Image recording apparatus

Abstract

To record images accurately regardless of rigidity and size of a recording medium, each rear end clamp has a clamp rubber element for engaging a variable margin of the recording medium mounted peripherally of the recording drum. The margin is varied according to the rigidity of the recording medium. The margin is enlarged when the recording medium is highly rigid, and reduced when the recording medium is low in rigidity.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of illustrating the invention, there are shown in the drawings several forms which are presently preferred, it being understood, however, that the invention is not limited to the precise arrangement and instrumentalities shown.

FIG. 1 is a schematic side view of an image recording apparatus according to this invention;

FIG. 2 is a perspective view showing a recording drum along with forward end clamps and rear end clamps;

FIG. 3 is a developed view of the peripheral surface of the recording drum;

FIG. 4A is a schematic view of a rear end clamp;

FIG. 4B is a schematic view of the rear end clamp;

FIG. 5A is a schematic view of the rear end clamp;

FIG. 5B is a schematic view of the rear end clamp;

FIG. 6A is a schematic view showing a relationship between a clamping bolt and a clamp groove;

FIG. 6B is a schematic view showing the relationship between the clamping bolt and clamp groove;

FIG. 6C is a schematic view showing the relationship between the clamping bolt and clamp groove;

FIG. 7A is an explanatory view showing a clamp rubber element of a rear end clamp for fixing single-mounting and double-mounting plates;

FIG. 7B is an explanatory view showing the clamp rubber element of the rear end clamp for fixing single-mounting and double-mounting plates;

FIG. 8A is an explanatory view showing a clamp rubber element of a rear end clamp for fixing single-mounting and double-mounting plates;

FIG. 8B is an explanatory view showing the clamp rubber element of the rear end clamp for fixing single-mounting and double-mounting plates;

FIG. 9 is a flow chart of a plate mounting operation;

FIG. 10 is a flow chart of a clamp position reading operation; and

FIG. 11 is a flow chart of another clamp position reading operation.

Claims

1. An image recording apparatus comprising: a recording drum for supporting a recording medium mounted peripherally thereof;forward end clamps for fixing a forward end of the recording medium mounted peripherally of said recording drum, to a peripheral surface of said recording drum; andrear end clamps for fixing a rear end of the recording medium mounted peripherally of said recording drum, to the peripheral surface of said recording drum, said rear end clamps being movable along recesses formed to extend circumferentially of said recording drum;said recording medium being mounted peripherally of said recording drum, with an edge of said recording medium axially of said recording drum overhanging one of said recesses;wherein a margin of the recording medium for gripping by said rear end clamps is changeable according to one of rigidity of the recording medium mounted peripherally of said recording drum and a length of the recording medium overhanging said one of said recesses.

2. An image recording apparatus as defined in claim 1, wherein positions of the recording medium gripped by said rear end clamps are shiftable circumferentially of said recording drum according to one of the rigidity of the recording medium mounted peripherally of said recording drum and the length of the recording medium overhanging said one of said recesses.

3. An image recording apparatus as defined in claim 2, wherein the margin is enlarged when the recording medium is highly rigid.

4. An image recording apparatus as defined in claim 2, wherein the margin is reduced when the recording medium overhanging said one of said recesses by a large length.

5. An image recording apparatus as defined in claim 2, wherein the positions of the recording medium gripped by said rear end clamps are shiftable axially of said recording drum according to one of the rigidity of the recording medium mounted peripherally of said recording drum, and the length of the recording medium overhanging said one of said recesses.

6. An image recording apparatus as defined in claim 5, wherein the positions of the recording medium gripped by said rear end clamps are shiftable in a direction of overhanging said one of said recesses when the recording medium is highly rigid.

7. An image recording apparatus as defined in claim 5, wherein the positions of the recording medium gripped by said rear end clamps are shiftable in a direction counter to a direction of overhanging said one of said recesses when the recording medium overhangs said one of said recesses by a large length.

8. An image recording apparatus as defined in claim 2, wherein an area of contact between the recording medium and said rear end clamps over said recesses is changed according to one of the rigidity of the recording medium mounted peripherally of said recording drum, and the length of the recording medium overhanging said one of said recesses.

9. An image recording apparatus as defined in claim 8, wherein the area of contact between the recording medium and said rear end clamps over said recesses is enlarged when the recording medium is highly rigid.

10. An image recording apparatus as defined in claim 8, wherein the area of contact between the recording medium and said rear end clamps over said recesses is reduced when the recording medium overhangs said one of said recesses by a large length.

11. An image recording apparatus as defined in claim 10, wherein: each of said rear end clamps has an elastic element for contacting a surface of the said recording medium;said elastic element having a pair of projections for contacting the recording medium over one of said recesses when the recording medium is gripped;said rear end clamps being arranged in positions where both of said projections contact the recording medium when the recording medium is highly rigid, and in positions where one of said projections contacts the recording medium when the recording medium is low in rigidity.

12. An image recording apparatus as defined in claim 11, wherein said pair of projections are spaced apart by a predetermined distance circumferentially of said recording drum.

13. An image recording apparatus as defined in claim 10, wherein: each of said rear end clamps has an elastic element for contacting a surface of the said recording medium;said elastic element having a pair of projections for contacting the recording medium over one of said recesses when the recording medium is gripped;said rear end clamps being arranged in positions where one of said projections contacts the recording medium when the recording medium overhangs said one of said recesses by a large length, and in positions where both of said projections contact the recording medium when the recording medium overhangs said one of said recesses by a small length.

14. An image recording apparatus as defined in claim 13, wherein said pair of projections are spaced apart by a predetermined distance circumferentially of said recording drum.