WO2011042692A2

WO2011042692A2 - Permission mechanism

Info

Publication number: WO2011042692A2
Application number: PCT/GB2010/001863
Authority: WO
Inventors: Keith Brian Allingham; William Andrew Boustead; João Antonio DE OLIVEIRA SILVESTRE
Original assignee: Castell Safety International Limited
Priority date: 2009-10-05
Filing date: 2010-10-05
Publication date: 2011-04-14
Also published as: GB2474078A; GB0917409D0

Abstract

A permission mechanism comprising a first part (2); a second part (3) corresponding with said first part (2) and engagement means (7) for engaging the first part (2) with the second part (3). The engagement means (7) are movable between a disengaged unlocked position and an engaged locked position for locking the first part (2) with the second part (3). The engagement means (7) are configured to disengage the first part (2) from the second part (3) due to a magnetic force produced between the engagement means (7) and a third part (10).

Description

PERMISSION MECHANISM

The present invention relates to a permission mechanism, in particular, but not exclusively, an access bolt permission mechanism. Such an access bolt permission mechanism may, for example, be used to release a safety interlock key.

Conventional access bolt permission mechanisms generally make use of a bolt, which must be inserted into the permission mechanism in order to allow a safety interlock key to be released. When the safety interlock key is removed, the bolt is trapped in the permission mechanism allowing the bolt to control the opening of doors for example.

The present invention seeks to overcome or at least ameliorate some of the problems associated with the prior art. According to a first aspect of the present invention, there is provided a permission mechanism comprising: a first part; a second part corresponding with said first part; engagement means for engaging the first part with the second part; the engagement means being movable between a disengaged unlocked position and an engaged locked position for locking the first part with the second part; the engagement means being configured to disengage the first part from the second part due to a magnetic force produced between the engagement means and a third part.

According to a second aspect of the present invention, there is provided a part configured to be received by and produce a magnetic force to disengage the engagement means in a permission mechanism according to the first aspect of the invention.

According to a third aspect of the present invention, there is provided an access interlock assembly comprising a permission mechanism according to the first aspect of the assembly, the permission mechanism being connected to a safety interlock key mechanism.

According to a fourth aspect of the present invention, there is provided a kit comprising: an access interlock assembly according to the third aspect of the invention; and an access control means according to the second aspect of the invention.

Preferred features are defined in the dependent claims. The present invention will now be described by way of example, with reference to the drawings in which: Fig. 1 is cross sectional view of a permission mechanism according to an embodiment of the present invention on a plane perpendicular to the central axis of the mechanism;

Fig. 2 is a cross-section along the central axis of the mechanism of Fig. 1; Fig. 3 is a cross-section along the central axis of the mechanism of Fig. 1 showing a magnetic bolt being inserted into the central bore of the mechanism;

Fig. 4 is a cross-section of the mechanism according to Fig. 1 showing the magnetic bolt fully inserted into the mechanism;

Fig. 5 is a perspective view of a mechanism according to Fig. 1 ;

Fig. 6 is a cross sectional view of a further embodiment of the present invention on a plane perpendicular to the central axis of the mechanism; and

Fig. 7 is a cross-section of the mechanism of Fig. 6 along a central axis of the mechanism.

Fig. 8a is a cross section through an access interlock assembly including a permission mechanism according to a further embodiment of the present invention, with an interlock key present.

Fig. 8b is a cross section through the plane B-B of Fig. 8a. Fig. 9a is a cross section through an access interlock assembly of Fig. 8a, with a magnetic bolt in place and the interlock key removed.

Fig. 9b is a cross-section through the plane B-B of Fig. 9a.

