|Title of Invention||
KNITTING MACHINE ESPECIALLY WARP KNITTING MACHINE
|Abstract||ABSTRACT The knitting machine has a main drive (16) for at least one needle bar of a knitting-needle row as well as a central control apparatus (120) with an input device (122) for fixing the characteristic data of the knitted fabric to be produced. To improve the control, each drive (16,28,33,35,63a,63b,63c,63d) of individual components (15,22,32,34,44a,44b,44c,44d) is provided with an indi¬vidual intelligent control unit (163,283,333,353, 63a3, 63b3,63c3,63d3) for receiving and running off the associ¬ated programme module of the control apparatus (120). The drives are connected to one another and synchronized via a common desired-value clock generator line (130), one drive (16) being designed as a main drive and an associ¬ated clock generator (164) being designed as a desired-value clock generator. ■J'|
The present invention relates to a knitting machine, especially a warp knitting machine.
A knitting machine of the type mentioned in the introduction is known from DE-A-42 38 600. This knitting machine contains a central control unit and individual intelligent control units for the individual assemblies. The individual control units are each equipped with a clock generator. The connection between the central control unit and the individual control units is made via an external BUS. The programme modules necessary for the relevant assembly and intended for the knitted fabric to be produced are run off on the individual control units. One disadvantage is that the coordination of the separate individual control units takes place via the central control unit, to which the signals from the individual clock generators are transmitted, processed and returned as control signals to the individual control units. For this purpose, the central control unit contains an additional BUS driver. This design not only makes the control relatively complicated, but in particular, also limits the speed of the data exchange and of the control of the assemblies.
The object of the invention is to improve a knitting machine of the type mentioned in the introduction.
Accordingly the present invention provides a knitting machine, especially a warp knitting machine, comprising a central control apparatus containing a computer and having an input device for fixing the characteristic data of the knitted fabric to be produced, and a central control unit which is connected via a line to individual drives for assemblies of the knitting machine, each drive
having an individual intelligent control unit for receiving and running off an associated schedule module from the central control apparatus and, in each case, a clock generator for determining the working position of the assembly, characterized in that the drive of one assembly is designed as a main drive and the associated clock generator is designed as a desired-value clock generator, the clock generator being connected directly to the individual control units of all the assemblies via a desired-value clock generator line, the remaining clock generators being connected as auxiliary clock generators in each case to the associated drive designed as an auxiliary drive wherein a pattern schedule input on the central control apparatus is workable on the individual control units independently of a central control unit of the central control apparatus.
Since each drive has an individual intelligent control unit for receiving and running off an associated pro¬gramme module of the control programme of the central control apparatus and the drive of an assembly is designed as a main drive with an associated clock gener¬ator as a desired-value clock generator, the drives of all the assemblies being connected to one another via a desired-value clock generator line, substantial simplifi¬cation and greater flexibility and adaptability of the drives, especially of the auxiliary drives, are obtained. It is thereby possible to load the individual control units in each case with the associated programme module directly when the knitting machine is switched on, so that all the drives can be regulated autonomously, that is to say without communication with the central control apparatus, and therefore more quickly than hitherto and can thus react to changes in rotational speed of the main drive in a simpler, faster and more accurate manner. As a result, the central control apparatus is also no longer required and is free for the input of new control pro¬grammes. The speed and efficiency-of the control of the knitting machine are appreciably improved. Each programme module can therefore be set individually to the function to be performed, so that complicated transitional curves, compensating curves and the like are not necessary. This results in an appreciable improvement in the control of the knitting machine.
Advantageous embodiments of the knitting machine are described in Claims 2 to 9.
There are various possibilities for designing the desired-value clock generator. According to Claim 2, it is advantageous to provide, as a desired-value clock generator, a signal generator responding to the angular position of a main drive-shaft.
The design of the knitting machine according to Claim 3, according to which each auxiliary drive is provided with a synchronous motor, is advantageous. Such a synchronous motor is advantageously connected via a
reduction gear to the particular assembly to be driven which, for example, is a guide bar. High racking forces, for example two kiloponds per yarn, for a mean racking of 108 mm can thereby be achieved, or else, in the case of low yarn forces, long racking distances can be achieved, such as is necessary, for example, for the full weft over the entire length of the knitting machine.
