US2339423A - Means for producing characters - Google Patents

Description

Jan. 18, 1944. J. H. POLLARD 2,339,423

MEANS FOR PRODUCING CHARACTERS Filed June 10, 1940 2 Sheets-Sheet 1 Jan. 18, 1944. J PQLLARD 2,339,423

MEANS FOR PRODUCING CHARACTERS Filed June 10, 1940 2 Sheets-Sheet 2 amen 1M c/o/m fol/arc Patented Jan. 18, 1944 2,339,423 MEANS FOR PRODUCING CHARACTERS John H. Pollard, Dallas, Text, assignor of onehalf to Arthur S.

Baron, and one-half to Richard Bur-dick, Dallas, Tex.

Application June 10, 1940, Serial No. 339,628 9 Claims. (Cl. 101-126) This invention relates to new and useful improvements in means for producing characters.

One object of the invention is to provide improved means whereby characters, such as letters, figures, symbols, objects and the like, may be readilyand economically produced with plastic material, paint, or other compositions upon pervious or foraminous or impervious surfaces, whether rough or smooth.

An important object of the invention is to provide improved means involving the passing of a heated plastic, semi-plastic or solid compound, composition or paint through a stencil, pattern, form, or the like, whereby characters may be produced on a medium particularly on an open mesh wire fabric, such as is used for windows and doors, but also on other surfaces; the use of the heated compound facilitating solidifying of the characters and thereby eliminating the necessity of waiting relatively long periods of time for the characters to dry and reach a hardened state, said heated compound also eliminating the necessity of using a backing or retaining means on the medium.

Another object of the invention is to provide an improved apparatus for producing characters, wherein the stencil carrier has a heating means associated therewith, whereby the particular composition which is employed for forming the characters may be maintained at a desired temperature to maintain said composition in a softened and plastic, semi-plastic or workable state.

A particular object of the invention is to provide an improved apparatus, of the character de scribed, having astencil carrier which is formed with receptacles or troughs at its edge portions for receiving the composition or material, together with means for heating said receptacles or troughs to maintain the material therein in a softened state, or in the case where a plastic is employed, to remove excessive moisture; the apparatus also including an auxiliary heating unit which aids in heating the material and which also heats the stencil when said stencil is in an inactive or raised position out of engagement with the medium on which the characters are to be formed.

Still another object of the invention is to provide an apparatus for producing characters, which includes an improved stencil carrier having power driven means for raising and lowering the stencil, whereby the formation of the characters is facilitated and time required for the operation is materially decreased, as compared to manually actuated stencil carriers.

A further object of the invention is to provide an improved apparatus for-forming characters which has a metallic or other heat resistant stencil, whereby the composition of which the characters are formed, may be heated prior to its passage therethrough.

A construction designed to carry out the invention will be hereina ter described, together with other features of the invention.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings, in .which an example of the invention is shown, and wherein:

Figure 1 is a front elevation of an apparatus, constructed in accordance with the invention,

Figure 2 is a side elevation thereof,

Figure 3 is an isometric view of the stencil carrier,

Figure 4 is an enlarged vertical, sectional view, taken through one of 'the receptacles or troughs of the stencil carrier,

Figure 5 is an enlarged side elevation of the carrier, with the central portion of said carrier omitted,

Figure 6 is a transverse, sectional view of the medium having characters formed thereon and showing a. retaining means or backing for said characters,

Figure 7 is a partial plan view of a modified form of stencil, and

Figure 8 is an enlarged, partial transverse, sectional view of the apparatus, illustrating the auxiliary heating unit.

In the drawings, the numeral table which is provided with a fiat top H and which issupported by vertical legs 10a. The table may be of any desired construction so long as the top It provides a fiat surface. A platform 12 is spaced above the table to and is suitably supported on transversely extending beams l3. Vertically extending supports or bars [4 depend from the underside of the platform l2 and are disposed in spaced relation, as is clearly shown in Figure 1. Each of the supports I4 has a guide collar I5 secured thereto and the guide collars are connected to each other by means of a rod l6,'which serves to brace and reinforce said collars. The lower ends of the supports l4 terminate some distance above the top H of the table and since the collars 15 are secured to the lower ends of the support, said collars are spaced from the table top.