Fig. 10 is a cross section through a further access interlock assembly including a permission mechanism. Fig. 1 shows a permission mechanism generally at 1 according to a preferred embodiment of the present invention. The mechanism 1 comprises a first part in the form of an inner housing 2 for engagement with a corresponding second part in the form of an outer housing 3. As shown in Figure 2, the inner housing 2 is formed as a generally axially extending ring 4. Integrally formed with the axially extending ring 4, and at one end thereof, the inner housing 2 comprises a radially extending mounting flange 11 for mounting the permission mechanism in an outer housing such as the outer housing 220 of the embodiment shown in Figure 8a. The ring part 4 of the inner housing 2 comprises six equiangularly spaced cavities or pockets 6. The pockets 6 are located around the outer circumference of the ring part 4 of the inner housing 2. Each pocket 6 is configured to receive engagement means, which in the embodiment shown, is in the form of a spherical ball or ball bearing 7. The pocket 6 is configured to permit the ball bearing to move in a radial direction, such that the ball bearing 7 may project at least partially outwardly in a radial direction with respect to the axis of the ring 4 beyond the outer circumference of the ring 4 of the inner housing 2. The pockets 6 are shown formed as blind holes.

The outer housing 3 is formed as a generally axially extending ring 5, closed at one end. The inner housing 2 and the outer housing 3 are formed such that the ring part 4 of the inner housing 2 may be inserted into the ring part 5 of outer housing 3. In this way, the inner housing 2 and the outer housing 3 fit concentrically with each other. When the ring part 4 of the inner housing 2 is fully inserted into the outer housing 3, the engagement means, in the form of the ball bearings 7, are free to move in a radial direction between a position in which they engage with a circumferential rectangular groove or channel 8 that extends around the inner surface of the ring part 5 of the outer housing 3, and a disengaged position in which the ball bearings 7 are located in the bottom of their respective pocket 6. In the disengaged position, the first part, i.e inner housing 2 is disengaged from the second part, i.e. outer housing 3 and the two parts may move axially relative to one another. In the engaged position, the first part 2 is locked with the second part 3 and therefore the two parts may not move relative to one another. When the first and second parts 2, 3 are locked together, the second part 3 is not permitted to move. The second part may be connected to a safety interlock key mechanism 222 for receiving a safety interlock key 221 , such as that shown in Figure 8a. The displacement of the second part 3 by a predetermined distance with respect to the first part 2 then permits the safety interlock key 221 to be turned and removed. The inner housing 2 additionally comprises holding means in the form of a set of equiangularly spaced ball bearings 9 located around the circumference of the ring of the inner housing 2. This further set of ball bearings 9 are sized to be larger than the ball bearings 7 which form the engagement means. The second set of ball bearings 9 are located in through holes 16 in the ring part 4 of the inner housing 2 such that they are movable and may project from either the internal or outer circumference of the ring part 4. In order to prevent the second set of ball bearings 9 falling out of the ring part 4, the through holes 16 have a smaller diameter at the inner circumference of the ring part 4 of the inner housing 2 than at the outer circumference of the ring part 4 with respect to the central axis of the ring part 3. In the embodiment shown, the second set of ball bearings 9 comprise four ball bearings 9 equiangularly spaced at 90 degrees around the circumference of the inner housing 2.

When the inner housing 2 is fully inserted into the outer housing 3, the engagement means, in the form of the ball bearings 7, are aligned with the circumferential groove 8 of the outer housing 3. The engagement means, in the form of the ball bearings 7 are then free to engage in the circumferential groove 8. In this way the second part, i.e. the outer housing 3 serves as a receiving means to receive the engagement means 7. As can be seen in Fig. 1 , due to the force of gravity, the lowermost ball bearings 7, with respect to a vertical plane orthogonal to a central axis of the ring part 4, engage in the circumferential groove 8 of the outer housing 3. The ball bearings 7 located at the top, i.e. the highest most point of the inner housing 2 in the vertical plane, do not engage with the circumferential groove 8 of the outer housing 3. The ball bearings 7 located between the uppermost position and the lowermost position of the inner ring 2 partially engage with the circumferential groove 8. With the lock arranged with the ball bearings 7 and the pockets 6 in a vertical plane orthogonal to the central axis of the ring part 4, depending on the rotational orientation of the permission mechanism, the force of gravity will ensure that a number of the ball bearings 7 will lie in the groove 8 in the outer housing 3.

