Gear device

• US 7,597,643 B2
• Filed: 06/30/2006
• Issued: 10/06/2009
• Est. Priority Date: 06/30/2006
• Status: Active Grant

• Current Assignee: I'M SPA
• Original Assignee: I'M SPA
• Inventors: Shimada, Toshiaki
• Primary Examiner(s): Wright; Dirk
• Application Number:
  US11/575,126
• Publication Number:
  US 20090054192A1
• Time in Patent Office: 1,194 Days
• Field of Search: 74/52, 74/893.4, 74/891.6
• US Class Current: 475/178
• CPC Class Codes: F16D 2121/26 for releasing a normally applied brake
• CPC Class Codes: F16D 2125/40 Screw-and-nut
• CPC Class Codes: F16D 2125/50 with parallel non-stationary axes, e.g. planetary gearing
• CPC Class Codes: F16D 65/18 adapted for drawing members together , e.g. for disc brakes
• CPC Class Codes: F16H 1/32 in which the central axis of the gearing lies inside the periphery of an orbital gear

Abstract

First input-side eccentric part 39a of an input shaft 39 is inserted into a central hole of an external gear 47. A crank pin 60 for controlling the motion of the external gear 47 has a first crank-side eccentric part 60d whose eccentricity is equal to that of the first input-side eccentric part 39a. The first crank-side eccentric part 60d is engaged with the external gear 47. The input shaft 39 has a second input-side eccentric part 39b whose eccentricity is larger than that of the first input-side eccentric part 39a. The second input-side eccentric part 39b is provided with a driving member 49 such that the driving member 49 is rotatable. The crank pin 60 has a second crank-side eccentric part 60c whose eccentricity is equal to that of the rear eccentric part 39b. The second crank-side eccentric part 60c is engaged with the driving plate 67.

Claims

1. An eccentrically-orbital gear device, comprising:

an internal gear;

an external gear placed inside the internal gear;

an input shaft having a first input-side eccentric part which is inserted in a central hole formed in the external gear such that the first input-side eccentric part is rotatable around its center line; and

a crankshaft rotatably supported by a device main body, the crankshaft having a first crank-side eccentric part which is engageable with the external gear with an eccentricity equal to that of the first input-side eccentric part, the external gear producing eccentrically-orbital motion while being meshed with the internal gear and being inhibited by the crankshaft from rotating, wherein

the input shaft has a second input-side eccentric part whose eccentricity is larger than that of the first input-side eccentric part,

the second input-side eccentric part is provided with a driving member for driving the crankshaft such that the driving member is rotatable around a center line of the second input-side eccentric part, and

the crankshaft has a second crank-side eccentric part which has an eccentricity equal to that of the second input-side eccentric part and which is engageable with the driving member.

2. The gear device of claim 1, wherein the crankshaft includes a plurality of crankshafts.

3. The gear device of claim 2, wherein the plurality of crankshafts are driven by a single driving member.

4. The gear device of claim 2, further comprising a linking member for linking the plurality of crankshafts.