JPH0665653U - Reduction gears with balls arranged on the epitrochoidal curved surface on the outer circumference of the planetary disk - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a speed reducer with a small loss of rotational torque during deceleration. [Structure] A speed reducer 50 has a casing 51 that rotatably supports the input and output shafts 52, 53 so as to abut each other.
And a wavy epitrochoidal curved surface 56 formed on the outer periphery of a planetary disk 54 eccentrically supported by the input shaft 52 and rotatably supported, and an axial center C1 of the input shaft 52 opposed to the epitrochoidal curved surface 56. The number of waves on the hypotrochoidal curved surface 57, which is provided in the casing 51 centering on the center of the curve, and the number of waves on the hypotrochoidal curved surface 57, which is sandwiched between the two curved surfaces 56 and 57, are greater than the number of waves on the hypotrochoidal curved surface 57. The output shaft 5 has a small number of balls 55, a pin 79 protruding from the planetary disc 54, and a pin 79 inserted between the pin 79 and the pin 79 to allow a eccentric movement of the planetary disc 54.
3 has a pin insertion hole 89 formed therein. The ball 55 receives a tangential force from the planetary disc 54 and rolls on the outer periphery of the planetary disc 54.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a speed reducer in which balls are arranged on an epitrochoid curved surface on the outer circumference of a planetary disk.

[0002]

[Prior art]

 Conventionally, there is a speed reducer using a ball as a torque transmitting element as shown in FIGS. 14 and 15. This decelerator 20 includes a drive shaft 22 having an eccentric cam 21 having an eccentric distance e, a ball type Oldham mechanism 23 such as an old joint, and a ring formed on the eccentric cam 21 in which a hypocycloid curve groove 24 is formed. -Shaped eccentric plate 25, a driven disk 27 having an epicycloidal curve groove 26 having an even number of waves smaller than the number of waves of the hypocycloidal curve groove 24, and a driven shaft 28 integral with the driven disk 27. It consists of and. The eccentric plate 25 and the driven disc 27 face each other via a ball 29. The drive shaft 22 and the driven shaft 28 are rotatably supported by the casing 38 with their axes aligned.

The ball type Oldham mechanism 23 (see FIG. 15) includes a fixed disc 30 forming a part of the casing 38, a slider 31 facing the fixed disc 30, and six fixed discs 30 on the fixed disc 30. The six laterally moving balls 32 sandwiched between the lateral groove 34 and the six lateral grooves 35 on the slider 31, the six longitudinal grooves 36 on the slider 31, and the six longitudinal grooves 37 on the eccentric plate 25. It is composed of six vertically-moving balls 33 which are sandwiched.

When the drive shaft 22 is rotated, the slider 31 of the ball-type Oldham mechanism 23 simultaneously moves vertically and horizontally by using the grooves 34, 35, 36 and 37 and the balls 32 and 33 as guides, and the eccentric plate. The rotation of 25 is restricted and the revolution is permitted. The eccentric plate 25 revolves while drawing a circle having a radius e by the cam 21 while the rotation of the eccentric plate 25 is restricted by the slider 31. That is, the eccentric plate 25 makes an eccentric movement. When the eccentric plate 25 revolves by the number of waves of the hypocycloid curve groove 24, the driven disk 27 causes the number of waves of the hypocycloid curve groove 24 and the number of waves of the epicycloid curve groove 26 by the epicycloid curve groove 26 and the ball 29. It is rotated by the difference in the number of waves.

In the speed reducer 20, the hypocycloidal curved groove 24 and the epicycloidal curved groove 26 are formed on the facing surfaces 39 and 40 of the eccentric disc 25 and the driven disc 27, respectively. The ball 25 and the epicycloidal curved groove 26 are driven and arranged in the axial direction of the driven shafts 22 and 25. Therefore, in FIG. 14, when attention is focused on the upper ball 29, the rotational torque transmitted to the epicycloidal curved groove 26 while rotating in a direction in which the ball 29 floats above the paper surface is indicated by an arrow A direction (the tip of the arrow A). Shall be lifted from the paper.). As a result, slippage may occur between the grooves 24 and 26 and the ball 29, or the edge 41 of the epicycloid curve groove 26 may be chipped.

In order to prevent such a fear, the curved grooves 24, 26 and other parts are shaped and dimensioned such that the torque transmission direction (direction of arrow A in FIG. 14) is about 45 degrees with respect to the facing surface 40. (The rising angle of the arrow A with respect to the paper surface is also set to about 45 degrees.) To prevent the occurrence of slips and defects.

