Abstract: The invention relates to an opening cylinder unit for open-end spinning machines. An opening cylinder (3) is mounted to transmit rotations on a shaft rotatable mounted in a bearing housing, which is covered at one front side by an axially fitted cover. The opening cylinder engages over the bearing housing forming a hollow space. In order that the hollow space can be freed from penetrated microdust in simple fashion, at least two cleaning ducts (15) disposed substantially in parallel to the axis of the opening cylinder are formed in the opening cylinder (3), which extend from the hollow space at least to one front side of the opening cylinder. The hollow space can be cleaned by these cleaning ducts using compressed air.

Abstract: A sliver opening apparatus for separating sliver into individual fibers for feeding of the individual fibers to the rotor of an open end spinning machine includes a rotating opening roller having a hollow interior and perforations from its exterior to its interior and air flow control elements disposed in the hollow interior of the opening roller. The air flow control elements define an opening located generally adjacent the sliver intake opening and an interior hollow chamber extending from the opening, the chamber being relatively large and the opening being relatively small. When the opening roller rotates, the air flow control elements cause the fibers from the incoming sliver to project toward the opening roller for optimum separation and combing by the teeth of the opening roller.

Abstract: A fibre opening device for use in apparatus for spinning fibres into yarns comprising a housing in which an opening roller is rotatably mounted, the housing having a trash separation zone and a fibre stripping zone and the roller having a cylindrical working surface from which combing elements project and being substantially hollow with holes extending through the wall defining the cylindrical working surface to permit a flow of air therethrough, wherein cleaning means are provided for the interior of the roller, the cleaning means consisting of a vacuum suction device and a compressed air jet device which remove trash, dust and short fibres from the interior of the roller. It is preferred that the air jet device is in front of the suction device relative to the rotation of the roller and on the side of the roller remote from where combing of fibres occurs.

Abstract: A fiber opening device of the spinning unit of an openend rotor spinning machine, for avoiding misalignments in the connection between the front end of the sucking tube of a travelling automatic service unit and the inlet port of the spinning unit, in order to prevent false air from being sucked in at this contact point. According to the invention, a sucking tube is provided with a self-adjustable sealing head having a front sealing surface to be fitted onto the front wall of the spinning unit. In the inner space of the sealing head a partially spherical concave surface fitted onto a mating, partially spherical convex surface provided at the end of the said sucking tube.

Abstract: A cleaning system for use with a fibre opening device used in connection with the spinning of fibres into yarns wherein an opening roller is mounted for rotation in a housing incorporating a trash separation zone and a fibre stripping zone and the roller has a cylindrical working surface with combing elements projecting thereform, wherein the roller is substantially hollow and has holes in the cylindrical wall defining its working surface to permit flow of air through the wall and the interior of the roller is divided into two or more compartments, and means are provided to remove air and entrained dust and trash from a compartment adjacent to the trash separation zone, and further means are provided to insert air or other gas into a compartment adjacent the fibre stripping zone.

Abstract: In an arrangement for open-end rotor spinning having a spinning rotor which, by means of a rotor shaft, is disposed in wedge-shaped gaps formed by pairs of supporting disks and is driven by means of a tangential belt, it is provided that a cleaning element is assigned to the peripheral area of the pressure roller.

Abstract: A textile machine, such as a spinning machine, is suction cleaned from spinning position to spinning position by a movable programmable robot provided with a suction device. This enables individual elements of the spinning machine prone to impurity or contaminant fouling to be maintained effectively free of such impurity depositions including fiber accumulations and the like without requiring use of the heretofore employed blowing-suction fucntion. The movable programmable robot is controlled by virtue of its being programmaged such that a suction trunk or nozzle thereof is guided in such close proximity to the individual elements to be suction cleaned that the suction cleaning operation can be effectively carried out and in a short period of time, following which the movable programmable robot is moved to the next spinning position for performance of the same or desired suction cleaning operation.

Abstract: Slubs are removed from an open-end spinning chamber by the application of suction to a debris-extraction duct by a valve opened to a suction line as the chamber is opened to a suction line as the chamber is opened for cleaning.

Abstract: The invention solves the problem of ejecting impurities out of a cleaning aperture in the fiber separating device of an open-end rotor spinning unit, particularly when there are various contaminations of fibrous slivers and of different kinds of textile fibers being processed. For this purpose an air flow regulator is provided in the separating device in an air supply duct communicating with the cleaning aperture. According to the invention, the air flow regulator is provided with an air directing wall near the outlet of the air supply duct and thus directs air flow into the cleaning aperture toward the fiber opening cylinder.

