GB2053295A

GB2053295A - Control box for a positioning drive of a sewing machine

Info

Publication number: GB2053295A
Application number: GB8019768A
Authority: GB
Original assignee: Frankl and Kirchner GmbH and Co KG
Current assignee: Frankl and Kirchner GmbH and Co KG
Priority date: 1979-06-21
Filing date: 1980-06-17
Publication date: 1981-02-04
Also published as: ES8103217A1; FR2459319A1; BR8003878A; PT71439A; JPS565691A; IT8022835A0; DE2924932A1; ES492663A0; IT1131335B

Abstract

A control box (1) for a positioning drive for an industrial sewing machine contains an actuating device for a control means (3) which supplies control signals which differ in dependence on the position of a switching element and further circuit devices, which follow the control switch, for processing these control signals. In order to make it possible to separate the actuating device from the control box (1) at will and with little effort, the actuating device is arranged in a separate housing (6) which is integrated detachably into a recess (5) in the control box (1). The control box (1) and the housing (6) may be electrically connected by a conductor (16) or the control box (1) and the separate housing (6) may be connected electrically by a plug and socket means or control means (3) may be mounted in the box (1) proper and the housing (6) connected thereto by a mechanical cable. <IMAGE>

Description

SPECIFICATION Control box for a positioning drive The invention relates to a control box for a positioning drive, particularly for an industrial sewing machine and containing an actuating device for a control means, such as a switch, which produces control signals that differ in dependence on the position of a switching element, the control means being connected to further circuit devices which process the control signals.

It is known to employ so-called external actuating units with positioning drives for industrial sewing machines. Such external actuating units are normally required where the positioning drive, which is mounted in the normal manner below the table top of a sewing machine, is used rotated through 1 800 in the horizontal plane. In such a case the actuating unit arranged in the control box comes far outside the range of the foot of a machine operator. Similar problems occur if sewing machine tables are constructed to be adjustable in all directions. In addition, with automatic sewing systems in which an industrial sewing machine is only a part of such an automatic system, external actuating devices are used because the workplace of the operator is often at a considerable distance from the place where the positioning drive is mounted.

It is known to construct such external actuating devices as separate, automatic devices which can be connected by a conductor to the control box.

In addition, designs have already been implemented in which actuating devices are removed from the control box and are assembled by means of special components to an actuating device which is separate from the control box. The opening in the control box which this creates must be covered by a separate component. This is very cumbersom and expensive for the user, with the consequence that often no use is made of the possibility of separating the operating position and the location of the positioning drive, which is often desirable for operational reasons.

For these reasons, the present invention seeks to provide a control box as outlined above which makes it possible to separate the actuating device from the control box at will with little effort.

According to the invention there is provided a control box for a positioning drive for an industrial sewing machine, containing an actuating device for a control means which produces control signals which differ in dependence on the position of a switching element, the control means being connected to further circuit devices for processing the control signals, wherein the actuating device is arranged in a separate housing which is detachably incorporated into the control box.

Thus the essence of the invention lies in making the actuating device independent with respect to the control box and, on the other hand, to integrate it into the latter in such a manner that it can be removed by simply loosening of mounting means without having to interfere with the mechanical or electrical design of the control box.

The connection between the actuating device, which can be removed from the control box, and the control box can be purely electrical.

In one embodiment of the invention, the separate housing of the actuating device is fitted into a recess of corresponding shape in the control box and in another embodiment the separate housing may also contain the control device, which may be a switch. An electrical connection may be provided between the actuating device and the control box, the connection including a plug and socket means between the separate housing and the control box. In an alternative embodiment of the invention, the actuating device and the control means are connected together mechanically for example by a flexible or "Bowden" (Trade Mark) cable.

Embodiments of the invention will now be described by way of example and with reference to the accompanying drawings, in which: Figure 1 shows a control box according to the invention and an actuating device, accommodated in a separate housing, in an exploded view.

Figure 2 shows an embodiment of the invention similar to the embodiment of Figure 1, having a different electrical connection between the separate housing and the control box, and Figure 3 shows an embodiment of the invention provided with a mechanical connection between the separate housing and the control box.

In all the drawings, a side part of a control box 1 is indicated which is flanged together with a drive as described in detail for example in the journal "BEKLEIDUNG UND WASCHE", Volume 7/1970, pages 466 two 470. This control box can be closed by means of a cover 2 which is arranged generally vertically. In the control box 1 circuit devices (not shown) for processing various control signals are arranged. These control signals come from a control means, for example a switch 3, a position sensor (not shown), for supplying control signals which represent the needle position of a sewing machine, and a speed sensor. These above-mentioned control signals are evaluated for the purpose of controlling the clutch and/or brake of a sewing machine drive. In addition, power supply devices such as a transformer can be arranged in the control box.