According to Claim 4, the main drive is prefer¬ably equipped with an asynchronous motor.
According to Claim .5, the knitting machine is preferably equipped with at least two guide bars which, in particular, can be arranged in a highly flexible and space-saving manner because each has its own auxiliary drive. It is thus possible to provide the drive at the right-hand end for one guide bar and the drive at the left-hand end for the other guide bar, thereby resulting in a space-saving arrangement which, moreover, is restricted only to the ends of the guide bar, so that the remaining space can be utilized for further components and/or for access to the knitting machine.
The same advantages also arise in the case of the arrangement of a full-weft device according to Claim 6 and/or of a part-weft device according to Claim 7. A design according to Claim 8 is especially advantageous here, since the revolving member can be used individually both for part wefts and for full wefts, while the amount of racking can be changed by means of the individual control unit without mechanical actions.
A development according to Claim 9 is also especially advantageous, resulting in a highly effective draw-off device which can be set in an optimum manner and which, once again, is highly space-saving, by virtue of which either space is available for other components and/or access to the knitting machine is improved.
The auxiliary drives for the individual assem¬blies or assembly groups allow an individual flexible control of the individual assemblies or assembly groups, in particular of the guide bars, as well as the coordination of the yarn guidance with the knitting-
needle movement. The type of weave, the stitch size and the force profile can thereby be optimized, without the knitting machine having to be converted. For knitting machines with high gauges and therefore long racking movements, appreciable advantages are afforded by means of the auxiliary drives for the individual assembly groups, since, for example in the case of a mechanical control of the guide bars, the machine would have to be operated at a very high outlay.
The control according to the invention is especially suitable particularly for coarse knitting machines, that is to say for knitting machines for coarse knitted fabrics, since, as a rule, such machines are slow-running (100 revolutions per minute) and work with high needle gauges of, for example, one needle every two centimetres, in which long racking and swinging movements have to be executed. In knitting machines conventional hitherto, the gauges are substantially finer, for example six needles per centimetre, and the racking strokes correspondingly shorter at higher speeds of, for example, 500 to 2000 revolutions per minute.
The concept according to the invention is of great advantage particularly for double-section knitting machines, which is very important for practical use. Previous double-section knitting machines offered on the market have either the drive or drive elements for the motor force and/or the guide bars mounted centrally in the knitting machine, as a result of which the fabric draw-off has to be guided around the drive elements in a complicated manner and on account of which, moreover, access to the knitted fabric in the region of the draw-off is poor. This is restricting, on the one hand, when the fabric to be knitted is being drawn in, but also during inspection and production and when the knitted fabrics are being drawn off.
In contrast, the auxiliary drives according to the invention for the guide bars can be mounted on both sides of the knitting machine by virtue of the concept of the individual drives, so that no drives or drive
elements protrude disruptively into the draw-off region of the knitted fabric. The fabric to be knitted is consequently readily accessible for draw-in when the knitting machine is started, thus increasing the operat¬ing reliability of the knitting machine and making inspection and draw-off of the knitted fabrics easier. In particular the simplification of the fabric draw-off is especially substantial, since the draw-off rollers can thereby be led very close to the knitting point, thus increasing the operating reliability, that is to say accurate stitch formation and therefore stitch quality.