Abstract: An open-end spinning machine is provided which includes a cleaning element movable between two rows of adjacently aligned spinning units. The cleaning device sucks away and removes impurities from a stationary collecting device associated with impurity separation openings in opening devices of the spinning units. The cleaning device includes at least one suction element that extends into the stationary collecting element for drawing the impurities into the cleaning device.

Abstract: A method for piecing a thread formed in an open-end rotary spinning machine to an end of a previously formed thread, wherein spinning fibers are fed to at least one rotating fiber collection surface, the collected spinning fibers are further transported to a thread forming station connected to the fiber collection surface, and the end of the previously formed thread is joined to the spinning fibers transported to the thread forming station as the thread end is rotated, the pieced thread being continuously withdrawn from the thread forming station while spinning fibers are being continuously fed to the fiber collection surface includes a method for piecing a thread formed in an open-end rotary spinning machine to an end of a previously formed thread, wherein spinning fibers are fed to at least one rotating fiber collection surface of a spinning rotor disposed in a closed spinning chamber under negative pressure, the collected spinning fibers are further transported to a thread forming station connected to the

Abstract: A silver feed and opening device for open-end spinning applications comprises a housing having a rotatable opening roller associated with a pivotable guide plate having a first sliver guide portion for directing incoming sliver to the opening roller, a second arcuate fiber guide portion extending along a portion of the opening roller circumference in its direction of rotation, and a third debris guide portion extending outwardly from the opening roller and defining with the housing a debris discharge opening. The guide plate is of a unitary one-piece construction without joints between individual portions to prevent undesirable fiber accumulation which tends to occur in conventional devices. Each of the fiber and debris guide portions of the guide plate are spaced sufficiently from the sidewalls of the housing to form side slots which are a multiple of the thickness of the fibers, thereby to prevent accumulation thereof between the guide plate and the housing.

Abstract: A process for operating an open-end friction spinning machine is provided in which the spinning units each have at least two friction areas that form a yarn-forming region. At least a part of the friction effect is determined separately for each friction surface. The friction effect is compared between such friction surfaces. A corresponding open-end friction spinning machine apparatus is also provided.

Abstract: A bearing and driving unit for a spinning rotor of an open-end spinning unit is provided. A braking element is provided for braking a rotor shaft, and a cleaning element is provided for cleaning the rotor shaft. Actuating elements are provided for activating and deactivating the braking element and the cleaning element. The cleaning element is applied to the rotor shaft with a contact force which is controlled independent of a contact force control of the braking element.

Abstract: For piecing to an open-end friction spinning device with two friction spinning elements normally driven in the same direction of rotation and forming a nip therebetween, of which friction spinning elements at least one is capable of being subjected to suction, fibers are continuously fed to the nip and are then immediately removed from same. While fiber feeding continues uninterruptedly, the removal of fibers from such nip is then discontinued, so that fibers remain in the nip and form a rotating accumulation of fibers. A yarn end is then introduced to such accumulation of fibers. Newly formed yarn is then drawn off from the nip while fibers being fed continuously to such nip are continuously formed into such yarn. For such removal of fibers, a controllable suction air nozzle may be directed towards the above-mentioned nip from a side of the friction spinning elements opposite such nip.

Abstract: Open end friction spinning apparatus is provided in which there are one or more spinning units with respectively two adjacently arranged rollers, rotating in the same direction, and disposed to form a wedge-shaped slot therebetween for accepting fibers and spinning them into a thread of yarn by means of a friction effect. Devices are provided for monitoring the friction effect and adjusting the friction effect when necessary in order to maintain uniform spinning conditions at the individual spinning units and thereby control the quality of yarn produced.

Abstract: An open-end rotor spinning apparatus is provided which includes at least one spinning unit having yarn deflecting elements downstream from a yarn withdrawal duct. The yarn deflecting elements deflect yarn from the yarn withdrawal duct in a yarn spinning path. The yarn deflecting elements include at least one false-twisting edge. Yarn returning elements are provided for returning a yarn end to the yarn withdrawal duct past the yarn deflecting elements in a piecing path having a deflection less than the yarn spinning path deflection.

