in the arrangement shown in fig1 two identical sorting apparatuses s1 and s2 , according to the invention , are placed on a printer d , wherein the sorting apparatus s2 sits on the sorting apparatus s1 . each of the sorting apparatuses comprises eight sorter pockets designated by a in fig2 . the printer d feeds printed sheets vertically in an upward direction through an outlet gap and consequently in the direction of the sorting apparatuses s1 and s2 arranged above the printer . as shown in fig2 the sorting apparatus s1 , which is placed directly on the printer d , comprises a housing 1 whose base 2 includes an opening or slot 3 forming a take - up site for sheets . guiding elements 4 , which project into the housing 1 from base 2 , adjoin the feed opening 3 and form a vertical sheet feed path 5 . the vertical central plane of the sheet feed path 5 contains a swiveling axis 6 which is arranged above the path 5 and is shown as a point in fig2 . axis 6 extends parallel to the base 2 and passes through a feed channel gap or nip , designated generally by 7 , which is swivelable around the axis 6 . as can also be seen in fig3 the feed channel comprises a pair of circulating members in the form of rollers 9 and 10 , which are arranged at a feed side or inlet end 8 of the channel . another pair of circulating members , which are formed by means of rollers 12 and 13 , are arranged on an outlet side 11 of the channel 7 . a pair of guiding elements 14 extend between the roller pairs 9 , 10 and 12 , 13 to guide sheets along channel 7 . the rollers have axle ends or journals 9a , 10a , 12a , engage with two shield plates 15 and 16 , which are located opposite one another , and form a unit with the rollers . the shield plates 5 and 16 are rigidly connected with one another by means of spacing elements , e . g . rods , not shown , and comprise an outwardly projecting axle end 17 in each instance . bearing eyes 0 , which receive the axle end 17 in such a way as to define the position of the swiveling axis 6 , are provided in two outer wall parts 18 and 19 which lie opposite one another . consequently , the unit comprising the feed channel 7 is swivelable around the axis 6 . as a part of the feed channel , the rollers 9 , 10 form a feed gap . while the rollers 9 , 10 and 12 are supported by means of their axle ends 9a , 10a and 12a directly in the shield plates 5 and 16 so as to be rotatable , the roller 13 is movable so as to swivel around the roller 12 and engages with a steering arrangement . in the embodiment shown , the axle ends 13a of the roller 13 penetrate a circular arc - shaped guide slot 21 in the two shield plates 15 and 16 in the sense of this steering arrangement and extend on both sides in a sliding block 22 , in each instance , in which they are supported so as to be rotatable . while the circular arc of the guide slots 21 have their center in the axis of the roller 12 , the sliding blocks 22 are displaceable in grooves 23 forming a connecting link . the grooves 23 , which are constructed identically in the side wall parts 18 and 19 , extend in a curved manner and enclose the guiding axis 6 by approximately 180 °. with reference to a circular arc - shaped path 24 ( fig2 ), which is traveled by the roller 12 during the swiveling of the feed channel 7 or of the shield plates 15 , 16 around the axis 6 , the grooves 23 comprise portions with a smaller and a larger radius of curvature . this will be discussed in more detail in the following . the shield plate 15 comprises the swiveling axis 6 adjacent a circular arc - shaped rack portion 15a which carries teeth 15b . a stepping motor 25 , which is fastened at the side wall part 18 , carries a pinion 27 on its shaft 26 , which pinion 27 meshes with the teeth 15b . an electric motor 28 , which drives the roller 12 via a pinion 29 and a toothed wheel 30 , which is connected with one of the axle ends 12a so as to be rigid against rotation , is fastened at the shield plate 15 . a pulley 31 , which is placed on the other of the two axle ends 12a so as to be rigid against rotation , is connected to a pulley 33 via a drive belt 32 . the pulley 33 is arranged on one of the axle ends 9a so as to be rigid against rotation . consequently , the electric motor 28 is in a drive connection with the roller 12 as well as with the roller 9 and drives both with the same circumferential speed . at 33 a control is indicated in a schematic manner . input 34 of control 33 is connected to the printer d or directly to a computer ( not shown ). the control 33 is connected to the stepping motor 25 and to the electric motor 28 via lines 35 and 36 . the control 33 is connected to a transmitter 48 and receiver 49 of a photocell via lines 46 and 47 , the photocell being arranged in the vicinity of the base 2 in the sheet feed path 5 . if , as shown , another