US2284702A - Variable spacing mechanism for typewriters - Google Patents

Description

2 Sheets-Shet 1 J. L. WEBB June 2, 1942.

VARIABLE SPACING MECHANISM FOR TYPEWRITERS Filed Do'. 28, 1940 June 2, I J. L. WEBB v I VARIABLE SPACING MECHANISM FOR TYPEWRITERS' Filec lDeci 28, 1940 2 Sheets-Sheet 2 "I'll-ll- J I Z7 59 62595 i amqs Lit 655' Patented June 2, 1942 PATENT OFFICE VARIABLE srAcmG MECHANISM FOR TYPEWRITERS James L. Webb, Gainesville; Tex. I Application December 28 1940, Serial No. 372,128

8 Claims.

This invention relates generally to the class of typewriters and pertains particularly to improvements in spacingmechanism, the present device being directed primarily to a novel means of automatically producing variable spacing. v

The primary object of the present invention is to provide an improved mechanism by means of which a typewriting machine when operated, will move the paper carriage or platen varying distances, as the keys and type bars are operated, according to the sizes of the letters or characters printed instead of moving the platen always a fixed distance as is done in typewriters which are at present in use.

Another and more specific object of the invention is to provide a spacing mechanism for typewriters whereby provision is made for moving the paper carriage or platen three different distances according to the character or letter printed as, for example, a short spacing or movement of the carriage is effected in connection with the printing of periods, commas, lower case ii and other small characters; a second and wider spacing is effected upon the printing of lower case a, b, c and other medium-sized characters and the numerals 1, 2, 3, etc.; and a still greater spacing or movement of the carriage is effected upon printing capital letters and other large characters.

Still another object is to provide in. a typewriter a novel mechanism whereby the spacing or movement of the carriage through the different distances stated is effected automatically with the operation of any one of the keys and type bars of the machine,

A still further object is to provide a variable spacing mechanism for the purpose described wherein such variable spacing is effected by the novel formation of heels adjacent the pivoted ends of thetype bars. v 4

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanyassociation with fragments of a typewriting machine frame and type keys. U

Fig. 2 is a view in rear elevation of the escapement mechanism showing the parts in position for the movement of the platen carriage through the shortest space or extent of its movement.

Fig. 3'is a sectional view taken substantially on the line 3-301? Fig. 1, and showing the relative positions of the dogs and the ratchet wheel.

Fig. t is a plan view similar to Fig. 3, but showing the dogs in their "at rest position after the pawl has turned for the movement of the carriage, a portion of the structure being in section.

Fig. 5 is a detailed section taken on the line 55 of Fig. 1.

Fig. 6 illustrates the heels of a group of type bars showing variations in the contoursof the heels.

Referring now more particularly to the drawings, a portion of a typewriter frame is shown in Fig. 1 in broken or dotted lines and is indicated' by the numeral I. The numeral 2 designates the usual type bar -bearing or segment which is disposed transversely of the typewriting machine frame and which carries the pivot rod 3 upon which the type keys are mounted. This bar bearing has the usual vertical slots or radial slots 4 in which the heels of the type bars enter ing drawings forming'part of this specification,

with the understanding, however, that the invention is not to be confined to any strict conformity with the showing of the drawings but may be changed or modified solong as such changes or modifications mark no material departure 5 from the salient features of the invention as expressed in the appended claims.

In the drawings:

Fig. 1 is a view in perspective of the mechawhen the bars are swung upwardly on the pivot 3 for bringing the type face against the platen cylinder 5.

For the purpose of the present invention, the bearing 2 is provided at its rear face with the relatively wide channel 6 into which the slots 4 open and in which is disposed the universal bar key bars carry the pull links l3 which are pivotally attachedthereto and each, of which extends upwardly and carries a pivot pin 9, as shown, and it will thus be seen that upon depression of any one of the key bars, the type bar coupled therewith by the link l3 will be rocked into typing position with respect to the platen roll 5.

nism embodying the present invention shown in It is, of course, understood that the showing for the mounting of the key bars and the connections between the key bars and the type bars is merely conventional and that any other suitable operative connections may be employed or any other suitable mounting for the key bars may be made use of without departing from the spirit of the present invention, and this applies also to the mounting for the hereinafter described shift key and for the connections between this shift key and the platen lifting shift rail.