Abstract: An open end friction spinning apparatus is provided in which there are one or more spinning units with respectively two adjacently arranged rollers, rotating in the same direction, and disposed to form a wedge-shaped slot therebetween for accepting fibers and spinning them into a thread of yarn by a friction effect. Mechanical cleaning devices are provided for cleaning the surfaces of the rollers.

Abstract: A device for removing residual fibers from perforated friction surfaces of an OE-friction spinning machine includes a suction device including a controllable cut-off element connected to a suction source, a suction tube section connected between the cut-off element and the friction surfaces, and a controllable compressed air connection disposed in the suction tube section.

Abstract: A friction spinning unit includes a pair of cylindrical friction spinning rollers of which one has an air nozzle mounted adjacent to its periphery and able to discharge a current of air along the surface of that roller so as to move any unwanted fibres which may be on the surface of said roller. The air jet from the nozzle may provide a pneumatic barrier to hold fibres away from an annular passage between a surrounding shroud and the outer foraminous sleeve of the foraminous roller, and/or the air jet may be used to clear a fibrous slub from the spinning nip in the event of such a slub forming after a yarn break.

Abstract: An open-end friction spinning machine having a plurality of adjacently arranged spinning units is provided with one or more devices for conditioning the outer cylindrical surfaces of at least one roller of a roller pair contained in each spinning unit. Additionally, the spinning units are provided with one or more devices to monitor the friction characteristics of at least one of these rollers exhibiting a closed cover surface. The conditioning device is constructed so as to be responsive to a friction characteristic monitored by the friction characteristic monitoring device.

Abstract: Fiber material is conveyed over a sieve-like surface to remove dust from material. The fiber material is thereby exposed to a suction airstream which is guided through the sieve-like surface and which is guided away from the fiber material at an acute angle which is formed opposite to the fiber transport direction. The fiber material may be aligned in parallel before it is exposed to the suction airstream. In order to orient the suction airstream at the desired acute angle relative to the fiber transport direction, the fiber material is guided over sieve orifices which are inclined at the acute angle opposite to the fiber transport direction.

Abstract: Spinning device for producing a twisted thread of spinning fibers, the device having two friction elements rotatable in the same rotary direction and with mutually parallel rotational axes, and a position varying device for permitting the friction elements to be brought temporarily into another position relative to one another for cleaning purposes and including constructive members in the position varying device for assuring constant parallelism of the rotational axes.

Abstract: An arrangement for open-end friction spinning with two rollers forming a wedge-shaped gap is provided for separating the two rollers from a drive during a yarn breakage. A device reduces the speed of the roller rotating into the wedge-shaped gap earlier or faster than the roller rotating out of the wedge-shaped gap. Furthermore, a device is provided for switching off the suction device holding the producing yarn within the wedge-shaped gap during a yarn break.

Abstract: In a friction spinning process, a method is provided for preventing build up of dust and fly etc. inside a friction spinning machine (1) which method comprises the steps of introducing into the machine a flow of filtered air at a pressure just sufficient to substantially prevent the ingress of unfiltered air during spinning. The invention also provides apparatus for performing the method described, which apparatus comprises filter means (19), pressurizing means (20), ducting (22, 23) adapted to permit the outflow of clean pressurized air into the inside of the machine (1) adjacent the or each spinning head (3) at a pressure sufficient to substantially prevent the ingress of unfiltered air during spinning.

Abstract: In the case of a friction spinning machine having at least one spinning unit containing two friction rollers that are arranged next to one another to form a wedge-shaped yarn forming gap serving as the yarn forming zone, it is provided that in the area located opposite the yarn forming point the friction rollers are covered by a housing side and that by means of periodically switchable means, an air flow is produced between the housing side and the rollers.

Abstract: An open-end friction spinning machine is disclosed which has a plurality of adjacently arranged spinning units, each spinning unit including two adjacently arranged friction rollers driven in the same rotational direction and forming a wedge-shaped yarn forming gap therebetween. At least the friction roller rotating out of the wedge-shaped gap exhibits a closed cover surface. To assure consistent predetermined yarn characteristics, friction roller conditioning devices are disclosed for conditioning the friction surfaces of the friction rollers with closed cover surfaces.

