US2909602A

US2909602A - Line feed for page printer

Info

Publication number: US2909602A
Application number: US574520A
Authority: US
Inventors: Walter J Zenner
Original assignee: Teletype Corp
Current assignee: AT&T Teletype Corp
Priority date: 1956-03-28
Filing date: 1956-03-28
Publication date: 1959-10-20
Anticipated expiration: 1976-10-20

Description

Oct. 20, 1959 W. J. ZENNER LINE FEED FOR PAGE PRINTER Filed March 28, 1956 FIG. 3

INVENTOR WALTER J. ZENNER BYE 4407 l ATTORNEY United States Patent LINE FEED FOR PAGE PRINTER Walter J. Zenner, Des Plaines, Ill., assign'or to Teletype Corporation, Chicago, Ill., a corporation of Delaware Application March 28, 1956, Serial No. 574,520

7 Claims. '(Cl. 178-25) This invention pertains to printing telegraph apparatus and more particularly to printing telegraph page printers. The principal object of this invention is to provide a page printer with a record advancing device which is powered and operated independently of the operating motor of the apparatus.

Another object is to provide one mechanism which will serve both as a line feed device and a feed-out device without the necessity of engaging or disengaging different feeding mechanisms.

l Yet another object is to provide a feed-out mechanism which operates at a very high speed. According to the present invention there is provided. a

' small, high speed electric motor having very low inertia for advancing the platen. The motor iscontrolled through a control circuit which includes an electromagnet. A program wheel is provided to be driven by the platen and cooperate with a line feed pawl to actuate the motor, or the control circuit. An armature means is associated with the electromagnet and the line feed pawl to disengage the line feed pawl from the program wheel upon the energization of the armature.

the motor 11. A contact 35 is positioned to be closed by the actuation of the armature 34 to establish a holding circuit from the source of energy 44 to the electromagnet 36.

Referring now to Fig. 1, which depicts the present invention in its normal printing position with the line feed pawl 21 being urged to the left by the ratchet 18 to hold the transfer contact 26 in engagement with the control circuit so that the circuit is conditioned for energizing the magnet 36 upon the closing of the line feed contact 38. When the line feed signal is received inthe printer,

the code bars 39 are so aligned as to allow the line feed 36 to negative battery to energize the electromagnet 36.

Energization of the magnet 36 causes the armature 34 and the armature extension 33 to be moved upward, which movement causes the lifting interponent 28 to be rotated counterclockwise about its pivot and move the tip 23 of the line feed pawl 21 out of engagement with the ratchet, thereby allowing the line feed pawl 21 to be moved to the right by its spring 48. The spring contact 26, being normally biased toward the contact 25, is permitted to be engaged with the contact 25, by the movement of the line feed pawl 21, to energize the motor 11 from the source of energy 27 to thereby advance the platen. It is apparent from the foregoing description that the energization of the magnet 36 is only momentary, since the reaction of the armature causes the contact 26 to move away from the control circuit to the motor cirg A more complete understanding of the invention may the belt or chain 13 and the wheel 14. The platen 12 has means associated with it such as the

gears

16 and 17 for driving the ratchet or program wheel 18 as it is advanced by the motor 11. A check pawl 19 is urged against the ratchet to prevent any clockwise rotation thereof. A

line feed pawl 21 is slidably mounted on a pin 22 suitably L positioned in the frame. The pointed extremity 23 of the pawl 21 is normally engaged with the ratchet 18 while the butt end 24 is in contact with the transfer contact 26 which is connected with the source of energy 27. A dis- I engaging lever 28 is positioned with its lower extension 29' positioned beneath the line feed pawl and its upper extension 31 associated with the shoulder 32 of the armature extension 33. The armature extension 33 is fastened to the armature 34 which is positioned to be attracted by the energization of the electromagnet 36.

