protrusion surface 20a facing the side surface of the second planetary gear 4b formed in parallel with the XY plane, and the first gear support portion 8 and the second gear support portion 11 face each other. The protrusion side surface 20b that stands up from the side surfaces 8a and 11a and extends to the protrusion surface 20a is formed in parallel with the first virtual line 7. The second positioning protrusion 20 of the first gear support portion 8 and the second positioning protrusion 20 of the second gear support portion 11 have the same shape.

Further, the third positioning projection 20 formed corresponding to the third planetary gear 4c is located between the first planetary gear 4a and the third planetary gear 4c in the direction opposite to that of the first positioning projection 20 from the third beam 10c. Is formed along the first virtual line 7. The third positioning protrusion 20 has a protrusion surface 20a facing the side surface of the third planetary gear 4c formed in parallel with the XY plane, and the first gear support portion 8 and the second gear support portion 11 face each other. The protrusion side surface 20b that stands up from the side surfaces 8a and 11a and extends to the protrusion surface 20a is formed in parallel with the first virtual line 7. The third positioning protrusion 20 of the first gear support portion 8 and the third positioning protrusion 20 of the second gear support portion 11 have the same shape. The second positioning protrusion 20 and the third positioning protrusion 20 have a shape symmetrical with respect to the first virtual line 7.

The carrier 2 having the above structure is formed by injecting a molten resin into a cavity (not shown) of the mold, or by injecting a molten metal into the cavity of the mold. .. At the time of molding the carrier 2, as shown in FIGS. 1 (b) and 1 (d), the second beam 10b, the third beam 10c, and the upper portion on the first positioning projection 20 side are provided in the cavity. The first slide piece 17 to be formed is inserted, and the second positioning protrusion 20, the third positioning protrusion 20, and the second slide piece 18 to form the lower portion on the first beam 10a side are inserted. Then, as shown in FIGS. 1 (b) and 1 (d), the first slide piece 17 and the second slide piece 18 are in the vertical direction (arrow + Y direction, arrow-) from the abutted state after molding. When the slide is moved (released) in the Y direction), the slide movement is not hindered by the first to third positioning protrusions 20 and the first to third beams 10 (10a to 10c), so that the slide is smoothly retracted from the cavity. can do. Therefore, the carrier 2 according to the present embodiment is easily formed by the slide pieces (first slide piece 17 and second slide piece 18) in which the gear accommodating space 12 is divided by two.

As described above, the carrier 2 of the planetary gear device 1 according to the present embodiment has the first positioning protrusions 20 to the third positioning protrusions 20 and the first beam 10 (10a) to the third beam 10 in the gear accommodation space 12. Since (10c) has a shape that does not hinder the slide movement of the first slide piece 17 and the second slide piece 18 forming the gear accommodating space 12, it can be integrally molded in the mold. Therefore, the carrier 2 of the planetary gear device 1 according to the present invention has a plurality of gear support portions (first gear support portion 8 and second gear support portion 11) because they are integrally connected by a plurality of beams 10. As compared with the conventional carrier 104 assembled with the above parts, the number of man-hours for assembling the planetary gear device 1 can be reduced.

[Second Embodiment]
FIG. 2 is a diagram showing a planetary gear device 1 according to the present embodiment. Further, FIG. 3 is a diagram showing a carrier 2 of the planetary gear device 1 according to the present embodiment. In the planetary gear device 1 according to the present embodiment, the components common to the planetary gear device 1 according to the first embodiment are designated by the same reference numerals as the components of the planetary gear device 1 according to the first embodiment. The description overlapping with the planetary gear device 1 according to the embodiment will be omitted as appropriate. Note that FIG. 2A is a front view of the planetary gear device 1. FIG. 2B is a side view of the planetary gear device 1. FIG. 2C is a rear view of the planetary gear device 1. FIG. 2D is a cross-sectional view of the planetary gear device 1 cut along the lines A3-A3 of FIG. 2B. FIG. 2E is a front view of the planetary gear 4. FIG. 2 (f) is a vertical cross-sectional view of the planetary gear 4 (a cross-sectional view of the planetary gear 4 shown by cutting along the A4-A4 line of FIG. 2 (g)). FIG. 2 (g) is a side view of the planetary gear 4. Further, FIG. 3 is a diagram corresponding to FIG.

