I claim:
1. An electrical circuit assembly, comprising:
a node supplying a potential; and
an electrical circuit drawing, dependent upon the potential at said node, said node to a given potential when and for as long as said node is not drawn in any other way to a different potential.
2. The assembly according to claim 1, wherein said electrical circuit is a pull-up circuit drawing said node to a high voltage level when and for as long as said node is not drawn in another way to a lower voltage level.
3. The assembly according to claim 1, wherein said electrical circuit is a pull-down circuit drawing said node to a low voltage level when and for as long as said node is not drawn in another way to a higher voltage level.
4. The assembly according to claim 1, wherein said electrical circuit is part of an integrated circuit, and said node is connected to an input connection of the integrated circuit.
5. The assembly according to claim 1, including a further electrical circuit connected to said node, said further electrical circuit operating dependent upon the potential at said node.
6. The assembly according to claim 1, wherein said electrical circuit has a component connecting said node to said given potential to which said node is to be brought by said electrical circuit.
7. The assembly according to claim 6, wherein said electrical circuit has a second component connecting said node to said given potential to which said node is to be brought by said electrical circuit.
8. The assembly according to claim 7, including a switching element, and wherein:
said second component is connected through said switching element to said node;
said switching element is opened when the potential at said node is below a threshold value; and
said switching element is closed when the potential at said node is one of:
above said threshold value; and
above a second threshold value.
9. The assembly according to claim 8, including a comparator having an output providing an output signal controlling said switching element, said comparator comparing the potential at said node with said threshold voltage.
10. The assembly according to claim 6, wherein said component is a resistor.
11. The assembly according to claim 7, wherein said second component is a resistor.
12. The assembly according to claim 6, wherein said component is a current source.
13. The assembly according to claim 7, wherein said second component is a current source.
14. The assembly according to claim 6, wherein said component has a control input and, by driving said component through said control input, said component selects how strongly said node is drawn to said given potential.
15. The assembly according to claim 14, including a control device having an output providing an output signal, and wherein said component is a transistor having:
a drain connected to said node;
a source receiving a voltage corresponding approximately to said given potential to which said node is to be brought; and
a gate connected to said output of said control device.
16. The assembly according to claim 15, including a supply voltage having a first pole and a second pole, said supply voltage supplying power to said control device, and wherein:
said control device includes:
a second transistor having a source, and a drain;
a third transistor having a source, a drain, and a gate; and
a current source having a first pole and a second pole;
said second transistor, said third transistor, and said current source are connected in series;
said source of said second transistor is connected to said first pole of said supply voltage;
said drain of said second transistor is connected to said source of said third transistor;
said gate of said second transistor is connected to said node;
said drain of said third transistor is connected to said first pole of said current source, to said gate of said third transistor, and to said gate of said transistor;
said gate of said third transistor is connected to said first pole of said current source, to said drain of said third transistor, and to said gate of said transistor and;
said first pole of said current source is connected to said gate of said transistor;
said second pole of said current source is connected to said second pole of said supply voltage.
17. An electrical circuit assembly, comprising:
a node supplying a potential; and
an electrical circuit drawing, dependent upon the potential at said node, said node to a given potential when and for as long as said node is not drawn in any other way to a different potential, said electrical circuit having:
a first component connecting said node to said given potential to which said node is to be brought by said electrical circuit;
a second component connecting said node to said given potential to which said node is to be brought by said electrical circuit; and
a switching element connecting said second component to said node, said switching element:
being opened when the potential at said node is below a threshold value; and
being closed when the potential at said node is one of:
above said threshold value; and
above a second threshold value.
18. The assembly according to claim 17, including a comparator having an output providing an output signal controlling said switching element, said comparator comparing the potential at said node with said threshold voltage.
19. The assembly according to claim 17, wherein said first component is a resistor.
20. The assembly according to claim 17, wherein said second component is a resistor.
21. The assembly according to claim 17, wherein said first component is a current source.
22. The assembly according to claim 17, wherein said second component is a current source.
23. The assembly according to claim 16, wherein said first component has a control input and, by driving said component through said control input, said first component selects how strongly said node is drawn to said given potential.
