Patent GB-854053-A (GB)
Title: Improvements in or relating to segregating apparatus for thin flat articles such as letter mail
Inventor: COPPING GEOFFREY PERCY
IPC: B07C1/14
Filed: 1957-04-11
Abstract: 854,053. Sorting solid materials. POSTMASTER-GENERAL. April 11, 1958 [April 11, 1957], No. 11932/57. Class 117 [Also in Groups XVI and XXX] Apparatus for segregating from a stream of differently sized thin flat articles those articles having a dimension in the direction of movement of the stream which is less than a predetermined length comprises at least two pairs of gripping rollers spaced apart vertically to provide a gap equal to the predetermined length between the or each two adjacent pairs, the rollers being driven so that articles fed to the first pair of rollers are conveyed upwardly towards the second pair of rollers, those which are longer than the gap between the rollers being gripped and further conveyed upwardly by the second pair of rollers, while the shorter articles fall back to be engaged between one of the rollers of the first pair and a discharge roller and are discharged downwardly. In one embodiment for sorting letters, Fig. 1, only two pairs of gripping rollers 2, 3, and 5, 6 respectively are used. The rollers 2, 5 are mounted on fixed axes and are driven, whilst the rollers 3, 6 are journalled in the ends of depending arms 7, 8 respectively, so as to bear against the corresponding rollers 2, 5 by gravity. Discharge rollers 11, 13 are journalled in the ends of further depending arms 12, 14 respectively so that they bear against the rollers 2, 3. Each of the arms 12, 14 carries a series of closely spaced guide plates 20 the inner edges of which define guides to direct the long letters 17 into the pinch of the rollers 5, 6 whilst at the same time guiding the short letters 18 into the pinches of the rollers 2, 11 and 3, 13 for discharge downwardly. In the form shown in Fig. 10a, the letters are led into the pinch of the lower rollers of the assembly by an endless belt 32 and pairs of gripping rollers 34, 35 and 43, 44, and the discharged short letters 55 are received in two stacking devices each comprising a rotating star wheel 54 and a stack-forming plate 55 which is urged towards the star wheel by a spring 55d from which a cord 55b extends over a pulley 55c to a sliding block on which the plate 55 is mounted. The long letters are received in a shoot 23 from which they pass between one of the upper rollers of the segregator and a roller 49 carried by a further depending arm to a further stacking device similar to the other two stacking devices. Since long letters may be fed to the segregator other than in the end-on position, the feed to the segregator preferably includes a shaking device to dispose the letters either longitudinally or transverse to their direction of feed, and there is provided a second segregator disposed at right angles to the first segregator to receive the letters discharged from the first segregator, the arrangement being such that long letters discharged with the short letters in the first segregator are presented end-on to the second segregator. In another embodiment, Figs. 6a, 7, 8, in order to avoid short letters being carried upwards and discharged with the long letters, each segregator comprises eight segregating gaps between pairs of vertically spaced rollers, the segregator being built up of units 79. Each unit except the two lower units 79b, 79c is constructed as shown in Figs. 7, 8, and comprises a driven shaft 86 journalled in brackets 85a, 85b adapted to be bolted to the frame 58 of the segregator. This shaft carries a series of 89 and is driven through helical gearing 91, 92 from a vertical shaft 93 having at its lower end a coupling 95. When the units are assembled in the frame 58 all the shafts 93 of the units are in line and are coupled together and to a shaft 96, Fig. 6b (not shown), which is driven through helical gearing 101, 102 and a sprocket connection 98 by a motor 61. The shaft 86 of each unit has freely suspended from it a pair of arms 103 between the lower ends of which is journalled a shaft 105 carrying rollers 106. These rollers bear against the driven rollers 89a of the unit below to discharge the short letters at the lefthand side of the unit. Guide plates 107 are secured in spaced relation between the arms 103 by bolts 108 and sleeves 109. A second pair of arms 110, 111 is freely suspended from the bracket 85a, 85b and a shaft 112 carrying rollers 113 is journalled between their lower ends. The shaft 112 is driven from the shaft 86 through spur gears 118, 121 and chain gearing 120. The rollers 113 bear against the driven rollers 89a of the unit below to provide the letter feed into the unit. The rollers 89 cooperate with the rollers 113b of the next unit above to provide the discharge for long letters upwardly into the next unit. A third pair of arms 122 depend freely from the shaft 112. A shaft 125 carrying rollers 126 is journalled in the lower ends of the arms 122. These rollers will bear against the rollers 113 of the unit below (not shown) to provide the short letter discharge at the right-hand side of the unit below. Similarly the right-hand short letter discharge of the unit described is effected by the rollers 126b of the unit above bearing against the rollers 113 of the described unit. Spaced guide plates 124 are recessed between the arms 122. All the units are similar except the lower units 79b and 79c, the former having the arms 122 and rollers 126 omitted while the latter merely consists of a driven shaft 86 carrying the rollers 89. Rollers 130 bear against the rollers 89 of the top unit to complete the long letter discharge. A shoot 80 receives the long letters for delivery to a conveyer belt 84. The units preferably have the same vertical spacing between input and output pairs of driven rollers but they may have different vertical spacings of the rollers to sort out the letters into groups exceeding more than one predetermined length.