[0007]

[Problems to be solved by the device]

 However, such a speed reducer 20 has the following problems. (1) Since torque is transmitted to the epicycloidal curved groove 26 in the direction of arrow A, torque crossing occurs and torque transmission efficiency is poor (rotation torque is most lost when applied to the outer circumference of the driven disk 27 in the tangential direction). Few.). (2) Since the ball 29 is engaged with the epicycloidal curve groove 26 in a state of being caught by the edge 41, the contact area between the ball 29 and the epicycloidal curve groove 26 is small, and the ball 29 and the epicycloid curve are The groove 26 is easily worn. (3) When the epicycloidal curved groove 26 and the ball 29 are worn, the accuracy of the reduction ratio is reduced. (4) Since the drive shaft 22 and the eccentric plate 25 are supported by the bearings 42 and 43, the precision of the reduction gear ratio cannot be improved due to the rattling of the bearings 42 and 43 themselves.

[0008]

[Means for Solving the Problems]

 The present invention is, firstly, a casing for rotatably supporting an input shaft and an output shaft so as to abut against each other with a space therebetween, a planetary disk eccentrically supported by the input shaft and rotatably supported, A wavy epitrochoidal curved surface formed on the outer circumference of the planetary disk, and a wavy hypotrochoidal curved surface facing the epitrochoidal curved surface and provided inside the casing about the axis of the input shaft. A ball sandwiched between the epitrochoid curved surface and the hypotrochoid curved surface and less than the number of waves on the epitrochoid curved surface and less than the number of waves on the hypotrochoid curved surface; A plurality of pins that are provided between the input shaft and the output shaft and that are parallel to the output shaft, and a pin that has a gap between the pins and that allows eccentric movement of the planetary disk between the pins. Secondly, by a speed reducer having a hole, a casing that rotatably supports the input shaft and the output shaft so as to abut against each other at an interval, and the input shaft that is eccentrically rotatably supported. A planetary disk whose outer diameter on the shaft side is larger than the outer diameter on the output shaft side, a wavy epitrochoidal curved surface formed on the outer periphery of the planetary disk, and a surface facing the epitrochoidal curved surface and the input A corrugated hypotrochoidal curved surface formed in a hole having the inner diameter on the input shaft side larger than the inner diameter on the output shaft side, which is provided inside the casing around the axis of the shaft, and the epitrochoidal curved surface. Between the ball sandwiched between the hypotrochoidal curved surface and less than the number of waves on the epitrochoidal curved surface and less than the number of waves on the hypotrochoidal curved surface, between the planetary disk and the output shaft. A plurality of pins parallel to the input and output shafts and the pin described above are inserted, and a pin insertion hole having a gap between the pin and the pin to allow eccentric movement of the planetary disk and the input shaft are provided. Thirdly, a casing for rotatably supporting the first input shaft and the output shaft with their shaft centers aligned with each other by a speed reducer having a pressing means for pressing the planetary disk toward the output shaft side, A second input shaft, which has a shaft center aligned between the first input shaft and the output shaft, is connected to the first input shaft in a rotational direction, and is rotatable with respect to the output shaft; First and second planetary disks eccentrically supported by first and second input shafts and rotatably supported, and wavy first and second epitrochoid curves formed on the outer circumferences of the first and second planetary disks. Surface and the first and second epitrochoidal curved surfaces, and the center of the axes of the first and second input shafts. It is sandwiched between the wavy first and second hypotrochoid curved surfaces provided in the casing as a core, the first and second epitrochoid curved surfaces, and the first and second hypotrochoid curved surfaces, and More than the number of waves on the first and second epitrochoid curved surfaces, and less than the number of waves on the first and second hypotrochoid curved surfaces, the first and second input shafts, and the first and second input shafts. A plurality of pins projecting from the output shaft in parallel with the output shaft, and a gap that allows the eccentric movement of the first and second planetary disks to be inserted between the pins and the pins are inserted. The first and second planetary discs have the first and second pin insertion holes formed in the first and second planetary discs, respectively, and the first and second planetary discs are provided with respect to the axes of the first and second input shafts. Fourth, by using the eccentric reducer on both sides, make the axes of the first input shaft and the output shaft coincide with each other. A casing rotatably supported and the first input shaft and the output shaft are aligned with each other so that one end is axially movable relative to the first input shaft and the other end is connected in the rotational direction. A second input shaft that is rotatably supported by the output shaft; and an elastic body that is provided between the first and second input shafts and that biases the first and second input shafts away from each other. First and second planetary disks eccentrically supported by the first and second input shafts and rotatably supported, and having an outer diameter on the input shaft side larger than an outer diameter on the output shaft side; The wavy first and second epitrochoidal curved surfaces formed on the outer periphery of the second planetary disk are opposed to the first and second epitrochoidal curved surfaces, and the axes of the first and second input shafts are arranged. First and first inner diameters, which are provided in the casing as a center and whose inner diameter on the input shaft side is larger than the inner diameter on the output shaft side. The corrugated first and second hypotrochoidal curved surfaces formed in the hole, and the first and second epitrochoidal curved surfaces and the first and second hypotrochoidal curved surfaces are sandwiched between the first and second hypotrochoidal curved surfaces. 2 The number of waves on the epitrochoid curved surface is larger than the number of waves on the first and second hypotrochoid curved surfaces, and the first and second balls are smaller than the number of waves on the hypotrochoid curved surface, and the first and second input shafts and the output shaft are And a plurality of pins projecting from the output shaft in parallel with each other and a gap that allows the eccentric movement of the first and second planetary disks to be formed between the pins into which the pins are inserted and the first and second pins. 2 the first and second pin insertion holes formed in the planetary disk, and pressing means for pressing the first and second planetary disks toward the output shaft side via the first input shaft. , The first and second planetary disks are eccentric to both sides of the axis of the first and second input shafts. The speed machine, has solved the above problems.

