Printing needle drive

Claim 2

Printing needle drive comprising supporting means; elongated lever means having a fulcrum mounted on said supporting means and being formed over the whole length thereof from resilient material; printing needle means secured to a first portion of said lever means and projecting therefrom transversely to said lever means; and electromagnetic means including a movable armature connected with a second portion of said lever means spaced from said fUlcrum a smaller distance than said first portion so that when said armature is moved in an armature stroke of predetermined length, said needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than said armature, the mass of said needle means having a predetermined magnitude to prevent movement of said first portion of said lever means during the first part of said armature stroke whereby said resilient lever means is resiliently deformed and tensioned so that said resilient lever means recoils during the second part of said armature stroke and accelerates said needle means faster than said armature is accelerated when said electromagnet means is energized.

Claim 3

Printing needle drive as claimed in claim 1 wherein said supporting means include pivot means at one end of said lever means for mounting said fulcrum of said lever means; wherein said first portion is an end portion, located at the other end of said lever means; and wherein said armature is connected with said second portion intermediate said ends.

Claim 4

Printing needle drive as claimed in claim 1 wherein said electromagnetic means includes an annular winding; wherein said armature is axially movable in said annular winding and has an armature end portion projecting from said winding and directly secured to said second portion of said lever means.

Claim 5

Printing needle drive as claimed in claim 1 wherein said lever means is a resilient steel rod having said second portion located in a bore in said armature.

Claim 6

Printing needle drive as claimed in claim 1 wherein said printing needle means includes a wire having a projecting printing end portion, and a resilient attaching end portion attached to said first portion of said lever means so that said wire is resiliently secured to said lever means.

Claim 7

Printing needle drive as claimed in claim 5 wherein said resilient attaching portion of said wire is wound to form a coil tightly surrounding said first portion of said lever means so that said printing end portion of said wire is resiliently secured to said lever means.

Claim 8

Printing needle drive as claimed in claim 2 wherein the thickness and rigidity of said wire is selected so that at least the first turn of said coil resiliently spreads and increases the diameter thereof when said projecting printing end portion abuts a printing surface at the end of said needle stroke.

Claim 9

Printing needle drive comprising support means; lever means having a fulcrum mounted on said supporting means and an end portion opposite said fulcrum; printing needle means including a wire having a printing end portion projecting transversely from said end portion of said lever means and a resilient attaching end portion forming a coil tightly surrounding said end portion of said lever means so that printing end portion is resiliently secured to said lever means; an oscillation supressing jacket consisting of synthetic material and enveloping said coil, said end portion in said coil, and a portion of said wire adjacent said coil; and electromagnetic means including a movable armature connected with a second portion of said lever means spaced from said fulcrum a smaller distance than said end portion so that when said armature is moved in an armature stroke of predetermined length, said needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than said armature.

Claim 10

Printing needle drive comprising support means; lever means having a fulcrum mounted on said supporting means and an end portion opposite said fulcrum; printing needle means including a wire having a printing end portion projecting transversely from said end portion of said lever means and a resilient attaching end portion forming a coil tightly surrounding said end portion of said lever means so that printing end portion is resiliently secured to said lever means; an oscillation supressing jacket consisting of synthetic material and enveloping said coil, said end portion in said coil, and a portion of said wire adjacent said coil; and electromagnetic means including a movable armature connected with a second portion of said lever means spaced from said fulcrum a smaller distance than said end portion so that when said armature is moved in an armature stroke of predetermined length, said needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than said armature.

Claim 11

Printing needle drive as claimed in claim 8, wherein said lever means is resilient, and including stop means on said supporting means for stopping said armature at the end of said armature stroke; and a damping member mounted on said support means adjacent said end portion of said lever means and on the side thereof opposite the side from which said printing end portion of said needle means projects, said damping member being engaged with said jacket when said lever means reverses and resiliently returns to the initial postion thereof after said needle means has perfoRmed said needle stroke.

Claim 12

Printing needle drive as claimed in claim 8 wherein said coil has an axis; wherein said wire includes an intermediate portion between said printing end portion and said coil, said printing end portion being straight and being located in an imaginary line passing through said axis of said coil, and said intermediate portion being cranked out of said line and extending tangentially to the first turn of said coil.

