GB2253240A

GB2253240A - An assembly for connecting an operating member of a latch to a handle

Info

Publication number: GB2253240A
Application number: GB9204083A
Authority: GB
Inventors: Stephen Hopper
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-02-26
Filing date: 1992-02-26
Publication date: 1992-09-02
Anticipated expiration: 2012-02-26
Also published as: GB2253240B; GB9204083D0; GB9104024D0

Abstract

The assembly includes two elongate members 13 which are interconnected by a rotary element 18 having lefthand and righthand threads. The members 13 can be positioned so as to interconnect a latch operating member 10 and two door handles 25 so that operation of the handles operates the latch 11. The members 13 are to be moved apart to disengage the operating member 10 so the operation of the handles will not operate the latch. To move the members 13 apart, the element 18 is turned by a key 22 which passes through a hole 27 formed in one of the handles. <IMAGE>

Description

AN ASSEMBLY FOR CONNECTING AN OPERATING MEMBER OF A LATCH TO A HANDLE The invention relates to an assembly for connecting an operating member of a latch to a handle.

Doors are often provided with a mortice latch mechanism for holding the door closed. The latch is normally operated by door handles provided one each side of the door.

The latch normally includes an operating member which is usually a barrel having a square inner cross-section. The operating member is arranged to rotate and operate a latching member for engaging a recess in a frame member adjacent the door.

Normally, the operating member is rotated by a square section bar which extends through the barrel and is located in each door handle.

Movement of the door handle therefore -operats the latching member.

In order to lock a door having such a mortice latch, it is common practice either to fasten a bolt to the door or to utilise a combination unit which comprises a mortice body having a latch and a key operated bolt therein. Problems arise here as in the former case it can be unsightly to fasten a bolt to the door and in the latter case the unit can prove expensive and an inconvenience to fit as a large mortice has to be formed in the door.

An object of the present invention is to reduce the foregoing problems.

According to a first aspect of the present invention there is provided an assembly for connecting an operating member of a latch with a handle, the assembly comprising an elongate member and a screw threaded element associated with the elongate member whereby, in use, one end of elongate member operatively engages one of said handle and operating member and the elongate member is movable by rotation of the element to enable the other end of the or each elongate member to be moved into and out of operative engagement with the other of the handle and operating member.

When the element engages both the handle and the operating member, movement of the handle operates the latch. However, when the elongate member is out of operative engagement with say, the operating member, the door handle is effectively disengaged from the latch and the latch cannot be opened to allow, for example, a door on which the handle is mounted to be opened.

According to a second aspect of the invention, there is provided a kit of parts for converting a mortice latch, the kit comprising an elongate member to replace a conventional elongate member engageable with a handle for turning an operating member of the latch, a screw threaded element for moving the replacement elongate member into and out of engagement with the operating member or handle, and a drill guide for insertion into a socket of the handle, the drill guide being formed with a bore for receiving a drill to enable the handle to be formed with a hole to receive a key for turning the screw threaded element.

Preferably the drill guide has a cross-sectional shape corresponding to that of the socket in the handle.

Preferably the element, which may comprise a rod, threadingly engages within the elongate member.

Preferably a stop is mounted on the elongate member. The stop may include a snap-ring such as a circlip. The stop may also include a washer or sleeve mounted adjacent the snap ring. The stop is arranged to prevent the elongate member from moving further than necessary to bring the elongate member out of engagement with the operating member or handle. This is particularly useful because, in use, the element and elongate member are usually out of sight. Therefore, to disengage the elongate member all that is required is to turn the element until the stop comes into abutment with. for example, an appropriate part of the door handle arrangement.

Preferably two elongate members are arranged coaxially and threadingly engage respective ends of the element for operatively connecting to the operating member respective door handles one each side of the door.

In a preferred embodiment, one elongate member is engageable with the element by a lefthand thread and the other elongate member is engaged with the element by a righthand thread. This arrangement is particularly useful since both elongate members can be mced into or out of engagement with, say, the operating member at the same time.

Preferably the or each elongate member has a chamfered end to enable it to engage easily with the operating member or its associated handle.

An assembly in accordance with the invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a section through an assembly in accordance with the invention; Figure 2 is the assembly of Figure 1 shown in an alternative position; Figure 3 is a section through elongate members of the assembly shown in Figures 1 and 2; Figure 4 is an elevation of a circlip of the assembly shown in Figures 1 and 2; Figure 5 is a view of the assembly shown in Figures 1 and 2 complete with door handles; Figure 6 is a perspective view of an assembly in accordance with the invention; Figure 7 is a perspective view showing a drill guide to assist in drilling a bore through the door handle;; Figure 8 is an elevation of an assembly in accordance with the invention utilising a wire snap ring in place of a circlip, and Figure 9 is a cross-section of the assembly of Figure 8 on line IX-IX in Figure 8.

