Patent GB-495841-A (GB)
Title: Improvements in or relating to enclosed fountains for rotary intaglio printing presses
IPC: B41F9/06
Filed: 1937-05-21
Abstract: 495,841. Printing-machines. WEISS, A. May 21, 1937, No. 14230. Convention date, May 23, 1936. [Class 100 (ii)] Inking-apparatus.-In a rotary intaglio printing-press having an enclosed ink housing and in which the printing-cylinder and an adjustable inking-head take part in sealing the ink housing from the outer atmosphere, the mechanism for adjusting the position of the inking-head is located outside the housing so as to prevent contamination of the adjusting- mechanism by vapours within the housing. The mechanism for operating the doctor blade, and that for adjusting sealing-members in the spaces between the ends of the printing- cylinder and end walls of the housing are also located outside the housing for the same purpose. The ink housing or fountain includes a sump 20 having side walls 21, 22, and a pipe 23 permits ink to be withdrawn by a pumping and re-circulating mechanism such as described in Specification 440,773. A side plate 26 adjustable vertically of the wall 21 and bearing against a lip 25 on a horizontal flange 24 thereof has a platform 27 to which four guide rods 28 are secured. The rods 28 are adapted to slide in guide members 34, 35, formed on a plate 29 extending across the housing and having a horizontal base 30 resting on the flange 24, and each rod has rack teeth engaged by a pinion on a horizontal shaft 39. The shaft 39 is also centrally supported in a bracket 41 secured to the plate 29, this bracket supporting a worm 46 which is engaged with a worm-wheel 47 on the shaft 39. Rotation of the worm shaft 45 by means of a handle results in the vertical movement of the platform 27 on which an inking-head 49 is supported. The plate 29 is pivoted to three stub shafts 33 mounted on the wall 21 whereby the entire inking-head can be swung away from the printing-cylinder 196. The inking-head 49 has a base 50 which is grooved to receive a flange 48 on the platform 27. The'head 49 is detachably held on the platform 27 by means of two cams each of which is rotated to engage a flanged roller mounted on the platform 27 to press the base 50 against the flange 48. When the head 49 is to be released, the cams are rotated through 180‹ to engage further rollers on the platform 27, so that the base 50 is moved away from the flange 48. The cams are secured to two rotatable stub shafts geared to a longitudinal rack bar 57 slidable within the inking-head 49, and in engagement with a gear-wheel 62 rotatable by means of a handle 61. A sealing-strip 74 and positioning-strip 76 are secured in a bracket 69 detachablv mounted on the head 49 and held in position by a spring-strip 70 which can be moved into and out of engagement with the bracket by cam and lever means actuated from the same stub shafts which effect the locking of the head 49. An ink manifold member 94 is secured within the inking-head 49 by means of bolts. Ink is supplied from a pipe 112 to a longitudinal chamber 111 which communicates with two further chambers. The latter chambers each communicate with two elbow members which feed the ink to ducts. These ducts supply the ink to a series of smaller ducts, so that the ink emerges from a nozzle 79 in the inking-head in a uniform stream. The manifold member is formed in a number of sections each having an outer lip coacting with a flanged portion on the inking-head to form the nozzle 79. Provision is made for draining the ink from the inking-head 49 before the latter is removed from the platform 27. A conduit 115 provided with a valve 116 allows communication between the ink supply chamber 111 and the interior of the ink fountain. The valve contains a rotatable valve plug which is geared to the stub shaft 60 on which the operating-handle 61 is mounted. Rotation of the handle 61 to release the inking- head 49 and sealing-strip bracket 69, also opens the valve 116 to byepass ink from the passage 111 to the ink fountain. The doctor supporting mechanism is mounted for vertical adjustment on the opposite side wall 22 of the ink fountain. An extension 121 of the wall 22 has pairs of spaced guides 123 to receive guide rods 125 which are formed with rack teeth engaged by pinions carried by a longitudinal shaft 128 journalled on the plate 121. The shaft 128 is rotatable through worm-gearing 133, 134 from the stub shaft 135, so that vertical adjustment of the guide rods 125 is effected. The rods 125 carry mounting-heads in which a shaft 140 is mounted about which the doctor means pivots. An arcshaped wall plate 141, formed with lugs pivoted on the shaft 140, has an extension 143 adapted to engage a flange 122 on the wall 121, and has lugs 144 to receive a rod 145, which in turn supports two brackets 146. The lower ends of the brackets 146 have bosses mounted on the shaft 140. An apron member 149 bolted to the brackets 146 is provided with a stub shaft 151 having a roller 152 which engages a cam groove in a collar 154 secured to the shaft 140, whereby rotation of the shaft 140 causes reciprocation of the apron 149. The apron carries a doctor holder 156 and flexible doctor 159. A sealing-blade 160 beneath the doctor, and exerting upward pressure thereon, is mounted on the plate 141. The sealing- blade extends to the edge of the doctor at the ends, but not where the doctor contacts the cylinder. The plate 141 and attached apron 149 may pivot about the shaft 140, but can be locked in operative position by gearoperated locking-pins operated by crank handles. A pressure blade 169 bears on the doctor 159, and is mounted on a cover 170 pivotally mounted on the apron 149 by means of links 171 which are pivoted by pins 172 to the apron and to the cover by pins 170a. The pressure blade is urged into operative position about the pins 170a by cams mounted on a shaft 176 carried by the cover 170 and engaging rollers 178 carried by the apron 149. The shaft 176 is rotated by means of worm-gearing 180, 181 operated from a knob 183. An adjustable arc-shaped indicator dial clamped to the shaft 176 is exposed through a window in the cover 170. This arrangement gives an indication of the pressure exerted by the blade 169 on the doctor. A stop means on the indicator dial warns the operator when the doctor is worn away to its limit, since the knob 183 cannot then be turned to apply further pressure to the doctor. The cover 170 can be swung away from the apron 149 when the pins 170a are moved axially. The pins 170a are operated through gearing by means of crank handles whereby the cover is released from the apron 149. The sides of the top ends of the ink fountain between the sealing-strip 74 on the inking-head 49 and the doctor 159 are sealed by a pair of arc-shaped plates 184, Fig. 8, upon which toothed sectors 185 are provided. A stub shaft 188 is mounted on each side plate 186 of the fountain, and is formed with teeth engaging the respective sector 185. Each plate 184 is mounted for sliding movement towards and away from the doctor on a curved bracket 191 conforming to the curvature of the printing cylinder 196. A flexible strip is riveted to the underside of each plate 184. The plates 184 are adjusted into abutting engagement with the doctor 159 by turning hand-wheels 190 secured to the stub shafts 188, and at the opposite ends the flexible strips of the plates 184 engage beneath the end portions of the sealing-strip 74. Specifications 435,877, 440,748, 440,774, 440,775, 495,842, and 495,844 also are referred to.