In a side wall 4 of the control box 1 a substantially cuboid recess 5 is formed into which a separate housing 6 of similar shape can be inserted which is mounted in an easily detachable manner in the recess by means of through bolts 7 engaging in corresponding threaded holes 8 in the recessed side wall area 9 which delimits the recess 5. As can be seen from the drawing, the outer wall 12 of the separate housing 6 rests flush with the side wall 4, that is to say the separate housing 6 is spatially fully integrated into the control box 1 when it is fully secured in position.

In the separate housing 6 an actuating device is arranged which is indicated schematically in the drawing and the actuating arm 10 of which is supported by means of the support shaft 11 in a corresponding hub in the front wall 12 of the housing 6. On the outer end of the support shaft 11 a lever 13 is mounted to rotate therewith on the outside, that is to say in front of the front wall 12. The free end of this lever 13 is provided with a ball pivot joint 14. This ball pivot joint 14 is part of a conventional angle hinge by means of which, for example, a rod is connected which leads to a pedal so that the lever 1 3 and thus the actuating arm 10, which is also joined to the support shaft 11 to rotate therewith, can be rotated by means of such a pedal.The actuating arm 10, in turn, is connected at its free end to a switching element 1 5 of the control switch 3 which is also arranged in the housing 6 in a stationary manner.

The control switch 3 is electrically connected by a control line 1 6 to the circuit devices in the control box 1. This spirally-wound control line 1 6 is accommodated in a trough-like duct 17 moulded into the back wall 18 of the housing 6 of the associated wall of the control box 1 when the separate housing 6 is screwed to the control box 1. Although not part of this invention, a description and representation of the actuating device comprising the actuating arm 10, the lever 13 and the control switch 3 can be found in German Patent Application P 29 13 861.2.

If, for reasons of space or for operating masons or merely for reasons of ease of operating, the actuating device must be arranged spatially removed from the control box 1, only the through bolt 7 need to be removed and the separate housing 6 and the actuating device detached from the control box 1 and mounted at a suitable or desired position. The mechanical or electrical configuration of the total system does not need to be interfered with.

The embodiment shown in Figure 2 differs from that of Figure 1 only in that the electric connection between the control switch 3, on the one hand, and the circuit devices in the control box 1, on the other hand, is made by a plug and socket connection when the housing 6 is attached to the control box 1. In this arrangement, a plug 19 is provided on the rear wall 18 of the housing 6 which is associated with a corresponding socket 20 in the associated wall 9 of the recess 5. When the housing 6 is screwed into the recess 5 of the control box 1, this simultaneously establishes the electric connection between the control switch 3 and the circuit devices in the control box 1.If the actuating device and the housing 6 is detached from the control box 1, the electric connection must be made by means of an appropriate control line which has plugs and sockets complementing the plug 19 and the socket 20.

The embodiment illustrated in Figure 3 differs from that of Figures 1 and 2 in that the control switch is arranged not in the separate housing 6 but in the control box 1. The actuating arm 10 of the actuating device is in this case joined to one end of the inner wire 21 of a flexible of "Bowden" cable, the flexible outer casing 22 of which, on the one hand, is fixed at one end in a thrust bearing 23 in the housing 6 and at the other end is fixed in a thrust bearing 24 in the control box 1. The other end of the inner wire 21 engages a movable part 25 which is connected to the switching element of the control switch. Here, too, a duct or similar means if formed either in the rear wall 1 8 or in the associated boundary wall of the recess 5 or in both walls, which serves to accommodate the cable and into which the cable is inserted when the housing is screwed to the control box 1.

The "Bowden" cable can have an appropriate length for use when the housing 6 and the actuating device are mounted separately from the control box 1. On the other hand, however, it can also be a short cable for use when they are mounted together and can then be replaced by another similar cable of appropriate length when the housing 6 and the actuating device are mounted separately from the control box.

Claims

A control box for a positioning drive for an industrial sewing machine, containing an actuating device for a control means which produces control signals which differ in dependence on the position of the switching element, the control means being connected to further circuit devices, for processing the control signals, wherein the actuating device is arranged in a separate housing which is detachably incorporated into the control box.
2 A control box according to claim 1, wherein the separate housing is accommodated in a matching recess of the control box.
3. A control box according to claim 1 or claim 2, wherein the control means is also arranged in the separate housing.
4. A control box according to claim 3, wherein an electric plug and socket connection is provided between the separate housing and the control box.
5. A control box according to claim 3, wherein an electrical conductor is provided between the separate housing and the control box.
6. A control box according to claim 5, wherein a duct or recess is formed in the separate housing and/or the control box to accommodate the control line.
7. A control box according to claim 1 or claim 2 wherein the control means comprises a switch arranged in the control box.
8. A control box according to claim 7, wherein' the actuating device arranged in the separate housing is mechanically coupled to the control means.
9. A control box according to claim 8, wherein the separate housing is mechanically coupled to the control means by a flexible cable.
10. A control box for a positioning drive substantially as hereinbefore described and with reference to Figure 1, Figure 2 or Figure 3 of the accompanying drawings.