Because the ball bearings 7 engage with the circumferential groove 8 in the outer housing 3, the inner housing 2 is therefore engaged or locked together with the outer housing 3. In this state, the second part 3 may not be moved relative to the first part 2 and a connected interlock key 221 as shown in the embodiment of Figure 8a may not be operated. As shown in Fig. 3, in order to disengage the inner housing 2 from the outer housing 3, a third part, which in the embodiment shown is in the form of a cylindrical magnetic bolt 10, is inserted into the central bore formed by the ring 4 of the inner housing 2. The third part may be formed as an access bolt as it may be used as a fastener to control access through a door for example. Other suitable access bolts or fasteners are also envisaged. The central bore forms a receiving means for receiving the bolt 10. The open end of the inner bore of the ring 4 tapers in order to facilitate insertion of the bolt 10 into the ring part 4. The bolt 10 comprises a high-powered neodymium magnet 12 in its tip. The engagement means in the form of the ball bearings 7 are comprised of martensitic stainless steel. Other suitable magnetic materials are also envisaged. As the magnetic bolt 10 is inserted into the ring 4 of the inner housing 2, due to the attractive magnetic force produced between the ball bearings 7 and the bolt 10, the first set of ball bearings 7, i.e. the engagement means, are attracted radially inwardly towards the bolt 10 and the central axis of the inner ring 4 of the inner housing 2. In this way, the ball bearings 7 disengage from the circumferential groove 8 in the outer housing 3 thereby disengaging the inner housing 2 from the outer housing 3.

The magnetic bolt 10 is provided towards an end thereof with a circumferential indent or groove 13 on its outer circumference. This circumferential groove 13 is formed to engage with the second set of ball bearings 9. As the bolt 10 is inserted, the second set of ball bearings 9 are also drawn towards the bolt 10 by a magnetic force produced between the bolt 10 and the ball bearings 9. The bolt 10 is shaped, for example as a shallow cone, to enable the tip 14 of the access bolt to be pushed readily past the second set of ball bearings 9 so that the second set of ball bearings 9, i.e. holding means, may then locate in the circumferential groove 13 of the access bolt 10.

The outer housing 3 has a circumferential groove 15 on its inner circumference, formed to partially receive the second set of ball bearings 9. This groove 15 allows the second set of ball bearings 9 to be displaced partially radially into the outer housing to enable the tip of the bolt 10 to be inserted past the second set of ball bearings 9.

The inner housing 2 is fixed in position and is mounted in an access interlock assembly 219 such as in the embodiment shown in Figures 8a to 9b. When the bolt 10 is inserted into the inner housing 2, the engagement means, in the forms of the ball bearings 7 and the holding means, in the form of the second set of ball bearings 9, are attracted radially inwardly thereby unlocking the inner housing 2 from the outer housing 3. The outer housing 3 is then permitted to move in an axial direction relative to the inner housing 2. The outer housing 3 is biased towards the inner housing 2, using biasing means, for example in the form of a coil spring -223, 323 such as shown in the embodiments of Figures 8a to 9b and 10. As the bolt 10 is inserted further into the inner housing 2, the tip 14 of the bolt 10 contacts the closed end of the outer housing 3 and forces the outer housing 3 to move in an axial direction relative to the inner housing 2. The degree of movement depends on the scale of application, but may typically be in the order of 3mm for example. The degree of movement of the outer housing 3 is limited, for example to a predetermined displacement D by the use of a stop 224 such as shown in the embodiment of Figures 8a to 9b, which controls the degree of axial movement or displacement of the outer housing 203. When the outer housing 3 moves over the inner housing 2 to a displaced state, an inwardly protruding circumferential surface of the outer housing locates around the second set of ball bearings 9 to hold the second set of ball bearings 9 in position and lock the bolt 10 in inner housing 2 and therefore also in the permission mechanism 1. A further inwardly protruding circumferential surface 18 on the outer housing 3 locates around the first set of ball bearings.

The outer housing has an extended part 25 with a straight groove 26 and circular recess 27 for connecting with a safety interlock key mechanism 222 such as the safety interlock key mechanism of the embodiment of Figures 8a to 9b.