A line feed lever 37 is in camming relationship with the line feed contact 38 so that when the code bars 39 are aligned to select lever 37 in the manner well known in the art, the contact 38 is closed to apply energy to the magnet 36 from the energy source 27. The feed-out lever 41 is similarly associated with the feed-out contact 42. Closing of the feed-out contact applies positive battery to theslow release relay 43. Energization of the relay 43 establishes a circuit from 'a source of energy 44 cuit. As soon as the magnet 36 is energized it will close contact 35, but magnet 36 will not be locked operated because contact 26 will move away from contact 20 and contact 35 will open before contact 26 engages contact 25 When positive battery is removed from the magnet 36, the armature 34 and its extension 33 return to their unoperated position so that the pawl 21 is allowed to engage the ratchet 18 at a position, governed by the length of the slot in the pawl 21, from which it will require a predetermined movement of the platen 12 and thereby the ratchet 18 to move the pawl 21 to the left to move the con tact leaf 26 from the contact 25 to contact 20. Movement of the contact leaf 26 from the contact 25' will stop the motor 11 and condition the control circuit for future operation. It is, of course, understood that the rotation of the line feed lever 37 is of relatively short duration so that contact 38 is open before the pawl 21 is moved to the left by the rotation of the platen 12.

The line feed contact 38 and the feed-out contact 42 are arranged in any suitable manner such as that shown in Fig. 3 so that while the line feed contact 38 may be closed independent of the feed-out contact 42, closing of contact 42 will simultaneously close the line-feed contact 38.

. When the feed-out signal is received in the printer, the feed-out lever 41 is moved clockwise in the usual manner of selection to close the contacts 42and 38. Closing of the contact 38 energizes the electromagnet 36 and disengages the line'feed pawl 21 from the ratchet 18 as set forth above. Momentary closing of the contact 42 causes the delay relay 43 to be energized thus completing'a temporary holding circuit from positive battery 44 through the contact 35 and the magnet 36. The slow release relay 43 holds the make contact 46 operated during the time required to move the contact 26 from point 20, of the control circuit to point 25 of the motor circuit. When the transfer is completed, the relay 43 releases and the magnet 36 gets locking battery from the energy s ource 27 through the conductor 47 and the contact 35. Since the magnet is held energized, the line feed pawl is held out of engagement with the ratchet 18 so the platen is continuously advanced by the motor. A projection or lug 49 is placed at a predetermined point on the ratchet so that when the 'platen '12 and thereby the ratchet 18 has been advanced to a predetermined point, the lug 49 will engage the armature extension 33 and cause it to be rotated in a clockwise direction (Fig. 1). Rotation of the extension 33 moves the shoulder 32 out of contact with the projection 31 of the lifting lever 28 to allow the lever 28 to be rotated clockwise so that the pawl 21 is once more engaged with the ratchet 18. The ratchet 18 moves the pawl 21 as set forth above to shut olf the motor after a predetermined amount of platen advance.

While a preferred form of the invention has been disclosed and described herein, it is obvious that changes may be made in the details without departing from the spirit or scope of this invention.

What is claimed is:'

1. In a telegraph printer, a rotatable platen, a platen driving motor for imparting rotation to said platen, an electromagnetically controlled line feed mechanism for controlling said motor comprising an escapement facility, a first selectable means elfective when selected to cause said mechanism to effect the rotation of said platen a predetermined invariable amount, and a second selectable means cooperating with said first selectable means and effective when selected to cause said mechanism to effect the rotation of said platen variable amounts.

2. In a device for advancing a record through a telegraph printer in incremental steps, a rotatable platen, a motor for rotating said platen, a power source, a transfer contact biased to connect said power source to said motor to energize said motor, a normally open control circuit including an electromagnet, means actuated by the rotation of said platen for moving said transfer contact to break the connection between the motor and power source and to make a connection between said power source and said control circuit, an armature actuated by said electromagnet for rendering said contact moving means effective, and means selectively actuated by the printer to close said control circuit.

