1. A spark plug comprising:
an insulator having a through hole in an axial direction of said spark plug and comprising alumina ceramics;
a center electrode partially inserted in a front end of the through hole;
an external terminal partially inserted in a rear end of the through hole; and
a conductive seal provided between said external terminal and said center electrode in said through hole,
wherein said conductive seal contains base glass, a conductive filler and from 0 to 10 weight % of an insulating filler,
said base glass contains:
a Si component in an amount of from 55 to 65 weight %, in terms of SiO2, a B component in an amount of from 22 to 35 weight %, in terms of B2O3, a Ca component in an amount of from 0.2 to 2 weight %, in terms of CaO, an Al component in an amount of 2 weight % or less, in terms of Al2O3, and a Na component and a K component in a total amount of from 4 to 8 weight %, in terms of Na2O and K2O, respectively, and
said base glass contains both said Na component and said K component.
2. The spark plug as claimed in claim 1, wherein a weight of said Na component contained in said base glass, in terms of Na2O, is no less than a weight of said K component contained in said base glass, in terms of K2O.
3. The spark plug as claimed in claim 1, wherein said conductive seal does not contain an insulating filler.
4. The spark plug as claimed in claim 1, wherein a total of a weight of said Si component, in terms of SiO2, and a weight of said B component, in terms of B2O3, is from 86 to 94 weight %, based on a weight of said base glass.
5. A spark plug comprising:
an insulator having a through hole in an axial direction of said spark plug;
a first conductive seal provided in said through hole;
a second conductive seal provided in said through hole;
a center electrode partially inserted in a front end of said through hole and bonded to said first conductive seal;
an external terminal partially inserted in a rear end of said through hole and bonded to said second conductive seal; and
a resistor provided between said first conductive seal and said second conductive seal,
wherein said second conductive seal contains base glass, a conductive filler, and 10 weight % or less, but more than 0 weight % of an insulating filler, and
said first conductive seal contains base glass, a conductive filler, and an insulating filler in an amount (including 0 weight %) smaller than that of said insulating filler contained in said second conductive seal.
6. The spark plug as claimed in claim 5, wherein said first conductive seal does not contain an insulating filler.
7. The spark plug as claimed in claim 5,
wherein said insulator comprises alumina ceramics,
the base glasses of said first and second conductive seal each independently contains:
a Si component in an amount of from 55 to 65 weight %, in terms of SiO2;
a B component in an amount of from 22 to 35 weight %, in terms of B2O3;
a Ca component in an amount of from 0.2 to 2 weight %, in terms of CaO;
an Al component in an amount of 2 weight % or less, in terms of Al2O3; and
a Na component and a K component in a total amount of from 4 to 8 weight %, in terms of Na2O and K2O, respectively, and
said base glasses each independently contains both said Na component and said K component.
8. The spark plug as claimed in claim 7, wherein in both of said first and second conductive seals, a weight of said Na component contained in said base glass, in terms of Na2O, is no less than a weight of said K component contained in said base glass, in terms of K2O.
9. The spark plug as claimed in claim 7, wherein in both of said first and second conductive seals, a total weight of said Si component, in terms of SiO2, and said B component, in terms of B2O3, is from 86 to 94 weight %, based on a weight of said base glass.
10. The spark plug as claimed in claim 1, wherein the relationship W1\u2267W2\u2267W15 is satisfied, wherein the weight of the Na component in the base glass, as converted to Na2O, is given by W1 and the weight of the K component, as converted to K2O, is given by W2.
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 method of forwarding diagnostic messages among members of groups in a data processing system while the members are executing protocols, comprising the steps of:
attaching a header to the message, the header including the following header fields:
(1) a protocol handle identifying the originator protocol from which the request originated; and
(2) a forwarding handle of null value identifying, if present, an original protocol which is the current parent of the protocol;
sending the diagnostic message to the member of the group identified by the forwarding handle which originated the protocol.
2. The method of claim 1, further including the step of:
including in header to the message an identifier of the member and group which originated the message.
3. The method of claim 1, further including the step of:
including in the header to the message an identifier of the member and group of the parent protocol originator, if any, which originated the message.
4. A computer system including a plurality of groups, each group composed of one or more members, said computer system forwarding diagnostic messages among the members of the groups and including:
means for forming a message including in its header message the following header fields:
(1) a protocol handle identifying the originator protocol from which the request originated; and
(2) a forwarding handle of null value identifying, if present, an original protocol which is current parent of the protocol:
means for sending the diagnostic message to the member of the group identified by the forwarding handle which originated the protocol.
5. The computer system of claim 4, which said means for forming a header message further includes:
means for including in the header to the message an identifier of the member and group which originated the diagnostic message.
6. The computer system of claim 4, wherein said means for forming a header message further includes:
means for including in the header to the message an identifier of the member and group of the parent protocol originator, if any, which originated the diagnostic message.
7. A computer memory element containing stored in signal bearing media a diagnostic message to be forwarded among members of one or more groups in a computer system and utilized therein, the stored diagnostic message containing a header message including the following header fields:
(1) a protocol handle identifying the originator protocol from which the request originated;
(2) a forwarding handle of null value identifying, if present, an original protocol which is the current parent of the protocol; and
instructions for sending the diagnostic message to the member of the group identified by the forwarding handle which originated the protocol.
8. The computer memory element of claim 7, wherein the header message contained in the stored diagnostic message further includes:
an identifier of the member and group which originated the diagnostic message.
9. The computer memory element of claim 7, wherein the header message contained in the stored diagnostic message further includes:
an identifier of the member and group of the parent protocol originator, if any, which originated the diagnostic message.
10. A method of forwarding diagnostic messages among members of groups in a data processing system to those members executing protocols implicated by the message, comprising the steps of:
forwarding as part of the diagnostic message a header including the following header fields:
(1) a protocol handle identifying the originator protocol from which the request originated; and
(2) a forwarding handle identifying, if present, a protocol which is the current parent of the protocol;
examining the forwarding handle at each member of the groups of the system to ascertain if that member was a parent of the protocol identified in the forwarding handle field of the header of the diagnostic message;
forwarding another diagnostic message having a header including the following header fields:
(1) a protocol handle identifying the originator protocol from which the request originated; and
(2) a forwarding handle identifying, if present, a protocol which is the current parent of the protocol.
11. The method of claim 10, further including the step of:
sending the diagnostic message to the member of the group identified by the forwarding handle of another diagnostic message.
12. The method of claim 11, further including the step of:
repeating the steps of claims 12 and 14 until the forwarding handle of the header field indicates the protocol is an original protocol.