Printing apparatus

Claim 2

In apparatus for printing characters from a multi-position printing head, the improvement comprising in combination: means for providing pulsed motive power subject to terminal fluctuation; means advancing said printing head with said pulsed motive power to any printing position, said advancing means include means for yieldably coupling said motive power means to said printing head; means coupled to said printing head for releasably retaining said printing head in any printing position whereby said yieldable coupling means absorb said motive power terminal fluctuation; and means including printing hammer means separate from said releasable retaining means for printing characters from said printing head.

Claim 3

An apparatus as claimed in claim 1, wherein: said printing head is a rotary printing head having a plurality of angular printing positions; said motive power providing means include means for providing pulsed rotary motive power subject to angular terminal fluctuation; said advancing means include means for yieldably coupling said pulsed rotary motive power means to said rotary printing head to step the printing head to any angular printing position; said retaining means include means coupled to said rotary printing head for releasably retaining said rotary printing head in any angular printing position whereby the yieldable coupling means absorb said angular terminal fluctuation; and said printing means include printing hammer means separate from said releasable retaining means for printing characters from said rotary printing head.

Claim 4

An apparatus as claimed in claim 2, wherein: said yieldable coupling means include resilient means for coupling said motive power to said printing head.

Claim 5

An apparatus as claimed in claim 2, wherein: said yieldable coupling means include spring means extending essentially parallel to the axis of rotation of said rotary printing head, means for connecting a first end of said spring means to said motive power providing means, and means for connecting a second end of said spring means to said rotary printing head.

Claim 6

An apparatus as claimed in claim 4, wherein: said yieldable coupling means include means for limiting lateral deflection of said spring means relative to said axis of rotation.

Claim 7

An apparatus as claimed in claim 2, wherein: said releasable retaining means include resilient detent means coupled to said printing head.

Claim 8

An apparatus as claimed in claim 1, wherein: said yieldable coupling means include resilient means for coupling said motive power to said printing head.

Claim 9

An apparatus as claimed in claim 1, wherein: said yieldable coupling means include spring means, means for connecting a first end of said spring means to said motive power providing means, and means for connecting a second end of said spring means to said printing head.

Claim 10

An apparatus as claimed in claim 8, wherein: said yieldable coupling means include means for limiting deflection of said spring means.

Claim 11

An apparatus as claimed in claim 1, wherein: said releasable retaining means include resilient detent means coupled to said printing head.

Claim 12

In apparatus for printing characters, the improvement including in combination: a rotary character printing head having a plurality of angular printing positions; means including a stepping motor having a motor shaft for providing about an axis of rotation pulsed rotary motive power for stepping said printing head, said pulsed rotary motive power being subject to terminal fluctuation; means for yieldably coupling said printing heAd to said stepping motor shaft; means including a spring-biased detent for releasably retaining said rotary printing head in each of said angular printing positions upon deenergiation of said stepping motor means whereby said yieldable coupling means absorb said terminal fluctuation of said rotary motive power; and means including printing hammer means separate from said printing head retaining means for printing characters from said printing head.

Claim 13

In apparatus for printing characters, the improvement including in combination: a rotary character printing head having a plurality of angular printing positions; means including a stepping motor having a motor shaft for providing about an axis of rotation pulsed rotary motive power for stepping said printing head, said pulsed rotary motive power being subject to terminal fluctuation; means for yieldably coupling said printing heAd to said stepping motor shaft; means including a spring-biased detent for releasably retaining said rotary printing head in each of said angular printing positions upon deenergiation of said stepping motor means whereby said yieldable coupling means absorb said terminal fluctuation of said rotary motive power; and means including printing hammer means separate from said printing head retaining means for printing characters from said printing head.

Claim 14

An apparatus as claimed in claim 11, wherein: said rotary printing head includes a plurality of notches corresponding to said angular printing positions; and said spring-biased detent is coupled to said notches.

Claim 15

An apparatus as claimed in claim 11, wherein: said yieldable coupling means include a buffer spring having a first leg connected to said motor shaft, a bight portion extending essentially parallel to the axis of rotation of said motor shaft, and a second leg connected to said rotary printing head.

Claim 16

An apparatus as claimed in claim 13, wherein: said rotary printing head has a collar having a lateral aperture; and said second leg of said buffer spring extends into said lateral aperture of said printing head collar.

Claim 17

An apparatus as claimed in claim 14, wherein: said rotary printing head includes an annular element connected to said collar and having a plurality of notches corresponding to said annular printing positions; and said spring-biased detent is coupled to said notches.

Claim 18

An apparatus as claimed in claim 15, wherein: said yieldable coupling means further include a coupling member connected to said motor shaft and having a slot having a width greater than the thickness of said buffer spring for receiving part of said second leg of said buffer spring.

Claim 19

An apparatus as claimed in claim 16, wherein: said coupling member has an axial slot for receiving said first leg of said buffer spring.

Claim 20

An apparatus as claimed in claim 17, wherein: said coupling member has a radial slot adjacent said axial slot for receiving a further part of said buffer spring.