[0009]

[Action]

 In the first speed reducer, if the input shaft is rotated counterclockwise, the planetary disk is revolved to the left while drawing a circle whose radius is the eccentric distance. Since the planetary disk engages with the fixed hypotrochoidal curved surface via the epitrochoidal curved surface and the ball, it can revolve to the left and at the same time rotate to the right slower than the input shaft. The ball is sandwiched by the epitrochoid curved surface and the hypotrochoid curved surface from both sides, and receives the tangential force of the planetary disk from the epitrochoid curved surface and rolls on both curved surfaces while rotating counterclockwise.

Rotational torque due to the rotation of the planetary disk is transmitted to the output shaft by the pin and the pin insertion hole, and the output shaft is rotated in the same direction as the rotation direction of the planetary disk. At this time, the planetary disc revolves around the output shaft that cannot revolve, but the gap formed between the pin and the pin insertion hole allows the revolution about the output shaft.

In the second speed reducer, the planetary disk also revolves while drawing a circle having a radius of the eccentric distance on the input shaft, and also rotates slower than the input shaft. Rotational torque due to rotation is transmitted to the output shaft by the pin and the pin insertion hole. The pressing means presses the input shaft toward the output shaft to bias the epitrochoid curve surface on the planetary disk toward the hypotrochoid curve surface. The ball is sandwiched between the curved surfaces, and the backlash between the curved surface and the ball is reduced.

In the third speed reducer, the first and second planetary disks also revolve around the first and second input shafts while drawing a circle whose radius is the eccentric distance and are slower than the first and second input shafts. Rotate. Rotational torque due to rotation is transmitted to the output shaft by the pin and the first and second pin insertion holes. Also in this case, the first and second balls are sandwiched from both sides by the first and second epitrochoid curved surfaces and the first and second hypotrochoid curved surfaces, and the first and second epitrochoid curved surfaces are separated from each other. It rolls on both curved surfaces under the tangential force of the first and second planetary disks. Since the first and second planetary disks are eccentric on both sides of the axes of the first and second input shafts, the weight balance with respect to the first and second input shafts is maintained, and the first and second input shafts are smoothly moved. Rotate.

In the fourth speed reducer, the first and second planetary disks also revolve around the first and second input shafts while drawing a circle whose radius is the eccentric distance and are slower than the first and second input shafts. Rotate. Rotational torque due to rotation is transmitted to the output shaft by the pin and the first and second pin insertion holes. The pressing means presses the first input shaft toward the output shaft to urge the first epitrochoid curved surface on the first planetary disk toward the first hypotrochoid curved surface. The first ball is sandwiched between the curved surfaces to reduce backlash between the curved surface and the ball. When the first input shaft is pressed, the pressing means also presses the second input shaft to the output shaft side through the elastic body, and the second epitrochoid curved surface on the second planetary disk is also the second hypotrochoid. It is biased toward the curved surface. The second ball is sandwiched between the curved surfaces, and the backlash between the curved surface and the ball is reduced.

[0014]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS. The speed reducer 50 (see FIG. 1) mainly includes a casing 51, an input shaft 52, an output shaft 53, a planetary disk 54, a plurality of balls 55, an epitrochoid curved surface 56, and a hypotrochoid curved surface. 57 and a tightening nut (pressing means) 58.

