JP-7857250-B2 - Gear system

JP7857250B2JP 7857250 B2JP7857250 B2JP 7857250B2JP-7857250-B2

Inventors

小田真暉
黒須優一

Assignees

住友重機械工業株式会社

Dates

Publication Date: 20260512
Application Date: 20230428

Claims (3)

A gear device comprising: an external gear; an internal gear; a first carrier positioned on one axial side of the external gear; a second carrier positioned on the other axial side of the external gear and connected to the first carrier; a knock pin for positioning the first and second carriers; and a connecting bolt for connecting the first and second carriers, The first carrier has a first knock pin hole into which the knock pin is inserted, The second carrier has a second knock pin hole into which the knock pin is inserted, The first knock pin hole has a first chamfered portion around the periphery of the opening, The second knock pin hole has a second chamfered portion on the periphery of the opening on the first carrier side. When the axial dimension of the first chamfered portion is H1 and the axial dimension of the second chamfered portion is H2, the sum of H1 and H2 is 0.1 mm or more and 0.9 mm or less. The first carrier includes a columnar shaft portion that extends axially at a position radially offset from the axis of the external gear and is connected to the second carrier by the connecting bolt. The gear apparatus is characterized in that the knock pin is positioned radially inward from the connecting bolt .
The gear device according to claim 1, characterized in that the axial dimension H1 is 0.45 mm or less, and the axial dimension H2 is 0.45 mm or less.
The gear apparatus according to claim 1 or 2, characterized in that the angle formed with the axial direction of the first and second chamfered portions is within the range of 30° to 60°.

Description

This invention relates to a gear mechanism. The applicant discloses an eccentric oscillating gear mechanism in Patent Document 1 (Figure 9). This gear mechanism comprises an output flange for extracting the rotational component of an external gear, and a counter flange positioned on the opposite side of the output flange, sandwiching the external gear. The counter flange is connected to the output flange via carrier pins and carrier bolts. Furthermore, knock pins are press-fitted into both flanges to maintain a precise relative position between the counter flange and the output flange. Japanese Patent Publication No. 2017-048889 This is a side cross-sectional view showing a gear device according to an embodiment.This is an enlarged view showing the area around the knock pin hole of the gear mechanism in Figure 1.This is a schematic diagram showing the relationship between the chamfer dimensions of the knock pin hole and the bending stress.This is another schematic diagram showing the relationship between the chamfer dimensions of the knock pin holes and the bending stress.This graph shows the relationship between the chamfer dimensions of the knock pin holes and durability. The present invention will be described below with reference to the drawings, based on preferred embodiments. In embodiments and modifications, the same or equivalent components and members will be denoted by the same reference numerals, and redundant explanations will be omitted as appropriate. In addition, the dimensions of the members in each drawing will be enlarged or reduced as appropriate to facilitate understanding. Furthermore, some members that are not important for explaining the embodiments will be omitted from the drawings. Furthermore, while terms including ordinal numbers such as "first" and "second" are used to describe various components, these terms are used solely to distinguish one component from others, and do not limit the components themselves. [Embodiment] The configuration of the gear device 100 according to an embodiment of the present invention will be described below with reference to the drawings. Figure 1 is a side cross-sectional view showing the gear device 100. The gear device 100 of this embodiment is a so-called distribution type eccentric oscillating reduction gear. This gear device 100 is configured to generate rotation of one of the internal gears and the external gears by oscillating the external gear that meshes with the internal gear, and to output the resulting rotation component from the output member to the driven device. The gear unit 100 mainly comprises an input gear 70, a crankshaft 12, an external gear 14, an internal gear 16, carriers 18 and 20, a casing 22, and main bearings 24 and 26. Hereinafter, the direction along the central axis La of the internal gear 16 will be referred to as the "axial direction," and the circumferential and radial directions of the circle centered on that central axis La will be referred to as the "circumferential direction" and "radial direction," respectively. Furthermore, for convenience, one side of the axial direction (right side in the diagram) will be referred to as the input side, and the other side (left side in the diagram) as the non-input side. (Input gear) Three input gears 70 are arranged around the central axis La of the internal gear 16. The three input gears 70 are positioned at equal intervals of 120°, offset from the central axis La. Figure 1 shows only one input gear 70. Three crankshafts 12 are provided, corresponding to the three input gears 70. The crankshafts 12 are inserted through the center of the input gears 70 and support the input gears 70. A pair of crankshaft bearings 34 are provided on both axial sides of the crankshaft 12. The crankshafts 12 are provided so as to be rotatable integrally with the input gears 70. The three input gears 70 mesh with the external teeth (not shown) of a rotating shaft (not shown) provided on the central axis La. Rotational power is transmitted to this rotating shaft from a drive device (not shown), and the rotation of this rotating shaft causes the input gears 70 to rotate integrally with the crankshafts 12. The drive device is, for example, a motor, gear motor, engine, etc. (Crank axle) The crankshaft 12 in this embodiment is an eccentric shaft having a plurality of eccentric portions 12a for oscillating the external gear 14. The axes of the eccentric portions 12a are eccentric with respect to the rotational centerline of the crankshaft 12. In this embodiment, two eccentric portions 12a are provided, and the eccentric phases of adjacent eccentric portions 12a are shifted by 180°. The crankshaft 12 is supported on its input side by the second carrier 20 via a crankshaft bearing 34, and on its non-input side by the first carrier 18 via a crankshaft bearing 34. The non-input side crankshaft bearing 34 is fitted and supported in the crankshaft hole 18h of the first carrier 18, and the input side cranksh