Exemplary embodiments of the knitting machine according to the invention are described in more detail below by means of diagrammatic drawings in which: Figure 1 shows a warp knitting machine in a view of the
longitudinal side; Figure 2 shows the knitting region of the warp knitting
machine of Figure 1 in the section II-II of
Figure 1 and on a larger scale; Figure 3 shows a block diagram of the control of the
warp knitting machine; and Figure 4 shows a flow chart for the interaction of the
assemblies during the production of a knitted
Ways of implementing the invention
Figures 1 and 2 show, as a preferred exemplary embodiment of a knitting machine according to the inven¬tion, a double-section Raschel machine, that is to say a warp knitting machine with two knitting-needle rows 2,4 which are each arranged and drivable in a known way by means of needle bars so as to swing up and down on rocker levers 6,8 mounted in the machine stand 5. Thus, these rocker levers 6,8 are driven, for example, via connecting rods 10 cooperating with rocker levers 12 which, at their free ends, cooperate with cam discs 14 on a main shaft 15 driven by a main drive 16. The knitting-needle rows 2,4 are arranged on both sides of knock-over bars 18, between which the knitted fabric 20 is drawn off by means of a
draw-off device 22. The latter consists of two draw-off rollers 24,26, which are driven by an auxiliary drive 28, and of a pressure roller 30.
Each knitting-needle row 2,4 is thus assigned a part-weft device 32 with an auxiliary drive 33 or a full-weft device 34 with an auxiliary drive 35. The part-weft device 32 (omitted for the sake of clarity in Figure 1) has a guide bar 36 and yarn guide 38 which in each case rack only over a portion of the knitting-needle rows 4. The full-weft device 34 contains a revolving member 40 which is designed as a toothed belt and is driven to and fro over the entire knitting-needle row 2 by means of the auxiliary drive 35 and to which a yarn guide 42 is fastened for executing the full weft.
Four further guide bars 44a,44b,44c,44d with yarn guides 48 for feeding warp yarns 46 via upper guide members 47 are arranged above the knitting-needle rows 2,4. The guide bars 44a,44b,44c,44d contain, on both sides, two parallel carrier bars 50, by means of which they are mounted, so as to be capable of being racked in the longitudinal direction, in rockers 52 which are themselves fastened to a pivotable shaft 54 mounted in the machine stand 5. The shaft 54 is provided in a way known per se with a drive lever 56, on which is articu¬lated a connecting rod which is connected to a further pivotable lever 60 in the machine stand and cooperating with a cam disc 62 on the main shaft 15 driven by the main drive 16. The guide bars 36,44a,44b,44c,44d are designed at least essentially identically, although auxiliary drives 35,63a,63b,63c,63d serving for racking in the longitudinal direction can be arranged on any sides, for example alternately now at the right-hand end and now at the left-hand end from guide bar to guide bar. The guide bars can be designed differently, but are preferably of basically identical design, whi-at individ¬ual or all guide bars can be equipped with at least one auxiliary guide bar.
Figure 3 shows a block diagram of the control of th« above-described warp knitting machine together with
its assemblies. The warp knitting machine contains a central control apparatus 120 with an input device 122, on which the characteristic data of the desired pattern for the knitted fabric to be produced can be entered, for example by means of a keyboard, a floppy-disc running mechanism or the like. A connected central control unit 124 processes the data and transmits them via a communi¬cation line 126 to the individual parallel-connected drives, that is to say to the main drive 16, the auxili¬ary drives 63a,63b,63c,63d for the guide bars 44a,44b,44c,44d, the auxiliary drive 33 for the part-weft device 32, the auxiliary drive 35 for the full-weft device 34 and the auxiliary drive 28 for the draw-off device 22. All the drives are connected to a feeder line 128 for the supply of energy. All the drives are designed autonomously and identically, so that the subscripts to the respective reference symbols denote identical parts in each case, specifically;
Subscript 1 : Motor
Subscript 2 : Line
Subscript 3 : Individual control unit with
Subscript 4 : Clock generator
Subscript 5 : Clock generator line.
