US3388659A - Bed and cylinder printing mechanism with adjustable anvil - Google Patents

Description

June 18, 1968 YOW-JIUN HU 3,338,659

BED AND CYLINDER PRINTING MECHANISM WITH ADJUSTABLE ANVIL Filed March 10, 1965 5 Sheets-She et l .mvzmon Yow- J/un Hu ATTORNEY June 18, 1968 YOW-JIUN HU 3,388,659

BED AND CYLINDER PRINTING MECHANISM WITH ADJUSTABLE ANVIL 5 Sfieets-Sheet 2 Filed March 10, 1965 June 18, 1968 YOW-JIUN HU 3,388,659

BED AND CYLINDER PRINTING MECHANISM WITH ADJUSTABLE ANVIL Filed March 10, 1965 5 Sheets-Sheet 5 United States Patent 3,388,659 BED AND CYLINDER PRINTING MECHANISM WiTH ADJUSTABLE ANVIL Yow-Jiun Hu, Alexandria, Va., assignor to Farriugton Business Machines Corporation, Springfield, Va., a corporation of Massachusetts Filed Mar. 10, 1965, Ser. No. 433,-l85 2 Claims. (Cl. 101-269) ABSTRACT OF THE DISCLOSURE An apparatus in a printing machine utilizing portable printing plates. A printing bed upon which the printing plate is seated to obtain optimum printing pressure when the platen of the printing machine is pressed against a document overlying the printing plate. The printing bed is in the form of an anvil and is adjusted to accommodate the particular printing plate and/ or document thickness employed for a printing operation. A sensing finger determines the thickness of the printing plate while seated on the anvil in accordance with the thickness thus sensed. The sensing finger causes a spacer to be moved which spacer indirectly causes the anvil to be adjusted.

The present invention relates to a printing device and, more particularly, to an improved printing device for recording data on sales slip documents or the like by means of printing plates, having raised type characters thereon, of a kind suitable for use as identification tokens and adapted to be carried by individual customers.

In printing devices of the variety disclosed above, it is well known that in order to obtain a uniform and clear imprint, the printing pressure should be maintained as much near a fixed value as possible. In imprinters of the type where the shaft or other means carrying the platen is constrained to reciprocating movement within a predetermined path, the upper portion of which defines a plane over the printing bed area, a constant printing pressure reference gap will exist between the aforementioned plane and the printing bed surface. Such a printing pressure reference gap can readily be set to accommodate a printing plate and document of pre-estimated fixed thicknesses, by employing shimming techniques in the platen assembly or in the printing bed to widen or narrow the printing pressure reference gap for obtaining the proper printing pressure. However, it has been found that in actual practice that printing plates and/ or sales slip documents having a wide range of thicknesses are utilized. Since mechanical limitations and the necessity for expending considerable time make it quite impractical to measure thickness variances of the printing plate and/or document for each transaction and accordingly shim the imprinter to adjust the printing reference gap, the resultant printing pressure applied will vary to the extent that on many occurrences a uniform and clear imprint will not be obtained.

The general purpose of this invention. is to provide an improved printing device which overcomes the aforeescribed disadvantages by automatically providing a constant printing pressure for printing plates and/ or documents of varying thicknesses. To attain this, the present invention contemplates a unique anvil assembly which senses the thickness of the printing plate and/or document for each imprint cycle and automatically provides a related adjustment or compensation of the printing reference gap in the printing device to produce an optimum printing pressure.

An object of the present invention is the provision of a device which produces clean cut and uniform imprinting.

Another object of the present invention is to provide a Patented June 18, 1968 substantially uniform printing pressure for printing plates and/ or documents of varying thicknesses.

A further object of the present invention is the provision of an automatic device for sensing and compensating for varying printing plate and/ or document thicknesses to provide substantially uniform printing pressure.

Other objects, advantages, and capabilities of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, illustrating preferred embodiments of the invention.

In the drawings:

FIGURE 1 is a front perspeetvie view of an imprinter which may 'be used with the present invention.

FIGURE 2 is a perspective view of an embodiment of the present invention.

FIGURES 3 and 4 are cross-sectional views, taken on line 3-3 in FIGURE 2, showing certain positions taken by the elements of the compensating assembly as the printing device is operated.

FIGURE 5 is a cross-sectional view, taken on line 33 in FIGURE 2, but disclosing a further manner of providing complementary surfaces between anvil 14 and wedge block 27.

FIGURE 6 is a perspective view of another embodiment of the present invention.

In FIGURE 1 there is shown an imprinter having a pair of C-frame members 11 and 12, each being in parallel relationship with the other, yet spaced by a base member 13, there being located on the base member an anvil 14 which surface defines the plane of a printing bed. On

each side and parallel to the printing bed is located one of a pair of guide rails 15 and 16, the guide rails being fastened at their ends to the upper portion of the respective C-frame members by suitable means (not shown). The inner sides of the guide rails 15 and 16 are each channeled to define a pair of paths 17 and 18 respectively, for guiding the bearings 19. The bearings are employed to guide a platen head assembly, generally referred to as 21, comprising a bracketed handle 20 and platen 22 on shaft 23. The platen head assembly is directed over the anvil 14 for imprinting upon a document 24 disposed over the upwardly presented face of a printing plate 25 hearing raised type characters thereon, by exerting pressure on the same.