Legs 62 are attached to the casing 51 with bolts 61. The casing 51 rotatably supports the input shaft 52 by a well-known angular bearing 63, and rotatably supports the output shaft 53 by a ball bearing 64. An oil seal 65 is provided between the casing 51 and the output shaft 53. The angular bearing 63 is provided between the casing 51 and the input shaft 52 in a direction in which the inner ring 67 is biased toward the output shaft 53 when the outer ring 66 is pressed. A known taper roller bearing (not shown) may be used instead of the angular bearing. The tip ends of the input shaft 52 and the output shaft 53 are connected to each other by a ball bearing 68 so as to abut each other with a space therebetween. The axis C1 of the input shaft 52 and the axis C2 of the output shaft 53 coincide with each other.

A cam 71 having an eccentric distance f is formed in an intermediate portion of the input shaft 52. Further, a balancer 72 for taking a weight balance of the cam 71, a planetary disk 54 described later, and the like is formed in an intermediate portion of the input shaft 52.

A ring-shaped planetary disk 54 is rotatably attached to the cam 71 by a known angular bearing 73. Therefore, the axis C3 of the cam 71 is also the axis of the planetary disk 54. The angular bearing 73 is provided between the cam 71 and the planetary disk 54 in such a direction that the outer ring 75 receives the pressing force when the inner ring 74 is pressed. A tapered roller bearing (not shown) may be used instead of the angular bearing.

The outer circumference of the planetary disk 54 (see FIGS. 1 and 2) has a taper 76 (see FIG. 1) in which the outer diameter D1 on the input shaft 52 side (see FIG. 2) is larger than the outer diameter D2 on the output shaft 53 side. (See). A wavy epitrochoidal curved surface 56 centered on the axis C3 of the planetary disk 54 is formed on the taper 76. The number of waves 77 is eighteen. Further, on the side surface of the planetary disk 54 on the output shaft 53 side, nine pins 79 are erected at equal intervals on a circle 78 (see FIG. 2) centered on the axis C3 of the planetary disk 54. There is. A ring-shaped roller 80 is rotatably attached to the tip of the pin 79.

A ring-shaped fixed ring plate 81 is fixed to the inner surface of the casing 51 (see FIG. 1) by bolts 82. The fixed ring plate 81 is provided at a position facing the outer circumference of the planetary disk 54. The inner periphery of the fixed ring plate 81 (see FIG. 3) has a tapered hole (hole having a larger inner diameter D3 on the input shaft 52 side than the inner diameter D4 on the output shaft 53 side and centered on the axial center C 1 of the input shaft 52). ) 83 (see FIG. 1). As shown in FIG. 3, a corrugated hypotrochoid curved surface 57 is formed in the tapered hole 83. The number of waves 84 is twenty.

Nineteen balls 55 are held between the epitrochoid curved surface 56 and the hypotrochoid curved surface 57. The ball 55 is held by a retainer 85 shown in FIGS. 5 and 6 so as not to fall off. The retainer 85 has 19 holes 86 for holding the balls 55. The heights H1 and H2 (see FIGS. 2 and 3) of the waves 77 and 84 on the epitrochoid curved surface 56 and the hypotrochoid curved surface 57 are the same. The radius of the ball 55 is set larger than the heights H1 and H2 of the waves 77 and 84.

A flange 87 is formed on the output shaft 53 (see FIG. 1) around the axis C2 of the output shaft 53. The collar 87 is supported on the casing 51 by a ball bearing 88. As shown in FIG. 4, a pin insertion hole 89 into which the pin 79 on the planetary disc 54 is inserted is formed on the surface of the collar 87 facing the planetary disc 54. The pin insertion holes 89 are arranged at equal intervals on a circle centered on the axis C2 of the output shaft 53. A gap S (= 2f 2) that is twice the eccentric distance f of the cam 71 is formed between the pin insertion hole 89 and the roller 80.

It should be noted that the pin 79 and the pin insertion hole 89 may be reversed in arrangement relationship, and the pin 79 may be provided so as to project from the flange 87 and the pin insertion hole 89 may be formed in the planetary disk 54. In the scope of claims for utility model registration, "gap" includes not only the gap between the pin and the pin insertion hole but also the gap between the roller and the pin insertion hole when the roller is mounted on the pin. It is a waste.

A ring-shaped tightening nut 58 is screwed onto the input shaft 52 side of the casing 51 (see FIG. 1). The tightening nut 58 is in contact with the outer ring 66 of the angular bearing 63.

