Thomas J Graham

US Patent:

6377442, Apr 23, 2002

Filed:

Sep 21, 2000

Appl. No.:

09/668018

Inventors:

Thomas F. Strange - Easley SC
Timothy R. Marshall - Pickens SC
Thomas V. Graham - Greenville SC

Assignee:

Pacesetter, Inc. - Sunnyvale CA

International Classification:

H01G 904

US Classification:

361508, 361523, 361509, 361512, 361516

Abstract:

The present invention is directed to an electrolytic capacitor having a novel floating anode between the cathode and the powered anode of the capacitor, resulting in a single capacitor having a working voltage double that of the formation voltage of the powered anode. The floating anode acts as cathode to the powered anode and as an anode to the cathode, such that the capacitor according to the present invention supports half the working voltage between the cathode and the floating anode and half the working voltage between the floating anode and the powered anode. The arrangement of the cathode, floating anode and powered anode according to the present invention results in a single capacitor with half the capacitance and twice the voltage of a single anode device.

US Patent:

6648927, Nov 18, 2003

Filed:

May 25, 2001

Appl. No.:

09/865975

Inventors:

Gregory Scott Fandrich - Easley SC
Thomas Flavian Strange - Easley SC
Thomas V. Graham - Greenville SC

Assignee:

Pacesetter, Inc. - Sunnyvale CA

International Classification:

H01G 900

US Classification:

29 2503, 264319, 26427218

Abstract:

The present invention is directed to a method of encasing electrolytic capacitor stacks or wound rolls to form an external package. First, a plastic sheet is heated to its soft transition temperature. Next, the plastic sheet is draped over a preassembled capacitor stack or wound roll. Then, a vacuum is applied to the capacitor stack or wound roll, such that the sheet is formed around the stack or wound roll. Finally, the plastic sheet is allowed to cool. This process results in a vacuum formed plastic capacitor case assembly which minimizes wasted volume in the capacitor package and minimizes capacitor assembly time.

US Patent:

6736956, May 18, 2004

Filed:

May 7, 2001

Appl. No.:

09/851298

Inventors:

Ralph Jason Hemphill - Liberty SC
Thomas V. Graham - Greenville SC
Thomas Flavian Strange - Easley SC

Assignee:

Pacesetter, Inc. - Sunnyvale CA

International Classification:

B23H 1100

US Classification:

205640, 205666, 205674, 205223, 205324, 205221, 216 41, 216 47, 361509

Abstract:

The present invention is directed to a method of etching anode foil in a non-uniform manner which increases the overall capacitance gain of the foil while retaining foil strength. In particular, by using a mask to protect a mesh grid of the foil from further etching, a previously etched foil can be further etched, prior to the widening step. Alternatively, the mask may be used in the initial etch, eliminating the need for the second process. In effect the foil may be etched to a higher degree in select regions, leaving a web of more lightly etched foil defined by the mask to retain strength. According to the present invention, the foil is placed between two masks with a grid of openings which expose the foil in these areas to the etching solution. The exposed area can be as little as 10% of the total foil to as much as 95% of the total foil, preferably 30% to 70% of the total foil area. The pattern is configured in such a way that the enhanced area does not create large scale strength defects such as perforation holes and is held in a pattern such as a hexagonal array, random array or radial burst array, such that the exposed area perimeter can be round, square, hexagonal, or triangular.

US Patent:

6802954, Oct 12, 2004

Filed:

Jul 18, 2002

Appl. No.:

10/199846

Inventors:

Ralph Jason Hemphill - Liberty SC
Thomas V. Graham - Greenville SC
Thomas F. Strange - Easley SC

Assignee:

Pacesetter, Inc. - Sunnyvale CA

International Classification:

B23H 1100

US Classification:

205640, 205112, 205674, 205685, 205324, 205666

Abstract:

The present invention is directed to a method of creating porous anode foil for use in multiple anode stack configuration electrolytic capacitors, producing a pore structure that is microscopic in pore diameter and spacing, allowing for increased energy density with a minimal increase in ESR. Initially, an anode metal foil is etched, according to a conventional etch process, to produce an enlargement of surface area. The etched foil is then placed into the electrochemical drilling solution of the present invention. Alternatively, the etched foil may be masked, so that only small areas of the etched foil are exposed, prior to being placed in the electrochemical drilling solution. A DC power supply is used to electrochemically etch the masked or unmasked foil in the electrochemical drilling solution of the present invention such that pores on the order of a few microns diameter are produced through the foil. The electrochemical drilling solution of the present invention consists of 1 to 15% by weight sodium chloride, preferably 5% by weight, and 10 to 5000 PPM of a surface passivator, such as sodium nitrate or phosphoric acid, preferably 500 PPM. Finally, the foil pores are widened and the foil is formed to the intended use voltage according to conventional widening and forming processes.

US Patent:

6815306, Nov 9, 2004

Filed:

Feb 13, 2002

Appl. No.:

10/075711

Inventors:

Thomas F. Strange - Easley SC
Timothy R. Marshall - Pickens SC
Thomas V. Graham - Greenville SC

Assignee:

Pacesetter, Inc. - Sunnyvale CA

International Classification:

H01L 2120

US Classification:

438379, 438171, 438190, 438238, 361503, 361502

Abstract:

The present invention is directed to an electrolytic capacitor having a novel floating anode between the cathode and the powered anode of the capacitor, resulting in a single capacitor having a working voltage double that of the formation voltage of the powered anode. The floating anode acts as cathode to the powered anode and as an anode to the cathode, such that the capacitor according to the present invention supports half the working voltage between the cathode and the floating anode and half the working voltage between the floating anode and the powered anode. The arrangement of the cathode, floating anode and powered anode according to the present invention results in a single capacitor with half the capacitance and twice the voltage of a single anode device.