US1604851A - Silent typewriter - Google Patents

Description

Oct. 26 1926.

SILENT TYPEWRITER Filed April 18 1923 Patented Oct. 26, 1926.

PATENT OFFICE.

SCOTT H. PERRY, OF SUMMIT, NEW JERSEY.

SILENT TYPEWRITER.

Application filed April 18, 1923. Serial No. 632,856.

My invention relates to silent typewriters.

Among the objects of my invention are To produce a silent typewriter capable of the same rapidity of operation as the ordinary forms of typewriters.

To produce a silent typewriter so constructed and arranged that the type bars will be pressed against the ribbon with sufficient pressure to produce even printing without the production of noise.

To produce a silent typewriter in which the type bars shall be so operated with reference to the platen that an even pressure is produced throughout the whole of a character, whereby I avoid shaded characters in the typewritten work.

To produce a silent typewriter having a light, responsive and elastic touch.

To produce a silent typewriter having the standard keyboard consisting of four rows of keys.

To produce a silent typewriter having the type bars each provided with but two characters and so constructed and arranged that they may be assembled in several rows. By this means I am enabled to place the requisite number of characters in a relatively small space and greatly simplify the connections from the type bars to the keys.

To produce a silent typewriter having a type bar which can be moved into the operative position with reference to the platen and can then be pressed with a considerable force upon the ribbon by a suitable pressure bar having a very small range of movement.

These and further objects of my invention will be adverted to in the following specification, reference being had to the accompanying drawings, in which Figure 1 shows a section of a typewriter constructed according to my invention.

Fig. 2 is a section along the line 2-2 in Fig. 1 looking in the direction of the arrows.

Fig. 3 is a section along the line 33 in Fig. 1 looking in the direction of the arrows.

Fig. 4: is an enlarged section along the line 44 in Fig. 1 looking in the direction of the arrows.

My improved typewriter comprises broadly a key board which is preferably arranged in four banks according to the usual standard. The keys perform two functions during their depression. During the first part of their downward movement they advance the type bars to the printing position, and

during the latter part of said movement they apply a pressure bar to the type bar in order to effect the printing.

The type bars are arranged each with two characters and means are provided whereby the movement of the type bar is stopped wheneither of the characters is over the platen in the printing position. The key during its downward movement must thus move the type bar to either one of two positions and means are provided whereby these positions are determined.

In the drawings 5 represents a frame provided with sup ports for the pintles such as 6 of the platen 7 and with a plurality of brackets such as 8 for supporting the pintlessuch as 9 of the type bar operating levers 10, 11, 12 and 13. The brackets which support the pintles 9 for the levers 11, 12 and 13 are omitted for the sake of clearness.

A bracket such as 14. is also provided for the support of the pressure bar key levers 15, 16, 17 and 18 which are pivoted in said brackets on pintles such as 19. The bracket 14 also has extensions for supporting the pintles such as 20 of the key levers 21, 22, 23 and 24:. One of these extensions is shown as at 25, the other extensions being omitted for the sake of clearness.

Each of the key levers is pivotally connected as at 26 with the corresponding relief levers 10, 11 12 and 13 and the latter are pivoted on the pintles 9 and connected to the corresponding type bar operating levers by springs such as 35. Springs such as 27 are mounted between the pressure bar key levers 17 and 18 and the key levers 21 and 22.

Similar springs are mounted between the pressure bar key levers 15 and 16 and the pusher bars 28 and 29 which are pivotally connected at their upper ends to the key levers 23 and 24, respectively.

Buffers such as 30 of rubber or any other suitable material are mounted upon each of the pressure bar key levers, the key levers and the pusher bars where the same contact,

in order to diminish shock and eliminate noise.

The type bar operating levers 10, 11, 12 and 13 are each pivotally connected at their upper ends with a sleeve 31 and said sleeves are secured upon the type bars 32, 33 and 34 by the pin 37.

The type bars 32, 33 and 34 are slidably mounted in a cross bar 38 which extends across the typewriter and is secured at its ends to the frame 5. The cross bar 38 is provided with a slot for each'of the type bars 32, 33 and 34 and springs such as .39 secured to the corresponding type bar operating levers and sleeves 31 serve to normally keep said type bars against the pads 36 in the tops of said slots.

Each type bar has upon its lower side characters such as 40 which may be the upper and lower case characters or differing in any desired manner. Directly above each of'the characters 40 each type bar has a cone 41 which registers with the conical depression 42 in the pressure bar 43 when the type bars are moved toward the right for the purpose of printing, as shown dotted with reference to the type bar 32 in Fig. 1.

The pressure bar 43 has cylindrical extensions 44 at the top which are slidably mounted in holes provided in the cross bar 45, the ends of which are secured to the framework of the machine.

The pressure bar 43 is provided with limbs 46-46 inclosing an opening for the passage therethrough of the type bars. Said limbs are joined together at their lower end and form the downward extension 47 which is pivoted as at 48 to the pressure bar operating lever 49. The lever 49 is pivoted as at 50 in the bracket 8 and the spring 51 normally keeps the pressure bar 43 in the position shown in Fig. 1.

The lever 49 has at its forward end a bar 52 which extends crosswise of the typewriter and bears at its underside on the noses 53 of the levers 15, 16, 17 and 18.

