CONTROL DEVICE FOR SETTING TWO OR MORE TOOL UNITS IN A MACHINE, ESPECIALLY A VENETIAN BLIND PRODUCTION MACHINE

Abstract: A control device for adjusting two or more tool units (3) in a machine, especially a Venetian blind production machine, comprises a number of series-con­ nected setting screws (10-14) and gear units (15-19) for proportionally displacing said tool units along the machine bed (2) during operation of the machine by means of a drive motor (21).

Description: On many machines, especially Venetian blind production machines, a number of tool units must be set in different positions along a machine bed. In some cases, it is desired that these tool units should be movable proportionally relative to one another along the machine bed, such that they can be placed in optionally selectable and yet relatively proportional positions along the machine bed. One instance of this requirement is the Venetian blind production machine which constitutes the subject matter of the European Patent EP-B-0,182,805 and which comprises a feeding device for supplying from a supply reel at least one metal strip intermittently in the longitudinal direction of the metal strip through a number of ladder tapes, and a punching station with means for punching lift cord holes in the free end portion of the metal strip before this end portion is inserted in the ladder tapes, as well as a separating station for separating from said free end portion of the metal strip the individual Venetian blind slats inserted in the ladder tapes. The punching station of this Venetian blind production machine has at least two groups of punching tools for simultaneously punching lift cord holes in at least two successive Venetian blind slats, said separating station having at least a corresponding number of separating punches for simultaneously separating Venetian blind slats for the same number of simultaneously produced Venetian blinds. For readjustment of such a Venetian blind production machine for different slat lengths, the different tools must be set in exact positions along the machine bed. This operation is time-consuming, and errors are easily made. If the punching of lift cord holes takes place in a machine section ahead of the threading tools, the setting operation will be far more complicated and even more time-consuming. The present invention aims at providing a control device by which two or more tool units in a machine, especially a Venetian blind production machine, can be set in different optionally selectable and relatively proportional positions along a machine bed. The characterising features of the invention are stated in the main claim. The control device according to the invention thus comprises a number of series-connected setting screws and gear units for proportional displacement of the tool units along the machine bed during operation by means of a drive motor. Especially preferred embodiments of the invention are defined in the sub-claims. The invention will be described in more detail hereinafter, reference being had to the accompanying drawings illustrating two embodiments of a device according to the invention. In the drawings: Fig. 1 is a schematic lateral view of a Venetian blind production machine; Fig. 2 is a top plan view of parts of a control device included in the machine; Fig. 3 illustrates, on a larger scale, the area III in Fig. 2; Fig. 4 is a schematic section on line IV-IV in Fig. 1; Fig. 5 is a schematic section on line V-V in Fig. 1; Fig. 6 is a schematic top plan view on line VI-VI in Fig. 1 ; and Fig. 7 illustrates a further embodiment of the device according to the invention, the device being illustrated schematically in accordance with Fig. 2. The embodiment illustrated in the drawings of the device according to the invention is used for a Venetian blind production machine which comprises a frame 1 having an elongate machine bed 2 along which a number of tool units 3 can be clamped in desired positions paying regard to the Venetian blind production concerned. The different units are interconnected by a main shaft 4 which is driven by a motor (not shown) accommodated in a housing 5. At the infeed end of the machine, a supply reel 6 is mounted for supplying a metal strip 7 which is fed in the longitudinal direction of the machine in a manner explained in detail in the above-mentioned European patent EP-B-0,182,805 which is included by reference. For particulars in this respect, reference is therefore made to that publication. During operation of such a Venetian blind production machine, it is desired that the different tool units 3 should be movable simultaneously and proportionally relative to one another along the machine bed 2. In prior art machines of this type, the different tool units were individually displaceable and clampable against the machine bed in desired positions along the bed. Adjustment therefore was time-consuming. In a device according to the present invention, two or more tool units 3 of the machine can be set by means of series-connected setting screws 10-14 and gear units 15-19, the latter being mounted in carriages 20 slidable along the machine bed. The number of tool units may be optionally varied. Figs 2 and 3 illustrate a first setting screw 10 which, at its left-hand end as shown in the drawing, is connected with a drive motor 21. The screw 10 engages with a nut 22 fixedly connected with the housing 23 of the gear unit 15. The screw then extends through the hub of a gear wheel 24 of the gear unit 15. The gear wheel is nonrotatably but displaceably connected with the screw 10 by means of a wedge 25 which engages with a longitudinal keyway extending along the entire control length of the screw 10. The gear wheel 24 is mounted in the housing 23 by means of ball bearings 28 and engages with a second gear wheel 27 which also is mounted in the housing 23 by means of ball bearings 28. The gear wheel 27 is nonrotatably connected, by means of a wedge 29, with the succeeding setting screw 11 which is nonrotatably locked to the gear wheel 27 by means of a pin 30. Since the screws 10 and 11 are interconnected by means of two meshing gear wheels, the screws 10 are oppositely threaded. The housings 16, 17, 18 and 19 are designed in accordance with the housing 15 and need not therefore be described in detail. It is essential that the screws are oppositely threaded two and two. However, if each gear unit is provided with an additional gear wheel, the screws 10, 11 may be threaded in the same direction. The preferred gear ratio in the embodiment illustrated is 1:1, but for some applications other gear ratios may be desired for specific tool units or for all tool units. Adapting the gear ratio to existing requirements is professional routine. As will appear from Figs 4 and 5, the carriages 20 and the machine bed 2 are so wide that six screws can be mounted side by side and with the same centre distances. In the embodiment illustrated, however, only five screws are used. Figs 4 and 5 also show that the main shaft 4 of the machine has a longitudinal keyway 31 engaged by a wedge (not shown) on each tool unit 3 for operating a tool mounted therein. Figs 1 and 4-6 show a number of supports 32 which are mounted along the machine bed 2 and can be automatically folded up and down during movement of the carriages 20 along the machine bed. The supports are pivotally connected with the machine bed by means of a pivot pin 33 and are spring-biased, by means of a spring mechanism (not shown), in counterclockwise direction (Figs 4 and 5), which means that they are biased upwardly to the position shown in Fig. 5. Fig. 4 shows one of these supports in folded-down position. When the carriages 20 are moving along the machine bed, the supports are automatically folded down by means of a cam 34 which is mounted on the carriage 20 and formed with an oblique cam surface 35 adapted to engage with a corresponding cam surface 36 on each support 32. In this manner, the supports 32 will be folded up and down during movement of the carriages 20 along the machine bed. Fig. 7 illustrates a further embodiment of the device according to the invention. In this embodiment, the control device is used for two groups of tool units mounted on two sets of gear units 15-19 and 15′-19′ which are operated by a centrally positioned drive motor 21. In other respects, the device may have the same construction as described above in connection with the first-mentioned embodiment. For adjustment of the different tool units, the drive motor may be a manually operated source of motive power, such as a crank, or some other rotary type power source, such as an electric motor. For automatic operation, use can be made of an electric motor controlled by a computer or the like which in that case may be programmable to store data about different types of products that can be manufactured in the machine. As has been mentioned above, Fig. 7 shows how the control device according to the invention can be used for two groups of tool units arranged at both ends of a centrally positioned drive unit. A further possibility of using the control device for several sets of tools is to mount the tools side by side in each tool unit 3. This embodiment may be advantageous for example when it is desired, in the production of Venetian blinds, to punch and cut mounting rails and the like in the same machine which subsequently is to be used for punching and cutting of blind slats in the manner disclosed in for example the above-mentioned European patent EP-B-0,182,805. Similarly, each tool unit 3 may also comprise juxtaposed tools for different slat widths, for example 15 mm, 25 mm, 35 mm, 50 mm etc.