The shift rail for the platen roll is indicated by the numeral l4 and upon this rail the platen moves across the machine in the usual manner. The numeral I5 designates ashift key bar which is suitably pivotally supported, as at [5, upon the" frame and which has at its outer end the key II. The inner. end of the shift key bar is connected by a link I8 with a short pivoted rock bar l9, which is pivotally mounted intermediate its ends by the trunnion 20 engaging a suitable portion of the frame, the link l8 being pivotally at- The other tached to one end of this rock bar. end of the rock bar 20 is attached to a shift bar 2| which extends transversely of the machine and may be attached at its opposite end, if desired,- to an opposite rock bar, not shown, corresponding to the bar l9.

The platen shift rail I4 is supported upon the upper end of one or more vertical supporting arms 22, the lower end of the am being pivotally attached, as at 23, to the rear end of the rock bar I9. Thus it will be seen that upon depression of the shift key I1, the supporting arm 22 will be raised so as to raise the shift rail and the platen roll and the rock bar 2| will be lowered.

Rearwardly of the universal bar there are provided the two upright arms 24 which are in spaced parallel relation and each of which is pivotally attached at its lower end with a suitable part of the machine frame, as for example, by means of the laterally turned lower end trunnions 25. The upper ends of the arms 24 are connected by a horizontal rail 26 to which is rigidly secured the upstanding post 21.

Pivotally attached to the post supporting rail 25 at opposite sides of the post 21, are -the forwardly extending universal bar arms 28, each of which is coupled to the under side of the universal bar 1 by means of the ears 29, as shown in Fig. 5. These arms support the universal bar within the channel 6 and with an edge of the bar directed toward the slots 4 of'the breast block, as previously described. The forward ends of the universal bar arms are supported from the rock bar 2| by the vertical supporting links 30. These links are pivotally attached at their ends to the arms and the rock bar, as will be readily understood, so that when the rock bar is raised and lowered, the'universal bar may be shifted vertically in the channel 6 without forward or rearward swinging movement.

The numeral 3| designates the shaft of the typewriting mechanism which supports the usual gear 32, which is coupled with the rack, not shown, which forms a part of the platen supporting carriage, not shown. With this shaft 3| there is connected the escapement mechanism ratchet wheel 33 which turns in a clockwise direction, when viewing the machine from the rear, under the urge of the carriage moving spring, not shown. The teeth of the ratchet wheel are indicated by the numeral 34 and as is most clearly shown in Fig. 2, each tooth has a radial straight edge 35 which faces in the direction of movement of the wheel, the opposite edge of the tooth being curved or rounded, as indicated at 36. This wheel forms a part of the escapement mechanism, as will be readily understood, and it will be seen upon reference to Fig. 2, that the post 21 extends vertically across the rear face of the wheel to one side of the pivotal center thereof.

Upon the upper end of the post 21- is a right angularly extending relatively long head 31 which is directed across the periphery of the ratchet wheel and upon one side edge of this head there is formed a stop lug 38, the function of which will be hereinafter described. This stop lug, it will be noted, is upon the side of the head nearest the pivotal center of the ratchet wheel.

Extending from the inner end of the head 31 are the two pins 39 and 49. The pin 39 has a head 4| upon its outer end. The pins 39 and 40 pass through and have slidably mounted thereon the dog 42 which extends from the side of the head nearest the pivotal center of the ratchet wheel or in the same general direction as the stop 38 and has at its free end the ratchet wheel engaging tooth 43. This tooth 43 extends only partway across the width of the dog and upon the side of the dog remote from the stop 38 there is formed the finger 44 which extends beyond the edge of the tooth 43 and engages a. side of the ratchet wheel at certain periods in the operation of the ratchet mechanism.