Similar to the planetary gear device 1 according to the first embodiment, the planetary gear device 1 according to the present embodiment includes a sun gear 3, a plurality of planetary gears 4 (first to third planetary gears 4a to 4c), a carrier 2, and the carrier 2. have. Further, the plurality of planetary gears 4 are adjacent to each other in a gear accommodating space 12 formed between a pair of gear support portions 8 and 11 (first gear support portion 8 and second gear support portion 11) of the carrier 2. It is accommodated in the space between the pair of beams 10 and 10, and is rotatably supported by the pair of gear support portions 8 and 11 by the gear support shaft 9.

The planetary gear 4 is formed with a shaft hole 21 into which the gear support shaft 9 is fitted so as to be relatively rotatable (see FIGS. 4 and 5). A cylindrical overhanging portion 23 is formed on both side surfaces 22 and 22 of the planetary gear 4 and around the shaft hole 21, and the overhanging portion 23 is a gear between the pair of gear supporting portions 8 and 11. It is designed to prevent it from shifting along the support shaft 9. As a result, in the carrier 2 according to the present embodiment, the positioning projection 20 (positioning convex portion) of the carrier 2 according to the first embodiment is omitted, and the facing side surfaces 8a and 11a of the pair of gear support portions 8 and 11 are X. It is a plane parallel to the −Y plane. Further, in the present embodiment, a helical gear is used as the planetary gear 4.

As shown in FIGS. 2 and 3, the plurality of beams 10 (first beam 10a, second beam 10b, third beam 10c) of the carrier 2 are formed around the rotation axis 6 at equal intervals. It is located between the planetary gears 4 and 4. The pair of adjacent beams 10 and 10 are formed so that the projected shape on the XY plane is an inverted C shape (V shape). Further, each beam 10 of the carrier 2 abuts on the tooth tip of the planetary gear 4 accommodated in the gear accommodating space 12, and the assembling positioning surface 24 for positioning the planetary gear 4 at the assembling position to the gear support shaft 9 is provided on the planetary gear 4. Three locations are formed on the opposite side and in the region facing the planetary gear 4 (see FIGS. 5 (a) and 5 (b)). The three assembly positioning surfaces 24 are formed along the radial direction. Further, at least one of the three assembly positioning surfaces 24 is formed with the width dimension W described later. A recess 25 for adjusting the wall thickness of the beam 10 is formed between the assembly positioning surfaces 24 and 24 along the radial direction. As a result, when molding the carrier 2 in the mold, the shrinkage ratio between the beam 10 and the gear support portions 8 and 11 can be adjusted, and the carrier 2 is molded with high accuracy. Further, in the carrier 2 according to the present embodiment, three assembly positioning surfaces 24 are formed on each beam 10, but the present invention is not limited to this, and each assembly positioning surface 24 having a width dimension W described later is formed. At least one location may be formed in the region of the beam 10 facing each planetary gear 4.

FIG. 4 is a diagram showing a gear support shaft 9. The gear support shaft 9 shown in FIG. 4 includes a large diameter portion 28 and a small diameter portion 30 extending from the large diameter portion 28 toward the tip end side. A tapered surface 31 is formed on the tip end side of the small diameter portion 30 of the gear support shaft 9 so that the outer diameter dimension is gradually reduced toward the tip end. The small diameter portion 30 of the gear support shaft 9 is fitted into the pin hole 13 of the first gear support portion 8 and the shaft hole 21 of the planetary gear 4, and rotatably supports the planetary gear 4. Further, the large diameter portion 28 of the gear support shaft 9 is fixed to the second gear support portion 11 by being press-fitted into the pin hole 14 of the second gear support portion 11.

