EP0146870A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Thermal head
Assignee: Hitachi Ltd
•
Filing: 1984-12-11
•
Granted: —
•
Expires: 2004-12-11
Abstract
Abstract A thermal head comprises a heat accumulating member (2) disposed on a substrate (1), a plurality of heating resistors (3) juxtaposed on the heat accumulating member (2) in a manner to be spaced from each other, electrodes (4) for supplying electric power to the heating resistors (3), and a protective member (5) for preventing oxidation and wear of the heating resistors (3) and the electrodes (4), these constituents being formed as layers. When the electric power is supplied to the electrodes (4), heat is generated by a heating portion (3a) of the heating resistor (3) corresponding to the electrodes (4), and it is transmitted to a head surface (6a) via a thermally conductive member (7) disposed in a printing dot portion (6a) of the protective member (5). The heat from the printing dot portion (6a) is used for effecting printing on a medium to-be-recorded through a thermosensitive sheet (9) which lies in contact with the head surface (6a).
Inventors
- 👤 Kazuya Higeta
- 👤 Kazumasa Fujioka
- 👤 Takeo Nemoto
- 👤 Takahiro Daikoku
- 👤 Isao Nakajima
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 22:31
CPC Classifications
B; B41; B41J; B41J2/00; B41J2/315; B41J2/32; B41J2/345
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
131 words
A thermal head having a substrate (1), a heat accumulating member (2) which is disposed on the substrate (1), a plurality of heating resistors (3) which are juxtaposed on the heat accumulating member (2) in a manner to be spaced from each other, electrodes (4) which supply electric power to the heating resistors (3), and a protective member (5) which prevents oxidation and wear of the heating resistors (3) and the electrodes (4), characterized in that said protective member (5) comprises printing dot portions (6a) which are formed independently of each other, which are made of thermally conductive members (7) higher in thermal conductivity than the other part of said protective member (5), and surfaces of which are even with a head surface (6) other than said printing dot portions (6a).
Claim 2
Dependent Claim
131 words
A thermal head having a substrate (1), a heat accumulating member (2) which is disposed on the substrate (1), a plurality of heating resistors (3) which are juxtaposed on the heat accumulating member (2) in a manner to be spaced from each other, electrodes (4) which supply electric power to the heating resistors (3), and a protective member (5) which prevents oxidation and wear of the heating resistors (3) and the electrodes (4), characterized in that said protective member (5) comprises printing dot portions (6a) which are formed independently of each other, which are made of thermally conductive members (7) higher in thermal conductivity than the other part of said protective member (5), and surfaces of which are even with a head surface (6) other than said printing dot portions (6a).
Claim 3
Dependent Claim
41 words
A thermal head according to claim 1, characterized in that said thermally conductive member (7) is disposed so as to be thermally joined to said heating resistor (3) with one face thereof held in direct contact with said heating resistor (3).
Claim 4
Dependent Claim
34 words
A thermal head according to claim 1 or 2, characterized in that said thermally conductive member (7) is disposed with an electrically insulating member interposed between one face thereof and said heating resistor (3).
Claim 5
Dependent Claim
50 words
A thermal head according to any of claims 1 to 3, characterized in that a surface of said thermally conductive member (7) on a side thereof at a surface of said printing dot portion (6a) differs in shape from a surface on a side thereof at said heating resistor (3).
Claim 6
Dependent Claim
53 words
A thermal head according to claim 4, characterized in that the shape of the surface of said thermally conductive member (7) on the side (7b) at the surface of said printing dot portion (6a) is made smaller than the shape of the surface thereof on the side (7a) at said heating resistor (3a).
Claim 7
Dependent Claim
40 words
A thermal head according to claim 5, characterized in that said thermally conductive member (7) is so formed that a sectional shape thereof becomes smaller stepwise from the heating resistor side toward the printing dot portion surface side (Fig. 5,6).
Claim 8
Dependent Claim
40 words
A thermal head according to claim 5, characterized in that said thermally conductive member (7) is so formed that a sectional shape thereof becomes smaller continuously from the heating resistor side toward the printing dot portion surface side (Fig. 7,8).
Claim 9
Dependent Claim
33 words
A thermal head according to any of claims 1 to 7, characterized in that a sealing member (8) for shielding said heating resistors (3) and said electrodes (4) from external air is comprised.
Claim 10
Dependent Claim
30 words
A thermal head according to claim 8, characterized in that said sealing member (8) is disposed so as to cover said electrodes (4) and said heating resistors (3) (Fig. 11).
Claim 11
Dependent Claim
31 words
A thermal head according to claim 8, characterized in that said sealing member (8) is disposed so as to cover said electrodes (4) and said thermally conductive members (7) (Fig. 12).
Claim 12
Dependent Claim
32 words
A thermal head according to claim 8, characterized in that said sealing member (8) is disposed so a to cover said protective member (5) and said thermally conductive members (7) (Fig. 13).
Claim 13
Dependent Claim
24 words
A thermal head according to any of claims 8 to 11, charcterized in that said sealing member is made of an electrically insulating material.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.