US 2978753 A
Description (OCR text may contain errors)
April 11, 1961 J. K. P. MACKIE TEXTILE DRAFTING APPARATUS 2 Sheets-Sheet 1 Filed April 8, 1958 M r 0 m m a m A k April 11, 1961 Filed April 8, 1958 J. K. P. MACKIE TEXTILE DRAFTING APPARATUS 2 Sheets-Sheet 2 Inventor UH flin /e. Mum's Attorney-4 from its datum position.
Unitfid tates Patent 2,978,753 TEXTILE DRAFTiNG APPARATUS John Kay Pringle Mackie, Belfast, Northern Ireland, assignor to James Mackie & Sons Limited, Belfast, Northern Ireland, a British company Filed Apr. s, 1958, Ser. No. 727,081
Claims priority, application Great Britain Apr. 15, 1957 i 8 Claims. (Cl. 19-70 I This invention relates to machines for drafting textile slivers inwhich mechanism is provided for the automatic variation of the draft on the machine corresponding to the weight or thickness of the sliver being fed.
In many cases the incoming sliver will vary considerably in weight or thickness from. point to point along its length and by increasing the'draft at the points of greater thickness and reducing it at the points of lesser thickness the resultant product can be given very much greater uniformity. If the thickness of the incoming sliver is measured this may be done by means of a pair of rollers between which the sliver passes, the rollers being mounted for relative displacement towards and away from one another, and the degree of the displacement being a measure of the thickness of the sliver. It is then necessary to I adust the draft of the machine in accordance with variations of thickness as measured by these rollers. It is, however, essential that the variation in the draft shall only be applied when the point in the sliver, whose thickness has already been measured, reaches the drafting zone. Since a short interval of time must elapse while the sliver passes between the measuring rollers and the draftingzone, it is necessary to apply a small time delay to the mechanism for controlling the draft.
The-basic principle of time delay mechanism which may be used for this purpose is set out in British specification No. 27,304 of 1911. As described in this specification the relative displacement of the measuring rollers controls a setting member which engagesa series of axially movable rods mounted around the periphery of a rotating drum, the axial position of each rod being adjusted by the setting member as the rod passes the latter.
of the rods each rod is formed with annular grooves which engage with a grooved surface on a locking member situated at the point where the rods engage the transmitter. This prevents endwise movement of the rods by the transmitter but entails the adjustment of each rod in increments equal to the pitch of the grooves. In order some and diflicult to accommodate in the machine.
At another point around the periphery of the drum is situated a second member or transmitter which is acted upon by each passing rod and is displaced by an amount dependent on the axial position of each rod. The transmitter in its turn actuates draft control mechanism, being connected to a variable speed driving mechanism whereby either the speed of the feed or of the delivery of the "machine may be varied. The time taken for each rod to pass from the setting member to the transmitter represents the time delay introduced which is arranged to be equal to the length of time taken for the sliver to move from the measuring rollers-to the drafting zone. In practice the'time delay imposed by the movement of the rods is slightly increased by the time of response of the draft control mechanism.
The outcome is that the draft of the machine is controlled in accordance with the axial position of successive rods which in turn is dependent on the varying weight or thickness of the sliver.
In the arrangement described in the above-mentioned specification the rods are free to be moved axiallyby the setting member and the transmitter is arranged to bear against the endsof the rods so that it is displaced A further disadvantage is that the locking mechanism only comes into action in the region of the point Where the rods engage the transmitter and there is a danger that they may be moved axially due, for example to vibration during their passage between the setting member and the transmitter. This disadvantage also applies to an alternative arrangement which has been proposed and in which the movement of the transmitter is at an angle to the axis of each rod, thereby reducing the end thrust imposed.
According to the present invention a time delay mechanism for the purpose referred to above includes a series of slidable members movable around a closed path between the setting member and the transmitter, each slidable member having its position controlled by the setting member and havinga surface sloping at asmall angle to the path of sliding motion; this surface acts directly or indirectly on the transmitter so that the setting member controls in turn the position of each slidable member and hence the position of the transmitter.
