US4775289A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Statically-balanced direct-drive robot arm
Assignee: University of Minnesota System
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Filing: 1987-09-25
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Granted: 1988-10-04
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Expires: 2007-09-25
Abstract
Abstract A robot (10) includes a statically-balanced direct-drive arm (14) having three degrees of freedom, all of which are independent articulated drive joints, the driving axes of two of which intersect at the center of gravity of the arm to eliminate gravity forces on the drive system without counterweights.
Inventors
- 👤 Homayoon Kazerooni
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:43
CPC Classifications
B; B23; B23Q; B23Q11/00; B23Q11/001; B23Q11/0017; B23Q11/0021; B25; B25J; B25J19/00; B25J19/0008; B25J9/00; B25J9/0009; B25J9/0012; B25J9/02; B25J9/04; B25J9/10; B25J9/106; B25J9/1065; Y; Y10; Y10S; Y10S414/00; Y10S414/13; Y10S700/00; Y10S700/90
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
89 words
A statically-balanced robot arm, which comprises: a four-bar linkage having base, input, connecting, and output links; first drive means mounted on the base link for effecting pivotal movement of the input link of said linkage; said linkage and said first drive means having a predetermined center of gravity; means for supporting said linkage for independent pivotal movement about generally vertical and horizontal axes, said axes intersecting at said center of gravity; and second drive means for effecting independent pivotal movement of said linkage about the vertical and horizontal axes.
Claim 2
Dependent Claim
89 words
A statically-balanced robot arm, which comprises: a four-bar linkage having base, input, connecting, and output links; first drive means mounted on the base link for effecting pivotal movement of the input link of said linkage; said linkage and said first drive means having a predetermined center of gravity; means for supporting said linkage for independent pivotal movement about generally vertical and horizontal axes, said axes intersecting at said center of gravity; and second drive means for effecting independent pivotal movement of said linkage about the vertical and horizontal axes.
Claim 3
Dependent Claim
47 words
The robot arm of claim 1, wherein said first drive means comprises an electric motor having a housing and a drive shaft, the housing being fixed to the base link and the drive shaft being connected in rotatable driving engagement to the input link of said linkage.
Claim 4
Dependent Claim
23 words
The robot arm of claim 1, wherein the base, connecting and output links of said linkage are at least partially of tubular construction.
Claim 5
Dependent Claim
13 words
The robot arm of claim 1, wherein said supporting means comprises a clevis.
Claim 6
Dependent Claim
76 words
The robot arm of claim 1, wherein said second drive means comprises separate electric motors each having a housing and a drive shaft, the housing of one motor being fixed to said supporting means with its drive shaft connected in rotatable driving engagement about the horizontal axis with the base link of said linkage, and the drive shaft of the other motor being connected in rotatable driving engagement about the vertical axis to said supporting means.
Claim 7
Dependent Claim
108 words
A statically-balanced robot arm, which comprises: a four-bar linkage having base, input, connecting, and output links; control drive means mounted on the base link for effecting pivotal movement of the output link of said linkage; said linkage and said control drive means having a predetermined center of gravity; means for supporting said linkage for independent pivotal movement about generally vertical and horizontal axes, said axes intersecting at the said center of gravity; first drive means mounted on said supporting means for effecting pivotal movement of said linkage about the said horizontal axis; and second drive means for effecting pivotal movement of said supporting means about the said vertical
Claim 8
Dependent Claim
108 words
A statically-balanced robot arm, which comprises: a four-bar linkage having base, input, connecting, and output links; control drive means mounted on the base link for effecting pivotal movement of the output link of said linkage; said linkage and said control drive means having a predetermined center of gravity; means for supporting said linkage for independent pivotal movement about generally vertical and horizontal axes, said axes intersecting at the said center of gravity; first drive means mounted on said supporting means for effecting pivotal movement of said linkage about the said horizontal axis; and second drive means for effecting pivotal movement of said supporting means about the said vertical
Claim 9
Dependent Claim
18 words
The robot arm of claim 6, wherein said horizontal axis lies generally in the plane of said linkage.
Claim 10
Dependent Claim
158 words
A statically-balanced robot arm, comprising: a four-bar linkage having base, input, connecting, and output links; a first drive motor having a housing and a drive shaft, the housing being mounted on the base link and the shaft being drivingly connected to the input link of said linkage; said linkage and said first drive motor having a predetermined center of gravity; means for supporting said linkage for independent pivotal movement about intersecting perpendicular axes, said axes intersecting at the said center of gravity; a second drive motor having a housing and a drive shaft, the housing being mounted on said supporting means and the shaft being connected directly to the base link of said linkage for selective rotatable movement about one of said axes; and a third drive motor having a housing and a rotatable drive shaft, the drive shaft being connected directly to said supporting means for selective pivotal movement about the other one of said perpendicular axes.
Claim 11
Dependent Claim
158 words
A statically-balanced robot arm, comprising: a four-bar linkage having base, input, connecting, and output links; a first drive motor having a housing and a drive shaft, the housing being mounted on the base link and the shaft being drivingly connected to the input link of said linkage; said linkage and said first drive motor having a predetermined center of gravity; means for supporting said linkage for independent pivotal movement about intersecting perpendicular axes, said axes intersecting at the said center of gravity; a second drive motor having a housing and a drive shaft, the housing being mounted on said supporting means and the shaft being connected directly to the base link of said linkage for selective rotatable movement about one of said axes; and a third drive motor having a housing and a rotatable drive shaft, the drive shaft being connected directly to said supporting means for selective pivotal movement about the other one of said perpendicular axes.
Claim 12
Dependent Claim
18 words
The robot arm of claim 8, wherein said horizontal axis lies generally in the plane of said linkage.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-10-04 | 1992-04-04 | 1992-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-10-04 | 1996-04-04 | 1996-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-10-04 | 2000-04-04 | 2000-10-04 | $7700.00 | Window Closed / Lapsed |