fig1 shows an apparatus which is constructed and assembled to transport filter rod sections ( hereinafter filters ) 7 of unit or multiple unit length , e . g ., double unit or quadruple unit length . the apparatus comprises a sender 1 , a receiving station 3 ( e . g ., a station accommodating a machine known as filtromat which is distributed by the assignee of the present application ), and a pneumatic conveyor 2 which defines an elongated path extending from the sender 1 to the receiving station 3 and serving to guide successive filters 7 lengthwise in the direction indicated by the arrows 33 . filtromat is a machine which is designed to supply or convey filters to consuming or processing machines , e . g ., to filter tipping machines wherein tobacco smoke filters of selected lengths are united with plain cigarettes , cigars or cigarillos to form therewith filter cigarettes , cigars or cigarillos of desired length . the sender 1 comprises a horizontal rotary drum - shaped conveyor 4 ( hereinafter drum ) having axially parallel peripheral flutes 6 separated from each other by elongated ridges or ribs 9 and communicating with suction ports 8 in certain angular positions to attract and transport discrete filters 7 sideways from a source 12 toward positions of alignment with the inlet of the pneumatic conveyor 2 ( hereinafter conduit for short ). the drum 4 can receive torque from a horizontal shaft 11 which is rotatable relative to two spaced - apart sleeve - like bearing members 14 , 16 and is driven by a suitable prime mover ( e . g ., an electric motor ), not shown . successive ridges 9 of the drum 4 can cooperate with a mobile sealing member 13 to ensure predictable optimum axial propulsion of successive filters 7 arriving to positions for abrupt advancement into the inlet of the conduit 2 . the illustrated source 12 is an upright chute or duct which receives filters from one or more makers and admits successive filters sideways into oncoming flutes 6 at a location b . the location of axial transfer of filters 7 is from their flutes 6 into the inlet of the conduit 2 is shown at c . the conduit 2 of fig1 to 4 includes a first stationary section which is connected with the sender 1 in the region of the bearing member 14 , a second stationary section having a discharge end located at the receiving station 3 , and a mobile intermediate section 36 between the two stationary sections and rather closely adjacent the sender 1 . as indicated by the left - hand arrow 33 of fig1 the mounting and the operation of the conduit 2 are such that successive filters 7 arriving from the source 12 are propelled upwardly , at least in the section 36 . the aforementioned sealing member 13 is movable between the illustrated raised ( sealing ) position , which it assumes during propulsion of a filter 7 from its flute 6 into the conduit 2 , and a lowered or retracted position in which the parts 4 , 13 define an arcuate clearance 17 . the upper side of the sealing member 13 constitutes a concave surface having a radius of curvature complementary to that of the periphery of the drum 4 . the concave surface of the sealing member 13 can abut the adjacent convex surfaces of the bearing members 14 , 16 in such a way that the elongated surfaces ( top lands ) at the radially outermost portions of the ridges 9 occupying the location c do not actually contact the sealing member 13 . the drive shaft 11 for the drum 4 extends axially beyond at least one of the bearing members 14 , 16 and is journalled , without radial play , in stationary walls ( not shown ). the reference characters 18 denote tensioning crossheads which fixedly connect the bearing members 14 , 16 with a preferably plate - like support , not shown . such support further serves to guide a carrier 15 for the sealing member 13 as well as to mount two compressed - air pistons 19 which are utilized to move the sealing member 13 and its carrier 15 up and down between their operative and retracted positions . the illustrated mounting of the sealing member 13 for vertical movement renders it possible to highly reliably establish a clearance 17 of predetermined ( optimum ) width ; such clearance is established at an end face and serves to ensure evacuation of air ( at the location c ) between the drum 4 and the adjacent surface of the bearing member 14 . the sender 1 is further provided with means for supplying into the flutes 6 a pressurized gaseous fluid ( normally compressed air ) which serves to expel the filter 7 at the location c lengthwise into the inlet of the conduit 2 . to this end , the drum 4 comprises a flangelike control member 22 which is provided with elongated air passages 23 , one for each of the flutes 6 . furthermore , the carrier 15 is provided with a transverse bore 24 which is arranged to communicate with a transverse bore 27 of the sealing member 13 . the bore 27 is located between two sealing rings 26 installed between the sealing member 13 and the carrier 15 . the end portions of the pistons 19 are provided with or constitute heads 28 which extend through the carrier 15 . the end faces of the heads 28 bear midway upon the sealing member 13 , and these heads are located within the carrier 15 and are coupled thereto with a predetermined radial play . the bearing member 14 is adjacent the location c and has a sealing surface 31 ( this surface contacts the sealing member 13 ) as well as an axially parallel discharge opening 32 which registers with the inlet of the conduit 2 and serves to direct successive filters 7 into such inlet . in order to ensure that successive filters 7 will readily advance along and beyond the edges of the sealing surface 31 , there is provided a ramp 