FIG. 5 is a diagram showing an assembled state of the planetary gear device 1 according to the second embodiment of the present invention. Note that FIG. 5A is a vertical cross-sectional view of the planetary gear device 1 showing the first assembled state. FIG. 5B is a cross-sectional view of the planetary gear device 1 cut along the line A7-A7 of FIG. 5A. FIG. 5C is a vertical cross-sectional view of the planetary gear device 1 showing a second assembled state. FIG. 5D is a cross-sectional view of the planetary gear device 1 cut along the line A8-A8 of FIG. 5C.

As shown in the first assembled state of FIGS. 5 (a) and 5 (b), in the planetary gear 4 housed between the pair of beams 10 and 10, the center of the shaft hole 21 is the center of the first gear support portion 8. In a state where the center of the pin hole 13 and the pin hole 14 of the second gear support portion 11 are displaced inward in the radial direction, the tooth tip comes into contact with the assembly positioning surface 24 of the beam 10, and the gear support shaft 9 It is positioned at the assembly position to. A gear support shaft 9 inserted into the shaft hole 21 of the planetary gear 4 positioned at the assembly position by the pair of beams 10 and 10 from the pin hole 14 of the second gear support portion 11 into the gear accommodation space 12. The tapered surface 31 at the tip engages. When the gear support shaft 9 is further pushed into the gear accommodating space 12 from this state, the tapered surface 31 of the gear support shaft 9 enters the shaft hole 21 while moving the planetary gear 4 radially outward to support the gear. The small diameter portion 30 of the shaft 9 engages with the shaft hole 21.

As shown in the second assembled state of FIGS. 5 (c) and 5 (d), the small diameter portion 30 of the gear support shaft 9 is inserted into the shaft hole 21 of the planetary gear 4 and the pin hole 13 of the first gear support portion 8. Then, by press-fitting the large-diameter portion 28 of the gear support shaft 9 into the pin hole 14 of the second gear support portion 11, the planetary gear 4 is positioned along the radial direction of the XY plane (of the planetary gear 4). It is rotatably supported by the gear support shaft 9 (with the center of the shaft hole 21 aligned with the center of the pin hole 13 of the first gear support portion 8 and the center of the pin hole 14 of the second gear support portion 11). ..

FIG. 6A is a first examination view of the assembly positioning surface 24 in the carrier 2 of the planetary gear device 1 according to the second embodiment of the present invention. As shown in FIG. 6A, when the width dimension W of the assembling positioning surface 24 of the beam 10 is larger than the distance along the generatrix direction of the pitch cylinders of adjacent teeth, the assembling positioning surface 24 of the beam 10 is always placed on the tooth tip of the planetary gear 4. The planetary gear 4 can be brought into contact with the gear and can be accurately positioned at the assembly position on the gear support shaft 9.
That is, the width dimension W of the assembly positioning surface 24 is W> (π · D) · cotβ / Z = (π · D) / (assuming that the diameter of the pitch cylinder is D, the twist angle is β, and the number of teeth is Z). It is determined to be Z · tan β).

FIG. 6B is a second examination view of the assembly positioning surface 24 in the carrier 2 of the planetary gear device 1 according to the second embodiment of the present invention. As shown in FIG. 6B, when the assembly positioning surfaces 24 are formed at a plurality of locations (for example, three locations), the distance (L) along the generatrix direction of the pitch cylinders of the adjacent tooth tips of the planetary gears 4 The relationship between / Z), dimension a, and dimension b is shown in FIG. 6 (b-2), where L is the lead of the helical gear, D is the diameter of the pitch cylinder, β is the twist angle, and Z is the number of teeth. ) And FIG. 6 (b-3), the dimensions a to c are determined so as to satisfy the relationship of the following condition (1), and the tooth tip of any of the planetary gears 4 is placed on any of the three assembly positioning surfaces 24. By designing so as to abut, the planetary gear 4 can be accurately positioned at the assembly position on the gear support shaft 9.
a / 2 <L / Z <b ... Condition (1)
L / Z is
L / Z = π ・ D / (Z ・ tanβ) = π ・ D ・ cotβ / Z = W
Can be represented by.

