Industrial robot wrist unit

Details Industrial robot wrist unit Industrial robot wrist unit

1997-07-24

1999-07-20

Marmor, Charles A

Machine element or mechanism

Control lever and linkage systems

Multiple controlling elements for single controlled element

7449001, 74396, 901 26, B25J 1702, B25J 910

Patent

active

059243309

DESCRIPTION:

BRIEF SUMMARY
BACKGROUND OF THE INVENTION

The present invention relates to an industrial robot wrist unit, comprising a wrist housing, which is intended to be detachably fixed to a distal end of a robot arm and in which there is pivotally mounted a tilt housing, which in turn supports a rotatably mounted turntable on which there can be mounted an external tool, first and second secondary drive shafts being rotatably mounted in the wrist housing, the first and second secondary drive shafts each having an input end which supports a gear for engagement with a respective drive gear on a respective primary drive shaft in the robot arm, the drive gears being disposed coaxial to each other and axially spaced, and where the first secondary drive shaft via a respective first gearing can rotate the turntable about a first axis and the second secondary drive shaft can, via a respective second gearing, pivot the tilt housing about a second axis, which crosses the first axis.
In a previously known wrist unit of the above mentioned type, the wrist housing comprises two halves, where each half has a through-hole for a respective secondary drive shaft. When assembled, the center axes of the holes for the secondary drive shafts in the housing halves, and thereby the center axis of the gears thereon, are disposed on diametrically opposite sides of the central coaxial driving gears on the primary drive shafts in the robot arm with which they are in engagement. In other words a straight line extends through the center axes of the secondary gears and the coaxial drive gears. This has made it difficult to adjust the clearance between the drive gears and their respective gears on the secondary drive shafts.


SUMMARY OF THE INVENTION

A primary purpose of the present invention is to suggest a wrist unit in which the aforementioned gear clearance can be easily adjusted. This is achieved by a wrist unit of the general type in which the gears and the drive gears (as seen in an end view projection) are placed relative to each other so that an imaginary line, extending through the centers of the gears, is offset from the centerline through the gears and that the wrist housing is radially adjustably fixable on the end of the robot arm for adjusting the gear clearance between, on the one hand, the drive gears on the primary drive shafts and, on the other hand, the gears on the secondary drive shafts.


BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described in more detail below with reference to the accompanying drawing, in which:
FIG. 1 is a partially sectioned longitudinal view of a wrist unit in accordance with the invention, mounted on a distal end of a robot arm; and
FIG. 2 is an end view of the wrist unit shown in FIG. 1 as seen from the end of the robot arm.


DETAILED DESCRIPTION OF THE INVENTION

With reference to FIG. 1, there is shown a wrist generally designated 10, for an industrial robot in accordance with the invention. The wrist 10 comprises in principle, a distal, fork-shaped wrist housing 12 with two fork arms 14 and 16, defining between them a groove-shaped space, the side walls 18,20 and bottom wall 22 of which are indicated in FIG. 1.
The wrist housing 12 is intended to be mounted on the distal end of a robot arm 24 by means of screw fasteners (not shown). FIG. 2 shows, however, four through-holes 26 for the anchoring screws in an anchoring flange 28 of the housing 12.
In the wrist housing 12 there is a so-called tilt housing 30 pivotally mounted about a transverse axis A and which supports in a manner known per se a turntable 32, which is rotatably mounted about a longitudinally oriented axis B. On the turntable 32 there can be mounted a chosen tool (not shown), such as a welding unit, gripping means, a spray-painting nozzle or the like. The portion of the tilt housing 30 supporting the turntable 32 and its shaft 34 is thus pivotable about the axis A in the space between the fork arms 14,16 through an arc of less than 360.degree.. The axis A is oriented perpendicular to the rotational axis B of the turntable 32.
For

REFERENCES:
patent: 4690012 (1987-09-01), Dahlquist et al.
patent: 4807486 (1989-02-01), Akeel et al.
patent: 5119687 (1992-06-01), Naruoka et al.
patent: 5456132 (1995-10-01), Iwanaga et al.
patent: 5549016 (1996-08-01), Nakako et al.
patent: 5775171 (1998-07-01), Richter

Affiliated with

Also associated with

Rating

Industrial robot wrist unit does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Industrial robot wrist unit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Industrial robot wrist unit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1312659