GB2136492A

GB2136492A - Lockable twist fastener

Info

Publication number: GB2136492A
Application number: GB08406405A
Authority: GB
Inventors: Franz-Josef Knoop
Original assignee: Nixdorf Computer AG; Nixdorf Computer Corp
Current assignee: Nixdorf Computer AG; Nixdorf Computer Corp
Priority date: 1983-03-16
Filing date: 1984-03-12
Publication date: 1984-09-19
Also published as: DE8307692U1; FR2542831B3; FR2542831A3; GB8406405D0; NL8400623A

Abstract

A door comprises an outer wall 20 and an inner wall 21 having seated therebetween an assembly block 22 to which a cylinder lock 23 is secured. The door is arranged to close an aperture in a apparatus wall 36. The cylinder lock 23 has a lock cylinder 28 extending beyond the outer wall 20 so that a key 30 can be introduced into the lock cylinder 28. Location of the key rotates a catch pivot pin 33 arranged to co-operate with a retaining cam 35 in the apparatus wall 36 so that a toggle 34 on the pin 33 can be locked to the retaining cam by a quarter revolution of the catch pivot pin 33. In this way a secure quick-acting catch is achieved. A toggle element is described for the lock cylinder which allows the conversion of 180 DEG rotating movement of the cylinder lock to be converted into a quarter turn of currently used quick-acting catches. <IMAGE>

Description

SPECIFICATION Device for the disengageable connection of two parts after the style of a twist catch The invention relates to a device for the disengageable connection of two parts after the style of a twist catch, having a catch pivot pin arranged rotatably on the first part, which pin, when the parts lie against one another, is guided through an opening of the second part and is lockable with a retaining cam arranged on the second part, by a rotating movement.

Devices of this kind are also called quickacting catches and be used wherever parts are to be disengageably connected with one another in a simple and uncomplicated manner. This is, for example, the case in the securing of sheet metal coverings in apparatus construction or bodywork building. If an interior space must be opened frequently but complicated catch devices are undesired, use is made of the quick-acting catch.

Fig. 1 shows one possible form of embodiment of such a quick-acting catch pertaining to the prior art. It serves for the connection of two parts 1 and 2 which can consist for example of sheet metal. In the part 1 an opening 3 is provided in which a catch pivot pin 4 is rotatably arranged. The catch pivot pin 4 has at its one end a head 5 with a slot 6 for the insertion of a screw driver and at its other end a toggle 7. The second element of the quick-acting catch, namely a retaining cam 8, is secured with rivets 9 on the part 2 so that it is arranged over an opening 10 of the second part 2. As a result of its formation as shown in Fig. 1 the retaining cam 8 is resilient.When the two parts 1 and 2 lie one on the other, the catch pivot pin 4 with the toggle 7 is guided through the opening 10 and through the middle part of the retaining cam 8 on which the toggle 7 can then be locked for example by a quarter turn of the catch pivot pin 4. As a result of the spring properties of the retaining cam 8 a firm seating of the two parts 1 and 2 on one another results.

The resilient holding together of the two parts 1 and 2 can also be realised in that the catch pivot pin 4 is provided with a spring element.

In the manufacture of apparatus housings quick-acting catches of the known type can be used very advantageously, for example for the disengageable closure of housing interiors by means of hinged flaps or doors. Now it has appeared that this simple type of closure is inadequate when specific spaces must be opened only by authorised persons, as is the case for example with highly complicated data-processing apparatus. For regular servicing work apparatus housing can be made accessible by simple quick-acting catches, but data storage zones or highly sensitive equipment for example may require special treatment or the maintenance of secrecy and therefore be accessible only to specific authorised persons.

Here the requirment now arises not to forgo the principle of the quick-acting catch, with the aim of the most simple and cost-saving manufacture possible, but at the same time to present the possibility of increased security against unauthorised opening of such closures.

It is the problem of the invention to indicate a construction which makes it possible, while maintaining manufacturing specifications which are as simple and constant as possible, to use according to choice a quick-acting catch of simple type or a device for securing against opening by unauthorised persons.

For a device of the initially stated kind this problem is solved in accordance with the invention in that the- catch pivot pin is connected with the lock cylinder of a cylinder lock.

Due to the invention it becomes possible, without forgoing the simple principle of the quick-acting catch, to use according to choice a quick-acting catch operable with a simple tool or manually or a quick-acting catch with cylinder lock. The simple quick-acting catch can be replaced by a quick-acting catch with locking cylinder without the need to alter the essential fitting conditions for the quick-acting catch itself. This has the consequence that the manufacture of apparatus housings for example is not complicated by special security requirements and that with completed equipment it can be decided according to choice whether simple quick-acting catches or quickacting catches with cylinder lock are to be used.

