JPH0245554Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to an eccentric motion type speed reduction device that decelerates and extracts the eccentric motion of a pinion.

BACKGROUND TECHNOLOGY For example, a drive device that drives an arm of a robot includes a servo motor and a reducer that decelerates the rotation of the servo motor. Since the angle, speed, etc. must be accurately controlled, and the drive must be stopped reliably, a detection means for detecting information regarding the rotation of an encoder, resolver, tachogenerator, etc. and a brake means are incorporated into the drive device. It is.

Conventionally, such braking means and detection means are coupled to the output shaft of a servo motor, and
They are stacked on one side of the servo motor in the axial direction.

Problems to be Solved by the Invention However, in such an eccentric motion type reduction gear, at least the servo motor, brake means, and detection means are stacked in the axial direction, so the overall axial length is The problem is that it is long.

Means for solving the problem This problem can be solved by connecting a brake means that applies braking force to one crank pin, and
This problem can be solved by connecting a detection means for detecting information regarding rotation to the other crank pin.

Operation When the pinion eccentrically revolves, the crank pin inserted into the pinion also rotates at the same rotation speed. If the case is fixed, the rotation of the pinion is decelerated and transmitted to the carrier, and if the carrier is fixed, the rotation is decelerated and transmitted to the case. At this time, information regarding the rotation of the crank pin is detected by the detection means. Further, when applying a braking force to this reduction gear, the brake means is actuated to apply a braking force to the crank pin, thereby regulating rotation of the pinion. Here, since the detection means and the brake means are arranged radially outward, they can overlap each other, thereby making it possible to shorten the axial length of the reduction gear.

Embodiment Hereinafter, an embodiment of this invention will be described based on the drawings.

In FIGS. 1, 2, and 3, a pair of pinions 3 are housed in a cylindrical case 1 in which a large number of pin teeth 2 are formed on the inner periphery, and each pinion 3 has two pin teeth 2.
External teeth 6 are formed in which all the teeth mesh with each other and the number of teeth is slightly smaller than that of the pin teeth 2. The crank input shaft 7 is inserted into a shaft hole 8 formed in the center of each pinion 3, and a bearing 12 is interposed between the eccentric cam 10 and the shaft hole 8.
21 is a carrier, and a fitting shaft 24 of this carrier 21 is loosely fitted into a fitting hole 22 formed at the outer end of the pinion 3 in the radial direction. This fitting shaft 24
A left cover 25 is attached to the left cover 25 which holds the pinion 3 together with the carrier 21 from both sides by pins 26 and bolts 27. 28 is bolt 2
9 is the right cover attached to the carrier 21. The crank input shaft 7 bears a bearing 3.
It is rotatably supported by the left cover 25 and carrier 21 via 1. 33, 34 are bearings 35, 3
a pair of crank pins rotatably supported by the left cover 25 and carrier 21 via 7;
Eccentric cams 41 and 42 of each crank pin 33 and 34
are formed at the radially outer end of the pinion 3 and are connected to each other.
The eccentric cams 41 and 42 are inserted into pin holes 43 and 44 separated by 180 degrees, and bearings 45 and 46 are interposed between the pin holes 43 and 44 and the eccentric cams 41 and 42, respectively. 51 is a rotary encoder as a detection means connected to the other crank pin 33, and this rotary encoder 51 has a disc slit 52 fixed to the right end of the crank pin 33. 53 is a fixed slit fixed to the carrier 21, and this fixed slit 53 and the disk slit 52
is arranged between a light receiving element 54 attached to the carrier 21 and a light emitting diode 55 fixed to the right cover 28. Reference numeral 71 denotes a negative brake as a braking means connected to one crank pin 34, and the negative brake 71 includes a brake plate 72 splined to the right end of the crank pin 34, and a movable brake plate 72 disposed on both sides of the brake plate 72. It has possible brake plates 73, 74. A plurality of bolts 75 are provided between the brake plate 73 and the carrier 21.
A fixed disc 76 is interposed, and a brake plate 7
4 and the right cover 28 is a movable movable disc 77 into which the bolt 75 is inserted. A spring (not shown) is interposed between the movable disc 77 and the right cover 28, and the right cover 28 facing the movable disc 77
A coil 78 is housed inside. When rotational force is input to the crank input shaft 7, the coil 78 is energized and the brake plate 7
2, 73, 74, the fixed disc 76, and the movable disc 77 are separated from each other by electromagnetic force, and when no rotational force is input to the crank input shaft 7,
The coil 78 is de-energized, which causes
The spring presses the brake plates 72, 73, and 74 against the fixed disc 79 to apply a braking force to the crank pin 34.

Next, the operation of one embodiment of this invention will be explained.

Now, assume that rotational force is being input to the crank input shaft 7 from, for example, a servo motor (not shown). At this time, the eccentric cam 1 of the crank input shaft 7
0 rotation causes the pinion 3 to eccentrically revolve,
Due to this eccentric revolution movement of the pinion 3, the crank pins 33, 34 rotate at the same rotation speed as the crank input shaft 7. On the other hand, pinion 3 is crank pin 3
3 and 34 and whose external teeth 6 mesh with the pin teeth 2 of the case 1, the rotation of the crank input shaft 7 is transmitted to the case 1 at a reduced speed. At this time, the crank pin 33
Information regarding the rotation of the crank input shaft 7, that is, information regarding the rotation of the crank input shaft 7, is obtained by the light from the light emitting diode 55 passing through the disc and the fixed slits 52 and 53 and being received as a pulse by the light receiving element 54, which is transmitted to the rotary encoder. 51. Then, the detected pulses are transmitted as information such as position and angle to an information processing device (not shown), and this information processing device
The rotation speed, etc. are determined. Also, at this time, the rotary encoder 51 and the negative brake 7
1 is connected to the crank pins 33 and 34, respectively, so that they can overlap with the crank input shaft 7, and the axial length of the entire speed reduction device is shortened.
Next, when the input to the crank input shaft 7 ceases, the coil 78 is de-energized and the negative brake 71 applies braking force to the crank pin 34.

In addition, in this invention, the brake means may be capable of applying a braking force while the crank input shaft is rotating. Further, the detection means may be a resolver, a tachometer generator, or the like. Further, at least one pair of crank pins is sufficient, and there may be three or more crank pins. Further, a pre-stage reduction gear may be provided so that rotational input is directly transmitted to each crank pin. Also,
In this invention, the case may be fixed and the carrier may be rotated.

Effects of the invention As explained above, according to this invention, the axial length of the reduction gear device can be shortened.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing an embodiment of this invention, FIG. 2 is a sectional view taken along the - arrow in FIG. 1, and FIG. 3 is a sectional view taken in the - arrow direction in FIG. 1... Case, 2... Pin tooth, 3... Pinion, 7... Crank input shaft, 21... Carrier,
33, 34... Crank pin, 51... Detection means (rotary encoder), 71... Brake means (negative brake).

Claims (1)

[Scope of utility model registration request] A case with teeth formed on its inner periphery, a pinion that is housed in the case and meshes with the teeth with all its teeth and has slightly fewer teeth than the teeth and moves eccentrically, and a pair inserted into the radially outer end of the pinion. An eccentric movement type reduction gear device comprising a crank pin and a carrier rotatably supporting the crank pin, in which a brake means for applying a braking force is connected to one crank pin, and information regarding the rotation is connected to the other crank pin. What is claimed is: 1. An eccentric motion type deceleration device, characterized in that it is connected to a detection means for detecting.