Methods for preventing warping of knitting and warping boards during hardening

Description

The drum becomes unusable for certain machines. To avoid these difficulties, it is necessary to machine the side surfaces of the typewheels with extraordinarily high precision, which is obviously very expensive. From DT-AS 1149 931, it is known to clamp the type wheels on the shaft using discs whose surfaces are machined to form a kind of "universal joint" so that the pressure exerted by the wing nuts is better distributed across the side surfaces of the type wheels. However, this does not eliminate the bending stresses and deformations caused by the non-parallelism of the type wheel side surfaces. In practice, attempts are made to compensate for these differences by inserting thin lamellae between the type wheels in certain areas, but this method is not efficient. The object of the invention is to create a type drum of the type specified above in which irregularities in the shape of the individual type wheels have no influence on the alignment of the types in the axial, radial and circumferential directions. According to the invention, this problem is solved by each typewheel having a number of adjusting parts which are attached at uniform intervals around the shaft on one side of the typewheel and project inwards over its central bore in such a way that they each partially engage in an annular groove and form a clamping connection with it. The invention is based on the principle of separately mounting the typewheels on the supporting shaft using the annular grooves provided on the shaft. The axial alignment is determined by the position of the annular grooves and by the individual adjustment elements of each typewheel, so that a deviation in thickness or other irregularities of one typewheel has no effect on the other typewheels. Existing tolerances therefore cannot accumulate over the entire length of the drum. The angular position of each typewheel can also be adjusted without affecting the adjustment of the other typewheels. Finally, this assembly avoids the mechanical stresses that, in the case of insufficient parallelism of the type faces, can cause warping of the type drum.Although a larger number of assembly parts are required for the type drum, the overall manufacturing cost is significantly reduced because the machining of the assembly parts does not require high precision, and, most importantly, the previously required precision in machining the type wheels themselves is eliminated. Despite the reduced precision, the type drums designed according to the invention meet the strictest requirements for high-quality type drums. Embodiments and advantageous further developments of the invention are characterized in the dependent claims. The invention is described below by way of example with reference to the drawing. The drawing shows... Fig. 1 is a schematic representation of the main components of a drum printing press equipped with a complete type drum. Fig. 2 shows a schematic representation of various cases of mounting typewheels on a drum shaft which is provided with setting grooves for the typewheels. Fig. 3 is a sectional view along line 5-5 of Fig. 4. Figs. 4A and 4B show an embodiment of adjusting parts for typewheels which can be inserted into the grooves of a drum shaft. Fig. 5, 6 and 7 other forms of adjusting parts of typewheels, Fig. 8 shows a section through a drum with devices for quickly attaching or removing typewheels on a shaft along line 8-8 in Fig. 9. Fig. 9 a cut along line 9-9 in Fig. 8, Fig. 10 shows an end view of the shaft of a drum with adjusting parts that can be inserted into grooves which are provided in the type wheels, according to line 10-10 in Fig. 11 and Fig. 11 shows a section along line 11-11 of Fig. 10. The schematic drawing in Fig. 1 shows the main components of a drum printing press. This includes a type drum 10 with a shaft 11 rotatably mounted in two bearings 12 and 13. One end of the shaft is coupled to a drive motor 14, and the other end of the shaft is mechanically coupled to a known type synchronizing generator 15, which provides the storage and comparator 16 with information about the angular position of the type rows of the drum's type wheels in front of the hammers of the stop mechanism 17. The hammer actuation mechanisms are operated by means of information supplied to them in a manner known per se via the storage and comparator 16. A sheet or strip of paper 18 with an ink ribbon 19 is arranged between the type drum and the hammers of the stop mechanism to receive the printed characters.This design is found in a very large number of printing presses, in which the type drum either consists of a one-piece cylinder provided with engraved type series arranged on its circumference in a known manner, or in which the type drum consists of stacked type wheels which are mounted on the