1. A liquid level sensor component comprising:
(a) a first elongated, insulated substrate having an inner resistive elongated closed loop having first and second resistive elongated legs formed thereon along the length of said first elongated insulated substrate and positioned between first and second resistive elongated legs of an outer resistive elongated closed loop formed thereon along the length of said first elongated insulated substrate;
(b) a second elongated insulated substrate having an elongated strip of an electrically conductive material thereon positioned over the first and second resistive elongated legs of the inner resistive elongated closed loop but not over the first and second resistive elongated legs of the outer resistive elongated closed loop; and wherein
(c) said first and second insulated substrates are coupled together face to face by a coupling member in a manner providing separation of said first and second insulated substrates in the absence of hydrostatic pressure thereon, and for causing conductive bridging contact by said elongated strip of an electrically conductive material contacting the first and second resistive elongated legs of the inner resistive elongated loop, but not contacting the first and second resistive elongated second legs of the outer resistive elongated loop, in the presence of hydrostatic pressure thereon.
2. The sensor of claim 1 wherein lower terminal portions of the inner resistive elongated closed loop and lower terminal portions of the outer resistive elongated closed loop are positioned within a leading bottom portion of the liquid level sensor without being coupled to an electrical contact outside of the bottom portion of the liquid level sensor.
3. The sensor of claim 1 wherein said coupling member comprises a spacer layer having an elongated window therein positioned between said first and second insulated substrates.
4. The sensor of claim 1 wherein the inner and outer resistive elongated closed loops are printable resistive inks.
5. The sensor of claim 4 wherein lower terminal portions of the inner resistive elongated closed loop and lower terminal portions of the outer resistive elongated closed loop are positioned within a leading bottom portion of the liquid level sensor without being coupled to an electrical contact outside of the bottom portion of the liquid level sensor.
6. The sensor of claim 1 wherein the resistivity of the inner closed loop equals the resistivity of the outer closed loop.
7. The sensor of claim 6 wherein lower terminal portions of the inner resistive elongated closed loop and lower terminal portions of the outer resistive elongated closed loop are positioned within a leading bottom portion of the liquid level sensor without being coupled to an electrical contact outside of the bottom portion of the liquid level sensor.
8. The sensor of claim 6 wherein the inner and outer resistive elongated closed loops are printable resistive inks.
9. The sensor of claim 8 wherein said electrically conductive material is a printable resistive ink enabling printing of the same resistive ink upon the first and second insulated substrates, thereby to save manufacturing costs.
10. The sensor of claim 8 wherein lower terminal portions of the inner resistive elongated closed loop and lower terminal portions of the outer resistive elongated closed loop are positioned within a leading bottom portion of the liquid level sensor without being coupled to an electrical contact outside of the bottom portion of the liquid level sensor.
11. A liquid level sensor apparatus comprising:
(a) a first elongated, insulated substrate having an inner resistive elongated closed loop having first and second resistive elongated legs formed thereon along the length of said first elongated insulated substrate and positioned between first and second resistive elongated legs of an outer resistive elongated closed loop formed thereon along the length of said first elongated insulated substrate;
(b) a second elongated insulated substrate having an elongated strip of an electrically conductive material thereon positioned over the first and second resistive elongated legs of the inner resistive elongated closed loop but not over the first and second resistive legs of the outer resistive elongated closed loop; and wherein
(c) said first and second insulated substrates are coupled together face to face by a coupling member in a manner providing separation of said first and second insulated substrates in the absence of hydrostatic pressure thereon, and for causing electrically conductive bridging contact by said elongated strip of an electrically conductive material contacting the first and second resistive elongated legs of the inner resistive elongated loop, but not contacting the first and second resistive elongated legs of the outer resistive elongated loop, in the presence of hydrostatic pressure thereon;
(d) a Wheatstone bridge wherein
(d-1) upper terminal portions of the inner resistive elongated closed loop are positioned within a first lower leg of the Wheatstone bridge; and
(d-2) wherein upper terminal portions of the outer resistive elongated closed loop are positioned within a second lower leg of the Wheatstone bridge.
12. The sensor of claim 11 wherein lower terminal portions of the inner resistive elongated closed loop and lower terminal portions of the outer resistive elongated closed loop are positioned within a leading bottom portion of the liquid level sensor without being coupled to an electrical contact outside of the bottom portion of the liquid level sensor.
13. The sensor of claim 11 wherein said coupling member comprises a spacer layer having an elongated window therein positioned between said first and second insulated substrates.
14. The sensor of claim 11 wherein the inner and outer resistive elongated closed loops are printable resistive inks.
15. The sensor of claim 14 wherein lower terminal portions of the inner resistive elongated closed loop and lower terminal portions of the outer resistive elongated closed loop are positioned within a leading bottom portion of the liquid level sensor without being coupled to an electrical contact outside of the bottom portion of the liquid level sensor.
16. The sensor of claim 11 wherein the resistivity of the inner closed loop equals the resistivity of the outer closed loop.
17. The sensor of claim 16 wherein lower terminal portions of the inner resistive elongated closed loop and lower terminal portions of the outer resistive elongated closed loop are positioned within a leading bottom portion of the liquid level sensor without being coupled to an electrical contact outside of the bottom portion of the liquid level sensor.
18. The sensor of claim 16 wherein the inner and outer resistive elongated closed loops are printable resistive inks.
19. The sensor of claim 18 wherein said electrically conductive material is a printable resistive ink enabling simultaneous printing of the same resistive ink upon the first and second insulated substrates, thereby to save manufacturing costs.