24. An electrical circuit assembly, comprising:
a node supplying a potential;
an electrical circuit drawing, dependent upon the potential at said node, said node to a given potential when and for as long as said node is not drawn in any other way to a different potential, said electrical circuit having:
a control device having an output providing an output signal;
a transistor connecting said node to said given potential to which said node is to be brought by said electrical circuit, said transistor having:
a drain connected to said node;
a source receiving a voltage corresponding approximately to said given potential to which said node is to be brought; and
a gate connected to said output of said control device.
25. The assembly according to claim 24, including a supply voltage having a first pole and a second pole, said supply voltage supplying power to said control device, and wherein:
said control device includes:
a second transistor having a source, and a drain;
a third transistor having a source, a drain, and a gate; and
a current source having a first pole and a second pole;
said second transistor, said third transistor, and said current source are connected in series;
said source of said second transistor is connected to said first pole of said supply voltage;
said drain of said second transistor is connected to said source of said third transistor;
said gate of said second transistor is connected to said node;
said drain of said third transistor is connected to said first pole of said current source, to said gate of said third transistor, and to said gate of said transistor;
said gate of said third transistor is connected to said first pole of said current source, to said drain of said third transistor, and to said gate of said transistor;
said first pole of said current source is connected to said gate of said transistor; and
said second pole of said current source is connected to said second pole of said supply voltage.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A motor-less, leg-powered curved treadmill comprising:
a treadmill frame having peripheral left and right sides;
a concave row of upper support peripheral ball bearings located at each of the peripheral left and right sides of the treadmill frame; and
a set of respective front and rear pulley end rollers for rotation;
a closed loop treadmill belt, wherein said front and rear pulley end rollers support said closed loop treadmill belt;
wherein said closed loop treadmill belt comprises a plurality of parallel transverse slats oriented perpendicular to an axis of rotation of said belt and attached to each other in a resilient fashion; and
wherein each said transverse slat includes a plurality of fins connected to and extending outward from each said transverse slat and formed with a material with sufficient resiliency, strength and weight to lie on and conform to the respective concave rows of the upper support peripheral ball bearings.
2. The motor-less, leg-powered curved treadmill as in claim 1 wherein respective side covers enclose an underlying chassis.
3. The motor-less, leg-powered curved treadmill as in claim 1 wherein said motor-less, leg-powered curved treadmill is provided without a handle bar assembly.
4. The motor-less, leg-powered curved treadmill as in claim 1 wherein said motor-less, leg-powered curved treadmill is provided with a removable handle bar assembly, which when installed on said motor-less, leg-powered curved treadmill, said handle bar assembly help users who are balance-challenged to use said motor-less, leg-powered curved treadmill.
5. The motor-less, leg-powered curved treadmill as in claim 2 wherein said chassis includes at least one robust cross beam attaching respective outer frames and respective inner frames on each side to each other, thereby providing a rectangular chassis.
6. The motor-less, leg-powered curved treadmill as in claim 1 wherein said transverse slats are made of a material selected from the group consisting of rubber, plastic and wood.
7. The motor-less, leg-powered curved treadmill as in claim 1 wherein respective adjusters are provided on at least one set of said pulley end rollers to adjust the distance separating said pairs of front and rear pulley end rollers to ensure precise smooth movement of said belt over said pairs of front and rear pulley end rollers.
8. The motor-less, leg-powered curved treadmill as in claim 1 further comprising level adjusters extending down from said frame to adjust the tilt of said motor-less, leg-powered curved treadmill.
9. The motor-less, leg-powered curved treadmill as in claim 1, wherein each said row of peripheral ball bearings are spaced apart from each other on the respective left and right sides of said treadmill frame, wherein said fins of said transverse slats extend cantilevered outward into a vacant mid-section of said treadmill from each said transverse slat and wherein said resiliency enables said transverse slats to dip slightly under the weight of the user runner without any lower support below non-peripheral mid-sections of said transverse slats.