shaft and pressed against each other between two disks 21 and 22 by means of nuts 23 and 24 screwed onto the shaft. Figures 2 and 3 show, in summary form, various embodiments of typewheels mounted on a type drum shaft with devices corresponding to the first embodiment of the invention, i.e., with the aid of adjusting elements that are attached around the shaft on one side of each typewheel and engage at least partially without play in an annular groove provided in the drum shaft. Figure 2 shows three different types of typewheels mounted on the same shaft 50. A typewheel 51 shown in half-section is a simple typewheel provided with a single row of types 52 distributed around its circumference and arranged such that the central axis of the types lies in a plane X, which is substantially in the middle of the thickness dimension of the typewheel. Typewheels of this type can be mounted not only with the fastening means shown in Figure 2, but also in the manner shown in Figure 3.1 shows how to form type drums by stacking type wheels on top of each other. a shaft. The typewheel 55 is a "helical" typewheel on which types are engraved in relief and arranged along a helix whose pitch P is equal to the distance between the printing columns along a line. Typewheels of this type can be used on printing presses either with a single typewheel or with several typewheels mounted on a drum, printing the same line in parallel. As already mentioned, these typewheels require continuous transverse movement of the paper (or the typewheel) during the printing of a line. The typewheel 60 is a multiple typewheel, consisting either of a group of typewheels or a block of typewheels, on which three parallel rows of type 61, 62, and 63 are mounted. Due to its design, these rows can be offset from one another to a greater or lesser extent in the direction of rotation of the drum.It was found that it is advantageous to manufacture typewheels of this type in which several type rows are formed simultaneously in parallel to each other. The section shown in Fig. 2. The drum shaft 50 has an outer diameter D, which is precisely machined to accommodate the typewheels. The bore of the typewheels is adapted to this diameter and lies exactly concentrically to the axis of rotation V-W of the shaft. Adjustment grooves 42, 43, and 44 of width E are provided in the shaft at intervals determined according to the longitudinal position of the typewheels and their method of attachment to the shaft. Each groove has two opposing side surfaces 33 and 34, each of which lies in principle in a plane perpendicular to the drum axis. They are cut down to a diameter d, allowing sufficient engagement of the adjusting elements in the grooves. On the side surface 48 of the typewheel 51, three adjusting elements 45, 46, and 47 are arranged (Fig. 3) at an angle of 120° to each other around the shaft 50 and fastened to the typewheel by means of fastening screws 56, 57, and 58, respectively.These adjusting elements are round discs made of metal, hard plastic, or any other suitable material, which partially engage in an adjusting groove 42 and whose thickness is dimensioned according to the width of the grooves. Under these conditions, the typewheel 51 is precisely adjusted on the shaft 50 and in relation to the other typewheels mounted on the same shaft. This method of mounting the typewheels on the shaft also allows for a very lightweight construction of a type drum with spaced typewheels, offering certain advantages over previously used methods. With the described assembly, it is no longer necessary to provide intermediate rings between the typewheels. At the ends of the drum, the parts required to lock the typewheels on the shaft are also eliminated, as is any resulting bending stress on the shaft.The machining of the typewheel faces and the formation of the typewheel bore are simplified because precise parallelism of the typewheel faces is no longer necessary. The angular position of the typewheels on the shaft is generally determined by design using two longitudinal keys 53 and 54 (Fig. 3), which engage partly in longitudinal grooves in the shaft and partly in grooves in the typewheels. However, in many cases it is advantageous to allow, at least during machine setup, a slight adjustment of the angular position of certain typewheels on the drive shaft in one direction or the other by moving their adjusting elements in their grooves. This corrects differences in the alignment of the printed characters printed by different typewheels on the same line. For this purpose, each typewheel is provided, for example, with one or more notches 25, 26.the types are arranged between the type wheels on the circumference of the type wheel in such a way that they can accommodate keys which can exert the force required to rotate each type wheel on its shaft. Each type wheel can be provided with an additional