A further preferred embodiment of the present invention is shown generally as 101 in Figs. 6 and 7. This embodiment is formed similarly to the embodiment shown in Figures 1 to 5 with an inner housing 102 and an outer housing 103. In contrast with the pockets used in the embodiment of Figures 1 to 5 for the engagement means, the first part or inner housing 102 is provided with a circumferentially extending groove 106 which extends around the outer circumference of the ring 104 of the inner housing 102. The groove 106 forms a run for the ball bearings 107. In the embodiment shown, four ball bearings 107 are provided in the circumferential groove 106. The ball bearings 107 are free to move around the circumferential groove 106. When the lock 101 is orientated such that the axis of the inner housing 102 is in a generally horizontal direction, the ball bearings 107 move around the circumferential groove 106 under the force of gravity to the lowermost point of the circumferential groove 106. In this way, all four ball bearings 107 may substantially engage with a corresponding part of the circumferential groove 108 on the inner circumference of the outer housing 103. This embodiment seeks to ensure a more secure engagement of the first part 102 with the second part 103. The ball bearings 107 are disengaged in the same manner as described in the first embodiment by the insertion of a magnetic bolt which attracts the ball bearings 107 radially inwards. A second set- of ball bearings 109 is similarly provided to act as holding means as in the first embodiment. Figures 8a to 9a show an access interlock assembly which includes a permission mechanism 201 of the type described in relation to Figures 6 and 7 above, i.e. where engagement means 207 in the form of ball bearings are located in a circumferential groove 206 in an inner housing 202. The inner housing fits concentrically with an outer housing 203. A further set of ball bearings 209 are used to lock a bolt 210 comprising a magnet 212 in the permission mechanism 201. The locking and unlocking of the permission mechanism 201 functions as described in relation to Figures 6 and 7. The permission mechanism 101 as described in relation to Figures 1 to 5 may equally be used.

The permission mechanism 201 is mounted in an access interlock assembly 219 with a housing 220. The permission mechanism 201 is connected to a safety interlock key mechanism 222 for receiving a safety interlock key 221. Similarly to the embodiment of Figures 1 to 5 and 8a to 9b, the outer housing 3 comprises an extended part 225 which has a straight groove 226 which runs into a circular recess 227. A tang 228 of the safety interlock key mechanism 222 is located in fixed orientation by the straight groove 226 when the permission mechanism 201 is in the locked state. When the outer housing 3 is fully displaced by a distance D, the tang 228 is then located in the circular recess 227 and the tang 228 may then be rotated, thereby allowing the safety interlock key 221 to turn the safety interlock key mechanism 222. Once the safety interlock key 221 has been turned, it may be removed. The position of the tang 228 after the safety interlock key has been removed holds the outer housing 203 in its displaced state. Once the safety interlock key 221 has been removed, the bolt 210 is therefore locked or trapped in the permission mechanism. In the embodiment of Figures 8a to 9b, the central axis of the permission mechanism 201 is perpendicular to the axis of operation of the safety interlock key 221.

In an alternative embodiment such as that shown in Figure 10, the central axis of the permission mechanism 301 is parallel to the axis of operation of the safety interlock key mechanism 322. The bolt 310 operates the permission mechanism 301 as described in relation to the embodiment of Figures 8a to 9b. As shown, the bolt 310 has been received in the permission mechanism 301. In contrast to the embodiment of Figures 8a to 9b, in the embodiment of Figure 10, the central axis of the permission mechanism 301 is parallel to the axis of operation of the safety interlock key mechanism 322 and the safety interlock key (not shown). Further, instead of a tang and groove, in order to lock the displacement of the outer housing 303, by the bolt 310, a notch 334 on the safety interlock key mechanism 322 is rotated when operated and engages with a spigot 333 on the outer housing 303. Such a spigot 133 may also be seen in the embodiment of Figure 6.