It will be understood that as a slidable member is adjusted by the setting member there isa corresponding effective transverse displacement of its sloping surface at anyone point and it' is this displacement which is used either directly or indirectly to adjust the transmitter.
ber so that the rod takes up an axial position depending In this connection the.
on that of the slidable member. term rod is not intended to be limited to a member of circular cross section but includes any member capable of sliding under the action of the corresponding slidable member and of subsequently acting on the transmitter. In view of the fact that each rod is pressed into contact with its corresponding slidable member by means of its bias and also that the'surface of the slidable member slopes at a small angle to its direction of motion, each slidable member and rod are locked together so that once they have been set there is very little or no danger of displacement either during travel between the setting member and the transmitter or while the rod is acting on the transmitter.
Relatively large movement of a slidable member will produce a much smaller movement ofv its associated rod and if, for example, the angle of slope of the surface of the slidable member is seven degrees, a movement of a slidable member of one inch will give a correspond ing movement of its rod of approximately one eighth of' transmitter and thus enables the pitch of therods to be the setting member 2 in the direction oftne seen in Figure 4.
made comparatively small, thus making the whole mechanism compact. Preferably the slidable members are arranged to slide substantially axially ina supporting drum (thus occupying approximately the position of the rods in the previous form of construction referred to) while the rods slide radially in t-hedrum. Alternatively,'however, the arrangement may be reversed, the slidable members sliding radially and the rods sliding axially-of the drum; In either case the rods are locked against movep angle of slopeis of the order of seven degrees.
ment along their own axes so that there is little or no danger of theirbeing displaced ,by the end thrust exerted on them by the transmitter and the latter may' be arranged to move along the axis of each successive rod without trouble. i
In order to overcome the effect of friction exerted ;by the'rods on the slidable members, while the latter are being acted on by the setting member a cam is preferably provided for forcing each rod back against its resilient bias so'as to relieve the pressure on the slidable member while this is being acted on by the setting member. This allows the slidable member to be ad justed freely but the cam is so shaped that assoon as the setting of the slidable member is complete the rod is released to bear against the sloping surface so that the two are then locked togetheras previously described.
Mechanism in accordance with the invention will now be described in more detail bywayof example with reference to the accompanying drawings in which:
Figure 1 shows the general arrangement including additional mechanism associated with the setting member and the transmitter; i
Figure 2 is a detailed view of measuring rollers shown in Figure 1; i H
Figure 3 is a cross sectional'view o'fa rotary drum appearing in Figure l; and I i V Figure 4 is a detailed view seen in the direction of the arrow IV in Figure 1. 7
The apparatus 'shownin Figure 1 comprises essentially time delay mechanism including emery drum ii, a a
setting member 2 and atrian smitter in the ram; of la roller 3. in addition, it includes a pair of measuring rollers 4 which control the setting member 2 and. also variable speed gearing indicated generally as 5, controlled by the transmitters. 7
Referring to these main components in more vdetail, the measuring rollers 4 which are also seen in Figure 2 comprise a lower roller 16 turning in a fixed mounting and an upper roller ll carried by a short armylZ of p a bell-crank lever pivoted at-13 and having a considerably longer downwardly extending arm 14. The roller =10 is formed with flanges 15 which embrace the. roller ll to constitute a c nfinedpassage for sliver-16 passing between the tworollers. v
The sl ver 16 is considerably condensed foritspassage between the measuring rollers; so that any minor. variaticns in its thickness have an enhanced effect in producing displ-acements of the r ovable upper rolleralll. Cons: uently any variations-in the thickness of thesliver 1'6 tend to rock the bellcrank lever about its pivot .13,
any increase in the-thicknesscausing rocking movement in a counter-clockwise direction astseen in Figure- 2 and vice versa. -The arm ldis'fitted .at its lower'end with a roller Jill bearing against awsurfacell on-a lever .arm pivotedat 22 to a fixed mounting 23.- At a its :upper .endthe lever 21 carries the setting member 2 which, as shown in Figure 4, comprises apair of side plates25 and '26 which,'-at their upperfend, are substantially parallel but which are flared outwardly at their lower ends. Consequently any displacement'o'f the measuring roller 11 by variations in the thickness of the sliver 16, produces a corresponding magnifide movement of arrows 27 r The setting member 2 contro ls the position of aQseries 5 flat edge 32 hearing against a corresponding surface in a slot in the drum so that it can slide axially of the drum. The opposite edge of each wedge is formed with a surface 33 sloping are small angle to the direction of sliding movement. As shown in the drawing the Co-operating with each wedge .is a rod sliding in a radially extending slot in the drum 31. Each rod is formed with a cut-away portion 35 in the region of its middle, the upper edge of which defines a shoulder 36 15 bearing against the sloping surface 33 of the'wedge 30.