Ill designates a A supporting yoke I] is mounted between the I supports l4 and the depending legs l8 of the yoke are slidable vertically through the guide collars IS. The upper end of the yoke is provided with upstanding ears I! and the lower end of a connecting bar or pitman 23 is disposed between said ears, being pivoted to the cars by a suitable pivot pin 2|. The upper end of the connecting bar or pitrnan is formed with an elongate slot 22, which slot receives an outwardly extending pin 23 which is provided on a crank arm 24. The crank arm is fixed on a rotating shaft 25, which shaft is supported in suitable bearing members 26 which are mounted on the platform I2. The shaft 25 has a drive wheel 21 secured thereon and when said wheel is rotated, it will be obvious that the crank arm 24 is also rotated. Due to the connection of the crank arm 24 to the connecting bar or pitman 20 through the pin 23 and slot 22, it will be manifest that a rotation of the crank arm will result in a reciprocation of the yoke l1'with relation to the table topll.

For driving the wheel 21 to impart a vertical reciprocation to the yoke |1, an electric motor 23 is provided. This motor is supported on the platform l2 and has its shaft 29 opcratively connected with the drive wheel 21 through a series of belts and pulleys, as is clearly shown in Figure 1. The connection between the motor shaft 29 and the drive wheel 21 is for the purpose of reducing the speed of the wheel 21 relative to the speed of the motor shaft 29. Obviously, the drive connection between the motor and the wheel is subject to variation.

A stencil carrier A is secured to the lower ends of the vertical legs ll! of the yoke l1, whereby said stencil carrier is movable vertically with relation to the top H of the table. The stencil carrier is clearly shown in Figures 3 to and includes a pair of longitudinal troughs or receptacles 30 which are located on opposite sides of the carrier. The troughs 30 extend in parallel relation to each other and are connected by side plates or members 3| which are suitably secured to the ends of the troughs. Manifestly, the troughs 30, together with the side plates or members 3| provide an open frame. Each side plate 3| is provided with an outwardly extending boss 32 which has an upstanding collar 33 preferably made integral therewith. Each collar 33 receives the end of one of the legs |8 of the yoke and said end is suitably fastened within the collar, whereby the stencil carrier is carried by the yoke. When the yoke I8 is reciprocated vertically by means of the crank arm 24, as has been explained, it will be obvious that the stencil carrier A is raised and lowered with relation to the to'p ll of the table Ill. 8

Each trough 33 of the stencil carrier A is constructed in the same manner and it is believed that a description of one will sufiice. The construction of one of the troughs is clearly shown in Figure 4, and as illustrated, the trough is formed of a single piece of metal, or other material, bent to the proper shape. Adjacent the inner end 30a of the trough 39, the material is bent downwardly in a long curve to provide a sloping surface 34, which surface extends from the inner longitudinal edge of the trough to the bottom of the stencil carrier. After the formation of the surface 34, the material is bent inwardly and is then upset as illustrated at 35. This upset portion 35 overlies the other end portion 36 of the material and is secured to said portion by means of suitable screws :1. By shapmg the material in the manner shown in Figure beneath each trough 30 and this chamber receives a refractory block 39 which has its upper end spaced from the underside of the trough 30. The upper surface of the refractory block 39 is formed with a plurality of recesses 40 each of which receives an elastic heating coil 4|. It will be obvious that when the coils 4| are operated, the trough 30 is heated, whereby any composition C which is retained within said trough is also heated. By regulating the coils 4|, it is possible to maintain the composition within the trough 30 at any desired temperature.

The particular material or composition C, which is placed within the troughs, is adapted to form the display letters, symbols or characters, as will be described. This composition is subject to variation and may be a plastic, semi-plastic or solid' material. If a solid, the composition must be capable of being softened sufficiently to be readily handled, when heated. when cool, the composition C solidifies to maintain a predetermined form, and when in its solid state it is preferable that the composition have a certain amount of flexibility or elasticity. It is particularly pointed out that the composition may be plastic in nature when placed in the trough and heating of such plastic merely removes excessive moisture but the heat is insuflicient to cause the composition to be thoroughly dried out prior to its removal from the trough, as will be explained.