locking system, for example, the locking system shown in Fig. 2, which consists of a screw 27 inserted into a threaded bore 29 and pressing on a bronze cylinder 28, which secures the type wheel on the drum shaft in a final position. It will be seen later that the use of adjusting elements with a certain elasticity in the grooves makes it possible to do without these locking devices to a certain extent. A type wheel 55 (Fig. 2) with a helical distribution of the types can be mounted on the shaft 50 in the same way as the type wheel 51. The typewheel 60 is a typewheel block or multiple typewheel with several straight and parallel rows of type, each of which is intended for a printing column. Typewheels of this type are frequently used to form a complete drum with adjoining typewheels of the type shown in Fig. 1 by stacking them on a shaft, or to form a drum with a reduced number of typewheels, which is used in conjunction with a mechanism for a transverse movement of the paper in a known manner. The typewheel 60 shown in Fig. 2 can be provided with a recess 59 which receives the adjusting elements of an adjacent typewheel and their fastening screws. In the arrangement of Fig. 2, the adjusting elements of the typewheel 60 lie in a recess 64, and they are inserted into a groove 44 of the support shaft.When applying this measure, the adjusting parts of a type wheel arranged at the end of a drum do not protrude beyond the type wheel, making it possible to form drums by means of joined elements whose longitudinal dimension is reduced so that they can be used in place of one-piece drums (engraved cylinders). The adjusting parts used for adjusting the typewheels on a drum shaft can, of course, be manufactured with great precision so that they engage in grooves that are also machined with great precision. However, Figures 4A and 4B show in detail an embodiment of adjusting parts which has certain advantages. These adjusting parts can be used to fasten typewheels on a shaft of the type shown in Figures 2 and 3, but require less machining precision. An adjusting part 65 (Figures 4A and 4B) consists of a round metal disc with a diameter 0, which is provided with a central opening 66 for the passage of a fastening screw. The diameter 0 is dimensioned such that a part of the disc, after its fastening to a The side surface of a typewheel engages in an adjustment groove (Fig. 3). The side surfaces 68 and 69 of the disc are flat and not parallel, so that the thickness of the disc in its thinnest part has a value Fi that is less than the width of the adjustment grooves, while the opposite part has a thickness Fi that is slightly greater than the width of the grooves. It is advantageous to provide the thickest or thinnest part of each disc with an engraved marking 78, which facilitates alignment during assembly. The central section of the side surface 69 of the disc is provided with a flattened area 77, the surface of which is parallel to the other surface of the disc, so that the fastening screws can be properly clamped by the head of the fastening screw bearing against this flattened area.It is understood that adjusting parts of this type do not require great accuracy in machining, reduce the precision required for machining the adjusting grooves, and, if desired, allow for a more or less strong braking action of the typewheels on their carrier shaft, so that the angular position of the typewheels on the shaft can be corrected as previously described, or even a fairly strong locking action is possible, thus making the use of other locking devices for the typewheels unnecessary. After the adjusting washers of a typewheel have been fitted in the manner shown in Fig. 3, with the thinnest part of each washer inserted into the corresponding adjusting groove and the clamping screws 56, 57, and 58 not yet tightened against the washers, the pins 74 and 75 of a pin wrench 73 are inserted into two accessible holes of the three holes 70, 71, and 72 (Fig. 4A) provided in a washer 45.The pin wrench 73 (Fig. 3) is turned in the direction of arrow F so that a thicker section of the washer is inserted into the slot until a clearly discernible clamping action is achieved. The screw 56 is then tightened using a wrench 76 or, if accessible, a screwdriver inserted into the slot of the screw head. While tightening the screw, the washer 45 can be held in place to prevent it from rotating and causing excessive locking in the slot, if moderate clamping is desired. It is evident that the progressively thicker section of the washer can also take the form of a helical ramp distributed around the entire circumference of the washer, or any other suitable shape.Furthermore, it is evident that in the case where the adjusting parts are included inside a type wheel, tools of a suitable shape will be used for their fastening. Figures 5, 6 and 7 show other embodiments of simplified