As previously stated, the dog 42 is mounted upon the two pins 39 and Hand it has a slid ing movement upon these pins but is normally urged toward the head 31 by the expansion spring 45 which encircles the pin 39 and is interposed between the head 4| and the dog 42.

At the rear end of the dog 42 a stop finger 46 is carried and attached to a suitable fixed part of the machine adjacent the rear of the head 31 is a bracket 41 which carries a depending pivot stud 48 on which is rotatably mounted a bumper roller 49. This roller is engaged by the rear of the dog and head, as shown in Fig. 4, and serves as a bracing means for the head and the head supporting post. When the escapement mechanism is in one position of its operation, the pin 46 carried by the dog 42 will be engaged against the side of this stop roller 49, but normally when the escapement mechanism is inoperative, the roller will engage the dog and the head at the point of joinder between these parts, as shown in Fig. 4.

Secured to and extending from one side of the head post 21 is a bracket finger 50 which carries a pivot pin 5|, which is approximately on the axial center of the shaft 3|, and this pivot pin supports a rocking or spacing pawl arm 52 upon the upper end of which is the laterally extending spacing pawl 53 which is directed toward the teeth of the adjacent ratchet wheel. 'I'he free end of the spacing pawl 53 is cut obliquely as shown in Figs. 3 and 4, so that the pawl is provided with a relatively sharp point 54. Adjacent this point the pawl carrie the depending spacing lug 55, the purpose of which will be hereinafter described.

Extending from the lower'end of the pawl arm 52 is a finger 56 which is connected by a contractile spring 51 with the adjacent post 31. This spring normally urges the oscillation of the pawl arm 52 and the pawl 53 away from the post and in a direction counter to the direction of movement of the ratchet Wheel 33.

Supported in a suitable manner at the rear of the ratchet wheel 33 as, for example, upon a is disposed within the area defined by the teeth of the ratchet wheel and spaced from the rear face of the ratchet wheel, as is clearly shown in Figs. 3 and 4. Upon theupper side of this arm 59 are mounted the three stops 60, (ii and 62, these stops being arranged, in the order numbercd in spaced relation with one another and forming the free end of the arm and being in the order numbered of increasing width across the arm. The sides of these stops nearest the ratchet wheel 33 are all in the same plane and flush with the edge of the arm, and thus it will be seen particularly upon reference to ,Figs. 1 and 4, that the opposite edges of the stops, being those edges remote from the ratchet wheel 33, are in stepped relation.

In the normal position of the mechanism the arms 24 may be considered as being substantially vertical, the normal center line for each, of these arms being indicated by the broken lines 53 in Fig. 1. When the arms are in normal position, all of the type bars will, of course, be lowered, and control springs 64 connected with the arms 24 will maintain the arms in this. normal position with the universal bar forward in the channel 6. Under these conditions, the movement limiting or movement controlling pawl 53 will have its point engaged acros the straight edge of a tooth of the ratchet wheel. Also the point or tooth 43 of the dog 42 will be out of engagement with the ratchet wheel, but will be in alinement with the tooth engaging 'edge of the pawl 53. Since there will be a tendency for the ratchet wheel 33 to turn under the urge of the carriage control spring of the typewriter mechanism, the movement controlling pawl'53 will be held by the ratchet wheel against the stop 38 of the head 31 and the spring 51 will be stretched and under tension.