The carrier 2 according to the present embodiment as described above is formed by injecting a molten resin into a cavity (not shown) of the mold, or by injecting a molten metal into the cavity of the mold. It is molded. At the time of molding the carrier 2, as shown in FIGS. 3 (b) and 3 (d), a first slide piece 17 forming an upper portion on the side of the second beam 10b and the third beam 10c is formed in the cavity. At the same time as being inserted, the second slide piece 18 forming the lower portion on the first beam 10a side is inserted. Then, as shown in FIGS. 3 (b) and 3 (d), the first slide piece 17 and the second slide piece 18 are in the vertical direction (arrow + Y direction, arrow-) from the abutted state after molding. When the slide is moved (released) in the Y direction (Y direction), the slide movement is not hindered by the first to third beams 10 (10a to 10c), so that the beam can be smoothly retracted from the cavity. Therefore, the carrier 2 according to the present embodiment is easily formed by the slide pieces (first slide piece 17 and second slide piece 18) in which the gear accommodating space 12 is divided by two. The shaft mold 34 forming the sun gear insertion hole 15 of the second gear support portion 11 can slide and move along the rotation axis 6 of the sun gear 3.

As described above, in the carrier 2 of the planetary gear device 1 according to the present embodiment, the first slide piece in which the first beam 10 (10a) to the third beam 10 (10c) in the gear accommodation space 12 form the gear accommodation space 12. Since the shape does not hinder the slide movement of the 17 and the second slide piece 18, it can be integrally molded in the mold. Therefore, the carrier 2 of the planetary gear device 1 according to the present embodiment has a pair of gear support portions (first gear support portion 8, second gear support portion 11), similarly to the carrier of the planetary gear device according to the first embodiment. ) Are integrally connected by a plurality of beams 10, so that the number of steps for assembling the planetary gear device 1 can be reduced as compared with the conventional carrier 104 assembled by a plurality of parts.

The planetary gear device 1 according to the present embodiment has shown an example in which a helical gear is used as the planetary gear 4, but the present invention is not limited to this, and a spur gear can be used as the planetary gear 4. Further, in the carrier 2 of the planetary gear device 1 according to the present embodiment, a helical gear is formed on the outer peripheral side of the shaft portion 5, but the present invention is not limited to this, and spur gears, splines and the like are formed on the shaft portion 5. It may be formed on the outer peripheral side, or nothing may be formed on the outer peripheral side of the shaft portion.

[First modification]
FIG. 7 is a simplified view showing a first modification of the planetary gear device 1 according to the first and second embodiments of the present invention, and is a diagram corresponding to FIG. 2 (d).

As shown in FIG. 7, the first to fourth beams 10a to 10d of the carrier 2 of the planetary gear device 1 according to the present modification pass through the rotation axis 6 of the sun gear and extend in a cross shape on the XY plane. It is formed on the radial lines 35 and 36, respectively. Further, in this planetary gear device, a pair of adjacent beams 10 and 10 have an inverted C shape (V shape), and a planetary gear 4 is provided in a gear accommodation space between the pair of adjacent beams 10 and 10. It is designed to be placed.