adjustment parts which can also be manufactured with relatively low accuracy. Part 80 (Fig. 5) is cut from a metal strip of width L, the thickness of which is generally much smaller than the width of fine adjustment grooves. Part 80 is cut at its ends with a radius of curvature R that corresponds almost exactly to the radius of curvature R at the bottom of a groove 89 of the shaft 50. Part 80 is provided with a hole 81 whose diameter is slightly larger than the diameter of a fastening screw 82. Part 80 is provided with a curvature 83 that gives the sections 84 of this part a thickness considerably greater than the width of the groove. Fig. 7 shows the insertion of part 80 into an adjustment groove 89. The sections 84 of the part are first inserted into the groove 89, and a screw 82 is inserted into the hole 81 of the part and then screwed to the wheel 85 (Fig. 6) and tightened. The shape and position of sections 84 of part 80 in the groove 89 (F i g.5) prevent this part from twisting while the screw 82 is tightened. Depending on the curvature 83 of the part originally given size, the section inserted into the groove 89 will be more or less affected during the tightening of the screw 86. less stretched, it rests against the opposing side surfaces of the groove. The force exerted on the walls of the groove is limited by the thickness and flexibility of the metal strip forming part 80, since this part is more easily stretched the thinner it is. An analogous adjustment of a wheel can be achieved with correspondingly curved parts of square or rectangular shape, or even with round metal discs 86 (Fig. 5), which are likewise curved at point 83. In the latter case, however, it is necessary to prevent the disc from rotating when the fastening screw is tightened. Figs. 8 and 9 show an embodiment of the invention designed to allow quick attachment or removal of the type wheels from the drum shaft. In this case, the shaft 100 is provided with adjusting grooves 97 and 98, which are suitable for receiving the adjusting parts, as well as with longitudinal grooves 101, 102 and 103.The adjusting elements consist, for example, of flat and slightly conical round discs 90, 91, and 92 for the typewheel 93, the discs also being slightly elastic in their thickness direction, similar to spring washer discs. These discs, which are fastened to the typewheel 93 by means of fastening screws 94, 95, and 96, can first be fitted to the typewheels, which are then mounted on the shaft as shown in Figures 8 and 9 and then rotated by means of wrenches inserted into the notches 104 and 105 or by any other suitable means so that the adjusting elements are moved from position A to position B, which is close to the final locking position for the typewheel on the carrier shaft. During this movement, the adjusting elements are inserted into the adjusting grooves.Then the angular position of the typewheels on the shaft is precisely adjusted, and the typewheels are each fixed on the shaft by means of a locking screw 106, which is inserted into a threaded bore 107 and presses a locking finger 108 against the shaft. The second embodiment of the invention is particularly suitable for mounting individual typewheels directly adjacent to one another on the same shaft. In this case, adjusting grooves are provided in the typewheels, and the adjusting elements that can be inserted into these grooves are firmly connected to the shaft. In the embodiment shown in Figures 10 and 11, a shaft HO is provided with longitudinal grooves 111, 112 and 113, into which a comb 114, 115 and 116 respectively is inserted, each comb being provided with teeth 120... 125. At each end of the drum shaft, each comb is driven onto the shaft at its ends by means of discs 129. 509587 / 160 centered, one of which is provided at each end and is held in place by nuts 126 and 127. The typewheel 130 (Fig. 11), like every other typewheel mounted on this shaft, is provided with an annular groove 131 and with recesses 132, 133, and 134 for the insertion of the teeth 120...125 of the combs into the annular grooves of the typewheels. In the sectional view of Fig. 11, the teeth 121, 122, 123, 124, and 125 are shown after their insertion into the setting grooves of the typewheels 141...145, while the first teeth 120 of the combs 114, 115, and 116 are not yet in the annular groove. 10 The teeth 131 of the typewheel 130 are inserted, which has not yet been rotated around the shaft. After the teeth are inserted into the groove, each typewheel can be fixed on the shaft by means of a locking screw 150, which pushes a piston 151 inwards that engages a brake shoe 152, which is located in the groove of the typewheel and rests against the shaft. The teeth can, of course, be replaced by steel pins inserted into blind holes provided in the shaft, thereby achieving an equivalent result. This includes 3 sheets of drawings