The following design is thus obtained for the main drive 16. A motor 16j^ is connected via a line 162 to an individual control unit 163 which contains a computer and which runs off autonomously a programme module supplied by the central control apparatus 120 via the communication line 126. For this purpose, the motor 16x has connected to it a clock generator 164 which responds to the angular positions of the main drive shaft 15 of the main drive 16 and which is connected to the indivi¬dual control unit 163 via a clock generator line 165. In the present example, the clock generator 164 of the main drive serves as a desired value for the auxiliary drives, so that the clock generator line 165 of the main drive is connected in parallel to all the auxiliary drives 63a, 63b, 63c, 63d,33, 35,28 via a desired-value clock gener-
ator line 130 and serves for coordinating the run-off of the programme modules on the auxiliary drives by means of the desired value predetermined by the clock generator 164 of the main drive 16. The auxiliary clock generators 63a4,63b4,63c4,63d4,334,354,284 of the various auxiliary drives are connected via corresponding clock generator lines 63a5,63b5,63c5,63d5,335,355,285 to the respective individual control units 63a3,63b3, 63c3, 63d3, 333,353,283 and serve for recording the actual state of each auxili¬ary drive which is then compared with the desired value of the main drive and correspondingly adapted by means of the respective individual control unit of the auxiliary drive. When the warp knitting machine is switched on or at the start of the programme run from the central control apparatus 120 to the individual control unit 163 of the main drive 16 and the individual control units 63a3,63b3,63c3,63d3,333,353,283 of the individual auxili¬ary drives 63a,63b,63c,63d,33,35,28, the individual programme modules are loaded and are run off indepen¬dently there. Each drive can thereby be controlled auton¬omously with equal entitlement and therefore more rapidly. There is no need for any communication between the central control apparatus and the other individual control units of the remaining drives. Moreover, after the programme modules have been unloaded, the central control apparatus 120 is free to enter the characteristic data for producing another knitted fabric.
Whilst the auxiliary drives 63a, 63b, 63c, 63d, 33, 35 of the guide bars 44a,44b,44c,44d, of the part-weft device 32 and of the full-weft device 34 work absolutely in synchronism, the auxiliary drive 28 of the draw-off device 22 can be operated at a positively or negatively deviating rotational drive speed, so that the draw-off device can be adapted to the properties of the particular knitted fabric to be produced. A warp knitting machine of the present type has, for example, the following data:
Operating speed 10 to 120 rpm
Crawling speed 0.1 to 5 rpm
Draw-off stitch width 4 to 50 mm/rev.
Draw-off drop 0 to 100 %
Needle gauge 14, 18, 22 mm
Production length 1 to ram
For each knitted fabric to be produced and for the entire pattern report, for example a specific in¬struction list (computer programme), which is not shown in any more detail here, is stored in the central control apparatus 120. When the knitting machine is started, such an instruction list is loaded as a programme module in the individual control units of the individual auxiliary drives and is run off there, the coordination of the individual auxiliary drives with the main drive 16 being ensured by the desired-value clock via the desired-value clock generator line 130. Figure 4 shows, in a flow chart, the interaction of the rear needle bar with the rear needle row 2, the front needle bar with the front needle row 4, of the pivoting movement 132, that is to say the motor force of the guide bars 44a,44b,44c,44d, and the racking of the guide bars 44a,44b,44c,44d as a function of the rotational movement of the main shaft 15 for two revolutions of the latter. The racking of the guide bars is given in part strokes of plus/minus units, one unit corresponding in each case to 1 needle gauge.
The warp knitting machine illustrated is highly suited to the production of coarse knitted fabrics with, for example, coarse yarns of up to 4800 tex. Thus, for example, nets and mats for the most diverse purposes can be produced by means of the warp knitting machine, such as, for example, nets for climbing frames in play areas, safety nets of the most diverse kinds, mats and the like, in each case for a wide variety of intended uses.
