Generally, adjustment of gravity equilibrators to a new payload requires energy, e.g., to increase the preload of the balancing spring. A novel way of energy-free adjustment of gravity equilibrators is possible by introducing the concept of a storage spring. The storage spring supplies or stores the energy necessary to adjust the balancer spring of the gravity equilibrator. In essence, the storage spring mechanism maintains a constant potential energy within the spring mechanism; energy is exchanged between the storage and the balancer spring when needed. Various conceptual designs using both zero-free-length springs and regular extension springs are proposed. Two models were manufactured demonstrating the practical embodiments and functionality.

References

References
1.
Herder
,
J. L.
, 2001, “
Energy-free Systems; Theory, Conception and Design of Statically Balanced Spring Mechanisms
,” Ph.D. thesis, Delft University of Technology, The Netherlands. Available online at: http://repository.tudelft.nl/http://repository.tudelft.nl/
2.
Carwardine
,
G.
, 1934, “
Improvements in Elastic Equipoising Mechanisms
,” Patent No. GB404615.
3.
French
,
M.
, and
Widden
,
M.
, 2000, “
The Spring-and-Lever Balancing Mechanism, George Carwardine and the Anglepoise Lamp
,”
Proc. IMechE Part C: J. Mech. Eng. Sci.
,
214
(
3
), pp.
501
508
.
4.
Brown
,
T.
, and
DiGuilio
,
A. O.
, 1980, “
Support Apparatus
,”
U.S. Patent No.
4
,
208
,
028
.
5.
Gosselin
,
C. M.
, and
Wang
,
J.
, 2000, “
Static Balancing of Spatial Six-Degree-of-Freedom Parallel Mechanisms With Revolute Actuators
,”
J. Rob. Syst.
,
17
(
3
), pp.
159
170
.
6.
Gopalswamy
,
A.
,
Gupta
,
P.
, and
Vidyasagar
,
M.
, 1992, “
A New Parallelogram Linkage Configuration for Gravity Compensation Using Torsional Springs
,”
Proceedings of the 1992 IEEE International Conference on Robotics and Automation
,
Nice
,
France
, May, pp.
664
669
.
7.
van Dorsser
,
W. D.
,
Barents
,
R.
,
Wisse
,
B. M.
, and
Herder
,
J. L.
, 2007, “
Gravity-Balanced Arm Support With Energy-Free Adjustment
,”
ASME J. Med. Devices
,
1
(
2
), pp.
151
158
.
8.
Rahman
,
T.
,
Sample
,
W.
,
Seliktar
,
R.
,
Alexander
,
M.
, and
Scavina
,
M.
, 2000, “
A Body-Powered Functional Upper Limb Orthosis
,”
J. Rehabil. Res. Dev.
,
37
(
6
), pp.
675
680
.
9.
Lynen
,
W.
, 1904, “
Federwerk
,” Patent No.DE157513.
10.
Herder
,
J. L.
,
Cool
,
J. C.,
and
Plettenburg
,
D. H.
, 1998, “
Methods for Reducing Energy Dissipation in Cosmetic Gloves
,”
J. Rehabil. Res. Dev.
,
35
(
2
), pp.
201
209
.
11.
van Dorsser
,
W. D.
,
Barents
,
R.
,
Wisse
,
B. M.
, and
Herder
,
J. L.
, 2005, “
Balancing Device
,” Patent Nos. NL1029989C, WO2007035096, US2008210842.
12.
van Dorsser
,
W. D.
,
Barents
,
R.
,
Wisse
,
B. M.
,
Schenk
,
M.
, and
Herder
,
J. L.
, 2008, “
Energy-Free Adjustment of Gravity Equilibrators Using the Possibility of Adjusting the Spring Stiffness
,”
Proc. IMechE Part C: J. Mech. Eng. Sci.
,
222
(
9
), pp.
1839
1846
.
13.
Wisse
,
B. M.
,
van Dorsser
,
W. D.
,
Barents
,
R.
, and
Herder
,
J. L.
, 2007, “
Energy-Free Adjustment of Gravity Equilibrators Using the Virtual Spring Concept
,”
Proceedings of ICORR2007, 10th International Conference on Rehabilitation Robotics
,
Noordwijk
,
The Netherlands
, June 13–15, pp.
742
750
.
14.
LaCoste
,
L. J. B.
, 1934, “
A New Type Long Period Vertical Seismograph
,”
Physics
,
5
(
7
), p.
178
.
15.
Willmore
,
P. L.
, 1966, “
Long Period Vertical Seismograph
,” Patent No. US3292145.
16.
Soper
,
R.
,
Mook
,
D.
, and
Reinholtz
,
C.
, 1997, “
Vibration of Nearly Perfect Spring Equilibrators
,”
Proceedings of the 1997 ASME Design Engineering Technical Conference
, Paper No. DAC-3768.
17.
Gund
,
K.
, 1955, “
Kräfteausgleichsvorrichtung
,” Patent No. DE936966.
18.
Soethoudt
,
B.
, 1998, “
A New Ideal Spring Arrangement
,” Internal Report, Delft University of Technology, OCP-MMS, (in Dutch).
19.
te Riele
,
F. L. S.
, and
Herder
,
J. L.
, 2001, “
Perfect Static Balance With Normal Springs
,”
Proceedings of the 2001 ASME Design Engineering Technical Conferences
,
Pittsburg
,
PA
, Sept.
9
12
, Paper No. DETC2001/DAC21096.
20.
Carwardine
,
G.
, 1938, “
Improvements in and Relating to Elastic Force and Equipoising Mechanisms
,” Patent No. GB489547.
21.
Jackson
,
E. V.
, and
Matthew
,
M. P.
, 1965, “
Instrument Table
,” Patent No. US3179364.
22.
Kuntz
,
J. P.
, 1995, “
Rolling Link Mechanisms
,” Ph.D. thesis, Delft University of Technology, The Netherlands. Available online at: http://repository.tudelft.nl/http://repository.tudelft.nl/
23.
Carwardine
,
G.
, 1931, “
Improvements in Elastic Force Mechanisms
,” Patent No. GB377251.
24.
Barents
,
R.
, 2006, “
The Space Cabinet. The Theory and Design of Self-Adjusting Balancing Mechanisms With Application to a Vertically Displaceable Cabinet
,” M.Sc. thesis, Delft University of Technology, The Netherlands.
25.
Tidwell
,
P. H.
,
Bandukwala
,
N.
,
Dhande
,
S. G.
,
Reinholtz
,
C. F.
, and
Webb
,
G.
, 1994, “
Synthesis of Wrapping Cams
,”
ASME J. Mech. Des.
,
116
(
2
), pp.
634
638
.
You do not currently have access to this content.