Next, the operation will be described. When the casing 51 is fixed and the input shaft 52 is rotated counterclockwise, the planetary disk 54 revolves leftward from the state of FIG. 7 to the state of FIG. 8 while drawing a circle having a radius of the eccentric distance f. Since the planetary disk 54 is engaged with the fixed hypotrochoidal curved surface 57 via the epitrochoidal curved surface 56 and the ball 55, the planetary disk 54 revolves to the left and simultaneously rotates to the right slower than the input shaft 52. During this time, the ball 55 rotates counterclockwise while being sandwiched between the epitrochoid curved surface 56 and the hypotrochoid curved surface 57.

The ball 55 receives the tangential force of the planetary disk 54 from the epitrochoidal curved surface 56 and rolls. The rotational force of the planetary disk 54 due to its rotation is transmitted to the output shaft 53 by the pin 79 and the pin insertion hole 89, and the output shaft 53 is rotated in the same direction as the rotation direction of the planetary disk 54. At this time, the planetary disk 54 revolves around the output shaft 53, which cannot revolve, but the gap S formed between the roller 80 and the pin insertion hole 89 allows the revolution about the output shaft 53. To be done.

FIG. 8 shows that when the input shaft 52 is rotated counterclockwise about 180 degrees from the state of FIG. 7 (it can be judged from the fact that the shaft center C3 of the cam 71 integrated with the input shaft 52 is rotated about 180 degrees. ), The epitrochoidal curved surface 56, the ball 55, and the hypotrochoidal curved surface 57. In the figure, CL1 is the reference line of the fixed hypotrochoid curved surface 57, CL2 is the reference line of the ball 55, CL3 is the reference line of the planetary disk 54 and epitrochoid curved surface 56, and CL4 is the output shaft 53. 7 and 8 are compared, it can be seen that the output shaft 53 rotates slower than the input shaft 52.

When the tightening nut 58 is tightened, the tightening force is applied to the planetary disk 54 via the outer ring 66 of the angular bearing 63, the inner ring 67, the input shaft 52, the inner ring 74 of the angular bearing 73, and the outer ring 75. , The epitrochoidal curved surface 56 presses the ball 55 against the hypotrochoidal curved surface 57. As a result, backlash between the ball 55 and the curved surfaces 56 and 57 between the balls 55 and the bearings 63 and 73 is reduced.

The reduction ratio of the speed reducer 50 in the embodiment is that the number of waves 77 on the epitrochoidal curved surface 56 is 18, the number of balls 55 is 19, and the number of waves 84 on the hypotrochoidal curved surface 57 is 20. (2/18) ≈0.11.

Next, a speed reducer of another embodiment will be described with reference to FIG. The speed reducer 150 has a structure similar to that of the speed reducer 50 shown in FIG. 1, except that another second planetary disk 254 having substantially the same shape is provided on the right side of the planetary disk 54 of FIG. There is. Therefore, the first and second epitrochoid curved surfaces 156 and 256, the first and second balls 155 and 255, the first and second hypotrochoid curved surfaces 157 and 257, and the first and second angular bearings 173 and 273 are Since the epitrochoidal curved surface 56, the ball 55, the hypotrochoidal curved surface 57, and the angular bearing 73 in FIG. 1 have the same shapes, the description of these structures will be omitted. In addition, parts having the same structure as in FIG. 1 are shown by adding 1 to the head of the reference numerals in FIG. 1, and the description of the structure will be omitted.

The two planetary disks 154 and 254 are provided by first and second angular bearings 173 and 273, which are known to the first and second cams 171 and 271, on the first and second input shafts 152 and 252, respectively. It is rotatably installed. The first cam 171 and the first planetary disk 154, and the second cam 271 and the second planetary disk 254 are provided on both sides of the first and second input shafts 152 and 252 about the axis C1. The eccentric distance f of the axis C4 of the second cam 271 with respect to the axis C1 of the first and second input shafts 152 and 252 is the same as the eccentric distance f of the first cam 171.

Further, the first epitrochoid curved surface 156 and the first hypotrochoid curved surface 157, and the second epitrochoid curved surface 256 and the second hypotrochoid curved surface 257 are displaced from each other by a half pitch. That is, paying attention to the first and second balls 155 and 255 in the upper part of FIG. 9, the first ball 155 is formed by the wave troughs of the first epitrochoid curved surface 156 and the wave troughs of the first hypotrochoid curved surface 157. When sandwiched, the second ball 255 is sandwiched between the apex of the wave of the second epitrochoid curved surface 256 and the apex of the wave of the second hypotrochoid curved surface 257.

The first and second input shafts 152 and 252 are axially movable by a spline mechanism 293 and are connected in a rotational direction. The spline mechanism 293 includes a protrusion 291 formed in the axial direction of the first input shaft 152 and a groove 292 formed in the axial direction of the second input shaft 252 and engaged with the protrusion 291. Between the first input shaft 152 and the second input shaft 252, there is provided a ring-shaped coned spring (elastic body) 294 for urging the shafts 152 and 252 in a direction to separate them from each other. The end of the second input shaft 252 is rotatably supported by the output shaft 153 by a ball bearing 168.