The carrier 2 of such a planetary gear device 1 is formed by injecting a molten resin into a cavity (not shown) of a mold, or by injecting a molten metal into the cavity of a mold. Will be done. At the time of molding the carrier 2, the first slide is divided vertically (+ Y direction and −Y direction) in the cavity by a radial line 35 extending through the rotation axis 6 of the sun gear and along the X axis direction. It is inserted to a position where the piece 17 and the second slide piece 18 are butted against each other. Then, when the first slide piece 17 and the second slide piece 18 are slidably moved (separated) in the vertical direction (arrow + Y direction, arrow-Y direction) from the abutted state after molding, the first slide piece 17 and the second slide piece 18 are first. Since the slide movement is not hindered by the first to fourth beams 10 (10a to 10d), the sliding movement can be smoothly retracted from the cavity. Therefore, the carrier 2 according to the present modification is easily formed by the slide pieces (first slide piece 17 and second slide piece 18) in which the gear accommodating space 12 is divided by two.

[Second modification]
FIG. 8 is a simplified view showing a second modification of the planetary gear device 1 according to the first and second embodiments of the present invention, and is a diagram corresponding to FIG. 2 (d).

As shown in FIG. 8, the planetary gear device 1 according to the present modification halves the planetary gear 4 of the planetary gear device 1 according to the first modification, and two planetary gears 4 are arranged around the rotation axis 6 of the sun gear at equal intervals. It is designed to do. Similar to the carrier 2 according to the first modification, the carrier 2 according to the present modification is easily formed by the slide pieces (first slide piece 17 and second slide piece 18) in which the gear accommodating space 12 is divided into two. To.

[Third variant]
FIG. 9 is a simplified view showing a third modification of the planetary gear device 1 according to the first and second embodiments of the present invention, and is a diagram corresponding to FIG. 2 (d).

As shown in FIG. 9, in the planetary gear device 1 according to the second modification, the planetary gear 4 of the planetary gear device 1 according to the second modification is halved, and one is arranged around the rotation axis 6 of the sun gear. It has become. Similar to the carrier 2 according to the first modification, the carrier 2 according to the present modification is easily formed by the slide pieces (first slide piece 17 and second slide piece 18) in which the gear accommodating space 12 is divided into two. To.

[Fourth variant]
FIG. 10 is a simplified view showing a fourth modification of the planetary gear device 1 according to the first and second embodiments of the present invention, and is a diagram corresponding to FIG. 2 (d).

As shown in FIG. 10, in the planetary gear device 1 according to the present modification, the planetary gear 4 according to the first and second embodiments has three planetary gears 4, whereas the planetary gear 4 is a rotating shaft of the sun gear. One is arranged around the heart 6. Similar to the carrier 2 according to the first and second embodiments, the carrier 2 according to the present modification is easily provided by the slide pieces (first slide piece 17 and second slide piece 18) in which the gear accommodating space 12 is divided by 20. Is molded into.

[Third Embodiment]
FIG. 11 is a diagram showing a planetary gear device according to a third embodiment of the present invention. Further, FIG. 12 is a diagram showing a carrier of the planetary gear device according to the third embodiment of the present invention. The planetary gear device according to the present embodiment is characterized in that, instead of the assembly positioning surface 24 of the planetary gear device according to the second embodiment, a positioning convex portion described in detail later is formed on the gear support portion. The basic configuration of is the same as that of the planetary gear device according to the second embodiment. Therefore, in the planetary gear device according to the present embodiment, the components common to the planetary gear device according to the second embodiment are designated by the same reference numerals as the components of the planetary gear device according to the second embodiment, and the second embodiment. The description overlapping with the planetary gear device according to the above will be omitted as appropriate. Note that FIG. 11A is a front view of the planetary gear device 1. FIG. 11B is a side view of the planetary gear device 1. FIG. 11C is a rear view of the planetary gear device 1. 11 (d) is a cross-sectional view of the planetary gear device 1 cut along the line A9-A9 of FIG. 11 (b). Further, FIG. 12 is a diagram corresponding to FIG.

As shown in FIGS. 11 and 12, the carrier 2 positions the planetary gear 4 at the position where the planetary gear 4 is assembled to the gear support shaft 9 on the side surfaces 8a and 11a of the pair of gear support portions 8 and 11 located on the gear accommodation space 12 side. The positioning convex portion 36 is formed. As shown in FIGS. 2 (e) to 2 (g), the planetary gear 4 has a shaft hole on the side surface facing the gear support portions 8 and 11 and around the shaft hole 21 into which the gear support shaft 9 is fitted. A cylindrical overhanging portion 23 concentric with the center of 21 is formed.