Fig. 6 illustrates the heel portions ofa number of type bars B and at the lower end of each type bar there is formed a heel which functions as a universal bar actuating cam, and these heels of a the various type bars are of varying heights and contours according to the character of the type faces which form a part of the bar. For example, in Fig. 6, one of the type bars B has a heel portion 13 in the form of a relatively flat are, this being the lowest type of heel and being used in conjunction with the type bar carrying periods, commas, lower case i and other small letters and characters. Another heel is indiacted at 13 in which theme is somewhat sharper than that of the heel B such a heel being employed, for example, upon type bars having certain numerals and characters such, for example, as the figure 4 and the dollar sign, as shown. The heel B is still more sharply formed in its contour and bulges nearer to the lower end of the key than do the heels B and B This heel The character B designates a heel which would be a part of .the type bar carrying the lower case 1 and the capital I. The operation of this heel would also be the same as that described in connection with the heel B In the operation of the mechanism, when a type bar is actuated in the customary manner, as it swings upwardly toward the platen, the heel of the bar will move into the slots 4 and press against the universal bar I, so as to force the universal bar rearwardly; This will, of course, effect the rearward oscillation of the arms 24' against the tension of the springs 64 and it will also move the post 21 and the head 31 rearwardly together with the parts connected to the post and head. Assuming that the type bar in question is one having a relatively flatly curved heel such, for example, as the heel 13 for the printing of a period, comma, semi-colon, lower case '1 or other small character, the universal bar will be moved rearwardly to the minimum extent-and the escapement mechanism will function in the following manner to release the platen carrying carriage for the making of the smallest space. This operation takes place-as follows. When the post 21 is swung rearwardly under the action of the small space producing heel, the movement controlling pawl 53 will be shifted away from the tooth of the ratchet wheel with which it is engaged, but before it releases this tooth, the tooth of the dog will follow it into engagement with the ratchet wheel tooth and function to hold the ratchet wheel against turning. In this position the tooth of the dog 42 is illustrated in Fig. 1. As soon as the pawl 53 releases the ratchet wheel tooth, the spring 51 will oscillate the pawl arm and it will swing around until it strikes the first or narrowest one of the stops carried by the arm 59, which is the stop 60. These stops are spaced apart distances equal to thedistances between the straight edges of the ratchet wheel teeth and the first stop or smallest stop with which the pawl 53 comes into contact is removed the space of one tooth from the ratchet wheel tooth which the pawl has just released. As a result, it will be seen that the pawl 53 will be oscillated a distance equal to the space of one tooth of the wheel where it may be brought to a stop through the engagement of the lug'55 with the first stop 60. When the type bar moves back away from the universal bar, the arms 24 will be again moved forwardly would be employed in connection with the lower case a and capital A, the'upper part of the heel operatin the universal bar when the lower case a, is typed, and the lower part of the heel engaging theuniversal bar when the shift key has been actuated for the printing of the capital letter. It will, of course, be understood that when the shift key is actuated, the rock bar 2| will be lowered so that the universal bar will be dropped or lowered in the channel, and thus it will be in the proper position to be engaged by the highest point of the heel l3 and,

by the springs 64 and the pawl and dog of the release or escapement mechanism will be shifted back to their former positions, but the pawl 53 will then enter the next tooth of the ratchet wheel as'the dog releases the toothwhichthe pawl had previously engaged. The carriage controlling spring of the typewriter will then cause the shaft 3| to turn so as tomove the platen over the distance of the smallest space movement permitted by the mechanism and as, the ratchet wheel 33 turns under the action of the carriage moving spring, it will swing the pawl 53 over until it is brought into engagement with and stopped by the finger 38 carried by the head 31. This movement will be equal to the width of one tooth of the wheel and it will be understood that the tooth of the dog 42 and the ratchet wheel tooth engaging edge of the pawl 53 will again be in alinement.'

' If a type bar bearing a capital letter such as A or L is actuated, the shift key will have, of course, been moved so that the universal bar therefore, the proper spacing will be obtained. 7 I will be lowered and consequently will be in a position to receive the maximum thrust from the heel of the type bar. This will swing the post 21 and the head 3'! to the maximum distance as a result of which after the pawl 53 moves from out of engagement with the tooth of the, ratchet wheel and the dog tooth moves into engagement with such ratchet wheel tooth, the pawl will be moved back far enough for the lug 55 to pass the first, two stops 60 and 6| and be finally brought into engagement with the third stop 62. In this movement the ,pawl 53 will pass two ratchet wheel teeth being brought into engagementwith the edge of the third tooth'from the one which it previously engaged. The dog 42 will not move over any farther than it moves for the production of the minimum amount of movement of the carriage since the terminal portion ll of the dog engages the forward side of the ratchet wheel but relative movement is permitted between the dog and the head 31 by the sliding of the dog on the pins 39-40 against the tension of the spring 45. After the type bar is released and the head moves back to its former position,'the dog will maintain its hold on the ratchet wheel until the head comes back into engagement with it, at which time the point of the pawl 53 will be moving into engagement with the edge of the third tooth so that the dog may then release the ratchet wheel, and it will be understood that the ratchet wheel will then turn the distance of three teeth and carry the pawl with it back to the initial position of the pawl. against the stop finger 38 carried by the head. This will permit the turning of the shaft 3| and the gear 32 to the extent necessary to move the carriage and platen of the machine the maximum distance.

