US3800933A

US3800933A - Printed and carriage control therefor

Info

Publication number: US3800933A
Application number: US00295153A
Authority: US
Inventors: T Taylor
Original assignee: International Standard Electric Corp
Current assignee: Alcatel Lucent NV
Priority date: 1971-10-14
Filing date: 1972-10-05
Publication date: 1974-04-02
Anticipated expiration: 1991-04-02
Also published as: GB1300519A; DE2249855A1; NL7213923A; IT968827B; SE382734B; FR2157390A5

Abstract

A teleprinter or the like wherein a typewheel is rotated around a helically grooved rod. The typewheel has an internal projection to ride in the groove. The rod is rotated at different speeds for carriage advance, stop and return. The typewheel is rotated continuously.

Description

United States Patent [191 Taylor 1 1 Apr. 2, 1974 PRINTED AND CARRIAGE CONTROL [561 References Cited THEREFOR UNITED STATES PATENTS lnventori Terence Francis Edward Taylor, 2,774,8l6 l2/l956 Yost 197 49 x Burgess Hill, England 3,630,335 12 1971 Chamncss 197 49 [73] Assignee: International Standard Electric Corp New York, NY Primary Examiner-Robert E. Pulfrey Assistant ExaminerR. T. Rader [22] Ffled' 1972 Attorney, Agent, or FirmC. Cornell Remsen, Jr. [21] Appl. No.: 295,153

' V [57] ABSTRACT [30] Foreign Application Priority t A teleprinter or the like wherein a typewheel is re- Oct. 14, 1971 Great Britain 47836/71 tated around a helically grooved rod. The typewheel has an internal projection to ride in the groove. The [52] U.S. Cl. 197/49, 74/27 rod is rotated at different speeds for carriage advance, [51] InLCl B4lj 1/32 stop and return, The typewheel is rotated continul ously.

Field of Search 197/49, 1, 18, 50;

2 Claims, 3 Drawing Figures I PRINTED AND CARRIAGE CONTROL THEREFOR BACKGROUND OF THE INVENTION This invention relates to the printing art, and more particularly, to a teleprinter or the like and a carriage control therefor.

In the past it has been difficult and expensive to maintain teleprinters.

SUMMARY OF THE INVENTION BRIEF DESCRIPTION OF THE DRAWINGS In the drawings which are to be regarded as merely illustrative:

FIG. 1 is a top plan veiw of a traversing drive constructed in accordance with the present invention; and

FIGS. 2 and 3 are enlarged views, partly in section, of the traversing drive shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT sary, and a typewheel drive pinion Pinion 5' is fixed relative to typewheel 1 and meshes with pinion 4'. The typewheel drive pinion 5 is supported on a rotatable cylindrical rod 6' having a helical groove 7 cut into its surface. A tooth in the bore of the typewheel drive pinion 5 (not visible in the figure) engages in the groove, so that when there is relative rotary motion between typewheel drive pinion 5 and rod 6, the typewheel drive pinion 5 travels along the rod like a nut on a bolt.

The rod 6, mounted in bearings in the frame of the printer, is fixed relative to one part ofa clutch 8' at one end and with one part of a clutch 9 and a brake 10 at the other end. The other part of clutch 8 is fixed relative to a drive which rotates at a speed faster than, and in the same direction as, the typewheel drive pinion 5, and the other part of clutch 9 is fixed relative to a drive which rotates at the same speed and in the same direction of the typewheel drive pinion 5'.

The driving arrangement operates in the manner described below.

When no feed of the typewheel l is required in either direction, the clutch 9' is engaged and the rod 6' rotates with the typewheel drive pinion 5'. There is,

2 thus, no relative rotary motion between the rod 6' and the typewheel drive pinion 5 and, therefore, no traversing motion. This may be visualized as a bolt with a nut on it held still; the nut does not travel along the bolt. When the typewheel l is to be fed forward, that is in the direction of printing letters sequentially, clutch 9' is disengaged and clutch 8' is engaged. The rod 6 then rotates faster than the typewheel drive pinion 5' and the hand of the helical groove is such that the typewheel l feeds forward to a new position whereupon clutch 8' is disengaged and clutch 9 reengaged. The feeding motion may be visualized by the bolt with a nut on it being turned in the unscrewing direction, the bolt not moving sideways and the nut being prevented from rotating; the nut travels along the bolt in the screwing-off direction.

When carriage return is required, that is, the typewheel 1 must be fed to the beginning of a printing line,

both clutches are disengaged and the brake 10' is applied. The typewheel drive pinion 5 now revolves rapidly with respect to the rod 6, and travels rapidly along the rod 6' to the beginning of a line of print. This motion may be visualized by the bolt with a nut on it being held-stationary while the nut is revolved rapidly in the direction to screw it on to the bolt.

To give some idea of the relative motions of the typewheel 1 and rod6, consider the typewheel drive pinion revolving at a speed of 1,200 revolutions per minute, clutch 9' being driven at the same speed, clutch 8 being driven at 1,236 revolutions per minute and the helical groove having four turns along the length of the rod 6'. Then during forward feed, the typewheel 1 moves forward one character pitch for each complete revolution of the drive pinion, and during carriage return, the typewheel l returns from the end of a line to the beginning in four complete revolutions of the drive pinion 5' which correspond to the time taken to print four characters. The dimensions of rod 6, typewheel l and typewheel drive pinion 5 are, of course, chosen to suit a particular speed of printing.