In Figures 1 and 2 a barrel 10 is rotatable within a mortice latch 11. The barrel 10 has a bore of square cross-section and rotation of the barrel 10 causes movement of a latching member 12 (see Figure 6) which is slidable within the latch mechanism 11.

Two engagement bars 13 (shown unsectioned for clarity in Figures 1 and 2) lie coaxial with the barrel 10. Each engagement bar 13 (constituting an aforesaid elongate member) is of square crosssection dimensioned to be a close fit within the barrel 10 and has a threaded bore 14. One end of each elongate bar 13 has chamfered corners 9 to facilitate engagement within the barrel 10.

Adjacent said one end of each elongate bar 13 there is an annular recess 15 within which a circlip 16 is fitted. A plurality of washers 17 lie in abutment with the circlip 16. The diameter of the circlip 16 is greater than the width of the square bore of the barrel 10. The recess 15 in each bar 13 may simply cut through corners of the bar as in Figure 9 to form four separate recesses 15a instead of a single annular recess.

The engagement bars 13 are connected to each other by a screw threaded element 18. The threaded element 18 comprises a central unthreaded shank 19 with two end portions 20, 21 having lefthand and righthand threads respectively. The end portions 20, 21 threadingly engage with correspondin threaded bores 14 of the engagement bars 13. A hexagonal recess 23 is provided at one end or each end of the element 18. A key 22 has a hexagonal end to locate within the recess 23 for turning the element 18 as shown in Figure 5.

The engagement bars 13 are symmetrically disposed at each side of the barrel 10.

In Figure Sr the latch is mounted within a door 24. Door handles 25 have a central socket 26 closed at one end. Each socket 26 is square in cross-section and is located over the end of one of the engagement bars 13. A bore 27 extends between the outer surface of each handle 25 and the closed end of the socket 26 and is aligned with the element 18 and engagement bars 13.

Each handle 25 is rotatable within a bearing 28 on a casing 29. The casing 29 may be fixed to the door by suitable fasteners, for example,.screws.

In Figure 6, the two engagement bars 13 are shown one on each side of the latch 11 with the element 18 connecting the two bars. A cuboid spacing 31 defining the square bore of the barrel 10 is shown in broken outline. A front plate 32 is attacks at one end of the latch 11 and the latching number 12 is movable through an aperture in the front plate 32.

In order to form the bore 27 a drill guide 36 may be provided as shown in Figure 7. In Figure 7, the drill guide 36 comprises a square cross- section bar having a central bore 33 for receiving a drill bit 35. In use, the bar 32 is inserted in the socket 25 of each handle 25 in turn on the desired handle and the drill bit is passed through the bore 33 to drill a bore 27 in the handle 25.

The drill guide 36 is a close fit within socket 26 and accurately positions the hole 27 in alignment with element 18. Operation of the assembly will now be described.

In use, the key 26 is inserted through the bore 27 in one of the handles 25 and the end is engaged within the hexagonal recess 23 at one end of the element 18. Turning the key thereby turns the element 18.

Since one engagement bar 13 is engaged on the element 18 by a lefthand thread and the other bar 13 is engaged on the element 18 by a righthand thread, axial rotation cf the element 18 will cause the engagement bars 13 te move apart or together.

When the engagement bars 13 are in abutment with each other as shown in Figure 1, the ends of both engagement bars 13 engage within the square bore of the barrel 10 and within the sockets 26 of handles 25. Rotation of either engagement bar 13 by means of the handle 25 thereby rotates the barrel 10 which causes the latch 11 to operate ncrmally.

In order to prevent the handle operating the latch 11, the key 22 is inserted through bore 27 and is located in one of the hexagonal recesses of element 18. Rotation of the element 18 then causes the elongate bars 13 to move apart as shown in Figures 2 and 5 further into the sockets 26.

The washers 17 and circlip 16 are arranged to provide a stop for abutment with the bearing 28, thereby preventing the engagement bars 13 from moving further than necessary to disengage the barrel 10. As the engagement bars 13 cannot be seen by the user, this arrangement prevents unnecessary winding of the element 18. The number of washers 17 can be selected to control the decired outward travel of the bars 13 and, if desired, can be replaced by a sleeve of an axial length corresponding to the desired number of washers on each bar 13.

In the Figure 5 position the engagement bars 13 are disengaged from the barrel 10. Therefore operation of the handles will not move the latching member 12 and so the latch effectively serves as a lock.