A buffer 54 mounted on the frame 5 serves as a downward stop for the noses 53 which are kept against said buffer by springs such as 55 which are mounted between the frame 5 and the forward ends of the levers 15, 16, 17 and 18.

The shift key 56 is slidably mounted ,in the cross bar 45 and is kept in either the position shown in Fig. 1 or in its lower position by the spring 57 which enters notches such as 58 in said shift key. The shift key has at its lower end the shift bar 591 provided with a buffer 60 on its front si e. 1 The usual paper shield 62, ribbon 63 and paper roller 64 are provided.

Instead of using the shift bar 59 to de termine the character 40 on each type bar that is to print, I may use the stop bars 65 which extend across the machine and are joined together at their ends by the connecting pieces 66. For the sake of clearnessthe connecting piece at 66 at the right hand side of the typewriter is omitted.

The pieces 66 are slidably mounted at their ends in guides 67 which are supported by the frame of the machine.

The lower bar 65 is connected by the rod 68 with the lever 69 which is pivoted at 70 upon the frame 5.

The lever 69 extends to the front of the machine and is furnished with a handle (not shown) by which it can be moved to an upper and a lower position. The spring 71 is fastened to the frame 5 and engages the notches 72 to hold the lever 69 in either of said positions.

Pads 73 are secured upon the enlarged ends of the sleeves 31 and pads 74 secured on the relief levers 10 11 and 12 and 13 are located to contact with the type bar operating levers such as 10, 11 and 12, re-

spectively, for purposes hereinafter explained.

The typewriter is furthermore provided with an usual or desired appurtenances not shown for the purpose of guiding and feeding the paper and effecting the traverse and revolution of the platen. These appurtenances being old. and well-known in the art form no part of my present invention.

The operation of my improved typewriter is as follows When the operator depresses one of the keys. the corresponding key lever is moved and during the first motion of said lever, the corresponding relief lever such as 10 is moved on its pintle in a clockwise direction and through the spring 35 it similarly moves the lever 10. The motion of the lever 10 moves the sleeve 31 towards the right and moves the corresponding type bar 32 to the printing position. If the shift bar 59 is in the position shown in Fig. 1 the type bar will be moved until the pad 73 contacts with the bar 38 and the left, or lower case character 40 will be in position to make the impression. Durin the first part of the movement of the key, the corresponding spring 27 will be compressed and finally the buffers 3030 will contact. When the buifers30-3O contact, the further movement of the key depresses the corresponding pressure bar key lever 15 and the corresponding nose 53 raises the bar 52, thus moving the right end of the lever 49 downwardly and bringing the depression bar 42 into contact with the cone 41. The further downward movement of the pressure bar brings the left character 40 into lit" contact with the ribbon 63 and then presses It is to be noted that when the end of the type bar 32 strikes either the pad 60 or the pad 73 strikes the bar 38, then the pad 74 on the lever moves from contact with the lever 10 and the spring 35 holds the end of the type bar 32 against the pad 60 or the pad 7 3 against the bar 38.

The downward movement of the type bar 32 is accomplished against-the resistance of the spring 39.

When the operator releases the key the pressure bar 43 is raised by the spring 51 and the spring 39 raises the type bar 32. The further upward movement of the key withdraws the type bar 32 to the position shown by full lines in Fig. 1.

Thus it will be seen that I provide means for insuring heavy and direct pressure of the characters upon the ribbon, for it is evident that the pressure bar 43 must always move in a direct line towards the platen; consequently, any uneven printing of the characters is prevented.

Furthermore, by having the first movement of the keys to advance the character and the latter portion of the movement of said keys to effect the printing, I attain the additional force upon the pressure bar due to the stopping of the keys, thus relieving the operator from the necessity of producing a heavy downward pressure.

If the stop bars 65 are used in place of the shift bar 59, then if the parts are as shown in Fig. 1, the type bar 32 will move until the pad 7 3 strikes the bar 38; that is, to the dot ted position and the left or lower case character will make the impression. If the operator moves the lever 69 until the upper notch 7 2 engages the spring 71, then the bars 65 will be moved downward into the path of the pads 73 on the enlarged ends of the sleeves 31 and the type bar 32 will be stopped with the right or upper case character 40 in position to make the impression.

While I have shown one embodiment of my invention, it is to be understood that I do not desire to be limited to the specific features set forth therein, for many changes may be. made in the various elements and combinations herein shown and described without departing from the spirit of my invention.

I claim 1., In a typewriter comprising a frame, the combination of a. key lever, a pressure bar key lever operated by said key lever, a spring mounted between said levers and a second spring mounted between said second named lever and said frame, said first named spring being weaker than said second named spring, whereby said key lever moves before said second named lever moves, a type bar operated by said key lever and apressure bar operated by said second named lever.

2. In a typewriter comprising a frame and platen, the combination of a plurality of key levers pivoted to said frame, a plurality of. second levers pivoted to said frame, a spring on each of said second levers for moving the corresponding key lever to normal position, a spring on said frame for moving each of said second levers to normal position, means for moving each of said second levers by the corresponding key lever after the first part of the movement of said key lever is accomplished, means for restoring said second lever to normal position after each displacement therefrom, a third lever' movable by each of said second levers, means for restoring said third lever to normal posltion after each displacement therefrom, a' type bar movable to printing relation by each of said key levers, and a pressure bar operated by said third lever for pressing said type bar toward said platen.

In testimony whereof, I afiix my signature.

' SCOTT H. PERKY.

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