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US4082980A Expired / Lapsed US ⏱️ 0.0 years remaining

Spark plug cap providing a capacitor in parallel with the spark cap

Assignee: Murata Manufacturing Co Ltd
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Filing: 1976-02-09
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Granted: 1978-04-04
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Expires: 1996-02-09
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Abstract

Abstract A spark plug cap for use on a spark plug of an internal combustion engine to much intensify sparking across the gap between central and ground electrodes of the spark plug. The spark plug cap includes an insulating body having a connector provided at its one end for mechanically connecting the cap to the spark plug. An electrical conductor extends through the insulating body for supplying high-tension ignition current to the central electrode of the spark plug. At least one capacitor unit is supported within the insulating body and electrically connected across the gap between the spark plug electrodes.

Inventors

  • 👤 Masazi Yoshikawa
  • 👤 Tomoe Sawada

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 20:59
CPC Classifications
H; H01; H01T; H01T13/00; H01T13/02; H01T13/04; H01T13/05; H01T13/06

Claims Analysis

Total Claims: 26
Claim 1
Independent Claim 133 words
A spark plug cap for electrically and mechanically connecting a spark plug to an ignition current supply cord to intensify sparking across the gap between central and ground electrodes of the spark plug, which comprises: an insulating body, said insulating body including means for mechanically connecting said cap to said spark plug and terminal means adapted to be connected to said supply cord; electrically conductive means extending through said insulating body to electrically connect said terminal means to said central electrode of said spark plug; and at least one capacitor unit embedded essentially entirely within said body and electrically connected in parallel to said spark gap, said capacitor unit comprising an essentially flat capacitor having a flat dielectric base and a pair of electrodes attached on the opposite sides of said dielectric base.
Claim 2
Dependent Claim 133 words
A spark plug cap for electrically and mechanically connecting a spark plug to an ignition current supply cord to intensify sparking across the gap between central and ground electrodes of the spark plug, which comprises: an insulating body, said insulating body including means for mechanically connecting said cap to said spark plug and terminal means adapted to be connected to said supply cord; electrically conductive means extending through said insulating body to electrically connect said terminal means to said central electrode of said spark plug; and at least one capacitor unit embedded essentially entirely within said body and electrically connected in parallel to said spark gap, said capacitor unit comprising an essentially flat capacitor having a flat dielectric base and a pair of electrodes attached on the opposite sides of said dielectric base.
Claim 3
Dependent Claim 44 words
A spark plug cap according to claim 1 wherein said insulating body is formed with a lateral recess adapted to retain said capacitor unit, said lateral recess being filled with an insulating material to surround said capacitor unit and retain said capacitor unit therein.
Claim 4
Dependent Claim 33 words
A spark plug cap according to claim 2 wherein said insulating body is made of a member selected from the group consisting of fiber reinforced plastics, epoxy resin, silicone rubber and ceramic material.
Claim 5
Dependent Claim 27 words
A spark plug cap according to claim 2 which includes a plurality of capacitor units and an equal number of lateral recesses for supporting said capacitor units.
Claim 6
Dependent Claim 27 words
A spark plug cap according to claim 4 wherein said plurality of capacitor units are arranged with generally geometrical symmetry with respect to said electrically conductive means.
Claim 7
Dependent Claim 37 words
A spark plug cap according to claim 1 wherein said cap capacitor electrode is electrically coupled to said electrically conductive means and the other capacitor electrode is electrically coupled to the ground electrode of the spark plug.
Claim 8
Dependent Claim 57 words
A spark plug cap according to claim 6 which further includes: an electrically conductive lead embedded in said insulating body, said electrically conductive lead coupled at one end to said other capacitor electrode; and an electrically conductive coil spring electrically coupling the other end of said electrically conductive lead with the ground electrode of said spark plug.
Claim 9
Dependent Claim 23 words
A spark plug cap according to claim 1 wherein adjacent turns of said coil spring are spaced apart more than about 5 millimeters.
Claim 10
Dependent Claim 27 words
A spark plug cap according to claim 1 which further includes a generally resilient sleeve adapted to surround the spark plug when said cap is attached thereto.
Claim 11
Dependent Claim 20 words
A spark plug cap according to claim 7 wherein adjacent turns of said coil spring are in essentially intimate contact.
Claim 12
Dependent Claim 66 words
A spark plug cap according to claim 1 wherein one of said capacitor electrodes is electrically coupled to said electrically conductive means and the other capacitor electrode is electrically coupled to the ground electrode of the spark plug by generally hook-shaped leaf springs engageable with the inner wall of a plug receiving cavity formed in the internal combustion engine in which the spark plug is mounted.
Claim 13
Dependent Claim 138 words
A spark plug cap for electrically and mechanically connecting a spark plug to an ignition current supply cord to intensify sparking across the gap between central and ground electrodes of the spark plug, which comprises: an insulating body, said insulating body having means for mechanically connecting said cap to said spark plug and terminal means adapted to be connected to said supply cord; electrically conductive means extending through said insulating body to electrically connect said terminal means to the central electrode of said spark plug; and at least one generally cylindrical capacitor unit embedded within said insulating body and electrically connected in parallel to said spark plug gap, said capacitor unit including an essentially cylindrical dielectric through which said conductive means extends and a pair of electrodes positioned on the opposite end faces of said cylindrical dielectric base.
Claim 14
Dependent Claim 138 words