This shoulder is biased into engagement with the wedge by means of a compression spring 37 acting between a surface 38 on the drum 31 and a washer 39 on the end of the .rod. As previously described the position of the 20 wedgesfitl is controlled by means .of the Setting member 2 and by virtue of the sloping surface 33, this causes a corresponding adjustment of each rod .34 in afiradial direction.
During-the time when each Wedge .30 is being acted on by thejsetting member 2, the end of the corresponding rod34-engagesa cam surface seenin Figure 1 which forcestherod outwardly against the efiect Of the spring '37-, thus relieving the pressure on the surface :33 and allowingthe wedge 30 to be freely adjusted. The drum 81' rotates in a counter-clockwise direction and as soon as each rod 34 passes the end of. the cam 45 it is released to-bear against the sloping surface 33. Each rodthus takes up a radial position determinedby the setting memher 2 and the pressure .of the rod .against the surface 33 35 ,elfectively locks both the .rod3l, and the wedge 30.
0 -..rods in a circumferential direction tobe made smaller without unduly crowding them together. In order to ensure that a given position of aiwedge-30 produces a correspondingidisplacement of its rod .34 regardless of whether it is inthe line 46 or 47, alternate wedges 30 45 have their sloping surfaces 33 displaced tothe left as seen at 33 at the .topof Figure 3. A corresponding wedge is shown in'fulllines at the bottom 9f Figure 3, while behind itawedge havingits sloping surface shown. as 33 is indicated in dotted lines.
As a're'sult of this, all ofthe rods 34 leavingthe end ofthelcam surfacedfi are caused to projectrajdially by anamount. dependingon the position of thesetting membet-2 and hence depending on the thicknessof the sliver passingbetweenthe-measuring rollers A; The frods and 1the wedges, which are locked together as described above,..then..pass in a counter-clockwise direction for approximately three quarters ofa revolution. The, time taken in this movement represents the time delay; which it'is required to introduce .between themeasurernent of 0 the itl'lickIlBSS .of the sliver and the corresponding adjustmentof the. draft of. the drawing headwhich is effected by means f of theiitransmitter. 3. This'iimeintert'al will,
.of bourse, be determined by the speed offrotationlof, the drum .31 which is. related directly to the sp'eed'of the drawing head. a
- flh'e rods .34 arrive at/the transmitter roller 3 and displace the latt'erbyfan amou'ntdepending on their setting, andhence onithe. thickness .of the sliver Whichthas been measured. Since the transmitter isin the 'formpf O a'r ollerthe wear-on. the tips of the rods is negligible resettihg m mber"s i which restore them to theif datum Y5 rssi :A smi en Fi u e the? me er W a flared mouth to allow for the maximum displacement of the wedge members. The need for the corresponding flared mouth on the setting, member 2 is to ensure that the wedges 30 enter this mouth even when the setting member 2 is displaced to one of its extreme positions indicated by the dotted lines 25' and 26'.
Displacement of the transmitter roller 3 by the rods 34 causes corresponding displacement of a bellcrank lever 50 pivoted at 51. This is connected at its lower end 52 to a link 53 connected in its turn at its far end 54 to a lever 55 pivoted at 56.
The lever 55 controls the setting of a variable-ratio cone drive comprising a pair of oppositely disposed cones 60 and 61. The upper end of the lever 55 is fitted with a fork comprising prongs 62 located on opposite sides of a belt 63 passing around the cones 60 and 61. These cones form one stage in a gearbox 65, the details of which are not shown but which has its input applied by way of a gearwheel 66 and its output taken from a further gearwheel 67. Accordingly as the belt 63 is adjusted along the cones 60 and 61 so the ratio of the gearbox 65 is adjusted to provide corresponding control of the draft of the drawing head. The drawing head is not illustrated but in practice it is convenient to drive the drafting rollers at a substantially constant speed and to drive the feed rollers from the drafting rollers through the gearbox 65. Consequently any variations in thickness of the sliver 16 are reflected as compensating variations in the speed of the feed rollers which tend to improve the levelness and quality of the sliver.