There is illustrated in FIGURES 2 and 3 the base 13 provided with a cavity 26 wherein is seated a wedge block 27 and the anvil 14 overlying the wedge block. Wedge block 27, like anvil 14, is closely fitted in the cavity to prevent movement to the right or left as viewed along the longitudinal axis of FIGURE 1; however, ample space is allowed for, so that only the wedge block may slide on the cavity base in either of the opposite directions indicated by the numeral 28. Anvil 14 is therefore so enclosed as to be restricted only to vertical movement in the cavity. The upper surface of wedge block 27 and the lower surface of anvil 14 are so designed that each of the aforesaid surfaces is made to be complementary with the other. Furthermore, each of the above-mentioned surfaces is smoothly finished in a suitable manner to allow for minimum friction and maximum sliding action between the two surfaces. The upper surface of anvil 14- is adapted to support the printing plate 25, and at least a portion of a document 24.

An L-like'shaped arm 29 is situated for pivotal movement about the pivot member 31 which is fixedly attached to the base 13 and acts a a reference piece. At one end of the arm 29 is a small elongated aperature 32 for loosely receiving a rod 33 therein, the rod 33 being secured to a spacer 34 adapted for sliding vertical movement restricted by the guide rails 35 within a cut-out 35 located in the front side wall 37 of the base 13. It is observed that the exterior 34' of spacer 34 is adapted to be complementary with exterior 27 of wedge block 27 for flush engagement therewith, whereby the exteriors are provided to have maximum friction for minimizing sliding with one another. At the remaining end of arm 29 and integral therewith is a cross bar 38 each terminal portion of which serves a separate purpose. The right hand terminal contains an adjustable sensor screw 39 having a flat-shaped lower end 41 overlying a portion of the document 24 and printing plate 25. The left hand terminal is provided with an angled bar 42 so positioned to engage either with the platen roller 22, shaft 23, or some other portion of the platen read assembly 21 only when the platen head assembly lies in its ready-to-imprint position, as illustrated in FIGURE 1. A pair of compression springs 43 mounted on screws 44 are furnished to normally maintain the wedge block 27 in a biased position toward the rear of cavity 26.

In operation, assume that the imprinter being employed is of the unidirectional type, that is effecting an imprint when directed in only one direction such as that indicated by the arrow X in FIGURE 1. When the platen roller 22 is returned to the left side of the imprinter for a ready-toimprint operation, the platen roller 22 or its shaft 23 will engage the angled bar 42 to rock the arm 29 in a counterclockwise direction about pivot member 31 and thus displace the lower end 41 of sensor screw 39 from the upper surface of anvil 14, allowing a printing plate 25 and document 24 to be readily positioned therebetween upon the the anvil 14. Simultaneously, with the rocking of arm 29,

spacer 34 will be raised to its uppermost vertical position,

as shown in FIGURE 3, due to its linkage with arm 29. As the platen roller is thereafter directed in the X direction to accomplish an imprint, the arm 29 will then rotate in the clockwise direction, due to the weight of spacer 34, sensor screw 39 and unbalanced arm 29, until the flat surface 41 of sensor screw 39 abuts the document 24 overlying the printing plate 25 and anvil 14. The termination of the clockwise rotation of arm 29 results in the lowering of spacer 34 a distance proportional to combined thicknesses of the document 24 and printing plate 25. As the platen roller 22 traverses the area over anvil 14, it will then press the document, card and anvil 14 downwardly, whereby the anvil 14 will in turn slideably force wedge block 27 horizontally toward the front side wall 37 until it abuts the spacer 34 as illustrated in FIGURE 4. The complementary angles between anvil 14-wedge block 27 and wedge block 27spacer 34, and the movement of spacer 34 relative to reference piece 31, are so designed that the vertical positioning of the anvil 14 surface (printing bed plane) during the printing action is displaced by an amount substantially equal to the combined thickness of the specific printing plate and document to be employed as sensed by the sensor screw 39, thereby providing an optimum imprint. The system therefor automatically regulates the printing reference gap, between the plane of the printing bed and the upper plane defined by the travel of the platen shaft, to compensate for varying thicknesses of printing plates and/or documents to maintain a constant and optimum printing pressure.

It will be appreciated that, if desired, the embodiment disclosed in FIGURE 1 could easily be modified to allow the device to function as a bidirectional type imprinter by providing a similar sensing assembly on the right hand side of the imprinter along the right longitudinal axis of FIGURE 1, and connecting it to compensating spacer 34. It is also quite apparent that the bar 42 could be eliminated whereby the sensor screw 39 could be raised merely by insertion of a card and/or document between the sensor and the anvil. Furthermore, the printing bed could also be designed for allowing only the document or the printing plate to lie beneath the sensor screw 39.