sorting apparatus s2 is placed on the sorting apparatus s1 the control 33 is also in electrical connection with this sorting apparatus and governs it also ( not shown ). as can be seen in fig2 the sorter pockets a are formed by means of plates 37 which are fastened in the housing 1 in a manner which is not shown , and extend through an opening 38 . each plate 37 comprises a projection 37b at its inner end 37a , which projection 37b is semicircular in cross - section , wherein the projections of adjacent plates 37 leave open an intermediate space 39 between them . the ends 37a of the plates 37 are adjacent the grooves 23 . each of the plates 37 forms an output site with its projection 37b . another output site is formed by means of a slot 40 in the upper wall 41 of the housing 1 . adjacent the take - up site formed by the feed opening 3 , the sorting apparatus s1 comprises another take - up site which is formed by means of a feed gap 42 in a side wall 43 of the housing 1 , which feed gap 42 is arranged at the height of the swiveling axis 6 . in the shown arrangement of the sorting apparatus above the office machine , i . e . the printer d , the feed gap 42 remains unused . in the operation of the sorting apparatus s1 , the feed of the sheets printed by means of the printer d is effected by means of the feed opening 3 , wherein the sheet guide path 5 ensures its alignment with the axis 6 . when a sheet to be sorted arrives in the sheet guide path 5 , the feed channel 7 is in the position shown in fig2 . the photocell 48 , 49 reports the arrival of a sheet in the sheet guide path 5 as a corresponding signal to the control 33 which sets the electric motor 28 in operation for the drive of the rollers 9 , 10 and 12 , 13 . after a predetermined time interval required by the sheet in order to cover the path between the photocell 48 , 49 and the feed opening , the control operates the sorting process . the sheet which is still fed by means of the printer d can consequently run into the feed channel 7 or between the feed opening and the rollers 9 , 10 . while the rollers 9 , 10 feed the sheet from the printer through the feed channel 7 at the same speed , the channel is swiveled by means of the stepping motor 25 . the swiveling is effected corresponding to a sorting signal of the printer which is processed by the control 33 , in that this supplies a quantity of pulses to the stepping motor corresponding to a predetermined output site . assuming the control 33 has assigned the output site corresponding to the sorter pocket a5 to the sorting signal obtained by the printer for the output sheet , the feed channel 7 is swiveled into the swiveling position which is indicated by means of the dash - dot arrow line 44 . the assigned position of the rollers 12 , 13 is drawn in a dashed line . as explained , the circumferential position of the roller 13 relative to the roller 12 is determined by means of the configuration or the respective position of the groove 23 relative to the path 24 with reference to a determined swiveling position of the feed channel 7 . in the case of the swiveling position indicated by means of the arrow line 44 , the curvature radius of the groove 23 is approximately equal to the radius of the path 24 , and the axis 13b of the roller 13 practically extends through the path 24 . the rollers 12 and 13 can accordingly transfer the sheet without deflection into the sorter pocket a5 in the direction of the arrow line 44 . the angular velocity at which the stepping motor 25 swivels the feed channel 7 around the axis 6 , is selected in such a way that it has also traveled the largest required swiveling angle , i . e . the angle for reaching the sorter pocket a1 , when the start of the sheet has reached the end of the feed channel . as explained , it is assumed that the feed velocity in the feed channel is normally equal to that of the office machine , i . e . that of the printer in the present case . when the end of the sheet passes the photocell 48 , 49 , the latter produces another signal . the control 33 switches the electric motor 28 to a higher speed on the basis of this signal , by means of which the sheet is conveyed out of the feed channel at a higher feed velocity and is fed into the selected sorter pocket a5 . the sheet arrives completely in the sorter pocket a5 with its residual movement energy and is deposited with its rear end behind the projection 37b . in a predetermined time interval since the last signal of the photocell 48 , 49 -- sufficient to allow the sheet to exit completely from the feed channel 7 -- the control 33 causes the electric motor 28 to be stopped on the one hand and the stepping motor 25 to be controlled on the other hand in order to move the feed channel back in the direction of the initial position shown in fig2 . the described process