34 which slopes upwardly toward the sealing surface 31 ( as seen in the direction , indicated by the right - hand arrow 33 , of propulsion of filters 7 into the conduit 2 ); such ramp is machined into the adjacent supporting and sealing surface of the sealing member 13 . the section 36 of the conduit 2 is adjacent the latter &# 39 ; s inlet , and its details are shown in fig2 and 3 . this section extends from a lower level to an upper level along an arc of less than 180 ° ( the illustrated arc matches or approximates 90 °) and forms part of the mobile module 38 . the latter further includes an arcuate part 37 which is or which can be designed and mounted to prevent the section 36 of the conduit 2 from changing its curvature so that such section can be repeatedly connected to and disconnected from the adjacent ( straight or substantially straight ) additional sections of the conduit 2 by any suitable fastener means . the section 36 can be integrated into the adjacent . sections of the conduit 2 without departing from the spirit of the invention . the convex underside of the section 36 is provided with an arcuate guide 39 which is located beneath the arcuate part 37 and defines a concave surface for lengthwise advancement of successive filters 7 upwardly and toward the receiving station 3 . the guide 39 is flanked by arcuate openings ( such as slots ) serving to establish communication between the interior of the section 36 and an adjacent chamber 41 which gathers loose solid particles being expelled from the path for the filters 7 . such expulsion can take place in part under the action of pressurized gaseous fluid which is used to propel filters 7 toward the receiving station 3 , and in part under the action of centrifugal force . the lower portion of the convex underside of the section 36 is overlapped by a cover 43 which prevents pressurized fluid from flowing full blast into the chamber 41 . at least the major portion ( 42 ) of the cover 43 is or can be made of a suitable resilient metallic sheet material , and the upper end portion 44 of the cover constitutes a suitably bent deflector or lug which serves to establish an optimum flow of gaseous fluid between the adjacent portions of the chamber 41 and the portion of the path defined by the section 36 . the sheet metal part 42 of the cover 43 is preferably precurved ( preshaped ) in the manufacturing plant so that its underside ( which faces the chamber 41 ) exhibits a convex shape . the lower part of the section 36 is provided with an outlet 46 for intermittent or more or less continuous evacuation of intercepted and gathered solid particles from the chamber 41 . fig2 shows one embodiment of the outlet 46 ; the latter defines an upright compartment 47 with a first manually operable valve 48 at the upper end and a second manually operable valve 49 at the lower end . in the embodiment of fig5 the valves 48 , 49 are opened automatically ( when necessary or at preselected intervals ), e . g ., as a function of time . to this end , the outlet 46 of fig5 employs two fluid - operated cylinder - and - piston units 50 , 51 , one for each of the respective ( automated ) valves 48 , 49 . the exact construction of the parts constituting the sender 1 forms no part of the present invention . as a rule , the operation of this sender is fully automated because it is expected to furnish several thousand filters per minute . the mode of operation of the improved apparatus , and particularly of the parts shown in detail in fig2 - 4 and 5 , is as follows : in order to propel a filter 7 into the conduit 2 upstream of the section 36 , the mobile sealing member 13 is lifted from its lower end position to the illustrated raised or operative position ( for example , the sealing member can be moved to its lower end position , at fixed or arbitrary intervals , for the purpose of inspection and / or cleaning ) when the sealing member 13 reaches the raised position of fig1 the extent of movability of the heads 28 of the pistons 19 relative to the carrier 15 ( i . e ., the play of the aforediscussed loose connection between the carrier 15 and the heads 28 ) is such that the sealing ring ( s ) 26 is ( are ) stressed between the sealing member 13 and the carrier . consequently , the crossheads 18 are in the process of taking up the compressive and bending stresses being applied to the bearing members 14 and 16 . the corresponding system of the sender 1 shown in fig1 is then under requisite stress . however , and since the diameter of the drum 4 is relatively small , there is established the aforediscussed predetermined clearance between the periphery of the drum and the sealing member 13 ; this allows for the friction - and hence wear - free operation of the sender 1 . when the prime mover for the drive shaft 11 is on , successive flutes 6 of the continuously rotating drum 4 accept discrete filters 7 from the source 12 at the location b and deliver discrete filters at the location c . the drum 4 is or can be driven at a constant speed , also during those stages of operation of the sender 1 when the filters 7 are in the process of being actually propelled from their flutes 6 axially and into the inlet of the conduit 2 . actual propulsion takes place when a flute 6 registers with the bore 32 of the bearing member 14 ; a blast of pressurized pneumatic fluid is then free to flow from the transverse bore 24 of the carrier 15 , into the transverse bore 27 of the sealing member 13 , thence into the air passage 23 then disposed at the location c , and ultimately into the aligned or registering flute 6 . the thus admitted blast or jet of pressurized gaseous fluid expels the filter 7 from its flute 6 in the