From the foregoing, it will be readily apparent that the mechanism herein disclosed is of relatively simple construction and at the same time will function efficiently to produce the diiferent degrees of movement of the machine carriage in accordance with the size of the letter or character being printed and, therefore, more balanced spacing between the letters will be obtained with a consequent improvement in the appearance of the typed word or line.

While the invention as illustrated and described sets forth a means for producing only three degrees of spacing or means for producing three dilierent widths of spacing, it will be readily apparent that the idea may be carried forward for the production of a machine in which four or five widths of spacing may be obtained, if desired. This would, of course, be accomplished by changing the size of the teeth of the ratchet wheel 33 and by correspondingly increasing the number of stops carried by the arm 59.

What is claimed is: I

1. In a typewriting machine having a carriage actuated rotatable shaft and type bars pivotaliy supported for swinging movement, means for effecting variable movement of the carriage in accordance with difierent widths of characters carried by the bars, comprising heels of difierent contours on the type bars and bearing definite relations to the widths of the characters carried by the bars, a universal bar supported to be actuated by the heels on movement of the bars in said universal bar. being actuated to diiferent degrees by the difierent contour forms of the heels, and an escapement mechanism forming an operative coupling between said shaft and said universal bar to be controlled by the universal bar, said mechanism including a ratchet wheel, a pawl and a dog coupled with the universal bar and alternately engaging the ratchet wheel upon movement of the bar, the ratchet wheel having different degrees of turning movement upon release by the dog and engagement by the pawl, and means cooperating with the pawl for efiecting regulation of the degree of turning of the ratchet wheel in direct proportion to the degree of shift given the universal bar by a type bar heel.

2. In a typewriting machine having a carriage actuated rotatable shaft and type bars pivotaliy supported for swinging movement, means for effecting variable movement of the carriage in accordance with different widths of characters carried by the bars, comprising heels of different contours on the type bars and bearing definite relations to the widths of the characters carried by the bars, a universal bar'for engagement by said heels and supported to be shifted to diiferent degrees by' the different contour forms of the heels, an escapement mechanism including a toothed wheel carried by said shaft and a'pair of pawls cooperating for alternate engagement with the wheel teeth, means for supporting the pawls which is operatively coupled with said universal bar to be moved with and by the same, one of said pawls being normally engaged with a wheel tooth, means supporting the said one pawl for movement independently of its movement with its support when the support is moved to disengage the pawl from the said wheel tooth, the other pawl engaging said tooth and holding the wheel when the said one pawl is disengaged therefrom, means causing said independent movement of said one pawl when disengaged from the wheel and means for limiting said independent movement of the other pawl to one of a number of positions with respect to the wheel teeth according to the degree of shift given said universal bar, the said other pawl releasing the wheel and the said one pawl re-engaging the wheel upon release of said universal bar by the heel, the said wheel returning said one pawl to its first position after its independent movement and re-engagement with the wheel.