The catch pivot pin is advantageously mounted rotatably in an assembly block holding the cylinder lock and secured to the first part. Then a disengageable coupling connection is provided between catch pivot pin and lock cylinder. Such a construction offers the advantage that standardised cylinder locks can be used which merely need to be fitted to and connected firmly with the assembly block.

The disengageable coupling connection is expediently realised in that a toggle element provided on the lock cylinder is coupled with a twist head provided on the catch pivot pin.

As will be shown hereinafter, such a coupling principle also renders possible the conversion of a 1804 rotating movement of a cylinder lock into a quarter turn of currently used quick-acting catches.

According to a further development of the invention the twist head is provided with a stop pin extending into the assembly block and guided therein in an aperture which limits the rotating movement to a predetermined angular range. Thus the object is achieved that irrespective of the range of rotation of a cylinder lock the range of rotation of the catch pivot pin is always limited to the angular range as intended for the quick-acting catch.

If a retaining cam after the style of a quarter-turn catch and a cylinder lock having a key-turning path of 90 to each side of the key insertion and withdrawl position are provided, then the twist head comprises two mutually diametrically opposite stop elements for the toggle element of the lock cylinder which form a free rotation space of 90 for the toggle element in the circumferential direction of the twist head, starting from the end position in each case of the lock cylinder.

In this way the object is achieved that currently used quarter-turn catches can be used as quick-acting catches together with the cylinder locks mostly used in apparatus construction which permit of turning the key 90 to each side of the neutral position. The free rotation space of 90 for the toggle element results, starting from each end position of the lock cylinder, firstly in each case in an idle rotation over a range of 90 , which is then followed by a further rotation of 90 in which the catch pivot pin is also rotated.

Further features and special advantages of the invention appear from the following description of an example of an embodimer by reference to Figs. 2 to 5, wherein : Figure 2 shows a partially sectional lateral view of the overall arrangement of a quickacting catch with cylinder lock, in the installed condition, Figure 3 shows the longitudinal section III 111 (Fig. 4) of the assembly block as shown in Fig. 1, Figure 4 shows the view IV-IV of the assembly block and Figure 5 shows the section V-V from Fig.

3.

In Fig. 2 there is shown in a partial section the door of an apparatus housing which has an outer wall 20 and an inner wall 21. In the cavity formed between these two walls 20 and 21 there is seated an assembly block 22 to which a cylinder lock 23 is secured, for which purpose by way of example a screw connection can be provided at 24 which connects a support extension 25 of the assembly block 22 with the under side of the cylinder lock 23. It can be seen that the overall length of the assembly block 22 with cylinder lock 23 secured thereto corresponds to the distance between the two walls 20 and 21. This means that in the case of such a fitting the assembly block should expediently be so dimensioned that its length determines the overall length of the arrangement in the manner as described.

The assembly block 22 can be screwed at 26 with the inner wall 21 of the door. Moreover transverse bores 27 are represented which render possible the lateral securing or screwing of the assembly block on a narrow side (not shown in Fig. 2) of the door or to a retaining angle piece or a similar element.

The lock cylinder 28 of the cylinder lock 23 protrudes to the exterior through an opening 29 of the outer wall 20. Thus a key 30 can be introduced into the lock cylinder 28. On its inner side the lock cylinder 28 is provided with a toggle element 31 which engages in a twist head 32 of a catch pivot pin 33 which is mounted rotatably in the assembly block 22.

The catch pivot pin 33 is provided at the outer end of its shank with a toggle 34 which can be locked in a manner known per se with a retaining cam 35, as already described at the outset with reference to Fig. 1. This retaining cam 35 is mounted on a wall 36 of the housing or apparatus on which the door with the walls 20 and 21 is arranged. When the door is moved with the inner wall 21 to the apparatus wall 36, the toggle 34 comes into the region of the retaining cam 35 and can be locked thereto by a quarter revolution of the catch pivot pin 33.

Fig. 3 shows a longitudinal section of the assembly body 22 with the catch pivot pin 33 mounted therein. The twist head 32 at the right end of the catch pivot pin 33 carries a stop pin 37 protruding into the interior of the assembly body 22 and guided in the assembly body 22 in a turning aperture which is so dimensioned that it limits the pre-determined end positions of the catch pivot pin 33 and of the quick-acting catch. Fig. 3 further shows on the twist head 32 a protruding stop element 38, the function of which will be described hereinafter.