A stencil 42 i adapted to be mounted on the stencil carrier and said stencil may be of any desired material having the desired numerals, letters, symbols or the like cut out therein. iA- though the stencil may be constructed of any suitable material, it is preferably that the same be made of metal, or other material, which will not be adversely affected by heat. The stencil extends completely across the underside of the carrier and has its ends turned upwardly to form upturned flanges 420. which extend contiguous to the vertical sides of the troughs 30, as is clearly shown in Figure 4. The flanges 42a are bolted, or otherwise removably secured to the carrier. In the event that the entire letter, figure or symbol on the stencil 42 is completely out out, then a plurality of wires 43 may overlie the stencil, the ends of said wires being suitably fastened to said stencil by soldering, or otherwise. In this instance, those portions of the stencil which would be unsupported, as for example the part 44 of the letter A in Figure 3, may be soldered or otherwise secured to the supporting wires 43 so as to maintain these portions in their.

proper position. It would be possible to provide a stencil such as that shown in Figure 7, wherein the letters or symbols are not completely out out. When a stencil, such as shown in Figure I is employed the wires 43 may of course, be omitted.

In using the apparatus and practicing the invention,the medium M on which the characters are to be formed is first placed on the table top II. This medium has been shown as an open mesh fabric, such as the usual window screen, but it is pointed out that any medium may be used. The medium M is placed on the table top when the yoke I3 is in a raised position holding the carrier raised, as shown in dotted lines in Figure 1. At this time, the composition C, of which the characters are formed, is disposed within one of the troughs 39 and is suitably heated by the electric heating coils 4|. Such heating of the composition softens the same whereby said composition is plastic or pliable so as to be capable of being readily handled. When the yoke I1 is moved downwardly, this downward movement of the yoke moves the stencil downwardly into contact with the medium M, as is clearly shown in Figure 5. The pressure and weight of the stencil carrier A holds the medium M in position but in order to further aid in holding said medium in position while the characters are formed, as will be explained, each trough is provided with a pair of outwardly extending guide collars 46. A plunger 41 having a bolt head 48 at its upper end is slidable within each collar 46 and the lower ends of the plungers 41 are secured to an elongate retaining bar 49. The bar 49 is constantly urged downwardly by means of a coiled spring 5!), which is confined between each collar 46 and said bar, each spring surrounding one of the plungers 41. With this arrangement, it will be obvious that the retaining bars 49 are disposed one on each side of the stencil carrier A and a plurality of retaining wires 58 extend between the retaining bars 49 and transversely of the medium M on which the characters are to be formed. Therefore, when the stencil carrier A is moved downwardly into engagement with the medium M, the retaining bars 49, as well a the wires 5|, contact the medium M and due to the coiled springs 50, serve to frictionally hold the medium on the table top.

After the stencil has been moved to a proper position, the composition of material C of which the characters are to be formed, and which has been heated to a plastic or pliable state, is scraped from the trough 30 by means of a squeegee 52, as indicated in Figure 5, after leaving the trough, the composition is moved down the inclined sloping surface 34 onto the top surface of the stencil and then across said stencil, whereby said composition is passed or forced downwardly through the openings in the stencil 42 and onto the medium M. When the medium is an open mesh wire fabric, said composition enters the interstices or openings of said medium and adheres thereto and manifestly, the shape of the composition on the medium conforms to the openings in the stencil to farm the characters of the stencil on the medium. After passing over the openings in the stencil 42, that portion of the composition which has not passed through said openings is moved upwardly along the sloping surface 34 adjacent the opposite trough and is then moved into the opposite trough, where it remains until the next operation.

After thecomposltion C has been moved from one trough 30 and over the stencil 42 to the other trough 30, as explained, the characters, a determined by said stencil, are formed on the medium ML The stencil carrier A is then raised upwardly off of said medium. Upon initial upward movement of the stencil carrier A, the stencil 42 immediately leaves the medium M. However, due to the mounting of the retaining bars 49 and the wires 5|, said retaining bars and wires will remain in contact with the medium after the stencil moves upwardly away from said medium. As the stencil carrier continues its upward movement, the expansion of the coiled springs 50 maintains the retaining bars 49 in contact with the medium M until such time as the upper ends of the guide collars 46 engage the bolt heads 48 on the plungers 41. After said collars engage the heads 48, it is apparent that the retaining bars are lifted from the medium and moved with the stencil carrier. It is noted that this arrangement ,display characters.