direction of the right - hand arrow 33 shown in fig1 and into the inlet of the conduit 2 . the ramp 34 is effective to further ensure entry of an axially advancing filter 7 from its flute 6 into the conduit 2 . solid particles ( such as charcoal granules ) which are normally confined in the tubular envelope of a filter 7 ( such granules can be distributed in the rod - like filler of the filter ) are likely to escape from their envelopes ( such envelopes can be made , for example , of cigarette paper ) due to repated changes of direction ( from sideways to lengthwise and / or vice versa ), stoppages , acceleration and / or deceleration of a filter on its way into and through the source 12 and thence toward and into the inlet of the conduit 2 . the thus obtained stray particles tend to clog the conduit 2 and / or to adhere to ( and to thus cause coloration and / or other types of contamination of ) the external surfaces of the filters 7 . therefore , there exists an urgent need for predictable , reliable , timely , simple and reproducible evacuation of loose solid particles from the path between the sender 1 and the receiving station 3 . such evacuation takes place in the region of the arcuate part 37 where the stray solid particles are acted upon by centrifugal force along an arc of 90 ° and are thus propelled into the chamber 41 . the cover 43 prevents solid particles from migrating out of the chamber 41 and back into the section 36 of the conduit 2 . the deflector 44 establishes a fluid flow which actually draws loose solid particles from the interior of the section 36 into the chamber 41 , namely a downwardly oriented fluid flow . solid particles which gather in the lower portion of the chamber 41 can be caused to descend into the compartment 47 in response to manual opening of the valve 48 shown in fig2 . once the valve 48 is closed again , the person in charge opens the valve 49 to permit the accumulated solid particles to descend from the compartment 47 into a collecting receptacle ( not shown ) or onto or into a suitable conveyor , or to be caused to advance to another destination , e . g ., back into the respective magazine of the machine which is utilized for the making of filters containing particles of charcoal and / or other material ( s ). the outlet 46 should be put to use as frequently as is necessary to ensure that the pressure of conveying fluid in the conduit 2 cannot drop below a minimum acceptable ( lower threshold ) value . the automatic arrangement 50 , 51 of fig5 which can be utilized in lieu of manually operated valves 48 , 49 shown in fig2 can be set up to open the valves 48 , 49 of fig5 sequentially at preselected intervals or in response to monitoring of the accumulations of solid particles in the compartment 47 . the mobile module 38 of fig2 can be replaced with a piece of arcuate pipe when the conduit extending from the sender 1 toward the receiving station 3 is set up to deliver a file of filters which are devoid of solid particles . such module thus contributes to versatility of the improved apparatus . an important advantage of the improved apparatus is that stray solid particles can be evacuated from an upstream section ( 36 ) of the conduit 2 , i . e ., in a region where the pressure of the pneumatic fluid is still very high . such evacuation is possible because loose solid particles advancing toward and into the arcuate section 36 are still being acted upon by a pronounced centrifugal force . another advantage of the improved apparatus is that evacuation of loose solid particles from the section 36 of the conduit 2 into the collecting chamber 41 does not entail a pronounced drop of pressure of the fluid flow which is utilized to propel successive filters lengthwise from the sender 1 ( or an equivalent sender ) into the receiving station 3 . a further advantage of the improved apparatus is that the evacuation of collected solid particles ( including dust ) from the chamber 41 ( via outlet 46 ) constitutes a simple and time - saving procedure which can be carried out while the conduit 2 continues to deliver filters to the station 3 . without further analysis , the foregoing will so fully reveal the gist of the present invention that others can , by applying current knowledge , readily adapt it for various applications without omitting features that , from the standpoint of prior art , fairly constitute essential characteristics of the generic and specific aspects of the above outlined contribution to the art of transporting filter rods and , therefore , such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the appended claims .
apparatus for transporting rod - shaped tobacco smoke filters which contain and / or carry particles of charcoal and / or other solid particulate tobacco smoke filtering and / or flavoring material . a sender directs a series of successive filters lengthwise into a pneumatic conduit wherein the filters advance toward a receiving station . a section of the conduit has an arcuate shape and advances successive filters from a lower level to a higher level . the underside of the section has an elongated arcuate opening which is overlapped by a cover in such a way that any solid particles which became separated from the filters can be expelled into a neighboring chamber due to fluid pressure in the section as well as under the action of gravity and / or centrifugal force . such particles are evacuated by way of an outlet at the lower end of the chamber , either by manually operated valves which control the admission of particles from the chamber into a compartment and from the compartment , or by automatically operated valves which open at close at predetermined intervals .