1. In combination with a textile sliver drafting machine, means for measuring the size of textile slivers fed into said machine, and a time-delay mechanism for controlling the draft of said textile slivers in said machine in accordance with variations in the size of sliver entering the drawing head of said machine, said mechanism comprising a plurality of slidable members mounted on a rotatable carrier, each of said members slidable in a direction axially of the path of rotation of said carrier, each of said slidable members having a surface sloping at an angle to the direction of sliding, setting means for positioning said members relative to said carrier spaced from said carrier and connected to said sliver measuring means, the spacing of said setting means from said carrier being responsive to variations in the size of the sliver in said measuring means, said setting means engaging and slidably positioning each of said members relative to said carrier, a plurality of rods on said carrier and projecting radially therefrom, each of said rods engaging a sloping surface of a. slidable member, each of said rods movable in a direction radially from said carrier in response to the sliding movement of said sloping surface of said slidable member, means for locking said rod in engagement with said sloping surface after said member has been slidably positioned on said carrier by said setting means, transmitting means for controlling the draft of said drawing head of said machine, said transmitting means disposed adjacent said carrier and successively engaged by the radially extending end of each of said rods traveling about said path of rotation, and means for subsequently disengaging said locking means to again permit movement of said slidable member relative to said rod and said carrier.
2. The apparatus as defined in claim 1 wherein each of said rods has a centrally cut-away portion defining a shoulder, said shoulder engaging the sloping surface of its corresponding slidable member.
3. The apparatus as defined in claim 1 wherein said means for locking each of said rods in engagement with said sloping surface is a compression spring on the inwardly extending end of said rod.
4. The apparatus as defined in claim 3, wherein said means for disengaging said locking means includes a cam surface mounted on said carrier and positioned to engage the inner end of each of said rods after each of said rods has moved past said transmitting means in the said path of rotation, said rods moving radially outwardly relative to said carrier and said sloping surfaces where said inner ends thereof engage said cam surface.
5. Apparatus as defined in claim 4 including a fixed resetting member adjacent said carrier at a point in its path of rotation between said disengaging means and said setting means, said resetting member positioned to engage the ends of said sliding members and center said members relative to said carrier in a datum position.
6. Apparatus as defined in claim 1 wherein said rods are alternately staggered in a pair of rows about the periphery of said carrier.
7. The apparatus as defined in claim 1 wherein the portion of said transmitting means engaged by the outer end of each rod is a roller.
8. Time-delay mechanism for automatically controlling the draft of a drawing head on a textile sliver drafting machine in accordance with variations in the size of the sliver entering said drawing head, said mechanism comprising a rotatabl carrier, a plurality of axially slidable members mounted on said carrier and projecting laterally from each side thereof, each of said slidable members having a surface sloping at an angle to its direction of sliding, a plurality of rods mounted on said carrier and projecting radially therefrom, means for raising each of said rods into engagement with the sloping surface of a corresponding slidable member, said rods movable radially of said carrier in accordance with the axial positioning of the corresponding sloping surface of the slidable members, means for measuring the size of the sliver to be fed into the drawing head of the machine, setting means spaced from said carrier and connected to said sliver measuring means, the spacing of said setting means from said carrier being directly responsive to the variations in the size of the sliver being measured, setting means engaging the laterally projecting ends of said members and slidably positioning said members on said carrier, the corresponding rod engaging the sloping surface of said member being simultaneously positioned radially on said carrier, the radial position of each of said rods corresponding to a definite size of sliver being fed into the drafting machine whereby means engaging the ends of said projecting rods at a predetermined point on the path of rotation of said carrier automatically adjust the draft of the drawing head of the machine at the time when the corresponding measured portion of sliver enters the head.
References Cited in the file of this patent UNITED STATES PATENTS 2,633,913 Morrow et al Apr. 7, 1953 2,681,475 Raper June 22, 1954 2,746,093 Raper May 22, 1956 2,810,936 Altenburger Oct. 29, 1957 FOREIGN PATENTS 710,957 Great Britain June 23, 1954