LIST OF REFERENCE SYMBOLS
2 Knitting-needle row
4 Knitting-needle row
5 Machine stand
6 Rocker lever
8 Rocker lever
10 Connecting rod
12 Rocker lever
14 Cam disc
15 Main shaft
16 Main drive
18 Knock-over bars
20 Knitted fabric
22 Draw-off device
24 Draw-off roller
2 6 Draw-off roller 28 Auxiliary drive
3 0 Pressure roller
32 Part-weft device
33 Auxiliary drive
34 Full-weft device
35 Auxiliary drive
36 Guide bar
3 8 Yarn guide
40 Revolving member
42 Yarn guide
44a Guide bar
44b Guide bar
44c Guide bar
44d Guide bar
46 Warp yarn
47 Guide member
48 Yarn guide
50 Carrier bar
56 Drive lever
58 Connecting rod
62 Cam disc
63a Auxiliary drive
63b Auxiliary drive
63c Auxiliary drive
63d Auxiliary drive
120 Central control apparatus
122 Input device
124 Central control unit
126 Communication line
128 Feeder line
130 Clock generator line
132 Pivoting movement (motor force)
WE CLAIM :
1. Knitting machine, especially a warp knitting machine, comprising a central control apparatus (120) containing a computer and having an input device (122) for fixing the characteristic data of the knitted fabric (20) to be produced, and a central control unit (124) which is connected via a tine (126) to individual drives (16, 28, 33, 35, 63a, 63b, 63c, 63d) for assemblies (15, 22, 32, 34, 44a, 44b, 44c, 44d) of the knitting machine, each drive (16, 28, 33, 35, 63a, 63b, 63c, 63d) having an individual intelligent control unit (I63, 283, 33a, 353, 63a3, 63b3, 63C& 63d3) for receiving and running off an associated schedule module from the central control apparatus (120) and, in each case, a clock generator (164, 284, 334, 354, 63a4, 63b4, 63c4, 63d4) for determining the working position of the assembly, characterized in that the drive (16) of one assembly (15) is designed as a main drive and the associated clock generator (164) is designed as a desired-value clock generator, the clock generator (164) being connected directly to the individual control units (I63, 283, 333, 35s, 63a3, 63b3, 63C3, 63d3) of all the assemblies via a desired-value clock generator line (130), the remaining clock generators being connected as auxiliary clock generators (284, 334, 354, 63a4, 63b4, 63c4, 63Q%) in each case to the associated drive designed as an auxiliary drive (28, 33, 35, 63a, 63b, 63c, 63d) wherein a pattern schedule input on the central control apparatus (120) is workable on the individual control units (163, 283, 333, 353, 63a3, 63b3, 63c3, 63d3) independently of a central control unit (124) of the central control apparatus (120).
2. Knitting machine according to claim 1, wherein the desired-value clock generator (164) is designed as a signal generator responding to the angular position of a main shaft (15) of the main drive (16).
3. Knitting machine according to claim 1 or 2, wherein the motor (281, 33t, 35i, 63aj, 63bi, 63cl5 63dj) of each auxiliary drive (28, 33, 35, 63a, 63b, 63c, 63d) is designed as a synchronous motor.
4. Knitting machine according to any one of the preceding claims, wherein the motor (16i) of the main drive (16) is an asynchronous motor.
5. Knitting machine according to one of claims 1 to 4, wherein it has at least two guide bars (32,44a, 44b, 44c, 44d) each with its own auxiliary drive (33, 35, 63a, 63b, 63c, 63d), the auxiliary drives of the guide bars being arranged preferably alternately on the left or on the right.
6. Knitting machine according to any one of the preceding claims wherein, at least one full-weft device (34) extends over the entire length of the knitting-needle row (2,4) and has its own auxiliary drive (35).
7. Knitting machine according to any one of the preceding claims, wherein at least one part-weft device (32) cooperates with the knitting-needle row (2,4) and has its own auxiliary drive (33).
8. Knitting machine according to claim 6 or 7, wherein the weft device (32, 34) has a revolving member (40) preferably a driven toothed belt, which
revolves over the entire working width and is driven by the auxiliary drive (33,35) and on which a yarn guide (42) is arranged.
9. Knitting machine according to any one of the preceding claims, wherein a
draw-off device (22) with its own auxiliary drive (28) is provided, the
draw-off speed of which can be set preferably independently of the main
10. Knitting machine substantially as herein described with reference to the
|Indian Patent Application Number||1899/MAS/1996|
|PG Journal Number||30/2009|
|Date of Filing||29-Oct-1996|
|Name of Patentee||M/S. TEXTILMA AG|
|Applicant Address||SEEATRASSE 97, CH-6052 HERGISWIL|
|PCT International Classification Number||D04B27/26|
|PCT International Application Number||N/A|
|PCT International Filing date|