The first and second planetary disks 154 and 254 are provided with first and second pin insertion holes 189 and 289 through which a pin 179 protruding from the flange 187 of the output shaft 153 passes. A gap equal to twice the eccentric distance f of the first and second cams 171 and 271 is formed between the pin 179 and the pin insertion holes 189 and 289.

Similarly to the speed reducer 50 shown in FIG. 1, when the input shaft 152 is rotated, the speed reducer 150 causes the first and second planetary disks 154 and 254 to move above the first and second input shafts 152 and 252. Then, it revolves while drawing a circle having a radius of the eccentric distance f and rotates about the axis slower than the first and second input shafts 152 and 252. Rotation torque caused by rotation of the first and second planetary disks 154 and 254 is transmitted to the output shaft 153 by the first and second pin insertion holes 189 and 289 and the pin 179.

The first and second balls 155, 255 are sandwiched from both sides by the first and second epitrochoid curved surfaces 156, 256 and the first and second hypotrochoid curved surfaces 157, 257, respectively, and The first and second epitrochoid curved surfaces 156 and 256 receive the tangential force of the first and second planetary disks 154 and 254 to roll on both curved surfaces 156, 256, 157 and 257 while rotating counterclockwise. Since the first and second planetary disks 154 and 254 are eccentric on both sides of the axis C1 of the first and second input shafts 152 and 252, the weight balance with respect to the first and second input shafts 152 and 252 is balanced. Therefore, the first and second input shafts 152 and 252 rotate smoothly.

When the tightening nut 158 is tightened, the tightening force passes through the outer ring 166 of the angular bearing 163, the inner ring 167, the first input shaft 152, the inner ring 174 of the first angular bearing 173, and the outer ring 175. In addition to the planetary disc 154, the first epitrochoidal curved surface 156 presses the first ball 155 against the first hypotrochoidal curved surface 157.

Further, the tightening force is applied to the second planetary disk 254 via the second input shaft 252, the belleville spring 284, the inner ring 274 and the outer ring 275 of the second angular bearing 273, and the second epitrochoid curved surface 256 is The two balls 255 are pressed against the second hypotrochoid curved surface 257. As a result, the “rattle” of each angular bearing 163, 173, 273 itself, the first and second epitrochoidal curved surfaces 156, 256, the first and second balls 155, 255, and the first and second The backlash between the hypotrochoid curved surfaces 157 and 257 is removed.

The epitrochoid curved surfaces 56, 156, 256 and the hypotrochoid curved surfaces 57, 157, 257 described above are the tapered surfaces 76, 176, 276 of the planetary disks 54, 154, 254, the tapered holes 83, 183 and 293 are formed in a tapered shape, but they are formed in a straight surface parallel to the input / output shafts 52, 152, 252, 53, 153 and a straight hole (neither of which is shown) to form a straight shape. May be.

The epitrochoidal curved surface and the hypotrochoidal curved surface are the planetary circles like the epitrochoidal curved surfaces 356, 456, 556 and the hypotrochoidal curved surfaces 357, 457, 557 shown in FIGS. 10 and 11. Among the angular bearings in which the plates 354, 454, 554 and the fixed ring plates 381, 481, 581 have a known cross-sectional shape in the thickness direction, planetary disks 354, 454, 5 having the same shape as the cross-sectional shape in the thickness direction of the outer ring. It may be formed in the outer periphery of 54 and the holes 390, 490, 590 of the fixed ring plates 381, 481, 581. In this case, the outer diameter D5 of the planetary disks 354, 454, 554 on the input shaft side is also set larger than the outer diameter D6 of the output shaft side. The inner diameter D7 of the holes 390, 490, 590 on the input shaft side is also set to be larger than the inner diameter D8 of the output shaft side.

Further, the epitrochoidal curve surface has the planetary disk 654, 754, 854 on the outer periphery of the planetary disk 654, 754, 854, as shown by the epitrochoidal curve surface 656, 756, 856 shown in FIGS. May be formed on the surfaces 695, 795, 895 having a V-shaped cross section in the thickness direction. In this case, when the speed reducer is assembled, the balls 655, 755, 855 are well settled, and the speed reducer can be assembled quickly and easily.