The positioning convex portion 36 is formed so as to extend in the radial direction along the opposite side surfaces of the pair of adjacent beams 10, 10. That is, the positioning convex portion 36 is formed on the side surfaces 8a and 11a of the gear support portions 8 and 11 and at positions along both side surfaces of the beam 10, and is formed together with the beam 10 along the radial direction. The protruding height of the positioning convex portions 36 from the side surfaces 8a and 11a of the gear supporting portions 8 and 11 is smaller than the overhanging length (axial length) of the overhanging portion 23 of the planetary gear 4.

FIG. 13A is a first assembly state diagram of the carrier 2 and the planetary gear 4. As shown in FIG. 13A, the pair of positioning protrusions 36, 36 formed along the opposite side surfaces of the pair of adjacent beams 10, 10 are V-shaped, and the carrier 2 has a V shape. The shape is line-symmetrical with respect to the first virtual line 7 passing through the rotation axis 6. Then, the pair of positioning convex portions 36, 36 abut the side surfaces 36a, 36a on the overhanging portion 23 of the planetary gear 4 accommodated in the gear accommodating space 12, and positions the planetary gear 4 at the assembly position on the gear support shaft 9. It is designed to do. Here, the assembly position is offset inward in the radial direction from the center of the pin hole 13 of the first gear support portion 8 and the center of the pin hole 14 of the second gear support portion 11, but the second When the tapered surface 31 at the tip of the gear support shaft 9 inserted from the pin hole 14 of the gear support portion 11 toward the inside of the gear accommodation space 12 engages and the gear support shaft 9 is further pushed toward the gear accommodation space 12. The tapered surface 31 of the gear support shaft 9 moves the planetary gear 4 outward in the radial direction, and the small diameter portion 30 of the gear support shaft 9 is engaged with the shaft hole 21 of the planetary gear 4 (see FIG. 5). ..

FIG. 13B is a second assembly state diagram of the carrier 2 and the planetary gear 4, in which the small diameter portion 30 of the gear support shaft 9 is engaged with the pin hole 13 of the first gear support portion 8 and the planetary gear 4 is engaged. The large diameter portion 28 of the gear support shaft 9 is press-fitted into the pin hole 14 of the second gear support portion 11 by being engaged with the shaft hole 21 of the above, so that the planetary gear 4 can rotate to the meshing position with the sun gear 3. It is a figure which shows the supported state. As shown in FIG. 13B, the planetary gear 4 is rotatably supported by the gear support shaft 9 at the meshing position with the sun gear 3, so that the planetary gear 4 is separated from the positioning convex portion 36 and slides with the positioning convex portion 36. It can rotate smoothly without touching.

The carrier 2 of the planetary gear device 1 according to the present embodiment as described above is the same as the carrier 2 of the planetary gear device 1 according to the second embodiment, from the first beam 10 (10a) in the gear accommodating space 12. Since the three beams 10 (10c) and each positioning convex portion 36 have a shape that does not hinder the slide movement of the first slide piece 17 and the second slide piece 18 forming the gear accommodating space 12, they are integrally molded in the mold. Will be possible. Therefore, the carrier 2 of the planetary gear device 1 according to the present embodiment has a pair of gear support portions (first gear support portion 8, second gear) similar to the carrier of the planetary gear device according to the first and second embodiments. Since the support portion 11) is integrally connected by the plurality of beams 10, the number of steps for assembling the planetary gear device 1 can be reduced as compared with the conventional carrier 104 assembled by a plurality of parts.

The first to fourth modifications of the planetary gear device 1 according to the first and second embodiments of the present invention can also be applied to the planetary gear device 1 according to the third embodiment of the present invention.