3. In a typewriting machine having a carriage actuated rotatable shaft, a type bar supporting bearing and type bars pivotaliy supported on the bearing, means for effecting variable movement of the carriage in accordance with the different widths of characters carried by the type bars, comprising heels carried by the type bars and having difierent contour forms, said bearing having a slot therein into which the heels enter upon movement of the bars into typing position, the contour forms of the heels bearing a definite relation to the widths of the characters carried thereby, an oscillatable structure spaced from the channel of said bearing, said structure including a universal bar disposed in the channel for engagement by the heels, an escapement mechanism including a toothed wheel carried by said shaft and a pair of pawls supported upon said oscillatable structure to be moved therewith relative to the toothed edge of the wheel,'one of said pawls being normally engaged with a tooth of the wheel to hold the same against turning, the other pawl being alined with the said one pawl and moving into engagement with said tooth upon the shifting of the pawls by the oscillatable structure, the said one pawl having movement independent of its movement with its support when the support is moved for disengagement of the one'pawl with the tooth, means for limiting the said independent movement of the one pawl to one of a number of positions with respect to the wheel teeth according to the degree of shift given the universal bar and the oscillatable supporting structure by atype bar heel, the said other'pawl releasing the wheel and the said one pawl re-engaging the wheel upon release of the universal bar by the heel, the wheel returning the said one pawl to its first position after its independentmovement and re-engagement with the wheel, and case shift means coupled with and operating to raise and lower said universal bar in the channel of said bearing for changing the points of contact of the heels with the universal bar and correspondingly changing the extent of movement of the carriage according to the width of the character printed.

4. In a typewriting machine having a carriage actuated rotatable shaft and type bars pivotally supported for swinging movement, means for effecting variable movement,of; the carriage in accordance withthe different widths of the characters carried by the bars, comprising a toothed wheel carriedby said shaft, a pivoted pawl bodily movable into and out of engagement with the teeth of the wheel and normally securing the shaft against turning, means for oscillating the pawl on its pivot in a path corresponding with the circumferential line of the wheel when the pawl is bodily released from a tooth, a second pawl cooperating with the first pawl to engage the toothed wheel and maintain it against movement when the first pawl is initially bodily released therefrom, the second pawl releasing the toothed wheel upon re-engagement of the first pawl-with a tooth thereof after the first pawl has moved a prescribed distance along said circumferential path, a series of stops arranged in a curved line concentric with the path of movement of the first pawl and arranged for selective engagement by the first pawl according to its extent of movement out of engagement with the wheel, a shiftable element operative coupled with said pawls for imparting movement in one direction thereto for effecting disengagement of the first pawl from the wheel and engagement of the ,second pawl therewith, and means carried by the type bars and bearing a predetermined relation to the widths of the printing characters carried thereby for imparting movement in the said one direction to the shiftable element and to the pawls to free the first pawl from the wheel for a predetermined engagement with one of said stops to control the extent of the subsequent movement of the carriage.

5. In a typewriting machine having a carriage actuated rotatable shaft and type bars pivotally supported for swinging movement, means for effecting variable movement of the carriage in accordance with different widths of characters car- 'ried by the bars, comprising heels of different contours on the type bars and bearing definite relations to the widths of said characters, a universal bar arranged for engagement by said heels on movement of the bars for printing, a support for said universal bar having limited movement in two opposite directions, a toothedwheel secured to said rotatable shaft, a post carried by said support and disposed adjacent said wheel, a pair of pawls supported by the h post and having movement across the edge of the wheel upon movement of said support, one of said pawls normally engaging a tooth of the wheel to hold the latter against turning and disengaging the wheel upon movement of the support in one direction, the other pawl moving into engagement with a tooth of the wheel upon disengagement of the said one pawl therefrom, the said one pawl being pivotally supported on the post to swingwhen disengaged from the wheel, in a path following the circumference of the wheel, the said one pawl re-engaging the wheel at another tooth upon movement of the support in the opposite direction and said other pawl simultaneously releasing the wheel, and means for regulating the extent of swinging movement of the said one pawl in said path I which is controlled by the degree of thrust given to the said universal bar by a heel.