Abstract: A method and apparatus for the cleaning of a spinning unit of an open-end friction spinning machine is disclosed for spinning units of the type containing two rollers arranged next to one another, drivable in the same rotational direction and forming a wedge-shaped yarn forming gap. It is provided according to the invention that a device for carrying out the cleaning is applied to the area of the wedge-shaped gap and that, during the cleaning, the yarn and fiber holding forces directed to the wedge-shaped gap during the spinning operation are eliminated or at least reduced. Preferred disclosed embodiments reduce the yarn and fiber holding forces during cleaning by reducing or interrupting the suction forces and by stopping or reversing the rotation of at least one of the friction rollers.

Abstract: A device for open-end friction spinning having two adjacently arranged rollers forming a yarn forming wedge-shaped gap therebetween is provided with a suction channel having an effect extending essentially in the direction of the wedge-shaped gap. This suction channel serves for drawing in a yarn end for a piecing operation. It is furthermore provided that this suction channel is selectively connectible to an air pressure source in order to provide a blast of air against the rollers in the region of the wedge-shaped gap. The blast of air serves to clean the rollers and remove debris prior to a piecing operation.

Abstract: An open-end friction spinning machine is disclosed which has a large number of spinning units arranged next to one another, each containing two friction rollers arranged next to one another to form a wedge-shaped yarn forming gap. By means of a joint drive the friction rollers are driven in the same rotational direction. A servicing apparatus is provided which in each case can be applied to a spinning unit, said servicing apparatus having an auxiliary drive for the friction rollers, said auxiliary drive containing an auxiliary drive element that can be applied simultaneously to the shell surfaces of both rollers.

Abstract: For the piecing of a yarn of a spinning unit of an open-end friction spinning machine, it is provided that a yarn an brought into the wedge-shaped gap is pieced, while forming a yarn piecing, which, before a renewed winding-up of the yarn, is cut out and is replaced by a yarn connection connecting the new yarn with the yarn leading to the spool. The formation of the yarn piecing takes place at a production speed that is reduced as compared to the normal spinning operational speed, said production speed being brought to the operational value only after the making of the yarn connection. It is also provided that the yarn spun during the formation of the yarn connection is taken up by a yarn storage device, which is emptied more rapidly because of the fact that the wind-up speed as compared to the withdrawal speed has a larger speed difference than the operational wind-up speed has with respect to the operational withdrawal speed.

Abstract: A feeding and opening device for open-end spinning machines is disclosed with a feeding table cooperating with a feeding roller and containing a fiberbeard support that is opposite the opening roller. The feeding table with fiberbeard support is held so that it can be swivelled from its operating position into a cleaning position. The swivelling can be carried out manually or by means of an adjusting element of an automatic servicing device. By means of the swivelling-away of the feeding table, the support surface of the fiberbeard support is exposed so that it can be cleaned in order to remove sticky components, such as honey dew or similar components.

Abstract: A method for piecing on a thread in friction spinning machines, having at least one friction surface with a perforated wall defining a spinning wedge at the wall includes moving the friction surface, eliminating the movement of transport air through the perforated wall of the friction surface, supplying fibers to the spinning wedge, sucking away the fibers, subsequently moving a thread to be pieced on into the spinning wedge, resuming suction of transport air through the perforated wall of the friction surface, ending suction of the fibers, and continuously withdrawing the thread from the spinning wedge, and a device for carrying out the method.

Abstract: An open end yarn spinning apparatus is disclosed which comprises a plurality of side by side spinning positions, with each spinning position including a circular spinning rotor, and aerodynamic bearings rotatably mounting the rotor. A maintenance carriage is adapted to move along one side of the apparatus, and the carriage mounts a cleaning device which may be introduced into the open side of the rotor upon disengagement of its drive means. To prevent the aerodynamic thrust bearing from being damaged during the cleaning operation by reason of the low speed rotation of the rotor, biasing means is provided for applying an axial force to the rotor to axially separate the thrust bearing and thereby avoid undue wear.

Abstract: A method of starting the operation of a friction spinning unit having friction surfaces displaceable in opposite directions and forming a spinning wedge, the spinning unit further having a fiber infeeding device, a thread take-up device for drawing a thread longitudinally through the spinning wedge, and at least one suction device acting upon the spinning wedge, at least one of the friction surfaces being formed by a sieve drum, the suction device having a suction nozzle acting upon the spinning wedge by sucking air through the wall of the sieve drum, by means of an automatic thread joining device, includes:(a) laying a thread into the spinning wedge;(b) initiating the infeed of spinning fibers into the spinning wedge;(c) connecting the friction surfaces with a thread-joining drive arrangement, and moving the friction surfaces in opposite directions with increasing speed;(d) continuously withdrawing the thread from the spinning wedge, and conducting it to a waste collector;(e) interrupting the travelling thre

Abstract: An open end friction spinning machine is disclosed which includes plurality of adjacently arranged spinning units which each have a pair of friction rollers forming a yarn twisting wedge slot. To accommodate cleaning of the friction rollers a mobile servicing cart is provided which is movable longitudinally along the machine to respective servicing positions adjacent spinning units to be cleaned. The servicing cart includes cleaning elements engageable with the rollers to clean them and air suction and blowing devices to assist in the cleaning and removal of contaminants.