20. The sensor of claim 18 wherein lower terminal portions of the inner resistive elongated closed loop and lower terminal portions of the outer resistive elongated closed loop are positioned within a leading bottom portion of the liquid level sensor without being coupled to an electrical contact outside of the bottom portion of the liquid level sensor.
21. A liquid level sensor apparatus comprising:
(a) a first elongated, insulated substrate having an inner resistive elongated closed loop having first and second resistive elongated legs formed thereon along the length of said first elongated insulated substrate and positioned between first and second resistive elongated legs of an outer resistive elongated closed loop formed thereon along the length of said first elongated insulated substrate;
(b) a second elongated insulated substrate having an elongated strip of an electrically conductive material thereon positioned over the first and second resistive elongated legs of the inner resistive elongated closed loop but not over the first and second resistive legs of the outer resistive elongated closed loop; and wherein
(c) said first and second insulated substrates are coupled together face to face by a coupling member in a manner providing separation of said first and second insulated substrates in the absence of hydrostatic pressure thereon, and for causing electrically conductive bridging contact by said elongated strip of an electrically conductive material contacting the first and second resistive elongated legs of the inner resistive elongated loop, but not contacting the first and second resistive elongated legs of the outer resistive elongated loop, in the presence of hydrostatic pressure thereon; and
(d) a comparator for comparing the resistance of the inner elongated closed loop with the resistance of the outer elongated closed loop that produces a difference signal indicative of the level of the liquid sensed by the sensor apparatus.
22. The liquid level sensor apparatus of claim 21 wherein said comparator is selected from the group consisting of a Wheatstone bridge, an operational amplifier, and a pair of voltage divider circuits which are coupled to two separate analog inputs of a microcontroller for comparison of output signals from the voltage divider circuits.
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 spindle motor comprising:
a lower thrust member fixedly coupled to a base member;
a shaft fixedly coupled to at least one of the lower thrust member and the base member;
a sleeve disposed on an upper portion of the lower thrust member and rotatably installed on the shaft;
a rotor hub coupled to the sleeve to thereby rotate together with the sleeve;
an upper thrust member fixedly coupled to an upper end portion of the shaft and forming a liquid-vapor interface together with the sleeve; and
a cover member fixedly coupled to the shaft so as to be disposed on an upper portion of the upper thrust member,
wherein the upper thrust member includes a stepped jaw part having a lower surface supported by an upper surface of the shaft and an upper surface pressed by the cover member, so as to increase coupling strength with the shaft.
2. The spindle motor of claim 1, wherein the sleeve has an inclination part formed in an upper end portion thereof so as to form the liquid-vapor interface together with the upper thrust member, the inclination part having an outer diameter larger in an upper portion thereof than in a lower portion thereof.
3. The spindle motor of claim 2, wherein the upper thrust member includes a body having an inner surface bonded to the shaft, a protrusion part extended from the body to thereby form the liquid-vapor interface together with the inclination part, and the stepped jaw part extended in an inner radial direction from the inner surface of the body.
4. The spindle motor of claim 3, wherein the shaft includes a depression groove formed to be depressed from an outer peripheral surface thereof so as to separate lubricating fluid filling a bearing clearance formed by the sleeve and the shaft into two parts.
5. The spindle motor of claim 4, wherein the sleeve includes a communication hole disposed to face the depression groove to thereby provide communication between the depression groove and the outside of the sleeve.
6. The spindle motor of claim 1, wherein the rotor hub includes:
a rotor hub body including an insertion part formed therein, the insertion part including the upper thrust member insertedly disposed in an inner portion thereof;
a mounting part extended from an edge of the rotor hub body and including a magnet assembly mounted on an inner surface thereof; and
an extension part extended in an outer radial direction from an edge of the mounting part.
7. The spindle motor of claim 1, wherein an outer surface of the upper thrust member and an inner surface of the rotor hub disposed to face the outer surface of the upper thrust member have a clearance of 0.3 mm or less formed therebetween.
8. A spindle motor comprising:
a lower thrust member fixedly coupled to a base member;
a shaft fixedly coupled to on at least one of the lower thrust member and the base member;
a sleeve disposed on an upper portion of the lower thrust member and rotatably installed on the shaft;
a rotor hub coupled to the sleeve to thereby rotate together with the sleeve;
an upper thrust member fixedly coupled to an upper end portion of the shaft and forming a liquid-vapor interface together with the sleeve; and
a cover member fixedly coupled to the shaft so as to be disposed on an upper portion of the upper thrust member,
wherein the shaft includes a step part formed in an upper end portion thereof, the step part supporting a lower surface of the upper thrust member so as to increase coupling strength with the upper thrust member.
9. The spindle motor of claim 8, wherein the upper thrust member has an upper surface disposed at a position higher than that of an upper surface of the shaft and pressed by the cover member.
10. A spindle motor comprising:
a lower thrust member fixedly coupled to a base member;
a shaft fixedly coupled to at least one of the lower thrust member and the base member;
a sleeve disposed on an upper portion of the lower thrust member and rotatably installed on the shaft;
a rotor hub coupled to the sleeve to thereby rotate together with the sleeve;
an upper thrust member fixedly coupled to an upper end portion of the shaft and forming a liquid-vapor interface together with the sleeve; and
a cover member fixedly coupled to the shaft so as to be disposed on an upper portion of the upper thrust member,
wherein an upper surface of the shaft and an upper surface of the upper thrust member are coplanarly disposed and pressed by the cover member.