tion, the composition C has been of a plastic or provides a positive means for holding the medium turn of the drive wheel 21. Referring to Figure 1',-

the stencil carrier A reaches its lowermost position when the crank arm is in the positionB indicated in dotted lines. Said' carrier remains in this position until the crank arm reache the dotted line position indicated at D and it is during this period that the squeegee 52 is manually manipulated to move the composition or material C across the stencil in the manner described. After the crank arm has reached the position D, the stencil carrier begins to move upwardly and continues its upward movement, until the crank arm reaches the position indicated at E, at which time the stencil is in its uppermost position. After passing the-point E the crank arm moves downwardly toward the position B during which time the carrier is again moved downwardly onto the top H of the table. During the time that the crank arm is moving from the position D to the position B, the medium on which the characters have been formed is removed fromthe table and another medium for the next operation.

It is pointed out that the composition C, of which the characters are formed, is maintained in a heated condition at all times and prior to its application to the medium, whereby said composition is maintained in a plastic or softened state. The coils 4| are adjusted so as to maintain the temperature of the composition at the desired point and manifestly, the composition is applied to the medium while in its heated state. Since the stencil is of metal, or'other material not adversely affected by heat, the heat of the composition which is passed through said stencil does not affect the same. It has been found that by applying the heated composition to the medium M, said composition will solidify or reach a hardened state just as soon as it is cool. Therefore, after applying the heated composition to the placed in position medium M, it is only necessary to wait until they material'has cooled, at which time the same has assumed a solid state.

By heating the composition, said composition is softened so that it may be readily worked with a squeegee, or other element, and passed through the stencil; upon cooling, the composition solidifies and thereafter, maintains its proper form or shape. No drying by heat, or otherwise, is necessary because excessive'moisture is removed from the composition by the heating and prior to its application to the medium. Thus, it is not necesary to wait while excess moisture is evaporated through a drying step after the composition is applied to the medium because as soon as the composition cocls,-it has assumed its solid and dry state. This is a big advantage over previous methods which have been employed in forming Prior to the present invensemi-plastic nature when cool and the cold composition has been applied to the medium M.

In order to maintain a cold composition in a plastic state, said composition must contain excessive moisture and before the composition may assume a solid, dry state, such excessive moisture must be removed either by evaporation, which of course'is encouraged by a heating or drying step, or by'some other means. To aid in removing this excessive moisture from the cold composition after its application to the medium, it has been the practice to employ tissue, or other absorbent material, for. absorbing the excessive moisture out of the plastic material after the same had been applied to the medium, whereby the drying out of the composition is facilitated. With the present invention, the use of any absorbent material or backing in combination with the plastic material is not necessary for the heat, prior to application of the composition to the medium, takes out all the excess moisture and as soon as the material cools, it assumes its solid state.

In order to prevent the composition which is applied to the medium, from sticking or adhering to the top of the table, said top may be suitably coated or moistened to prevent this condition; or, if desired, a suitable backing paper may be interposed between the medium and-the table top so as to prevent the composition from passing through the medium and onto said top. In such instance, after the medium is removed from the table and suspended for cooling, the backing paper, indicated at 53 in Figure 6, may be removed. However, it is noted that the use of a backing material is only for the purpose of preventing the composition from adhering to the table top and is not essential to the present in vention.

The coils ll which are disposed immediately beneath the troughs 3B are sufllcient not only to heat said troughs but also to heat the metallic stencil 42.- Such heating of the stencil is accomplished through the heat exchange between the material or which the trough is constructed and the stencil. In some cases, it might be necessary to provide an auxiliary heating unit in order to assure that the stencil 42 is maintained at a predetermined temperature and for this purpose a heating unit 54 may be mounted as shown in Figure 8. This heating unit includes a curved supporting member 55 which is mounted beneath the transverse bar l5 and which is secured to the supports it by means of bars 55. A refractory block 51 is mounted within the member 55 and has a plurality of heating coils 58 therein. Due to the position of the heating unit 5|, it will be manifest that when the stencil carrier A is moved to its uppermost position, the stencil 42 is disposed immediately below. the heating unit, whereby said stencil is heated while in its raised position. By maintaining the stencil at a predetermined temperature, the heated composition C may be readily worked and also its passage through the stencil 42 is facilitated. As above pointed out, the use of the heating unit 54 is optional and is not essential to the invention.