Abstract: Open-end friction spinning apparatus is disclosed which includes a plurality of commonly driven spinning units arranged adjacent one another and each including a friction roller pair defining a yarn forming wedge slot therebetween. To facilitate cleaning of the friction rollers, pneumatically operated cleaning nozzles are provided for each friction roller to be cleaned. Some arrangements have the cleaning nozzles fixedly disposed at each spinning unit, with actuating valves being controllable by a mobile servicing unit. In other arrangements the pneumatic cleaning nozzles are carried by a mobile servicing unit and are selectively moved to cleaning positions adjacent the friction rollers of respective spinning units to be cleaned.

Abstract: The housing (1) of a opening device for an open-end spinning apparatus is lined by a thin-walled insert (3) which exhibits a perforation for the discharge of material (dirt, fibers) from the interior space of the housing (1). For the protection of the edge (310) bounding this perforation downstream relative to the fiber flow, an edge protector (4) is provided which is slidable onto the edge (310) engaging over the latter. For sliding the edge protector (4) onto the edge (310) to be protected, or for stripping it therefrom, a combined insertion and ejection tool (5) is provided which is introducible into the insert (3) and movable with a contact surface (51) along the peripheral wall (33) of the insert (3). The combined insertion and ejection tool (5) has a receiving throat (6) for the temporary reception of the edge protector (4) with a step (60) overhanging the contact surface (51) and in turn exhibiting a stripping edge (67).

Abstract: An apparatus for removing trash in an open-end spinning frame is disclosed herein. According to the invention, an open-end spinning unit is provided with a trash transporting chamber which is communicated with an opening which is formed on part of the inner peripheral surface of a space in which a combing roller is rotatably disposed and through which part of the circumferential surface of the rotating combing roller is exposed. The trash transporting chamber is so constructed that its interior is placed substantially under an atmospheric pressure, and a side wall thereof facing opposedly toward the opening is spaced from the circumferential surface of the combing roller exposed through said opening at a distance falling within a range from a dimension which is substantially equal to the diameter of the combing roller to a dimension which is about two times said diameter.

Abstract: Fiber separating device of an open-end spinning unit wherein the wall facing the fiber separating cylinder is provided with an impurity separating duct and with one or more air supply apertures. The air supply apertures are oriented symmetrically with respect to a plane substantially passing through the axis of the impurity separating duct and perpendicular to the axis of the fiber separating cylinder, the axes of said apertures including the same angles with the opposite walls of the impurity separating duct. The fiber separating device of the invention solves the problem of withdrawing impurities from fibrous materials supplied to the fiber separating device of open-end spinning unit, while reducing losses of the fibrous material.

Abstract: An apparatus for locating a servicing device which travels along a parent textile machine, such as a spinning frame, having a plurality of stations and stops at any designated station of the parent machine to there perform a servicing operation, such as yarn piecing or cleaning by use of fluid, such as compressed air or vacuum, supplied from a fluid source provided separately from the servicing device. The apparatus comprises, on each station of the parent machine, a stationary connector communicating with the fluid source and a locating guide member having a locating guide groove therein, and, on the servicing device, an air cylinder, a locating rod actuated by the cylinder toward and away from the locating guide member and engageable with the guide groove and a communicating member movable together with the locating rod and engageable with the stationary connector.

Abstract: Apparatus for separating fibers in open-end spinning units having a fiber separating cylinder in a cavity of a housing in which on a cylindrical surface there is provided a cleaning aperture with an impurity separating duct which latter opens by its impurity rebounding wall into a cylindrical impurity collecting chamber communicating, on the one hand, with an air supply aperture and, on the other hand, with an impurity sucking-off duct. In accordance with the invention at least one of the walls of the impurity sucking-off duct tangentially merges into the cylindrical wall of the cylindrical impurity collecting chamber, and the height of said sucking-off duct in the region of joining said collecting chamber is the same as or larger than the height of the outlet from said impurity separating duct into said collecting chamber.