In the description of the operation of the speed reducers 50 and 150, the case where the casings 51 and 151 are fixed and the input shafts 52 and 152 are rotated has been described. However, the shape of the casings 51 and 151 can be hung on a belt. Even if the cylindrical casing is rotated by a driving device (not shown) with the input shafts 52 and 152 fixed, the rotational torque can be obtained from the output shafts 53 and 153.

[0042]

[Effect of device]

 In the speed reducer according to any one of claims 1 to 4, the balls are arranged on the outer circumference of the planetary disc, and the epitrochoidal curved face receives a force in the tangential direction of the planetary disc to form both epitrochoidal curved faces and hypotrochoidal curved faces. As it rolls on the top, the rotational torque loss is smaller than that of the conventional reducer, the trill transmission efficiency can be improved, and the contact area between the ball and both curved surfaces is wider than before. The effect of reducing wear on the ball and both curved surfaces is achieved. In the speed reducer according to claim 2 and claim 4, the ball is pressed between the tapered epitrochoid curved surface and the hypotrochoid curved surface by the pressing means. It is possible to reduce the backlash between them and improve the accuracy of the reduction gear ratio. Since the speed reducer of claim 3 and claim 4 has two planetary disks, the weight balance is good, the input and output shafts can be smoothly rotated, and the rotational torque is transmitted. Since the particles are dispersed in one planetary disk, wear on the ball, epitrochoid curve surface, and hypotrochoid curve surface can be reduced. When the epitrochoid curved surface is formed on the V-shaped surface as in claim 5, the balls are well settled when the speed reducer is assembled, and the speed reducer can be assembled quickly and easily. it can.

[Brief description of drawings]

FIG. 1 is a front view of a speed reducer according to an embodiment of the present invention.
It is sectional drawing along the output shaft.

FIG. 2 is a diagram of the planetary disk viewed from the right side in FIG.

FIG. 3 is a view of a fixed ring plate viewed from the left side in FIG.

FIG. 4 is a diagram showing an engaged state of a pin and a pin insertion hole.

FIG. 5 is a front view of the retainer.

FIG. 6 is a right side view of the retainer.

FIG. 7 is a diagram of the contact state between the epitrochoid curved surface, the ball, and the hypotrochoid curved surface in FIG. 1, as viewed from the right side.

8 is a diagram showing a state of contact between the epitrochoid curved surface, the ball and the hypotrochoid curved surface when the input shaft is rotated about 180 degrees to the left from the state of FIG. 7.

FIG. 9 is a front view of a speed reducer of another embodiment, which is a view corresponding to FIG. 1.

FIG. 10 is a front view of a planetary disk and a fixed ring plate of another embodiment, and is a cross-sectional view taken along the axis.

FIG. 11 is a front view of a planetary disk and a fixed ring plate of another embodiment, and is a cross-sectional view taken along the axis.

FIG. 12 is a front view of a planetary disk and a fixed ring plate of another embodiment, and is a cross-sectional view taken along the axis.

FIG. 13 is a front view of a planetary disk and a fixed ring plate of another embodiment, which is a cross-sectional view taken along the axis.

FIG. 14 is a front view of a conventional speed reducer, which is a cross-sectional view taken along an input / output shaft.

FIG. 15 is an exploded perspective view of the speed reducer of FIG.

[Explanation of symbols]

S Gap D1, D5 Input shaft side outer diameter D2, D6 Output shaft side outer diameter D3, D7 Input shaft side inner diameter D4, D8 Output shaft side inner diameter 50,150 Reducer 51,151 Casing 52,152,252 Input shaft 53,153 Output shaft 54,154,254,354,454,554,65
4,754,854 Planetary disk 55,155,255,655,755,855 Ball 56,156,256,356,456,556,65
6,756,856 Epitrochoid curve surface 57,157,257,357,457,557 Hypotrochoid curve surface 58,158 Clamping nut (pressing means) 76,176,276 Taper 77 Epitrochoid curve surface wave 79,179 Pin 83,183,293 Tapered hole (hole) 84 Wave of hypotrochoid curved surface 89,189,289 Pin insertion hole 294 Belleville spring (elastic body) 695,795,895 Surface with V-shaped section 390,490,590 hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Creator Takahiro Nishikawa 4-17 96 Tsurumi, Tsurumi-ku, Osaka-shi, Osaka Inside Tsubakimoto Chain Co., Ltd.

