Sheet feeding device

Claim 2

A feeding device for a sheet, comprising: (a) a quadrilateral vibration member having a frictional surface in contact with the sheet, the member having at least a first side surface and a second side surface provided at a side surface different from the first side surface; (b) a first electromechanical energy conversion member, fixed to the first side surface of said vibration member, for producing a travelling vibration wave along a feeding direction of the sheet in said vibration member in response to an applied electrical signal, thereby causing a movement of the sheet; (c) a second electromechanical energy conversion member, fixed to the second side surface of the vibration member, for producing a rotating vibration which transverses the feeding direction of the sheet in the vibration member in response to an applied electrical signal, thereby causing a movement of the sheet; and (d) control circuit means for applying the applied electrical signal to said first electromechanical energy conversion member and for applying the applied electrical signal to said second electromechanical energy conversion member when the sheet has reached near the second electromechanical energy conversion member by the travelling vibration wave.

Claim 3

A feeding device according to claim 1, wherein said first electromechanical energy conversion member has two piezo-electric element groups to which the electrical signal is supplied.

Claim 4

A feeding device according to claim 1, wherein when the sheet has reached near the second electromechanical energy conversion member, said control circuit means applies the electrical signal to said first and second electromechanical energy conversion members.

Claim 5

A feeding device according to claim 2, wherein said control circuit means includes a member for simultaneously supplying said electrical signal to one of said two piezo-electrical element groups and the second electromechanical energy conversion member in response to the sheet having been moved to a predetermined position.

Claim 6

A feeding device according to claim 4, wherein said signal supplying member includes: an oscillator for generating the electrical signal to be supplied to one of said two piezo-electric element groups; a phase shifter for generating an electrical signal whose electrical phase is different from an output signal generated from said oscillator in response to said output signal; and a signal switching element for selectively supplying the electrical signal generated from said phase shifter as the applied electrical signal to either one of said two piezo-electric element groups or the second electrical energy conversion member.

Claim 7

A feeding device according to claim 5, further comprising: a sheet position detector for producing a change-over signal to be applied to the signal switching element when the sheet has reached near said second electromechanical energy conversion member.

Claim 8

A feeding device according to claim 6, wherein said second electromechanical energy conversion member includes a piezo-electric element.

Claim 9

A feeding device system comprising: (a) a sheet to be fed; (b) a vibration member, a part of which is formed arcuately, said member having a frictional surface in contact with sheet and having at least a first side surface and a second side surface provided at a side surface different from said first side surface; (c) a first electromechanical energy conversion member, provided at said first side surface of said vibration member, for producing a travelling vibration wave in said vibration member in response to an applied first electrical signal, thereby causing a relative movement between said sheet and said vibration member; (d) a second electromechanical energy conversion member, provided at said second side surface of said vibration member, for producing a rotating vibration in the vibration member in response to an applied second electrical signal, thereby causing a relative movement between said sheet and said vibration member, in which a vibrating direction of the rotating vibration is different from a vibrating direction of the travelling vibration wave by a predetermined angle; and (e) control circuit means for applying the first electrical signal to said first electromechanical energy conversion member and for applying the second electrical signal to said second electromechanical energy conversion member when said sheet has been fed to a predetermined position by the travelling vibration wave.

Claim 10

A feeding device system comprising: (a) a sheet to be fed; (b) a vibration member, a part of which is formed arcuately, said member having a frictional surface in contact with sheet and having at least a first side surface and a second side surface provided at a side surface different from said first side surface; (c) a first electromechanical energy conversion member, provided at said first side surface of said vibration member, for producing a travelling vibration wave in said vibration member in response to an applied first electrical signal, thereby causing a relative movement between said sheet and said vibration member; (d) a second electromechanical energy conversion member, provided at said second side surface of said vibration member, for producing a rotating vibration in the vibration member in response to an applied second electrical signal, thereby causing a relative movement between said sheet and said vibration member, in which a vibrating direction of the rotating vibration is different from a vibrating direction of the travelling vibration wave by a predetermined angle; and (e) control circuit means for applying the first electrical signal to said first electromechanical energy conversion member and for applying the second electrical signal to said second electromechanical energy conversion member when said sheet has been fed to a predetermined position by the travelling vibration wave.

Claim 11

A feeding system comprising: (a) a sheet; (b) a vibration having a friction surface in contact with said sheet, said vibrator having a first friction portion in contact with said sheet and a second friction portion provided in a direction transverse to said first friction portion, said vibrator also having a first electromechanical energy conversion element provided on said first friction portion so as to generate a travelling vibration wave in said vibrator in response to an applied first electrical signal and a second electromechanical energy conversion element provided in said second friction portion so as to generate a rotating vibration in said vibrator in response to an applied second electrical signal, and the travelling vibration wave and the rotating vibration causing a relative movement between said sheet and said vibrator; and (c) control circuit means for applying the first electrical signal to said first electromechanical energy conversion member and for applying the second electrical signal to said second electromechanical energy conversion element when said sheet and said vibrator are spaced away from each other by a predetermined amount by the travelling vibration wave.

Claim 12

A feeding system comprising: (a) a sheet; (b) a vibration having a friction surface in contact with said sheet, said vibrator having a first friction portion in contact with said sheet and a second friction portion provided in a direction transverse to said first friction portion, said vibrator also having a first electromechanical energy conversion element provided on said first friction portion so as to generate a travelling vibration wave in said vibrator in response to an applied first electrical signal and a second electromechanical energy conversion element provided in said second friction portion so as to generate a rotating vibration in said vibrator in response to an applied second electrical signal, and the travelling vibration wave and the rotating vibration causing a relative movement between said sheet and said vibrator; and (c) control circuit means for applying the first electrical signal to said first electromechanical energy conversion member and for applying the second electrical signal to said second electromechanical energy conversion element when said sheet and said vibrator are spaced away from each other by a predetermined amount by the travelling vibration wave.

Claim 15

A feeding device for a sheet, said device comprising: (a) a vibrator having a friction surface in contact with the sheet, said vibrator having a first friction portion in contact with the sheet and a second friction portion provided in a direction transverse to said first friction portion, said vibrator also having a first electromechanical energy conversion element provided on said first friction portion so as to generate a travelling vibration wave in said vibrator in response to an applied first electrical signal and a second electromechanical energy conversion element provided in said second friction portion so as to generate a rotating vibration in said vibrator in response to an applied second electrical signal, and the travelling vibration wave and the rotating vibration causing a relative movement between the sheet and the vibrator; and (b) said control circuit member for energizing said second electromechanical energy conversion element so that said second electromechanical energy conversion element generates the rotating vibration when the sheet and said vibrator are spaced away from each other by a predetermined amount by the travelling vibration wave.

Claim 16

A feeding device for a sheet, said device comprising: (a) a vibrator having a friction surface in contact with the sheet, said vibrator having a first friction portion in contact with the sheet and a second friction portion provided in a direction transverse to said first friction portion, said vibrator also having a first electromechanical energy conversion element provided on said first friction portion so as to generate a travelling vibration wave in said vibrator in response to an applied first electrical signal and a second electromechanical energy conversion element provided in said second friction portion so as to generate a rotating vibration in said vibrator in response to an applied second electrical signal, and the travelling vibration wave and the rotating vibration causing a relative movement between the sheet and the vibrator; and (b) said control circuit member for energizing said second electromechanical energy conversion element so that said second electromechanical energy conversion element generates the rotating vibration when the sheet and said vibrator are spaced away from each other by a predetermined amount by the travelling vibration wave.

Claim 19

A system according to claim 12, wherein said supporting member includes a base plate for a printer.