3. In a telegraph printer, a record advancing means comprising a rotatable platen, a power source, an electric motor for rotating said platen, a control circuit including an electromagnet, selectively actuated means in said printer for closing said control circuit to energize said electromagnet, means actuated by said electromagnet when said electromagnet is energized for supplying power from said source to said motor, said last mentioned means including an element movable to open the circuit from the power source to said motor when the magnet is deenergized, means actuated by the rotation of said platen for moving said element to position to open said motor circuit, and means actuated by the energization of said magnet for causing said element to de-energize the control circuit.

4. In a telegraph printer having a rotatable platen and a program wheel adapted to be rotated by the rotation of said platen, a form feed-out mechanism comprising a motor for rotating said platen, a power source, switch means biased to connect the power source to said motor, a control circuit, switch control means normally engaged by said program wheel for holding said switch means in position to connect the power source to the control circuit and to disconnect the power source from the motor, an electromagnet in said control circuit, an armature actuated by said magnet for disengaging said switch control means from said program wheel, signal controlled means selectively actuated by the printer for closing said control circuit to energize said magnet for a predetermined length of time, a holding circuit for holding said magnet energized to maintain the circuit from the power source to the motor closed, means controlled by the rotation of the platen to a predetermined point for rendering said holding circuit ineffective, and a signal controlled means for energizing said holding circuit.

5. In a telegraph recorder having a rotatable platen and a program wheel driven thereby, a circuit including a motor for rotating said platen, a power circuit having a transfer contact therein which is biased to connect power to said motor, a first normally open control circuit which includes an electromagnet, escapement means for engagement with said program wheel to move said transfer contact to open the power circuit to said motor and to close the power circuit to said control circuit, armature means actuated by said magnet to move said escapement means out of engagement with said program wheel, whereby said transfer contact is allowed to close the power circuit to said motor, a second normally open control circuit for supplying power to said motor, means actuated by the operation of said magnet for connecting said second control circuit to'said magnet, signal selected means for simultaneously closing said first and second control circuits, and means actuated by the advance of said program wheel to a predetermined point for nullifying the effect of said armature means on said escapement means.

6. Apparatus for advancing a record through a telegraph printer comprising a motor, a platen arranged to be driven by said motor, a power source, a first normally open contact arranged to be selected and closed by said printer, an electromagnet connected to be supplied with energizing power upon the closure of said first contact, a transfer contact connected to said power source and normally positioned to supply power from said source to said first contact, a second contact associated with said transfer contact and connected to said motor, said transfer contact being biased to disconnect power at said source from said first contact and to connect it to said second contact, a pawl normally restraining said platen against rotation and arranged to be driven to a position to move said transfer contact to normal position when the motor drives the platen, and means actuated by said electromagnet for tripping said pawl out of restraining relation with the platen thereby to energize said motor.

7. Apparatus for advancing a record through a telegraph printer comprising a motor, a platen arranged to be driven by said motor, a power source, a first normally open contact arranged to be selected and closed by said printer, an electromagnet connected to be supplied with energizing power upon the closure of said first contact, a transfer contact connected to said power source and normally positioned to supply power from said source to said first contact, a second contact associated with said transfer contact and connected to said motor, said transfer contact being biased to disconnect power at said source from said first contact and to connect it to said second contact, a pawl arranged to be driven to a position to move said transfer contact to normal position when the motor drives the platen, means actuated by said electromagnet for tripping said pawl out of restraining relation with the platen thereby to energize said motor, a third normally open contact arranged to be selected and closed by the printer, means actuated by the closure of said third contact for supplying power to said motor,

and means actuated by said last-mentioned means forv holding said electromagnet operated for a predetermined interval of time.

References Cited in the file of this patent 2 UNITED STATES PATENTS 2,160,139 .Haglund et al May 30, 1939 2,330,250 Sylvester Sept. 28, 1943 2,536,528 Baldwin Jan. 2, 1951 2,672,508 Lang Mar. 16, 1954