A spark plug cap for electrically and mechanically connecting a spark plug to an ignition current supply cord to intensify sparking across the gap between central and ground electrodes of the spark plug, which comprises: an insulating body, said insulating body having means for mechanically connecting said cap to said spark plug and terminal means adapted to be connected to said supply cord; electrically conductive means extending through said insulating body to electrically connect said terminal means to the central electrode of said spark plug; and at least one generally cylindrical capacitor unit embedded within said insulating body and electrically connected in parallel to said spark plug gap, said capacitor unit including an essentially cylindrical dielectric through which said conductive means extends and a pair of electrodes positioned on the opposite end faces of said cylindrical dielectric base.
Claim 15
Dependent Claim 33 words
A spark plug cap according to claim 1 wherein said insulating body is made of a member selected from the group consisting of fiber reinforced plastics, epoxy resin, silicone rubber and ceramic material.
Claim 16
Dependent Claim 38 words
A spark plug cap according to claim 1 wherein one electrode of said capacitor unit is electrically connected to said electrically conductive means and the other electrode is electrically coupled to the ground electrode of the spark plug.
Claim 17
Dependent Claim 75 words
A spark plug cap according to claim 14 which further includes: a first electrically conductive lead electrically coupling said one capacitor electrode to said electrically conductive means; a second electrically conductive lead embedded in said insulating body, said second lead having one end electrically coupled to said other capacitor electrode; and an electrically conductive coil spring electrically coupling the other end of said second electrically conductive lead with the ground electrode of said spark plug.
Claim 18
Dependent Claim 23 words
A spark plug cap according to claim 15 wherein adjacent turns of said coil spring are spaced apart more than about 5 millimeters.
Claim 19
Dependent Claim 20 words
A spark plug cap according to claim 15 wherein adjacent turns of said coil spring are in essentially inimate contact.
Claim 20
Dependent Claim 161 words
A spark plug cap for electrically and mechanically connecting a spark plug to an ignition current supply cord to intensify sparking across the gap between central and ground electrodes of the spark plug, which comprises: an insulating body, said insulating body having means for mechanically connecting said cap to said spark plug and terminal means adapted to be connected to said supply cord; electrically conductive means extending through said insulating body to electrically connect said terminal means to the central electrode of said spark plug; at least one capacitor unit supported within said body and electrically connected in parallel to said spark gap, one electrode of said capacitor unit being electrically connected to said electrically conductive means; an electrically conductive lead connected to the other capacitor electrode and adapted to be electrically coupled to the ground electrode of the spark plug; and an electrically conductive coil spring electrically connecting said electrically conductive lead with the ground electrode of said spark plug.
Claim 21
Dependent Claim 161 words
A spark plug cap for electrically and mechanically connecting a spark plug to an ignition current supply cord to intensify sparking across the gap between central and ground electrodes of the spark plug, which comprises: an insulating body, said insulating body having means for mechanically connecting said cap to said spark plug and terminal means adapted to be connected to said supply cord; electrically conductive means extending through said insulating body to electrically connect said terminal means to the central electrode of said spark plug; at least one capacitor unit supported within said body and electrically connected in parallel to said spark gap, one electrode of said capacitor unit being electrically connected to said electrically conductive means; an electrically conductive lead connected to the other capacitor electrode and adapted to be electrically coupled to the ground electrode of the spark plug; and an electrically conductive coil spring electrically connecting said electrically conductive lead with the ground electrode of said spark plug.
Claim 22
Dependent Claim 23 words
A spark plug cap according to claim 18 wherein adjacent turns of said coil spring are spaced more than about 5 millimeters apart.
Claim 23
Dependent Claim 20 words
A spark plug cap according to claim 18 wherein adjacent turns of said coil spring are in essentially intimate contact.
Claim 24
Dependent Claim 156 words
A spark plug cap for electrically and mechanically connecting a spark plug to an ignition current supply cord to intensify sparking across the gap between central and ground electrodes of the spark plug, which comprises: an insulating body, said insulating body having means for mechanically connecting said cap to said spark plug and terminal means adapted to be connected to said supply cord; electrically conductive means extending through said insulating body to electrically connect said terminal means to the central electrode of said spark plug; at least one capacitor unit supported within said insulating body and electrically connected in parallel to said spark gap; and grounding means for electrically coupling said capacitor unit to the ground electrode of said spark plug, said grounding means including at least one electrically conductive spring member adapted to engage the inner wall of a plug receiving cavity formed in the internal combustion engine in which the spark plug is mounted.
Claim 25
Dependent Claim 156 words
A spark plug cap for electrically and mechanically connecting a spark plug to an ignition current supply cord to intensify sparking across the gap between central and ground electrodes of the spark plug, which comprises: an insulating body, said insulating body having means for mechanically connecting said cap to said spark plug and terminal means adapted to be connected to said supply cord; electrically conductive means extending through said insulating body to electrically connect said terminal means to the central electrode of said spark plug; at least one capacitor unit supported within said insulating body and electrically connected in parallel to said spark gap; and grounding means for electrically coupling said capacitor unit to the ground electrode of said spark plug, said grounding means including at least one electrically conductive spring member adapted to engage the inner wall of a plug receiving cavity formed in the internal combustion engine in which the spark plug is mounted.
Claim 26
Dependent Claim 20 words
A spark plug cap according to claim 21 wherein each electrically conductive spring member comprises a generally hook-shaped leaf spring.

References Cited (Backward Citations)

US2376362A Cited
FR1307681A Cited
US3683232A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-04-03 1981-10-03 1982-04-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-04-03 1985-10-03 1986-04-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-04-03 1989-10-03 1990-04-04 $7700.00 Window Closed / Lapsed

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