is repeated as soon as the photocell 48 , 49 reports the arrival of another sheet . if a sheet is brought into the sorter pocket a1 , for example , the feed channel is swiveled into the direction indicated by means of the arrow line 45a . in so doing , the roller 13 also swivels relative to the roller 12 in such a way that the sheet undergoes a deflection corresponding to the arrow direction 45b when exiting from the feed channel 7 . the direction of the deflection is selected in such a way that the sheet encloses the smallest possible angle a relative to the sorter pocket , i . e . its plate 37 , and nevertheless reaches an intermediate space 39 . an opposite swiveling of the roller 13 relative to the roller 12 is effected in an analogous way in order to deposit a sheet in the sorter pocket a8 . a deflection of the sheet is also possible in a direction which is practically parallel to the sorter pocket . the portion of the groove designated 23a is not needed in the shown embodiment , but this allows sheets to be delivered vertically downwardly in another arrangement of the sorting apparatus s1 . to the extent that it is desired , another photocell can be assigned to the feed channel 7 itself and arranged in the vicinity of its outlet side or at the outlet from the rollers 12 , 13 . the other photocell can accordingly replace a portion of the timing circuit and can supply a signal to the control 33 when the end of the sheet passes in order to stop the electric motor 28 and particularly to swivel the feed channel back into the initial position . it is possible to control the beginning of the swiveling movements of the feed channel over time instead of by means of sensing devices or photocells . in the embodiment shown , it is assumed that the electric motor 28 is immediately started up as soon as the photocell 48 , 49 signals the arrival of a new sheet in the feed path 5 so that the rollers 9 , 10 , 12 , 13 are driven in the forward rotational direction . the rollers , in any event , are already rotating when the sheet arrives at the inlet end 8 of the feed channel . however , it should be appreciated that for the purpose of aligning or properly positioning the sheet , or to avoid a slanted introduction into the feed channel 7 , it is also possible to drive the roller first with a time delay , to wit , in such a manner that the sheet with its leading edge in the gap strikes the rollers 9 , 10 which are then still at rest . the leading edge of the sheet then aligns itself in known manner parallel to the rollers 9 , 10 while there occurs in the sheet a certain bulging . after the delay time is over , the electric motor 28 starts up the rollers in the forward rotational direction so that the rollers 8 , 9 draw the sheet in an aligned position , into the feed channel 7 . in order to obtain the same result , it is also possible to utilize the corresponding signal of the photocell 48 , 49 by the control 33 for the driving of the electric motor 28 in a reverse rotational direction . in such a case , when the sheet with its leading edge reaches the rollers 9 , 10 , the latter are then already in motion in a reverse rotational direction . since the sheet cannot enter the feed channel 7 , it bulges and the leading edge of the sheet aligns itself parallel to the rollers 9 , 10 . after a corresponding time delay , the control 33 switches the electric motor 28 to reverse again and the sheet is drawn in , in aligned position , by the rollers which now rotate in the forward rotational direction . as explained above , the sheet can be removed or ejected from the feed channel with a higher speed than the speed at which the sheet is drawn into the feed channel . by this means it is possible to shorten the time necessary for the sorting procedure . this is of importance particularly if output sites are present which make it necessary to tilt the feed channel about larger angles . it should also be pointed out that wear on the members or elements which are driven by the electric motor 28 can be significantly reduced in that the motor is only switched on during the feeding of a sheet . this also of course reduces the current consumption of the apparatus . instead of operating the apparatus so that the sorter or sorters obtain a sorting signal from the sheet delivering printer for each sheet , it is also feasible to design the control 33 in such a manner wherein a corresponding number of output sites are started up one after the other in a predetermined sequence , for example corresponding to a number of copies or sheets generated by the printer . while a specific embodiment of the invention has been shown and described in detail to illustrate the application of the inventive principles , it will be understood that the invention may be embodied otherwise without departing from such principles .