1 ... Planetary gear device, 2 ... Carrier, 3 ... Sun gear, 4 ... Planetary gear (pinion gear), 6 ... Rotation axis, 8 ... 1st gear support (1st gear support plate), 9 ... ... Gear support shaft, 10 ... Beam, 11 ... Second gear support (second gear support plate), 12 ... Gear accommodation space

Claims (8)

In a carrier of a planetary gear device in which a gear accommodating space for accommodating a sun gear and a planetary gear is formed.
The gear accommodating space is formed between a pair of gear support portions that rotatably support the planetary gear on a gear support shaft.
The pair of gear supports are integrally connected by a plurality of beams, and are integrally connected.
Assuming that the virtual plane orthogonal to the rotation axis of the sun gear is the XY plane and the direction extending radially from the rotation axis along the XY plane is the radial direction, the beam is the radial direction of the sun gear. Formed at the outer position along the radial direction,
The planetary gear is located between the beams.
A carrier of a planetary gear device characterized by that. The plurality of beams are each formed on a radial line extending in a Y shape on the XY plane and passing through the rotation axis of the sun gear.
The carrier of the planetary gear device according to claim 1. Each of the plurality of beams is formed on a radial line extending in a cross shape on the XY plane and passing through the rotation axis of the sun gear.
The carrier of the planetary gear device according to claim 1. A plurality of the planetary gears are arranged between the adjacent beams.
The carrier of the planetary gear device according to any one of claims 1 to 3. The beam abuts on the tooth tip of the planetary gear accommodated in the gear accommodating space, and the assembly positioning surface for positioning the planetary gear at the assembly position on the gear support shaft is on the side facing the planetary gear and on the planetary gear. At least one location formed in the opposite region,
The carrier of the planetary gear device according to any one of claims 1 to 4, wherein the carrier is a planetary gear device. The planetary gear has a cylindrical overhang portion formed on a side surface facing the gear support portion and around a shaft hole into which the gear support shaft is fitted.
Positioning of the gear support portion located on the side of the gear accommodating space abuts on the overhanging portion of the planetary gear accommodated in the gear accommodating space and positions the planetary gear at an assembly position on the support shaft. The convex portion is formed so as to extend in the radial direction along the opposite side surfaces of the pair of adjacent beams.
The carrier of the planetary gear device according to any one of claims 1 to 3, wherein the carrier is a planetary gear device. Three planetary gears are arranged,
The beam is located between the adjacent planetary gears and is formed in a flat plate shape along the radial direction.
On the facing side surfaces of the pair of gear support portions, a positioning convex portion corresponding to the planetary gear is formed to regulate the movement of the planetary gear along the gear support shaft by abutting against the side surface of the planetary gear.
Assuming that one planetary gear is located on a virtual line extending along the Y-axis direction on the XY plane and passing through the rotation axis of the sun gear, and the planetary gear located on the virtual line is the first planetary gear. The first positioning protrusion formed corresponding to the first planetary gear is formed from the radial outer position of the sun gear further radially outward and along the virtual line.
In the positioning convex portion, the convex portion surface facing the side surface of the planetary gear is formed parallel to the XY plane, and the convex portion side surface that stands up from the side surface of the gear support portion and extends to the convex portion surface is said. Formed parallel to the virtual line,
When the two planetary gears other than the first planetary gear are the second planetary gear and the third planetary gear, the second and third positioning convex portions formed corresponding to the second planetary gear and the third planetary gear, respectively. Is formed from the beam in the direction opposite to the first positioning convex portion along the virtual line.
The beam located between the second planetary gear and the third planetary gear is located along the virtual line.
The carrier of the planetary gear device according to claim 2. The carrier of the planetary gear device according to any one of claims 1 to 7.
The planetary gear accommodated in the gear accommodating space of the carrier and rotatably supported by the pair of gear support portions by the gear support shaft.
A planetary gear device characterized by being equipped with.

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