Stencil printing machine

• US 7,117,786 B2
• Filed: 08/27/2004
• Issued: 10/10/2006
• Est. Priority Date: 08/27/2003
• Status: Expired due to Fees

• Current Assignee: RISO Kagaku Corporation
• Original Assignee: RISO Kagaku Corporation
• Inventors: Kamano, Hirokazu, Nakamura, Akira, Naitou, Taku
• Primary Examiner(s): Hirshfeld, Andrew H.
• Assistant Examiner(s): ZIMMERMAN, JOSHUA D
• Application Number:
  US10/927,585
• Publication Number:
  US 20050045054A1
• Time in Patent Office: 774 Days
• Field of Search: 101/119
• US Class Current: 101/119
• CPC Class Codes: B41L 13/18 Inking units

Abstract

A stencil printing machine has a rotatable printing drum including an outer peripheral wall of ink impermeable material. A stencil paper is mounted on the surface of the outer peripheral wall. An ink supplying mechanism includes an ink supplying unit in the outer peripheral wall of the printing drum and supplies ink to the surface of the outer peripheral wall. A pressure roller presses a fed print sheet against the outer peripheral wall. When an initial printing operation is performed after a stencil paper is mounted on the printing drum, the ink supplying mechanism is caused to supply the surface of the outer peripheral wall, in advance, with an amount of ink which is larger than an amount of ink which is supplied for second and proceeding printing operations.

Claims

1. A stencil printing machine, comprising:

a rotatable printing drum including an outer peripheral wall of ink impermeable material, wherein a stencil paper is mounted on the surface of the outer peripheral wall;

an ink supplying mechanism including an ink supplying unit in the outer peripheral wall of the printing drum, configured to supply ink from the ink supplying unit to the surface of the outer peripheral wall;

a pressure roller configured to press a fed print medium against the outer peripheral wall;

an ink volume timer for measuring a time needed for supplying ink; and

a controller, for initial printing operation after stencil paper is mounted on the printing drum, for supplying an amount of ink which is larger than an amount of ink which is supplied for second and proceeding printing operations based on time data from the ink volume timer while rotating the printing drum at a speed which is slower than a speed at which second and proceeding printing operations are performed.

2. The stencil printing machine according to claim 1, wherein an amount of ink which is supplied for an initial printing operation after a stencil paper is mounted on the printing drum is larger than an average amount of ink which is held in the inner surface of a stencil paper after an printing operation is completed.

3. The stencil printing machine according to claim 1, wherein the ink supplying unit is configured to supply ink between the stencil paper and the surface of the outer peripheral wall from the inside of the printing drum without exposing the ink to the atmosphere.

4. The stencil printing machine according to claim 1, wherein the ink supplying mechanism includes a conduit configured to supply ink to the ink supplying unit from the inside of the printing drum without exposing the ink to the atmosphere.

5. A stencil printing machine, comprising:

a rotatable printing drum including an outer peripheral wall of ink impermeable material, wherein a stencil paper is mounted on the surface of the outer peripheral-wall;

an ink supplying mechanism including an ink supplying unit in the outer peripheral wall of the printing drum, configured to supply ink from the ink supplying unit to the surface of the outer peripheral wall; and

a pressure roller configured to press a fed print medium against the outer peripheral wall;

an ink volume timer for measuring a time needed for supplying ink;

a timer for measuring a time period for which the printing drum has been left as it is; and

a controller, for initial printing operation after a time period from a time at which the printing drum is caused to stop operating through a time at which the initial printing operation is started exceeds a prescribed length of time, for supplying an amount of ink which is larger than an amount of ink which is supplied for second and proceeding printing operations based on time data from the ink volume timer and the timer while rotating the printing drum at a speed which is slower than a speed at which second and proceeding printing operations are performed.

6. The stencil printing machine according to claim 5, wherein an amount of ink which is supplied for an initial printing operation after the printing drum has been left as it is for along time is larger than an average amount of ink which is held in the inner surface of a stencil paper after an printing operation is completed.