The bolt 10, 110, 210, 310 for the permission mechanism may be attached to a sliding door or hinged door. The attachment may be done using a bracket 229, 329 such as that shown in Figures 8a to 9b or 10. To take account of tolerances in alignment between the bolt 10, 110, 210, 310 and the permission mechanism 1 , 101, 201, 301 a flexible joint, for example a Belleville washer 230, 330 may be used in the connection of the bolt 210, 310 in the bracket 229, 329. The embodiment shown in Figures 8a to 9b is suitable for a sliding door (not shown), where the bolt 210 is mounted with its central longitudinal axis in a substantially horizontal alignment on a door leaf. The corresponding access interlock assembly 219 and permission mechanism 201 is mounted on a door frame or corresponding sliding, such that the longitudinal axis of the inner housing 202 is also mounted in a horizontal alignment such that the access bolt 210 may be received in the inner housing 202 when the sliding door is shut. In this way, when the bolt 210 is received in the inner housing 202, the safety interlock key mechanism 222 may be operated and the safety interlock key 221 removed. In this state, the door is locked shut and access is controlled.

The embodiment of Figure 10 is suitable for a hinged door (not shown), where the bolt 310 is mounted with its central longitudinal axis in a substantially horizontal alignment on a door leaf. The corresponding access interlock assembly 319 and permission mechanism 301 is mounted on a door frame, such that the longitudinal axis of the inner housing 302 is also mounted in a horizontal alignment such that the access bolt 310 may be received in the inner housing 302 when the door is shut. In this way, when the bolt 310 is received in the inner housing 302, the safety interlock key mechanism 322 may be operated and the safety interlock key (not shown) removed. In this state, the door is locked shut and access is controlled. The mounting flange 11 , 111 , 211 of the inner housing 2, 102, 202 may be mounted in the access interlock assembly 219 using screw fasteners 231 inserted in holes 32, 132, 232 of the flange 11 , 111 , 211. Although the first part has been described as being receivable in the second part, embodiments are envisaged in which the permission mechanism may be configured such that the second part is received in the first part or received in any other way such that the engagement means may lock the first part with the second part Embodiments of the permission mechanism are also envisaged in which the engagement means are provided with biasing means to bias the engagement means 7, 107, 207 into the circumferential groove 8, 108, 208 of the outer housing. In this way, the ball bearings 7, 107, 207 engage with the circumferential groove 8, 108, 208 irrespective of the orientation of the permission mechanism 1 , 101 , 201. With such an arrangement, the biasing means used to bias the ball bearings 7 are configured such that the biasing means may be overcome by a magnetic force produced by the magnetic bolt 10, 110, 210.

Embodiments are also envisaged, wherein the engagement means comprise a magnet and the access bolt comprises a suitable material to create a magnetic force between the engagement means and the access bolt.

Claims

CLAIMS:

A permission mechanism comprising:

a first part;

a second part corresponding with said first part;

engagement means for engaging the first part with the second part; the engagement means being movable between a disengaged unlocked position and an engaged locked position for locking the first part with the second part;

the engagement means being configured to disengage the first part from the second part due to a magnetic force produced between the engagement means and a third part.

A permission mechanism according to claim 1 , wherein when the engagement means are in the unlocked position, the second part is movable relative to the first part.

A permission mechanism according to claim 2, wherein the permission mechanism is connected to a safety interlock mechanism, and wherein a predetermined movement of the second part relative to the first part permits operation of the safety interlock.

A permission mechanism according to claim 3, wherein movement of the second part is relative to the first part is permitted only when the engagement means are in the disengaged unlocked position.

A permission mechanism according to any one of the preceding claims, wherein the engagement means undergo substantially radial motion with respect to a central axis of the first part between the disengaged position and the engaged position.

A permission mechanism according to any one of the preceding claims, wherein the engagement means are configured to engage the first part with the second part under the force of gravity.

7. A permission mechanism according to any one of the preceding claims, wherein the engagement means are free to run around a circumference of the first part. 8. A permission mechanism according to any one of the preceding claims, wherein the engagement means comprise one or more ball bearings.

9. A permission mechanism according to claim 8 wherein each ball bearing is located in a respective pocket, each pocket being spaced around a circumference of the first part.

10. A permission mechanism according to claim 8, wherein the or each ball bearing is freely located in a run formed as a radial groove around a circumference of the first part.