Claims (5)

[Scope of utility model registration request] 1. A casing for rotatably supporting an input shaft and an output shaft so as to abut against each other with a gap, and a planetary disk eccentrically supported by the input shaft so as to be rotatable.
A wavy epitrochoidal curved surface formed on the outer periphery of the planetary disk, and a wavy hypotrochoidal curved surface that is provided in the casing so as to face the epitrochoidal curved surface and center around the axis of the input shaft. A ball sandwiched between the epitrochoid curved surface and the hypotrochoid curved surface and less than the number of waves on the epitrochoid curved surface and less than the number of waves on the hypotrochoid curved surface, the planetary disk and the output shaft. A plurality of pins parallel to the input and output shafts, and a pin insertion hole having a gap for allowing the eccentric movement of the planetary disc to be inserted between the pins and the pins. The characteristic is a speed reducer. 2. A casing that rotatably supports an input shaft and an output shaft so as to abut against each other with a gap, and an outer diameter on the input shaft side that is eccentrically and rotatably supported by the input shaft. A planetary disk larger than the outer diameter on the shaft side, a wavy epitrochoidal curved surface formed on the outer periphery of the planetary disk, the epitrochoidal curved surface facing the epicenter, and centering around the axis of the input shaft. A wavy hypotrochoidal curved surface formed in a hole having an inner diameter on the input shaft side larger than the inner diameter on the output shaft side, and sandwiched between the epitrochoidal curved surface and the hypotrochoidal curved surface, and A ball that is more than the number of waves on the epitrochoidal curved surface and less than the number of waves on the hypotrochoidal curved surface, is provided between the planetary disk and the output shaft, and is parallel to the input and output shafts. A pin insertion hole having a plurality of pins and a pin inserted between the pins and allowing the eccentric movement of the planetary disc between the pin and the pin, and the planetary disc is pressed toward the output shaft side via the input shaft. A speed reducer comprising a pressing means. 3. A casing for rotatably supporting the first input shaft and the output shaft with the shaft centers aligned with each other, and the casing having the shaft centers aligned between the first input shaft and the output shaft. A second input shaft which is connected to the first input shaft in the rotational direction and is rotatable with respect to the output shaft, and first and second planetary circles eccentrically supported by the first and second input shafts so as to be rotatable. A plate and the first,
The wavy first and second epitrochoidal curved surfaces formed on the outer periphery of the second planetary disk and the axis of the first and second input shafts facing the first and second epitrochoidal curved surfaces are formed. The first and second hypotrochoid curved surfaces having a wavy shape provided in the casing as a center, and sandwiched between the first and second epitrochoid curved surfaces and the first and second hypotrochoid curved surfaces and 1. First and second balls, which are larger than the number of waves on the first and second epitrochoid curved surfaces and smaller than the number of waves on the first and second hypotrochoid curved surfaces, and the first and second balls
A gap that allows eccentric movement of the first and second planetary disks between a plurality of pins protruding from the output shaft parallel to the input shaft and the output shaft, and the pins into which the pins are inserted. And the first and second pin insertion holes formed in the first and second planetary discs, and the first and second planetary discs of the first and second input shafts. A decelerator characterized by being eccentric on both sides of the axis. 4. A casing for rotatably supporting a first input shaft and an output shaft with their axes coincident with each other, and an axial center of said first input shaft and said output shaft with one end having said first axis. A second input shaft that is axially movable relative to the input shaft, is connected in the rotational direction, and has the other end rotatably supported by the output shaft, and is provided between the first and second input shafts. 1st and 2nd
An elastic body for urging the input shafts away from each other and an eccentric rotatably supported first and second input shafts, the outer diameter of the input shaft side being larger than the outer diameter of the output shaft side. 1,
A second planetary disc, wavy first and second epitrochoidal curved faces formed on the outer circumferences of the first and second planetary discs, and facing the first and second epitrochoidal curved faces and First and second corrugations formed in the first and second holes, which are provided in the casing about the axes of the first and second input shafts and whose inner diameter on the input shaft side is larger than the inner diameter on the output shaft side, It is sandwiched between a second hypotrochoid curved surface, the first and second epitrochoid curved surfaces, and the first and second hypotrochoid curved surfaces, and more than the number of waves of the first and second epitrochoid curved surfaces. The first and second balls, which are less than the number of waves on the first and second hypotrochoid curved surfaces, and the first and second balls.
A gap that allows eccentric movement of the first and second planetary discs between a plurality of pins protruding from the output shaft parallel to the input shaft and the output shaft and the pins into which the pins are inserted. Through the first and second pin insertion holes formed in the first and second planetary disks, and the first and second planetary disks through the first input shaft. And a pressing means for pressing to, wherein the first and second planetary disks are eccentric to both sides of the axis of the first and second input shafts. 5. The epitrochoid curved surface is formed on the outer peripheral surface of a planetary disk having an outer peripheral surface having a V-shaped cross section in the thickness direction in place of the planetary disk. The speed reducer according to Item 2 or 4.