FIGURE illustrates a further manner of providing complementary surfaces between anvil 14 and wedge block 27, to achieve not only an improved sliding factor, but also a greater vertical movement of the anvil relative to the smaller horizontal movement of the wedge block, thus enabling a smaller cavity area within the base to be utilized.

Another embodiment of the present invention is disclosed in FIGURE 6 wherein there is shown a pair of brackets 45 having curved lips fixedly attached to base 13. The underside surfaces 46 of brackets 45 are employed as reference points for reasons which will become apparent hereinafter. The spacer 34 is biased in a downward direction by an expansion spring 47, and positioned directly under the spacer 34 is a common support 50 of the terminal portions of a pair of armlike members 48 and 49, the latter being respectively rockable about a pair of pivot points 51 and 52. The armlike members 48, 49 have mutual angle bars 53 and 54 attached thereto, which bars are so positioned to engage either the platen roller 22, shaft 23, or some other portion of the platen head assembly 21 only when the platen head assembly lies in its ready-to-irnprint position. Again, the pair of compression springs 43 mounted on screws 44 are employed to normally maintain the wedge block 27 in a biased position toward the rear of the cavity 26.

In operation, assume the platen 22 is on the extreme right hand side of the printing device in a ready-to-imprint position in which case angle bar 54 is acted upon to rock armlike member 49 about pivot point 52 in a clockwise direction thus lifting spacer 34 in its uppermost vertical position against the force of expansion spring 47. The printing plate is then inserted between the surface of anvil 14 (printing bed) and the underside surfaces 46 of bracket 45, thereby urging the anvil 14 downwardly in accordance with the thickness of the printing plate to force wedge block 27 toward the front side wall 37. Document 24 is then placed over the printing plate and motion is imparted to the platen 22 for moving the same toward the printing bed area at which time angle bar 54 is disengaged allowing the off-center weight of armlike member 49 and force of expansion spring 47 to rock the arm in a counterclockwise direction enabling spacer 34 to fall between the front side wall 37 and wedge block 27 for maintaining the latter and thus anvil 14 in a fixed position when the platen 22 is traversing the printing bed causing an imprint to be formed on the document. As the platen 22 is moved to the extreme left of the printing device, angle bar 53 will be engaged to again lift spacer 34 for compensating purposes during a subsequent printing operation when a new document and printing plate are used.

The reference points, underside surfaces 46, are therefore utilized to regulate the plane of the printing bed (surface of anvil 14) in accordance with the particular thickness of the printing plate to be employed in any one printing operation. The instant embodiment illustrates the use of a compensating anvil for bidirectional printing devices, by adjusting only for the thickness of the printing plate for use in those instances where the document thickness remains constant. It is noted that the instant embodiment may be preferred for those cases where it is desirable to have a slight increase in the printing pressure applied when the number of documents being imprinted upon is unusually large. Obviously, the embodiment shown in FIG- URE 6 could he modified to compensate for the combined thickness of a printing plate and document or for a document only.

It should be understood, of course, that the foregoing disclosure relates to only a preferred embodiment of the invention and that numerous modifications or alternations may be made therein without departing from the spirit and the scope of the invention. It is desired, therefore, that only such limitations be placed on the invention as are imposed by the prior art and as set forth in the appended claims.

What is claimed:

1. In the art of printing machines of the type adapted to use portable printing plates, a machine comprising a base, a platen, a wedge adapted for horizontal movement within a single path on said base, a resilient member biasing said wedge against such a movement, adjustable spacer means adapted for engagement with said wedge for limiting the movement of said wedge when urged against said resilient member, an anvil overlying the wedge and adapted for proportional vertical movement relative to the base in response to the horizontal movement of said wedge, the surface of the anvil defining a first plane adapted to support thereon in superimposed relation a printing plate and at least a portion of a document for pressure engagement with the platen, a shaft supporting said platen, means providing a fixed path to guide the shaft and thus the platen over the anvil, the path of travel by the upper surface of said shaft defining a second plane parallel to said first plane, sensing means for physically determining the combined thickness of a printing plate and document to be placed on the anvil relative to a reference point fixed to said base, means for connecting said spacer means with said sensing means for relative movement 20 therewith to adjust the position of the spacer means in accordance with the said thickness sensed, the platen adapted when pressing against a document and printing plate to force said anvil downwardly thus moving the wedge horizontally against the resilient member until engagement is made with the spacer means to compensate the surface level of the anvil in accordance with the sensed thickness allowing an optimum printing pressure to be achieved.

2. In the art of printing machines according to claim 1 including means for elevating said sensing means from said anvil when the platen is in its initial rest position and for urging said sensing means toward said anvil when the platen has been moved from its initial rest position.

References Cited UNITED STATES PATENTS 764,096 7/ 1904 Williams 10l407 3,179,046 4/1965 Maul et al. 101--269 FOREIGN PATENTS 333,987 8/1930 Great Britain.

ROBERT E. PULFREY, Primary Examiner.

F. A. WINANS, Assistant Examiner.

Images