11. A permission mechanism according to claim 10, wherein the circumference is an outer circumference of the first part.

12. A permission mechanism according to any one of the preceding claims, wherein the first part is configured to be received in the second part.

13. A permission mechanism according to any one of claims 1 to 11 , wherein the second part is configured to be received in the first part. 14. A permission mechanism according to any one of the preceding clams, wherein the engagement means are configured to engage with a circumferential groove on the second part.

15. A permission mechanism according to any one of the preceding claims, wherein the first part includes receiving means for receiving the third part.

16. A permission mechanism according to any one of claims 1 to 14, wherein the second part includes receiving means for receiving the third part.

17. A permission mechanism according to claim 15 or 16, wherein the receiving means is formed as a bore.

18. A permission mechanism according to any one of the preceding claims, wherein the engagement means radially surround the first part.

19. A permission mechanism according to any one of the preceding claims, wherein the mechanism further comprises holding means configured to releasably hold the third part with the first part.

20. A permission mechanism according to claim 19, wherein the holding means is configured to lock the third part in the permission mechanism when the permission mechanism is in the disengaged unlocked state.

21. A permission mechanism according to claim 19 or 20, wherein the holding means comprises one or more ball bearings.

22. A permission mechanism according to any one of claims 19, 20 or 21 , when dependent on claim 2, wherein when the second part moves relative to the first part, the second part is configured to engage with the holding means and lock the holding means to hold the access control means with the first part.

23. A permission mechanism according to any one of the preceding claims, further comprising biasing means to bias the second part towards the first part.

24. A permission mechanism according to any one of the preceding claims, wherein the first part is formed as an axially extending ring.

25. A permission mechanism according to claim 15 or 16, or claims 17 to 24 when dependent on claim 15 or 16, wherein the second part is configured to be moved when the third part is received by the receiving means.

26. A permission mechanism according to any one of the preceding claims, wherein the first part is configured to fit concentrically with the second part.

27. A permission mechanism according to any one of claims 2 to 26, wherein the first and seconds parts are configured to move relative to one another in an axial direction.

28. A permission mechanism according to- any one of claims 2 to 27, the mechanism further comprising a stop configured to limit movement of the second part relative to the first part.

29. A permission mechanism according to any one of the preceding claims, wherein the engagement means comprise martensitic stainless steel.

30. A permission mechanism according to any one of the preceding claims, wherein in the locked position the first part is locked to the second part, the first part being configured to allow the third part to be inserted therein; the engagement means being configured to unlock the first part from the second part when the third part is inserted in the first part, the engagement means being configured to lock the first part with the second part, when the third part is removed from the first part.

31. A part configured to be received by and produce a magnetic force to disengage the engagement means in a permission mechanism according to any one of the preceding claims.

32. A part according to claim 31 , wherein the part comprises a magnet.

33. A part according to claim 32, wherein the magnet is a neodymium magnet. 34. A part according to any one of claims 31 to 33, wherein the part is formed as a cylindrical bolt.

35. A part according to claim 34, wherein the bolt comprises a circumferential groove configured to engage with holding means provided on an associated permission mechanism.

36. An access interlock assembly comprising a permission mechanism according to any one of claims 1 to 30, the permission mechanism being connected to a safety interlock key mechanism.

37. An access interlock assembly according to claim 36, wherein the permission mechanism is configured to allow a safety interlock key in the safety interlock key mechanism to be operated and removed when the permission mechanism is in the unlocked disengaged state.

38. A kit comprising:

a permission mechanism according to any one of claims 1 to 30; and a part according to any one of claims 31 to 35.

39. A kit comprising:

an access interlock assembly according to claim 36 or 37; and

a part according to any one of claims 31 to 35.

40. A permission mechanism substantially as described herein, with reference to and as illustrated in the accompanying drawings.

41. A part configured to be received by and produce a magnetic force to disengage the engagement means in a permission mechanism substantially as described herein, with reference to and as illustrated in the accompanying drawings.

42. An access interlock assembly substantially as described herein, with reference to and as illustrated in the accompanying drawings.