Claims
- 1. A ribbon cartridge for a typewriter or other printing machine of the type having a single drive shaft, and in which the cartridge comprises a casing; a ribbon; a take-up spool for the ribbon; a drive roller; and a pressure roller, which can be coupled to the single drive shaft for the unidirectional advance movement of the ribbon, and transmission mechanism between one of said drive roller and pressure roller and the take-up spool, wherein said transmission mechanism comprises a toothed wheel and the take-up spool has a hub member coaxial with the toothed wheel, and a friction clutch between the hub member and the toothed wheel, wherein said toothed wheel comprises a sleeve which projects axially from the toothed wheel and two shoulders which are positioned in diametrically opposite relationship to the sleeve, wherein said hub member includes an internal seat which is guided on the sleeve, and an outside circular groove adjacent to the internal seat;
- wherein said friction clutch comprises a resilient ring which is mounted between said two shoulders of said toothed wheel and is housed in the outside circular groove of said hub member, and
- wherein said two shoulders cause the resilient ring to be put in traction and to assume an elongate shape provided with two sections which engage frictionally the outside circular groove of said hub member.
- 2. A ribbon cartridge according to claim 1 and to be used with a typewriter, wherein said single drive shaft comprises a drive pinion, wherein said transmission mechanism does not interfere with the ribbon wound onto the take-up spool, and further comprises a drive gear which, when the cartridge is mounted on the typewriter, is engageable with said drive pinion; a first driven pinion fixed coaxial with said drive gear; an intermediate gear which is in mesh with said first driven pinion; and a second driven pinion fixed coaxial with said pressure roller; wherein said intermediate gear is in mesh with said toothed wheel for transmitting the drive motion to the take-up spool by means of the friction clutch and wherein said intermediate gear is in mesh with said second pinion for transmitting the drive motion to said pressure roller which presses the ribbon against the drive roller for incremental advance movement of said ribbon.
- 3. A ribbon cartridge according to claim 1, wherein the toothed wheel comprises an internal cylindrical seat for housing said two shoulders, said sleeve and said resilient ring.
- 4. A ribbon cartridge according to claim 1, wherein said hub member is a portion of said take-up spool.
Priority Claims (1)
Number |
Date |
Country |
Kind |
67254 A/83 |
Mar 1983 |
ITX |
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Parent Case Info
This application is a division, of application Ser. No. 582,738, filed Feb. 23, 1984, now U.S. Pat. No. 4,669,902 issued June 2, 1987.
US Referenced Citations (12)
Foreign Referenced Citations (3)
Number |
Date |
Country |
2757993 |
Dec 1977 |
DEX |
2901058 |
Dec 1979 |
DEX |
2003832 |
Aug 1978 |
GBX |
Divisions (1)
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Number |
Date |
Country |
Parent |
582738 |
Feb 1984 |
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