Claims: Control device for setting two or more tool units (3) in a machine, especially a Venetian blind production machine, said tool units being arranged in succession along the length of a machine bed (2) and being settable in different optionally selectable and relatively proportional positions along the machine bed (2), characterised in that the device comprises a series of setting screws (10-14) and gear units (15-19), said setting screws(10-14) and said gear units (15-19) being arranged in series after one another and associated each with one tool unit (3) and being connected with a drive motor (21) for operation of the series of setting screws and gear units; that each setting screw (10-14) has a longitudinal keyway (26); that an input driving member (24) in the associated gear unit (15-19) operated by the setting screw is nonrotatably connected with a wedge means (25) which engages with and is displaceable in the longitudinal direction of said keyway; that the gear box has an engaging means (22) which engages with its driving setting screw (10-14) and is rigidly connected with the housing (23) of said gear unit; and that the output driving member (27) of the gear unit is nonrotatably connected with the succeeding setting screw for operation thereof, such that the tool units are proportionally displaceable along the machine bed (2) by the rotation of the setting screws. A device as claimed in claim 1, characterised in that the engaging means (22) is a nut (22). A device as claimed in claim 1 or 2, characterised in that the input and output driving members (24, 27) of said gear unit (15-19) are gear wheels. A device as claimed in claim 1, 2 or 3, characterised in that the gear ratio of the said gear unit (15-19) is 1:1. A device as claimed in any one of the preceding claims, characterised in that it comprises two mirror inverted series of setting screws and gear units connected with and operated by a common drive motor positioned therebetween. A device as claimed in any one of the preceding claims, for use in a Venetian blind production machine, characterised in that it comprises a number of supports (32) mounted along the machine bed (2) and pivotally connected with the machine bed and spring-biased in the upward direction; and that each gear unit (15-19) has an operating cam (34, 35) which, upon displacement of the gear unit along the machine bed, is movable into engagement with a cam surface (36) provided on each support and adapted to cause the support to drop as the gear unit goes past it.

Inventors: NILSSON, BERNDT ROLAND
Applicants: AKTIEBOLAGET SANI-MASKINER
Application year: 1989
Main classification: E06B9
IPC codes: B23Q39, E06B9, B23Q5