Claim 13

Printing needle drive comprising supporting means; resilient lever means having a fulcrum mounted on said supporting means; printing needle means secured to a first portion of said lever means and projecting therefrom transversely to said lever means; electromagnetic means including a movable armature connected with a second portion of said lever means spaced from said fulcrum a smaller distance than said first portion so that when said armature is moved in an armature stroke of predetermined length, said needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than said armature, the mass of said needle means having a predetermined magnitude to prevent movement of said first portion of said lever means during the first part of said armature stroke whereby said lever means is resiliently deformed and tensioned so that said resilient lever means recoils during the second part of said armature stroke and accelerates said lever means faster than said armature is accelerated when said electromagnet means is energized; and an elongated return spring extending in the general direction of said lever means, abutting in the region of opposite ends thereof against said supporting means, and being connected between the ends to said armature so as to be resiliently bent when said armature performs said armature stroke to thus return said armature to a rest position after deenergizing said electromagnetic means.

Claim 14

Printing needle drive comprising supporting means; resilient lever means having a fulcrum mounted on said supporting means; printing needle means secured to a first portion of said lever means and projecting therefrom transversely to said lever means; electromagnetic means including a movable armature connected with a second portion of said lever means spaced from said fulcrum a smaller distance than said first portion so that when said armature is moved in an armature stroke of predetermined length, said needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than said armature, the mass of said needle means having a predetermined magnitude to prevent movement of said first portion of said lever means during the first part of said armature stroke whereby said lever means is resiliently deformed and tensioned so that said resilient lever means recoils during the second part of said armature stroke and accelerates said lever means faster than said armature is accelerated when said electromagnet means is energized; and an elongated return spring extending in the general direction of said lever means, abutting in the region of opposite ends thereof against said supporting means, and being connected between the ends to said armature so as to be resiliently bent when said armature performs said armature stroke to thus return said armature to a rest position after deenergizing said electromagnetic means.

Claim 15

Printing needle drive as claimed in claim 11, and including adjustable stop means mounted on said supporting means and engaging said armature when the latter is returned by said return spring to said rest position.

Claim 16

Printing needle drive comprising supporting means; resilient lever means having a fulcrum mounted on said supporting means; printing needle means secured to a first portion of said lever means and projecting therefrom transversely to said lever means; and electromagnetic means including a movable armature connected with a second portion of said lever means spaced from said fulcrum a smaller distance than said first portion so that when said armature is moved in an armature stroke of predetermined length, said needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than said armature, the mass of said needle means having a predetermined magnitude to prevent movement of said first portion of said lever means during the first part of said armature stroke whereby said resilient means is resiliently deformed and tensioned so that said resilient lever means recoils during the second part of said armature stroke and accelerates said needle means faster than said armature is accelerated when said electromagnet means is energized, said supporting means including stop means for stopping said armature at the end of said armature stroke so that said recoiling resilient lever means continues to move said needle means in a free needle stroke after said stop means has stopped said armature, and said supporting means including further a damping member located adjacent said first portion on the side of said lever means remote from said needle means, and being engaged by said first portion when said lever means reverses and resiliently returns to the initial position thereof after performing said free needle stroke.

Claim 17

Printing needle drive comprising supporting means; resilient lever means having a fulcrum mounted on said supporting means; printing needle means secured to a first portion of said lever means and projecting therefrom transversely to said lever means; and electromagnetic means including a movable armature connected with a second portion of said lever means spaced from said fulcrum a smaller distance than said first portion so that when said armature is moved in an armature stroke of predetermined length, said needle means is moved in a needle stroke of proportionally greater length, and at a higher speed than said armature, the mass of said needle means having a predetermined magnitude to prevent movement of said first portion of said lever means during the first part of said armature stroke whereby said resilient means is resiliently deformed and tensioned so that said resilient lever means recoils during the second part of said armature stroke and accelerates said needle means faster than said armature is accelerated when said electromagnet means is energized, said supporting means including stop means for stopping said armature at the end of said armature stroke so that said recoiling resilient lever means continues to move said needle means in a free needle stroke after said stop means has stopped said armature, and said supporting means including further a damping member located adjacent said first portion on the side of said lever means remote from said needle means, and being engaged by said first portion when said lever means reverses and resiliently returns to the initial position thereof after performing said free needle stroke.