Instead of using a circlip as in Figure 4, a wire snap ring 0 can be used as shown in Figures 8 and 9. The snap ring will normally be used in conjunction with one or more washers 17 or a sleeve and the assembly operates in a manner similar to that described with reference te Figures 1 to 7.

While an element 18 has been described herein having one end with a lefthand thread and the other end with a righthand thread, it should be appreciated that an element having a single-handed thread can alternatively be used with a single engagement bar 13. Such an arrangement could be used where a single handle 25 only is used on a door and cperation of the element could be arranged to disengage the single handle from the barrel 10. In such a case, a suitable retention device should be used to prevent axial m-- -ement of the element relative to its handle.

If desired, one handle 25 only may be formed with a bore 27 so that the element 18 can be turned from one end only. In that case, a hexagonal recess may be provided at only one end of the threaded element 18. In that way the user can choose from which rcom the element 18 can be turned.

Whilst a drill guide 36 has been described herein having a square cross-secticn, a guide having an annular cros---sect.on could also be used. In the latter case, the outer diameter of the annular guide would be selected to enable the guide te be a close sliding fit in the socket 26. The internal diameter of the annular guide would be selected to receive the drill 35.

Whilst specific reference has been made to a door latch, the assembly could be used on a window latch.

The assembly along with the drill guide 36 can be sold as a kit to enable a user to replace the conventional square bar of a mortice lock with the engagements bars 13 and element 18.

Claims

1. An assembly for connecting an operating member of a latch with a handle, the assembly comprising an elongate member and a screw threaded element associated with the elongate member whereby, in use, one end of elongate member operatively engages one f said handle and operat ng member and the elongate member is movable by rotation of the element to enable the other end of the or each elongate member to be moved into and out of operative engagement with the other of the handle and operating member.

2. An assembly according to Claim 1, in which the element threadingly engages within the elongate members.

3. An assembly according to Claim 1 or 2, in which the element is a rod.

4. An assembly according to Claim 1, 2 or 3, in which the element is rotatable by inserting a key through an aperture in the handle so as to engage the element drivably.

5. An assembly according to Claim 4, in which the key is locatable in a recess in the element.

6. An assembly according to any preceding claim, in which a stop is provided on the elongate member.

7. An assembly according to Claim 6, in which the stop includes a snap ring.

8. An assembly according to Claim 6 or 7. in which the stop includes a washer or sleeve.

9. An assembly according to any preceding claim, in which two elongate members are arranges coaxially and threadingly engage respective of the element f operc.ively connecting respective handles one each side of the latch so the operating member.

10. An assembly according to Claim 9, in which one elongate member is engageable with its associated element by a lefthand thread and the other elongate member is engaged with the other element by a righthand thread.

11. An assembly according to any preceding claim, in which the or each elongate member has a chamfered end to enable it to engage easily with the said one of the operating member and associated handle.

12. A kit of parts for converting a mortice latch, the kit comprising an elongate member to replace a conventional elongate member engageable with a handle for turning an operating member of the latch, a screw threaded element for moving the replacement elongate member into and out of engagement with one of the operating member and handle, and a drill guide for insertion int a socket of the handle, the drill guide being formed with a bore for receiving a drill te enable the handle to be formed with a hole tc receive a kej fcr trying the screw threaded element.

13. A kit according to Claim 12, in which the drill guide has a cross-sectional shape -orresponding to that of the socket in the handle.

14. A kit according to Claim 12 or 13, in which the element is threadingly engageable with the elongate member.

15. A kit according to Claim 12, 13 or 14, in which a key is provided and the element has a recess therein for engagement with the key whereby the key can drivably engage the element.

16. A kit according to any of Claims 12 to 15, in which a stop is provided on the elongate member.

17. A kit according to Claim 16, in which the stop includes a snap ring.

18. A kit according to Claim 16 or 17, in which the stop includes a washer or sleeve.

19. A kit according to any of Claims 12 to 18, in which two elongate members are provided which, in use, are arranged coaxially and threadingly engage respective ed cf the element for operative connecting respective handles one each side of the latch to the operating member.

20. A kit according to Claim 19, in which one elongate member is engageable with the element by a lefthand thread and the other elongate member is engageable with the element by a righthand thread.

21. A kit according to any of Claims 12 to 20, in which the or each elongate element has a chamfered end to enable it to engage easily with said one of the operating member and associated handle.

22. An assembly for connecting an operating member of a latch to a handle constructed and arranged substantially as described with reference to Figures 1 to 7 or Figures 8 and 9 of the accompanying drawings.

23. A kit of parts for converting a mortice latch, substantially as described herein with reference to Figures 1 to 7 or Figures 8 and 9 of the accompanying drawings.