Claims

Patent claims:

1. Type drum for a printing press with several type wheels which are non-rotatably mounted along a rotating shaft, on which annular grooves are provided at intervals for determining the spacing of the type wheels on the shaft and with adjusting devices for the angular position of each type wheel, characterized in that each type wheel (51, 55, 60; 85; 93) has a number of adjusting parts (45, 46, 47; 65; 80; 90, 91, 92) which are attached at equal intervals around the shaft (50; 100) on one side of the type wheel and project inwards over its central bore in such a way that they each partially engage in an annular groove (42, 43, 44; 89; 97, 98) and form a clamping connection with it.

2. Type drum according to claim 1, characterized in that the adjusting devices for the angular position of each type wheel (51) are formed by an angular position marking (25, 26) and devices (27, 28; 106, 108) for rotationally fixed connection of each type wheel to the shaft (50; 100).

3. Type drum according to claim 1 or 2, characterized in that the shaft (100) has a number of longitudinal grooves (101, 102, 103) which are shaped and arranged in such a way as to make it possible to bring each type wheel close to an associated annular groove (97, 98) when the adjusting parts (90, 91, 92) have previously been attached to one side of the type wheel.

4. Type drum according to one of claims 1 to 3, characterized in that each adjusting part consists of a flat round disc (45, 46, 47) fastened by a screw (56, 57, 58), which is thick enough to be inserted clampingly into an annular groove (42, 43, 44) of the shaft. 5.Type drum according to one of claims 1 to 3, characterized in that each adjusting part consists of a disc (65) with non-parallel end faces, which can be locked by a screw and which is machined such that its smallest thickness (FX) is less than the width of an annular groove, while its largest thickness (F2) is at least equal to the width of an annular groove, so that a type wheel can be fixed on the shaft by inserting its adjusting discs with a section of small thickness into an annular groove of the shaft and then simultaneously with or before their fixing on the type wheel, rotating them around their axis by means of their fastening means in such a way that they are clamped in the annular groove.

6. Type drum according to one of claims 1 to 3, characterized in that each adjusting part is a plate (80) that can be locked by a screw (82), the thickness of which is less than the width of an annular groove (89) and which has a section (84) that can be inserted into an annular groove (89) and which is bent in such a way that, after insertion into the annular groove, it is clamped between the two side surfaces of the annular groove when the screw is tightened.

7. Type drum according to one of claims 4 to 6, characterized in that each type wheel (60) has a flange with a lesser thickness than a type wheel to which the adjusting parts (45, 46, 47) are attached and that the flange together with the type wheel forms a cavity (64) which serves to receive the adjusting parts (45, 46, 47) and their fastening means (56, 57, 58).

8. Type drum according to one of claims 4 to 6, characterized in that certain type wheels (60) have a flange with a lesser thickness than the type wheel, that the flange together with the type wheel forms two cavities (59, 64) and that one cavity (64) serves to receive the adjusting parts (45, 46, 47) and their fastening means (56, 57, 58) of the type wheel (60) and the other cavity (59) serves to receive the adjusting parts (45, 46, 47) and their fastening means (56, 57, 58) attached to the adjacent type wheel (55). The invention relates to a type drum for a printing press with several type wheels which are non-rotatably mounted along a rotating shaft, on which annular grooves are provided at intervals to determine the spacing of the type wheels on the shaft and with adjusting devices for the angular position of each type wheel. Type drums of this type, known for example from US Patent 3179 044, have the advantage over solid type drums that if individual types are damaged, the entire drum does not have to be discarded, but only individual type wheels need to be replaced. On the other hand, assembling individual typewheels into a drum presents a number of problems. In particular, the axial distances of the typewheels and their angular positions on the common axis must be set very precisely to ensure flawless impressions in the printing lines (circumferential adjustment) and printing columns (axial adjustment). Furthermore, the end faces of the type that cause the impression must lie exactly on a cylindrical surface that is precisely coaxial with the drum axis to ensure uniform impressions (radial adjustment). If the type drum is formed by stacking and clamping the typewheels on a common shaft, the above conditions can only be met with very precise machining, and even then only approximately. A typical type drum consists of more than one hundred typewheels. Differences in the thickness of the typewheels on the order of one-hundredth of a millimeter can add up to a total difference on the order of one millimeter across the entire length of the drum, making it practically impossible to align the outermost typewheels of the drum with the corresponding impression spaces. Furthermore, slight differences in the parallelism of the side surfaces of the typewheels, when clamped to the shaft, can cause deformation of the shaft through longitudinal bending, i.e., curvature of the drum, which can even be observed in drums that have a large support shaft. diameters included. This curvature can cause an eccentricity of the middle section of the drum relative to its end sections, which can be so pronounced that the