Device and method for controlling sheet feed in a printer

Claim 2

A sheet feed control device for use in a printer of the kind including a feeding means for moving a print sheet along a feed path, a printing means disposed alongside a print position on said feed path and a cutting means for cutting said print sheet and disposed alongside a cutting position in said feed path downstream of the print position with respect to the sheet feeding direction, said device comprising: a reference position indicator disposed alongside a reference position in said feed path upstream of said print position with which a predetermined print position on said print sheet may be aligned; a detection means disposed at a detection position alongside the feed path upstream of the print position for detecting the presence or otherwise of said print sheet and producing a sheet presence signal; a measuring means responsive to said sheet presence signal for measuring a distance (L4) between said detection position and the position of said leading edge of said print sheet where said predetermined print position is aligned with said reference position and outputting a distance signal; and a control means for controlling said feeding means in accordance with the measured distance so that the print sheet may be fed to a desired cutting position.

Claim 3

A sheet feed control device according to claim 1, wherein said control means further controls said feeding means in accordance with the distance (L2) between the print position and the detection position, and the distance (L3) between said print position and said cutting position.

Claim 4

A sheet feed control device according to claim 1 or 2, wherein said control means comprises a first control means for controlling said feeding means to move said print sheet to a position where said predetermined print position is in coincidence with said print position and a second control means for controlling said feeding means to move said print sheet to a position where said leading edge of said print sheet projects over said cutting position by a predetermined length.

Claim 5

The device as claimed in claim 3, wherein said print sheet is in a continuous form connecting a plural number of segmental sheets in succession at a boundary line, each of said segmental sheets having said predetermined length.

Claim 6

The device as claimed in claim 1, 2, 3 or 4, wherein said detection position is downstream of said reference position with respect to said feeding direction.

Claim 7

The device as claimed in claim 1, 2, 3 or 4, wherein said detection position is upstream of said reference position with respect to said feeding direction.

Claim 9

The device as claimed in claim 4, wherein said second control means controls said feeding means to move said print sheet to a position where said boundary line is in coincidence with said cutting position.

Claim 11

The device as claimed in claim 2, wherein said control means controls said feeding means in accordance with the further distance L1 between said print position and said reference position.

Claim 14

In a printer of the kind including a feeding means for moving a print sheet along a feed path, said print sheet having a leading edge and being in a continuous form connecting a plural number of segmental sheets in succession at a boundary line, each segmental sheet having a predetermined length, and wherein printing is carried out from a preselected line in each of said segmental sheets, and said feed path having first, second, third and fourth positions, said second position being downstream of said first position and said third and fourth positions being upstream of said first position, a printing means disposed alongside of said first position for carrying out printing on said print sheet, a cutting means disposed alongside of said second position for cutting said print sheet in every segmental sheet, and a control means for controlling said feeding means, a feed control method of said print sheet comprising the steps of: (a) manually moving said preselected line of a first segmental sheet of said print sheet to said third position; (b) measuring a distance L4 between said fourth position and said leading edge; (c) moving said print sheet to said first position; and (d) moving said print sheet in accordance with said distance L4 being measured in step (b) until said boundary line is in coincidence with said second position.

Claim 15

In a printer of the kind including a feeding means for moving a print sheet along a feed path, said print sheet having a leading edge and being in a continuous form connecting a plural number of segmental sheets in succession at a boundary line, each segmental sheet having a predetermined length, and wherein printing is carried out from a preselected line in each of said segmental sheets, and said feed path having first, second, third and fourth positions, said second position being downstream of said first position and said third and fourth positions being upstream of said first position, a printing means disposed alongside of said first position for carrying out printing on said print sheet, a cutting means disposed alongside of said second position for cutting said print sheet in every segmental sheet, and a control means for controlling said feeding means, a feed control method of said print sheet comprising the steps of: (a) manually moving said preselected line of a first segmental sheet of said print sheet to said third position; (b) measuring a distance L4 between said fourth position and said leading edge; (c) moving said print sheet to said first position; and (d) moving said print sheet in accordance with said distance L4 being measured in step (b) until said boundary line is in coincidence with said second position.

Claim 16

The method as claimed in claim 13, wherein in step (c), said print sheet is moved until said preselected line is brought to be in coincidence with said first position and if further moved in accordance with the printing operation by said printing means.

Claim 17

The method as claimed in claim 14, wherein said step (c) further comprises moving said print sheet from a position where a preceding segmental sheet is placed in said first position to a position where said preselected line of the subsequent segmental sheet is in coincidence with said first position.

Claim 18

The method as claimed in claim 15, wherein said third position is downstream of said fourth position with respect to said feeding direction, and wherein in said step (d), when said print sheet is in a position where said preselected line is in said first position, said print sheet is moved by a distance X represented by an equation X = L3 - L4 + L2 -L1, where L3 is a distance between said first position and said second position and L2 is a distance between said first position and said fourth position.

Claim 19

The method as claimed in claim 16, wherein said control means includes a storage means for storing data on said distances L1, L2, L3 and L4, and a computing means for computing said distance X in accordance with said equation and outputting a data on said distance X to said feeding means to move, in said step (e), said print sheet by said distance X.

Claim 20

The method as claimed in claim 14, 15, 16 or 17, wherein a leading edge detecting means is disposed alongside of said fourth position for detecting said leading edge, and wherein in said step (b), from a position where said print sheet has been moved in step (a), said print sheet is backwardly moved until said leading edge is detected by said leading edge detecting means to thus measure said L4, and then said print sheet is forwardly moved by a sum of said distances L4 and L1.

Claim 21

The method as claimed in claim 15, 16 or 17, wherein said third position is downstream of said fourth position with respect to said feeding direction, and wherein in said step (d), when said print sheet is in a position such that a printed segmental sheet is in said first postion said print sheet is moved by a distance Z represented by an equation Z = L - (A + L4 - L2 + L1) + L3, where L is said predetermined length, A is a number of line changes attendant to said printing, L1 is a distance between said first position and said third position, L2 is a distance between said first position and said fourth position, and L3 is a distance between said first position and said second position.

Claim 22

The method as claimed in claim 15, wherein said third position is upstream of said fourth position with respect to said feeding direction, and wherein in said step (d), when said print sheet is in a position such that said preselected print position is in said first position, said print sheet is moved by a distance W represented by an equation W = L3 - (L1 - L4 - L5), where L1 is a distance between said first position and said third position, L3 is a distance between said first position and said second position, and L5 is a distance between said first position and said fourth position.