Abstract: A dust-removing mechanism in an open-end spinning frame has a dust-removing chamber into which a dust-removing opening opens, the dust-removing opening being defined by a rear wall disposed upstream in the direction of rotation of the combing roller and having an edge and a front wall disposed downstream in the direction, there being an angle .alpha. formed between first and second lines passing through the front and rear wall edges and the center of the combing roller, an angle .beta. formed between a third line passing through the center of the combing roller and the center of an opening in the rotor and a fourth line passing through the center of the combing roller perpendicularly to the third line, an angle .UPSILON. formed between a surface of the front wall and a fifth line extending parallel to the fourth line through the front wall edge, and an angle .delta.

Abstract: In an opening unit for open-end spinning machines, which comprises a housing and a roller lined with sawtooth wire and rotatably arranged in the housing for separating the fibers along their path from the inlet to the outlet of the opening unit, a dirt separation duct is provided in the housing and is maintained under a reduced pressure. In the wall of the housing adjacent at least one side of the dirt separation duct a parallelizing element is inserted which comprises a plurality of saw tooth wire sections arranged in a side-by-side relationship and serving to balance the adverse effect of the dirt separation duct on the parallel flow of fibers on their path through the opening unit.

Abstract: An open-end spinning machine having an open-end spinning unit with novel apparatus for withdrawing impurities released in the spinning unit. An impurity releasing duct outlet of the sliver separation housing of the open-end spinning unit extends from said housing and has substantially the same cross-sectional inner height dimensions as those of the cleaning aperture, while a connecting tube inlet joined to said outlet is substantially conically flared, a gap being provided between said outlet and said inlet for the sucking-in of additional air.

Abstract: An open-end spinning machine having a plurality of spinning units (5) arranged side by side in a row extending in the longitudinal direction of the spinning machine. Each of the spinning units (5) has a filter (11) disposed at the front surface thereof and extending for substantially the entire width thereof. All the filters (11) arranged on the spinning units (5) disposed at one side of the spinning machine lie on a substantially identical imaginary plane slightly upwardly inclined from a horizontal plane when seen from the front to the rear. Each spinning unit includes a duct means (13) having air passages (15, 23, 27, 31) extending from the openings (13a, 13b, 13c, 13d) located adjacent to the filter (11) to the upper surface of a feeding roller (25), the upper and lower surfaces of a combing roller (21), and the periphery of the combing roller (21).

Abstract: Improved yarn spinning-in process and apparatus in open-end rotor spinning units which raises the quality of the spun-in point in the yarn to a level comparable with the quality of the entire yarn length. The yarn open end is pieced on to high-quality fibers while low-grade fibers are separated from the high-quality fibers and do not participate in the spinning-in process.

Abstract: The yarn formation area of a friction spinning apparatus, in which the rotating friction rollers and the feed duct lie closely adjacent, is quickly and simply cleaned of remaining fibres at a yarn break and protection is provided against damage caused by excess fibres entering the area. One of the rollers, which is imperforate, is mounted for pivotal movement away from the area and at a break suction through the other roller is temporarily closed off from one end of the area toward the opposite end to eject the remaining fibres. Return movement of the roller is guided to ensure proper return to the operating position.

Abstract: An open-end spinning unit has a housing having a cylindrical space, with a complementary cylindrical fiber-opening roller disposed in that space which communicates with a dust removing chamber having a dust separating zone and a dust discharge promoting zone, said zones being connected together through an intermediate passage positioned on the downstream side of a dust removing opening communicating with said space, a wall portion of the casing defining a downstream side of the dust separating zone being comprized by an inclined wall which faces an end portion of a partition separating said zones, the partition having an end wall which is inclined with respect to the vertical direction at an angle equal to or smaller than an angle of inclination of the inclined wall.

Abstract: An open end friction spinning machine is disclosed which includes plurality of adjacently arranged spinning units which each have a pair of friction rollers forming a yarn twisting wedge slot. To accommodate cleaning of the friction rollers a mobile servicing cart is provided which is movable longitudinally along the machine to respective servicing positions adjacent spinning units to be cleaned. The servicing cart includes cleaning elements engageable with the rollers to clean them and air suction and blowing devices to assist in the cleaning and removal of contaminants.