To prevent damage to the typewheel pinion 5 and rod 6, the helical groove is provided with a run-out at the line-start end so that the drive pinion can revolve harmlessly without further sideways motion. Normally the clutching and braking operations arrest the traverse motion before the wheel reaches the run-out portion. A similar run-out is provided at the other end as a further safeguard although the typewheel 1' never approaches that end at a high traverse rate.

On-the-fly printing requires a hammer carriage which feeds in synchronism .with the typewheel. A simple method of doing this is shown here where the hammer carriage llis linked to the typewheel assembly by virtually inextensible cards 12 passing around pulleys 13' in the manner shown.

With a typewheel perpendicular to the one described hereinabove, obviously, it is the typewheel drive pinion only which can rotate around the rod, rather than the typewheel itself.

In FIG. 1, gear 2 may be press fit or integral with a shaft 15 that is rotatably mounted through a frame stringer 16'. Shaft 15' is rotated by a motor 14'. A pinion 18 in mesh with gear 2 may have a shaft 19 integral therewith or press fit thereinto and press fit into the left end of pinion 3'. Shaft 19 is rotatable through stringer 16' as shown in FIG. 1. The carriage is illustrated at 25.

A fitting 22 is shown in FIG. 1 which has a head 23 and a shaft 24 which may -be integral therewith or press fit thereinto or therethrough. Shaft 24' is press fit into the right end of pinion 3, but is rotatable through a frame stringer l7.-

Carriage 25' has a projection 21 into which a shaft 20 is press fit, as shown in FIGS. 1 and 3.

In FIG. 2, the manner in which shaft 'is rotatable through stringer 16' is illustrated. Shaft 15 has

grooves

26 and 27 into which snap rings 28 and 29, respectively, are fitted.

In FIG. 3, pinion 4 is maintained in a fixed axial position on and rotatably around stub shaft For this purpose, stub shaft 20 has a snap ring groove 30, and a snap ring 31 therein. The

numbers

2, 3 and 4 indicated by an arrow 32 in FIG. 3 are the

same numbers

2, 3 and 4 indicated by an arrow 32" in FIG. 1.

What is claimed is:

1. A printing mechanism comprising: a frame; a rod rotatably mounted on said frame parallel to a printing line, said rod having a cylindrical outer surface with a helical groove therein; a typewheel rotatable on said rod, said typewheel having a projection extending into said groove; first means mounted on said frame to cooperate with means mounted on said typewheel to rotat e said typewheel in a predetermined direction continously at a constant speed relative to said frame; second means mounted on said frame, said second means being selectively operable to rotate said rod in said predetermined direction at 'an angular velocity greater than that of said typewheel; third means mounted on said frame, said third means being selectively operable to rotate said rod in said predetermined direction at an angular velocity equal to that of said typewheel whereby, when said third means is operable, no movement of the typewheel along the rod occurs while when the second means is operable the typewheel feeds to a new position; fourth means mounted on said frame, said fourth means being selectively operable to brake said rod thereby causing said typewheel to be fed to the beginning of a new print line by said first means, said typewheel having type fonts mounted thereon therearound; and fifth means mounted on said frame, said fifth means being selectively operable to cause any one vof said type fonts to make an impression on a recording medium.

2. The invention as defined in claim 1, wherein said first means includes a first pinion fixed to said typewheel, said rod and said first pinion having the same rotational axis, a carriage slidable over said rod in a fixed angular position therearound relative to said frame, said typewheel being rotatable relative to said carriage but always movable therewith in the direction of said axis, a second pinion rotatably mounted on said carriage in mesh with said first pinion, a third pinion rotatably mounted on said frame in mesh with said second pinion, said first and second pinions having thicknesses at leastan order of magnitude less than the thickness of said third pinion.

Claims

1. A printing mechanism comprising: a frame; a rod rotatably mounted on said frame parallel to a printing line, said rod having a cylindrical outer surface with a helical groove therein; a typewheel rotatable on said rod, said typewheel having a projection extending into said groove; first means mounted on said frame to cooperate with means mounted on said typewheel to rotate said typewheel in a predetermined direction continously at a constant speed relative to said frame; second means mounted on said frame, said second means being selectively operable to rotate said rod in said predetermined direction at an angular velocity greater than that of said typewheel; third means mounted on said frame, said third means being selectively operable to rotate said rod in said predetermined direction at an angular velocity equal to that of said typewheel whereby, when said third means is operable, no movement of the typewheel along the rod occurs while when the second means is operable the typewheel feeds to a new position; fourth means mounted on said frame, said fourth means being selectively operable to brake said rod thereby causing said typewheel to be fed to the beginning of a new print line by said first means, said typewheel having type fonts mounted thereon therearound; and fifth means mounted on said frame, said fifth means being selectively operable to cause any one of said type fonts to make an impression on a recording medium.

2. The invention as defined in claim 1, wherein said first means includes a first pinion fixed to said typewheel, said rod and said first pinion having the same rotational axis, a carriage slidable over said rod in a fixed angular position therearound relative to said frame, said typewheel being rotatable relative to said carriage but always movable therewith in the direction of said axis, a second pinion rotatably mounted on said carriage in mesh with said first pinion, a third pinion rotatably mounted on said frame in mesh with said second pinion, said first and second pinions having thicknesses at least an order of magnitude less than the thickness of said third pinion.