The foregoing description of the invention is explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What I claim and desire to secure by Letters Patent is:

1. In an apparatus for producing display characters including, a support for a medium, a movable stencil carrier adapted to be moved over the support and medium, a stencil mounted in the assasoa carrier andarranged to be positioned over the mediumonthesupportwhenthscarrierisdisposed over the support. whereby a composition may be passed through the stencil and onto the medium to form characters thereon, and heating means associated with the carrier for heating the composition so that said composition may be applied to the medium while in a heated state. '2. In an apparatus for producing display characters including, a support for a medium, a stencil movable over the support and medium and arranged to be moved into engagement with the medium, means at one side of the stencil for receiving a composition whichis adapted to be passed throughthe stencil and onto the medium when said stencil is positioned thereover, whereby characters are formed on the medium, and means for heating said composition prior to its passage through the stencil.

3. In an apparatus for producing display characters including, a support for a medium, a'stencil movable over the support and medium and arranged to be moved downwardly onto the medium, means at one side of the stencil for receiving a composition which is adapted to be passed through the stencil and onto the medium when said stencil is in a lowered position, whereby characters are formed on the medium, and heating means associated with the stencil for heating the composition thereon and also for heating the stencil, whereby the composition may be applied to the medium while in a heated state.

4. In an apparatus for producing display characters including, a support for a medium, a stencil movable vertically over the support and medium and arranged to be moved downwardly onto the medium, means at one side of the stencil for receiving a composition which is adapted to be passed through the stencil and onto the me-v dium when said stencil is in a lowered position, whereby characters are formed on the medium, means for heating said composition prior to its passage through the stencil, and spring-pressed hold-down means carried by the stencil and adapted to engage the medium when the stencil is in a lowered position to hold said medium against movement on the support.

5. In an apparatus for producing display characters-including, a support for a medium, a stencil movable vertically over the support and medium and arranged tobe moved downwardly onto the medium, means at one side of the stencil for receiving a composition which is adapted to be passed through the stencil and onto the mea movement on the support, the holddown means being constructed so as to remain engaged with the medium for a predetermined time after the stencil is raised from the medium, whereby separation of the stencil and medium is assured.

6. In .an apparatus for producing display characters including, a support for a medium, a stencil movable vertically over the support and medium and arranged to be moved downwardly onto the medium, power driven mechanism for reciprocating the stencil to raise and lower the same, means at one side of the stencil for receiving a composition which is adapted to be passed through the stencil and onto the medium when said stencil is in a lowered position, acters are formed on the medium, heating said composition prior through the stencil.

7. In an apparatus for producing display characters including, a support for a medium, a stencil movable vertically over the support and medium and arranged to be moved downwardly onto the medium, means at one side of the stencil for receiving a composition which is adapted to be passed through the stencil and onto the medium when said stencil is in a lowered position, whereby characters are formed on the medium, heating means associated with the stencil for heating the composition thereon and also for heating the stencil, whereby th composition may be applied to the medium while in a heated state, and auxiliary heating means separate from the stencil and disposed thereabove for heating the stencil when the same is in a raised position.

8. As a sub-combination in an apparatus for whereby charand means for to its passage forming display characters, a stencil carrier including, a frame, a stencil mounted in said frame, a receptacle formed at one side of the frame for receiving a composition adapted to be passed through the stencil, and heating means mounted beneath the receptacle for heating the composition thereon.

9. As asub-combination in an apparatus for forming display characters, a stencil carrier including, a frame, a stencil mounted in said frame, a receptacle formed at one side of the frame for receiving a composition adapted to be passed through the stencil, heating means mounted beneath the receptacle for heating the composition therein, spring-pressed bars mounted on each side of the frame, and hold-down elements secured to the bars and extending beneath the stencil, said bars and elements being normally held in a plane below the bottom Of the stencil carrier frame and stencil.

JOHN H. POLLARJ).

Images