6. In a typewriting machine having a carriage actuated rotatable shaft and type bars pivotally supported for swinging movement, means for eifecting variable movement of the carriage in accordance with different widths of characters carried by the bars, comprising heels of different contours on the type bars and bearing definite relations to the widths of said characters, a universal bar arranged for engagement by said heels on movement of the bars for printing, a support for said universal bar having limited movement in two opposite directions, a toothed wheel secured to said rotatable shaft, a post carried by said support and disposed adjacent said wheel,

a pair of pawls supported by the post and having,

' the other pawl moving into engagement with a tooth of the wheel upon disengagement of the said one pawl therefrom, the said one pawl being pivotally supported on the post to swing when disengaged from the wheel, in a path following the circumference of the wheel, the said one pawl re-engaging the wheel at another tooth upon movement of the support in the opposite direction and said other pawl simultaneously. releasing the wheel, a lug carried by the saidone pawl, a

plurality of stops supported in a curved line sub-' stantially corresponding to the curvature of the periphery of the wheel, the stops being spaced apart distances substantially equaling the width of the teeth, said lug being selectively engaged against the stops in the swinging of the said one pawl in accordance with the extent of movement of the support in the said one direction, and the said extent of movement of the support in the said one direction being controlled by the form of the heel engaging said universal bar.

'7. In a typewriting machine having a carriage actuated rotatable shaft and type bars pivotally supported for swinging movement, means for effecting variable movement of the carriage in accordance with different widths of characters carried by the bars, comprising heels of different contours on the type bars and bearing definite relations to the widths of said characters, a universal bar arranged for engagement by said heels on movement of the bars for printing, a support for said universal bar having limited movement in two opposite directions, a toothed wheel secured to said rotatable shaft, a post carried by said support and disposed adjacent said wheel, a pair of pawls supported by the post and having movement across the edge of the wheel upon movement of said support, one of said pawls normally engaging a tooth of the wheel to hold the latter against turning and disengaging the wheel uponmovement of the support in one direction,

the other pawl moving into engagement with a tooth of the wheel upon disengagement of the said one pawl therefrom, the said one pawl being pivotally supported on the post to swing when disengagedirom the wheel, in a path following the circumference of the wheel, the said one pawl re-engaging the wheel at another tooth upon movement of the support in the opposite direction and said other pawl simultaneously releasing the wheel, 9. lug carried by the said one pawl, a plurality of stops supported in a curved line substantially corresponding to the curvature of the periphery of the wheel, the stops being spaced apart distances substantially equaling the width of the teeth, said lug being selectively ena ed against the stops in the swinging of the said one pawl in accordance with the extent of movement of the support in the said one direction, and the said extent of movement of the support in the said one direction being controlled by the form of the heel engag said universal bar, said universal bar being shiftable vertically, a case shift mechanism and means coupling the case shift mechanism with the universal bar for efiecting vertical movement of the universal bar on actuation of the said mechanism to change the points of contact between the contoured heels and the universal bar to effect a desired greater or lesser degree of movement in the said one direction of the support.

8. In a typewriting machine having a carriage actuated rotatable shaft and type bars pivotally supported for swinging movement, means for efifecting variable movement of the .carriage in accordance with difierent widths of the characters carried by the bars, comprising heels of diilferent contours on the type bars and bearing definite relations to the widths of said'characters, a universal bar, a movable support for the universal bar maintaining the latter in position for.

engagement by the type bar heels on swinging of the bars to typing position, the engagement of a heel with the universal bar moving the support backwardly in the machine, a toothed wheel secured to said shaft to be turned thereby, a post carried by the support adjacent the wheel, a head on the post, a pawl supported on the head for movement relative thereto and in a position to engage a wheel tooth when the head is moved with the support rearwardly, a second pawl supported by the post and normally engaging a wheel tooth to maintain the wheel against turning and released from the wheel upon the rearward movement of the support, the second pawl being pivotally supported for independent movement upon its release from the wheel in a path following circumference of the wheel, the pawls being relatively arranged whereby the first pawl immediately engages the wheel and holds the same upon release of the wheel by the second pawl, a plurality of stops supported adjacent the wheel and arranged in an arcuate path paralleling the path of swinging movement by the second pawl, said stops being separated distances equal to the distances between the teeth of the wheel, a lug carried by the second pawl for selective engagement with the stops, said stops being further so arranged that the one selected for engagement by the lug is determined by the extent of rearward movement given the support and the second pawl by the type bar heel engaging the universal bar, and said second pawl engaging an-

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