In Fig. 4 there is shown the view in the direction IV-IV in Fig. 3. Here the profile of the assembly body 22 may be seen which largely corresponds to that of the cylinder lock 23 (Fig. 2) which is seated on the support extension piece 25 and can be screwed thereto. It can further be seen that the twist head 32 has two stop elements 38 which in the circumferential direction of the twist head 32 form a free turning space for the toggle element 31 (Fig. 2) of the cylinder lock 23.

The two stop elements 38 are diametrically opposite to one another and are so dimensioned that in the example of the embodiment as illustrated the free turning space occupies an angle range of 90 . If the position of the twist head 32 as shown in Fig. 4 corresponds for example to the one end position of the quick-acting catch in which the toggle 34 on the catch pivot pin 33 occupies the vertical position as shown in Figs. 2 and 3, then the horizontal position can be reached by a quarter turn.If for this purpose a turn in the counter-clockwise direction, in the view as shown in Fig. 4, is necessary and the toggle element 31 (Fig. 2) of the cylinder lock assumes its horizontal position, which is as sumed to correspond to one end position of the cylinder lock, then it will firstly carry out an idle rotation of 90 in the counterclockwise direction before it arrives on the two stops 38 and can turn the twist head 32 by a further 90 in the counter-clockwise direction.

Then the twist head 32 comes into a position in which the cylinder lock is situated in its other end position.

Fig. 5 shows the section V-V from Fig. 3 to illustrate the stop pin 37 on the catch pivot pin 33. The stop pin 37 is guided in an aperture 40 within the assembly body 22.

This aperture 40 is dimensioned so that a rotation of the catch pivot pin 33 is possible only over an angle range of 90 , which is prescribed by the function of the quick-acting catch as described.

In the practical case as shown in Fig. 2 it can be seen that a catch pivot pin of the known kind as shown in Fig. 1 can also be used in place of the assembly body 22 and the cylinder lock 23, without modification of the walls 20 and 21. This pivot pin is then situated on the inner wall 21 and is accessible for the purpose of actuation through the opening 29 of the outer wall 20.

Claims

1. Device for the disengageable connection of two parts after the style of a twist catch, having a catch pivot pin arranged rotatably on the first part, which pin, when the parts lie one against the other, is guided through an opening of the second part and is lockable by a rotating movement with a retaining cam arranged on the second part, characterised in that the catch pivot pin is connected with the locking cylinder of a cylinder lock.

2. Device according to Claim 1, characterised in that the catch pivot pin is rotatably mounted in an assembly block retaining the cylinder lock and secured on the first part, and in that a disengageable coupling connection is provided between the catch pivot pin and the locking cylinder.

3. Device according to Claim 2, characterised in that a toggle element provided on the locking cylinder is coupled with a twist head provided on the catch pivot pin.

4. Device according to Claim 3, characterised in that the twist head is provided with a stop pin protruding into the assembly block and guided therein in an aperture limiting the rotating movement to a predetermined angle range.

5. Device according to Claim 4, having a retaining cam after the style of a quarter-turn catch and a cylinder lock with a key rotation distance of 90 to each side of the key insertion and withdrawl position, characterised in that the twist head comprises two mutually dimetrically opposite stop elements for the toggle element of the locking cylinder which form, in the circumferential direction of the twist head, starting from each end position of the locking cylinder, a free turning space of 90 for the toggle element.

6. Device according to Claim 5, characterised in that the rotating movement of the stop pin is limited to an angle of rotation of 90 and in that the aperture is arranged in conformity with the quarter turn of the catch pivot pin.

7. Device according to any one of Claims 2 to 6, characterised in that the assembly block has a cross-section approximately conforming with that of the cylinder lock and is provided with a support extension for the under side of the cylinder lock.

8. Device according to Claim 7, characterised in that the support extension is screwed to the cylinder lock.

9. Device according to any one of Claims 2 to 8, characterised in that the assembly block comprises at least one transverse bore for a securing element for the purpose of fitting on the first part.

1 0. Device according to any one of Claims 2 to 9, characterised in that the assembly block comprises at least one countersunk bore on the end face facing the first part, for the purpose of fitting on the first part.

11. Device according to any one of Claims 2 to 10, for fitting in the door of an apparatus housing, between the outer and inner walls of which a cavity is formed, characterised in that the length of the assembly body with cylinder lock retained thereon is dimensioned according to the width of the cavity.

1 2. Device for the disengageable connection of two parts after the style of a twist catch, substantially as herein described with reference to Figs. 2 to 5.